Table 1. Baseline and procedural characteristics of included studies (Sweeney et al., 2003).

No	Study	Year	Study design	Type	Country	Intervention	Sample size (n)	The diagnosis of PCIM
1	Vijayaraman et al. (2019a)	2019	Single-arm	Retrospective	USA	HBP	57	A 10% decrease in left ventricular ejection fraction (LVEF) from baseline resulting in LVEF <50% among patients experiencing >20% RV pacing without an alternative cause of cardiomyopathy.
2	Li et al. (2021)	2021	Single-arm	Perspective	China	LBBP	10	The baseline of the left ventricular ejection fraction (LVEF) is no less than 50%, and the LVEF during follow-up is no more than 40%. The baseline of the LVEF is less than 50%, and the absolute value of the LVEF is reduced by more than 10% during follow-up. The total value of the LVEF is reduced by 10% regardless of the LVEF baseline.
3	Shan et al. (2018)	2018	Single-arm	Perspective	China	HBP	11	Pacing at least 20% of the time despite device reprogramming to minimize ventricular pacing
4	Qian et al. (2021)	2021	Control-conhort	Perspective	China	LBBP	13	A ≥10% decrease in left ventricular ejection fraction (LVEF) after RV pacing (ventricular pacing percentage over 20%) with resultant LVEF ≤50% without an alternative cause of cardiomyopathy, and with symptoms of heart failure.
5	Yang et al. (2021)	2021	Single-arm	Perspective	China	HBP and LBBP	34 (29/5)	(1) Patients with prior RVP implantation (including DDD and VVI pacemaker.) and the percentage of RVP > 40%; (2) A LVEF of ≤40% caused by a new onset LVEF decrease of >10% from baseline, without other identifiable causes.
6	Ye et al. (2021)	2021	Single-arm	Retrospective	China	LBBP	19	(1) A >10% decrease in left ventricular ejection fraction (LVEF) after chronic RVP resulting in LVEF ≤ 50%. (2) The pacing percentage of RVP was >40%.
7	Rademakers et al. (2022)	2022	Single-arm	Perspective	The Netherlands	LBBP	20	Patients with RV pacing (ventricular pacing percentage over 70%), the value of the LVEF is reduced by at least 10%, resulting in LVEF <50%.