Echocardiographic mapping of left ventricular resynchronization during cardiac resynchronization therapy procedures

Area of Science:

• Cardiology
• Medical Devices
• Heart Failure Management

Background:

• Cardiac resynchronization therapy (CRT) is a key treatment for heart failure with dyssynchrony.
• Effective CRT relies on optimal biventricular pacing (BVP) for left ventricular (LV) resynchronization.

Purpose of the Study:

• To assess acute LV resynchronization with BVP at various LV pacing sites.
• To evaluate the feasibility of using transthoracic echocardiography (TTE) during CRT implantation to guide LV lead placement.

Main Methods:

• Fourteen heart failure patients underwent CRT implantation.
• Tissue Doppler imaging (TDI) assessed septal-lateral delay (SLD) during BVP at multiple LV sites.
• Synchronicity gain index (Sg) quantified resynchronization improvement.

Main Results:

• 58% of tested LV sites showed positive resynchronization (R+).
• Posterior/lateral LV sites were more likely to achieve R+ than anterior sites (66% vs. 36%).
• Empirical LV lead implantation achieved R+ in only 50% of patients.

Conclusions:

• LV lead location significantly impacts acute resynchronization during CRT.
• TTE is a feasible tool to identify optimal LV sites for positive resynchronization during implantation.
• Current empirical LV lead placement has limited concordance with optimal resynchronization sites.