Ischaemia imaging in type 2 diabetic kidney transplant candidates--is coronary angiography essential?

Coronary artery disease (CAD) remains the leading cause of death in type 2 diabetes mellitus (DM) patients undergoing renal transplantation. There is a high prevalence of silent CAD in these patients. Controversy exists regarding the role of dobutamine stress echocardiography (DSE) in detection of CAD. Our purpose was to compare DSE with coronary angiography (CA) for the detection of CAD in type 2 diabetic patients undergoing evaluation for renal transplantation.

Forty (36 male, four female) type 2 diabetic patients with end-stage renal disease (ESRD) were subjected to DSE followed by CA as a part of their pre-renal transplant evaluation. The ability of DSE to predict 70% stenosis in one or more coronary arteries as determined by CA was evaluated. Mean age of the patients was 49.2 +/- 5 years (range 39-60 years).

DSE was positive in 10 (25%) patients, while 19 patients (48%) had a more than 70% lesion in at least one epicardial vessel on CA (six patients had single vessel, three had double vessel and 10 had triple vessel disease). The sensitivity and specificity in identifying CAD was 47.3 and 95.2%, respectively, while positive predictive value and negative predictive value was 90% and 66%. Accuracy of DSE was 72.5%. All four patients with diffuse diabetic coronary artery disease had negative DSE.

DSE is a poor predictor of coronary artery disease in type 2 DM patients being evaluated for renal transplantation. CA should be included in evaluation of type 2 diabetic patients who are renal transplant candidates.