ANGIOGRAPHIC, INTRAVASCULAR ULTRASOUND AND FUNCTIONAL FINDINGS EARLY AFTER ORTHOTOPIC HEART-TRANSPLANTATION

Accelerated graft atherosclerosis is responsible for increased mortali ty and morbidity among heart transplant recipients. The aim of this in -vivo study was to evaluate coronary atherosclerotic vessel alteration s and endothelial function. Seventeen patients (14 males; mean age 49. 3 years; range 24 to 69) were studied an average of Il weeks (range 5 to 21) after heart transplantion because of coronary artery disease (n = 8), dilative cardiomyopathy (n = 7), mitral valve replacement (n = 1) and left atrial metastases of a leiomyosarcoma (n = 1). Mean age of the donor hearts (9 males) was 29 years (range 12 to 55). All recipie nts underwent biplane ventriculography and coronary angiography, In th is study population, a total of 120 coronary segments (main stem, 21; left anterior descending artery, 85; circumflex artery, 14) were analy zed by intravascular ultrasound (20 MHz, 3.5F). In 13 patients, acetyl choline was infused into the proximal left anterior descending artery (10(-8) to 10(-5) M) to evaluate vasomotion within this segment. Regio nal contraction abnormalities were documented in 2 patients, Nine segm ents angiographically showed non-critical stenoses (5 patients). Intra vascular ultrasound detected 52 cross-sectional areas with a three-lay er pattern indicating intimal thickening, Mean circumferential extensi on of intimal proliferation was 192 degrees, mean intimal thickness 0. 35 mm. Only 5 segments of the sonographically pathological cross-secti onal areas showed angiographical evidence of atherosclerotic lesions. Intracoronary administration of acetylcholine at doses of 10(-8) and 1 0(-7) M resulted in vasoconstriction of the examined coronary segment in only 2 patients; the intracoronary application of acetylcholine at doses of 10(-6) and 10(-5) M revealed coronary vasoconstriction in 10 of the total of 13 patients. Using intravascular ultrasound, coronary artery lesions in heart transplant recipients can already be depicted at a very early stage. The abnormal response to acetylcholine in most of the heart recipients is independent of the extent of atheroscleroti c vessel abnormalities documented by ultrasound or angiography