Left atrial appendage membrane is a rare anomaly. Its implications on clinical course are unknown. We report the first paediatric case in association with a congenital heart disease.

We present a rare case of an asymptomatic giant congenital left atrial appendage aneurysm in a 19-year-old girl. We believe this is the largest congenital left atrial appendage aneurysm reported without any symptom.

A complex case of congenital heart disease is presented which features isomerism of the left atrial appendages combined with bronchoatrial discordance and an anteriorly placed non-interrupted inferior caval vein draining to the left-sided atrium. This combination of anomalies has, as far as we are aware, not been described before. It emphasizes the importance of direct confirmation of atrial arrangement by atrial angiography or transesophageal echocardiography.

A 16-year-old girl with no previous cardiac problems presented to the casualty with septic shock. Investigations revealed endocarditis involving the mitral valve. At the time of surgery, she was noted to have a large left atrial appendage herniating into the left pleural cavity due to partial absence of the pericardium. Complete or partial absence of the pericardium is an uncommon congenital anomaly. Though various complications and presentations are reported, it has not been identified as a risk factor for endocarditis. We discuss the possible mechanism, and need for prophylaxis against endocarditis, in patients with absence of the pericardium.