Introduction
Cardiac resynchronization therapy (CRT) with multipoint pacing (MPP) shortens the QRS duration1 and improves outcomes compared to single-point left ventricular (LV) pacing.2,3 However, MPP causes higher battery drain.4-6 On the other hand, electrocardiographic optimization using the fusion-optimized intervals (FOI) method also shortens the QRS duration7-9 and achieves greater LV reverse remodeling than nominal programming.10
The magnitude of QRS shortening is associated with clinical and prognostic improvements in patients with CRT11 and serves as a surrogate for the cardiac activation time. The activation time can be measured through electrocardiographic imaging (ECGI) using body surface potential mapping. Thus, ECGI yields a high-resolution single-beat ventricular activation map.12
The objective of the present study was to determine whether MPP could attain better resynchronization than single-point pacing (SPP) optimized by FOI.