Posttransplant obesity and hyperlipidemia: Major predictors of severity of coronary arteriopathy in failed human heart allografts

The contribution of specific risk factors to the development of coronary arteriopathy in human heart allografts remains unclear. Allografts from 15 patients, 11 male and 4 female, aged 15 to 58 years (mean, 40 years), with patient survival from 0.5 to 24 months (mean, 8.6 months) with ''triple drug therapy,'' had the entire coronary artery trees removed, with 184 4-mm arterial segments studied. Luminal narrowing was measured by means of digitization on a video image analysis system, and extent of luminal narrowing (cross-sectional area reduction: [Intimal area/Intimal area + Luminal area] x 100 = %) was related to 40 individual risk factors, including demographic, hemodynamic, immune, environmental, and therapeutic factors. Mean luminal narrowing, considering all coronary segments, was significantly greater in patients with higher versus lower mean cholesterol levels (246 vs 163 mg/dl), triglyceride levels (328 vs 145 mg/dl), and body mass indices (31 vs 22 kg/m²) at 62% versus 38%, 59% versus 42% and 61% versus 44% luminal narrowing, respectively. Considering all coronary segments from all heart allografts, mean luminal narrowing steadily progressed with duration of implant, reaching >60% within 6 months. Mean luminal narrowing was identical in proximal and distal halves of coronary trees at 51% and 50%, respectively. Rejection episodes, considering all degrees of rejection, were strongly related to percent luminal narrowing (p = 0.01). Multivariate analysis indicated the single most predictive risk factor to be posttransplant body mass index (r = 0.77; p = 0.0009). Thus coronary risk factors play a significant role in the evolution of coronary arteriopathy in human heart allografts. Strategies to reduce blood lipids and obesity appear worthwhile for the further improvement of graft and patient survival.