Ablation scar at the His bundle predicted persistent CAVB requiring pacemaker after ASA for HOCM with adjusted OR 7.1 (95%CI 1.7–29.9, p=0.008).
Does the presence of His-bundle area ablation scar on delayed enhancement CT predict persistent complete atrioventricular block in HOCM patients following alcohol septal ablation?
Delayed enhancement CT visualization of ablation scar at the His-bundle level strongly predicts the need for permanent pacemaker implantation due to persistent complete AV block following alcohol septal ablation for HOCM.
Absolute Event Rate: 0% vs 0%
Abstract Backgrounds Alcohol septal ablation (ASA) for hypertrophic obstructive cardiomyopathy (HOCM) carries a risk for procedural complete atrioventricular block (CAVB). However, the optimal timing for pacemaker implantation remains controversial. Delayed enhancement computed tomography (CT) visualizes the ablation scar, yet its relationship with CAVB remains unclear. Purpose We aimed to assess the utility of CT-based scar evaluation in predicting persistent CAVB following ASA for HOCM. Methods We analyzed ASA-induced scar using delayed enhancement CT. Patients with pure mid-cavity obstruction or prior implantable electric device were excluded. Post-CT was performed within 14 days. Scars were categorized by location: His-bundle ablation (HBA) was defined as basal septal scar near the membranous septum, evaluated on 4-chamber CT images. Right bundle branch ablation (RBA) was defined as right-sided anteroseptal scar at the septomaginal trabecula, assessed on short-axis CT images. Left ventricular edge ablation (LVEA) was defined as proximal LV septal scar forming part of the left ventricular outflow tract, evaluated on the 3-chamber CT images. Persistent CAVB was defined as a ventricular pacing rate 1% at 30 days. Logistic regression models adjusted for preexisting left bundle branch block (LBBB) and ethanol dose assessed the impact of HBA, RBA and LVEA. A p-value 0.05 was considered significant. Results Among 182 HOCM patients who underwent ASA, 56 (30.8%) developed CAVB during hospitalization, and 21 (11.5%) received pacemaker implantation. At 30 days, 9 (4.9%) had persistent CAVB, while other 12 (6.6%) recovered with a pacing rate 1%. HBA, RBA, and LVEA were observed in 30 (16.5%),165 (90.7%), and 113 (62.1%) patients, respectively. HBA was significantly associated with permanent CAVB (OR 6.3, 95%CI 1.8 – 22.2, p = 0.001), while RBA and LVEA were not significantly associated (RBA: 2.8, 95%CI 0.74 = 10.4, p = 0.075; LVEA: OR 2.1, 95%CI 0.5 – 10.0, p = 0.32). Among 9 patients with persistent CAVB, 5 had HBA, 3 had preexisting LBBB, and 1 recovered within 2 months post-ASA. HBA was independently associated with persistent CAVB (adjusted OR 7.1, 95%CI 1.7 – 29.9, p = 0.008). During follow-up, 3 additional patients underwent pacemaker implantation after surgical myectomy for residual LV obstruction after ASA. Conclusions Ablation scar at the His bundle level was a strong predictor of persistent CAVB requiring pacemaker implantation. CT-based scar evaluation may help in risk stratification for post-procedural conduction disturbances.Ablation Scar
Kawai et al. (Sat,) reported a other. Ablation scar at the His bundle predicted persistent CAVB requiring pacemaker after ASA for HOCM with adjusted OR 7.1 (95%CI 1.7–29.9, p=0.008).