Intravascular ultrasound guided selection for early non-invasive cardiac allograft vasculopathy screening in heart transplant recipients.

BACKGROUND Non-invasive screening for cardiac allograft vasculopathy (CAV) instead of invasive coronary angiography (ICA) within the first 3 to 5 years after heart transplantation (HTx) is controversial. We evaluated a strategy of intravascular ultrasound (IVUS)-guided conversion to early non-invasive screening post-HTx. METHODS A single-center study of 103 consecutive HTx recipients from 2008-2018 undergoing ICA at 1 year post-HTx. Of 88 patients with normal 1-year ICA, sixty-six patients underwent IVUS examination for risk stratification by maximal intimal thickness (MIT) into: (i) low-risk group (MIT<0.5 mm) (n=41, 62%) followed non-invasively versus (ii) high-risk group (MIT≥0.5 mm) (n=25, 38%) followed with yearly ICA. Both groups underwent ICA at year 5 post-HTx. We evaluated a combined endpoint of angiographic CAV and death at 5-year follow-up post-HTx. RESULTS Median (IQR) age was 51 (33-60) years and 62% were male. Follow-up was 1443 (1125-1456) days. Survival free from angiographic CAV (Kaplan-Meier) differed significantly between groups (log-rank p<.0001). A subgroup of 27 patients completed ICA at year 5 and proportion of angiographic CAV was significantly lower in low-risk patients (p<.0001). CONCLUSION IVUS-guided selection for early non-invasive CAV screening appears to be safe and holds promise as a novel strategy for early risk stratification and CAV surveillance post-HTx.