Background We performed a systematic review of cor triatriatum sinistrum (CTS) diagnosed in adults. The aim of this review was to describe the clinical presentation, natural history and management of this congenital heart disease.

Methods A PubMed literature search for ‘cor triatriatum sinistrum’ published since 2005 was performed. Included patients were divided into those with and without obstructive membrane physiology. The clinical course differences were compared.

Results A total of 171 published cases were included. The median age at diagnosis was 43 years (IQR, 30–60). Obstructive membrane physiology was observed in 70 (41%), and this patient group was younger at presentation (median age 39 (IQR, 28–52) vs 50 years (IQR, 32–64), p=0.003). Patients with obstructive membrane more frequently had associated cardiac defects (58.6% vs 42.4%, p=0.039). Overall, the most frequent clinical symptom was atrial fibrillation, as this was present in 56 (32.8%) of all patients. CTS-related symptoms were more frequent in patients with obstructive membrane: congestive heart failure (44.3% vs 15.2%, p<0.001), pulmonary hypertension (27.1% vs 6.1%, p<0.001), haemorrhage (8.6% vs 0%, p=0.004) and infections manifestation (8.6% vs 0%, p=0.004).

A total of 71 (41.5%) patients with CTS required interventional treatment, mainly within patients with the obstructive membrane (86.8% vs 12.6%, p<0.001).

Conclusion The natural history of CTS most often manifests with symptoms of congestive heart failure. Patients with obstructive membrane most often have associated cardiac defects and higher risk for infections and haemorrhage. The interventional treatment of CTS remains the first choice for obstructive membrane.