There are a variety of clinical manifestations of<unk> . Acute symptoms can be due to both cardiac and non-cardiac defects. Cyanosis or blue skin coloration, primarily affecting the lips and fingernails, can indicate a systemic or circulatory issue. Poor feeding, failure to thrive, and rapid shallow breathing may also be observed due to poor circulation. Upon examination, arrhythmia and heart murmur may raise further suspicion of a cardiac abnormality. Non-cardiac symptoms include impairments of the liver and gastrointestinal tract. Biliary atresia, or inflammation and destruction of the bile ducts, may lead to jaundice. Vomiting and swelling of the abdominal region are features that suggest improper positioning of the intestines. Poor positioning of the intestine also makes it more prone to blockage, which can result in numerous chronic health issues. Asplenia and polysplenia are also possible features of heterotaxy syndrome. Due to abnormal cardiac development, patients with<unk>  usually develop right atrial isomerism consisting of two bilaterally paired right atria, or left atrial isomerism consisting of two bilaterally paired left atria. Clinical features and symptoms can vary dependent upon assignment of left versus right atrial isomerism. In either instance, the apex of the heart will be poorly positioned, which should alert a clinician of the likelihood of atrial isomerism. It is estimated that 5-10% of isomeric patients have mesocardia, in which the heart is positioned at the center of the thorax, 25-50% have dextrocardia, in which the apex of the heart is pointed toward the right side of the thorax, and 50 - 70% have levocardia, in which the apex of the heart is pointed toward the left side of the thorax. Right atrial appendage isomerism Right atrial appendage isomerism, also called right atrial isomerism, is a cardiac development defect in which the heart has bilateral right atria and atrial attachments in the muscle wall, as opposed to the normal right atrium and left atrium. In right atrial isomerism, the pulmonary blood oxygen tract is damaged due to right-left shunting of blood. In addition, the atrial septum which distinguishes the 2 atria is absent. These impairments, in addition to congestion in the pulmonary tract, allows deoxygenated blood to mix with oxygenated blood, contributing to cyanosis and possible respiratory distress. Poor systemic circulation also results due to improper positioning of the aorta. Left atrial appendage isomerism Left atrial appendage isomerism, also called left atrial isomerism, is a cardiac development defect in which the heart has 2 bilateral left atria and atrial appendages in the muscle wall. Left atrial isomerism can have varied clinical manifestations, including a later onset of symptoms. Heart failure is often a concern because the inferior vena cava is disrupted due to the inappropriate morphology of the left ventricle to support the vena cava. Conductive nodes and tissues Abnormal development of the heart results in impaired doubles of conductive nodes, as well as faulty electrical fibers throughout the ventricles. Individuals with right atrial isomerism develop 2 sinoatrial nodes, as they have 2 mirrored right atria, whereas those with left atrial isomerism fail to develop a sinus node at all. Thus, patients with left atrial isomerism are more likely to experience atrial fibrillation, or irregular rapid heart beat, and abnormal heart rhythm, known as atrial flutter. Development of the atrioventricular node and bundle of His largely depends on physiological looping of the ventricles. Abnormal looping of the ventricles contributes to arrhythmia and heart block in fetuses. Bronchial tree and lungs Isomerism of the bronchial tree is not typically damaging and presents no significant clinical complications. Pulmonary valve stenosis results in issues of blood flow to the lungs. Abdominal organs Abdominal organs, including the liver, stomach, intestinal tract, and spleen may be randomly arranged throughout the left-right axis of the body. Distribution of these organs largely dictates treatment, clinical outcomes, and further evaluation. The liver is typically symmetrical across the left-right axis in patients with<unk> , which is abnormal. A majority of left atrial isomeric patients have defects throughout the biliary tree, which is responsible for bile production, even when the gall bladder is functional and morphologically normal. This biliary atresia can lead to acute problems such as nutrient malabsorption, pale stools, dark urine, and abdominal swelling. If this condition continues without proper treatment, cirrhosis and liver failure become a major concern. Biliary atresia is not usually observed in patients with right atrial isomerism. Random positioning of the stomach is often one of the first signals of<unk>  upon examination. Malrotation of the entire intestinal tract, or improper folding and bulging of the stomach and intestines, results in bowel obstruction. This impairment leads to vomiting, abdominal distention, mucus and blood in the stool. Patients may also experience abdominal pain. Intestinal malrotation is more commonly identified in patients with right atrial isomerism than in those with left atrial isomerism. Isomeric patients often experience disruptions to splenic development during embryogenesis, resulting in an overall lack a spleen (asplenia) or development of many spleens (polysplenia). Asplenia is most often observed in patients with right atrial isomerism. Polysplenia results in 90% of patients with left atrial isomerism. Although they have many spleens, each is usually ineffective resulting in functional asplenia. Rarely, left atrial isomeric patients have a single, normal, functional spleen. Patients lacking a functional spleen are in danger of sepsis and must be monitored.
Situs ambiguus
Situs inversus
Pulmonary agenesis
Double aortic arch
Pulmonary atresia
Gastroschisis
Diaschisis
Cranioschisis