Left atrial appendage aneurysm: a descriptive systematic review of 177 cases.

Introduction: The left atrial appendage (LAA) is a distinct structure with unique developmental and structural characteristics. The LAA is involved in the formation of intra-atrial thrombi, particularly in patients with conditions such as atrial fibrillation and mitral valve disease. Left atrial appendage aneurysms (LAAA) are rare abnormal dilations of the LAA that may cause hazardous complications. However, there are limited data on the demographic features, clinical characteristics, management modalities, and prognosis of LAAA patients. This study aimed to conduct a systematic review of the reported cases of LAAA to explore the baseline characteristics, presentation, preferred diagnostic modalities, and optimal management of LAAA.

Methods: A systematic review was conducted following the PRISMA guidelines. We performed a literature search using MEDLINE/PubMed and Google Scholar. Eligible articles published between January 1940 and November 2022 were included. The eligibility criteria included case reports and case series of LAAA in English language articles. The data extracted included information on the authors, publication year, patient characteristics, signs/symptoms, diagnostic procedures, treatments, and outcomes.

Results: We identified 177 patients with LAAA in our study. There was a slight female predominance (50.9%), and the mean age was 29.7 years. Palpitations were the most common symptom reported, followed by shortness of breath and thromboembolic events. Transthoracic and transesophageal echocardiograms were the most common modalities for investigating and diagnosing LAAA, and the mean size of the aneurysm was 7.8 (5.7-9.6) × 5.9 (5.0-6.2) cm. Surgical resection is the treatment of choice for most patients with excellent prognoses. Older age and the presence of arrhythmia were significantly associated with thrombus formation and embolic events.

Conclusion: Left atrial appendage aneurysm is a rare but potentially life-threatening heart pathology that can lead to arrhythmias and thromboembolic events. Surgical resection appears to be the primary treatment option in the current literature, and most patients show improvement or are asymptomatic after treatment. Additionally, alternative approaches, such as transcatheter closure of LAAA, ablation, and medical treatments, have been reported as viable alternatives to surgical intervention.