Cor triatriatum


XC: anomalous upper chamber
  • Congenital anomaly: heart with three atria
  • Either LA or RA can be divided into 2 compartments (cor triatriatum sinistrum or cor triatriatum dextrum)
  • Can be associated with other congenital syndromes including tetralogy of Fallot, double outlet RV, coarctation of the aorta, VSD, AV septal defect
  • 0.1-0.4% incidence in USA

Clinical Features

  • Sinistrum variant most associated with other congenital cardiovascular defects in symptomatic infants
  • Can be incidental finding in adults as either isolated finding or in association with PFO, ASD, persistent left superior vena cava
  • Symptoms depend on size of opening in accessory membrane between the atria
  • Symptoms include dyspnea on exertion, orthopnea, easy fatiguability, low exercise tolerance, palpitations
  • Increased risk of thrombus formation in LA
  • Murmur
  • Elevated JVD
  • Hepatomegaly
  • Ascites
  • Peripheral edema

Differential Diagnosis

Congenital Heart Disease Types


  • Initial workup may include:
    • ECG: Atrial premature complexes, Left or Right atrial abnormalities, Right axis deviation, Right heart strain
    • CXR
    • Echocardiography
    • Right heart cath


  • As associated with major cyanotic or acyanotic congenital heart lesions, mortality can be up to 75% in untreated symptomatic infants
  • Treat increased pulmonary vascular resistance, heart failure
  • Inotropic agents (eg, dopamine, dobutamine), diuretics
  • Manage hypoxia, fluid status, rate in afib
  • DVT/PE prophylaxis
    • Cardiac surgery consultation


See Also

External Links


  1. Knipe K et al. Cyanotic congenital heart diseases. Radiopaedia.