Incidental Finding of Incomplete Cor Triatriatum Dextrum During 2nd Trimester of Pregnancy

Background: Cor triatriatum sinistrum is a type of congenital heart defect that occurs due to the left atrium being divided into two chambers by a fibromuscular septum. An even rarer subsection of this is cor triatriatum dextrum, in which the fibromuscular septum fully divides the right atrium. Case presentation: We present a patient with intermittent palpitations, chest pressure, and lightheadedness without syncope related to her cor triatriatum dextrum exacerbated by her pregnancy status. Without any prior history of congenital heart defects or pertinent family history, this seemingly health female prior to her pregnancy likely revealed and exacerbated her symptoms and lead to the diagnosis. Conclusions: Treatment in the setting of an asymptomatic presentation of a pregnant patient with history of cor triatriatum remains unclear. Many physicians elect close follow up to monitor for development of symptoms. In symptomatic cases, rate control, thromboembolic prophylaxis, and hemodynamic stabilization are mainstays of treatment. This unique presentation in a rare patient population furthers literature and gives a perspective on pregnancy and structural heart disease like cor triatriatum.