QTc shortening effect of ganglionated plexi ablation.

BACKGROUND

In previous studies, patients undergoing ablation of ganglionated plexi (GPA) for vagally mediated bradyarrhythmias were noted to have shortening of their corrected QT interval (QTc).

AIMS: To compare the effects of GPA (group 1) to pulmonary vein isolation + GPA (group 2) on QTc.

MATERIAL AND

METHODS

We enrolled 39 patients, n = 25 in group 1 and n = 14 in group 2. QTc was calculated at baseline, at 24 h after ablation, and at 9-12 months in the follow-up. Recurrent syncope, asystole >2 s, and/or second- or third-degree AVB episodes were carefully documented as the primary outcome in group 1. Any atrial arrhythmia ≥30 seconds documented on 24-h Holter monitoring was defined as the primary outcome in group 2.

RESULTS

The mean follow-up time was 14.9 ± 4 months. Acute success was achieved in all cases. In whole cohort, a significant shortening on QTcBazett, QTcFramingham, QTcFredericia, and QTcHodges was observed [416 vs 398ms (p = .002), 411vs 378 ms (p < .001), 412 vs 379ms (p < .001), and 420 vs 383ms (p < .001), respectively]. In the linear mixed model analysis, the longitudinal reduction tendency in the QTc level was more pronounced in group 1. Event-free survival was detected in 90.7% (59/65) of cases.

DISCUSSION: Our results demonstrate a significant shortening of QTc in addition to high medium-term success rates after GPA. Pulmonary vein isolation + GPA was associated with lower QTc shortening effect which implies structural disease may change electrophysiological response to ablation. The most likely mechanism is the effect of GPA on the sympathetic system.