Aortic Valve Endocarditis by Capnocytophaga Haemolytica

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CASE REPORT GUTIERREZ-MARTIN ET AL AORTIC VALVE ENDOCARDITIS BY CAPNOCYTOPHAGA HAEMOLYTICA

Ann Thorac Surg 2007;84:1008 –10

Fig 2. Computed tomographic scan of the midstent level (left) and the distal extent of the stent (right).

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incorporate T11 and T12 intercostal arteries down to the level of the visceral vessels. The stent was not incorporated and was easily removed after the aorta was opened. The patient had postoperative atelectasis and pulmonary edema, but recovered well with appropriate treatment and was discharged home on postoperative day 16. Three months later the patient underwent an echocardiography that showed stable trace aortic regurgitation, and also a computed tomographic scan that showed a normal postrepair thoracoabdominal aorta.

Comment Endovascular technology is gaining a foothold in the field of thoracic aortic aneurysm repair. It offers a muchdesired minimally invasive approach and has produced acceptable midterm results [1, 2]. However, there are unique complications associated with endovascular repair of thoracic aneurysms. Therefore, although many of these complications can be treated through endovascular access, others require an open approach [4, 7]. This case demonstrates that the thoracoabdominal aorta can expand after endovascular therapy and stent seals can fail both proximally and distally. This potential problem underscores the importance of continued careful radiologic surveillance after endovascular stent placement. As published midterm studies of thoracic endovascular stenting mature into long-term studies, it will be interesting to see the rate of reintervention necessitated by time-related morphologic changes in the aorta. This information will become particularly important as the application of this technology widens to include younger and healthier patients with longer life expectancies and fewer risk factors that could compete with the risk of stent failure. From among the many surgical options available, we chose a staged approach, starting with a David procedure to preserve the patient’s aortic valve and then performing open thoracoabdominal aneurysm repair. Another possible option in this type of patient, notwithstanding the technical challenges, is to take an endovascular approach to the thoracoabdominal aneurysm by using custom-made endografts or by stenting in conjunction with de-branching. Continued aneurysmal dilatation after stenting of the thoracic aorta can lead to repair failure and therefore warrants continued surveillance. When this complication occurs, further intervention should be tailored to the anatomical morphology of the aorta and patient-related variables. © 2007 by The Society of Thoracic Surgeons Published by Elsevier Inc

Dr Stephen N. Palmer, PhD, ELS, contributed to the editing of this article.

References 1. Wheatley GH III, Gurbuz AT, Rodriguez-Lopez JA, et al. Midterm outcome in 158 consecutive Gore TAG thoracic endoprostheses: single center experience. Ann Thorac Surg 2006;81:1570 –7. 2. Marcheix B, Dambrin C, Bolduc JP, et al. Midterm results of endovascular treatment of atherosclerotic aneurysms of the descending thoracic aorta. J Thorac Cardiovasc Surg 2006;132: 1030 – 6. 3. Najibi S, Terramani TT, Weiss VJ, et al. Endoluminal versus open treatment of descending thoracic aortic aneurysms. J Vasc Surg 2002;36:732–7. 4. Neragi-Miandoab S, Tuchak J, Bakhos M, Schwartz JP. Open repair of a new aneurysm of the thoracoabdominal aorta after endovascular stent placement. J Thorac Cardiovasc Surg 2006;132:157– 8. 5. van Sambeek MR, Hendriks JM, Tseng L, van Dijk LC, van Urk H. Sac enlargement without endoleak when and how to convert and technical considerations. Semin Vasc Surg. 2004; 17:284 –7. 6. David TE, Feindel CM. An aortic valve-sparing operation for patients with aortic incompetence and aneurysm of the ascending aorta. J Thorac Cardiovasc Surg 1992;103:617–21. 7. Parmer SS, Carpenter JP, Stavropoulos SW, et al. Endoleaks after endovascular repair of thoracic aortic aneurysms. J Vasc Surg 2006;44:447–52.

Aortic Valve Endocarditis by Capnocytophaga Haemolytica Maria A. Gutierrez-Martin, MD, Omar A. Araji, MD, PhD, Jose M. Barquero, MD, Carlos Velázquez, MD, Mariano García-Borbolla, MD, Pastora Gallego, MD, and Carlos A. Infantes, MD, PhD Department of Cardiovascular Surgery, Virgen Macarena University Hospital, Seville, Spain

We report a case of a 51-year-old patient with suspected prosthetic valve endocarditis. Capnocytophaga haemoAccepted for publication March 23, 2007. Address correspondence to Dr Gutierrez-Martin, Virgen Macarena University Hospital, C/Muro de los Navarros 24, Bajo E4, Seville, 41003, Spain; e-mail: [email protected].

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Ann Thorac Surg 2007;84:1008 –10

CASE REPORT GUTIERREZ-MARTIN ET AL AORTIC VALVE ENDOCARDITIS BY CAPNOCYTOPHAGA HAEMOLYTICA

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lytica was isolated in blood cultures and the repeated echocardiograms showed growth of vegetations and disruption of the proximal prosthetic valve suture line with progressive aortic regurgitation. The patient underwent a root debridement and replacement with a stentless bioprosthesis. (Ann Thorac Surg 2007;84:1008 –10) © 2007 by The Society of Thoracic Surgeons

C

We describe the case of a 51-year-old patient who had undergone two previous aortic valve replacements; the first one because of an aortic stenosis in 2003 and the second procedure because of a mismatch in 2006 when we implanted a stentless bioprosthesis (Sorin Freedom, 19 mm [Sorin Medical, Milan, Italy]). Eight months after the last surgery the patient began having a fever, migratory arthritis, and microemboli in the four extremities. According to the initial suspicion of a prosthetic valve infective endocarditis, we initiated an empiric antibiotic treatment with ceftriaxone, cloxacillin, and gentamicin. The in-hospital echocardiography revealed a central aortic regurgitation and an anechoic image at the noncoronary and right coronary cusps. Ten days after his admission into the hospital, C haemolytica was isolated in blood cultures, and specific antibiotic treatment with ceftriaxone was begun. The repeated echocardiographic studies revealed the growth of vegetations, the disruption of the proximal suture line of the prosthesis, and progression of the aortic regurgitation (Fig 1). The patient was operated on after 2 weeks with antibiotic treatment, including the first empiric one because of his unfavorable evolution. We found vegetations in the noncoronary cusp, disruption of the proximal suture line at this noncoronary cusp, and an abscess in the right coronary cusp. The patient underwent debridement of the abscess and reimplantation of a stentless bioprosthesis (Sorin Freedom, 19 mm [Sorin Medical]). The postoperative period was characterized by hemodynamic instability, the insertion of an intraaortic balloon pump, and high doses of amines. He died 18 hours after surgery because of an intractable ventricular fibrillation. The results of intraoperative blood cultures were negative. No autopsy was performed.

Fig 1. Last echocardiographic study before surgery: disruption of the proximal suture line, an anechoic image in noncoronary and right coronary cusps that could be a pseudoaneurysm and an image of a vegetation in the right coronary cusp.

Comment Capnocytophaga spp are fastidious, slow growing, gramnegative rods that inhabit the oral cavity. This microorganism grows best in an anaerobic or microaerophilic environment with increased concentration of carbon dioxide [1]. Thus it was given its name from the Greek word capnos (smoke) meaning like carbon dioxide. There are many Capnocytophaga species, five of them have been recovered from the human oral cavity (ie, C gingivalis, C ochracea, C sputigena, C granulosa, and C haemolytica; the last two species listed are the most recent Capnocytophaga ones isolated from supragingival dental plaque of adults; the first report recounts the presence of these two species dated from 1994 [2]. Apart from this group of microorganisms, which are common inhabitants of the human being, there is another significant Capnocytophaga species named C canimorsus, which is known as dysgenic fermenter 2 that forms part of the normal oral flora of dogs and cats. This group of organisms are considered among the Hemophilus spp, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella spp (HACEK) group of fastidious, gram-negative organisms that are capable of causing endocarditis and are characterized for slow growth in blood cultures. Invasive Capnocytophaga infections have been reported in immunocompromised patients and in the normal host after animal bites. Neutropenia and oral mucositis are the most important risk factors predisposing to bloodstream infection with the genus [3]. Patients with other conditions associated with immunosuppression, such as short bowel syndrome and end-stage liver disease, also seem to be prone to Capnocytophaga infection. More recently, Capnocytophaga infections in immunocompetent patients have been reported. Capnocytophaga spp septicemia has rarely been complicated by serious deepseated infections, such as meningitis, endocarditis, ar-

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apnocytophaga haemolytica is a gram-negative bacterium present in the oral cavity that has been related exclusively to periodontal disease. Other Capnocytophaga species are protagonists of described serious diseases in the literature, such as sudden sepsis, meningitis, or endocarditis (ie, C canimorsus [transmitted by dog bites]) and some present species in the human oral cavity (ie, C ochracea, C sputigena, or C gingivalis), which act like opportunistic pathogens in immunosuppressed patients. In this article we believe that we describe the first known case of endocarditis produced by C haemolytica.

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thritis, pleuritis, endophthalmitis [4], pneumonia [5], and osteomyelitis. Concretely, C gingivalis, C ochracea, and C sputigena have been implicated as focal infection agents in systemic disease, especially in immunocompromised patients with autologous stem cell transplantation or patients with neutropenia because of myelodysplastic syndromes, aplastic anemia, lymphomas, and acute leukemias [6]. There is a case report of the isolation of C granulosa from an abscess in the lumbosacral area [7], and C canimorsus has been associated with a variety of conditions including meningitis, fulminant septicemia, cellulites, and endocarditis. However, we believe there has not been any previous report of a systemic infection due to C haemolytica to date. Most reported cases of Capnocytophaga spp infections have been susceptible to antibiotics including cephalosporin, ureidopenicillin, and fluoroquinolone; however, there are case reports of isolates resistance to quinolones or beta-lactams [8]. This occasional existence of resistant strains makes susceptibility testing useful for administration of the proper antibiotic therapy. We believe that this is the first reported case of endocarditis related to C haemolytica. After the correct diagnosis of this disease, we tried a treatment with intravenous ceftriaxone (2 g) every 24 hours. Although many of the cases reported in the literature were susceptible and responded to the antibiotic therapy, in our case the patient needed a surgical excision of the infected material and a new aortic prosthesis.

References 1. Fung JC, Berman M, Fiorentino T. Capnocytophaga: a review of the literature. Am J Med Technol 1983;49:589 –91. 2. Yamamoto T, Kajiura S, Hirai Y, Watanabe T. Capnocytophaga haemolytica sp. nov. and Capnocytophaga granulosa sp. nov., from human dental plaque. Int J Syst Bacteriol 1994;44:324 –9. 3. Bonatti H, Rossboth DW, Nachbaur D, Fille M, et al. A series of infections due to Capnocytophaga spp in inmunosuppressed and inmunocompetent patients. Clin Microbiol Infect 2003;9:380 –7. 4. Phipps SE, Tamblyn DM, Badenoch PR. Capnocytophaga canimorsus endophtalmitis following cataract surgery. Clin Experiment Ophthalmol 2002;30:375–7. 5. Geisler WM, Malhotra U, Stamm WE. Pneumonia and sepsis due to fluoroquinolone-resistant Capnocytophaga gingivalis after autologous stem cell transplantation. Bone Marrow Transplant 2001;28:1171–3. 6. Ciantar M, Spratt DA, Newman HN, Wilson M. Capnocytophaga granulosa and Capnocytophaga haemolytica: novel species in subgingival plaque. J Clin Periodontol 2001;28: 701–5. 7. Ebinger M, Nichterlein T, Schumacher UK, Mannake B, Schmidt D, Bohn I. Isolation of Capnocytophaga granulosa from an abscess in an inmunocompetent patient. Clin Infect Dis 2000;30:606 –7. 8. Mantadakis E, Danilatou V, Christidou A, Stiakaki E, Kalmanti M. Capnocytophaga gingivalis bacteremia detected only on quantitative blood cultures in a child with leukemia. Pediatr Infect Dis J 2003;22:202– 4. © 2007 by The Society of Thoracic Surgeons Published by Elsevier Inc

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Aortic Elongation Induced Aortic Stenosis (AEAS) Amit K. Shah, MA, MB/BChir, Roger M. O. Hall, MBChB, FANZCA, and Stephen R. Large, MS, FRCS Papworth Hospital NHS Foundation Trust, Papworth Everard, Cambridge, United Kingdom

We present a case of a 71-year-old man who presented with aortic stenosis. This was pseudo-aortic obstruction resulting from the mitral valve subvalvular apparatus impacting into a normal aortic valve as a result of elongation of the ascending aorta. To place this case in context, we also provide a review of left ventricular outflow obstruction with an emphasis on subvalvular stenosis. (Ann Thorac Surg 2007;84:1010 –2) © 2007 by The Society of Thoracic Surgeons

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eft ventricular outflow tract obstruction (LVOTO) is an extensively studied phenomenon with numerous causes. The principal aim of therapy is to provide unobstructed egress of blood from the left ventricle at a timely interval in the evolution of the underlying problem to minimize secondary complications such as acquired ventricular hypertrophy. Reports on observed and previously undescribed pathophysiology will continue to educate us and improve our understanding of both congenital and acquired LVOTO. The patient was previously fit and well. An ejection systolic murmur found during a routine medical examination was associated with significant dilatation (6 cm in diameter) and elongation of the ascending aorta. In addition there was moderate aortic stenosis on transthoracic echocardiography. The aortic peak gradient was 88 mm Hg and the valve area was 0.8 cm2. The left ventricle showed good systolic function and moderate hypertrophy without dilatation. No obvious dissection was observed. His past medical history included essential hypertension and an isolated episode of temporal arteritis. An on-table transesophageal echocardiogram revealed a normal aortic valve with no transvalvular gradient (Figs 1A, 1B, 2). Direct examination of the aortic valve at operation confirmed it to be tricuspid with normal leaflets. Calcification on the anterior leaflet of the mitral valve was seen through the left ventricular outflow tract with appearances suggestive of systolic anterior motion. The aorta was dilated and elongated, and the operative procedure involved the removal of the calcific plaques from the anterior mitral leaflet and resection of 7 cm of ascending aorta drawing the aortic valve away from the mitral subvalvular apparatus. The patient had a normal native aortic and mitral valve seen on postoperative transesophageal echocardiography. He went on to have an uneventful recovery. HisAccepted for publication March 23, 2007. Address correspondence to Dr Large, Papworth Hospital NHS Foundation Trust, Papworth Everard, Cambridge, CB23 3RE, United Kingdom; e-mail: [email protected].

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