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Appendage obliteration to reduce stroke in cardiac surgical patients with atrial fibrillation
1Division of Cardiovascular Diseases, Mayo Clinic Jacksonville, Florida, USA.
Insights
Left atrial appendage obliteration may prevent stroke in nonrheumatic atrial fibrillation. This procedure is more effective for nonrheumatic atrial fibrillation than rheumatic atrial fibrillation, as thrombi are more often isolated to the appendage.
Area of Science:
- Cardiology
- Vascular Surgery
- Neurology
Background:
- Left atrial appendage obliteration was historically ineffective for rheumatic atrial fibrillation stroke prevention.
- It is now a routine part of curative procedures for nonrheumatic atrial fibrillation.
Purpose of the Study:
- To assess the potential of left atrial appendage obliteration for stroke prevention in nonrheumatic atrial fibrillation.
- To evaluate the location and presence of left atrial thrombus in rheumatic and nonrheumatic atrial fibrillation patients.
Main Methods:
- Review of 23 studies on atrial fibrillation etiology and left atrial thrombus.
- Evaluation of thrombus presence and location via transesophageal echocardiography, autopsy, or operation.
Main Results:
- Left atrial thrombus was found in 13% of rheumatic and 17% of nonrheumatic atrial fibrillation patients.
- Thrombi extended into the left atrial cavity in 57% of rheumatic atrial fibrillation patients.
- Thrombi were isolated to the left atrial appendage in 91% of nonrheumatic atrial fibrillation patients (p < 0.0001).
Conclusions:
- Left atrial appendage obliteration shows potential for stroke prophylaxis in nonrheumatic atrial fibrillation.
- The localized nature of thrombi in nonrheumatic atrial fibrillation supports appendage obliteration.
Background:
Left atrial appendage obliteration was historically ineffective for the prevention of postoperative stroke in patients with rheumatic atrial fibrillation who underwent operative mitral valvotomy. It is, however, a routine part of modern "curative" operations for nonrheumatic atrial fibrillation, such as the maze and corridor procedures.
Methods:
To assess the potential of left atrial appendage obliteration to prevent stroke in nonrheumatic atrial fibrillation patients, we reviewed previous reports that identified the etiology of atrial fibrillation and evaluated the presence and location of left atrial thrombus by transesophageal echocardiography, autopsy, or operation.
Results:
Twenty-three separate studies were reviewed, and 446 of 3,504 (13%) rheumatic atrial fibrillation patients, and 222 of 1,288 (17%) nonrheumatic atrial fibrillation patients had a documented left atrial thrombus. Anticoagulation status was variable and not controlled for. Thrombi were localized to, or were present in the left atrial appendage and extended into the left atrial cavity in 254 of 446 (57%) of patients with rheumatic atrial fibrillation. In contrast, 201 of 222 (91%) of nonrheumatic atrial fibrillation-related left atrial thrombi were isolated to, or originated in the left atrial appendage (p < 0.0001).
Conclusions:
These data suggest that left atrial appendage obliteration is a strategy of potential value for stroke prophylaxis in nonrheumatic atrial fibrillation.
