Dextrocardia

Dextrocardia
Classification and external resources
Chest X ray of a person with dextrocardia situs inversus showing the cardiac apex facing the right
ICD-10	Q24.0
ICD-9	746.87
DiseasesDB	3617
MedlinePlus	007326
MeSH	C14.240.400.280

Dextrocardia is a congenital defect in which the heart is situated on the right side of the body. There are two main types of dextrocardia: dextrocardia of embryonic arrest (also known as isolated dextrocardia^{[citation needed]}) and dextrocardia situs inversus. Dextrocardia situs inversus is further divided.

Dextrocardia of embryonic arrest

In this form of dextrocardia, the heart is simply placed farther right in the thorax than is normal. It is commonly associated with severe defects of the heart and related abnormalities including pulmonary hypoplasia.^[1]

Dextrocardia situs inversus

Dextrocardia situs inversus refers to the heart being a mirror image situated on the right side. For all visceral organs to be mirrored, the correct term is dextrocardia situs inversus totalis.

Dextrocardia is believed to occur in approximately 1 in 12,000 people.^[2]

Although statistically people with dextrocardia situs inversus do not have any medical problems from the disorder, they may be prone to a number of bowel, esophageal, bronchial and cardiovascular disorders (such as double outlet right ventricle, endocardial cushion defect and pulmonary stenosis). ^[3] Certain cardiovascular and pulmonary disorders related to dextrocardia can be life-threatening if left unchecked (see ref).

Kartagener syndrome may also be present in patients with dextrocardia situs inversus but also involves mirrored positioning of major internal organs and may include male infertility. ^[4]

Diagnosis

Medical diagnosis of the two forms of congenital dextrocardia can be made by ECG^[1] or imaging.

Technical dextrocardia

Technical dextrocardia refers to an ECG reading that has no basis in the patient's anatomy. This apparent presentation of dextrocardia is caused usually by the technician inadvertently swapping the limb leads on a 12 lead ECG. Usually this would show as an extreme axis deviation.

Management

ECG leads must be placed in reversed positions on a person with dextrocardia. In addition, when defibrillating someone with dextrocardia, the pads should be placed in reverse positions. ^[5] That is, instead of upper right and lower left, pads should be placed upper left and lower right. ^[6]

References

External links

• MedEd at Loyola GrossAnatomy/thorax0/Heart_Development/Dextrocardia.html
• Overview at rch.org.au
• Dextrocardia at NIH's Office of Rare Diseases
• Dextrocardia with situs inversus at NIH's Office of Rare Diseases