Ineffective anticoagulation prior to elective electric cardioversion for atrial fibrillation. Results of transesophageal echocardiography

Abstract

Anticoagulation (AC) should be given for 3 to 4 weeks before elective electrical cardioversion to reduce thromboembolic events. During this period ineffective AC is a common problem. The aim of our study was to investigate the influence of the duration of ineffective AC on the incidence of left atrial thrombi (LAT) or spontaneous echocontrast (SEC) induced by hemostasis detected by transesophageal echocardiography (TEE). 56 consecutive patients (39 men) at the age of 64 +/- 9 years with non-rheumatic atrial fibrillation who were scheduled for electrical cardioversion after 3 to 4 weeks of AC and a documented ineffective AC underwent TEE. Cardioversion was performed after exclusion of a LAT by TEE or in patients with LAT after 4 more weeks of AC and repeated TEE. All patients received AC and were observed for at least 4 weeks after cardioversion. Echocardiographic, demographic and clinical parameters and available values of AC were recorded. In 5/56 (9 %) patients a LAT, in 10 (18 %) patients SEC was detected. No patient had both. In patients with LAT the duration of ineffective AC was 15 +/- 10 days (range 5 - 28) and did not differ significantly from patients without LAT (17 +/- 8 days; range 0 - 28) or to the group with SEC (23 +/- 6 days; range 12 - 28). There was no significant difference of demographic, echocardiographic and clinical parameters between these groups. There was no embolic event during follow-up. Neither the duration of ineffective AC nor clinical, epidemiologic or echocardiographic parameters could differentiate patients with or without LAT in our observed groups with small numbers of patients. In case of an ineffective AC patients who are to undergo electrical cardioversion should have TEE. In our study patients with SEC were not at a higher thromboembolic risk.