In the GANGLIA-AF study, published in Heart Rhythm, researchers hypothesized that ablating the ectopy–triggering ganglionated plexuses (ET-GP) of the intrinsic cardiac autonomic system may serve to reduce the incidence of atrial fibrillation (AF). The study’s lead author, Min-Young Kim, and colleagues found that GP ablation (GPA) without pulmonary vein isolation (PVI) did not reduce atrial arrhythmias more than PVI in patients with paroxysmal AF.
A total of 102 patients were enrolled into the randomized trial after receiving GPA or PVI and followed for 12 months, including 48-hour Holter monitors every three months. ET-GPs were mapped using high-frequency stimulation (HFS) during the atrial refractory period and ablated until they no longer function. As a follow–up, if cases of triggered AF became persistent, atrioventricular disassociating GPs (AVD-GP) were also ablated. The primary endpoint was documented ≥30 second atrial arrhythmia after a three-month blanking period.
Fifty-two patients underwent GPA and 50 underwent PVI. GPA patients had 89±26 HFS sites tested, identifying a median of 18.5 GPs (interquartile range [IQR], 16–21%). RF ablation procedure time for GPA patients was 22.9 ± 9.8mins versus 38 ± 14.4mins in PVI (p < 0.0001). GPA participants’ freedom from ≥30 second atrial arrhythmias at 12-month follow-up was 50%, comparted to 64% with PVI (log rank p = 0.09). ET-GP ablation without AVD-GP ablation achieved 58% (n = 22/38) freedom from the primary endpoint. There was a significantly higher reduction in AAD usage post-ablation after GPA versus PVI (55.5% vs. 36%; p = 0.05). Patients were referred for redo ablations in 31% (n = 16/52) after GPA and 24% (n = 12/50) after PVI (p = 0.53).
While the two techniques did not produce different results in terms of preventing arrhythmias, the authors did note that, “less RF ablation was delivered to achieve a higher reduction in anti-arrhythmic drug usage with GPA than PVI.”