Adaptações autonômicas e de estresse oxidativo induzidas por um programa de reabilitação cardiopulmonar em coronariopatas

Abstract

Coronary artery disease (CAD) has been associated with reduced physical capacity and quality of life and increased mortality, probably due to cardiac and vascular dysfunction. Studies suggest that such dysfunctions may be associated with impairment in heart rate variability (HRV) and increased oxidative stress. On the other hand, it is well evidenced the importance of regular physical exercise in the improvement of these parameters in several populations. Therefore, the aim of the present study was to evaluate the effects of cardiopulmonary rehabilitation (CPR) on autonomic dysfunction and oxidative stress and its impact on the physical capacity and quality of life of coronary patients under beta blockers treatment. We included 10 patients with coronary artery disease using a beta-blocker who participated in a CPR program composed of 30-36 sessions of aerobic and resisted exercises. RR interval recording was performed with an electrocardiogram for HRV analysis. Blood collection was performed with the subject in a 12-hour fast for evaluation of oxidative stress. The cardiopulmonary test was performed on an ergometric treadmill with a ramp protocol. Quality of life (SF36), level of physical activity (IPAQ) and level of perceived stress were evaluated. After CPR, there was improvement in HRV, characterized by reduction of the sympatho/vagal balance [LF/HF: pre 1.76 (1.18 - 5.92) vs. post 1.05 (0.83 - 3.38)] and the cardiac parasympathetic modulation [RMSSD: pre 24.40 (20.36 – 26.86) vs. post 28.02 (24.05 – 34.40) ms], improvement of the oxidative stress parameters [protein oxidation: 1.02 (0.97-1.08) vs. post 0.87 (0.76-0.92) nmol/mg protein; hydrogen peroxide: pre 26.08 (19.05 - 50.60) vs. post 15.94 (10.94 - 20.94) μM and FRAP: pre 0.95 (0.59 - 1.07) vs. post 1.15 (1.03 - 1.36) mM Fe (ii)]. These changes were accompanied by improvement in physical capacity (VO2peak: pre 22.9 (21.2 - 24.9) vs. post 25.9 (24.1 - 28.3) ml/min/kg) and quality of life. Our results show an improvement in the HRV and in the systemic oxidative stress that are probably associated with an improvement in functional capacity and quality of life in coronary patients after a cardiopulmonary rehabilitation program.