Acute Changes on Left Atrial Function during Incremental Exercise in Patients with Heart Failure with Mildly Reduced...

Area of Science:

• Cardiology
• Exercise Physiology
• Cardiac Imaging

Background:

• Heart failure with mildly reduced ejection fraction (HFmrEF) affects cardiac function.
• Left atrial (LA) function's role in HFmrEF during exercise is not fully understood.
• Assessing acute changes in LA function during aerobic exercise is crucial for understanding HFmrEF pathophysiology.

Purpose of the Study:

• To evaluate acute alterations in left atrial (LA) function during incremental aerobic exercise.
• To compare LA function changes in patients with HFmrEF versus healthy subjects (HS).
• To investigate the contribution of LA function to stroke volume (SV) maintenance in HFmrEF during exercise.

Main Methods:

• Compared 20 HFmrEF patients with 10 age-matched HS.
• Subjects underwent stepwise exercise testing on a cycle ergometer.
• Echocardiography assessed LA function at rest, during submaximal exercise, peak exercise, and recovery.

Main Results:

• HFmrEF patients showed preserved peak atrial longitudinal strain (PALS) and conduit strain at peak exercise, unlike HS.
• Stroke volume (SV) remained constant in HFmrEF but decreased in HS at peak exercise.
• Heart rate and systolic blood pressure increased more in HS than in HFmrEF.

Conclusions:

• Patients with HFmrEF demonstrate effective left atrial (LA) reservoir function during incremental aerobic exercise.
• This enhanced LA function aids in maintaining stroke volume (SV) during physical exertion.
• Findings highlight the adaptive mechanisms in HFmrEF contributing to exercise capacity.