Prognostic value of dobutamine stress echocardiography for the long-term outcomes in kidney transplant candidates

Background: Cardiovascular disease is a primary cause of morbidity and mortality in kidney transplant (KT) candidates. Dobutamine stress echocardiography (DSE) is an effective noninvasive modality for evaluating coronary artery disease with high accuracy. However, long-term data in KT candidates are still lacking. This study aims to assess the prognostic value of DSE in predicting long-term outcomes in KT candidates. Methods: This study retrospectively included consecutive KT candidates who underwent preoperative DSE between 2007 and 2017 at Siriraj Hospital, Bangkok, Thailand. Normal DSE was characterized by the absence of wall motion abnormalities both at rest and during stress. The primary endpoint was all- cause mortality. Univariable and multivariable analyses were conducted to determine predictors of all-cause mortality, with a P value of <0.05 considered statistically significant. Results: Among 269 patients (mean age 51 years, 58% male), 34 (12.6%) had abnormal DSE results, and 63 (23%) underwent kidney transplantation after DSE. During a median follow-up period of 7.6 (4.5, 10.1) years, 129 (48%) patients died. Patients with abnormal DSE had a significantly higher mortality rate than those with normal DSE (73.5% vs. 44.2%, P=0.003). Univariable analysis demonstrated that male gender [hazard ratio (HR) 1.50, 95% confidence interval (CI): 1.04-2.16, P=0.03], resting systolic blood pressure (HR 1.006, 95% CI: 1.00-1.01, P=0.04), abnormal DSE (HR 1.95, 95% CI: 1.25-3.05, P=0.003), higher delta wall motion score index (HR 2.57, 95% CI: 1.24-5.35, P=0.01), abnormal stress left ventricular end- systolic volume (HR 2.05, 95% CI: 1.11-3.82, P=0.02), and post-KT status (HR 0.48, 95% CI: 0.30-0.79, P=0.004) were associated with mortality. In the multivariable analysis, male gender and abnormal DSE were independent predictors of mortality [adjusted HR (aHR) 1.65, 95% CI: 1.06-2.20, P=0.02 and aHR 1.88, 95% CI: 1.20-2.93, P=0.006, respectively], while post-KT status emerged as an independent predictor of better outcomes (aHR 0.47, 95% CI: 0.29-0.77, P=0.003). Conclusions: In KT candidates, preoperative assessment with DSE provides valuable prognostic information for long-term outcomes, particularly regarding all-cause mortality.