Left Atrial Function Predicts Atrial Arrhythmia Recurrence Following Ablation of Long-Standing Persistent Atrial Fibrillation.

Background: Left atrial (LA) function following catheter or surgical ablation of de-novo long-standing persistent atrial fibrillation (AF) and its impact on AF recurrence was studied in patients participating in the CASA-AF trial (Catheter Ablation vs. Thoracoscopic Surgical Ablation in Long Standing Persistent Atrial Fibrillation).
Methods: All patients underwent echocardiography preablation, 3 and 12 months post-ablation. LA structure and function were assessed by 2-dimensional volume and speckle tracking strain measurements of LA reservoir, conduit, and contractile strain. Left ventricular diastolic function was measured using transmitral Doppler filling velocities and myocardial tissue Doppler velocities to derive the e', E/e', and E/A ratios. Continuous rhythm monitoring was achieved using an implantable loop recorder.
Results: Eighty-three patients had echocardiographic data suitable for analysis. Their mean age was 63.6±9.7 years, 73.5% were male, had AF for 22.8±11.6 months, and had a mean LA maximum volume of 48.8±13.8 mL/m ² . Thirty patients maintained sinus rhythm, and 53 developed AF recurrence. Ablation led to similar reductions in LA volumes at follow-up in both rhythm groups. However, higher LA emptying fraction (36.3±10.6% versus 27.9±9.9%; P <0.001), reservoir strain (22.6±8.5% versus 16.7±5.7%; P =0.001), and contractile strain (9.2±3.4% versus 5.6±2.5%; P <0.001) were noted in the sinus rhythm compared with AF recurrence group following ablation at 3 months. Diastolic function was better in the sinus rhythm compared with the AF recurrence group with an E/A ratio of 1.5±0.5 versus 2.2±1.2 ( P <0.001) and left ventricular E/e' ratio of 8.0±2.1 versus 10.3±4.1 ( P <0.001), respectively. LA contractile strain at 3 months was the only independent predictor of AF recurrence.
Conclusions: Following ablation for long-standing persistent AF, improvement in LA function was greater in those who maintained sinus rhythm. LA contractile strain at 3 months was the most important determinant of AF recurrence following ablation.
Registration: URL: https://www.
Clinicaltrials: gov; Unique identifier: NCT02755688.
Competing Interests: Disclosures Dr Khan received presentation fees from CHRS and NIHR grant (EME 12/127/127); Dr Haldar received a grant from NIHR (EME 12/127/127), Abbott, presentation fees from Alivecor and Zurich Heart House; Dr Bahrami received honoraria fees from Medtronic and meeting support from Edwards Lifesciences; Dr De Souza received presentation/support fees from Medtronic and Atricure. Dr De Souza is serving as BISICS President; Dr Markides received educational grants, consultancy fees, and honoraria from Biosense Webster; Dr Jones receives institutional research grants from Biosense Webster, Boston Scientific, and Medtronic; the rest of the authors disclose no conflicts of interest.