Correlation of 6‐min walk test with left ventricular function and quality of life in heart failure due to Chagas disease

Objectives To evaluate the correlation of the total distance walked during the six‐minute walk test (6MWT) with left ventricular function and quality of life in patients with Chagas Disease (ChD) complicated by heart failure. Methods This is a cross‐sectional study of adult patients with ChD and heart failure diagnosed based on Framingham criteria. 6MWT was performed following international guidelines. New York Heart Association functional class, brain natriuretic peptide (BNP) serum levels, echocardiographic parameters and quality of life (SF‐36 and MLHFQ questionnaires) were determined and their correlation with the distance covered at the 6MWT was tested. Results Forty adult patients (19 male; 60 ± 12 years old) with ChD and heart failure were included in this study. The mean left ventricular ejection fraction was 35 ± 12%. Only two patients (5%) ceased walking before 6 min had elapsed. There were no cardiac events during the test. The average distance covered was 337 ± 105 metres. The distance covered presented a negative correlation with BNP (r = −0.37; P = 0.02), MLHFQ quality‐of‐life score (r = −0.54; P = 0.002), pulmonary artery systolic pressure (r = −0.42; P = 0.02) and the degree of diastolic dysfunction (r = −0.36; P = 0.03) and mitral regurgitation (r = −0.53; P = 0.0006) and positive correlation with several domains of the SF‐36 questionnaire. Conclusions The distance walked during the 6MWT correlates with BNP, quality of life and parameters of left ventricular diastolic function in ChD patients with heart failure. We propose this test to be adopted in endemic areas with limited resources to aid in the identification of patients who need referral for tertiary centres for further evaluation and treatment. Objectifs Evaluer la corrélation de la distance totale parcourue durant le test de marche de 6 minutes (6 MWT) avec la fonction ventriculaire gauche et qualité de vie chez les patients atteints de la maladie de Chagas (MCh) compliquée par une insuffisance cardiaque. Méthodes Etude transversale sur des patients adultes atteints de la MCh et d'une insuffisance cardiaque, diagnostiqués selon les critères de Framingham. Le test 6MWT a été effectué selon les directives internationales. La classe fonctionnelle de la New York Heart Association, les taux sériques du peptide natriurétique du cerveau, les paramètres échocardiographiques et la qualité de vie (questionnaires SF‐36 et MLHFQ) ont été déterminés et leur corrélation avec la distance parcouru