Does the 6-minute walk test predict the prognosis in patients with NYHA class II or III chronic heart failure?

Exercise testing in pulmonary arterial hypertension and in chronic heart failure

“…Previous studies have shown that advanced PAH and CHF are both characterised by decreased peak work-rate, peak V9O 2 , V9O 2 at the anaerobic threshold and peak oxygen pulse, and increased ventilatory equivalents [2][3][4][5][6][7][9][10][11][12][13]. In the present patients, the anaerobic threshold occurred at a higher percentage of peak V9O 2 than in normal subjects.…”

“…In the face of these limits of normal, it appears that both the present PAH and CHF patients frequently exhibited an abnormally prolonged cardiac frequency recovery. The mechanisms of prolonged cardiac frequency recovery after exercise in cardiac patients remain incompletely understood [13].…”

“…Chronic heart failure (CHF) is characterised by impairment of cardiac output adaptation to peripheral oxygen requirements, and also results in altered cardiopulmonary exercise testing variables and decreased 6-min walking distances, which correlate better with NYHAFC and prognosis than with resting invasive or noninvasive measurements of cardiac function [9][10][11][12][13].…”

Insuficiência cardíaca: comparação entre o teste de caminhada de seis minutos e o teste cardiopulmonar

“…In the study by Lucas et al 12 conducted with 307 patients with advanced HF (ejection fraction < 35%), peak VO 2 reached in symptom-limited CPET, applied in a subgroup of 213 patients with a peak VO 2 between 10 to 20 ml/kg/min showed a low correlation with the DW in the 6MWT' (r = 0.28). In another study, Roul et al 19 , also conducted in 121 patients with HF (functional classes NYHA-II-III, ejection fraction 29.6% ± 13%) demonstrated a low correlation between the peak VO 2 in symptom-limited CEPT, and DW in the 6MWT' (r = 0.24).…”

“…Some studies have shown that a value smaller than or equal to 300 meters in six minutes indicates a worse prognosis compared with patients walking more than 300 meters 10,19 . Our study was able to show that two critical variables, the DW in 6MWT' and peak VO 2 in the CPET have a correlation at a moderate level and statistically significant at peak exertion in patients with HF functional class I -II (r = 0.70; p = 0.002).…”