Internal Mammary Artery Grafts Without Optical Assistance

Abstract

Internal mammary artery (IMA) grafts were performed without optical assistance in 175 consecutive patients during a 17-month period. The predominant indications were angina pectoris and the angiographic evidence of a 70% or greater obstruction in one or more major coronary arteries. Eight patients were considered to be in New York Heart Association functional class I, 63 class II, 71 class III, and 33 class IV before the operation. Forty per cent had three major vessels obstructed, and 33% had double vessel disease. IMA grafts were constructed to the anterior descending artery in 151 patients, diagonal branch in 22, and circumflex in two. Two of the 175 and three additional patients had free IMA grafts in the aortocoronary position. Saphenous vein grafts were combined with IMA grafts in 61%. One hospital death occurred, a 0.6% operative mortality. Late clinical results were analyzed in the first 100 patients. Eighty-four of 99 have had complete remission of angina, and 12 are improved. Repeat arteriograms in 65 patients show 65 of 67 IMA grafts open (97%) and 56 (85%) of 66 saphenous vein grafts patent after an average interval of four months. These early clinical and angiographic results are encouraging and indicate that the higher IMA patency may result from less size discrepancy between the graft and the coronary artery. The addition of the technically more complicated IMA graft to direct revascularization does not increase morbidity or mortality.