Primary outcome: all-cause mortality in all patients
The pooled aHR of studies suggested a lower all-cause mortality risk in patients receiving CRT-D compared with those receiving CRT-P (HR: 0.79, 95%CI: 0.72-0.88, I2=40.5%, P<0.0001) (Figure 2). Funnel plots for primary outcome was a little bit of asymmetric but both Egger’s test and Begg’s test did not indicate a significant bias (P=0.084). However, repeated analysis using HR of propensity matching cohort revealed that there was no significant difference in all-cause mortality between CRT-D and CRT-P (HR: 0.90, 95%CI: 0.68-1.18, I2=43.4%, P=0.438) (Figure 3). Further, we conducted a sensitivity analysis to demonstrate the robustness of our conclusion by removing one study at a time.