Abstract 2933: Comparison of Bi-Ventricular Endocardial Vs. Epicardial Pacing Via the Coronary Sinus for Left Ventricular Synchronization
Background: The current approach for cardiac resynchronization therapy includes left ventricular free wall epicardial pacing. We sought to evaluate the impact of replacing left ventricular epicardial pacing with endocardial pacing to mimic normal electromechanical coupling patterns.
Methods: Left ventricular synchronization was evaluated by tissue Doppler imaging (TDI) and 2D strain (speckle tracking) in 4 heart failure mongreal dog model. Heart failure was induced by rapid RV apical pacing for 21 days. Pacing electrodes were placed in the RV septal (RVS), coronary sinus (CS) and LV endocardium (LVE). LV endocardial lead was placed via atrial transeptal approach and positioned under fluoroscopy in the posterolateral wall adjacent to the CS lead tip. The heart rate and AV delay were set constant in all experiments. Echo was performed at baseline and in each pacing configuration. Based on previous experiences we chose RV septal pacing when combined with CS or LV endocardial pacing.
Results: LVE was superior to CS pacing in restoring both radial (p = 0.01) and longitudinal (p < 0.055) LV contractions patterns (Figure⇓) as well as synchrony.
Conclusion: LVE appears as a promising approach for future LV synchronization and might be clinically applicable through a wireless approach.