Influência da força muscular inspiratória na capacidade funcional e qualidade de vida de pacientes submetidos à revascularização do miocárdio

Abstract

The myocardial revascularization (CABG) surgery is a complex procedure that entails clinical and functional complications, especially on the pulmonary system. Among these, the reduction of inspiratory muscle strength that persists even late is highlighted and has been suggested as a determinant of functional capacity. The objective of this study was to verify if the inspiratory muscle strength exerts an influence on the functional capacity and QoL of post-CRP patients inserted in cardiac rehabilitation (CR) - Phase II. This is a prospective, quasi-experimental study involving 24 post-CABG patients submitted to aerobic, resisted and inspiratory muscle training (IMT) for 12 weeks, twice a week. Before and after the following evaluations were performed: inspiratory muscle strength (maximal inspiratory pressure - MIP) through manovacuometry; (maximum exercise peak oxygen consumption - peak VO2) through cardiopulmonary exercise test; submaximal functional capacity using the six-minute walk test (6MWT) and QoL by the Minnesota Living with Heart Failure Questionnaire (MLHFQ). Before CR program, the MIP had a moderate positive correlation with the peak VO2 (r=0.678, p=0.003) and the 6MWT (r = 0.439, p=0.031). However, no correlation was observed with QoL (r=0.015, p=0.942). There was a strong positive correlation between MIP and peak VO2 (r=0.753, p <0.001) and MIP was positively and moderately correlated with the 6MWT (r=0.520, p=0.009) and negative and moderately with QoL (r=0.456, p =0.025) after the CR program. The present study demonstrated that inspiratory muscle strength is a determinant of functional capacity and QoL in post-CR patients inserted in Phase II of CR.