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.

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.

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.

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.

An aneurysm of the left atrial appendage is one of the rare but potentially hazardous heart defects. The risk of lethal complications grows with its size. To date, about 150 cases of this defect have been described in the literature. We present a case of left atrial appendage aneurysm with the deformation of the mitral valve and the left main coronary and circumflex artery, which required mitral valve annuloplasty and bifurcation stenting.

A 58-year-old man presented to our hospital complaining of shortness of breath, general weakness, dizziness during physical exertion, and fatigue. Based on the results of echocardiography, an aneurysm of the left atrium was suspected. A free-breathing real-time cine magnetic resonance imaging with electrocardiograph synchronization confirmed the diagnosis of left atrial appendage aneurysm. The patient underwent an aneurysmectomy via a median sternotomy with cardiopulmonary bypass. Intraoperative transesophageal echocardiography revealed relative mitral insufficiency that was corrected with an annuloplasty ring. Intraoperative coronary angiogram showed impaired blood flow in the left main coronary and circumflex artery and 60% stenosis. For this reason, bifurcation stenting was performed. The patient had an uneventful postoperative clinical course and was discharged from the hospital on the 10th day in a satisfactory condition.

Left atrial appendage aneurysm is a rare and dangerous heart pathology that requires surgery to prevent related complications.