Early angiographic results after revascularization by minimally invasive direct coronary artery bypass (MIDCAB)

Objective: Anastomosing the left anterior descending artery (LAD) by use of the internal mammary artery (IMA) via an anterior minithoracotomy represen ts the most commonly performed minimally invasive direct coronary artery by pass (MIDCAB). However, little is known about angiographic results beyond p atency rates. Methods: Therefore, a retrospective analysis of 205 consecuti ve control angiographies was performed evaluating anastomototic patency as well as the angiographic morphology of the left IMA and the LAD. Results: T he overall anastomotic patency rate was 98.0%. As a result of incomplete IM A preparation (6-15 cm) large side branches (n = 4), or an IMA course under tension (n = 6) were occasionally observed. Despite a tension-free course, the IMA appeared fixed to the chest wall without functional compromise in 21 cases. A restrictive thrombus formation occurred once, IMA dissection wa s not seen. Two of the grafts developed spasms. A distal IMA stenosis >50% was seen in five cases. Stenosis of the anastomosis (>50%) itself was found once, as well as unexpected malinsertation to diagonal branches (n = 4). C ompared with preoperative angiograms, de novo stenoses of the LAD were asse ssed proximal (14 less than or equal to 50%, 2 > 50%) and distal (15 less t han or equal to 50%, 2 > 50%) to the anastomosis. Elevation off the LAD out of the vascular bed was an additional finding (n = 12) in a few cases. Con clusions: The overall patency of MIDCAB-LAD-grafting appears to be equivale nt to conventional IMA grafting to the LAD. Particular angiographic finding s, however, may be directly associated to the applied surgical technique. ( C) 1999 Elsevier Science B.V. All rights reserved.