Dobutamine cardiolite® stress testing with low-level treadmill exercise demonstrates improved image quality, less medication and fewer patient side effects

Some form of exercise is helpful to achieve target heart rate (THR) in patients undergoing dobutamine Technetium-99 Sestamibi (Cardiolite®) stress tests. The outcomes of low-level exercise (slow treadmill walking) and isometric exercises to achieve THR during dobutamine Cardiolite® stress tests have not been examined. The purpose of this study was to determine if patients who walked on a treadmill during their dobutamine Cardiolite® stress test had better outcomes than those who used isometric exercises. The outcomes measured were the amount of dobutamine and atropine sulfate (atropine) used, duration of dobutamine infusion and quality of cardiac images. A convenience sample of 30 patients per group who required a dobutamine Cardiolite® stress test was recruited from April to September, 2008. Descriptive statistics were reported for each group. The subjects who walked on the treadmill required a lower dose of dobutamine (P = 0.028) and a decreased time of dobutamine infusion (P = 0.031) to achieve their target heart rate. Heart-to-liver ratio results (P = 0.08) and image quality (P < 0.0001) were better with the subjects who walked on the treadmill. No difference in atropine usage was found in either group. These outcomes suggest that the patient who walked on a treadmill during the dobutamine Cardiolite® stress test achieved the target heart rate faster, required less dobutamine and had better image quality than those who performed isometric exercises.