Left ventricular structure and function by echocardiography in ultraendurance athletes

Area of Science:

• Cardiology
• Sports Medicine
• Exercise Physiology

Background:

• Ultraendurance exercise training is associated with significant cardiovascular adaptations.
• Understanding the specific structural and functional changes in the left ventricle (LV) is crucial for differentiating physiological adaptations from pathological conditions.

Purpose of the Study:

• To investigate the structural and functional changes in the left ventricle (LV) of triathletes undergoing intensive ultraendurance training.
• To compare cardiac adaptations in elite athletes with those in a control group of normal subjects.

Main Methods:

• Utilized M-mode echocardiograms and Doppler recordings of LV inflow velocity.
• Studied 26 triathletes with over 2 years of training (20-40 hours/week) and 17 healthy control subjects.
• Assessed LV dimensions, wall thickness, mass, systolic function, and diastolic function.

Main Results:

• Triathletes exhibited increased LV wall thickness, relative wall thickness, and LV mass compared to controls.
• No significant differences were observed in LV systolic function or early diastolic function between groups.
• A slight increase in the Doppler-derived ratio of early-to-late LV inflow velocities was noted in triathletes.

Conclusions:

• Ultraendurance training induces a physiological pattern of left ventricular (LV) hypertrophy, consistent with moderate pressure overload.
• This cardiac remodeling is proportional to the hemodynamic load experienced during prolonged exercise.
• Early diastolic function remains normal in the athlete's heart, differentiating it from hypertensive cardiac hypertrophy.