Moderate continuous or high intensity interval exercise in heart failure with reduced ejection fraction: Differences...

Area of Science:

• Cardiology
• Exercise Physiology
• Heart Failure Research

Background:

• Exercise is recommended for heart failure with reduced ejection fraction (HFrEF).
• Current guidelines do not differentiate exercise modes or intensities based on heart failure etiology.
• The impact of exercise intensity on different heart failure etiologies remains unclear.

Purpose of the Study:

• To investigate the effects of moderate versus high-intensity exercise on cardiac function and exercise capacity in HFrEF patients.
• To compare outcomes between patients with ischemic cardiomyopathy (ICM) and non-ischemic cardiomyopathy (NICM).

Main Methods:

• The SMARTEX-HF trial enrolled 231 HFrEF patients in a 12-week supervised exercise program.
• Patients were randomized to moderate continuous training (MCT), high-intensity interval training (HIIIT), or recommendation of regular exercise (RRE).
• Left ventricular end-diastolic diameter (LVEDD), ejection fraction (LVEF), and peak oxygen consumption (peak VO2) were assessed at baseline, 12, and 52 weeks.

Main Results:

• Etiology (ICM vs. NICM) did not influence changes in LVEDD or LVEF after 12 or 52 weeks.
• Patients with ICM had lower baseline and 12-week peak VO2 compared to NICM patients, but exercise training did not alter this difference.
• Neither moderate nor high-intensity exercise showed differential effects based on HFrEF etiology.

Conclusions:

• The etiology of HFrEF does not affect the response to moderate or high-intensity exercise.
• Exercise interventions can be similarly applied to ICM and NICM patients regarding cardiac dimensions, systolic function, and exercise capacity.
• Findings support guideline recommendations for exercise in HFrEF without specific differentiation by etiology.