[Variability of transplant vasculopathy. A study with intravascular ultrasound].

Cardiac allograft vasculopathy (CAV) influences long-term survival of patients after heart transplantation. Histopathology studies have demonstrated the insensitivity of coronary angiography (CA) for detecting CAV. Intravascular ultrasound (IVUS) is an imaging technique that provides qualitative and quantitative characterization of vessel wall morphology. The purpose of this study was to compare in vivo IVUS with coronary angiography in cardiac transplant recipients and to analyze intraindividual and segmental variability of CAV involvement. IVUS studies were performed at routine follow-up angiography in 33 patients 48 +/- 23 months after heart transplantation. 134 segments (1 to 8 per patient) were classified by IVUS according to a modified Stanford score (morphometric grading from 1 to 6). Patient characteristics and laboratory findings were further compared with intimal thickening. 114/134 (85%) segments were normal with CA. In 56% of these segments, IVUS revealed mild to moderate (IVUS grade 2 to 4, n = 45) or severe (IVUS grade 5 to 6, n = 19) intimal thickening. Mean IVUS scores between proximal and distal segments were not different (2.9 +/- 1.9 vs. 2.4 +/- 1.9, ns). Intimal thickening was more pronounced in segments of the LAD compared to the RCX (3.1 +/- 2.0 vs. 2.03 +/- 1.6, p < 0.01). In 39% of patients, the intraindividual extent of CAV was very heterogeneous (range: 3 to 5 IVUS grades). There was no significant correlation between IVUS and clinical or laboratory findings. IVUS is a sensitive method for the in vivo detection of CAV, while even severe intimal thickening can often not be identified by CA.(ABSTRACT TRUNCATED AT 250 WORDS)