Conduction disorders after perimembranous ventricular septal defect closure: continuous versus interrupted suturing techniques

OBJECTIVES: The aim of this study was to investigate postoperative conduction disorder differences between continuous and interrupted suturing techniques for the closure of perimembranous outlet-type ventricular septal defects (VSDs) in both tetralogy of Fallot (ToF) and isolated VSD cases. METHODS: Patients aged 4 years or younger who underwent VSD closure for ToF (n = 112) or isolated perimembranous outlet-type VSD (n = 73) from April 2010 to December 2018 at 3 centres were reviewed. Patients either received continuous suturing for ToF (C-ToF, n = 58) or isolated VSD (C-VSD, n = 50), or interrupted suturing for ToF (I-ToF, n = 54) or isolated VSD (I-VSD, n = 23). Cohorts did not differ in preoperative characteristics. Postoperative conduction disorder differences upon discharge and postoperative year 1 (POY1) were evaluated by electrocardiography. RESULTS: The C-ToF group showed significantly shorter PQ intervals (124.0 vs 133.5 ms; P = 0.042 upon discharge, 125.3 vs 133.5 ms; P = 0.045 at POY1) and QRS durations (98.0 vs 106.2 ms; P = 0.031 upon discharge, 97.3 vs 102.5 ms; P = 0.040 at POY1) than the I-ToF group. Right bundle branch block incidence was significantly lower in the C-ToF versus I-ToF groups (56.8 vs 75.9; P = 0.045 upon discharge, 56.8 vs 75.9; P = 0.045 at POY1). Heart rates were significantly lower in the C-ToF versus I-ToF groups at POY1 (109.2 vs 119.3 bpm; P < 0.001). No parameters significantly differed between C-VSD and I-VSD groups. Multivariable analyses confirmed the group (C-ToF versus I-ToF) as a significant covariate in postoperative heart rate, PQ interval, QRS duration and right bundle branch block outcomes at POY1 (P = 0.013, 0.027, 0.013 and 0.014, respectively). CONCLUSIONS: A continuous suturing technique for the closure of outlet-type VSD in ToF could reduce the incidence of postoperative right bundle branch block, shorten the PQ interval and lower heart rate.

Automated summary

The use of continuous suturing technique for the closure of outlet-type VSD in ToF can reduce the incidence of postoperative right bundle branch block, shorten the PQ interval, and lower heart rate.