Left atrial volumetric and functional remodeling post-pulmonary vein isolation: Insights from cardiac magnetic...

Atrial fibrillation (AF) ablation may induce reverse left atrial (LA) remodeling, yet few studies have prospectively evaluated its short- and long-term effects. This study assessed LA volumetric and functional remodeling using cardiovascular magnetic resonance (CMR) imaging early and late after pulmonary vein isolation (PVI) in AF patients.

This study involved 61 AF patients undergoing radiofrequency PVI. CMR scans were performed pre-PVI, within 72 h and 3months post-PVI. LA volumes and strain were assessed using two- and four-chamber cine images. Early AF recurrence was monitored during 3months follow-up.

LAVImin significantly increased early post-PVI (22.5±8.7 mL/m² to 25.8±9.9 mL/m², p<0.01). At 3months, both LAVImin and LAVImax significantly reduced compared to early post-PVI (25.4±8.87 mL/m² to 19.4±7.7 mL/m², p<0.001; 48.2±12.7 mL/m² to 38.7±10.6 mL/m², p<0.001, respectively), as well as compared to baseline (22.5±8.7 mL/m² to 20.1±8.5 mL/m², p=0.04; 45.6±11.8 mL/m² to 39.3±11.2 mL/m², p<0.001, respectively). Early post-PVI, LA emptying fraction (LA EF), LA reservoir, and contractile strain significantly reduced compared to baseline (from 51.6±10.8% to 47.1±8.9%, p<0.01; 18.3±4.4% to 15.4±2.9%, p<0.001; 8.3±3.1% to 5.4±1.8%, p<0.001, respectively). At 3months, LA EF, LA reservoir, and contractile strain significantly increased as compared to early post-PVI (from 47.1±8.9% to 50.5±8.6%, p<0.01; 15.4±2.9% to 16.8±3.1%, p<0.01; 5.4±1.8% to 6.9±2.3%, p<0.001, respectively). However, LA reservoir and contractile strain remained significantly lower compared to baseline (18.3±4.4% to 16.8±3.1%, p=0.02; 8.3±3.1% to 6.9±2.3%, p<0.01, respectively). In patients with early AF recurrence 27.9% (17/61), LA volume reduction and partial functional recovery were not observed during 3months post-PVI.

LA volumes significantly reduced 3months post-PVI. While LA function initially declined, it showed partial recovery at 3months. However, LA reservoir and contractile strain remained reduced compared to pre-PVI. LA reverse remodeling and partial LA functional recovery only occurred in patients without early AF recurrence.