Inspiratory Muscle Training Reduces Heart Anxiety in Patients Submitted to Coronary Artery Bypass Grafting: Controlled Randomized Clinical Trial

Abstract

Introduction:Cardiac anxiety(CA) is a common finding in patients in the pre- and postoperative period of coronary artery bypass graft(CABG) surgery. Ventilatory restriction generated by pain and reduced muscle strength is associated with increased CA level. Inspiratory muscle training(IMT) for generating increased muscle strength can cause a decrease in CA in the postoperative period. Objective:To evaluate the impact of IMT on inspiratory muscle strength and its relationship with cardiac anxiety in patients undergoing CABG. Methodology:This is a randomized controlled clinical trial. In the preoperative moment, all patients answered a cardiac anxiety questionnaire, composed of two domains: fear and vigilance and avoidance. In addition, their maximum inspiratory pressure(MIP) was assessed. After the surgical procedure, the patients were divided into a control group(CG) that received routine hospital care and a training group(TG) who underwent an IMT protocol until the moment of hospital discharge. Results:80 patients were evaluated,40 in each group. The IMT group showed a 17% decrease in MIP while the CG decreased 43%(p <0.01). The fear and vigilance domain had a decrease of -16±3 in the CG while in the TG the reduction was -8±3(p <0.01). The avoidance domain reduced -17±4 in the CG vs -10±4 in the TG(p <0.01). In addition, there was a strong correlation between the MIP of the TG with the domains of fear/vigilance(r -0.77) and avoidance(r -0.72). Conclusion:IMT is associated with a reduction in the loss of inspiratory muscle strength, resulting in a reduced level of cardiac anxiety in patients undergoing CABG.