Left Atrial Appendage Occlusion in the Management of Stroke in Patients With Atrial Fibrillation

Left Atrial Appendage Closure: What Do We Know?

Atrial fibrillation (AF) is the most common arrhythmia in the United States and the most common cause of embolic cerebrovascular events, with the majority of these thrombi originating in the left atrial appendage. The left atrial appendage (LAA) has separate developmental, ultrastructural, and physiological characteristics from the left atrium. Although LAA anatomy is highly variable, it can be categorized into 4 types: cactus, cauliflower, chicken wing, and windsock. The cauliflower type is associated with higher stroke risk in patients with nonvalvular AF. Although the cornerstone of therapy to prevent embolic strokes from AF has been anticoagulation with thrombin inhibitors, a large group of patients are unable to tolerate anticoagulation due to bleeding. This has led to the development and advancement of multiple surgical and percutaneous LAA closure devices to prevent embolic cerebrovascular accidents without the need for anticoagulation. In this article, we discuss the outcomes of major studies that utilized surgical LAA occlusion and its effectiveness. Furthermore, we summarize nonsurgical methods of LAA closure and future directions regarding LAA closure.

Long-Term Effect of Left Atrial Appendage Occlusion in Treating Patients with Previous Ischemic Stroke on the Disease Recurrence

Methods

A total of 120 patients with IS admitted to Tangdu Hospital from July 2016 to September 2017 were grouped into the control group (n = 60) and the observation group (n = 60). Patients in the control group were only treated with thrombolytics and anticoagulants while those in the observation group were treated with both drugs and LAAO. Transesophageal echocardiography (TEE) was performed to observe the occlusion of LAA in patients in the observation group after 45 d and 6 months, respectively. Clinical outcomes in two groups were compared from the following aspects: recurrence of IS, incidence of systemic embolism, and the 3-year recurrence-free survival (RFS). The 3-year IS recurrence of patients was compared by Fisher's exact test.

Results

No significant differences were observed at baseline levels (age, sex, etc.) between the observation group and control group (p > 0.05). During follow-up visit of 45 d and 6 months, all occluders met the efficacious occludsion criteria. The results of TEE at 45 d after LAAO showed that 50% of patients (30/60) in the observation group had complete occlusion of LAA. The results of TEE at 6 months after LAAO suggested that 58.3% of patients (35/60) had complete occlusion of LAA. IS recurrence in the observation group (3.33%, 2/60) was significantly lower than that in the control group (18.33%, 11/60), with the difference presenting statistical significance (p = 0.008). Incidence of systemic embolism in the observation group (1.67%, 1/60) was markedly lower than that in the control group (13.33%, 11/60) (p = 0.014). The average RFS in the observation group (31.97 months, 95% CI: 27.50~32.31 months) was notably longer than that in the control group (29.91 months, 95% CI: 29.85~32.92 months) (p < 0.05). The 3-year IS recurrence of patients between two groups compared by Fisher's exact test showed significant differences (1 year: p = 0.014, 2 year: p = 0.008, 3 year: p = 0.008).

Conclusion

Regarding patients with previous IS who had poor response to thrombolytics and anticoagulants, LAAO could effectively decrease recurrence of IS and incidence of systemic embolism and prolong RFS of patients. LAAO was, therefore, an alternative for patients with high IS recurrence risk.