Real-time 3D echo in patient selection for cardiac resynchronization therapy.

Area of Science:

• Cardiology
• Medical Imaging
• Echocardiography

Background:

• Left ventricular mechanical dyssynchrony (LVMD) assessment is crucial for optimizing cardiac resynchronization therapy (CRT) patient selection.
• Three-dimensional (3D) echocardiography offers reproducible quantification of LV structure, function, and LVMD.

Purpose of the Study:

• To investigate the utility of 3D echo in quantifying LVMD.
• To assess interhospital agreement for LVMD measurements.
• To evaluate the impact of LVMD quantification on patient selection for CRT.

Main Methods:

• 187 patients from two institutions were studied using 3D echo.
• Quantification of LV volumes, ejection fraction (LVEF), and systolic dyssynchrony index (SDI) was performed.
• Interhospital agreement was analyzed using shared cases; CRT outcomes were correlated with SDI and QRS duration.

Main Results:

• Excellent interhospital agreement was observed for 3D echo-derived parameters (LV volumes, LVEF, SDI).
• SDI demonstrated high predictive value for CRT response (NYHA class, LVEF, LV end-systolic volume), outperforming QRS duration.
• A SDI cutoff of 10.4% showed the highest accuracy for predicting CRT improvement.

Conclusions:

• 3D echo provides reproducible LVMD quantification across different centers.
• SDI is a strong predictor of CRT response and can identify suitable patients regardless of QRS characteristics.