Longitudinal study of vascular remodeling in coronary arteries after hearttransplantation

Background: Cross-sectional studies by intravascular ultrasound (IVUS) in h eart transplant recipients have suggested that vascular remodeling occurs i n coronary arteries years after transplant. However, no reports describe va scular remodeling in the same cohort of patients studied prospectively usin g morphometric analysis (10 evenly spaced images obtained from a slow pullb ack from the left anterior descending coronary artery). Morphometric analys is better reflects total vessel anatomy compared with previously reported s ite (2 to 3 images) analysis. Methods: We reviewed 20 patients studied by IVUS at 2 months, 1 year, 2 yea rs, and 3 years after heart transplant. Results: Over time, the coronary artery luminal area decreased from baselin e level of 12.0 mm(2) to a 3-year mark of 9.7 mm(2) (p = 0.02). Vessel shri nkage was seen in 16/20 patients. After an initial rise in intimal paramete rs (maximal intimal thickness, intimal index, and plaque area) from baselin e to 1 year, we found a significant decrease in intimal parameters between Year 1 and Year 3 after transplant. For example, plaque area decreased from 2.05 mm(2) at 1 year post-transplant to 1.48 mm(2) by 3 years posttranspla nt (p = 0.05). Conclusion: In a majority of heart transplant patients, early intimal thick ening in the first year post-transplant is accompanied by constrictive remo deling. Over the subsequent 2 years, further constrictive remodeling is see n despite a decrease in intimal area.