Abstract 10754: Dobutamine Stress Real Time Perfusion Echocardiography Identifies Significant Coronary Artery Disease and Predicts Outcome in Patients With End Stage Renal Disease Undergoing Transplant Evaluation

Abstract

Background: The utility of dobutamine stress real time perfusion echocardiography (DS-RTPE) to identify patients with coronary artery disease (CAD) and predict outcomes has been well validated. However, end stage renal disease (ESRD) patients undergoing renal transplant evaluation represent a challenging cohort since most studies have found stress imaging to be suboptimal at predicting significant CAD. Therefore, despite current guidelines, most transplant centers refer high risk patients for coronary angiography (CA). The purpose of this study was to assess the predictive value of DS-RTPE in this high risk cohort.

Methods: We performed a retrospective analysis of all potential renal transplant recipients from 2006-2008 that had DS-RTPE. Wall motion and perfusion data from the DS-RTPE, were compared with cardiac catheterization and outcome data. Since age is a known predictor of outcome, analysis was performed to the determine the predictive value of DS-RTPE as a function of age and resting ejection fraction (EF). Positive (PPV) and Negative (NPV) preditive values were assessed for a) the ability to detect CAD by CA, and b) predict outcome.

Results: A total of 234 patients (mean age 51+/-10 years) had DS-RTPE for renal transplant evaluation. Of these, 123 underwent CA. The sensitivity and specificity of DS-RTPE for detection of >60% stenosis at CA was 91 and 76% respectively (PPV 71, NPV 93 and accuracy 82%). A total of 218 patients were followed for up to three years following DS-RTPE. There were a total of 61 events (54 deaths and 17 non fatal cardiac events). For predicting events, DS-RTPE had sensitivity, specificity, PPV and NPV of 47, 75, 42, and 78% respectively, which was equivalent to CA (59, 69, 44, and 80% respectively). Although age was the most important variable (p<0.001), both the presence of diabetes (p=0.04) and DS-RTPE (p=0.04) added significant predictive value, with higher PPV for predicting events as age increased.

Conclusion: DS-RTPE is predictive of significant CAD and equivalent to CA in predicting outcome in patients with ESRD. DS-RTPE has the additional utility to predict events beyond traditional risk factors, age and EF. Patients with normal DS-RTPE should not be referred for CA given the added risk and lack of additional predictive value.