Abstract 1918: Prevalence of Myocardial Infarction After Heart Transplantation Detected by Contrast Enhanced MRI
Background: Transplant coronary artery disease (TCAD) limits long-term survival after heart transplantation (HTX). X-ray angiography tends to underestimate the degree of TCAD and often underdiagnoses occluded small coronary arteries leading to myocardial infarctions (MI). Contrast Enhanced MRI (CEMRI) is a sensitive non-invasive imaging technique to detect MI. We hypothesized that CEMRI would detect chronic TCAD-related MI even in patients with Xray classified mild TCAD.
Methods: CEMRI (Gadolinium:0.2mmol/kg bw) was performed in 41 HTX patients on a 1.5T Whole Body MRI scanner (Philips Medical Systems). On a workstation images were analysed blindly by two experienced observers. Areas of MI were classified as I = ≤ 50%, II = 50–75%, III = 75–100%. Selective coronary angiography was conducted by using standard Judkins technique. Results were reviewed qualitatively using the TCAD score (TCAD1 = no TCAD;2 = wall irregularities;3 = 50%stenosis;4 ≥ 50%stenosis). Groups were compared using ANOVA. P-values ≤ 0.05 were considered statitistically significant.
Results: TVP1– 4 donor age (34.6/37.6/39.7/39.3ys.) and time after HTX (5.7/6.5/8.8/11.6ys.) were not significantly different. MI was prevalent in all four TCAD grades in cumulative percentage (I = 20%;II = 27%;III = 50%;IV = 100%,see table⇓).
Conclusions: CEMRI is a novel and sensitive imaging technique to detect MI in TCAD. Unexpectedly, even in angiographically classified low grades of TCAD there is a prevalence of transmural MI which could have potential impact for future treatment and modified risk stratification for HTX patients.