Symptoms Of Aberrant Right Subclavian Artery

Symptoms of Aberrant Right Subclavian Artery: A Comprehensive Guide

The aberrant right subclavian artery (ARSA), also known as the right subclavian artery arising from the descending aorta, is a relatively common congenital vascular anomaly. While often asymptomatic and discovered incidentally, ARSA can present with a range of symptoms, depending on its course and the presence of associated complications. Understanding these symptoms is crucial for timely diagnosis and appropriate management. This comprehensive guide will explore the various ways ARSA can manifest, helping healthcare professionals and patients alike recognize its potential clinical implications.

Understanding the Anatomy of an Aberrant Right Subclavian Artery

Before diving into the symptoms, it's essential to grasp the anatomical basis of ARSA. In a typical arrangement, the right subclavian artery originates from the brachiocephalic trunk, branching off the aortic arch. In ARSA, however, the right subclavian artery arises directly from the descending aorta, typically posterior to the esophagus and trachea. This aberrant origin can lead to a variety of clinical presentations. The artery's atypical course can compress surrounding structures, leading to the symptoms experienced by individuals with this anomaly.

The Significance of the Anomalous Course

The path the aberrant right subclavian artery takes is pivotal in determining the symptoms a patient will experience. The artery's passage behind the esophagus and trachea can lead to compression, resulting in vascular and/or neurologic symptoms. The severity of symptoms correlates strongly with the degree of compression and the individual's sensitivity to this compression.

Common Symptoms of Aberrant Right Subclavian Artery

The symptoms associated with ARSA are diverse and can range from subtle to life-threatening. The most frequently observed symptoms include:

1. Dysphagia Lusoria: Difficulty Swallowing

This is arguably the most characteristic symptom of ARSA. Dysphagia lusoria, literally meaning "swallowing difficulty caused by a deceitful artery," arises from the compression of the esophagus by the aberrant artery. This compression can cause a feeling of food getting stuck, especially solid foods. The sensation can vary in severity, from mild discomfort to significant difficulty swallowing, often resulting in choking episodes. The intensity of the dysphagia often correlates with the size of the artery and the degree of its posterior displacement.

2. Dyspnea: Shortness of Breath

In some cases, the ARSA can compress the trachea or left recurrent laryngeal nerve, leading to dyspnea or shortness of breath. This symptom is less common than dysphagia but can be a significant clinical concern. It's often associated with a feeling of tightness in the chest and can be exacerbated by physical activity or lying down. The severity of dyspnea can range from mild to severe, potentially impacting the patient's quality of life considerably.

3. Hoarseness and Vocal Cord Paralysis

Compression of the left recurrent laryngeal nerve, often occurring alongside tracheal compression, can result in hoarseness. This is due to the disruption of the nerve's function, which innervates the vocal cords. In severe cases, vocal cord paralysis may occur, leading to a significant impairment of speech. This complication warrants immediate medical attention.

4. Vascular Symptoms: Rarely Observed

While compression of surrounding structures is the more common cause of symptoms, in rare instances, ARSA can lead to vascular problems. These are typically related to stenosis or occlusion of the aberrant artery itself, resulting in reduced blood flow to the right arm. Symptoms may include intermittent claudication (pain in the arm during exertion), coldness in the right arm, and diminished pulses. However, these vascular symptoms are less frequently observed than the esophageal and tracheal compression-related symptoms.

5. Chest Pain: A Non-Specific Symptom

Chest pain can be a symptom associated with ARSA, but it's important to note that chest pain is a non-specific symptom with many possible causes. When associated with ARSA, the chest pain is usually related to the compression of adjacent structures and the resulting inflammation. Its character can be described as a dull ache or pressure, often localized to the retrosternal region (behind the breastbone).

Less Frequent, but Significant, Manifestations of ARSA

While dysphagia is the hallmark symptom of ARSA, certain less common presentations warrant attention:

• Subclavian steal syndrome: Although rare with ARSA, retrograde flow from the vertebral artery into the subclavian artery can occur, leading to subclavian steal syndrome. This is characterized by blood being diverted from the brain to the arm, potentially causing dizziness or neurological deficits.
• Aneurysm formation: The aberrant artery can be prone to aneurysm formation, though this remains a relatively infrequent complication. The rupture of an aneurysm could be life-threatening.
• Thoracic outlet syndrome: In some cases, the unusual course of the ARSA can exacerbate or contribute to thoracic outlet syndrome, which involves compression of nerves and blood vessels in the space between the clavicle and the first rib.

Diagnosis of Aberrant Right Subclavian Artery

Accurate diagnosis of ARSA is crucial for appropriate management. Several imaging techniques are used to confirm the diagnosis and assess the severity of compression:

• Chest X-ray: This initial imaging modality often reveals an abnormal aortic arch and may suggest the presence of ARSA.
• Computed Tomography (CT) Angiogram: Provides detailed images of the blood vessels, allowing for precise visualization of the aberrant artery and its relationship to surrounding structures.
• Magnetic Resonance Angiogram (MRA): An alternative non-invasive technique offering excellent visualization of the vascular anatomy.
• Barium swallow: This procedure helps to assess the degree of esophageal compression caused by the aberrant artery.

Treatment and Management of Aberrant Right Subclavian Artery

The management of ARSA depends largely on the presence and severity of symptoms. Many individuals with ARSA remain asymptomatic throughout their lives and require no intervention. However, symptomatic patients may require treatment.

• Surgical intervention: In cases with significant dysphagia, tracheal compression, or recurrent laryngeal nerve compression, surgical intervention may be necessary. The surgical approach typically involves the relocation or resection of the aberrant vessel. This is a complex procedure requiring specialized surgical expertise.
• Conservative management: For patients with mild symptoms, conservative management strategies may suffice. These can include dietary modifications to improve swallowing and medications to manage associated symptoms like dysphagia or heartburn.
• Regular monitoring: Asymptomatic individuals with ARSA may benefit from regular follow-up appointments to monitor for the development of any symptoms.

Conclusion: Living with an Aberrant Right Subclavian Artery

Aberrant right subclavian artery is a congenital vascular anomaly that can present with a spectrum of symptoms, ranging from mild swallowing difficulties to severe respiratory compromise. Early and accurate diagnosis is key to appropriate management. While surgical intervention may be necessary in symptomatic cases, many individuals with ARSA live symptom-free lives. Understanding the anatomical basis of ARSA, its potential clinical implications, and the diagnostic and management strategies is essential for healthcare professionals and patients alike to navigate this congenital vascular anomaly effectively. This knowledge empowers individuals to seek timely medical attention when necessary and to live full and productive lives, even in the presence of this anatomical variation.