Letters to the Editor / European Journal of Cardio-thoracic Surgery 23 (2003) 136–140
Letter to the Editor Iatrogenic left main and proximal right coronary artery stenoses after aortic valve replacement
Roland G. Demaria, Olivier Chavanon, Louis P. Perrault* Department of Surgery and Research Center, Montreal Heart Institute, Montreal, Que´ bec H1T 1C8, Canada Received 17 September 2002; accepted 17 October 2002 Keywords: Iatrogenic left main coronary artery stenosis; Aortic valve replacement; Coronary artery bypass grafting
We read with great interest the case report by Yavuz et al. [1] about a severe iatrogenic stenosis of the left main coronary artery (LMCA) and proximal right coronary artery (RCA) after direct instillation of cardioplegia into the coronary ostia during an aortic and mitral valve replacements, 4 months earlier. We agree that this complication may be grossly underreported and may account for sudden death or adverse outcome after aortic valve replacement (AVR). In a recently published retrospective study, dating from 1987 to present [2], seven cases of iatrogenic left main coronary stenosis were observed at the Montreal Heart Institute, after 2158 AVR, representing 0.3% of all the cases. The interval between AVR and symptoms ranged from 4 to 11 months (mean: 7.3). The symptoms were usually severe unstable angina (5/7). The LMCA was involved in all cases with the stenosis ranged from 55 to 75% and one occlusion and, the RCA in only two cases. Intermittent antegrade cardioplegia had been used in three cases and continuous in four. The specific type of antegrade cannulation for cardioplegia, intermittent or continuous, may have some importance, because no catheters have the potential of producing the same trauma on the arterial wall. Our surgical research group has focused for a number of years on the investigation of endothelial function as a marker of surgical intimal injury, especially for assessment of intracoronary devices such intracoronary shunts or cannulas to deliver cardioplegia or obtain hemostasis during off-pump coronary surgery, all of which can lead to endothelial dysfunction and chronic intimal hyperplasia [3]. In an experimental study, shunts were shown to create a severe endothelial dysfunction [4], due to the rubbing. However, the hydrodynamic pressure of the cardioplegia instilled may also play an additional role in creating injury. Various systems have been developed such as simple intra coronary cannulas for intermittent cardioplegia, stiff or soft, which may create intimal lesions by rubbing, and cannulas with occlusive balloons for continuous cardioplegia to avoid repositioning and withdrawal which exert a constant transmural pressure on the arterial wall, creating trauma which may be deleterious over the period of time
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necessary for an AVR. The safest technique for morphological and functional preservation of the coronary artery endothelial and muscular layers remains to be established, but the smallest soft catheters inserted gently with intermittent administration of cardioplegia at low pressure (,100 mmHg) should be the preferred choice, if antegrade cardioplegia is necessary. Direct cannulation of the coronary ostia remain very frequently used by surgeons during AVR and ascending aortic procedures. However, because of the risks described above, use of intracoronary cannulas to deliver cardioplegia must always be guided by the concern of inducing as little trauma as possible. Considering the pitfalls and dismal results of myocardial revascularization for iatrogenic LMCA stenosis after AVR [2], emphasis on prevention of this complication with systematic use of the retrograde route and judicious selective application of antegrade catheters remains of paramount importance.
References [1] Yavuz S, Go¨ ncu¨ MT, Sezen M, Tu¨ rk T. Iatrogenic left main and proximal right coronary artery stenoses after aortic valve replacement. Eur J Cardiothorac Surg 2002;22:472–475. [2] Chavanon O, Carrier M, Cartier R, He´ bert Y, Pellerin M, Perrault LP. Early reoperation for iatrogenic left main stenosis after aortic valve replacement: a perilous situation. Cardiovasc Surg 2002;10:256–263. [3] Perrault LP, Menasche´ P, Wassef M, Bidouard JP, Janiak P, Villeneuve N, Jacquemin C, Bloch G, Vilaine JP, Vanhoutte PM. Endothelial effects of hemostatic devices for continuous cardioplegia or minimally invasive operations. Ann Thorac Surg 1996;62:1158–1163. [4] Chavanon O, Perrault LP, Menasche´ P, Carrier M, Vanhoutte PM. Endothelial effects of hemostatic devices for continuous cardioplegia or minimally invasive operations. Updated in 1999. Ann Thorac Surg 1999;68:1118–1120.
* Corresponding author. Tel.: 11-514-376-3330 ext. 3715; fax: 11-514376-1355. E-mail address:
[email protected] (L.P. Perrault). PII: S1010 -7 940(02)00680 -2
Reply to the Letter to the Editor Reply to Demaria et al.
Senol Yavuz*, M. Tugrul Go¨ ncu¨ , Tamer Tu¨ rk Department of Cardiovascular Surgery, Bursa Yu¨ ksek Ihtisas Teaching and Research Hospital, Duacinari, 16330 Bursa, Turkey Received 1 October 2002; accepted 17 October 2002 Keywords: Iatrogenic left main coronary artery stenosis; Aortic valve replacement; Coronary artery bypass grafting
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Letters to the Editor / European Journal of Cardio-thoracic Surgery 23 (2003) 136–140
We thank Dr Demaria et al. for their valuable comments and interest in our recent publication [1], and we are honored by the attention paid to our work. We have read their article recently published in Cardiovascular Surgery [2]. In their retrospective study, they have also observed the findings similar to our case. Dr Demaria et al. offer an additional useful tip for the etiology of endothelial dysfunction [3]. We agree that the safest technique for morphological and functional preservation of the coronary artery endothelial and muscular layers remains to be established. Iatrogenic stenosis of the left main coronary artery is a disastrous complication after aortic valve replacement (AVR). The true incidence of this complication is not known. However, there must be more cases that have not been reported, and the natural history of this condition leads to inevitable death. As we state in our article, the etiology of these lesions remains unproven, but most likely they represent mechanical injury to the vessel wall because of cannulation of the coronary ostia or because of the pulsatile pressure of the perfusing balloon cannula, and fibrous proliferation in the aortic root secondary to turbulent flow around a prosthetic valve. At an autopsy study, Trimble et al. [4] reported that histologically, at the ostia and in the areas of coronary arterial stenosis, the intima was markedly thickened by loose cellular fibromuscular connective tissue and morphologically, the intimal thickening was distinctly different from that caused by atherosclerosis. We appreciate the opportunity to compare our agreements with Dr Demaria et al. As they describe in their letter and we state in our article, various measures to prevent the development of iatrogenic left main coronary artery stenosis
during coronary arterial perfusion include using retrograde delivery as an alternative method of myocardial protection, avoiding placement of sutures around coronary ostia to secure perfusion cannula, avoidance of high pressure flow, maintenance of coronary perfusion under 100 mmHg, and no using a too-large coronary perfusion cannula. Whatever the etiology is, coronary ostial stenosis must be suspected in patients who develop recent onset of severe angina, ventricular arrhythmias or congestive heart failure after AVR. Surgical intervention (coronary artery bypass grafting or surgical angioplasty) should be performed without delay.
References [1] Yavuz S, Go¨ ncu¨ MT, Sezen M, Tu¨ rk T. Iatrogenic left main and proximal right coronary artery stenoses after aortic valve replacement. Eur J Cardiothorac Surg 2002;22:472–475. [2] Chavanon O, Carrier M, Cartier R, He´ bert Y, Pellerin M, Perrault LP. Early reoperation for iatrogenic left main stenosis after aortic valve replacement: a perilous situation. Cardiovasc Surg 2002;10:256–263. [3] Perrault LP, Menasche´ P, Wassef M, Bidouard JP, Janiak P, Villeneuve N, Jacquemin C, Bloch G, Vilaine JP, Vanhoutte PM. Endothelial effects of hemostatic devices for continuous cardioplegia or minimally invasive operations. Ann Thorac Surg 1996;62:1158–1163. [4] Trimble AS, Bigelow WG, Wigle ED, Silver MD. Coronary ostial stenosis: a late complication of coronary perfusion in open-heart surgery. J Thorac Cardiovasc Surg 1969;57:792–795. * Corresponding author. Tel.: 190-224-360-5050; fax: 190-224-3605055. E-mail address:
[email protected] (S. Yavuz).
PII: S1 010-7940(02 )00 681-4
