Left atrial strain is associated with atrial fibrillation recurrence after catheter ablation. Data from the ISOLATION registry

Abstract Background Catheter ablation (CA) has been established as an effective therapeutic option to achieve rhythm control in patients with atrial fibrillation (AF). However, AF recurrence occurs in approximately one-third of the patients undergoing CA. The association between AF recurrence after CA and left atrial (LA) strain, which is a surrogate marker of LA mechanical dysfunction already appearing before the enlargement of the LA, remains less clear. Aim The purpose of this study was to evaluate the association between LA function assessed by strain echocardiography and AF recurrence after CA. Methods This study involved consecutive patients with paroxysmal or persistent AF scheduled for cryoballoon or radiofrequency CA. Clinical characteristics and echocardiography examination were collected at baseline visit before CA. Patients were followed for 12 months. Follow-up consisted of outpatient visits and heart rhythm monitoring (48 day Holter, 12-lead electrocardiogram, 7 day photoplethysmography-based rhythm app) at 3, 6, and 12 months. Results We analyzed 600 patients (median age 65, 36% women). More than half (59%; n=351) underwent radiofrequency CA and 28% (n=169) had AF recurrence within one year follow-up. Patients with recurrent AF were older, more often women, expect higher prevalence of persistent AF, previous electrical cardioversion and diabetes compared to those without AF recurrences. LA reservoir strain (28 [23-35]% vs 33 [25-39]%, p<0.001), LA conduit strain (15 [12-19]% vs 18 [14-24]%, p<0.001) and LA contraction strain (12 [8.7-16]% vs 13 [8.9-17]%, p<0.001), were significantly lower, and mildly-to-severe LA enlargement (LA volume index ≥34 mL/m2) was more frequently observed (76% vs 66%, p=0.031) in patients with (vs without) recurrence of AF. Based on multiple logistic regression, from echocardiographic parameters, only LA reservoir strain were independent predictors for AF recurrence (OR 0.97, 95%CI 0.96-0.99), even in the group of patients with mildly-to-severe enlarged LA (0R 0.97, 95%CI 0.96-0.99). Conclusions LA function assessed by LA strain is associated with AF recurrence after CA, even in patients with dilated LA. Whether integration of results derived from systematic preprocedural LA strain analysis into patients’ selection strategies may help to identify patients profiting from CA required further study.