Different determinants of exercise capacity in HFpEF compared to HFrEF

Area of Science:

• Cardiology
• Echocardiography
• Heart Failure Research

Background:

• Quality of life is crucial for heart failure (HF) patients, alongside survival.
• Echocardiographic predictors of exercise capacity in HF, especially HF with preserved ejection fraction (HFpEF), remain debated.

Purpose of the Study:

• To prospectively investigate echocardiographic parameters correlating with and predicting exercise capacity in HFpEF patients.
• To identify specific echocardiographic determinants of functional exercise capacity using the 6-minute walk test (6-MWT).

Main Methods:

• Conducted echo-Doppler studies and 6-MWT on the same day for 111 HF patients.
• Classified patients into two groups based on 6-MWT distance (≤300m vs. >300m).
• Analyzed echocardiographic parameters and clinical data to identify predictors of exercise capacity.

Main Results:

• In HFpEF, larger left atrial diameter and diabetes independently predicted poorer 6-MWT performance.
• In HFrEF, older age and larger left atrial diameter were associated with reduced exercise capacity.
• In HFpEF, impaired longitudinal systolic function (lateral s') and lower hemoglobin levels independently predicted poorer 6-MWT performance.

Conclusions:

• Determinants of exercise capacity in HF patients vary based on left ventricular (LV) systolic function severity.
• Left atrial enlargement is a key determinant in HFrEF, while longitudinal systolic shortening is critical in HFpEF.
• These findings highlight distinct echocardiographic markers for functional capacity in different HF phenotypes.