Aortic arch interruption

Interrupted aortic arch is a very rare heart defect (affecting 3 per million live births) in which the aorta is not completely developed. There is a gap between the ascending and descending thoracic aorta. In a sense it is the complete form of a coarctation of the aorta. Almost all patients also have other cardiac anomalies, including a ventricular septal defect (VSD), aorto-pulmonary window, and truncus arteriosus. There are three types of interrupted aortic arch, with type B being the most common. Interrupted aortic arch (especially Type B) is often associated with DiGeorge syndrome. Interrupted aortic arch is a very rare heart defect (affecting 3 per million live births) in which the aorta is not completely developed. There is a gap between the ascending and descending thoracic aorta. In a sense it is the complete form of a coarctation of the aorta. Almost all patients also have other cardiac anomalies, including a ventricular septal defect (VSD), aorto-pulmonary window, and truncus arteriosus. There are three types of interrupted aortic arch, with type B being the most common. Interrupted aortic arch (especially Type B) is often associated with DiGeorge syndrome. It is thought that an interrupted aortic arch occurs through excessive apoptosis in the developing, embryonic aorta. It can be diagnosed with a standard echocardiogram. An echocardiogram can also aid in classifying the type of defect. The diagnosis can also be made prior to birth via ultrasound. Patients will have a loss of appetite, appear tired and weak, and exhibit rapid breathing and a rapid heart rate. If the condition progresses, the infant may turn pale, feel cold in the lower half of the body, and have a weak pulse due to insufficient blood flow. The pattern of pulse abnormalities is dependent upon the classification; e.g., for type B interrupted aortic arch, the right brachial pulse will be palpable and the left brachial and femoral pulses will be impalpable due to closure of the ductus arteriosus. Rarely, an interrupted aortic arch can be associated with an intracranial aneurysm. Signs of ischemia due to interrupted aortic arch can be separated by the organ system involved: CHARGE syndrome, a specific, rare pattern of genetic abnormalities, commonly features conotruncal and aortic arch heart defects, which can include an interrupted aortic arch. There are three primary classifications for an interrupted aortic arch, on the basis of the specific, anatomic anomaly. They are: Each class can be divided into two subgroups, based upon whether the right subclavian artery originated in a normal, anatomical position (subgroup 1) or if it originated distal to the left subclavian artery and continues behind the esophagus (subgroup 2). However, these subgroups do not affect how the disease is diagnosed or treated. If the diagnosis is made prenatally, prostaglandin E1 (PGE1) is started after birth to avoid closure of the ductus arteriosus. Prostaglandin therapy is performed via a continuous infusion, due to how quickly prostaglandins are metabolized in the body. However, the diagnosis may go undetected, delaying treatment until closure of the ductus arteriosus produces symptoms. Curative treatment consists of open heart surgery soon after birth, preferably within the first week after birth while there is a patent ductus arteriosus. Awaiting surgery, prostaglandin can be administered to keep the ductus arteriosus open, thereby allowing blood flow to the lower body. After successful treatment, the patient is monitored for the rest of their life by a specialist to ensure that problems do not occur. Failure to treat the condition yields a mortality rate of 90% at a median age of 4 days. Death occurs due to increased blood flow from the left side of the heart (oxygenated blood) to the right side (deoxygenated blood), inducing heart failure; pulmonary edema; and eventual closing of the ductus arteriosus. For an infant with an interrupted aortic arch, a patent (open) ductus arteriosus allows for blood to bypass the 'interruption,' without which blood will be unable to reach the lower half of the body. As a result, the kidneys fail and the blood becomes acidic, resulting in death.