Electrical synchronization achieved by multipoint pacing combined with dynamic atrioventricular delay.
O'Donnell D., Wisnoskey B., Badie N., Odgers L., Smart T., Ord M., Lin T., Mangual JO., Cranke G., McSpadden LC., Ryu K., Bianchi V., D'Onofrio A., Pappone C., Calò L., Chow A., Betts TR., Thibault B., Varma N.
PURPOSE: Multipoint pacing (MPP) improves left ventricular (LV) electrical synchrony in cardiac resynchronization therapy (CRT). SyncAV automatically adjusts atrioventricular delay (AVD) according to intrinsic AV intervals and may further improve synchrony. Their combination has not been assessed. The objective was to evaluate the improvement in electrical synchrony achieved by SyncAV combined with MPP in an international, multicenter study. METHODS: Patients with LBBB undergoing CRT implant with a quadripolar lead (Abbott Quartet™) were prospectively enrolled. QRS duration (QRSd) was measured by blinded observers from 12-lead ECG during: intrinsic conduction, BiV pacing (conventional biventricular pacing, nominal static AVD), MPP (2 LV cathodes maximally spaced, nominal static AVD), BiV + SyncAV, and MPP + SyncAV. All SyncAV offsets were individualized for each patient to yield the narrowest QRSd during BiV pacing. QRSd changes were compared by ANOVA and post hoc Tukey-Kramer tests. RESULTS: One hundred and three patients were enrolled (65.7 ± 12.1 years, 67% male, 37% ischemic, EF 26.4 ± 6.5%, PR 190.3 ± 39.1 ms). Relative to intrinsic conduction (QRSd of 165 ± 16 ms), BiV reduced QRSd by 11.9% to 145 ± 18 ms (P