Progression of Coronary Atherosclerosis After Heart Transplantation on Electron-beam Computed Tomography

Rationale and Objectives Cardiac transplant vasculopathy is the most important long-term complication of heart transplantation, with overlapping features with conventional, atherosclerotic coronary artery disease. The aim of this study was to determine the progression of coronary artery disease after heart transplantation by measuring total coronary calcium load. Materials and Methods After heart transplantation, 185 patients were serially examined using electron-beam computed tomography for coronary calcium load for clinical reasons. The mean time between the initial examination and the follow-up scan was 566 days (range, 126–1,436). Coronary calcium load was measured by the Agatston method, and the total calcium scores at both examinations were compared between patients taking and those not taking lipid-lowering medications (statins). Results Patients not taking statins ( n = 94) displayed a median annualized percentage increase in total calcium score of 0 Agatston units, whereas patients taking at least the lowest recommended daily dose of a statin ( n = 84) displayed an annualized percentage decrease of 11 Agatston units. The difference was not statistically significant (Wilcoxon's rank-sum test, P = .35). Only 17 patients had increases of > 24 Agatston units, and eight of them were taking statins (χ 2 test, P = .99). Conclusion The annual rate of progression of coronary calcium load after heart transplantation is low. In this investigation, no beneficial effects of statins could be detected.