Utility of Early Intravascular Ultrasound after Pediatric Heart Transplantation

Purpose Intravascular ultrasound (IVUS) has been used in adult heart transplant (HTX) recipients early after transplant to assess risk for long-term outcomes, along with differences in therapeutic targets for the treatment of cardiac allograft vasculopathy (CAV). Little is known about the utility of IVUS early after pediatric HTX. We evaluated the use of IVUS early ( Methods All pediatric HTX recipients at our hospital who underwent coronary evaluation via IVUS within 5 years after transplant were included. Maximal intimal thickness (MIT) and associated Stanford IVUS class (SIC) were analyzed and subjects were stratified into two groups [SIC 1-2 (trivial/mild) vs. 3-4(moderate/severe)]. Chi-square, t-test, and Kaplan Meier analyses were undertaken to evaluate association of SIC with long-term outcomes [CAV (diagnosed by angiography or pathology), graft loss from all causes, graft loss from CAV, and death]. Results Seventy-one subjects had IVUS performed within 5 years after HTX. Fifty-four (76%) were SIC 1-2, while 17 (24%) were SIC 3-4. Median time from transplant at IVUS was 3.8 & 3.5 years, respectively (p=0.59). Median age at transplant was 6.4 & 8.7 years, respectively (p=0.80). MIT was 0.17±0.06 & 0.53±0.23 mm, respectively (p Conclusion Early changes in IVUS (