Early Atherosclerosis Following Heart Transplantation: An Intravascular Ultrasonography Study

There are several invasive and noninvasive techniques investigating the development of coronary artey disease following heart transplantation (TxCAD). This study attempts to investigate the extent of vasculopathy in heart transplant recipients by using intravascular ultrasonography (IVUS) compared to coronary angiography and to define the relationship between the rate of cellular rejection and intimal coronary thickness which is measured by IVUS. Our study is the first experience in Turkey. To investigate the extent of TxCAD, 18 heart transplant recipients were studied for 22±12 months after transplantation with intravascular ultrasound (IVUS). Dobutamine stress echocardiography (DES) and coronary angiography were performed in all patients. Coronary angiographically narrowing of more than 50% and intimal wall thickness >0.5mm detected by IVUS were defined as TxCAD. Biopsy score was considered as the average numerical value assigned to each grade of rejection divided by the total number of biopsies. According to the IVUS findings the patients were evaluated in two groups. There were 8 patients with TxCAD in group I, and group II consisted of 10 patients without TxCAD. The TxCAD was shown in 5.5% patients angiographically whereas this rate was 44% by IVUS. The results of DES were normal in all patients. The extent of coronary vessel wall alterations on ultrasound correlated with donor age (r=0.42, p=0.02), but not with perioperative ischemia time and other coronary artery risk factors (p>0.05). The intimal thickening was more pronounced in segments of the LAD than the other arteries (p<0.001). The value of biopsy score (the mean grade of rejection) demonstrated a correlation with the mean intimal thickening (r = 0.82, p = 0.01).
CONCLUSION
1) The rate of cellular rejection is an important factor for developing TxCAD. 2) IVUS is a more sensitive method for detection of TxCAD than coronary angiography. (Türk Kardiyol Dern Arş 2004; 32: 288-294)