A comparison of intravascular ultrasound with coronary angiography for evaluation of transplant coronary disease in pediatric heart transplant recipients

Background: The purpose of this study was to assess the sensitivity of coronary angiography versus intravascular ultrasound for detecting significant transplant coronary artery disease in children. We also examined associations between potential risk factors for transplant coronary artery disease and intravascular ultrasound findings, and evaluated the safety of intravascular ultrasound. Methods: All pediatric heart transplant patients who had intravascular ultrasound following routine coronary angiography were included. Transplant coronary artery disease was quantified by assigning Stanford classes and calculating intimal indices for intravascular ultrasound images. These findings were compared with qualitative coronary angiography findings. Risk factors for transplant coronary artery disease, cardiac events and complications were recorded. Results: Sixteen patients had 27 intravascular ultrasound procedures during the study period. All patients had evidence of transplant coronary artery disease at their latest intravascular ultrasound study. Of the patients whose most severely afflicted coronary artery underwent both imaging modalities at the latest study, 50% had significant transplant coronary artery disease (Stanford Class ≥II) by intravascular ultrasound and normal coronary angiography. A higher mean first-year biopsy score may be associated with significant transplant coronary artery disease by intravascular ultrasound, but a large number of patients will be required to determine this with statistical certainty. One major complication occurred early in the experience. Conclusions: In children, intravascular ultrasound is more sensitive for detecting significant transplant coronary artery disease than coronary angiography, but may add cost, time and potential morbidity to screening protocols. Prospective, multicenter studies are needed to best utilize intravascular ultrasound in this patient population.