An uncommon cardiovascular abnormality: Case report of core triatriatum associated with persistent left superior vena cava and coronary sinus dilation

Abstract

Cor triatriatum is an uncommon cardiac defect that occurs in 0.1-0.4% of congenital heart disease patients. It is characterized by a fibromuscular membrane separating the left (sinister) or the right (Dexter) atriums in tow chambers. The disease is usually discovered accidently in late childhood, usually as a result of a moderate form of this condition type. We discuss the case of a 14-year-old girl who had been experiencing exertional dyspnea and palpitations for about a year. She was referred to our hospital for assessment after an initial echocardiogram at another hospital revealed a mass around the left atrium. Repeated echocardiography at our institution revealed dilated coronary sinus, confusing the diagnosis. The left atrium was dilated and divided into 2 chambers by a thin membrane with an elevated pressure gradient between the 2 chambers. Cardiac CT and MRI confirmed the diagnosis of cor triatriatum sinister (CTS) with concomitant persisting left superior vena cava. Because of her symptoms, she was started medical treatment and referred for surgical evaluation. Cor triatriatum sinister (CTS) is frequently accompanied with atrial septal abnormalities and enlarged coronary sinus caused by a persistent left superior vena cava, as demonstrated in our case. The management of cor triatriatum sinister (CTS) is determined by the severity of the symptoms. Asymptomatic individuals with no pressure gradient do not require therapy; however, significant membrane obstruction may require surgical removal, which typically leads to positive short- and long-term outcomes.

Keywords: Case report; Congenital heart disease; Cor triatriatum sinister; Dilated coronary sinus; Persistent left superior vena cava.

Fig. 1

Transthoracic Echocardiography Apical 4 chambers view showing dilated coronary sinus (Arrow) and fibromuscular membrane (curved arrow) with internal fenestration and turbulent flow (star) dividing the left atrium into 2 chambers, a proximal chamber (thick arrow) containing the pulmonary vines, and a distal chamber “true” left atrium (thin arrow) containing the left atrial appendage.

Fig. 2

Transthoracic Echocardiography Apical 4 chambers view showing high pressure gradient across the membrane (34mmHg) and high pulmonary artery systolic pressure of 57 mmHG and mild tricuspid regurgitation.

Fig. 3

Two images of cardiac CT scans, axial and oblique sagittal views, show a fibromuscular membrane (curved arrow) with internal fenestration (star) and a focus of calcification (thinnest arrow), dividing the left atrium into 2 chambers, a proximal chamber (thick arrow) containing the pulmonary vines (arrowhead), and a distal chamber “true” left atrium (thin arrow) containing the left atrial appendage.

Fig. 4

Two images of 3D reconstruction cardiac CT scans, show a fibromuscular membrane (curved arrow), with internal fenestration (star), dividing the left atrium into 2 chambers, a proximal chamber (thick arrow) containing the pulmonary veins (arrowhead), and a distal chamber “true” left atrium (thin arrow) containing the left atrial appendage.

Fig. 5

Two images of cardiac CT scans, axial and coronal views, show superior vena cava duplication (arrows).

Fig. 6

Two images of cardiac CT scans, oblique sagittal views, show persistent left-sided SVC (arrow), draining through the coronary sinus (arrowhead) into the right atrium.

Fig. 7

(A) 3D reconstruction cardiac CT scan shows double SVC, persistent left-sided SVC (arrow), and normal right-sided SVC (arrowhead). (B) 3D reconstruction cardiac CT scan shows persistent left-sided SVC (arrow) draining through the coronary sinus into the right atrium (arrowhead).

Fig. 8

Two images of cardiac MRI, balanced turbo field echo (BTFE) sequence, axial and sagittal views, show a fibromuscular membrane (curved arrow) with internal fenestration (star), dividing the left atrium into 2 chambers, a proximal chamber (thick arrow) containing the pulmonary vines (arrowhead), and a distal chamber “true” left atrium (thin arrow) containing the left atrial appendage.