Potential clinical efficacy and cost benefit of a transesophageal echocardiography-guided low-molecular-weight heparin (enoxaparin) approach to antithrombotic therapy in patients undergoing immediate cardioversion from atrial fibrillation.

An alternative clinical management strategy and cost analysis model is presented for patients with atrial fibrillation of >2 days' duration who may benefit from immediate cardioversion with self-administered low-molecular-weight heparin (enoxaparin) as a bridge antithrombotic therapy to warfarin, after a negative transesophageal echo-cardiography (TEE) screening for thrombus. Assuming no difference in stroke or bleeding rates, our cost minimization model shows that the TEE-guided enoxaparin treatment costs are $1353 lower per patient than an intravenous unfractionated heparin approach. Sensitivity analyses for stroke and bleeding reveal that the treatment-cost economic dominance of the TEE-guided enoxaparin approach may be enhanced by an expected improvement in clinical outcome.

Right atrial spontaneous echo contrast and thrombi in atrial fibrillation: a transesophageal echocardiography study.

BACKGROUND: Previous studies have reported the clinical and echocardiographic findings of patients with left atrial spontaneous echo contrast (SEC) and thrombi. We sought to study these characteristics in patients with right atrial SEC and thrombi. METHODS: We reviewed 580 consecutive patients from the ACUTE (Assessment of Cardioversion Using Transesophageal Echocardiography) Registry and found 79 patients (14%, aged 67 +/-13 years, 67 male) with transesophageal echocardiography (TEE) findings of right atrial SEC or thrombi (group 1). This group was compared with a control group of 75 consecutive patients (group 2) (aged 68 +/- 13 years, P = not significant; 49 male, P <.005) from the registry with no TEE findings of SEC or thrombi in the left or right atrium. RESULTS: Atrial fibrillation was present in 60 of 79 group 1 patients (76%). Five right atrial (6%) and 11 left atrial (14%) thrombi were identified. Both left ventricular ejection fraction (39% +/- 16% versus 47% +/- 14%; P =.0005) and presence of right ventricular dysfunction (n = 44 versus 18; P =.0001) differed significantly between groups 1 and 2, respectively. Right atrial area (24 +/- 6 cm(2) versus 22 +/- 6 cm(2); P = .02) was larger in patients in group 1. Left atrial SEC was present in 68 of 79 group 1 patients (86%). Patients with right atrial thrombi and right atrial SEC had a longer duration of arrhythmia (524 +/-812 days versus 147 +/-368 days, P <.05) than patients with right atrial SEC only. CONCLUSIONS: Right atrial SEC has a prevalence of 14% in patients with atrial arrhythmia who undergo TEE-guided cardioversion. Right atrial thrombi are a rare finding and were seen in fewer than 1% (5/580) of patients with atrial arrhythmia. Right atrial thrombi among patients on anticoagulation therapy were not associated with clinically significant pulmonary embolism.

National use of the transesophageal echocardiographic-guided approach to cardioversion for patients in atrial fibrillation.

Transesophageal echocardiographic (TEE)-guided cardioversion of patients in atrial fibrillation (AF) of >2 days' duration is used as an alternative to conventional therapy. The purpose of this study was to investigate practice patterns employed for stroke prophylaxis in patients with AF who underwent cardioversion, and to determine the relative use of conventional and TEE-guided management strategies. We forwarded regionally stratified survey questionnaires to 947 clinical practices within the United States. The 10-question questionnaire queried demographic and clinical practice volumes and practices for managing patients with AF who underwent cardioversion. In addition, we used historical data to determine longitudinal use patterns of the TEE-guided approach for a large institution over 7 years. The 197 completed and returned surveys yielded a return rate of 20.8%. The TEE-guided approach was employed in approximately 12% of total cardioversions, but 75% of practices indicated that they employed transesophageal echocardiography only occasionally. The TEE-guided approach was associated with community size (r = 0.19; p<0.008), type of practice (r = 0.26; p = 0.001), total use of transesophageal echocardiography (r = 0.48; p<0.001), and volume of cardioversions (r = 0.28; p<0.001). Importantly, there was little consensus on the most appropriate clinical indications for TEE-guided cardioversions, and the proportions of TEE-guided cardioversion to total number of electrical cardioversions remained stable over 7 years. Practice volume and physician training may be the most important variables in the adoption of the TEE approach.

Transesophageal echocardiography guided enoxaparin antithrombotic strategy for cardioversion of atrial fibrillation: the ACUTE II pilot study.

BACKGROUND: Patients with atrial fibrillation >2 days' duration for whom immediate cardioversion is desired or required are commonly hospitalized for 4 or more days of antithrombotic therapy with intravenous unfractionated heparin and commencement of oral warfarin. For these early cardioversion patients, self-administered low-molecular-weight heparin (enoxaparin sodium) as "bridge" therapy to warfarin may obviate the need for hospitalization and activated partial thromboplastin time monitoring and thus potentially lower costs and enhance utility. OBJECTIVE: To compare feasibility and safety of a transesophageal echocardiography (TEE)-guided enoxaparin strategy with those of a TEE-guided unfractionated heparin strategy in patients with atrial fibrillation of >2 days' duration undergoing early electrical or chemical cardioversion. DESIGN AND SETTING: This is a randomized, multicenter clinical trial at 11 hospitals in the United States. PATIENTS AND INTERVENTION: Two hundred patients with atrial fibrillation >2 days' duration requiring early chemical or electric cardioversion will be enrolled. TEE-guided intravenous unfractionated heparin bridge therapy will be compared with TEE-guided subcutaneous enoxaparin bridge therapy. OUTCOME MEASURES: Feasibility outcomes are time to hospital discharge, patient quality of life/utility, treatment costs, and sinus rhythm. Safety outcomes are ischemic stroke, transient ischemic attack, systemic embolization, major and minor bleeding, clinical hemodynamic instability, and cardiac and cardioversion-related death for a 5-week period from enrollment. CLINICAL IMPLICATIONS: The results of this pilot study will have important clinical and economic implications for the antithrombotic management of patients with atrial fibrillation undergoing TEE-guided cardioversion.