Since 1998 the International Enhanced External Counterpulsation Patient Registry (IEPR) has collected data on baseline characteristics,safety and acute and long-term outcome of consecutively enrolled patients undergoing EECP for chronic angina.The majority of patients receiving EECP have severe angina,have had previous revascularization,and are no longer suitable for either bypass surgery or percutaneous intervention.Patients show a high rate of comorbid conditions such as diabetes,and congestive heart failure.After a mean treatment time of 34 hours,72% of patients showed reduction in angina.Major adverse coronary events during treatment period are infrequent.On a sample of patients followed to one year,the majority maintain their reduction in angina without occurrence of any major coronary event.