Background: Cardiac allograft vasculopathy (CAV) is the major limitation in survival of patients after heart transplantation. Cardiac allograft vasculopathy is angiographically silent in the early phase after operation. Intravascular ultrasound (IVUS) is a more sensitive method to detect the early stages of CAV and provides information about its development. Recent IVUS studies demonstrated a rapid progression of CAV within the first year after transplantation as a predictor of morbidity and mortality.
Objectives: This study assessed the plaque composition of early atherosclerosis in transplant patients by radiofrequency analysis.
Methods: Coronary angiography and IVUS with Virtual Histology (VH) software (Real-Time VH, Volcano Corp, Rancho Cordova, CA) were used to assess 18 patients early after heart transplantation (1.71 +/- 0.47 months). The plaque composition was determined by IVUS radiofrequency data analysis. Tissue maps were reconstructed from radiofrequency data using VH-IVUS software. The VH-IVUS acquisition was performed with standardized IVUS (EagleEye catheter; 2.9 F/20 MHz; Volcano Corp) and the VH-IVUS console (Volcano Corp).
Results: Coronary angiography did not show any wall irregularities. Intravascular ultrasound demonstrated donor-transmitted atherosclerosis in 6 of 18 patients (33.33%). The incidence, amount of plaque burden, and plaque composition was significantly related to donor age. By VH-IVUS analysis, the plaque composition consisted mainly of fibrotic tissue.
Conclusions: Donor-transmitted coronary atherosclerosis is present early after heart transplantation and cannot be detected by coronary angiography. VH-IVUS gives detailed information about the plaque distribution and the plaque composition.