Interrupted Aortic Arch: An Overview

Introduction:

Congenital heart diseases are the most prevalent birth defects resulting in the abnormal formation of the heart or the blood vessels next to the heart. In the United States, approximately 1 percent of births (40000) each year are affected by congenital heart diseases. There are many types of congenital heart diseases. A rare type of congenital heart disease is an interrupted aortic arch (IAA), which affects approximately 1.5 percent of congenital heart disease patients. Interrupted aortic arch is an anomaly that is often considered the most serious kind of aortic defect. This article briefly explains the Interrupted Aortic Arch and its causes, symptoms, diagnosis, treatment, possible outcomes, and differential diagnosis.

What Is an Interrupted Aortic Arch?

An interrupted aortic arch (IAA) is an uncommon heart disease that occurs when the aorta fails to develop completely. The aorta is the main artery of the heart that carries oxygen-rich blood from the heart to the rest of the body. It usually has a curved or arch form. In the interrupted aortic arch (IAA), a portion of the aorta is missing, creating a gap. This is a life-threatening situation. The child may go into shock and may die if blood does not reach any region of the body.

Aortic arch interruptions exist in three different types. They are categorized according to the location of the missing piece.

• Type A: The disruption occurs near the distal end of the left subclavian artery. This is the second most prevalent disruption, representing around 13 percent of the cases.

• Type B: The interruption is located between the left carotid artery and the left subclavian artery. Type B is the most prevalent type of interrupted aortic arch. comprising around 84 percent of the cases.

• Type C: The interruption develops between the innominate artery (an artery that originates from the aortic arch towards the right side of the body) and the left carotid artery. Type C is the less common type of interrupted aortic arch. This type counts for approximately three percent of reported cases.

What Causes the Interrupted Aortic Arch?

Interrupted aortic arch (IAA) is a genetic disease. This indicates that this condition is passed down through ones family. Particularly, a section of a chromosome, for example, 22q11.2 deletion, causes 22q11.2 deletion syndrome (also known as DiGeorge syndrome), which affects the anatomy of the heart and its vessels.

IAA is an uncommon but potentially fatal illness that has to be treated immediately. When a baby is born with IAA, symptoms often appear immediately.

What Are the Symptoms of Interrupted Aortic Arch (IAA)?

The interrupted aortic arch does not present any signs or symptoms until the baby is born. When the ductus arteriosus begins to close, the symptoms begin to appear and may include:

• Abnormal rapid breathing.

• Feeding difficulties.

• Respiratory distress (fluid build-up in the air sac of the lungs).

• Cyanosis (bluish or grayish color of skin).

• Anuria (kidneys fail to produce urine).

• Difference in blood pressure between the right arm and lower extremities.

The condition can worsen and, ultimately, can lead to shock and death.

How Is the Interrupted Aortic Arch Diagnosed?

The diagnosis of the Interrupted Aortic Arch often begins with a thorough physical examination, including assessment of the infant's vital signs and observation of symptoms. Confirmatory tests may include:

• Arterial blood gas test.

• Chest radiograph.

• Electrocardiogram.

• Echocardiogram.

Other imaging modalities used for the diagnosis of this entity are:

• Cardiac angiography.

• Computed tomography angiography of the chest

• Magnetic resonance angiography.

What Is the Treatment of Interrupted Aortic Arch?

One of the initial treatments is an injection of prostaglandins. Prostaglandin is a medication that can be administered intravenously (IV). It continues to keep the ductus arteriosus open. This maintains blood circulation to the lower limbs until the aortic arch disruption is repaired surgically. The aim of the surgical treatment is to form unobstructed continuity with the ascending and descending aorta and to restore associated defects with the most typical atrial and/or ventricular septal defect. Either natural artery tissue, a homograph, or an autograph vascular patch is used in the process of restoration.

The main objectives of treatment are to stabilize and support the infant as long as surgery takes place. Treatment may include:

• Intratracheal intubation.

• Diuretic treatment can assist an infant in passing excess fluid.

• Administering inotropic drugs helps to improve the pumping action of the heart.

• Blood gasses (oxygen and carbon dioxide levels in the blood) and electrolytes (potassium and calcium levels in the blood) should be monitored and corrected.

• Nutritional support.

Management in Adults:

An interrupted aortic arch is an uncommon congenital defect. It has always been repaired surgically in childhood. Any adult patient with a history of interrupted aortic arch will need lifelong care from a doctor who specializes in congenital heart defects. Concerns may occur at the location of the original surgical repair. It may be linked to other defects in the heart that the individual was born with.

What Is the Outcome of an Interrupted Aortic Arch (IAA)?

Survival after full reconstruction of the aortic arch in the newborn period is 90 percent. Survival is not attainable without surgery.

What Is the Differential Diagnosis of Interrupted Aortic Arch (IAA)?

The differential diagnosis of Interrupted Aortic Arch (IAA) involves considering other congenital heart conditions and medical issues that may present with similar symptoms. It is crucial for healthcare professionals to distinguish IAA from other conditions to guide appropriate diagnostic and treatment strategies. Here are some conditions that may be part of the differential diagnosis for IAA:

• Atrial septal defect (ASD).

• Bicuspid aortic valve.

• Coarctation of the aorta.

• DiGeorge syndrome.

• Neonatal sepsis.

• Patent ductus arteriosis (PDA).

• Transportation of the great vessels.

• Truncus arteriosus.

• Velocardiofacial syndrome.

• Ventral septal defect.

Conclusion:

Interrupted aortic arch is a rare congenital heart anomaly that requires careful diagnosis and prompt intervention. While the condition poses significant challenges, advances in medical science and surgical techniques have greatly improved the outlook for affected individuals. Continued research and awareness are essential in further understanding and managing this complex cardiovascular anomaly. As medical knowledge and technology progress, the hope is that more effective and less invasive treatment options will become available, further enhancing the quality of life for those affected by Interrupted aortic arch.