LAUSR

Objective: 6-minute walk test (6-MWT) reflects the daily activity of heart failure (HF) patients who develop progressive limitation of functional capacity (FC). Our aim was to assess different blood pressure (BP) parameters and their changes after 6-MWT in patients with HF with mid-range ejection fraction (EF) (HFmEF) and HF with preserved EF (HFpEF) and correlate them with the FC assessed by 6-minute walk distance (6-MWD). Design and method: Patients presented with clinical manifestations of HF were admitted to Cardiology Department and medically stabilized. 40 HFmEF patients and 50 HFpEF patients underwent 6-MWT according to the American Thoracic Society guidelines 2002. Different BP parameters before and after 6-MWT were recorded including systolic blood pressure, diastolic blood pressure (DBP), mean BP, pulse pressure (PP), and proportionate pulse pressure (PPP) defined as the ratio of PP and SBP. Limited FC was defined as 6-MWD < 300 M. Abnormal BP response to exercise (ABPRE) was defined as a decrease, no increase or an increase of the SBP after exercise by < 20 MMHG. Results: The mean 6-MWD was 325.3 ± 56.84 meters (M), 316.1 ± 61.33 M, 332.66 ± 52.44 M in all patients, HFmEF patients, and HFpEF patients respectively. 6-MWD and limited FC showed no significant difference between the 2 groups. Limited FC affected 42.5 % and 33 % of HFmEF and HFpEF patients respectively. ABPRE affected 28 (31.1 %) of patients and was significantly higher in HFmEF than HFpEF patients. Independent predictors of limited FC were lower EF, PP and PPP and higher DBP in HFmEF patients and lower EF in HFpEF patients. Cut-off points for prediction of limited included PP < 32.5 MMHG and PPP < 30.22 % in HFmEF patients, PP < 37.5 MMHG and PPP < 32.67 % in HFpEF patients, and EF < 42.5 % in all patients (figure 1). Conclusions: The 6-MWT is well tolerated by HF patients and easy to perform in clinical practice. Simple bed-side measurement of BP parameters correlated with the FC and predicted limited FC in HFmEF and HFpEF patients.