Aim: To study the long-term effect of enhanced external counterpulsation (EECP) therapy on exercise tolerance, quality of life (QoL), and indicators of the structural and functional state of the cardiovascular system in patients with stable ischemic heart disease (IHD) complicated by chronic heart failure (CHF).
Material and methods: This open randomized EXCEL study included 120 patients with verified IHD complicated by NYHA II-III functional class CHF with reduced or mid-range left ventricular (LV) ejection fraction. Patients were randomized into group 1 (n=40), optimal drug therapy (ODT) and EECP (35 hours, 2 courses per year); group 2 (n=40), ODT and EECP (35 hours, 1 course per year); and group 3 (control; n=40), ODT and placebo counterpulsation (35 h, 1 course per year). All patients underwent a 6-minute walk test (6MWT), evaluation of clinical status, QoL with the MLHFQ and SF-36 questionnaires, structural and functional state of large blood vessels and microvasculature, measurement of brain natriuretic peptide precursor (NT-proBNP), and echocardiography at baseline and after 12 months.
Results: In groups 1 and 2 after 12 months, the 6MWT distance increased statistically significantly (44.5 and 24.9%, respectively) and the following indexes improved: QoL (SF-36, MLHFQ), the condition of large blood vessels (phase shift, radial augmentation index, central aortic systolic pressure (CASP)) and microvasculature (occlusion index, percentage of perfused capillaries, percentage of capillary recovery), and the LV systolic function (from 40.6±7.5 to 47.5±10.2% and from 41.3± 6.8 to 43.9±10.3%, respectively). The proportion of patients with a >20% increase in the 6MWT at 12 months was 97.5, 72.5, and 7.7%, respectively. A statistically significant decrease in NT-proBNP was observed in all groups. In group 3, the incidence of hospitalizations for CHF and the risk of the composite endpoint were significantly higher.
Conclusion: For the 12-month study period, the effects of EECP in patients with IHD complicated by CHF included improvements in exercise tolerance, QoL, vascular and cardiac functional parameters, and a decrease in the incidence of adverse outcomes.