Detection of transplant coronary artery disease using multidetector computed tomography with adaptative multisegment reconstruction.

OBJECTIVES: This study sought to determine whether multidetector computed tomography (MDCT) may be able to detect occlusive coronary disease in transplanted hearts.
BACKGROUND: In heart transplant recipients, asymptomatic coronary disease requiring frequent surveillance commonly develops. Recent advancements in MDCT allow for noninvasive assessment of the coronary vessels.
METHODS: Electrocardiogram-gated contrast-enhanced MDCT scans (16 x 0.75-mm detectors, 420 ms rotation, 100 ml contrast) with multisegment reconstruction were performed on 54 transplant recipients within 6 +/- 11 days of quantitative coronary angiography (QCA). Heart rate at the time of the scan was 90 +/- 11 beats/min. Coronary arterial segments >1.5 mm in diameter were analyzed by independent investigators.
RESULTS: There was a good correlation between MDCT and QCA percent stenosis (r = 0.75, p < 0.01, SEE = 15%). Of the 791 segments identified by QCA, 754 (95%) were analyzable by MDCT. The sensitivity, specificity, and positive and negative predictive values of MDCT compared with QCA for the detection of segments with significant (>50%) stenosis were 86%, 99%, 81%, and 99%, respectively. The MDCT correctly identified 15 of the 16 (94%) transplant patients classified by QCA as having occlusive coronary artery disease and 29 of the 37 patients without significant stenosis (78%). In 1 patient who received intravenous beta-blockers, transient bradycardia requiring temporary pacing developed, but there were no other complications.
CONCLUSIONS: Detection of occlusive coronary disease in heart transplant recipients with elevated resting heart rate by MDCT is feasible using multicycle reconstruction. The need for surveillance invasive coronary angiography in transplant recipients might be mitigated by use of MDCT.