CE-452780-1 LEFT ATRIAL VOLUME IS THE STRONGEST PREDICTOR OF ATRIAL ARRHYTHMIA RECURRENCE AFTER PULMONARY VEIN ISOLATION ALONE IN PERSISTENT AF: A DECAAF II SUBSTUDY

Abstract

Left atrial volume (LAV) is a known predictor of atrial arrhythmia recurrence (AAR) after pulmonary vein isolation (PVI). We sought to assess the role of LAV in predicting AAR in pts with persistent atrial fibrillation (PrAF) undergoing PVI alone as the initial procedure. The DECAAF II Trial was a prospective randomized trial of pts with PrAF undergoing initial ablation. Baseline demographics and risk factors were collected for all pts, who also underwent late gadolinium enhanced magnetic resonance imaging for calculation of baseline LAV and atrial fibrosis. Of 408 pts in the control group (PVI alone), 47 were excluded predominantly due to receiving additional LA ablation. The remaining 361 pts constituted the study population. Pts provided single-lead home ECG strips once daily and during symptoms. The primary endpoint was single-procedure success, defined as freedom from AAR (AF, flutter or atrial tachycardia > 30 sec) following a 90-day blanking period through 365 days post-procedure. A receiver operating curve (ROC) was performed to identify the optimal LAV predicting success. A covariate adjusted Cox regression model was performed to identify independent predictors of outcome. At baseline, the mean pt age was 62±9 yrs, and 80% were male. Mean fibrosis was 19±8%, and median LAV was 129 cc (IQR: 104-154). ROC analysis identified LAV < 114 cc as the optimal cut-point. In the Cox model, LAV < 114 cc was the only significant predictor of procedural success (p=0.004) with a hazard ratio of 0.53 (95% CI 0.35-0.82,table). Pts with LAV < 114 cc had one year freedom from RAA of 73% (95% CI 65-81%) vs 53% (95% CI 47-60%) in pts with larger LAV (p=0.00043,log-rank,figure). Baseline LAV < 114 cc was present in 120/361 pts (33%). LAV is the strongest predictor of RAA in pts with PrAF undergoing PVI alone as the first ablation procedure. PVI may be a reasonable initial approach for PrAF ablation in pts with small LAV.Tabled 1Left Atrial (LA) volume as a predictor of AF recurrence using Cox regression analysis. CHF: Congestive Heart Failure. HTN: Hypertension. BMI: Body Mass Index.Variable (Ref)Estimatep-valueHazard ratio [95% CI]Age (Years)0.012±0.00110.2581.01 [0.99 - 1.03]Sex (Male)-0.291±0.2240.1950.75 [0.48 - 1.16]Baseline Fibrosis-0.006±0.0130.6590.99 [0.97 - 1.02]Antiarrhythmics history (Yes)-0.068±0.1980.7300.93 [0.63 - 1.38]CHF (Yes)0.151±0.2400.5291.16 [0.73 - 1.86]HTN (Yes)0.103±0.1930.5941.11 [0.76 - 1.62]History of Stroke (Yes)0.188±0.3110.5461.21 [0.66 - 2.22]Tobacco (Yes)0.264±0.1830.1491.30 [0.91 - 1.87]Failed antiarrhythmics treatment (Yes)0.107±0.1990.5931.11 [0.75 - 1.64]BMI0.026±0.0160.0941.03 [1.00 - 1.06]LA Volume (<114)-0.631±0.2190.0040.53 [0.35 - 0.82] Open table in a new tab