Korean Circ J.  2009 Nov;39(11):443-458. 10.4070/kcj.2009.39.11.443.

Cardioembolic Stroke in Atrial Fibrillation-Rationale for Preventive Closure of the Left Atrial Appendage

• Leithauser B
• Park JW

• KMID: 2225646
• DOI: http://doi.org/10.4070/kcj.2009.39.11.443

Abstract

Atrial fibrillation is the most common cardiac arrhythmias, and a major cause of morbidity and mortality due to cardioembolic stroke. The left atrial appendage is the major site of thrombus formation in non-valvular atrial fibrillation. Loss of atrial systole in atrial fibrillation and increased relative risk of associated stroke point strongly toward a role for stasis of blood in left atrial thrombosis, although thrombus formation is multifactorial, and much more than blood flow irregularities are implicated. Oral anticoagulation with vitamin-K-antagonists is currently the most effective prophylaxis for stroke in atrial fibrillation. Unfortunately, this treatment is often contraindicated, particularly in the elderly, in whom risk of stroke is high. Moreover, given the risk of major bleeding, there is reason to be skeptical of the net benefit when warfarin is used in those patients. This work reviews the pathophysiology of cardioembolic stroke and critically spotlights the current status of preventive anticoagulation therapy. Various techniques to exclude the left atrial appendage from circulation were discussed as a considerable alternative for stroke prophylaxis.

Keyword

Atrial appendage; Atrial fibrillation; Thromboembolism; Stroke; Prostheses and implants; Prognosis

MeSH Terms

Aged
Arrhythmias, Cardiac
Atrial Appendage
Atrial Fibrillation
Hemorrhage
Humans
Prognosis
Prostheses and Implants
Stroke
Systole
Thromboembolism
Thrombosis
Warfarin
Warfarin

Figure

• 

  Fig. 1 Angiographic contrast filling defect in the contast shadow of the LAA (white arrows) indicating a spherical thrombus, which was not diagnosed by TOE. Note the TOE probe at the left margin and the loop of the pigtail catheter (striped arrow), indicating the position of the aortic valve. LAA: left atrial appendage, TOE: transoesophageal echocardiography.

• 

  Fig. 2 The AMPLATZER Cardiac Plug (ACP). On the right, the ideal position within the LAA is sketched. The lobe of the device is anchored in the "landing zone" 1-2 cm distal of the LAA orifice, while the disc fully covers the outer shape and enables endothelialization from the surrounding atrial wall. These images were provided by, and are property of AGA, Inc., Minneapolis, MN, USA. LAA: left atrial appendage.

• 

  Fig. 3 Images of the AMPLATZER Cardiac Plug (ACP) in situ. A: TOE. B: fluoroscopy after implantation.

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