Effects of Enhanced External Counterpulsation on Heart Rate Recovery in Patients with Coronary Artery Disease
Background: Enhanced external counterpulsation (EECP) reduces angina pectoris, extends time to exercise-induced ischemia, and improves quality of life in patients with symptomatic stable angina. We aimed to evaluate the effects of EECP on heart rate recovery in patients with coronary artery disease (CAD).
Methods: Between January 2011 and March 2013, a total of 34 consecutive patients (24 male, 70.6%) with symptomatic CAD, who were candidated for EECP, prospectively received 35 sessions of 1-hour EECP therapy per day, 6 days per week. The patients underwent echocardiography and a symptom-limited modified Bruce exercise test before and after EECP. Left ventricular ejection fraction (LVEF), resting and peak exercise heart rates, systolic blood pressure, heart rate at 1 and 2 minutes of recovery, exercise duration, workload, and first- and second-minute heart rate recovery were measured before EECP and compared with those after EECP.
Results: The mean age of the patients (70.6% men) was 64.82 ± 8.28 years. After EECP, exercise duration increased significantly from 6.48 ± 2.76 minutes to 9.20 ± 2.71 minutes (p value < 0.001). Maximum workload increased significantly (4.44 ± 1.28 vs. 5.65 ± 1.77 METS; p value < 0.001). The LVEF increased from 42.65 ± 11.82% to 44.26 ± 11.86% (p value < 0.001). The resting systolic blood pressure decreased significantly from 125.59 ± 22.35 mmHg to 116.26 ± 14.93 mmHg (p value = 0.013). The increase in the first- and second-minute heart rate recovery after EECP was not statistically significant.
Conclusion: The results of the present study showed that exercise duration, maximum workload, and the LVEF might increase significantly after EECP. The increase in the first- and second-minute heart rate recovery after EECP was not statistically significant.