Left atrial strain for predicting arrhythmia recurrence after atrial fibrillation ablation: cardiac magnetic resonance rapid strain vs. feature tracking strain
Abstract Background Global left atrial (LA) strain is a predictor of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). Recently, novel rapid LA strain assessment approaches have emerged: LA long axis strain and LA AV junction strain. Currently, it remains unknown whether these rapid strain approaches can predict AF recurrence after AF ablative therapy and hence may be a simple alternative for the cumbersome LA feature tracking strain analysis. Purpose The present study focusses on the predictive value of different atrial strain quantification methods in relation to AF recurrence after PVI. Rapid LA strain analysis is compared to LA feature tracking strain in AF patients. Methods A total of 58 AF patients (78% paroxysmal AF, 64% male, mean age 61±7 years) undergoing first radiofrequency PVI ablation were included. Prior to ablation, all patients underwent cardiac magnetic resonance imaging being in sinus rhythm. LA rapid strain (long axis strain and AV junction strain) and LA feature tracking strain were derived from 2-chamber and 4-chamber cine CMR images. All patients were routinely followed up for arrhythmia recurrence through 12-lead ECGs, mobile-based one-lead ECGs, and/or Holter monitoring. Results After one year follow-up, arrhythmia recurrence (after the 90-day blanking period) was observed in 21 patients (36%), occurring after a median of 159 (119–320) days. LA long axis strain, AV junction strain, and feature tracking strain were all significantly reduced in patients with AF recurrence compared to patients without AF recurrence (long axis strain: −19.96±11.03% vs. −28.18±9.93%, P=0.005; AV junction strain: −18.08±9.69% vs. −25.60±8.79%, P=0.004; feature tracking strain: −12.54±4.16% vs. −15.94±3.50%, P=0.002, respectively, figure A to C). ROC analysis identified LA feature tracking strain as having the highest area under the curve (AUC) for predicting AF recurrence after ablative therapy (AUC: 0.75 for LA feature tracking strain, 0.71 for LA long axis strain, 0.70 for AV junction strain, figure D). Both LA rapid strain methods had a significant correlation with LA feature tracking strain (LA long axis strain vs. LA feature tracking strain, r=0.76, P<0.001 and LA AV junction strain vs. LA feature tracking strain, r=0.77, P<0.001). Conclusion LA rapid strain and LA feature tracking strain both have clinically relevant predictive power for prediction of AF recurrence after index PVI in AF patients. Considering the ease of LA rapid strain analysis, this method may be a valuable parameter to assess in clinical practice. FUNDunding Acknowledgement Type of funding sources: None. Figure 1
