Mechanical Dyssynchrony Combined with Septal Scarring Reliably Identifies Responders to Cardiac Resynchronization...

Area of Science:

• Cardiology
• Medical Imaging
• Heart Failure Treatment

Background:

• Mechanical dyssynchrony on echocardiography predicts positive outcomes after cardiac resynchronization therapy (CRT).
• Myocardial scar, however, can diminish the effectiveness of CRT.
• Identifying CRT responders is crucial for optimizing treatment efficacy.

Purpose of the Study:

• To evaluate the combined predictive power of mechanical dyssynchrony and myocardial scarring markers for CRT response.
• To compare this combined assessment with traditional predictors like QRS duration and morphology.
• To assess the impact of combined markers on long-term mortality after CRT.

Main Methods:

• A prospective multicentre study involving 170 CRT recipients.
• Echocardiographic assessment of mechanical dyssynchrony markers: septal flash, apical rocking, systolic stretch index, and lateral-to-septal work difference.
• Myocardial scarring quantification via cardiac magnetic resonance imaging or exclusion via coronary angiogram and clinical history.

Main Results:

• Combined assessment of mechanical dyssynchrony and septal scarring showed high predictive power (AUCs 0.81-0.86) for CRT response, outperforming mechanical dyssynchrony alone.
• Traditional predictors (QRS morphology, duration, LV ejection fraction) were not superior.
• The combined assessment also significantly predicted all-cause mortality.

Conclusions:

• The combined assessment of echocardiographic mechanical dyssynchrony and myocardial scarring is a powerful tool for identifying CRT responders.
• Both visual and quantitative imaging markers demonstrated high feasibility and similar predictive results.
• This integrated imaging approach is valuable for CRT candidate selection in routine clinical practice.