Interrupted aortic arch is a very rare
heart defect
A congenital heart defect (CHD), also known as a congenital heart anomaly, congenital cardiovascular malformation, and congenital heart disease, is a defect in the structure of the heart or great vessels that is present at birth. A congenital h ...
(affecting 3 per million live births)
in which the
aorta
The aorta ( ; : aortas or aortae) is the main and largest artery in the human body, originating from the Ventricle (heart), left ventricle of the heart, branching upwards immediately after, and extending down to the abdomen, where it splits at ...
is not completely developed. There is a gap between the ascending and descending
thoracic aorta
The thoracic aorta is a part of the aorta located in the thorax. It is a continuation of the aortic arch. It is located within the posterior mediastinal cavity, but frequently bulges into the left pleural cavity. The descending thoracic aorta be ...
. In a sense it is the complete form of a
coarctation of the aorta
Coarctation of the aorta (CoA) is a congenital condition whereby the aorta is narrow, usually in the area where the ductus arteriosus ( ligamentum arteriosum after regression) inserts. The word ''coarctation'' means "pressing or drawing toget ...
. 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
DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent ...
.
Signs and symptoms
Patients with an interrupted aortic arch usually have symptoms from birth, with nearly all presenting symptoms within two weeks (when the
ductus arteriosus
The ductus arteriosus, also called the ductus Botalli, named after the Italian physiologist Leonardo Botallo, is a blood vessel in the developing fetus connecting the trunk of the pulmonary artery to the proximal descending aorta. It allows mos ...
is usually closed).
Causes
It is thought that an interrupted aortic arch occurs through excessive
apoptosis
Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...
in the developing, embryonic aorta.
Around 50% of patients have
DiGeorge syndrome
DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent ...
.
Diagnosis
It can be diagnosed with a standard
echocardiogram
Echocardiography, also known as cardiac ultrasound, is the use of ultrasound to examine the heart. It is a type of medical imaging, using standard ultrasound or Doppler ultrasound. The visual image formed using this technique is called an echo ...
.
An echocardiogram can also aid in classifying the type of defect.
The diagnosis can also be made prior to birth via
ultrasound
Ultrasound is sound with frequency, frequencies greater than 20 Hertz, kilohertz. This frequency is the approximate upper audible hearing range, limit of human hearing in healthy young adults. The physical principles of acoustic waves apply ...
.
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