Clinical Outcomes After Ablation of the AV Junction in Patients With Atrial Fibrillation: Impact of Cardiac Resynchronization Therapy

Abstract

Background: Patients with atrial fibrillation (AF) often undergo AV junction ablation (AVJA) and pacemaker implantation. Right ventricular (RV) pacing contributes to increased risk of heart failure (HF), which may be mitigated by biventricular pacing. We sought to determine the impact of AVJA concurrent with RV versus biventricular pacemaker implantation on AF and HF hospitalizations.

Methods and results: The MarketScan Commercial and Medicare Supplemental claims database was used to select 18- to 100-year-old patients with AF with pacemaker implantation. Patients were divided into those with an RV and a biventricular pacemaker and further into those who did (AVJA⁺) or did not undergo concurrent ablation. Separately, the AVJA⁺ group was divided into those receiving RV versus biventricular pacemakers. AF and HF hospitalization rates were compared between groups after matching on demographics, comorbidities, and baseline hospitalization rates. The study included 24 361 patients, with RV (n=23 377) or biventricular (n=984) pacemakers; 1611 patients underwent AVJA. AVJA⁺ was associated with reduced AF hospitalization risk (RV hazard ratio [HR], 0.31; P<0.001; biventricular HR, 0.20; P=0.003) compared with no AVJA. However, HF hospitalization risk was increased for RV (HR, 1.63; P=0.001), but not biventricular (HR, 0.98; P=0.942), pacemakers. In AVJA⁺ patients, biventricular pacing was associated with reduced risk of HF hospitalization versus RV pacing (HR, 0.62; P=0.017).

Conclusions: In a large cohort of patients with AF, AVJA⁺ significantly reduced AF hospitalizations, irrespective of whether an RV or a biventricular pacemaker was implanted. However, AVJA was associated with a marked HF hospitalization increase in patients with an RV pacemaker, which was ameliorated with biventricular pacing.

Keywords: ablation; atrial fibrillation; biventricular pacing; heart failure; pacemaker.

Figure 1

Cohort diagram. Schematic of patients included in the study cohort, including those with and without AV junction ablation (AVJA ⁺ and AVJA ⁻, respectively) on the same day as pacemaker implantation. AF indicates atrial fibrillation; and RV, right ventricular (single or dual chamber). BiV indicates biventricular; PM, pacemaker.

Figure 2

Risk of hospitalization after pacemaker implantation. Kaplan‐Meier survival curves for risk of atrial fibrillation (A) or heart failure hospitalization (B) in matched patients with vs without AV junction ablation (AVJA ⁺ and AVJA ⁻, respectively) at pacemaker implantation. CI indicates confidence interval; HR, hazard ratio; and RV, right ventricular (single or dual chamber). BiV indicates biventricular; PM, pacemaker.

Figure 3

Risk of heart failure hospitalization after AV junction ablation (AVJA). Kaplan‐Meier survival curve for risk of heart failure hospitalization in matched patients implanted with a biventricular vs a right ventricular (RV; single or dual chamber) pacemaker at AVJA. CI indicates confidence interval; and HR, hazard ratio.

Figure 4

Forest plot showing adjusted risk of heart failure (HF) hospitalization after AV junction ablation (AVJA). Propensity score–adjusted risk of HF hospitalization in patients implanted with a biventricular vs a right ventricular (RV; single or dual chamber) pacemaker at AVJA. CAD indicates coronary artery disease; HR, hazard ratio; and VT/VF, ventricular tachycardia/ventricular fibrillation. BiV indicates biventricular; PM, pacemaker.

Figure 5

Bar plot showing the distribution of cumulative heart failure hospitalizations (HFHs) during a median 2.08 years of follow‐up after AV junction ablation (AVJA). After AVJA, the cumulative number of HFHs in matched biventricular and right ventricular (RV; single or dual chamber) pacemaker cohorts. BiV indicates biventricular; PM, pacemaker.