Table 1.

Baseline characteristics of the involved studies.

Study	Design	Center	CRT implantation criteria	Indications for AVJA	Follow up	NOS
Dong, 2010 [28]	Prospective cohort	Single-center	•HF symptoms despite optimal medical therapy •LVEF <35% •QRS duration ≥120 ms	Poor rate control	•274 (193 - 427) days in CRT + AVJA group •222 (111 -501) days in CRT group	8
Eisen, 2013 [29]	Retrospective cohort	Single-center	NA	NA	2 years	9
Ferreira, 2008 [30]	Retrospective cohort	Single-center	•Symptomatic HF (NYHA functional class II - IV) •Severe LV systolic dysfunction (LVEF ≤35%) •QRS duration >120 ms	NA	29 ± 18 months	8
Gasparini, 2006 [31]	Prospective cohort	Multicenter	•LVEF ≤35% •Ventricular conduction delay (QRS duration ≥120 ms) •NYHA functional class ≥II despite optimal drug therapy, including β-blockers, ACEIs or ARBs, diuretics, and spironolactone.	Biventricular pacing ≤85%	48 months	8
Gasparini, 2008 [32]	Prospective cohort	Multicenter	NA	Biventricular pacing ≤85%	34 (10 - 40) months	7
Gasparini, 2013 [33]	Prospective cohort	Multicenter	•Systolic HF in NYHA functional class III or ambulatory IV (or II in the case of a recent HF hospitalization) •LVEF ≤35% •QRS ≥120 ms •Maximum tolerated pharmacologic therapy with ACEIs or ARBs, β-blockers, diuretics, and spironolactone for at least 2 months.	Clinical improvement and/or adequate biventricular pacing percentage did not occur with rate slowing drugs within 3 months	37 (14 - 58) months	7
Gasparini, 2018 [34]	Prospective cohort	Multicenter	•Systolic HF in NYHA functional class III or ambulatory IV (or II in the case of recent HF hospitalization) •LVEF ≤35% •QRS ≥120 ms •Maximum tolerated pharmacological therapy and had at least 3-month follow-up.	Adequate biventricular pacing percentage (>95%) did not occur with rate-slowing drugs within 3 months	18 (12–18) months	8
Himmel, 2012 [35]	Prospective cohort	Single-center	•Drug-refractory HF (NYHA functional class III - IV), LVEF ≤35% •QRS duration ≥120 ms •LBBB morphology	Biventricular pacing ≤80%	12 ± 3 months	7
Jędrzejczyk-Patej, 2014 [36]	Prospective cohort	Single-center	•Refractory symptomatic HF (NYHA functional class III - IV) •LVEF ≤35% •QRS duration >120 ms	Biventricular pacing <95%	6 months	7
Molhoek, 2004 [37]	Prospective cohort	Single-center	•Drug-refractory HF (NYHA functional class III - IV) •LVEF <35% •QRS duration >120 ms or >200 ms for a paced QRS •LBBB morphology	NA	6 months	7
Schütte, 2009 [38]	Retrospective cohort	Single-center	•Drug-refractory HF (NYHA functional class III - IV) •LVEF <35% •QRS duration >120 ms •LBBB morphology	Biventricular pacing <90%	11 ± 0.34 months	7
Tolosana, 2008 [39]	Retrospective cohort	Multicenter	•Symptomatic HF (NYHA functional class ≥ III) despite optimal drug therapy, with LVEF ≤35%, and QRS duration >120 ms. OR •Symptomatic HF (NYHA functional class ≥II) with LVEF ≤35% who received a defibrillator or pacemaker and needed permanent pacing regardless of QRS duration.	Poor rate control despite negative chronotropic therapy	12 months	8
Tolosana, 2012 [40]	Prospective cohort	Multicenter	•Symptomatic HF (NYHA functional class ≥ III) despite optimal drug therapy, with LVEF ≤35%, and QRS duration >120 ms. OR •Symptomatic HF with LVEF ≤35% who received a pacemaker or defibrillator and were in NYHA functional class ≥II, regardless of QRS duration.	Biventricular pacing ≤85%	12 months	9
Tolosana, 2013 [41]	Prospective cohort	Single-center	•Symptomatic HF (NYHA functional class ≥III) despite optimal drug therapy, as well as LVEF ≤35% and QRS duration >120 ms. OR •Symptomatic HF with LVEF ≤35% who received a device, required continuous ventricular pacing due to severe bradycardia, and were in functional class ≥II were also included regardless of QRS duration.	Poor rate control	30 (13 - 51) months	8

AVJA = atrioventricular junction ablation; CRT = cardiac resynchronization therapy; HF = heart failure; LBBB = left bundle branch block; LV = left ventricle; LVEF = left ventricular ejection fraction; NA = not available; NOS = Newcastle-Ottawa scale; NYHA = New York Heart Association.