Dextrocardia (from Latin ''dextro'', meaning "right hand side," and Greek ''kardia'', meaning "heart") is a rare

congenital condition A birth defect, also known as a congenital disorder, is an abnormal condition that is present at childbirth, birth regardless of its cause. Birth defects may result in disability, disabilities that may be physical disability, physical, intellect ...

in which the apex of the

heart The heart is a muscular organ found in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon diox ...

is located on the right side of the body, rather than the more typical placement towards the left. There are two main types of dextrocardia: dextrocardia of embryonic arrest (also known as isolated dextrocardia) and dextrocardia ''

situs inversus Situs inversus (also called situs transversus or oppositus) is a congenital condition in which the major visceral organs are reversed or mirrored from their normal positions. The normal arrangement of internal organs is known as situs solitus. A ...

''. Dextrocardia ''situs inversus'' is further divided.

Classification

Dextrocardia of embryonic arrest

In this form of dextrocardia, the heart is simply placed further right in the

thorax The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the ...

than is normal. It is commonly associated with severe defects of the heart and related abnormalities including

pulmonary hypoplasia Pulmonary hypoplasia is incomplete development of the lungs, resulting in an abnormally low number or size of bronchopulmonary segments or alveoli. A congenital malformation, it most often occurs secondary to other fetal abnormalities that ...

Dextrocardia situs solitus

Dextrocardia refers to a heart positioned in the right side of the chest. Situs solitus describes viscera that are in the normal position, with the stomach on the left side.

Dextrocardia situs inversus

Dextrocardia situs inversus refers to the heart being a mirror image situated on the right side. For all

viscera In biology, an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life, an organ lies between tissue and an organ system. Tissues are formed from same type cells to act together in a ...

l organs to be mirrored, the correct term is dextrocardia situs inversus totalis. Although statistically people with dextrocardia 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). Certain cardiovascular and pulmonary disorders related to dextrocardia can be life-threatening if left unchecked. Kartagener syndrome may also be present in patients with dextrocardia but this must be in the setting of situs inversus and may include male infertility.

Dextrocardia with situs ambiguus

In contrast to dextrocardia situs inversus which is only rarely associated with congenital heart disease, dextrocardia situs ambiguus is often associated with intracardiac anomalies. Dextrocardia situs ambiguus presents a surgical challenge not per se due to associated cardiac malformation, but because achieving adequate exposure is difficult. Right sided structures such as right atrium, right ventricle and tricuspid valve are oriented posteriorly in dextrocardia situs ambiguus (in contrast to dextrocardia with situs inversus). This presents a challenge to the surgeons operating on the right-sided cardiac structures in a case of dextrocardia situs ambiguus.

Diagnosis

Medical diagnosis Medical diagnosis (abbreviated Dx, Dx, or Ds) is the process of determining which disease or condition explains a person's symptoms and signs. It is most often referred to as a diagnosis with the medical context being implicit. The information r ...

of the two forms of congenital dextrocardia can be made by ECG or imaging.

Technical dextrocardia

Technical dextrocardia refers to an ECG reading that has no basis in the patient's anatomy. This apparent presentation is typically caused by the accidental lead placement of the left and right arm electrodes. 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. That is, instead of upper right and lower left, pads should be placed upper left and lower right. When heart transplantation is required in a person with situs inversus, reconstruction of the venous pathways to accommodate a normal donor heart is a major, but not insurmountable, challenge.

Epidemiology

Dextrocardia is estimated to occur in approximately 1 in 12,019 pregnancies. A Japanese study of 1,753 fetal cardiac echocardiograms over five years revealed only two cases.

References

External links

* * {{Congenital malformations and deformations of circulatory system Congenital heart defects Rare diseases