Impact of heart transplantation on the safety and feasibility of the dobutamine stress test

Abstract

Background Dobutamine myocardial perfusion imaging is a useful method for evaluation of coronary artery disease. However, this technique does not allow for ischemia monitoring, which may have an impact on the safety of the test in heart transplant recipients due to cardiac sensory denervation. The aim of this study was to assess the impact of heart transplantation on the feasibility and complications of the dobutamine stress test. Methods We studied 225 heart transplant recipients (mean age 57 ± 7 years) and a control group of 225 patients without previous transplant matched for age and gender by dobutamine (up to 40 μg/kg per minute) stress myocardial perfusion imaging. Results During the test, transplant recipients had a lower prevalence of premature ventricular contractions (23% vs 37%, p < 0.001) and ventricular tachycardia (0.04% vs 7.5%, p < 0.0001) compared with control patients. By multivariate analysis, heart transplantation was a powerful independent variable associated with a reduced risk of ventricular arrhythmias (χ 2 = 20.8, p < 0.0001) and minor side effects (nausea, dizziness, anxiety, flushing, chills) (χ 2 = 20, p < 0.0001) during dobutamine stress. The target heart rate was reached in 82% of transplant recipients and in 77% of the control group. Overall feasibility (achievement of the target heart rate and/or an ischemic end-point) was 87% in the transplant and 86% in the control group. Conclusions Dobutamine stress myocardial perfusion imaging is a safe and feasible method for evaluation of coronary artery disease in heart transplant recipients. The prevalence of arrhythmias and minor complications using the dobutamine stress test is lower in heart transplant recipients compared with control patients. The independent association between heart transplantation and reduced risk of arrhythmias and minor side effects of the dobutamine stress test indicates that cardiac sensory and autonomic nerve function plays a major role in the induction of these complications during the test.