Vascular Surgery Microvascular Vasodilatory Function at Three Months and One Year After Cardiac Transplantation

Coronary occlusive disease (COD) is the major complication after the first year in cardiac transplant patients and may be initiated by perioperative factors. Coronary angiography is usually used but is an insensitive monitoring method. Coronary flow measurements allow investigation of the responses of the coronary microvasculature. The authors inves-tigated the hypothesis that coronary flow responses (CFR) to papaverine (a nonen-dothelial-dependent vasodilator) and acetylcholine (an endothelial dependent vasodilator) are impaired early after cardiac transplantation. Ten patients were studied at three months (3/12) and one year (12/12) after transplantation. No patients had COD on angiography A Doppler flow probe was inserted into the proximal left anterior descending coronary artery in all patients. Incremental doses of intracoronary papaverine (Pap), and glyceryl trinitrate followed by acetylcholine (Ach), were given until maximum hyperemia was achieved. CFR for each drug was defined as the ratio of resting to peak coronary blood velocity. CFRPap was lower at 3/12 as compared with 12/12: 3.1 SD 1.1 versus 3.9 SD 1.3 (P = 0.05, Student’s t test). CFRAch was impaired at 3/12 as compared with 12/12: 1.9 SD 0.6 versus 2.6 SD 0.5 (P = 0.01). Endothelial- and nonendothelial-dependent microvascular vasodilation are impaired early after cardiac transplantation but subsequently improve. Perioperative coronary damage may play a crucial role in the pathogenesis of COD. at PENNSYLVANIA STATE UNIV on May 9, 2016ves.sagepub.comDownloaded from 10