INCIDENCE AND SEVERITY OF TRANSPLANT CORONARY-ARTERY DISEASE EARLY AND UP TO 15 YEARS AFTER TRANSPLANTATION AS DETECTED BY INTRAVASCULAR ULTRASOUND

Objectives. The purpose of this study was to quantify the severity of transplant coronary artery disease and to assess lesion characteristic s early and up to 15 years after heart transplantation by using intrac oronary ultrasound. Background. Intravascular ultrasound has the abili ty to measure the components of the arterial wall and has been shown t o be a sensitive method for detection of transplant coronary artery di sease. Methods. A total of 304 intracoronary ultrasound studies were p erformed in 174 heart transplant recipients at baseline and up to 15 ( mean 3.3 +/- 0.2) years after transplantation. Mean intimal thickness and an intimal index were calculated, and lesion characteristics (ecce ntricity, calcification) were assessed for all coronary sites imaged ( mean 3.0 +/- 0.1 sites/study). The Stanford classification was used to grade lesion severity. Results. Compared with findings in patients st udied at baseline (<2 months after transplantation, n = 50), mean inti mal thickness (0.09 +/- 0.02 vs. 0.16 +/- 0.02 mm, p < 0.01), intimal index (0.07 +/- 0.01 vs. 0.14 +/- 0.02, p < 0.01) and mean severity cl ass (1.5 +/- 0.2 vs. 2.3 +/- 0.2, p < 0.01) were significantly higher at year 1 (n = 52) after transplantation, Thereafter, all three variab les further increased over time and reached highest values between yea rs 5 and 15. Calcification of lesions was detected in 2% to 12% of stu dies up to 5 years after transplantation, with a significant increase to 24% at years 6 to 10 (p < 0.05). Conclusions. Severity of transplan t coronary artery disease appeared to progress with time after transpl antation in this cross-sectional study. This characteristic was most p rominent during the Ist 2 years after transplantation, whereas calcifi cation of plaques occurred to a significant extent only later in the p rocess. These data may serve as a reference for comparison of intravas cular ultrasound findings in other studies of patients with transplant coronary artery disease.