Supplementary Material
Figure S1. Quadripolar left ventricular lead (Quartet™,
model 1458Q, Abbott). We first chose one of the two distal electrodes
(D1 or M2). Subsequently, we chose one of the two proximal electrodes
(M3 or P4), prioritizing the maximum distance between LV1 and LV2: D1/P4
> D1/M3 or M2/P4.
Figure S2 Description of the fusion-optimized atrioventricular
(AV) interval method. During atrial sensing, the AV interval was
progressively shortened by 20 ms during left ventricular (LV) pacing
alone, from intrinsic conduction with a long AV interval (second
left ) to only LV activation with a short AV interval (right ).
The AV interval that provided the narrowest QRS was selected and
considered the fusion-optimized AV interval (AV FOI). QRSd, QRS
duration.
Figure S3 Evaluation of cardiac asynchrony at several levels
using echocardiography. A Left intraventricular: septal flash
on M-mode imaging (yellow arrows ). B Atrioventricular:
diastolic filling ratio (diastolic filling time [DFT]/RR interval
duration). C, D Interventricular: the difference between the
left (D, orange ) and right (C, blue ) ventricular
pre-ejection times using pulsed-wave Doppler.