Prognostic value of dipyridamole thallium-201 screening to minimize perioperative cardiac complications in diabetics undergoing kidney or kidney-pancreas transplantation

Abstract

To minimize perioperative cardiac events, we utilize a screening protocol consisting of intravenous dipyridamole thallium-201 myocardial imaging (DPT), with the selective use of coronary angiography based on the presence of reversible defect(s) on DPT test. A retrospective study was performed to determine the prognostic value of this protocol and to identify any clinical parameters predictive of an abnormal DPT test. To accomplish this, a detailed chart analysis of 176 consecutive kidney (n = 89) and kidney-pancreas (n = 87) transplant recipients who had undergone pretransplant DPT testing was performed. The results of the DPT test were interpreted as normal in 111, fixed defect in 15, and reversible defect(s) in 50 patients. Forty-two of the 50 patients with reversible defect(s) underwent coronary angiography. Twelve of the 27 patients with significant coronary artery disease (CAD, > 50% stenosis in one or more coronary arteries) underwent pretransplant revascularization and the remaining 15 were treated medically. Cardiac events (documented acute myocardial infarction or sudden cardiac death) within 6 wk of transplant were stratified by the results of this protocol. Also, various clinical parameters were compared between patients with normal and abnormal (fixed and reversible defect) DPT tests. Only one of the 111 (0.9%) transplant recipients with a normal DPT test had a perioperative cardiac event. None of the 15 (0%) patients with a fixed defect and none of the 15 (0%) patients with reversible defect(s), but a nonsignificant (< 50% narrowing) coronary angiogram, had a perioperative cardiac event. Three of the 27 (11.1%) patients with reversible defect(s) and significant disease on coronary angiography, who had undergone pre-transplant revascularization or were managed medically, had a perioperative coronary event. Of 14 recipients parameters analyzed, age > 50 yr was the only variable predictive of an abnormal DPT test. We conclude that the incidence of perioperative cardiac events in patients with a normal or fixed defect, or reversible defect(s) but a nonsignificant (< 50% narrowing) coronary angiogram is very low, indicating the high correlation of these findings on DPT and an uneventful (cardiac) post-transplant course. The incidence of perioperative cardiac complications amongst the high-risk transplant recipients with reversible defect(s) and significant CAD on coronary angiogram may be minimized by appropriate preoperative medical management or revascularization. None of the clinical variables except age > 50 yr was predictive of an abnormal DPT test.