Rare Cardiology News

Disease Profile

Cor triatriatum sinister

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Cor triatriatum sinistrum; Divided left atrium


Congenital and Genetic Diseases; Heart Diseases


Cor triatriatum sinister (CTS) results when the left atrium is divided into two compartments by a membrane. The membrane can vary in size and shape and may have one or more openings.[1] Severe cases of cor triatriatum sinister usually present in infancy and are often associated with other heart defects. In less severe cases, the diagnosis may not be made until later in life.[1][2] The specific symptoms depend on the degree to which the membrane obstructs the flow of blood and whether or not there are additional heart defects.[1][2] Symptoms may range from mild shortness of breath during exercise to signs of heart failure and lung congestion. Some people with CTS may not have symptoms.[1][2] Treatment varies according to the severity of the symptoms. For symptomatic patients, surgery is generally considered the definitive course of therapy.[2][3]


Treatment for cor triatriatum sinister varies depending on the symptoms. For patients with milder cases who are diagnosed much later in life, surgery may not be needed. [2] In symptomatic patients, treatment may include diuretics, medications to change the force of the heart's contractions (inotropic medications), and medications to prevent clots from forming (anticoagulant therapy).[2][1] Surgery, however, is considered the definitive therapy for those who are symptomatic.[2][3] The overall life expectancy after surgical repair is expected to be similar to that for the general population.[4]


Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Providing General Support

    Learn more

    These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

    Where to Start

    • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

      In-Depth Information

      • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
      • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
      • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
      • PubMed is a searchable database of medical literature and lists journal articles that discuss Cor triatriatum sinister. Click on the link to view a sample search on this topic.


        1. Shirani, Jamshid. Cor Triatriatum. Medscape Reference. December 18, 2014; https://emedicine.medscape.com/article/154168-overview. Accessed 11/11/2015.
        2. Strickland, PT et al.. Cor triatriatum sinister: a patient, a review, and some unique findings.. Echocardiography. July, 2014; 31(6):790-4. https://www.ncbi.nlm.nih.gov/pubmed/?term=24649916. Accessed 11/11/2015.
        3. Saxena, P et al.. Surgical repair of cor triatriatum sinister: the Mayo Clinic 50-year experience. Annals of Thoracic Surgery. May, 2014; 97(5):1659-63. https://www.ncbi.nlm.nih.gov/pubmed/?term=24630764. Accessed 11/11/2015.
        4. Capdeville, Michelle, et al.. Cor Triatriatum Sinister Presenting in Adulthood. Journal of Cardiothoracic and Vascular Anesthesia. April, 2014; 28(2):408-16. https://www.ncbi.nlm.nih.gov/pubmed/24355595. Accessed 11/11/2015.

        Rare Cardiology News