Impaired cardiac mechanical synchrony revealed with increased myocardial work in women with advanced age

Area of Science:

• Cardiovascular Physiology
• Cardiac Mechanics
• Echocardiography

Background:

• The influence of sex and aging on myocardial synchrony under stress is not well understood.
• This study investigated sex- and age-related differences in cardiac mechanical synchrony during hemodynamic stress.

Purpose of the Study:

• To determine how sex and age affect cardiac mechanical synchrony during controlled hemodynamic stress.
• To assess left ventricular mechanical dyssynchrony (LVMD) in young and older men and women during exercise.

Main Methods:

• Transthoracic speckle-tracking echocardiography and central hemodynamics were measured at rest and during exercise.
• Left ventricular mechanical dyssynchrony (LVMD) was quantified using time to peak standard deviation (TPSD) of longitudinal and transverse strain and strain rates (LSR, TSR).
• Participants included healthy young (<45 years) and older (≥45 years) women and men matched for physical activity and exercise capacity.

Main Results:

• No significant differences in resting LVMD or hemodynamic parameters were observed between sexes or age groups at rest or during exercise at matched relative intensities.
• A significant age effect was found for transverse LVMD (P-for-age ≤ 0.011).
• Older women exhibited significantly increased transverse strain rate TPSD (≥42%) during all exercise intensities compared to younger women (P ≤ 0.005).

Conclusions:

• Advanced age is associated with impaired cardiac mechanical synchrony in the transverse axis of the left ventricle during elevated hemodynamic stress, particularly in women.
• Sex alone was not a primary determinant of LVMD under these conditions.