Subgroup analyses
We performed several subgroup analyses as mentioned below. When restricted the research center to non-European country, we found that CRT-D showed a trend of mortality benefits in all-cause mortality, which did not reach the statistically significant (HR: 0.90, 95%CI: 0.80-1.01, I2=0%, P=0.085) (Supplementary Figure 3). For CRT-D in primary prevention, the pooled HR suggested that additional ICD therapy did not reduce all-cause mortality (HR: 0.92, 95%CI: 0.74-1.14, I2=0%, P=0.444) (Supplementary Figure 4). With long-term follow-up (≥5 years), CRT-D also did not show advantages in reducing all-cause mortality compared to CRT-P (HR: 0.78, 95%CI: 0.46-1.34, I2=76.4%, P=0.373) (Supplementary Figure 5).