Relation of age to left ventricular function in clinically normal adults

Area of Science:

• Cardiology
• Gerontology
• Physiology

Background:

• The independent impact of aging on left ventricular (LV) function, separate from cardiovascular diseases, remains unclear.
• Understanding age-related cardiac changes is crucial for differentiating normal aging from pathological conditions.

Purpose of the Study:

• To investigate the influence of age on left ventricular (LV) function and arterial stiffness in clinically normal adults.
• To differentiate between age-related changes in endocardial versus midwall myocardial function.

Main Methods:

• Echocardiography and arterial pressure measurements were performed on 464 healthy adults (aged 16-88 years).
• LV dimensions, fractional shortening, stroke volume, cardiac output, and end-systolic stress were assessed.
• Afterload-corrected measures of LV function were calculated to control for changes in wall thickness and blood pressure.

Main Results:

• Cardiac index slightly decreased with age, while total peripheral resistance and arterial stiffness increased significantly.
• Endocardial shortening showed a slight age-related increase, but afterload-corrected midwall shortening demonstrated a slight decline.
• LV pump performance changes were associated with smaller LV chamber size and increased total peripheral resistance in older adults.

Conclusions:

• Advancing age is associated with a slight reduction in resting cardiac index and midwall myocardial function in healthy individuals.
• While endocardial function may not decline, age-related increases in arterial stiffness and changes in LV chamber size contribute to altered LV pump performance.
• These findings help distinguish normal age-related cardiovascular adaptations from disease processes.