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CASE REPORTS

Coronary Bypass Surgery in Kawasaki Disease in a Four-Year-Old Patient: Case Report Suleyman Ozkan, M.D., Bulent Saritas, M.D., Erdal Aslim, M.D., Tankut Hakki Akay, M.D., and Sait Aslamaci, M.D. Department of Cardiovascular Surgery, Baskent University Hospital, Ankara, Turkey ABSTRACT Kawasaki disease is an acute vasculitis syndrome of unknown etiology that mainly affects small and medium-sized arteries, particularly the coronary arteries. This disease is rarely seen in infants and young people in Turkey. In this short report, we present a four-year-old patient who has Kawasaki disease associated with coronary artery aneurysm and underwent coronary bypass grafting. doi: 10.1111/j.1540-8191.2007.00450.x

(J Card Surg 2007;22:511-513) Kawasaki disease was first introduced by Tomisaku Kawasaki in Japan in 1967. Kawasaki disease is a vasculite syndrome (consisting of mucosal inflammation, skin rash, and cervical lymphadenopathy) that affects small- and middle-sized arteries, especially coronary arteries. Although its etiology is not known, recent belief is that the disease is an immune response composed against some agents such as infections, antigens, or toxins. The long-term clinical course of Kawasaki disease is concerned with the coronary artery lesions that develop aneurysmal formation, thrombotic occlusion, progression to ischemic heart disease, and premature atherosclerosis.1 This disease is very rare in Turkey. In this short report we aimed to present our coronary artery bypass grafting experience with internal thoracic artery in a four-year-old patient who has Kawasaki disease associated with coronary artery aneurysm. CASE REPORT The patient was a 4-year-old male. He was admitted to the hospital with fever and palpitation. Three years ago, he was treated for meningitis. He also had a diagnosis of pericarditis and was treated with steroids for two weeks. In the physical examination, blood pressure was 90/60 mm Hg, pulse was 120/seconds, and fever Address for correspondence: Hakki Tankut Akay, M.D., PK 56, 06552, C¸ankaya, Ankara, Turkey. Fax: (+90)-312-223 73 33; e-mail: [email protected]

was 36.4◦ . There were no pathological symptoms in cardiovascular, respiratory system, and occular examinations. Cervical lymphadenopathy and dermatological signs were not present. Oral mucosa was normal. Peripheral arteries were palpable. In coronary angiography, the diameters of left anterior descending artery (LAD) and left main coronary artery (LMCA) were measured as 6.8 mm; circumflex (Cx) artery was 6 mm; and right coronary was 4.9 mm (Figs. 1 and 2). In laboratory tests, complete blood count, urine test, and kidney and liver functions were normal. Sedimentation rate was 65 mm/hr. C-reactive protein (CRP) was 0.3. The blood and throat cultures were negative. Palpitation has led us to diagnose heart failure and medical treatment was initiated (Acetylsalicilic acid –5 mg/kg, diuretic 1 mg/kg, and digoxin). The diagnosis of Kawasaki was made, and his score was 9 according to the scoring system in Kawasaki disease (Table 1). Median sternotomy was the surgical approach. After opening the pericardium, the left main coronary artery could not be clearly visualized because of dense adhesions due to previous pericarditis. There was no effusion in the pericardial cavity. Aneurysm formation in the left anterior descending (LAD) and proximal circumflex (Cx) artery were detected. The left internal thoracic artery (LITA) was the graft of choice for revascularization of the LAD. The LITA and saphenous vein were harvested. The diameters of LITA and saphenous vein were approximately 1.5 mm. Diameters of two coronary arteries were approximately 1.5 mm, and they were sclerotic. The LITA and saphenous vein were anastomosed to LAD and circumflex obtus major arteries, respectively. The operation was terminated without any event. There was no problem in the intensive care unit and the patient was extubated on the first postoperative day. The patient was discharged on the seventh postoperative day in good condition. The patient was asymptomatic in the follow-up period after 15 months. DISCUSSION Five main symptoms are sufficient for making a diagnosis of Kawasaki disease: fever lasting for five days, bilateral nonexcudative conjunctivitis, changes in extremities, polymorphic exantems, changes in oral mucosa, and acute nonpurulane cervical lymphadenopathy. On the other hand, it can be enough for the diagnosis if there are four of these symptoms and accompanying coronary artery aneurysm shown by echocardiography or angiography.2 In our case, Kawasaki disease was suspected after a history of fever lasting approximately 15 days despite medical treatment. According to the scoring system in Kawasaki disease, nine and more points indicate coronary arterial involvement. The disease does not have a definitive specific treatment because of its unknown etiology. Contemporary treatment includes two main aims: treating the acute

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TABLE 1 Scoring System in Kawasaki Disease Score Clinical Features

Figure 1. Angiographic views of right coronary artery aneurysm.

phase and then preventing coronary arterial thrombosis. Coronary artery aneurysm occurs in nearly 20% of the patients under no treatment, whereas the percentage decreases to 4% to 8% in the patients taking γ -globulin.3 Coronary bypass is used for the subacute phase even if application of the technique is difficult. Preventing myocardial infarction in patients having coronary artery aneurysm is the aim. Most affected segments on the left side are left in main coronary artery and proximal LAD, on the right side are proximal segments of RCA, like in our case. Effects on distal segments of coronary arteries are very rare.3 Operation indication must be planned due to age, history of previous myocardial infarction, coronary angiography, and ischemic areas on myocardial perfusion scans and dysfunctions of left ventricle.3 Angiographic manipula-

Gender Age Fever duration (d) Cardiomegaly Arrhythmia Myocardial ischemia signs and symptoms Pericarditis Repetitive fever Repetitive desquamations Anemia (hemoglobin ≤ 10 g/dL) Lecocytosis Sedimentation rate (mm/h) Prolonged acute phase reactants

0

1

Female 1 15–16 Positive Positive

Negative Negative Negative

Positive

Negative

Positive

≤26 1 wk

tions are very difficult because of fibrosis resulting from thickness of arterial wall, multiple affected areas, and aneurysm formation following existing coronary arteritis.3,4 Graft choice is an important factor affecting the survival. Kitamura and colleagues4 reported a multicenter study of 170 patients with a mean age of 10 years; two early deaths and eight late deaths occurred. Ventricle dysfunction, arrhythmia, and late occlusions in venous grafts were the causes of death. It is interesting that not using LIMA is the most important reason for the late occlusion and poor outcomes of coronary bypass surgery.5 In our study, we preferred to use LIMA as a graft to LAD. In the follow-up period, a control coronary angiography has not been done; yet, determination of no difference with electrocardiographic and echocardiographic studies convinced us that the grafts are patent. There is no knowledge about prevalence of this disease in Turkey. This disease is rarely seen in Turkey but commonly seen throughout the world. This is a case report of a single center, and more CABG operations with long-term results may provide more understanding. However, we may conclude that CABG can be done safely for this age group of patients in ischemic situations, even if surgical technique is technically demanding. We also believe that LITA is the most suitable graft for LAD bypass, which has the highest patency rate because of less sensitivity to degenerative differences. REFERENCES

Figure 2. Angiographic views of left main coronary artery aneurysm.

1. Naoe S, Takahashi K, Mashuda H, et al: Kawasaki disease. With particular emphasis on arterial lesions. Acta Pathol Jpn 1991;41:785-797. 2. Hamashima Y, Tasaka K, Fujuwara H, et al: Kawasaki disease’s pathological features and possible pathogenesis. Acta Pathol Jpn 25:108-117. 3. Koren G, Lavi S, Rose V, et al: Kawasaki disease: Review of risk factors for coronary aneurysms. J Pediatr 1986;108:388-392.

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4. Kitamura S, Kameda Y, Seki T, et al: Long-term outcome of myocardial revascularization in patients with Kawasaki coronary artery disease. A multicenter cooperative study. J Thorac Cardiovasc Surg 1994;107:663-674. 5. Nishioka H, Kitamura S, Kameda Y, et al: Difference in acetylcholine-induced nitric oxide release of arterial and venous grafts in patients after coronary bypass operations. J Thorac Cardiovasc Surg 1998;116:454– 459.

Primary Malignant Fibrous Histiocytoma of the Heart with Skeletal Muscles Metastases Davor Milicic, M.D., Ph.D.,∗ Antonio Juretic, M.D., Ph.D.,† Josko Bulum, M.D.,∗ Nera Saric, M.D.,† Vesna Bisof, M.D.,† Ivan Jelic, M.D., Ph.D.,‡, and Drazen Jelasic, M.D.§ ∗

University Clinic of Cardiovascular Diseases, †Clinic of Oncology, ‡Clinic of Cardiac Surgery, and §Department of Pathology, Clinical Hospital Centre Zagreb, Zagreb, Croatia ABSTRACT Malignant fibrous histiocytoma is an extremely rare primary malignant tumor of the heart. It is usually diagnosed when it is locally aggressive or has already metastasized. The prognosis is poor with an average survival time of one year. We report a case of recurrent left atrial malignant fibrous histiocytoma initially misdiagnosed as myxoma. The patient underwent repeated surgical resections followed by chemotherapy. Despite adjuvant chemotherapy, 18 months after initial diagnosis, definitive tumor relapse in left atrium was diagnosed. This is the 48th case of primary cardiac fibrous malignant histiocytoma reported in the literature. doi: 10.1111/j.1540-8191.2007.00451.x

(J Card Surg 2007;22:513-516) Primary cardiac tumors are rare, with an autopsy incidence ranging from 0.001% to 0.03%.1 About threequarters of these tumors are benign and nearly half of them are myxomas. Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma in adults, but it is extremely rare as a primary tumor of the heart.2 MFH is a malignant tumor of fibroblasts and pleomorphic histiocytoid cells with large number of bizarre, multinucleated giant cells. Their stroma might

Address for correspondence: Josko Bulum, M.D., University Clinic of Cardiovascular Diseases, Clinical Hospital Centre Zagreb, Kispaticeva Street 12, 10 000 Zagreb, Croatia. Fax: +385-1-2312-247; e-mail: [email protected]

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sometimes be myxoid, and they might be occasionally misdiagnosed as a myxoma.3 Cardiac tumors present with one or more symptoms of the classic triad: intracardiac obstruction; systemic embolization; and systemic symptoms such as fever, arthralgia, weight loss, and fatigue. The prognosis of patients having even nonmetastatic primary cardiac sarcomas is relatively poor with very few patients surviving for more than one year after diagnosis.4 Reasons for this dismal outcome are the diagnosis of this type of tumors in advanced stage of disease, impossibility to perform adequate radical tumor excision, and the cardiotoxic side effects of radiotherapy and of some cytotoxic drugs.5 Early cardiac transplantation, if possible, might be a promising therapy for patients with nonmetastatic malignant cardiac sarcomas.6 We present a female patient with MFH of the left atrium. CASE REPORT A 58-year-old white woman was admitted to our hospital in September 2003 with a history of congestive heart failure and bilateral pleural effusion three months ago. She underwent total thyroidectomy with paraglandular resection and subsequent radioactive iodide administration in 2000 because of papillar carcinoma of a thyroid gland. On admission, she was eupnoic in rest and afebrile; blood pressure was 140/90 mm Hg; and heart rate was regular at 96 beats/min. Electrocardiogram revealed sinus rhythm with occasional extrasystolas. Pulmonary, cardiac, and abdominal examinations were unremarkable. There were no palpable lymph nodes. Transthoracic (TTE) and transesophageal echocardiography (TEE) revealed a large, partially mobile tumorous mass 4 cm × 2 cm in the left atrium, which was partially obstructing blood flow through the mitral valve. According to its localization and appearance on echocardiography, the tumor was suggestive of myxoma. No other tumor was found in the chest and abdomen. Open heart surgery under cardiopulmonary bypass was done, and the tumor was successfully resected; histopathology diagnosis was myxoma. Control TTE in December 2003 showed tumor recidive that occupied two thirds of the left atrium. Reoperation was performed in February 2004 and maximal tumor reduction was done. Also the pathological specimen in paraphine block from first operation went for revision. Histopathology diagnosis was MFH (Figs. 1 and 2) for both specimens. No further therapy was applied and the patient was discharged. Control TEE done one month after reoperation showed local tumor recidive in the left atrium (Fig. 3), with complete tumor infiltration of left atrial free walls. CT scan showed no tumor propagation into the pulmonary veins or pericardium, and no systemic metastases were found. Because of the extremely locally aggressive nature of the tumor, the patient was scheduled for orthotopic cardiac transplantation. Subsequently, eight cycles of chemotherapy with doxorubicin and ifosfamide with mesna uroprotection were applied. Control TEE in September 2004 showed tumor remission after chemotherapy. Control echocardiography in April 2005

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Figure 1. Microscopic examination, MFH (H&E stain, ×200). Malignant fibrous histiocytoma revealing fascicles of plump spindled cells of varying size arranged in a swirling storiform pattern. Characteristic is the tendency for the spindle cells to be disposed in a cartwheel storiform pattern.

showed local tumor recurrence in the left atrium measuring 1.2 cm × 1.2 cm. The next check-up in June 2005 indicated a definite tumor relapse because the tumor size increased from 1.2 cm × 1.2 cm to 2.5 cm × 3.9 cm. Moreover, the patient noticed the growing subcutaneous nodule on the plantar surface of her right foot, which was resected in June 2005. The histopathology examination revealed MFH measuring 5 cm × 6 cm. Because of local tumor relapse and distal metastasis, the patient has been removed from the transplantation list. Four cycles of second-line chemotherapy (cyclophosphamide, vincristine, and dacarbazine) were applied from July to September 2005. During the hospitalization for the fourth chemotherapy cycle, CT scan revealed a metastasis measuring 10 cm in diameter located predominantly in the vastus lateralis muscle.

Gemcitabine and docetaxel were chosen for further chemotherapy, and patient received a first cycle in October 2005. Two and a half weeks after she was hospitalized because of acute massive pulmonary embolism, TTE showed tumor recidive, which occupied more than one half of the left atrium (Fig. 4). Her condition improved after conservative therapy, but this improvement was not sufficient for the continuation of chemotherapy. Unfortunately, the only further therapeutic option left is a very risky, life-saving surgical resection in the case of mitral flow obstruction. DISCUSSION Soft-tissue sarcomas are rare tumors accounting for approximately 1% of all cancers worldwide each

Figure 2. Immunohistochemical examination, MFH (vimentin stain, ×200).

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Figure 3. TEE demonstrates early postoperative MFH recidive in the top of the left atrium. LA = left atrium; Ao = aorta; MFH = malignant fibrous histiocytoma.

year. There exists a variety of histological subtypes of sarcomas; the most common is MFH. The choice of treatment generally depends on the location, size, and histological grade of the primary soft tissue sarcoma and the patient’s performance status. Surgical resection with pathologically proven clear margins is the treatment of choice for localized sarcomas. Postoperative radiation therapy plays a major role as an adjunct to surgery in improving local tumor control compared with surgery alone. Chemotherapy is also a treatment modality for the soft tissue sarcomas. Primary cardiac tumors including sarcomas are exceedingly rare. The majority of these are benign, which are often successfully treated by surgical excision. In contrast, malignant cardiac tumors are associated with poor long-term survival despite surgery, radiotherapy and chemotherapy. However, surgical resection is often required for diag-

nosis or to relieve symptoms. MFH is an exceptionally rare primary cardiac tumor. Only 43 cases of surgical therapy for cardiac MFH have been documented since the initial report of Shah et al. in 1978.7 Among reported cases of MFH, 30 patients (63%) were female and 18 patients (37%) were male. The primary location of MFH is in most of the cases in the left atrium, although it has been reported in the pericardium, right ventricle and/or pulmonary valve, right atrium, left ventricle, and at the site of an atrial septal defect. Very few data are available for the most appropriate management of cardiac sarcomas. At present, no uniform consensus exists regarding the best treatment strategies, but therapy requires a multidisciplinary team approach. A radical surgical approach, if possible, represents the only effective therapeutic measure. But, in most of the cases, complete resection is not possible because of

Figure 4. TTE (parasternal short axis) demonstrates MFH recidive that occupied more than a half the left atrium. LA = left atrium; RA = right atrium; RV = right ventricle; AO = aorta; MFH = malignant fibrous histiocytoma.

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either the local invasion or proximity to the vital structures. Radiotherapy due to its cardiotoxicity at radical doses cannot be considered as an optimal therapy for malignant cardiac tumors. The doses that are effective are known to cause cardiomyopathy and chronic radiation pericarditis.8 Chemotherapy also has its limitations such as relatively low response rates. Moreover, doxorubicin, which is an effective chemotherapeutic drug and therefore commonly used for the soft tissue sarcomas, is cardiotoxic, which limits its usage and effectiveness in patients with cardiac sarcomas.9 For patients with unresectable or partially resectable heart sarcomas, radiation and chemotherapy may be used but without great expectation of long term tumor control. Limited evidence shows that selected patients with nonmetastasing MFH can benefit from orthotopic cardiac transplantation.6 Cardiac neoplasms have not been routinely considered for OHT because of concern of tumor recurrence and the possibility that immunosuppression may stimulate further tumor growth. On the other hand, an increasing number of patients with treated malignancies such as Hodgkin’s disease and breast cancer have undergone successful OHT without an increase in primary tumor recurrence.10 In our patient, maximal surgical reduction was performed. Knowing the malignant nature of the patient’s tumor, the decision for cardiac transplantation and adjuvant chemotherapy was made while waiting for the organ. Doxorubicin and ifosfamide were selected for the firstline chemotherapy regimen. Disease stabilization and even partial remission was obtained lasting for approximately 12 months. During second-line chemotherapy, metastasis in the left thigh was noticed, indicating tumor insensitivity to these cytotoxic drugs. A combination of gemcitabine and docetaxel was attempted,11,12 but development of lung embolism and the deterioration of patient’s performance status prevented further application of chemotherapy. The radiotherapy was not applied because of the already mentioned cardiotoxicity. In the case of soft tissue sarcoma, distant spread is by the hematogenous route and lung metastases are the commonest metastatic site followed by bone and liver. Metastases in soft tissue are much rarer, except in alveolar soft part sarcoma. The presented patient during our follow-up has never developed metastases at the lung, bone, or liver. Moreover, the two distant metastases she did develop were both in the skeletal muscles, what is for the soft tissue sarcomas and probably for the heart sarcomas a rather peculiar metastatic sites. Strict follow-up of patients with MFH is mandatory because it has a high rate of recurrence and metastasing. Development of an optimal therapy for MFH will need improved understanding of the natural history and prognostic factors of this very rare disease. Adjunctive chemotherapy in conjunction with resection remains the first-line therapy. The potential gain of radiotherapy must be weighed against the risk of damage to the myocardium and pericardium. The role of cardiac transplantation for primary cardiac MFH should be weighed on a case-by-case basis for patients who present with unresectable tumor and no extracardiac evidence of disease.

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Acknowledgment: This work was partially supported by the Ministry of Science and Technology of the Republic of Croatia (grant no. 0074004 to A.J.).

REFERENCES 1. Butany J, Nair V, Naseemuddin A, et al: Cardiac tumors: Diagnosis and management. Lancet Oncol 2005;6:219228. 2. Sarjeant JM, Butany J, Cusimano RJ: Cancer of the heart: Epidemiology and management of primary neoplasms and metastases. Am J Cardiovasc Drugs 2003;3:407-421. 3. Weiss SW, Enzinger FM: Malignant fibrous histiocytoma: an analysis of 200 cases. Cancer 1978;41:2250-2266. 4. Okamoto K, Kato S, Katsuki S, et al: Malignant fibrous histiocytoma of the heart: Case report and review of 46 cases in the literature. Internal Med 2001;40:1222-1226. 5. Floyd JD, Nguyen DT, Lobins RL, et al: Cardiotoxicity of cancer therapy. J Clin Oncol 2005;23:7685-7696. 6. Gowdamarajan A, Michel RE. Therapy for primary cardiac neoplasms: is there a role for heart transplantation? Curr Opin Cardiol 2000;15:121-125. 7. Shah AA, Chung A, Sbarbaro JA, et al: Malignant fibrous histiocytoma presenting as an atrial myxoma. Cancer 1978;42:2466-2471. 8. Gaya AM, Ashford RF: Cardiac complications of radiation therapy. Clin Oncol 2005;17:153-159. 9. Spira AI, Ettinger DS: The use of chemotherapy in softtissue sarcomas. Oncologist 2002;7:348-359. 10. Goldstein DJ, Oz MC, Rose EA, et al: Experience with heart transplantation for cardiac tumors. J Heart Lung Transplant 1995;14:382-386. 11. Kostler WJ, Brodowicz T, Attems Y, et al: Docetaxel as rescue medication in anthracycline- and ifosfamideresistant locally advanced or metastatic soft tissue sarcoma: Results of a phase II trial. Ann Oncol 2001;12:12811288. 12. Hensley ML, Maki R, Venkatraman E, et al: Gemcitabine and docetaxel in patients with unresectable leiomyosarcoma: Results of a phase II trial. J Clin Oncol 2002;20:2824-2831.

Trans-Aortic Repair of a Sinus of Valsalva Aneurysm Emmanouil I. Kapetanakis, M.D.,∗ Constantinos Ieromonachos, M.D.,∗ George Stavridis, M.D.,∗ Theofani A. Antoniou, M.D.,† George Athanassopoulos, M.D.,‡ Dennis V. Cokkinos, M.D.,‡ and Peter A. Alivizatos, M.D.∗ ∗

First Division of Cardiac Surgery and Transplantation Services, †Department of Cardiac Anesthesiology, and ‡First Cardiology Department, Onassis Cardiac Surgery Center, Athens, Greece

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ABSTRACT Sinus of Valsalva aneurysms are rare and vary in their presentation and approach of surgical repair. We report on a case of isolated right sinus of Valsalva aneurysm that underwent successful excision and patch repair with individual sutures placed through the annulus of the aortic valve. doi:

10.1111/j.1540-8191.2007.00452.x (J Card Surg 2007;22:516-519) First described by Thurnam in 1840, sinus of Valsalva (SOV) aneurysms occur infrequently, accounting for 0.14% to 1.5% of the total cardiac surgical load.1,2 Since the first successful aneurysm repair by Lillehei in 1956, surgical excision and repair has become the accepted standard of care.2 The many types and variations of presentation in unruptured and ruptured SOV aneurysms and their rarity allow for various surgical approaches and repair techniques. This report describes the case of a patient presenting with an acquired SOV aneurysm, which was surgically treated through a modified patch repair using isolated transaortic suture placement. CASE PRESENTATION A 76-year-old man with a history of dyspnea on exertion was found echocardiographically to harbor a moderately large (4.6 cm × 4.4 cm × 4.3 cm) aneurysm of the right SOV, which was protruding and partially occluding his right ventricular outflow tract (Fig. 1). Pressure gradient across the pouch was measured at 58 mm Hg. Chest films revealed slight cardiac enlargement, whereas cardiac catheterization showed mild atheromatosis with no significant stenosis. The patient was referred to our service and was scheduled for elective surgical repair. After induction of anesthesia, a median sternotomy was performed and the patient was placed on cardiopulmonary bypass (CPB) via a two-stage venous outflow and an aortic inflow cannula. Two and a half leters of cold Bretschneider’s HTK solution were administered antegrade and retrogradely for cardioplegic arrest. Routine inspection of the heart and of the great vessels did not demonstrate any significant pathology. A cross-clamp was applied to the ascending aorta, which was entered through a “hockey-stick” incision. A deficit of 2.5 cm in diameter was found in the wall of the right coronary sinus and a sac-like structure protruding into the right ventricle proximally to the pulmonic valve. No ventricular septum defect was identified. The wind sock-like segment was resected, creating an opening in the wall of the right ventricular outflow tract above the right aortic cusp. A 2 cm × 3 cm knitted cloth patch (Hemashield; Boston Scientific Corporation, MA, USA) was used to obliterate the deficit. Continuous 4.0 polypropylene (Prolene; Ethicon, NJ, USA) sutures were used for the superior patch segment, while Address for correspondence: Emmanouil I. Kapetanakis, M.D., Research Fellow, First Department of Cardiac Surgery, and Transplantation Service, Onassis Cardiac Surgery Center, 356 Sygrou Avenue, Athens, Greece, 176 74. Fax: (011-30210)-949-3332; e-mail: emmanouil [email protected]

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single pledgeted mattress sutures were placed transannularly to secure the inferior portion. The isolated sutures were placed from the aortic side towards the pulmonary artery, below the hinge of the right aortic cusp and through the intraventricular septum (Fig. 2). After completion of the patch repair, a two-layer closure of the aorta was performed, the heart was de-aired and the patient was rewarmed. No stenosis or regurgitation was present by transesophageal echocardiography, and the patient was successfully weaned from CPB. He was transferred to the intensive care unit in stable condition, and after an uneventful recovery, he was discharged home on the seventh postoperative day. Now, three months after surgery, he has returned to his usual activities. DISCUSSION The sinuses of Valsalva comprise 3 distinct outpouchings of the aortic root, each being associated with a cusp of the aortic valve. Aneurysmal dilatation of a sinus occurs infrequently and is due to a variety of congenital and acquired causes. Most congenital SOV aneurysms are due to structural deficiencies in the media and absence of normal elastic tissue, causing the separation of the sinus from the media adjacent to the hinge line of the aortic valve cusp.2,3 Acquired SOV aneurysms are marked by degeneration of the media secondary to syphilis, infection, atherosclerosis, and cystic media necrosis.1,2 In our patient, the histopathology examination demonstrated an acquired degenerative cause of origin, presenting with extensive nonspecific myocardial hypertrophy and diffuse fibrotic changes. There was no evidence of active myocarditis, amyloidosis, sarcoidosis, syphilis, or necrotic ischemic changes present. Associated findings to SOV aneurysms often include a ventricular septum defect (VSD), a bicuspid aortic valve, a history of endocarditis, Marfan’s syndrome, infundibular pulmonary stenosis, aortic insufficiency, and/or aortic stenosis.1-4 A gradually dilating SOV aneurysm produces symptoms by compression or direct rupture into an adjacent cardiac chamber.2 Easy fatigability, dyspnea, angina, palpitations, edema, and syncopal episodes are the most common symptoms, which in 50% to 70% of cases occur gradually, usually between 20 and 30 years of age.1,2 Their severity depends on the degree of shunt, regurgitation, associated lesions, and the patient’s age.2 Our patient experienced symptoms of dyspnea on exertion. The presence of symptoms, in conjunction with the evident right ventricular outflow tract obstruction, dictated a surgical intervention. The management of symptomatic, unruptured SOV aneurysms mandates early surgical correction.1 However, because of the rarity and anatomic variability of SOV aneurysm presentation, there is no standardized surgical repair approach. Operative procedures, which have been used with various degrees of success, include direct closure, patch repair, aortic valve replacement/repair and aortic root replacement with reimplantation of the coronary arteries.1,2 Surgical repair

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Figure 1. Echocardiographic image of a right sinus of Valsalva aneurysm protruding and occluding the right ventricular outflow tract. AO = aortic root; RV = right ventricle; AN = aneurysm sac.

by direct closure or patch placement are the techniques most often been used.2,4 In most cases, the aorta is initially opened to check the pathology of the aneurysm and the aortic cusps.4 The protruding aneurysm is excised; in early years, the base of the aneurysm was directly closed by horizon-

Figure 2. Patch repair with isolated trans-aortic placement of sutures.

tal mattress sutures reinforced with Teflon buttresses; however, in later times, because of the possibility of increased recurrence, a knitted Dacron patch using continuous stitches has been used to obliterate the deficit.4 Often, to facilitate repair, a concomitant right ventriculotomy or atriotomy can be performed.2 In this case, standard aortotomy revealed an isolated SOV aneurysm with no associated VSD. Therefore, a concomitant exploratory right ventriculotomy was not performed. Because the posterior border of the deficit, after the sac excision, was located very close to the valvular annulus, we opted to perform a patch repair instead of a plication. Moreover, several studies have suggested that patch closure results in a lower incidence of aneurysmal recurrence.2 To secure the patch’s posterior border, isolated sutures were used instead of a continuous one so as to avoid distortion or plication of the lower segment of the deficit that would otherwise produce a distortion of the right aortic cusp and development of iatrogenic aortic regurgitation (Fig. 2). The location of the deficit and its morphology allowed for the placement of the stitches transannularly facilitated by gently lifting the right aortic cusp. Operative results following SOV aneurysm repair have been excellent with a reported operative mortality of 3.5% to 3.9% and an actuarial 5 years survival of 83.1% to 84.9% approaching that of a healthy population.1,2,4 Most surviving patients are symptom free; however, direct closure has resulted in a 20% to 30% reoperation for aneurysm recurrence.5 Our patient was discharged home in excellent condition and three months later has resumed his previous lifestyle. In conclusion, SOV aneurysms need to be corrected surgically and rather promptly considering the associated morbidity and mortality; however, their anatomical variability and morphology allows for various operative procedures. A repair approach should be carefully se-

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lected after confirming the extent of the lesion and its associated abnormalities during the operation. REFERENCES 1. Takach TJ, Reul GJ, Duncan M, et al: Sinus of Valsalva aneurysm or fistula management and outcome. Ann Thorac Surg 1999;68:1573-1577. 2. Harkness JR, Fitton TP, Barreiro CJ, et al: A 32-year experience with surgical repair of sinus of Valsalva aneurysms. J Card Surg 2005;20:198-204. 3. Naka Y, Kadoba K, Ohtake S, et al: The long-term outcome of a surgical repair of sinus of Valsalva aneurysm. Ann Thorac Surg 2000;70:727-729. 4. Chu SH, Hung CR, How SS, et al: Ruptured aneurysms of the sinus of Valsalva in oriental patients. J Thorac Cardiovasc Surg 1990;90:288-298. 5. Abe T, Komatsu S: Surgical repair and long term results in ruptured sinus of Valsalva aneurysm. Ann Thorac Surg 1988;46:515-519.

A Case of Pneumopericardium Following Endomyocardial Biopsy Turgay Celik, M.D.,∗ Atila Iyisoy, M.D.,∗ Hurkan Kursaklioglu, M.D.,∗ Celalettin Gunay, M.D.,† U. Cagdas Yuksel, M.D.,∗ and Ersoy Isik, M.D.∗ ∗

Department of Cardiology, and †Department of Cardiovascular Surgery, Gulhane Military Medical Academy, School of Medicine, Etlik-Ankara, Turkey ABSTRACT Pneuomopericardium is a very rare condition, less common than isolated pneumothorax or pneumomediastinum. Since it can occasionally cause pericardial tamponade, prompt recognition and treatment of this condition is lifesaving. Up to now only one case of isolated pneumopericardium after endomyocardial biopsy has been reported in a two-month boy with a dilated cardiomyopathy of unknown origin. In the current case, we report a 25-year-old man who underwent orthotopic heart transplantation three years ago in whom isolated pneumopericardium occurred following endomyocardial biopsy performed via right internal jugular vein. doi: 10.1111/j.1540-8191.2007.00453.x

(J Card Surg 2007;22:519-521) Endomyocardial biopsy is currently the accepted method for diagnosing and monitoring cardiac allograft rejection. Biopsy specimens are usually taken from the Address for correspondence: Turgay Celik, M.D., Assistant Professor of Cardiology, Department of Cardiology, Gulhane School of Medicine, 06018 Etlik-Ankara, Turkey. Fax: +90-312-3044250; e-mail: [email protected]

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right ventricular septal wall via right or left internal jugular veins.1 Local complications namely hematoma, local infection, and injury to lung (pneumothorax, hemothorax) and nerve (recurrent laryngeal palsy and Horner’s syndrome) are possible but rarely encountered during vascular access.2 Pneuomopericardium is a very rare entity, less common than isolated pneumothorax or pneumomediastinum.3-5 Since it can occasionally cause pericardial tamponade, prompt recognition and treatment of this condition is life saving. In the current case, we report a 25-year-old man who underwent orthotopic heart transplantation three years ago in whom isolated pneumopericardium occurred following endomyocardial biopsy performed from right internal jugular vein. CASE A 25-year-old man with the history of idiopathic dilated cardiomyopathy who underwent orthotopic heart transplantation three years ago was referred for endomyocardial biopsy to monitor cardiac allograft rejection. After standard preparation and local anesthesia with 2% lidocaine, the right internal jugular vein was punctured with 18-gauge needle, and an 8F short sheath was introduced using standard technique. After repeated attempts, the Stanford-Scolten bioptome was advanced under fluoroscopic guidance across the atrial suture line until its tip lied against the lower third of the lateral right atrial wall. Then bioptome was rotated counterclockwise and simultaneously advanced into the right ventricular cavity. The tip of the bioptome was placed on the interventricular septum and five biopsy specimens were obtained from multiple sites of right ventricle. At the end of the procedure, the patient described sudden onset, sharp and stabbing pain in the left side of chest. The pain increased severely over the course of five minutes. He was taken into the emergency room. In the emergency room, he was stable, with an oxygen saturation of 95% on room air. His blood pressure was 125/80 mm Hg with a pulse of 62 beats/min. Physical examination and resting electrocardiogram revealed normal findings. But, posteroanterior chest radiography in erected position showed the presence of small area of pneumopericardium (Fig. 1), which resolved spontaneously over 24 hours (Fig. 2). He was discharged two days later and was found to be asymptomatic at three-month follow-up visit. DISCUSSION Isolated pneumopericardium, during vascular access via internal jugular, subclavian, or femoral veins is a very rare but a potential life-threatening complication.3,4 Pneumopericardium is usually self-limited and resolves spontaneously, but tension pneumopericardium may lead to cardiac tamponade. Pneumopericardium can occur as a direct complication of any local pericardial inflammatory or neoplastic condition. The most common cause is iatrogenic, either following cardiothoracic surgery or pericardiocentesis.6 Also penetrating chest trauma,7 blunt chest trauma,8 barotrauma from mechanical ventilation, especially in neonates,9 infec-

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Figure 1. Posteroanterior chest radiograph following endomyocardial biopsy shows a continuous thin radiolucent rim of air (arrow) at the base of heart.

tion from gas-forming organisms10 and the presence of an abnormal communication between an air containing anatomic structures and the pericardial sac, e.g., bronchopleural-pericardial fistula. Up to now, only one case of pneumopericardium has been reported as a complication of endomyocardial biopsy in an infant.9 To our knowledge, this is the first reported case of isolated pneumopericardium following endomyocardial biopsy in adults. The diagnosis of pneumopericardium can be easily confirmed by conventional chest radiograph.11 At posteroanterior chest radiography, a continuous thin radiolucent rim of air follows cardiac silhouette and is outlined by a fine line representing the pericardial sac which is referred to as “halo sign” (Fig. 1). In pneumomediastinum, gas does not usually surround the heart completely, is not confined to the region of heart, and can be seen as multiple thin streaks extending to the superior mediastinum and neck. The air was in paracar-

Figure 2. The resolution of air in the pericardial space in posteroanterior chest radiograph obtained from 24 hours later.

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dial location in our case; however, it is usually located at the level of the aorta and pulmonary arteries in pneumopericardium. Although the exact mechanism of the pneumopericardium in our patient is not fully elucidated, we think that it may have been caused by accidental perforation through the wall of the superior vena cava in its intrapericardial tract, allowing migration of air into the pericardium through the weak points in the pericardial reflection over aorta and pulmonary artery.12 Institution of air through dissected adventitia during jugular access could be another mechanism, in which air may migrate to the pericardial region via subadventitial tract. One can claim that, accidental atrial or ventricular perforation may result in pneumopericardium. As far as we know, cardiac perforation can rapidly result in tamponade. In contrast, our patient had small pneumopericardium without impaired cardiac function, which could be managed conservatively. Acute hemodynamic deterioration needs to implement further clinical investigation and cardiac tamponade should be definitely ruled out in patients with pneumopericardium. In tension pneumopericardium, rapid fluid resuscitation combined with pericardiosentesis followed by pericardial fenestration and pericardial drainage should be performed.4 However, our patient showed no hemodynamic embarrassment and was managed conservatively. In conclusion, pneumopericardium as a complication of endomyocardial biopsy is an extremely rare condition that may be quickly diagnosed on a chest radiogram. Cardiologists should be kept in mind pneumopericardium while making differential diagnosis of chest pain and its clinical and radiographic manifestations in a patient undergoing endomyocardial biopsy. REFERENCES 1. Knisely BL, Mastey LA, Collins J, et al: Imaging of cardiac transplantation complications. Radiographics 1999;19:321-339. 2. Shah M: Endomyocardial Biopsy. In: Griffin BP, Topol EJ (eds.). Manual of Cardiovascular Medicine. Philadelphia, Lippincott Williams & Wilkins, 2004, pp 720-724. 3. Brander L, Ramsay D, Dreier D, et al: Continuous left hemidiaphragm sign revisited: A case of spontaneous pneumopericardium and literature review. Heart 2002;88:e5. 4. Capizzi PJ, Martin M, Bannon MP: Tension pneumopericardium following blunt injury. J Trauma 1995;39:775780. 5. Pass RH, Trivedi KR, Hsu DT: A new technique for endomyocardial biopsy in infants and small children. Catheter Cardiovasc Interv 2000;50:441-444. 6. Boyce SH, Corfield AR, McGuffie AC, et al: Spontaneous tension pneumopericardium. Eur J Emerg Med 2004;11:181-184. 7. Demetriades D, Charalambides D, Pantanowitz D, et al: Pneumopericardium following penetrating chest injuries. Arch Surg 1990;125:1187-1189. 8. Gould JC, Schurr MA: Tension pneumopericardium after blunt chest trauma. Ann Thorac Surg 2001;72:1728-1730. 9. el Gamel A, Barrett P, Kopff G: Pneumopericardium: A rare cause of cardiac tamponade in an infant on a positive pressure ventilation. Acta Paediatr 1994;83:1220-1221.

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10. Stridbeck H, Samuelsson L: Pneumopyopericardium. Acta Radiol Diagn (Stockh) 1983;24:305-308. 11. Bejvan SM, Godwin JD: Pneumomediastinum: Old signs and new signs. Am J Roentgenol 1996;166:1041-1048. 12. Sestito A, Sgueglia GA, Infusino F, et al: A 60-year-old man with chest pain following pacemaker implantation. CMAJ 2005;172:874.

Effect of Epicardial Fat on Ablation Performance: A Three-Energy Source Comparison Kimberly N. Hong, M.H.S.A., Mark J. Russo, M.S., M.D., Elyse A. Liberman, B.S., Alex Trzebucki, B.S., Mehmet C. Oz, M.D., Michael Argenziano, M.D., and Mathew R. Williams, M.D. Division of Cardiothoracic Surgery, Department of Surgery, College of Physicians and Surgeons of Columbia University, New York, New York ABSTRACT Objectives: To investigate the effect of epicardial fat on surgical atrial fibrillation ablation performance using an in vitro model. Two tissue models were employed to investigate standard penetration and maximal lesion depth performance of bipolar radiofrequency (RF), microwave, and laser energy sources. Methods: Ventricular veal tissue was utilized in various thicknesses (3 mm, 5 mm, 7 mm, 15 mm). Epicardial fat was modeled by layering porcine fat (1 mm, 2 mm and 4 mm) on moistened tissue. In each group, 8 to 10 lesions were created. Post ablation, tissue samples were sectioned and ablation depth of each myocardial section measured using 1% tetrazolium tetrachloride dye solution. Results: The laser energy source produced nearly 100% transmural lesions in almost all study groups irrespective of myocardium thickness and fat thickness. The microwave device maintained transmurality in all 3mm and most 5-mm myocardium trials but fell to near zero with all 7-mm myocardium trials. The bipolar RF maintained transmurality only when no fat was applied. In the maximal lesion depth models, the laser was capable of producing lesions >8 mm with no fat and >6 mm with either 2 mm or 4 mm of fat present. The microwave produced lesions in the no fat (>6 mm) and 2-mm (>4 mm) fat group. The bipolar RF produced 83% transmurality with no fat and zero percent transmurality with 2 mm of fat present. Conclusions: Epicardial fat can severely limit transmurality in energy sources that utilize conductive heating. Laser energy was

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uniformly superior at producing both transmural and deep lesions irrespective of the presence of fat. doi: 10.1111/j.1540-8191.2007.00454.x

(J Card Surg 2007;22:521-524) Tissue ablation using energy as an alternative to the scalpel has resulted in the resurgence of surgical treatment for arrhythmias, especially atrial fibrillation (AF).1-4 Early in the development of energy sources, ablation was performed primarily by an endocardial approach. Endocardial ablation is easier to perform than epicardial, because during endocardial ablation the field is stationary, empty, and in direct contact with the energy probe.5 Conversely, several factors are postulated to limit the effectiveness of epicardial ablation, including the presence of epicardial fat. Nevertheless, further advances in surgical atrial fibrillation ablation (SAFA) will depend on the refinement of epicardial approaches. Most energy sources work by direct heating from the energy source and conductive heating from the focus of direct energy on the tissue surface. Therefore, epicardial fat effectively limits lesion depth by separating the energy source from the atrial tissue and acting as an insulator of the underlying tissue. The role of fat in the impedance of lesion formation is not well characterized and likely varies with the type of energy due to different tissue interactions specific to each energy source. In this study, using in vitro techniques, we sought to determine the effect of fat on lesion formation with three different epicardial energy sources. METHODS Ventricular tissue from fresh veal hearts, less than 48 hours old and cold preserved, were used for all ablations. A TTC dye assay was performed on all hearts to ensure tissue viability prior to ablation. Ventricular tissue was then sectioned to predetermined thicknesses of 3 mm, 5 mm, 7 mm, and 15 mm as outlined below. Porcine fat was utilized, and similar to the heart tissue, cut into predetermined thicknesses of 1 mm, 2 mm, and 4 mm. All tissue was warmed to 37 ◦ C prior to ablation. The fat was placed directly on the tissue after being moistened with saline to insure a good myocardial/fat interface. The myocardial/fat combination test groups will be consistently referenced by the following convention: myocardium thickness/fat thickness in mm. Each group had between 8 and 10 lesions created. The 3-mm, 5-mm, and 7-mm groups were used to determine individual device effectiveness at creating transmural lesions. The 15-mm tissue groups were used to test for maximum penetration depths using the microwave and laser energies. These lesions were not intended to be transmural, and instead assessed the maximum lesion depth each device achieved on unimpeded and fat-impeded myocardium. A separate Address for correspondence: Mathew R. Williams, M.D., Division of Cardiothoracic Surgery, New York-Presbyterian Hospital/Columbia, Milstein Hospital Bldg Room 7-435, 177 Fort Washington Avenue, New York, NY 10032. Fax: 212-305-2439; e-mail: [email protected]

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TABLE 1 Total Percent Transmural within Test Group by Energy Source Test Group (Myocardium/Fat in mm)

Bipolar RF Microwave Laser

3/0

3/1

3/2

3/4

5/0

5/1

5/2

5/4

7/0

7/1

7/2

7/4

100 100 100

12 95 100

50 100 100

22 0 100

100 90 100

0 80 95

12 70 100

0 5 95

88 55 95

0 12 88

0 0 88

0 0 50

model tested for maximum lesion depths achieved using the bipolar RF device. This model employed two tissue samples placed together to simulate the transatrial clamping used to create lesions. Ablation Lesions were created with the three energy sources using the manufacturers’ recommended parameters for epicardial ablation. The bipolar RF system (Atricure, OH, USA) consisted of an atraumatic clamp with electrodes residing in the jaws of the device. Tissue was placed between the electrodes and the clamp closed. RF energy was delivered until tissue conductance between the electrodes reduced to a steady state for 2 seconds, or the 30-second maximum ablation time was reached (Gillinov 2002). Both microwave and laser systems consisted of a tipped probe that was applied to the tissue with manual pressure. The microwave system (Flex 10, Guidant Corporation, CA, USA) was activated for 90 seconds at 65 W. The laser system (Optimaze, Edwards Lifesciences, Irvine, CA, USA) was activated for 90 seconds at 12 W/cm. Lesion evaluation Upon completing the ablation, incisions perpendicular to the ablated tissue site were created at the midpoint and respective quarter-points of the tissue-probe interface. This resulted in four discrete data points per lesion. The tissue was then placed in a 1% solution of TTC dye for one hour to enable adequate resolu-

tion of viable and nonviable tissue. All lesion depths were measured and recorded using digital calipers. Fat was not included in the measurements, only deactivated myocardium was used to determine the lesion depths. Tissue samples were considered transmural if staining indicated only nonviable tissue remained in the sample. RESULTS The percentages of total transmural lesions within each test group are detailed in Table 1 and shown graphically in Figure 1. Bipolar RF maintained transmurality only in the 3/0 and 5/0 trials. Transmurality dropped significantly in all of the test groups containing fat. Microwave ablation in the 3/1 (95%), 3/2 (100%), 5/1 (80%), and 5/2 (70%) groups had higher rates of transmurality than the RF, although 4 mm of fat impedence reduced transmurality to insignificant levels. When myocardium depth was increased to 7 mm, transmurality dropped to 55% in 7/0 and fell to near zero in groups in which fat of any thickness was applied. Laser energy created 100% transmural ablations in nearly all the trials within the 3-mm and 5-mm test groups. Only in group 7/4 (50%) did the percent transmural drop below 88%. Laser energy was the only energy source where fat thickness did not affect the ability to successfully ablate through the tissue. In the maximal penetration trials, the lesion depths for all the 15-mm groups are shown in Figure 2. These trials demonstrate the maximum depth of unimpeded and fat impeded penetration for the microwave and

Figure 1. Bar graph of total percent transmural within test group by energy source.

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Figure 2. Ablation depth in maximal penetration groups (15 mm) using microwave and laser energy.

laser devices. In all cases, the ablation depth of the laser was significantly deeper than the microwave source (p < 0.001). The double thickness (3 mm + 3 mm) bipolar tissue trials indicated that the bipolar RF device is effective at creating transmural lesions (83%) only when no fat is present. None of the lesions created in the 3 + 3/2 group were transmural. DISCUSSION Findings here suggest that in the presence of varying thicknesses of myocardial tissue and epicardial fat, laser energy source is superior to microwave and bipolar radiofrequency in creating transmural lesions. In the laser groups, myocardial and fat thickness had very little effect and was only appreciable in the 7/4 group (50%). The laser device also produced uniformly deeper lesions than the microwave device in the ablation depth test as seen in Figure 2. The radiofrequency device was capable of producing 100% transmurality in the 3-mm and 5-mm myocardial groups with no fat, but layering fat on and increasing thickness of myocardium appeared to be significant barriers to achieving transmural lesions. Microwave energy proved more capable within the 3-mm and 5-mm myocardium groups, especially with fat up to 2 mm thick. However, at 4 mm of fat, the microwave device was unable to reach transmurality, signaling a limit to its effectiveness at achieving adequate ablative temperatures when significant fat buffers are present. The laser device proved capable of producing transmural lesions in almost 100% of all 3-mm and 5-mm myocardium trials and maintained above 85% transmurality in three of four trials in the 7-mm myocardium group. Generally, microwave ablation demonstrated greater control over lesion formation with narrower and deeper lesions than radiofrequency. This was demonstrated in the 15-mm ablation depth test in which the microwave produced ablations of considerable depth (6

mm with no fat and 4 mm with 2 mm of fat). As myocardium thickness increased to 7 mm, transmurality fell significantly, especially when fat of any thickness separated the device from the myocardial tissue. Thus, there seemed to be a marked improvement over the radiofrequency device in achieving transmurality with varying tissue thickness. Yet, there was a tissue thickness limit wherein ablation performance significantly decreased. This was likely related to a reduction in the conductive heating as tissue thickness increased. These observations may reflect the properties of the various energy sources. With RF and microwave, resistive heating is limited to 1 mm below the device tissue interface. Conversely, laser energy penetrates deeper beyond the device tissue interface. In fact, absorption of actual laser energy is as deep as 4 mm into the tissue. Therefore, while RF and microwave energy rely largely on conductive heating to ablate tissue, in laser ablation conductive heating contributes less to the overall heating mechanism. Moreover, in a previous diagnostic study of the laser device, it was determined that the extinction coefficient for laser energy in myocardium is greater (0.27) than in fat (0.04).6 Extinction coefficient refers to the amount of energy absorbed for a particular wavelength; thus, the larger myocardial extinction coefficient indicates that rather than being dissipated into fat tissue, more of the laser energy is absorbed into the myocardium.

LIMITATIONS It should be emphasized that because we used an in vitro model, the composition of the tissue used in our study may differ from that found in in vivo tissue, thus compromising the generalizability of these results. However, as mentioned earlier, we attempted to replicate conditions as close to those found in vivo by first using only viable tissue less than 48 hours old. Additionally, all tissue was stored in air-tight containers to

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minimize dehydration, and then reheated to 37 ◦ C prior to ablation. As with all manual devices, the depths of the lesions created will vary with operator skill and technique. Specifically, because RF and microwave energies rely on conductive heating via the tissue-probe interface, variability in manual pressure exerted on the probe effects the diffusion of heat and disruption of tissue viability. There are currently RF devices that apply a uniform pressure across the tissue-probe interface with the intent of reducing this variability. Because of the deeper absorbance of laser energy, and less dependence on heat transfer via the tissue probe interface, manual pressure will contribute less to variability in device effectiveness. CONCLUSION Findings here suggest that in the presence of varying thicknesses of myocardial tissue and epicardial fat, the laser energy source is superior to microwave and bipolar radiofrequency in creating transmural lesions. These observations may reflect the laser devices deeper penetrance, decreased reliance on conductive heating, and lower fat extinction coefficient. REFERENCES 1.

Cox JL, Schuessler RB, Lappas DG, et al: An 8-1/2 year clinical experience with surgery for atrial fibrillation. Ann Surg 1996;224:267-275. 2. Cox JL: Atrial fibrillation II rationale for surgical treatment. J Thorac Cardiovasc Surg 2003;126:1693-1699. 3. McCarthy PM, Gillinov AM, Castle L, et al: The Cox-Maze Procedure: The Cleveland Clinic experience. Sem Thorac Cardiovasc Surg 2000;12:25-29. 4. Kosakai Y: Treatment of atrial fibrillation using the Maze Procedure: The Japanese experience. Sem Thorac Cardiovasc Surg 2000;12:44-52. 5. Garrido MJ, Williams M: Mimimally invasive surgery for atrial fibrillation: Toward a totally endoscopic, beating heart approach. J Card Surg 2004;19:216-220. 6. Williams M: Edwards Optiwave 980 Epicardial Encircle Device. College of Physicians and Surgeons of Columbia University, 2005.

Emergency Endovascular Stent Graft Repair of Aorto-Bronchial Fistulas Postcoarctation Repair Anand Sachithanandan, A.F.R.C.S.I.,∗ Ian McCafferty, F.R.C.R.,† Peter Riley, F.R.C.R.,† Robert S. Bonser, F.R.C.S. (C.Th).,∗ and Stephen J. Rooney, F.R.C.S. (C.Th).∗ ∗

Departments of Cardio Thoracic Surgery and †Interventional Radiology, Queen Elizabeth Hospital, Birmingham, England, United Kingdom

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ABSTRACT Cardiovascular complications following coarctation repair include aorto bronchial fistulas (ABF) which if untreated are invariably fatal. Reoperative surgery is associated with considerable mortality and morbidity. Endovascular stent aortoplasty provides a relatively new and viable alternative. Two cases of ABF post coarctation repair that presented with life threatening haemoptysis are discussed. Endovascular repair appears safe and feasible in an emergency and may become the preferred treatment modality in such cases. doi:

10.1111/j.1540-8191.2007.00456.x (J Card Surg 2007;22:524-526) Aorto-bronchial fistulas (ABF) as a late complication of coarctation repair, are universally fatal if untreated.1 Surgical treatment is technically difficult and carries significant risk of mortality and morbidity. We report two cases of ABF complicating previous coarctation repair treated by endovascular stent aortoplasty. CASE REPORTS Case 1 A 39-year-old male patient presented with a threeweek history of haemoptysis. In infancy he underwent a left thoracotomy for ligation of a patent ductus arteriosus and pulmonary artery (PA) banding to manage a ventricular septal defect (VSD). He had further surgery at age 13 years, for removal of the PA band following spontaneous VSD closure, repair of a patent foramen ovale, and release of right ventricular outflow tract obstruction with patch repair, performed via a median sternotomy. A week later he had a second thoracotomy for a Dacron patch coarctation repair. He remained well until his current admission to a district general hospital with a modest haemoptysis. Bronchoscopy did not identify the bleeding source and no endobronchial lesion was identified. A spiral enhanced computed tomography (CT) thorax scan demonstrated a saccular aneurysm arising from the lateral descending aorta distal to the arch projecting into the left lung apical subsegmental bronchi. A patchy left upper lobe ground glass appearance consistent with alveolar hemorrhage was noted. He was transferred to our institution urgently for treatment. On transfer he had a further episode of major haemoptysis (500 ml). A Medtronic TALENTTM TAA (Medtronic Ave Santa Rosa, CA, USA) 24 mm × 100 mm thoracic stent was deployed via the left common femoral artery (CFA). Completion angiography confirmed exclusion of the aneurysm with a well-positioned stent, the bare segment covering the left subclavian artery (SCA) (Fig. 1). The procedure was complicated by avulsion of the left external iliac artery on removal of the deployment device, treated with an iliofemoral bypass. His recovery was uneventful and he was discharged from the inAddress for correspondence: Stephen J. Rooney, F.R.C.S. (C.Th), Department of Cardio Thoracic Surgery, Queen Elizabeth Hospital, Birmingham B15 2TH, United Kingdom. Fax: 0121-6272542; e-mail: [email protected]

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Figure 1. Angiography demonstrating placement of endovascular stent across aneurysmal segment with associated aorto-bronchial fistula.

tensive therapy unit the next day. Surveillance CT scan on the seventh postoperative day confirmed successful exclusion of the pseudoaneurysm with no endoleak. At discharge he had excellent peripheral limb pulses and no further haemoptysis. On follow-up at six months he remains well with a normal white cell count, C-reactive protein (CRP), and satisfactory CT scan appearance.

Case 2 A 49-year-old male patient presented to another institution with minor haemoptysis. CT thoracic scan showed bi-basal atelectasis and he was discharged home on oral antibiotics. The patient had undergone patch repair of coarctation at age 21 years. He represented with massive haemoptysis and a further CT scan revealed an irregularity of the lateral aortic wall at the junction of the arch and descending aorta corresponding to the previous repair site with an adjacent pulmonary opacity just distal to the origin of the left SCA. A Medtronic TALENTTM TAA (Medtronic Ave Santa Rosa) 36 mm × 100 mm endovascular thoracic stent was deployed uneventfully via the right CFA. He was extubated at four hours and CT aortogram on the sixth postoperative day confirmed a well-positioned stent with a patent left SCA and no signs of an endoleak. This patient was readmitted three weeks later with an ischaemic left arm. CT aortogram revealed thrombosis of the proximal 1 to 2 cm of the left SCA with the proximal covered stent partially encroaching the ostium of the left SCA. He underwent a carotid-subclavian bypass with a Dacron graft. On follow-up a year later he remains well with a normal white cell count, CRP, and satisfactory CT scan appearance.

DISCUSSION Cardiovascular complications following repair of aortic coarctation include recoarctation, aneurysm formation, aortic dissection or rupture, and endocarditis. As aortic aneurysms may develop in up to 9% of patients late after surgery for coarctation repair, longterm surveillance is mandatory.2 Repeat surgery including that for ABF formation is associated with high in-hospital mortality and includes a morbidity risk of paraplegia.1,3 Reported mortality for surgical treatment of ABF is 15.3%.4 Predictors of local aneurysmal formation after surgical coarctation repair include advanced age (beyond 13.5 years) at index repair and the patch graft technique.2 ABF is a rare complication of thoracic aortic surgery. Foreign body reaction to prosthetic graft and suture material, tracheobronchial compression necrosis, pulsatile pressure necrosis and localized pulmonary infection have all been implicated in the pathophysiology of fistula formation.1 Both our patients presented with life-threatening haemoptysis due to a local aortic aneurysm following previous coarctation repair with erosion into the bronchial tree. Both were successfully treated and remain well at 6 and 12 months follow-up. Importantly the finding of a normal CRP at follow-up suggests no graft contamination and may portend a good long-term outcome. Endovascular stent aortoplasty is however a developing therapy and its overall role in the treatment of ABF is not yet clearly defined. Preservation of aortic integrity by an endovascular approach rather than surgery has been shown to protect the spinal circulation and minimize neurological events.5,6 Theoretical advantages of endovascular stent repair over open repair include less pain, earlier mobilization, and shorter

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hospital stay. If long-term follow-up confirms satisfactory midterm results as reported, endovascular stent aortoplasty will become the treatment of choice for such lesions. CONCLUSION Endovascular stent aortoplasty of an ABF complicating local aneurysm formation post coarctation repair can produce satisfactory medium term results; however, long-term follow-up of such patients is mandatory.

REFERENCES 1. Macintosh EL, Parrott JC, Unruh HW: Fistulas between the aorta and tracheobronchial tree. Ann Thorac Surg 1991;51:515-519. 2. Von Kodolitsch Y, Aydin MA, Koschyk DH, et al: Predictors of aneurysmal formation after surgical correction of aortic coarctation. J Am Coll Cardiol 2002;39:617624. 3. Favre JP, Gournier JP, Adham M, et al: Aortobronchial fistula: Report of three cases and review of the literature. Surgery 1994;115:264-270. 4. Piciche M, De Paulis R, Fabbri A, et al: Postoperative aortic fistulae into the airways: Etiology, pathogenesis, presentation, diagnosis, and management. Ann Thorac Surg 2003;75:1998-2006. 5. Ince H, Petzsch M, Rehders T, et al: Percutaneous endovascular repair of aneurysm after previous coarctation surgery. Circulation 2003;108:29672970. 6. Ince H, Nienaber CA: The concept of interventional therapy in acute aortic syndrome. J Card Surg 2002;17:135-142.

Surgical Intervention to Remove an Entrapped Fractured Guidewire during Angioplasty Ahmad K. Darwazah, Ph.D., F.R.C.S.,∗ Raed A. H. Abu Sham’a, M.D.,† Izzedin H. Yassin, M.R.C.P.,† and Ismail Islim, M.D., M.R.C.P.† ∗

Departments of Cardiac Surgery and †Cardiology, Makassed Hospital, Jerusalem, Israel ABSTRACT Intra-coronary entrapment of angioplasty hardware is a rare complication of coronary intervention. Such complication is potentially dangerous. We present two cases of an entrapped fractured guidewire during angioplasty. They were managed by urgent coronary bypass.

doi: 10.1111/j.1540-8191.2007.00462.x (J Card Surg 2007;22:526-528)

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INTRODUCTION Entrapment of hardware materials of angioplasty inside coronary vessels is rare. Its incidence varies from 0.2% to 0.8%.1 A variety of hardware materials have been reported, such as guidewires, balloons, and angiographic catheters. These materials can cause endothelial injury and thrombosis. Removal of such materials either percutaneously or surgically is mandatory. CASE 1 A 59-year-old diabetic and hypertensive woman admitted for evaluation of her recurrent chest pain. She had coronary artery disease 5 years ago, when she underwent cardiac catheterization and stenting of proximal left anterior descending artery (LAD). Since then, she had been asymptomatic. Eight months earlier, she started to experience typical anginal pain and dyspnea. Upon admission, cardiac catheterization showed 20% stenosis distal to previous stent, 70% lesion in mid LAD, a 99% proximal stenosis of circumflex artery, and 60% stenosis in mid right coronary artery (RCA). A decision was made to perform angioplasty starting with the circumflex artery. A Metronic AVE guidewire (180 cm 0.014”) was introduced across the lesion which was successfully dilated. Subsequently, an R stent (Prodigy) 2.75 mm in diameter with 15 mm length (ORBUS Medical Technology, Ft. Lauderdale, FL USA) was deployed. During removal of the guidewire, some difficulty was encountered. Slight tension was applied; the inner part of the wire fractured and came out leaving the outer cover anchored to the stent (Fig. 1-B). Several trials were made to retrieve the wire by gooseneck snare but without any success. Using a standard cardiopulmonary bypass (CPB), a midline aortotomy was performed. The retaining wire was seen coming out from the left coronary orifice (Fig. 1-C). The proximal part of the wire was removed. Gentle traction of the distal part was done with difficulty, then a decision was made to cut the remaining wire, leaving the part attached to the stent. Subsequently bypass graft to circumflex, LAD and RCA was performed. The patient had an uneventful recovery and was discharged on the 5th postoperative day. CASE 2 A 60-year-old male diabetic and hypertensive patient was admitted for elective cardiac catheterization. Two months earlier, the patient had an attack of burning pain in both upper limbs. Electrocardiogram showed an inversion of T wave in V1-V5 leads. He subsequently had intravenous nitroglycerine and heparin. Since the attack and his recent admission, he was asymptomatic. During catheterization, a diseased LAD was found very close to a second diagonal artery. A decision was made to perform angioplasty to LAD. Address for correspondence: Ahmad K. Darwazah, Ph.D., F.R.C.S., Cardiac Surgery Department, Makassed Hospital, Mount of Olives, P.O. Box 19482, Jerusalem 22110, Israel. Fax: 00972 2 6288392; e-mail: [email protected]

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Figure 1. (A,B) The circumflex coronary artery lesion and the retained guidewire after fracture. (C) Aortotomy showing retained wire coming out from left coronary ostia. (D) The removed guidewire, showing the outer part of the wire which was retained and removed surgically.

Two high-torque floppy guidewires (ASAHI INTECC Co. LTD, Nagoya, Japan) 180 cm, 0.014” were used. The first was introduced into the diagonal artery for protection, while the second wire crossed the LAD lesion. A 2.5-mm balloon (ACS Rx LIFESTREAM (Temecula, CA, USA)) was inflated for 1 min at 8 atmospheres. A residual narrowing was noticed. A bigger balloon (3 mm) was used. During second inflation, a sudden attack of chest pain associated with ST-segment eleva-

tion and ventricular tachycardia occurred. Occlusion of the diagonal artery by thrombus was noticed. A trial to pass a balloon into the diagonal artery failed. Proximal propagation of thrombus toward LAD was seen. A quick decision was made to remove the wire. Unfortunately, it was fractured leaving part of it inside the diagonal artery (Fig. 2). The patient was urgently transferred to surgery due to hemodynamic instability. Using CPB, the diagonal artery appeared cord-like and bluish.

Figure 2. (A-C) Angioplasty of mid LAD. (D) Occlusion of Diagonal artery and retaining part of the guidewire after being fractured (arrow).

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A big thrombus was removed after opening the artery; the thrombus was found extending to the LAD. The retaining wire was seen entangled inside the artery. The whole wire was removed through aortotomy incision. Then both LAD and diagonal arteries were grafted. Several attempts were made to come off bypass but without success, in spite of inotropes and intra-aortic balloon pump. The patient died of low cardiac output. DISCUSSION Percutaneous coronary angioplasty is an effective method used for the treatment of coronary artery disease. However, it carries serious complications in 1.4% of patients,2 such as prolonged angina, myocardial infarction and coronary occlusion, dissection, spasm, and perforation. Entrapment of hardware materials of angioplasty such as guidewires, balloon catheters, and angiographic catheters have been reported in 0.2% to 0.8% of cases.1,3 Under rare circumstances, an entrapped guidewire may fracture.3-6 The exact cause of fracture is not known. Incorrect manipulation especially in tortuous vessels and manufacture defects can be involved.4 In our cases, anchoring of the wire to the deployed stent and rough manipulation were the cause of such fracture. Management of retained hardware can be performed either percutaneously or by surgery. The approach of management was suggested by Chang and coworkers; they recommend an initial management by percutaneous means. If this method fails, surgery should be anticipated. Percutaneous retrieval can be performed by different techniques. The gooseneck snare, two-wire technique, 6 Fr biopsy forceps, and additional angioplasty wire together with balloon catheter have been successfully used.6 Use of the above techniques can be difficult, time consuming, and can further damage the vessel causing dissection and thrombosis. They should be used cautiously, and if difficulties are encountered, surgery should be performed. Surgery was used in our two cases. Percutaneous retrieval failed in the first case, while in the second patient, there was no time due to hemodynamic instability. Wire removal can be done through arteriotomy of the affected vessel. However, when the wire extends to the aortic root, as in our two cases, it has to be removed through a small aortotomy incision. The whole wire has to be removed as retaining part may precipitate thrombus formation.3 In our first case, removal of the whole wire was difficult. It was pulled as much as possible and trimmed. This method has been recommended by Chang and his colleagues.3 Fifty percent of the entrapped wires were treated surgically.1 Removal of the wires with subsequent revascularization was successful in all previously reported cases.3-6 This is not always true. Our second patient died due to perioperative infarction due to development of thrombosis. The cause of such a catastrophic incident presumably results from excessive manipulation. From the above cases, we conclude that an entrapped fractured guidewire is a dangerous complica-

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tion of PTCA. Tortuous vessels and rough manipulations are the main reason for its occurrence. Attempts to remove the retained wire percutaneously should be done carefully without excessive manipulation. Early surgical intervention is an alternative option used in difficult cases. REFERENCES 1. Hartzler GO, Rutherford BD, McConahay DR: Retained percutaneous transluminal coronary angioplasty equipment components and their management. Am J Cardiol 1987;60:1260-1264. 2. Dorros G, Cowley M: Complications Associated with PTCA. In Ischinger T (ed): Practice of coronary angioplasty, 1st Ed. Berlin/Heidelberg: Springer-Verlag, 1986, pp. 223-240. 3. Chang TT, Pellergrini D, Ostrovsky A, et al: Surgical management of entrapped percutaneous transluminal angioplasty hardware. Tex Heart Inst J 2002;29:329-332. 4. Stellin G, Ramondo A, Bortolotti U: Guidewire fracture: An unusual complication of percutaneous transluminal coronary angioplasty. Int J Cardiol 1987;17:339-342. 5. Khonsari S, Livermore J, Mahrer P, et al: Fracture and dislodgement of floppy guidewire during percutaneous transluminal coronary angioplasty. Am J Cardiol 1986;58:855856. 6. Patel T, Shah S, Pandya R, et al: Broken guidewire fragment: A simplified retrieval technique. Catheter Cardiovasc Interv 2000;51:483-486.

Mechanical Prosthetic Valve Dysfunction Causing Pulsus Alternans Leading to Intermittent Electromechanical Dissociation: A Case Report and Literature Review Vasha Kaur, M.B.Ch.B. (Hons), Martyn N. N. Robertson, and Vipin Zamvar, F.R.C.S. C.T.S. Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh, Scotland EH 16 4SA ABSTRACT We describe a case of electromechanical dissociation (EMD) in a 62-year-old female patient following insertion of a Medtronic Hall mitral valve prosthesis. She initially developed pulsus alternans which led, over a few hours, to intermittent electromechanical dissociation. Clinical and echocardiographic findings are described. Emergency surgical intervention revealed a piece of chorda wedged between the disc occluder and the valve ring. This case illustrates clinical and Doppler echocardiographic features associated with a rare presentation of an unusual perioperative complication of prosthetic mitral valve dysfunction. We

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have also included a brief review of related literature. doi: 10.1111/j.1540-8191.2007.00459.x (J

Card Surg 2007;22:528-532) INTRODUCTION Obstruction of a prosthetic valve may be caused by malfunction of the valve mechanism,1 or be related to extrinsic factors.1 The latter has a documented incidence of 0.24%2 in mitral valve replacements and may be caused by remnants of the mitral apparatus. We report a case of acute obstruction of a Medtronic Hall mechanical prosthesis occurring in the immediate postoperative period due to the above mechanism. This case is unusual in the way the obstruction presented - pulsus alternans which led, over a few hours, to intermittent electromechanical dissociation (EMD). The intermittent obstruction was demonstrable with transthoracic echocardiography. CASE REPORT A 62-year-old female patient with rheumatic mitral valve stenosis underwent elective mitral valve replacement. She was in sinus rhythm and had no other past medical history of note. She had severe stenosis with a mitral valve area of 2.0 cm1 . Both anterior and posterior leaflets were thickened and there was severe calcification in the region of the posterior-medial commissure. There was significant thickening of the sub-valvular apparatus as well. Both valve leaflets were excised and the chordae divided at the junction with the papillary muscle. A size 27-m Medtronic Hall (Medtronic, Inc., Minneapolis, MN, USA) tilting disc mechanical prosthetic valve was implanted in the mitral position. The valve was orientated such that the larger orifice was posterior. The initial postoperative period was uneventful, and the patient was extubated at six hours. However, at 10 hours postprocedure, she developed pulsus alternans. Every second pulse was weak in the presence of a normal sinus rhythm. The attending medical and nursing staff did not appreciate the significance of this sign. She remained hemodynamically stable, with a mean blood pressure of 80 mmHg, good urine output, and warm peripheries. The next morning, at 20 hours postprocedure, the missed arterial traces became more frequent with three out of four beats being missed (Fig. 1). A diagnosis of obstruction of the mitral valve leaflet was made and arrangements were made to take the patient back to the surgical theatre for re-exploration. While awaiting transfer to the theatre, a transthoracic echocardiogram was performed. This demonstrated that the valve opened intermittently, coinciding with the maximal arterial pressure on the monitor. When the valve did open, it opened completely. Doppler echocardiography displayed intermittent transmitral flow corAddress for correspondence: Mr. Vipin Zamvar, Consultant Cardiothoracic Surgeon, Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh, Scotland EH 16 4SA. Fax: 0044 131 2423930. E-mail: [email protected] No sources of funding were involved in the production of this article.

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responding to those beats when the valve opened (Fig. 1). On the way to the theatre, she began to deteriorate rapidly, with the valve opening every seventh or eighth beat. She was expeditiously put on cardiopulmonary bypass. On exploring the mitral valve, a piece of chorda was found wedged between the disc and its housing, in the region of the postero-medial commissure. This was obstructing the disc mechanism. The valve was prised open, rotated, and the offending piece of chorda excised. On inspection of the valve at this stage, it was seen to open freely and function normally and was therefore left in situ. The patient was weaned off bypass uneventfully and went on to make uneventful progress with no further episodes of pulsus alternans, electromechanical dissociation or valve dysfunction either clinically or echocardiographically. She was discharged home on the 10th postoperative day. At her two-year followup, she remained well—New York Heart Association (NYHA) Class I, asymptomatic, and in sinus rhythm. DISCUSSION Pulsus alternans was first described in 1872 by Traube. It is characterized by regular alternate beat variation that is weak and strong. It is usually seen as a feature of advanced myocardial disease and is attributed to prolonged metabolic recovery time of damaged myocardium, or alternating contractile failure of some myocardial segments.3 Alternating good and poor filling of the ventricles can also be due to alternating atrial electromechanical dissociation,3 or a malfunctioning prosthetic mechanical mitral valve4 , and this can give rise to pulsus alternans. Electromechanical dissociation occurs when there is no effective mechanical cardiac output despite the presence of normal or near-normal electrical activity. It has been seen after electrical resuscitation from a prolonged cardiac arrest, cardiac tamponade from hemopericardium, pulmonary embolism, and has also been described with mechanical prosthetic valve dysfunction.5 When a prosthetic mitral valve disc is obstructed, the valve does not open and hence there is no or little antegrade filling of the ventricles, resulting in pulseless or near pulseless cycles. The left atrium will continue to fill and the consequential increase in left atrial pressure then forces the disc to open fully with the next beat resulting in near normal stroke volume for that cycle. This results in alternating ventricular filling, and hence alternating stroke volume reflected as pulsus alternans. As the obstruction becomes more severe, the discs stay jammed for longer, requiring three or four or even more cardiac cycles, to generate sufficient pressure in the left atrium to overcome the obstruction and force the discs open. This causes the phenomena of intermittent electromechanical dissociation. To the best of our knowledge, this is the first documented case of a patient with an obstructed prosthetic mitral valve leaflet, presenting as pulsus

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Figure 1. Intermittent electromechanical dissociation: only one of three or four beats is associated with a normal arterial trace. In the intervening beats, the arterial pulse is either very weak, or absent. The patient is in sinus rhythm.

alternans, which gradually led on to intermittent electromechanical dissociation. Prosthetic mitral valve obstruction presenting as either pulsus alternans or electromechanical dissociation is very rare, and reports in the literature are mainly confined to case reports.1,2,4–7,8–12 From the literature we reviewed (Table 1), the time of presentation is variable and can perhaps be divided into three broad categories—occurring hours postoperative, weeks later, or up to 10 years later. All patients were investigated noninvasively with echocardiographic studies that included transthoracic echocardiography, Doppler studies, and/or transoesophageal echocardiography. In two cases, the patients were also investigated with other noninvasive tests, namely phonocardiography6 and fluoroscopic and hemodynamic studies.7 All except one report5 were associated with a single tilting disc valve. In patients with a single tilting disc valve, this complication constitutes a surgical emergency, as progression of the obstruction can lead to an immobile valve and subsequent cardiac arrest. This is evident from the Mok et al.8 case report in which a patient presenting with electromechanical dissociation eight hours postoperatively did not respond to resuscitative efforts and an obstructed mitral valve was discovered at autopsy. In contradiction to the above case, however, in two case reports,8,9 the valve obstruction resolved spontaneously. In both cases, the obstruction was presumably caused by suture debris or mitral remnants that probably broke off due to repeated trauma, thus no longer causing an obstruction to the disc. Another possibility is that the obstruction may have been caused by a thrombus that spontaneously resolved. In the first of these two cases,8 the patient did not receive any surgery and is reported to be doing well at longterm follow-up. The other patient subsequently refused surgery and long-term follow-up is not mentioned in the report.9

In three reports,7,10,11 the obstruction was caused by thrombus formation adjacent to the valve—in the first case7 the thrombus was attached to the explanted valve and hence was surgically removed. In the second,10 the patient’s symptoms responded to intravenous streptokinase precluding the need for surgery. In the third,11 EMD resolved with thrombolytic therapy—recombinant tissue-type plasminogen activator (rt-PA) and intravenous heparin but the obstruction persisted, necessitating the need for surgical intervention and valve replacement. Of the eleven patients who required surgery, seven, including our patient, had a piece of chorda wedged between the disc and the valve housing causing an obstruction. In four of these patients, including our patient, the valves functioned normally once the chordal tissue was excised.1,5,12 The other three patients, all from a single report, received valve replacements.2 There is no definite evidence to support one or the other management choice, and currently the choice is most likely determined both by patient characteristics and surgeon’s preference. Three patients had an obstruction occurring secondary to fibrin ingrowth involving the mitral orifice.4,6,11 All three cases occurred a decade after insertion of the original valve and in one case the fibrinous tissue was also associated with a thrombus formation.11 All three of these patients received replacement valves, which would seem to be the most sensible management option as attempting to remove all the fibrous tissue to keep the valve in situ would be a futile effort and would put the patient at risk of future thromboembolic complications. Of the eleven patients requiring surgery, seven received replacement valves. Five of these were with bileaflet valves2,7,11 while one patient received a ball valve.6 One study did not state the type of valve implanted.4 Bileaflet valves have a lower incidence of block as their valvular mechanism fits within the

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TABLE 1 Summary of Case Reports Describing Prosthetic Mitral Valve Obstruction Presenting as either Pulsus Alternans or Intermittent Electromechanical Dissociation or both Author, Valve Type, Patient Details

Time of Presentation Hemodynamic Sign

Sante,2 Single leaflet, 3 pts—52 6 hrs, 7 hrs, 8 hrs M, 45 M, 42 F Intermittent EMD Hrs Keeble,9 Single leaflet, 74 M Intermittent EMD Our Case, single leaflet, 62 F 10 hrs Pulsus alternans leading to intermittent EMD Shah,5 Single leaflet, 36 M 20 hrs Intermittent EMD 3 weeks Kapoor,13 Single leaflet Intermittent EMD Greenwood,1 Single leaflet, 10 weeks 59 M Intermittent EMD Garg,10 Single leaflet 4 months Intermittent EMD Abu-Ful,7 Single leaflet, 26 M Years Right-sided pulsus alternans Thatai,11 Single leaflet Jortner,4 Single leaflet, 54 F Veenendaal,6 caged ball, 39 F Delgado,12 Single leaflet, 32 M

9 years Pulsus alternans 10 years Pulsus alternans 10 years Pulsus alternans 10 years Intermittent EMD

Investigations Cause of Obstruction

Management

TOE Chordal tissue Tt echo, Doppler, possibly debris, mitral remnant Tt echo, Doppler Chordal remnants

Emergency surgery—valve replacement Spontaneous resolution

Echocardiography Chordal tissue Chordal tissue

Emergency surgery—chordal excision Emergency surgery—excised

Emergency surgery—excision of tissue

Tt echo, Doppler Emergency surgery—chordal Chordal tissue excision Echocardiograph Spontaneous resolution Filamentous structure Tt echo, Doppler, fluoroscopy, Surgery—valve replacement hemodynamic studies Thrombus IV STK Tt echo, Doppler, TOE Fibrous tissue Echo, phonocardiography Fibrous tissue Tt echo, Doppler, TOE Thrombus & fibrous tissue

Emergency surgery—valve replacement Emergency surgery—valve replacement rt-PA, heparin, urgent surgery—valve replacement

Pts = patients; M = male; F = female; hrs = hours; TOE = tranoesophageal echocardiography; Tt echo = tranthoracic echocardiography; IV STK = intravenous streptokinase; rt-PA = recombinant tissue-type plasminogen activator.

prosthetic ring.2 However, leaflet obstruction can occur with bileaflet valves as well. This usually does not constitute as critical an emergency as a single leaflet valve obstruction. Masiello et al.14 described four cases of one leaflet immobilization after mitral valve replacement with Carbomedics (Sulzer, Carbomedics, Austin, TX, USA) bileaflet valves. One case was diagnosed incidentally six days after surgery and resolved spontaneously. The other three cases were detected by intraoperative transoesophageal echocardiogram and necessitated reorientation of the valves. Orientation of the Medtronic Hall valve may play a role in this complication.12 When the major orifice is directed posteriorly, any free chordae would fall inside the angle through which the disc occluder traverses. The disc occluder can scoop the chordae, during systole, up against the metal housing. Once the chordae are caught between the disc and the valve ring, the disc can become tightly shut. When the major orifice is directed anteriorly, the chances of free chordae getting stuck would decrease.

CONCLUSION This is a rare complication of mitral valve replacement with single disc prosthesis. This complication

can be avoided by carefully ensuring removal of all free chordae at the time of surgery and ensuring that there are no free intracardiac suture material obstructing the valve. When chordae are preserved, it is better to orientate the Medtronic Hall valve, so that the major orifice is directed anteriorly. Presence of pulsus alternans or intermittent electromechanical dissociation after a single disc prosthetic mitral valve replacement, should lead to suspicion of valve obstruction. These hemodynamic patterns can occur with mitral valve obstruction even up to 10 years after implantation. Appropriate investigations such as echocardiographic studies can provide confirmatory evidence of the obstruction and plans for emergency surgery should be undertaken. REFERENCES 1. Greenwood JP, Nolan J, Mackintosh AF: Late, intermittent obstruction of a mitral prosthesis by chordal remnants. Eur J Cardiothorac Surg 1997;12(5):804-806. 2. Sante P, Renzulli A, Festa M, et al: Acute postoperative block of mechanical prostheses: Incidence and treatment. Cardiovasc Surg 1994;2(3):403406. 3. Verheugt FWA, Schek H, Meltzer RS, et al: Alternating atrial electromechanical dissociation as contributing factor for pulsus alternans. Br Heart J 1982;48:459461.

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4. Jortner RT, Rafaelof B, Tunick PA, et al: Pulsus alternans as a sign of prosthetic valve dysfunction. Am Heart J 1994;127:221-224. 5. Shah D, Vijaykumar M, Chandrasekhar K, et al: Periodic intermittent electromechanical dissociation: Hemodynamic correlate of a malfunctioning mechanical prosthetic valve. Cathet Cardiovasc Diagn 1996;38:377-378. 6. Veenendaal M. Nanda NC: Noninvasive diagnosis of mitral prosthesis malfunction. Am J Med 1980;69:458– 462. 7. Abu-Ful A, Ilia R, Henkin Y: Right-sided pulsus alternans in prosthetic mitral valve thrombosis. J Invasive Cardiol 2004;16(4):213-214. 8. Mok CK, Cheung LC, Chiu CSW, et al: An unusual lethal complication preservation of chordae tendinae in mitral valve replacement. J Thorac Cardiovasc Surg 1988;95(3):534-536. 9. Keeble W, Cobbe SM: Pressure damping, a “billowing” septum, and an eerie silence: Perioperative, intermittent obstruction of a mitral valve prosthesis. Heart 2000;84(3):e6. 10.Garg NK, Kapoor A, Sinha N: Intermittent electromechanical dissociation due to mechanical prosthetic valve dysfunction. J Heart Valve Dis 2000;9:466-468. (Abstract) 11.Thatai D, Singh B, Kothari SS, et al: Doppler, pulsus and electrical alternans following prosthetic valve thrombosis. Indian Heart J 1996;48:61-62. (Abstract) 12.Delgado C, Bonnin O, Garriga JM, et al: Intermittent electromechanical dissociation as an unusual sign of prosthetic valve thrombosis in a patient with prosthetic fibrous ingrowth. J Am Soc Echocardiogr 2000;13(7):685– 689. 13.Kapoor A, Sinha N, Srivastava AK: Intermittent prosthetic valve obstruction due to impinging chordal tissue and malrotated disc. Indian Heart J 1997;49:537-539. (Abstract) 14.Masiello P, Mastrogiovanni G, Leone R, et al: One leaflet immobilization after mitral valve replacement with a bileaflet prosthesis. J Heart Valve Dis 1996;5(1):114116.

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EDITOR’S COMMENT

“Mechanical Prosthetic Valve Dysfunction Causing Pulsus Alternans Leading to Intermittent Electromechanical Dissociation: A Case Report And Literature Review” The Editor sadly recalls a personal case of a young mother who had also undergone recent mechanical mitral valve replacement with a single tilting disk prosthesis (Bjork-Shiley) for severe mitral stenosis. She was rushed to hospital by her husband who had noted intermittent fainting spells that were alleviated by a solid whack on the chest. It was assumed by the receiving cardiology service that she suffered intermittent heart block but without ECG confirmation and was booked for a permanent pacemaker implantation. Unfortunately just prior to that procedure she suffered a prolonged episode of hypotension and received external cardiac massage but expired. At autopsy, a single long suture covered with fibrin was wedged in the larger orifice between the disk occluder and the valve housing. Presumably this had floated back and forth during the cardiac cycle with intermittent sticking which was not seen at echocardiography. The presumption of heart block diverted suspicion from the true diagnosis, and external cardiac massage presumably locked the disk occluder tightly on the fibrin-coated single long suture. Thus one other cause of valve sticking and/or obstruction can be added to this review. Bernard S. Goldman