Minimally Invasive Direct Coronary Artery Bypass Grafting: Two-Year Clinical Experience

Abstract

Background. Interest in minimally invasive coronary artery bypass grafting has been increasing. Methods. From April 1994 through December 1996, 199 patients (age, 36 to 93 years) underwent minimally invasive coronary artery bypass grafting through minithoracotomy, subxiphoid, and lateral thoracotomy incisions, with internal mammary artery, gastroepiploic artery, and composite grafts placed using local coronary artery occlusion. Results. The conversion rate to sternotomy was 7% (14/199). Preoperative risk factors included unstable angina (n = 83), reoperative coronary artery bypass grafting (n = 54), low ejection fraction (n = 53), congestive heart failure (n = 44), renal insufficiency (n = 25), chronic obstructive pulmonary disease (n = 36), cerebrovascular accident (n = 22), and diffuse vascular disease (n = 47). Morbidity included wound infections (n = 5), reoperation for management of bleeding (n = 6) and acute graft occlusion (n = 2), perioperative stroke (n = 1), atrial fibrillation (n = 14), and perioperative myocardial infarction (n = 7). The operative mortality was 3.8% (7/185). The number of grafts placed in 185 patients was as follows: single, 156; double, 28; and triple, 1. Early (less than 36 hours) angiography and Doppler flow assessment of the coronary anastomoses in 85% of the patients showed that 92% were patent. Routine use of mechanical stabilization of the coronary artery since April 1996 was found to be associated with an increase in the patency rate of the left internal mammary artery–left anterior descending coronary artery anastomosis to 97%, versus 89% ( p = 0.055) associated with conventional immobilization techniques. Of the 148 patients followed up beyond 1 month (range, 1 to 32 months; mean, 9.2 ± 7.4 months) postoperatively, 3 have died (3 to 7 months), and of the 145 survivors the cardiac-related event (percutaneous transluminal coronary angioplasty, reoperation, readmission for recurrent angina, and congestive heart failure)–free interval was 93%. Conclusions. The minimally invasive coronary artery bypass grafting operation is safe and effective. Regional cardiac wall mechanical immobilization enhances the early graft patency and must be considered an essential part of this operation.