Investigating Gait Speed as the Index of Exercise Tolerance in Heart Failure with Preserved Ejection Fraction

Abstract

Introduction: As an essential factor affecting life prognosis and rehospitalization in patients with chronic heart failure, exercise tolerance is a significant outcome of cardiac rehabilitation. Heart failure with preserved ejection fraction (HFpEF) from reduced diastolic capacity has recently increased among patients with chronic heart failure. This study evaluates the factors indicating exercise tolerance in patients with HFpEF from various perspectives, including cardiac and skeletal muscle functions. Materials and Methods: The subjects were 31 patients with HFpEF who underwent cardiac rehabilitation. The exercise tolerance was assessed using a 6-min walking test. Physical function, physical activity, body composition test, baseline characteristics, blood data, and echocardiography results were extracted from medical records to identify the indicators of exercise tolerance Results: Gait speed significantly differed in exercise tolerance for HFpEF patients (β=0.75, P<0.01). Unlike heart failure with reduced ejection fraction (HFrEF), HFpEF was not significantly different in brain natriuretic peptide levels and cardiac function. Conclusion: Gait speed indicates exercise tolerance in HFpEF patients; however, its pathological course differs from heart failure with reduced ejection fraction, suggesting that it is poorly related to brain natriuretic peptide, a biomarker for heart failure and cardiac function.