Vectorcardiography-derived index allows a robust quantification of ventricular electrical synchrony.

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Imaging

Background:

• Altered muscle activation sequences are central to heart failure with reduced ejection fraction.
• Current cardiac resynchronization therapy (CRT) effectiveness is hampered by imprecise dyssynchrony quantification.

Purpose of the Study:

• To develop and validate a computational pipeline for assessing ventricular dyssynchrony from electrocardiograms (ECG).
• To establish a novel ventricular dyssynchrony index for improved patient selection and management in heart failure.

Main Methods:

• Vectorcardiogram reconstruction from patient ECGs to assess ventricular dyssynchrony.
• Defined a dyssynchrony index based on voltage and speed time integrals compared to healthy populations.
• Validated the pipeline in a 1914-patient cohort, including those with left bundle branch block (LBBB) and pacemakers (PM).

Main Results:

• The dyssynchrony index was lowest in healthy controls and highest in patients with LBBB or PM.
• A critical index value was identified to differentiate electrical dyssynchrony from synchrony.
• High dyssynchrony indexes correlated with echocardiographic measures of mechanical dyssynchrony in patients with PM or CRT devices.

Conclusions:

• The developed dyssynchrony index is a promising tool for evaluating ventricular activation.
• This index may improve patient selection for CRT, device configuration, and post-implantation optimization.
• Enhanced dyssynchrony assessment can lead to more effective CRT in heart failure patients.