Routine Transthoracic Echocardiography to Assess Pericardial Collections in Patients After Extensive Left Atrial Catheter Ablation: A Prospective Study

INTRODUCTION: Little is known about the incidence and timing of reactive pericardial collections developing after left atrial catheter ablation (LACA), and when and if transthoracic echocardiography (TTE) should be performed routinely in these patients postprocedure. METHODS AND RESULTS: Two hundred consecutive LACA patients for persistent atrial fibrillation (AF) (107), paroxysmal AF (75) or atrial tachycardia (AT) (18) underwent on-table TTE at the end of the procedure, and the next day prior to discharge. One patient developed tamponade at the time of transseptal puncture. Thirty-three percent of the remaining 199 who underwent on-table TTE, had a pericardial collection. On next day TTE, there were significantly more pericardial collections (53%, P < 0.0001). Persistent rather than paroxysmal arrhythmia at the time of the procedure was the only predictor of a pericardial collection, either on-table (χ(2)= 9.64; P = 0.002) or next day (χ(2)= 5.95; P = 0.02). Eight patients had collections on next day TTE ≥ 1.5 cm. One needed drainage because of clinical tamponade. Repeated TTEs in the other 7 patients demonstrated resolution of collections over 1-2 weeks. CONCLUSION: Pericardial collections are common in LACA patients. Almost all are not associated with clinical compromise. The only predictor of collection size is arrhythmia type at ablation, which may correspond to ablation at sites specific to persistent rather than paroxysmal arrhythmias. Performing on-table TTE routinely may help guide immediate anticoagulation protocols, but even larger on-table collections are not associated with tamponade and resolve spontaneously. TTE does not need to be performed routinely unless there are clinical signs of tamponade.