2.2 Participants recruitment
Consecutive patients who met the inclusion criteria were enrolled
between February 9, 2018 and October 16, 2020. The inclusion criteria
should meet the following: (1) an ECG showed a morphology of typical
complete RBBB (cRBBB). The diagnostic criteria of cRBBB is as following
: the QRS duration >0.12 sec, rSR’ or RR’ pattern in leads V1 and/or
V2, wide and slurred S wave in leads V6 and I (S>R duration or S wave
duration ≥ 0.06 sec) 6. (2) patients were indicated
for pacing therapy, (3) the LBB or LBB area was captured. Patients with
any one of the following conditions were excluded: (1) incomplete RBBB
(iRBBB), defined as the QRS duration in 0.10-0.12 sec and rsr’ pattern
in leads V1 and/or V2 6. (2) right ventricular septal
pacing (RVSP), (3) left bundle branch block (LBBB), including complete
LBBB, incomplete LBBB, left anterior fascicular block (LAFB), and left
posterior fascicular block (LPFB), (4) patients declining
guideline-indicated pacing therapy. The study was approved by the Ethics
Committee of Xiamen Cardiovascular Hospital, Xiamen University, and the
informed consent of each patient was obtained. The study was conducted
in accordance with the principles of the Declaration of Helsinki.