Oxygen Consumption Changes During EECP Treatment in Patients with and without Coronary Artery Disease

Abstract

1475 BACKGROUND: Enhanced External Counterpulsation (EECP) therapy has been found to be effective in increasing functional capacity and improving angina in patients with symptomatic coronary artery disease who are unable to undergo traditional revascularization procedures. It has been hypothesized that repetitive treatments of EECP may condition the cardiac and skeletal muscle, enhancing the ability of the muscles to more efficiently utilize consumed oxygen. PURPOSE: To determine the acute oxygen consumption (VO2) responses to EECP therapy, we evaluated VO2 responses during a single EECP therapy session in subjects with and without known coronary artery disease. METHODS: Twelve subjects (8 men, 4 women, mean +/− SD age = 50 +/− 18) volunteered to participate in the study. This group consisted of 7 healthy, sedentary individuals and 5 coronary artery disease patients. EECP treatment was performed using the TS3 EECP system (Vasomedical Corp, Westbury, NY) in conjunction with concomitant VO2 measurement (MedGraphics CPX/D, Medical Graphics Corp, Minneapolis, MN). VO2 was measured continuously throughout a 10-minute rest period, a 30-minute EECP protocol, and 10-minute recovery period. RESULTS: EECP therapy resulted in statistically significant increases (0.58 +/− 0.31 ml/kg/min; P = 0.0001) in VO2 as compared to those measured at rest. In addition, a significant decrease (−0.57 +/− 0.25 ml/kg/min; P = 0.0001) in VO2 was observed immediately following the cessation of therapy and throughout the recovery period. Intergroup comparisons showed cardiac patients to be older (P = 0.02), have higher body fat percentage (P = 0.03) and lower VO2 during EECP treatment (P = 0.05) as compared to their healthy counterparts. CONCLUSION: EECP therapy results in significant increases in somatic oxygen consumption as compared to measured resting and recovery levels. These finding highlight the potential significance of VO2 improvement as the mechanism underlying the benefits seen with EECP therapy.