Ventricular Tachycardia (VT) of the Heart

Introduction

Ventricular tachycardia (VT) is a serious heart rhythm disorder that originates in the ventricles (the lower chambers of the heart). It can cause life-threatening complications if untreated. Understanding its causes, symptoms, and treatment options is crucial for managing this condition effectively.

Causes of Ventricular Tachycardia

VT is often associated with structural heart disease or electrical abnormalities. Common causes include:

• Coronary Artery Disease (CAD) – Reduced blood supply to the heart muscle can lead to scarring, which can disrupt electrical conduction.
• Heart Failure – Weakening of the heart muscle increases the risk of electrical abnormalities.
• Cardiomyopathies – Conditions like dilated or hypertrophic cardiomyopathy can create a substrate for VT.
• Electrolyte Imbalances – Low potassium (hypokalemia) or magnesium (hypomagnesemia) can trigger arrhythmias.
• Congenital Conditions – Some inherited syndromes such as Long QT Syndrome, Brugada syndrome, or Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) can cause VT.
• Myocarditis – Inflammation of the heart muscle can lead to electrical disturbances.

Symptoms of VT

Symptoms depend on the duration, rate, and underlying heart health. Key symptoms include:

• Palpitations (fast, irregular heartbeat)
• Dizziness or fainting (syncope)
• Chest pain
• Shortness of breath
• Weakness or fatigue
• Sudden cardiac arrest in severe cases

Diagnosis

Diagnosing VT involves a combination of clinical history, physical examination, and tests such as:

• Electrocardiogram (ECG) – The primary tool to detect VT with characteristic broad QRS complexes (>120 ms).
• Holter Monitor – A 24-hour ECG recording to capture intermittent episodes of VT.
• Echocardiogram – Evaluates heart structure and function.
• Cardiac MRI – Helps identify structural abnormalities and fibrosis.
• Electrophysiology Study (EPS) – Assesses electrical pathways in the heart to locate arrhythmic sites.
• Blood Tests – Help identify electrolyte imbalances or underlying conditions.

Treatment Options

Treatment depends on the severity and underlying cause:

Acute Management (Emergency Treatment)

• Stable VT: Can be treated with antiarrhythmic medications like amiodarone or lidocaine.
• Unstable VT: Requires immediate electrical cardioversion.
• Pulseless VT: Calls for immediate defibrillation and CPR.

Long-Term Treatment and Prevention

• Medications: Beta-blockers and antiarrhythmic drugs (e.g., amiodarone, sotalol) can prevent recurrence.
• Implantable Cardioverter-Defibrillator (ICD): A small device implanted in the chest that delivers shocks to correct life-threatening arrhythmias.
• Catheter Ablation: A procedure to destroy abnormal heart tissue responsible for VT.
• Lifestyle Changes: Managing risk factors such as hypertension, heart disease, and electrolyte imbalances.

Prognosis

The prognosis of VT varies depending on its cause and how well it is managed. In patients with structural heart disease, VT can be life-threatening and requires close medical supervision. In cases of idiopathic VT (without structural abnormalities), prognosis is generally better.

Conclusion

VT is a potentially dangerous arrhythmia requiring prompt diagnosis and treatment. Early intervention improves survival and quality of life. Patients at high risk should be monitored closely, and treatment should be tailored to their underlying condition.

Source recommendations

1. American Heart Association (AHA) Ventricular Arrhythmias and Sudden Cardiac Death Guidelines

1. https://www.ahajournals.org/doi/10.1161/CIR.0000000000000549
2. https://pubmed.ncbi.nlm.nih.gov/29097320/
3. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001193
4. https://www.sciencedirect.com/science/article/pii/S2405500X22010945
5. https://professional.heart.org/en/science-news/2017-guideline-for-management-of-patients-with-ventricular-arrhythmias-and-the-prevention-of-scd

2. European Society of Cardiology (ESC) Guidelines for Ventricular Arrhythmias and Sudden Cardiac Death

1. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Ventricular-Arrhythmias-and-the-Prevention-of-Sudden-Cardiac-Death
2. https://academic.oup.com/eurheartj/article/43/40/3997/6675633
3. https://pubmed.ncbi.nlm.nih.gov/36017572/
4. https://academic.oup.com/eurheartj/article/36/41/2793/2293363
5. https://pubmed.ncbi.nlm.nih.gov/26320108/