Romano-Ward syndrome

Romano-Ward syndrome is a genetic disorder that affects the heart's electrical system, leading to abnormalities in the heart rhythm (arrhythmias). It is the most common form of inherited long QT syndrome, characterized by a prolongation of the QT interval on an electrocardiogram (ECG). This prolongation can lead to episodes of torsades de pointes, a specific type of ventricular tachycardia, which can result in fainting (syncope), seizures, or sudden death. Romano-Ward syndrome is inherited in an autosomal dominant pattern, meaning a single copy of the altered gene in each cell is sufficient to cause the disorder.

Causes and Genetics

Romano-Ward syndrome is caused by mutations in several genes, including KCNQ1, KCNH2, SCN5A, KCNE1, and KCNE2. These genes encode proteins that are essential components of ion channels, specifically potassium and sodium channels, which play critical roles in the cardiac action potential. The mutations lead to dysfunction of these ion channels, resulting in prolonged repolarization of the heart and an increased risk of arrhythmias.

Symptoms

The primary symptom of Romano-Ward syndrome is a prolonged QT interval, which can lead to potentially life-threatening arrhythmias. Individuals with this syndrome may experience episodes of syncope, particularly during exercise or emotional stress. In some cases, the arrhythmias can lead to sudden cardiac death. However, many individuals with Romano-Ward syndrome may remain asymptomatic throughout their lives.

Diagnosis

Diagnosis of Romano-Ward syndrome is primarily based on the clinical history, family history, and the presence of a prolonged QT interval on an ECG. Genetic testing can confirm the diagnosis by identifying mutations in the genes associated with the syndrome. It is important to differentiate Romano-Ward syndrome from other conditions that can cause prolonged QT intervals, including acquired long QT syndrome, which can be caused by certain medications or electrolyte imbalances.

Treatment

Treatment of Romano-Ward syndrome focuses on preventing arrhythmias and includes lifestyle modifications, medications, and in some cases, surgical interventions. Beta-blockers are the mainstay of treatment, as they have been shown to reduce the risk of arrhythmias in individuals with long QT syndrome. In patients who are at high risk for sudden cardiac death, an implantable cardioverter-defibrillator (ICD) may be recommended. Avoidance of medications that can prolong the QT interval and correction of electrolyte imbalances are also important aspects of management.

Prognosis

With appropriate management, individuals with Romano-Ward syndrome can lead normal lives. However, they are at an increased risk for life-threatening arrhythmias and sudden cardiac death. Regular follow-up with a cardiologist experienced in managing inherited arrhythmia syndromes is essential for ongoing assessment and management.