Early Left Ventricular Mechanical Dyssynchrony Predicts Left Atrial Dysfunction Following Right Ventricular Pacing

Area of Science:

• Cardiology
• Echocardiography
• Cardiac Mechanics

Background:

• Left atrial reservoir strain (LASr) indicates left atrial (LA) mechanical function.
• Impaired LASr may precede heart failure with preserved ejection fraction (HFpEF) in patients with conventional right ventricular (RV) pacing.
• Early detection of LA dysfunction is crucial in these patients.

Purpose of the Study:

• To identify early predictors of impaired LASr at 12 months after conventional RV pacing.
• To investigate the relationship between left ventricular (LV) mechanical dispersion (LVMD) and subsequent LA dysfunction.
• To assess the role of LVMD in predicting adverse atrial remodeling.

Main Methods:

• Prospective enrollment of 52 patients undergoing conventional RV pacing.
• Transthoracic echocardiography (TTE) performed at baseline, 3, and 12 months.
• Assessment of LVMD, LV global longitudinal strain (LVGLS), diastolic function, and LA strain parameters.
• Stratification of patients based on 12-month LASr (<25% defined impaired LA mechanics).

Main Results:

• 36.5% of patients developed impaired LA mechanics at 12 months.
• At 3 months, impaired LA mechanics group showed higher LVMD (p < 0.001), reduced LVGLS (p = 0.03), and higher E/e' (p = 0.04).
• 3-month LVMD independently predicted impaired LASr at 12 months (OR 2.04, p = 0.01) with high discriminatory performance (AUC 0.84).

Conclusions:

• Early LVMD precedes overt atrial dysfunction in patients with conventional RV pacing.
• LVMD is an independent predictor of subsequent LA mechanical impairment.
• LVMD may identify patients at risk for adverse atrial remodeling and potential heart failure development.