Association between electrocardiographic QRS transition zone and mortality from all causes and cardiovascular diseases: A systematic review and meta-analysis

•Precordial QRS transition zone consists of CWR, CCWR and NR.•CWR was positively associated with a higher risk of all-cause and CVD mortality compared with NR.•CCWR was negatively associated with the risk of all-cause mortality and no significant association with CVD mortality.•QRS transition zone carries important prognostic value, more attention should be paid in clinical practice.