Presentation
Increasing shortness of breath for the last 1.5 years.
Patient Data
A thin funnel-shaped membrane divides the left atrium into a larger posterior chamber and a smaller anterior chamber. The pulmonary veins drain into the larger posterior chamber. An inferiorly located 1.4 cm fenestration connects the 2 chambers.
Case Discussion
Cor triatriatum accounts for about 0.1% of congenital heart defects. This case is unusual: the patient was asymptomatic until they were nearly 50 years old, most patients with this anomaly die before reaching 2 years of age. The late presentation in this patient is likely secondary to the relatively large fenestration between the 2 left atrial chambers.