Economic analysis of a transesophageal echocardiography-guided approach to cardioversion of patients with atrial fibrillation

Transoesophageal echocardiography before DC cardioversion: a survey of clinical practice in the UK

Transoesophageal echocardiography (TOE) can be used to expedite DC cardioversion (DCCV) in the absence of adequate anticoagulation. There are no guidelines for the management of sedation or general anaesthetic. We performed a survey of NHS echocardiography departments to determine UK practice. Responses were received from 95 (50%) of 189 centres, and TOE-guided DCCV was performed in 81 centres. The numbers were <10 a year in 41 (50%), 10 – 50 in 31 (38%), 50 – 100 in 8 (10%) and >100 in 4 (5%) centres. Sedation for TOE was a usual practice in 67 (80%) centres but often temporally disconnected from DCCV due to logistical reasons. TOE under general anaesthetic was performed in 35 (43%) centres and as the usual method in 16 (20%). The patient was in the supine position with endotracheal intubation in 20 (57%) of centres, but without any form of airway protection while supine in 5 (14%). There is variability in practice across centres in the UK, in part due to limitations to services in most centres but also because of an absence of UK guidelines. The development of national standards may address this and aid in the development of local business cases to extend services.

Effect of early direct current cardioversion on the recurrence of atrial fibrillation in patients with persistent atrial fibrillation

In patients with persistent atrial fibrillation (AF), the sinus rhythm (SR) can be restored by direct current cardioversion (DCC), although the recurrence of AF after successful DCC is common. We examined whether transesophageal echocardiography (TEE)-guided early DCC, compared with the conventional approach of DCC after 3 weeks of anticoagulation with dabigatran-etexilat, reduces the recurrence of AF. A total of 126 consecutive patients with persistent AF were randomly assigned to a TEE followed by early DCC (n = 65) or to a conventional treatment with dabigatran-etexilat for 3 weeks followed by DCC (n = 61). None of the patients received any antiarrhythmic treatment other than β blockers, and all the DCCs were successful. Forty-eight-hour Holter monitoring was performed at 28 days and at 3, 6, and 12 months after the DCC. The primary outcome was AF recurrence lasting ≥30 seconds. The analysis was stratified by AF duration <60 (n = 62) or >60 days (n = 64) before DCC. We observed a significant reduction in the AF recurrence risk (p = 0.003) in patients with persistent AF <60 days who received early DCC, but there was no significant benefit of early DCC (p = 0.456) in patients with persistent AF lasting >60 days. The recurrence-free survival probability at 28 days in patients with persistent AF <60 days was 0.27 (95% confidence interval 0.14 to 0.51) in the conventional treatment group compared with 0.69 (95% confidence interval 0.54 to 0.87; p = 0.006) in the early DCC group. A benefit of early DCC persisted throughout 12 months of follow-up. In conclusion, TEE-guided early DCC in patients with persistent AF <60 days results in a significant reduction of AF recurrence.

Conventional oral anticoagulation may not replace prior transesophageal echocardiography for the patients with planned catheter ablation for atrial fibrillation

INSTRUCTION

Preablation transesophageal echocardiography (TEE) is dispensable for the patients with planned catheter ablation for atrial fibrillation (AF) and having received at least a 3-week oral anticoagulation therapy according to the recommendations of the Venice Consensus. But the role of prior TEE and the effect of preablation short-term oral anticoagulation drugs (OACs) under the circumstance are still unclear.

METHODS AND RESULTS

A total of 188 patients with planned catheter ablation for AF and without previous long-term oral anticoagulation, whose duration of AF exceeded 48 h, were randomly divided into receiving 3-week OACs (OACs group) before heparin bridging or receiving no prior OACs (N-OACs group). Follow-up was performed until a TEE had been performed on all the cases before ablation. Consequently, the prevalence of atrial thrombi is 6.3% and 11.7%, respectively (P < 0.05), and the prevalence of minor bleeding is 5.3% and 0%, respectively (P < 0.05), in OACs and N-OACs group. There was no thrombotic event, major hemorrhage, in both groups.

CONCLUSION

After a 3-week effective oral anticoagulation, atrial thrombi could be resolved partly but not completely in the patients with AF who had not received long-term oral anticoagulation previously. To ensure safety, prior TEE may be necessary for the patients with planned catheter ablation for AF.

Cost in the use of enoxaparin compared with unfractionated heparin in patients with atrial fibrillation undergoing a transesophageal echocardiography-guided cardioversion (from Assessment of Cardioversion using Transesophageal Echocardiography [ACUTE] II randomized multicenter study)

The ACUTE II study demonstrated that transesophageal echocardiographically guided cardioversion with enoxaparin in patients with atrial fibrillation was associated with shorter initial hospital stay, more normal sinus rhythm at 5 weeks, and no significant differences in stroke, bleeding, or death compared with unfractionated heparin (UFH). The present study evaluated resource use and costs in enoxaparin (n=76) and UFH (n=79) during 5-week follow-up. Resources included initial and subsequent hospitalizations, study drugs, outpatient services, and emergency room visits. Two costing approaches were employed for the hospitalization costing. The first approach was based on the UB-92 formulation of hospital bill and diagnosis-related group. The second approach was based on UB-92 and imputation using multivariable linear regression. Costs for outpatient and emergency room visits were determined from the Medicare fee schedule. Sensitivity analysis was performed to assess the robustness of the results. A bootstrap resample approach was used to obtain the confidence interval (CI) for the cost differences. Costs of initial and subsequent hospitalizations, outpatient procedures, and emergency room visits were lower in the enoxaparin group. Average total costs remained significantly lower for the enoxaparin group for the 2 costing approaches ($5,800 vs $8,167, difference $2,367, 95% CI 855 to 4,388, for the first approach; $7,942 vs $10,076, difference $2,134, 95% CI 437 to 4,207, for the second approach). Sensitivity analysis showed that cost differences between strategies are robust to variation of drug costs. In conclusion, the use of enoxaparin as a bridging therapy is a cost-saving strategy (similar clinical outcomes and lower costs) for atrial fibrillation.

Single-step atrial thrombus exclusion and transesophageal cardioversion in atrial fibrillation

Atrial fibrillation (AF), the most common arrhythmia, has a major impact on both patient morbidity and healthcare economics. Hospital admissions due to AF have risen by two-thirds in the last 20 years. This is due mainly to an aging population and an increasing prevalence of chronic heart disease. Strategies for the management of AF include prevention of thromboembolism, rate control and correction of the arrhythmia. Electrical cardioversion as one component of the treatment of AF requires the absence of atrial thrombi. Transesophageal echocardiography is used routinely for exclusion of atrial thrombi prior to cardioversion in many hospitals. This review presents preliminary data on the clinical use of devices for simultaneous transesophageal echocardiography and transesophageal cardioversion.

Utility of transesophageal echocardiography in identification of thrombogenic milieu in patients with atrial fibrillation (an ACUTE ancillary study)

The ACUTE trial randomly assigned patients who had atrial fibrillation (AF) of >2 days' duration to a transesophageal echocardiographically guided or a conventional strategy before cardioversion. In the 571 patients who underwent transesophageal echocardiography (TEE) in the ACUTE trial, we assessed the relative predictive value of baseline data derived by history, transthoracic echocardiography, and TEE for prediction of thrombus and adjudicated embolism (thromboembolism) as a composite end point. TEE was performed at 70 centers in 571 patients, 549 in the transesophageal echocardiographically guided group and 22 crossovers in the conventional group. Six patients (1.1%) who had embolism and 79 (13.8%) who had thrombi were identified in this group. Thrombus was completely resolved in 76.5% of patients who had repeat transesophageal echocardiographic procedures after 31.7 +/- 7.5 days of anticoagulation. For patients who had embolic events, none had a transesophageal echocardiographically identified thrombus; 5 of 6 (83.3%) had >/=1 transesophageal echocardiographic risk factors (including spontaneous echocardiographic contrast, aortic atheroma, patent foramen ovale, atrial septal aneurysm, mitral valve strands), and 4 of 6 (66.66%) had subtherapeutic anticoagulation or no anticoagulation. Clinical, transthoracic echocardiographic, and transesophageal echocardiographic risk factors contributed significantly to the prediction of composite thrombus/embolism. However, transesophageal echocardiographic thromboembolic risk factors were the strongest predictors of thromboembolism and provided statistically significant incremental value (chi-square 38.0, p <0.001) for identification of risk. Thus, in addition to thrombus identification, TEE has significant incremental value in the identification of patients who had high thromboembolic risk. In conclusion, this study supports the role of TEE and anticoagulation monitoring in patients who have atrial fibrillation and is useful for identifying thromboembolic risk factors.