3.1 Study characteristics
Figure 1 shows the results of the search and selection process. Thirteen studies including 618 patients were included in these meta-analyses. The average age of the patients was 69.4 years and 299 of patients were male(48.3%). The overall successful rate of LBBAP was 92% (569/618). (Table1)
3.2.1 QRS duration at baseline and implantation
For patients with QRS duration<120ms, no significant difference was observed between baseline and paced QRS duration (107.3± 24.8ms vs 115.3 ±10.9 ms, P = 0.28 I2 = 92%,Figure 2A). For patients with QRS duration>120ms, the paced QRS duration was markedly decreased from 140.2 ± 34.2ms at baseline to 133.1 ± 16.7ms after LBBAP (P =0.02, I2 = 92%, Figure 2B), representing a mean narrowing of QRS duration.