New Radiomic Markers of Pulmonary Vein Morphology Associated With Post-Ablation Recurrence of Atrial Fibrillation.

Michael A Labarbera,Jonathan D Smith,Albert K Feeny,Tyler Roach,David R Van Wagoner,Meghan Mchale,Marjan Firouznia,Mina K Chung,Thomas Atta-Fosu,Anant Madabhushi,Catherine Cantlay,John Barnard,Paul Schoenhagen,Alexis Axtell

doi:10.1109/jtehm.2021.3134160

Abstract

Objective: To identify radiomic and clinical features associated with post-ablation recurrence of AF, given that cardiac morphologic changes are associated with persistent atrial fibrillation (AF), and initiating triggers of AF often arise from the pulmonary veins which are targeted in ablation. Methods: Subjects with pre-ablation contrast CT scans prior to first-time catheter ablation for AF between 2014–2016 were retrospectively identified. A training dataset (D1) was constructed from left atrial and pulmonary vein morphometric features extracted from equal numbers of consecutively included subjects with and without AF recurrence determined at 1 year. The top-performing combination of feature selection and classifier methods based on C-statistic was evaluated on a validation dataset (D2), composed of subjects retrospectively identified between 2005–2010. Clinical models (n}{}text{M}_{mathrm {C}}n) were similarly evaluated and compared to radiomic (n}{}text{M}_{mathrm {R}}n) and radiomic-clinical models (n}{}text{M}_{mathrm {RC}}n), each independently validated on D2. Results: Of 150 subjects in D1, 108 received radiofrequency ablation and 42 received cryoballoon. Radiomic features of recurrence included greater right carina angle, reduced anterior-posterior atrial diameter, greater atrial volume normalized to height, and steeper right inferior pulmonary vein angle. Clinical features predicting recurrence included older age, greater BMI, hypertension, and warfarin use; apixaban use was associated with reduced recurrence. AF recurrence was predicted with radio-frequency ablation models on D2 subjects with C-statistics of 0.68, 0.63, and 0.70 for radiomic, clinical, and combined feature models, though these were not prognostic in patients treated with cryoballoon. Conclusions: Pulmonary vein morphology associated with increased likelihood of AF recurrence within 1 year of catheter ablation was identified on cardiac CT. Significance: Radiomic and clinical features-based predictive models may assist in identifying atrial fibrillation ablation candidates with greatest likelihood of successful outcome.

Highlights

Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice, affecting 1-2% of the population [1], with lifetime risk of developing AF increasing to 37% after age 55 [2] [3] [4]
Initiation of AF typically results from extra-nodal electrical activation, most often from the pulmonary veins, which are the primary target of AF ablation [6]
Prior structural markers found to be associated with AF include pulmonary vein morphology [10], [11] and left atrial size [12]

Summary

Introduction

Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice, affecting 1-2% of the population [1] , with lifetime risk of developing AF increasing to 37% after age 55 [2] [3] [4]. Initiation of AF typically results from extra-nodal electrical activation, most often from the pulmonary veins, which are the primary target of AF ablation [6]. Comorbidities and AF itself can cause electrical and structural remodeling that limits success of pulmonary vein isolation (PVI) procedures. Prior structural markers found to be associated with AF include pulmonary vein morphology [10], [11] and left atrial size [12]. Differences in pulmonary vein morphology and radiomic (computer extracted measurements) assessment of the left atrium have potential in screening candidates for

Objectives

Methods

Results

Conclusion