What is the efficacy of EECP in treating stable angina pectoris?
The efficacy of EECP in treating stable angina pectoris has been evaluated in a single randomized controlled trial (RCT) and several observational registry studies. MUST-EECP (Multicenter Study of Enhanced External Counterpulsation) found that time to $1-mm ST-segment depression increased significantly in patients treated with active counterpulsation compared with placebo, although there was no difference between the groups in exercise duration. A meta-analysis of 13 observational studies that tracked 949 patients found that anginal class as categorized by the CCS classification was improved by $1 class in 86% of patients. The EECP Consortium and International EECP Registry also reported improvement of $1 angina class in 81% and 86% of patients respectively. Overall, the existing data suggest a benefit from EECP in patients with angina refractory to other therapy, although additional data from well-designed RCTs are needed to better define the role of this therapeutic strategy. 