Comportamento hemodinâmico e resposta cronotrópica da frequência cardíaca durante o teste de caminhada de 6 minutos em pacientes com hipertensão pulmonar

Abstract

Introduction: Pulmonary Hypertension (PH) is a pathophysiological disorder that can involve multiple clinical conditions and it is defined by a mean pulmonary arterial pressure (mPAP) > 20 mmHg at rest, by a pulmonary vascular resistance (PVR) > 2 Wood Units (WU) and by a pulmonary arterial occlusion pressure ≤ 15 mmHg. Its definitions are based on hemodynamic assessment by right heart catheterization, and can be categorized into five groups: (1) pulmonary arterial hypertension; (2) PH associated with left heart disease; (3) PH due to lung disease and/or hypoxia; (4) PH related to chronic thromboembolism; and (5) PH with uncertain and/or multifactorial mechanisms. The exacerbated blood pressure response associated with greater peripheral vascular resistance and the failure to fall in heart rate after cessation of exertion have been linked to increased mortality in a variety of conditions and clinical scenarios. Objective: To analyze the hemodynamic behavior during the 6-minute Walk Test, the recovery of heart rate and its correlation with the distance covered in patients diagnosed with Pulmonary Hypertension. Methods: This is a cross-sectional observational analytical study, carried out at the Cardiac Rehabilitation Unit of the Onofre Lopes University Hospital. Patients diagnosed with PH, clinically stable, referred from the HUOL Pulmonology and Cardiology outpatient clinic were included. Everyone performed the Six-Minute Walk Test (6MWT) in accordance with the ATS recommendation. A correlation was made between hemodynamic data of blood pressure (BP) and heart rate (HR), and recovery HR in the second minute with the distance covered in the 6MWT. Results: The sample of this study consisted of 52 individuals, with a mean age of 43.77 土 15.0 years. 46 of whom were female. A positive correlation was found between the functional performance of the 6MWT vs systolic blood pressure at the end of the test (r=0.41; p=0.02) and vs HR in the sixth minute (r=0.40; p=0. 01). The distance covered in the 6MWT did not show significant correlations with recovery HR (r = 0.20; p = 0.15). (r=0,40; p=0,01). The distance covered in six minutes did not show significant correlations with recovery HR (r=0,20; p=0,15). Final considerations: It was observed in this study that, in the sample studied, this population presented a low chronotropic capacity for HR adaptation.