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Updated: Mar 2, 2026

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation
Published on: February 26, 2013
Left Atrial Appendage Thrombus Despite Anticoagulation
Viorel G Florea1, Venkatakrishna N Tholakanahalli1, Selcuk A Adabag1
1Section of Cardiology, Minneapolis Veterans Affairs Health Care System.
Insights
Despite adequate anticoagulation, left atrial appendage thrombi were found in patients undergoing cardioversion. Transesophageal echocardiography before cardioversion may improve safety for atrial fibrillation patients.
Area of Science:
- Cardiology
- Cardiovascular Medicine
Background:
- Current guidelines recommend 3 weeks of anticoagulation before cardioversion for atrial fibrillation (AF) of unknown or long duration.
- Atrial fibrillation and heart failure are significant cardiovascular epidemics with shared risk factors and accelerated progression.
- The interplay between AF and heart failure involves complex hemodynamic, neuro-hormonal, inflammatory, and electrophysiologic mechanisms.
Observation:
- A case report identified left atrial appendage thrombi despite adherence to recommended anticoagulation protocols.
- This finding challenges the established practice guidelines for cardioversion in atrial fibrillation.
Findings:
- Adequate anticoagulation may not always prevent thrombus formation in the left atrial appendage.
- Transesophageal echocardiography (TEE) is crucial for detecting thrombi before cardioversion.
Implications:
- TEE prior to cardioversion may enhance thromboembolic safety, especially in patients with atrial fibrillation.
- Further research is needed to refine anticoagulation strategies and improve cardioversion safety.
- Understanding the complex relationship between atrial fibrillation and heart failure is critical for managing these co-existing conditions.
Abstract:
The American College of Cardiology Foundation/American Heart Association task force on practice guidelines recommend therapeutic anticoagulation for at least 3 weeks prior to cardioversion in patients with atrial fibrillation of 48-hour duration or longer, or when the duration of atrial fibrillation is unknown. This case report demonstrates the presence of thrombi in the left atrial appendage despite adequate anticoagulation, challenging the current guidelines. Therapeutic anticoagulation for at least 3 weeks followed by transesophageal echocardiography in search of thrombus may enhance thromboembolic safety of elective cardioversion. Atrial fibrillation (AF) and heart failure (HF) have emerged as major cardiovascular epidemics in developed nations over the past decade. They share similar risk factors, seem to mutually accelerate progression and are associated with increased morbidity and mortality. Their relationship involves complex hemodynamic, neuro-hormonal, inflammatory and electrophysiologic mechanisms, which go beyond just mutual risk factors. This review focuses on updates in AF and HF with a hope of better understanding this relationship and the management of this complex duo.
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