Cor triatriatum may exist as a stand alone abnormality [1], or may be associated with other congenital heart malformations, some caused by absent or abnormal conotruncal inversion, some by persistence of embryonic structures, some by lack of atrial, ventricular or atrioventricular septum development [2]. Some associations, such as between cor triatriatum and a bicuspid aortic valve, may be harder to explain as a consequence of a single event in embryonic development and may occur as separate entities [3]. Other left heart obstructive lesions may also exist [4].

The patient presents for various reasons, depending on heart anatomy and function. If the abnormality is left- sided, symptoms are similar to those induced by mitral stenosis, appear sooner and are more dramatic if the opening in the accessory membrane separating the true left atrium from the supranumerary chamber is smaller. If this communication is large, the patient may be asymptomatic and diagnosis is made on an echocardiography examination performed for other reasons. If complaints do exist, they consist of hemoptysis, orthopnea and signs of left heart failure: dyspnea on exercise and asthenia. Children with a restrictive membrane defect fail to thrive or may present with severe neonatal respiratory distress [5] due to the pressure gradient between the true and accessory atrial chambers. In cor triatriatum dexter, right heart failure signs appear first and consist of edema, ascites, painful hepatomegaly and jaundice. Rhythm abnormalities like atrial fibrillation or tachycardia may coexist in both forms. Physical examination of a cor triatriatum sinister patient may reveal further abnormalities: signs of systemic embolism, pulmonary rales or pleural effusion, heart murmurs, tachypnea and respiratory distress. In a right sided abnormality, the physician may find elevated jugular venous pressure, tricuspid regurgitation and right ventricular heave. Pulmonary hypertension may also be present. Adults become symptomatic if the membrane within the left atrium becomes calcified [6] or during sustained effort, such as labor [7] [8].

• Mediastinal Lymphadenopathy

  To our knowledge, this case represents the first pediatric example of extensive mediastinal lymphadenopathy mimicking the appearance of a malignant process as a result of severe pulmonary venous hypertension. 2012 Wiley Periodicals, Inc. [ncbi.nlm.nih.gov]

• Congestive Heart Failure

  We present here a 6-year old boy who was diagnosed with cor triatriatum sinister, initially showing symptoms similar to mitral valve stenosis and congestive heart failure, and who underwent subsequent surgical correction using a left atrial approach. [ncbi.nlm.nih.gov]

  If the communicating orifice is small, the patient is critically ill and may succumb at a young age (usually during infancy) to congestive heart failure and pulmonary edema. [en.wikipedia.org]

  Case presentation A 33 - year old woman presented to our cardiology service with signs and symptoms of congestive heart failure. [cardiothoracicsurgery.biomedcentral.com]

  We recommend anticoagulation as secondary prevention therapy in adult patients with ischemic stroke associated with cor triatriatum sinistrum and no congestive heart failure syndrome. [healthcare-bulletin.com]

• Lymphadenopathy

  To our knowledge, this case represents the first pediatric example of extensive mediastinal lymphadenopathy mimicking the appearance of a malignant process as a result of severe pulmonary venous hypertension. 2012 Wiley Periodicals, Inc. [ncbi.nlm.nih.gov]

  On examination, he was pale, afebrile, anicteric, no significant lymphadenopathy, no pedal edema. Pulse was 84 beat/min, large volume, regular, and collapsing. His jugular venous pressure was not elevated. [nigjcardiol.org]

• Pleural Effusion

  Thoracic radiography may reveal pulmonary congestion and pleural effusion and cardiomegaly due to enlarged atria and dilated pulmonary arteries. [symptoma.com]

  The findings include: Pulmonary congestion with haziness (Kerley B-lines) Ground glass appearance of acute pulmonary edema Prominent pulmonary vessels Pleural effusion Left atrial enlargement Cardiomegaly Electrocardiography (ECG) ECG findings are non-specific [statpearls.com]

  Other symptoms may include palpitation, effort intolerance, and features suggestive of systemic thromboembolism. [20] Physical findings include murmur, pulmonary congestion, tachypnea, respiratory distress, pulmonary rales, pleural effusion, hypoxemia [nigjcardiol.org]

• Failure to Thrive

  We present a rare case of cor triatriatum sinistrum in a 6-month-old female infant who was presented with cyanosis and failure to thrive. [jctm.mums.ac.ir]

  Every patient who has palpitation and failure to thrive should have thorough cardiologic evaluation to find out the rare cardiac abnormalities and managed accordingly. [ibimapublishing.com]

  Typical presentation includes dyspnea, heart failure, and failure to thrive 5. [radiopaedia.org]

• Jaundice

  In cor triatriatum dexter, right heart failure signs appear first and consist of edema, ascites, painful hepatomegaly and jaundice. Rhythm abnormalities like atrial fibrillation or tachycardia may coexist in both forms. [symptoma.com]

• Heart Disease

  Cor triatriatum is a rare congenital anomaly known to be associated with other inherited heart diseases. [ncbi.nlm.nih.gov]

  disease (CCHD) screening utilizes pulse oximetry to detect heart disease in the neonatal period. [jcnonweb.com]

• Heart Failure

  However, features of systemic embolization, heart failure, atrial fibrillation, cyanosis, cardiac asthma, syncope, and sudden cardiac arrest have also been reported in the literature. [ncbi.nlm.nih.gov]

  Second, it may present as right heart failure. [jiaecho.org]

  If complaints do exist, they consist of hemoptysis, orthopnea and signs of left heart failure: dyspnea on exercise and asthenia. [symptoma.com]

• Chorea

  Cor triatriatum sinister, not mitral stenosis, in an adult with previous Sydenham's chorea: diagnosis and preoperative assessment by cross sectional echocardiography. Br Heart J. 1992 Jul. 68(1):9-11. [Medline]. [Full Text]. [emedicine.medscape.com]

  Cor triatriatum sinister, not mitral stenosis, in an adult with previous Sydenham's chorea: Diagnosis and preoperative assessment by cross sectional echocardiography. Br Heart J 1992;68:9-11. 7. Bartel T, Müller S, Erbel R. [annals.in]

• Spastic Quadriplegia

  Reduced preload because of CTD with spastic quadriplegia that prevented physical exertion is believed to have facilitated this patient's unusually long survival. 2012 Wiley Periodicals, Inc. [ncbi.nlm.nih.gov]

  Finally, forth patient was a 48-year-old man with congenital spastic quadriplegia, who had a combination of uncorrected tetralogy of Fallot and CTD. [16] He underwent an emergent appendectomy, which was followed by a prolonged stay in the intensive care [annals.in]

• Quadriplegia

  Reduced preload because of CTD with spastic quadriplegia that prevented physical exertion is believed to have facilitated this patient's unusually long survival. 2012 Wiley Periodicals, Inc. [ncbi.nlm.nih.gov]

  Finally, forth patient was a 48-year-old man with congenital spastic quadriplegia, who had a combination of uncorrected tetralogy of Fallot and CTD. [16] He underwent an emergent appendectomy, which was followed by a prolonged stay in the intensive care [annals.in]

• Asthenia

  If complaints do exist, they consist of hemoptysis, orthopnea and signs of left heart failure: dyspnea on exercise and asthenia. [symptoma.com]

Hypoxemia may be noticed in a newborn with severe respiratory distress caused by cor triatriatum. The electrocardiogram may be normal or it may show signs of right ventricular hypertrophy and strain, right axis deviation, left, right or biatrial enlargement and supraventricular arrhythmia. Thoracic radiography may reveal pulmonary congestion and pleural effusion and cardiomegaly due to enlarged atria and dilated pulmonary arteries. Heart catheterization shows increased left atrial, right atrial, ventricular and pulmonary artery pressures, that become worse during exercise [9], with possible systemic hypotension and a gradient across the accessory membrane. Cardiac computer tomography and magnetic resonance are used when diagnosis is uncertain [10], but echocardiography usually elucidates the diagnosis [11], the morphology of the atria and venous return and the hemodynamic consequences of the abnormality. If a restrictive opening in the accessory membrane exists, the flow across it will be found both during the systole and diastole [12]. Three dimensional fully-sampled matrix array transoesophageal echocardiography (TEE) offers further information, if needed [13].

• Mediastinal Mass

  Author information 1 Department of Cardiology, Nationwide Children's Hospital, Columbus, Ohio, USA. [email protected] Abstract This report describes a patient with a superior mediastinal mass and extensive intrathoracic lymphadenopathy [ncbi.nlm.nih.gov]

• Superior Mediastinal Mass

  Author information 1 Department of Cardiology, Nationwide Children's Hospital, Columbus, Ohio, USA. [email protected] Abstract This report describes a patient with a superior mediastinal mass and extensive intrathoracic lymphadenopathy [ncbi.nlm.nih.gov]

• Pleural Effusion

  Thoracic radiography may reveal pulmonary congestion and pleural effusion and cardiomegaly due to enlarged atria and dilated pulmonary arteries. [symptoma.com]

  The findings include: Pulmonary congestion with haziness (Kerley B-lines) Ground glass appearance of acute pulmonary edema Prominent pulmonary vessels Pleural effusion Left atrial enlargement Cardiomegaly Electrocardiography (ECG) ECG findings are non-specific [statpearls.com]

  Other symptoms may include palpitation, effort intolerance, and features suggestive of systemic thromboembolism. [20] Physical findings include murmur, pulmonary congestion, tachypnea, respiratory distress, pulmonary rales, pleural effusion, hypoxemia [nigjcardiol.org]

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