Abstract 1830: Long-term Results After TEE-Guided Electrical Cardioversion of Atrial Fibrillation Using a Short Term Anticoagulation Strategy With Enoxaparin. Relevance of LAA Flow for an Event Free Outcome.
Background: After electrical cardioversion (eCV) of atrial fibrillation (AF) atrial stunning lasts for about one week or more in most patients, leading to the risk of cardioembolic complications. After successful eCV risk of embolization persists due to recurrent continuous or paroxysmal AF. In this study we evaluated, if one week of subcutaneous enoxaparin treatment after TEE-guided eCV in combination with analysis of left atrial appendage (LAA) flow velocity assessed before and one week after eCV with TEE can predict an event free short- and longterm outcome.
Methods: In 70 consecutive patients (pts) (65 ± 8 years; 52 men) with non-valvular AF (>1 week and < 1 year of duration) after one day of enoxaparin treatment (0,1 mg/kg bodyweight two times daily) TEE-guided eCV was performed after intracardial thrombus was excluded and if LAA flow was > 20 cm/s. After successful eCV enoxaparin treatment was continued for 7 days until a 2nd TEE was performed: If LAA flow was > 40 cm/s at that time and pts were still in sinusrhythm, enoxaparin was discontinued, if LAA flow velocity was < 40 cm/s or in case of recurrence of AF longterm phenprocoumon treatment was initiated.
Results: 60/70 (86%) pts with LAA flow > 20 cm/s by the 1st TEE and successful eCV were included in the analysis of primary endpoints (composite of all-cause mortality, ischemic and embolic events and major bleeding complications). 7 days after eCV 51/60 (85%) pts in sinus rhythm showed an LAA flow velocity > 40 cm/s, leading to discontinuation of enoxaparin therapy. In 9/60 patients with LAA flow velocity < 40 cm/s and/or recurrence of AF treatment with phenprocoumon was started. After the observation period of 1 year 28/51 (55%) pts were in sinus rhythm; in none of the 51 pts, regardless if presenting with sinus rhythm or AF, periinterventional or longterm thromboembolic events, bleeding complications or death had occurred.
Conclusions: This study suggests that the assessment of LAA flow dynamics before and one week after eCV allows the detection of a low risc group and the decision to discontinue post eCV enoxaparin anticoagulation therapy after 1 week; LAA flow > 40 cm/s predicts an event free longterm outcome, even if sinus rhythm is not preserved.