Management of thrombus formation after electrical isolation of the left atrial appendage in patients with atrial fibrillation.

AIMS: Left atrial appendage (LAA) electrical isolation (LAAEI) in addition to pulmonary vein isolation is an emerging catheter-based therapy to treat symptomatic atrial fibrillation. Previous studies found high incidences of LAA thrombus formation after LAAEI. This study sought to analyse therapeutic strategies aiming at the resolution of LAA thrombi and prevention of thromboembolism. METHODS AND RESULTS: Left atrial appendage electrical isolation was conducted via creation of left atrial linear lesions or cryoballoon ablation. Follow-up including transoesophageal echocardiography was conducted. In patients with LAA thrombus, oral anticoagulation (OAC) was adjusted until thrombus resolution was documented. Percutaneous LAA closure (LAAC) under use of a cerebral protection device was conducted in case of medically refractory LAA thrombi. Left atrial appendage thrombus was documented in 54 of 239 analysed patients who had undergone LAAEI. Thrombus resolution was documented in 39/51 patients (72.2%) with available follow-up after adjustment of OAC. Twenty-nine patients underwent LAAC and 10 patients were kept on OAC after LAAEI. No thromboembolic events or further LAA thrombi were documented after 553 ± 443 days of follow-up in these patients. Persistent LAA thrombi despite adaption of OAC was documented in 12/51 patients. One patient remained on OAC until the end of follow-up, while LAAC with a cerebral protection device was performed in 11 patients in the presence of LAA thrombus without complications. CONCLUSION: Left atrial appendage thrombus formation is common after LAAEI. Adjustment of OAC leads to LAA thrombus resolution in most patients. Left atrial appendage closure in the presence of LAA thrombi might be a feasible option in case of failed medical treatment.

Impact of Left Atrial Appendage Closure on LAA Thrombus Formation and Thromboembolism After LAA Isolation.

OBJECTIVES: This study sought to evaluate the safety and effectiveness of electrical isolation of the left atrial appendage (LAAEI) as well as the status of left atrial appendage closure (LAAC) in these patients. BACKGROUND: Catheter-based LAAEI is increasingly performed for treatment of symptomatic atrial fibrillation and pulmonary vein isolation nonresponders. Previous studies indicate an increased incidence of thromboembolic events after LAAEI despite effective oral anticoagulation. Interventional LAAC may prevent cardioembolic events after LAAEI but data regarding safety, feasibility, and efficacy of LAAC in this clinical setting are scarce. METHODS: Consecutive patients who underwent LAAEI at 2 German tertiary care hospitals were analyzed. RESULTS: A total of 270 patients underwent LAAEI by radiofrequency ablation in 255 (94.4%), cryoballoon ablation in 12 (4.4%), and by a combination of both techniques in 3 cases (1.1%). Stroke or transient ischemic attack occurred in 24 of 244 (9.8%) individuals with available follow-up. LAA thrombus formation was found in 53 patients (19.6%). A total of 150 patients underwent LAAC after LAAEI. No LAA thrombus was documented in any patient who underwent LAAC. Of the patients who underwent LAAEI, 67.6% were in sinus rhythm after a mean of 682.7 ± 61.7 days. LAA flow after LAAEI but not arrhythmia recurrence was identified as an independent predictor of stroke and/or transient ischemic attack or LAA thrombus (p < 0.0001). CONCLUSIONS: Sinus rhythm was documented in about two-third of patients undergoing LAAEI as treatment of therapy refractory atrial arrhythmias. LAAC potentially prevents LAA thrombus formation and thromboembolism.