One Year Follow-up Of Patients With Chronic Refractory Angina Pectoris Treated With Enhanced External Counterpulsation

Objective The purpose of this study was to assess safety and efficacy of enhanced external counterpulsation(EECP) on chronic refractory angina(RFA) patients, and the long-term outcome of EECP treatment.Method Sixty RAF patients were randomized to EECP group or drug group. The drug group was treated with conventional treatment, and EECP group was treated with conventional treatment combining EECP 30 minutes twice per day for 35 hours. Canadian cardiovascular society(CCS) class, average weekly anginal attack count and nitroglycerin usage were collected before and after EECP treatment. The CCS class was follow-up for one year in EECP group. Plasma levels of endothelin, high-sensitivity C-reactive protein(HS-CRP) were measured before and after EECP treatment. Left ventricular ejection fractions(LVEF), Left ventricular end-systolic diameter(LVESD), Left ventricular end-diastolic diameter(LVEDD) were performed with the use of ultrasound before and after EECP treatment. The number of hospitalizations in the 6 months prior to EECP and the one year follow-up period, the number of major adverse cardiovascular event(MACE) in the one year follow-up period were collected.Results After 35 sessions of EECP, EECP decreased average CCS classification(1.90±0.16) versus(2.93±0.12) in EECP group versus drug group(P<0.05). EECP led to an improvement by at least 1 Canadian Cardiovascular Society(CCS) class in 76.6% patients, by 2 classes in 33.3% patients, by 3 classes in 10% patients. At six months after EECP treatment, 70.0% patients still improved at least 1 class, 30.0% patients still improved 2 classes and 6.7% improved 3 classes. At 12 months after EECP treatment, 66.7% patients still improved 1 class, 30.0% patients still improved 2 classes and 6.7% improved 3 classes. EECP decreased average weekly anginal attack(4.43±3.50 versus 13.29±6.45), nitroglycerin usage(3.16±3.05 versus 12.45±5.39), the level of endothelin(54.43±10.56 versus 68.49±10.26)ng/L, HS-CRP( 2.35±1.84 versus 4.24±1.52) mg/L, whereas it increased LVEF(48.50±12.68 versus 46.20±10.48)% and decreased LVESD(39.70±8.98 versus 37.05±7.38)mm in EECP group versus drug group, respectively(all P<0.05). There were no changes in LVEDD. In the 6-month period before 35 hours of EECP, the hospitalization was 73.3% versus 80%. During the one year follow-up period, EECP decreased hospitalization(43.3% versus 73.3%) and MACE(6.7% versus 26.7%) in EECP group versus drug group, respectively(all P<0.05).Conclusion EECP is a noninvasive, safe and effective technique for chronic refractory angina that not only can reduce CCS classification, angina attacks, nitroglycerin usage, the level of ET and HS-CRP, whereas improve cardiac ejection capacity, but also decrease hospitalization and MACE during the one year follow-up period.