Cor Triatriatum Seoul National University Hospital Department of Thoracic & Cardiovascular Surgery

Cor Triatriatum 1. Definition 2. History A rare congenital cardiac anomaly in which the pulmonary veins enter a proximal left atrial chamber separated from the distal left atrial chamber by a diaphragm in which there are one ore more restrictive ostia. * Cor triatriatum sinister, Cor triatriatum dexter 2. History Church : 1st description in 1868 Borst : The term of cor triatriatum in 1905 Miller et al : Angiographic diagnosis in 1964 Ostman-Smith : Description by Echo. In 1984 Vineberg & Gialloreto : 1st surgical correction in 1956

Cor Triatriatum Pathophysiology Persistence of a common pulmonary vein forms an accessory left atrial chamber that communicates with the true left atrium via the restrictive fibromuscular diaphragm. Pulmonary venous return is restricted, resulting in pulmonary venous congestion and hypertension, right ventricular hypertrophy, and congestive heart failure.

Drawing of Cor Triatriatum

Cor Triatriatum 3. Types 1. Prevalence 2. Embryology 0.1-0.4% of CHD 1) Communication with LA (classic) a. With intact atrial septum b. CPVC communicating with RA c. Atrial defect into lower chamber 2) No communication with LA (imperforate diaphragm) Drainage into RA Drainage into coronary sinus Drainage into systemic vein 1. Prevalence 0.1-0.4% of CHD Equal frequency in both sex Isolated : 33-50% 2. Embryology * Dorsal eventration of common atrium (CPV), enlarges to join pulmonary segment of splanchnic plexus. * Malformations result from abnormal growth or regression of common pulmonary vein.

Pulmonary Venous Connection Patterns of malformation 1. Total anomalous pulmonary venous drainage The common pulmonary vein fails to establish communication with pulmonary venous plexus, then pulmonary vein to systemic venous connection will persist. 2. Atresia of common pulmonary vein The common pulmonary vein is obliterated after the venous channels have disappeared. 3. Cor triatriatum sinister After connection between atrium and confluence of pulmonary veins accomplished by common pulmonary vein, abnormal incorporation into left atrium causes stenosis or obstruction.

Morphology of Cor Triatriatum 1. Classical morphology * Thick common pulmonary vein chamber & thin distal LA chamber * One or more openings, thick and fibromuscular, or tubular * RV enlarged due to Lt. to Rt. shunt * LV usually normal or small * Foramen ovale usually patent and stretched * PAPVR may coexist 2. Relationship to a left SVC * Frequently than other type of CHD, * Theory of impingement of SVC on developing LA 3. Associated anomalies * PAPVR, TAPVR * Unroofed coronary sinus with Lt SVC * VSD, COA, AV canal, TOF

Major Types of Cor Triatriatum

Cor Triatriatum Diaphragm LV LV Diaphragm

Clinical Features & Diagnosis 1. Patients with small opening present with evidence of LCO ( pallor, tachypnea, poor peripheral pulse, growth failure with pulmonary venous hypertension) 2. When there is associated Lt. to Rt. Shunt, evidence of pulmonary overcirculation and venous obstruction may be present in X-ray, and right ventricular enlargement is prominent 3. Signs and symptoms of pulmonary venous hypertension 4. Diagnosis can be suspected by echocardiography, MRI

Cor Triatriatum Natural History 1. Rare congenital cardiac anomaly 2. Natural history depends on effective size of hole in the partition between the common pulmonary venous chamber and left atrium 3. Mostly, the hole is severely restrictive and about 75% die in infancy without treatment 4. When communicates with right atrium through ASD, the prognosis is better ( depend on the size of hole).

Techniques of Operation 1. Typical cor triatriatum Diaphragm is excised to make an opening as large as possible and the opening in the atrial septum closed. 2. Atypical cor triatriatum Combination of typical repair, and anomalous pulmonary venous connection.

Operative View of Cor Triatriatum Excised daiphragm Diaphragm Opening

Cor Triatriatum Operative Results 1. Early death Uncommon, but occurs in critically ill with inadquate myocardial management 2. Survival Approaches that of general population and good functional result 3. Complications * Restenosis due to inadequate resection * Pulmonary vein stenosis

Indications for Operation 1. Urgent indication for restrictive aperture 2. Operation is necessary in the 1st year of life 3. In older patients with chronic symptom, operation is also urgently indicated. 4. In complex cor triatriatum, operation is indicated on an urgent basis.

Cor Triatriatum Dexter 1. Definition A rather unusual congenital cardiac malformation in which a persistent right valve of sinus venosus subdivides right atrium 2. History Rokitansky : 1st description in 1875 3. Embryology Right horn of sinus venosus is incorporated into right atrium, giving rise to orifice of the SVC and IVC. At one point the right valve of sinus venosus nearly divides right atrium, the valve regresses and moves caudally, leaving the crista terminalis, and the valve of IVC (Eustachian) and coronary sinus (Thebesian).

Cor Triatriatum Dexter Clinical Features 1. Pathology Some minor degree of septation of right atrium by the remnant of right valve of sinus venous is well tolerated, and a prominent Eustachian valve is common finding. 2. Clinical presentation * Somewhat variable * Asymptomatic in vast majority * Recurrent supraventricular tachycardia * Right heart failure in symptomatic patients * Cyanosis in the presence of ASD