Iatrogenic circumflex coronary lesion in mitral valve surgery: case report and review of the literature.

Ischemic iatrogenic lesions can complicate surgical procedures on the mitral valve. One of the causative mechanisms is direct injury to or distortion of the circumflex coronary artery. The risk of damaging the circumflex coronary artery depends mainly upon the proximity of that vessel to the posterior segment of the mitral annulus, and this varies from patient to patient. Herein, we report a case of iatrogenic circumflex coronary artery lesion after mitral annuloplasty, and we review the literature on the subject, in order to highlight a possible relationship between iatrogenic circumflex lesions and coronary dominance. In a 60-year-old man who had severe mitral regurgitation due to prolapse of both leaflets, preoperative coronary angiography showed irregularities only along the left anterior descending coronary artery and a coronary network of right dominance. The patient underwent mitral annuloplasty (32-mm Carpentier-Edwards ring) by means of minimally invasive right thoracotomy through the right 4th intercostal space (HeartPort). When the procedure was over, and before the patient was taken to intensive care, ventricular fibrillation developed; the administration of direct-current shock (200 joules) resulted in a resumption of sinus rhythm. Repeat transesophageal echocardiography showed posterolateral dyskinesis of the left ventricle and ST-segment elevation suggestive of acute lateral myocardial infarction. Emergency cardiac catheterization revealed a subocclusion of the distal circumflex coronary artery. Dual percutaneous angioplasty and stenting (Taxus, 2.5 x 24 mm) was performed with optimal result. At the 1-year follow-up, the patient showed good results of the mitral annuloplasty.