From the Guidelines
Superior Vena Cava (SVC) syndrome is characterized by symptoms such as neck swelling, swelling of one or both arms, and swelling of the face and eyelids, as well as dyspnea, headache from cerebral venous hypertension, hoarseness of the voice, and cyanosis, which are a result of obstruction of the SVC by a mass in the right lung, lymph nodes, mediastinal structures, or thrombosis within the SVC 1.
Symptoms of SVC Syndrome
The symptoms of SVC syndrome can be divided into several categories, including:
- Facial and neck symptoms: facial swelling, especially around the eyes, neck swelling, and distended neck and chest veins
- Respiratory symptoms: shortness of breath, particularly when lying down, and cough
- Neurological symptoms: headaches that worsen when bending forward or lying down, dizziness, visual changes, and in severe cases, altered mental status
- Other symptoms: hoarseness, difficulty swallowing, and cyanosis These symptoms occur because the SVC is responsible for returning blood from the head, neck, upper chest, and arms to the heart, and when blocked, blood backs up in these areas, causing the characteristic swelling and congestion 1.
Causes of SVC Syndrome
The most common causes of SVC syndrome are malignancies, particularly lung cancer and lymphoma, that compress or invade the SVC, though blood clots, infections, and other conditions can also cause it 1.
Importance of Prompt Medical Attention
Prompt medical attention is essential as SVC syndrome can become life-threatening if severe obstruction develops rapidly, and the severity of symptoms is important in determining the urgency of intervention 1.
From the Research
Symptoms of Superior Vena Cava (SVC) Syndrome
The symptoms of SVC syndrome can be diverse and are primarily caused by the obstruction of blood flow through the superior vena cava. These symptoms include:
- Swelling of the face and hands 2, 3, 4, 5
- Chest pain 2
- Respiratory symptoms such as dyspnea, stridor, cough, hoarseness, and dysphagia 2, 3
- Neurologic manifestations including headaches, confusion, or visual/auditory disturbances 2, 4, 5
- A feeling of fullness in the head, facial, neck, and upper extremity edema 3
- Shortness of breath 3, 4, 5
- Symptoms generally worsen in a supine position 2
Severity and Presentation
The syndrome can present clinically on a spectrum, ranging from asymptomatic to life-threatening emergency 3. The severity of symptoms can vary, and understanding the pathophysiology of SVC syndrome requires knowledge of the anatomy and how the SVC drains blood from the head and upper extremities 2.
Common Causes
The most common cause of SVC syndrome remains malignancies, accounting for up to 60% of the cases 2, with non-small cell lung cancer, small cell lung cancer, and lymphoma being the most commonly associated malignancies 3. However, there is an increasing trend of benign etiologies secondary to thrombosis due to central lines/pacemakers or mediastinal fibrosis 6.