Enhanced external counterpulsation in the treatment of chronic refractory angina: A long-term follow-up outcome from the international enhanced external counterpulsation patient registry

Background: The management of patients who suffer from medically refractory angina and are unsuitable for conventional revascularization therapy is often unsatisfactory. Enhanced external counterpulsation (EECP) is a noninvasive treatment that is safe and effective immediately after a course of treatment. However, the duration of benefit is less certain. Hypothesis: To evaluate the 3-year outcome of EECP treatment. Methods: One thousand four hundred and twenty seven patients from 36 centers registered in the International EECP Patient Registry (IEPR) - Phase 1 was prospectively followed for a median of 37 months. Two hundred and twenty patients (15.4%) died, while 1,061 patients (74.4%) completed their follow-up. Results: The mean age was 66 ± 11 years and 72% were men. Seventy-six percent had multivessel coronary disease for 11 ± 8 years. Eighty-eight percent had a prior percutaneous or surgical revascularization and 82% were unsuitable for further coronary intervention. Immediately post-EECP, the proportion of patients with severe angina (Canadian Cardiovascular Angina Classification [CCS] III/IV) were reduced from 89% to 25%, p<0.001. The CCS class was improved by at least 1 class in 78% of the patients and by at least 2 classes in 38%. This was sustained in 74% of the patients during follow-up. Thirty-six percent of the patients had CCS II or less angina, which was better than pre-EECP state without a major adverse cardiovascular event during follow-up. More severe baseline angina and a history of heart failure or diabetes were independent predictors of unfavorable outcome. Conclusion: An EECP improves angina and quality of life immediately after a course of treatment. For most of the patients, these beneficial effects are sustained for 3 years.