Correlação entre a função pulmonar e o teste de caminhada de seis minutos em pacientes com hipertensão pulmonar

Abstract

Introduction: Pulmonary Hypertension (PH) consists of a heterogeneous health condition, which involves different hemodynamic changes that affect pulmonary circulation, which cause an increase in mean pulmonary arterial pressure (mPAP) ≥ 20 mmHg at rest. Patients with PH present mainly symptoms of dyspnea during efforts, fatigue, and muscle weakness, which directly affects the subject's functionality. Although many patients present changes in lung function, studies that correlate with functional performance are still limited. Aim: To analyze the correlation between pulmonary function (spirometry and maximal respiratory pressures) and the performance in a 6-minute walk test (6MWT) in patients with PH. Methodology: It’s an observational analytical cross-sectional study, with patients diagnosed with PH, over 18 years old, followed by a pulmonologist and/or cardiologist at HUOL/UFRN, and without exacerbation of the clinical condition in the last three months. There were two days of evaluation, in which the first addressed respiratory function tests (spirometry and maximal respiratory pressures), while on the second day, the 6MWT was performed. Results: In total, 15 women were evaluated on the two days of testing, with an average of 43 years (43,47 ± 14,58), classified as PH type I (14) or PH type IV (1), and functionally (WHO-FC) 11 as class II, 3 as class III and only one as class I. When analyzing the correlation between pulmonary function variables and the 6MWT, a moderate positive correlation was observed with MVV% (r = 0,54 and p = 0,03) and MEP (r = 0.55 and p = 0.03). No other correlations were found. Conclusion: Patients with PH manifest a decrease in pulmonary function values concomitantly with a reduction in the distance covered in the 6MWT, which may indicate that changes in resistance and strength of the respiratory muscles may also express a worse evolution of the disease, as well as being a marker for risk stratification in the HP.