Use of Cardiac CT in the Routine Assessment of Cardiac Allograft Vasculopathy in Heart Transplant Patients: Results from the First 100 Consecutive Patients

PURPOSE: Cardiac allograft vasculopathy (CAV) is an accelerated form of coronary artery disease that affects heart transplant patients (HTx). Routine screening for CAV is warranted. We evaluated the feasibility and utility of cardiac CT to screen for CAV in 100 consecutive HTx patients at our center. METHODS: From Feb 2018 to Jan 2019 all consecutive HTxs who were more than five-years post-transplant were converted from using stress myocardial perfusion imaging to cardiac CT for the annual assessment of CAV. CAV was scored (0 (absent), 1 (mild), 2 (moderate), 3 (severe)) based on coronary CT angiography (CCTA) findings and compared with the most recently known CAV score before CCTA. RESULTS: CCTA was performed in 99 out of 100 patients who were planned for cardiac CT (56 (42-63) years, 65% men, and 11 (8-16) years post-transplant), 1 patient underwent only a calcium scan due to IV access problems. The median Agatston calcium score was 6 (0-85), and 38 patients had no detectable calcium. CCTA showed new obstructive coronary disease (>50% stenosis) in 20 patients. The CAV score was reclassified based on CCTA findings in 37 patients (p<0.001) (Figure 1). There were 53 CAV0, 22 CAV1, 11 CAV2 and 14 CAV3 patients. Mean heart rate during scanning was 75±11 beats per minute and beta-blockers were required in 63 patients. Median radiation dose was 2.5 (1.9-3.5) mSv. Two cases are presented in Figure 2. CONCLUSION: Cardiac CT can be successfully performed in HTxs with a low radiation dose. CCTA detects patients with significant coronary disease which leads to substantial reclassification of CAV grades.