Atrioventricular dyssynchrony from empiric device settings is common in cardiac resynchronization therapy and...

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Devices

Background:

• Echocardiographic atrioventricular (AV) optimization post-cardiac resynchronization therapy (CRT) is infrequently performed due to time constraints and proprietary algorithms.
• The clinical utility of optimizing mitral inflow velocities after CRT remains uncertain.
• Investigating post-implantation left ventricular (LV) inflow patterns can reveal the incidence of AV dyssynchrony in patients with empirically set devices.

Purpose of the Study:

• To investigate post-implantation LV inflow patterns in patients receiving CRT with empiric device settings.
• To determine the incidence of AV dyssynchrony in this patient population.
• To assess the impact of AV dyssynchrony on LV remodeling and clinical outcomes.

Main Methods:

• Retrospective analysis of 48 patients undergoing CRT with empiric device settings.
• Patients were grouped based on post-implantation LV filling patterns (AV dyssynchrony vs. no AV dyssynchrony).
• Comparison of baseline characteristics and echocardiographic measurements with post-implantation findings at a median of 6.3 months.

Main Results:

• Twenty-four patients (50%) exhibited AV dyssynchrony post-CRT.
• Patients with AV dyssynchrony showed less LV reverse remodeling compared to those without.
• No significant differences were observed in LV outflow tract velocity time integral, stroke volume, LV ejection fraction, new-onset atrial fibrillation, heart failure readmissions, or mortality between groups.

Conclusions:

• Up to 50% of patients with empiric CRT settings experience AV dyssynchrony at 6 months, despite AV optimization algorithms.
• AV dyssynchrony is common and modifiable, suggesting a need for strategic Doppler echocardiography-guided AV optimization.
• This approach is particularly important for nonresponders with fused or truncated LV filling patterns.