High-intensity aerobic exercise improves diastolic function in coronary artery disease

Area of Science:

• Cardiology
• Exercise Physiology
• Echocardiography

Background:

• Stable coronary artery disease (CAD) affects left ventricular (LV) function.
• Exercise training is a cornerstone of cardiac rehabilitation for CAD patients.
• Optimizing exercise intensity for maximal benefit in LV function remains an area of research.

Purpose of the Study:

• To investigate the impact of different aerobic treadmill exercise intensities on LV function in stable CAD patients.
• To utilize Strain Rate Imaging and Tissue Doppler Imaging to assess LV diastolic and systolic function.

Main Methods:

• Seventeen patients with stable CAD were randomized into two groups: moderate-intensity (50-60% VO2peak) and high-intensity (80-90% VO2peak) exercise.
• Exercise training duration was 10 weeks.
• Left ventricular function was assessed using Strain Rate and Tissue Doppler Imaging.

Main Results:

• High-intensity exercise group showed a significantly greater increase in peak oxygen uptake (VO2peak) compared to the moderate-intensity group (17% vs. 8%, p=0.01).
• Mean LV early diastolic strain rate significantly increased in the high-intensity group, indicating improved diastolic relaxation.
• No significant changes were observed in systolic strain rate or mitral annular velocities in either group post-training.

Conclusions:

• Aerobic treadmill exercise, particularly at high intensity, enhances early diastolic relaxation in patients with stable CAD.
• LV early diastolic strain rate is a sensitive measure for detecting exercise-induced improvements in diastolic function.
• High-intensity exercise may offer superior benefits for diastolic function compared to moderate-intensity exercise in this population.