Prenatal Diagnosis of a Right Atrial Appendage Aneurysm: Case Report and Review of the Literature.

 Congenital malformations of the right atrium are rare heart defects with only a few cases described prenatally. Early diagnosis of these anomalies is becoming increasingly important for proper follow-up and due to the possibility of serious complications such as supraventricular arrhythmia, thromboembolic events, and sudden death.  The atrial appendage aneurysm (AAA) is a dilatation of the atrial appendage. It is considered an extremely rare congenital anomaly. However, this condition is clinically significant because it leads to atrial arrhythmias, recurrent emboli, heart failure, and chest pain. In addition, it is possible to recognize AAA prenatally with fetal echocardiography, even if it rarely happens. However, few fetal AAA cases have been reported in the literature.  We report a case of a fetal AAA; diagnosed prenatally and with postnatal confirmation. We undertook a systematic review of studies on fetal AAA to synthesize available knowledge on diagnosing and managing this rare condition.  A total of eight studies describing 24 patients were identified and analyzed.  Despite their rarity, fetal atrial appendage aneurysms necessitate early detect on due to associated severe complications. Our findings emphasize the importance of prenatal diagnosis through fetal echocardiography and highlight the need for further research to optimize management strategies and improve outcomes for affected individuals.