High-dose dipyridamole echocardiography test in coronary artery disease after heart transplantation

In order to evaluate the usefulness of the high-dose dipyridamole echocardiography test (DET) for the detection of coronary artery disease (CAD) after heart transplant and for the assessment of prognosis, 80 heart transplant patients underwent this test within 48 h of the scheduled yearly coronary angiography. Coronary angiography showed normal coronary arteries in 55 patients and CAD in 25, eight of whom had > 50% luminal narrowing. Segmental hypokinesis on baseline echocardiography was present in 27 patients, 19 of whom had CAD (sensitivity = 76%; specificity = 85%). DET was negative in all the patients with normal coronary arteries (specificity = 100%). Out of 25 patients with CAD, eight had a positive DET and 17 a negative DET (sensitivity 32%), but DET was positive in seven of the eight patients with coronary artery stenosis > 50% (sensitivity 87%). During follow-up (9.8 +/- 4.5 months) seven cardiac events occurred in seven patients, all with CAD and wall motion hypokinesis (six on baseline echocardiogram and four after dipyridamole infusion). In our experience, DET does not seem adequate for the screening of post-transplant CAD, but useful in identifying patients with severe lesions (> 50%). Wall motion abnormalities on baseline echocardiogram or after dipyridamole infusion might identify patients who require closer surveillance. A longer experience is needed to confirm these results.