Distinct hemodynamic implications of junctional rhythm versus sinus rhythm on cardiac reverse remodeling after the Maze procedure.

Abstract

Background: Surgical success after the Maze procedure is conventionally defined as "freedom from atrial fibrillation (AF)," often grouping junctional rhythm (JR) with normal sinus rhythm (NSR). However, the specific hemodynamic impact of JR remains poorly understood. This study investigated whether JR truly represents a successful outcome compared to NSR and AF.

Methods: We retrospectively analyzed patients undergoing the Maze procedure (2012-2024). After designating the first postoperative month as a blanking period for rhythm instability, we included only patients maintaining a consistent rhythm without crossover from 1 to 12 months postoperatively: AF (n = 71), NSR (n = 213), and JR (n = 35). Outcomes included cardiac reverse remodeling-assessed by left atrial contractile strain (LASct) and chamber dimensions-and permanent pacemaker (PPM) implantation.

Results: In the IPTW-adjusted cohort, the NSR group achieved significant cardiac reverse remodeling, characterized by improved LVEF (58.5%), reduced LA volume index (75.1 mL/m²), and notable recovery of LASct. In stark contrast, the JR group failed to show any reverse remodeling or mechanical recovery, exhibiting hemodynamic stagnation indistinguishable from the AF group. Consequently, no significant difference in cardiac function was observed between the JR and AF groups. Furthermore, the JR group faced a drastically elevated risk of PPM implantation compared to both the NSR and AF groups (P < 0.001).

Conclusions: JR is not a benign alternative to sinus rhythm; it mimics AF in preventing cardiac reverse remodeling and carries a high risk of pacemaker dependency. Therefore, JR should be clinically differentiated from NSR and recognized as a suboptimal hemodynamic outcome similar to AF.