Fragmented QRS Complex And Nonresponse To Cardiac Resynchronization Therapy: A Meta-analysis

Objective:To assess whether fragmented QRS(f QRS)is an predictor of nonresponse to cardiac resynchronization therapy(CRT)in patients with heart failure.Methods:2investigators independently performed a comprehensive search on topics that assesses f QRS and its association with nonresponse to CRT and remodeling up until May 2022.meta-analyses were performed with Rev Man 5.4 and STATA/MP 14,and publication bias analyses and Sensitivity analysis were performed on the findings.Results:In a total of 6studies,three cohort studies and three case-control studies,with no statistically significant heterogeneity among the included studies.the results of the meta-analysis showed that the presence of f QRS is related to non-response to CRT(OR=1.58,95%CI,1.27～1.95,P<0.001).In addition,the results of subgroup analysis showed that the presence of f QRS also associated with Left ventricular end systolic volume(LVESV)and Left ventricular end diastolic volume(LVEDV)reduction after CRT,and the pooled effect amounts were(MD=23.24,95%CI,6.88～39.60,P=0.005,I~2=0%)and(MD=20.60,95%CI,2.75～38.46,P=0.02,I~2=0%)respectively.The results in the meta-analysis of the improvement in left ventricular ejection fraction(LVEF)after CRT implantation by the presence of f QRS did not show statistical significance,which was considered to be related to small sample size.Conclusions:Fragmented QRS is associated with nonresponse to cardiac resynchronization therapy and ventricular remodeling after CRT.