Ventricular Tachycardia: Causes, Symptoms, And Treatment

What Is Ventricular Tachycardia (VT)?

Ventricular Tachycardia (VT) is a serious cardiac arrhythmia characterised by a rapid heartbeat that starts from the ventricles — the lower chambers of the heart. Normally, electrical impulses begin in the sinoatrial (SA) node and travel in a coordinated manner. In VT, however, abnormal electrical signals arise in the ventricles, causing the heart to beat faster than 100 beats per minute — typically between 120 and 250 beats per minute.

This irregular rhythm disrupts the heart’s ability to pump blood efficiently to the body and brain. Short bursts of VT (known as nonsustained VT) may not cause noticeable symptoms, but prolonged episodes (sustained VT) can be life-threatening and may lead to sudden cardiac arrest or even death if untreated.

Ventricular tachycardia is more common in people with existing heart disease but can also occur in individuals with structurally normal hearts due to stress, electrolyte imbalances, medication effects, or inherited conditions.

Types of Ventricular Tachycardia

There are several types of ventricular tachycardia (VT), each differing in its electrical characteristics, duration, and potential severity. Understanding these variations helps doctors identify the root cause and tailor treatment effectively.

• Monomorphic VT: In this type, all heartbeats originate from the same abnormal site in the ventricles, creating identical waveforms on an ECG. It is most often seen in patients with structural heart disease, particularly those who have scar tissue from a previous heart attack, heart surgery, or cardiomyopathy. The regular rhythm pattern makes it easier to recognise, but it can still be dangerous if sustained.
• Polymorphic VT: This form occurs when abnormal electrical impulses arise from multiple areas in the ventricles, resulting in QRS complexes that vary in shape and size. According to the National Institutes of Health (NIH), polymorphic VT is commonly linked to acute myocardial ischaemia, severe electrolyte disturbances (especially low potassium or magnesium), or certain medication side effects. It can quickly progress to ventricular fibrillation, a life-threatening rhythm requiring immediate medical attention.
• Sustained VT: When ventricular tachycardia lasts longer than 30 seconds or requires medical intervention to terminate, it is classified as sustained VT. These episodes often cause significant symptoms such as dizziness, chest pain, or fainting because the rapid rhythm impairs the heart’s ability to pump blood effectively. Sustained VT is considered a cardiac emergency that may lead to sudden cardiac arrest if untreated.
• Nonsustained VT: Nonsustained episodes last less than 30 seconds and may not cause noticeable symptoms. However, their presence, especially in individuals with underlying heart disease, can be an early warning sign of electrical instability and an increased risk for more dangerous arrhythmias. They are often detected incidentally during Holter monitoring or other cardiac evaluations.
• Torsades de Pointes: A distinctive and potentially fatal subtype of polymorphic VT, Torsades de Pointes (French for “twisting of the points”) is characterised by a unique ECG pattern where the QRS complexes appear to spiral around the baseline. It is closely associated with a prolonged QT interval and is typically triggered by electrolyte imbalances, certain medications, or congenital long QT syndrome. Immediate treatment with magnesium and defibrillation is often necessary.

Causes & Risk Factors

The causes of ventricular tachycardia can vary widely depending on age, heart condition, and lifestyle. Some of the most common include:

• Coronary Artery Disease (CAD): Reduced blood supply to the heart muscles leads to scarring, a major trigger for abnormal electrical pathways.
• Previous Heart Attack: Scar tissue disrupts normal conduction and can generate erratic impulses.
• Cardiomyopathy: Both dilated and hypertrophic cardiomyopathies increase the heart’s electrical instability.
• Heart Failure: Damaged or weakened heart muscle predisposes individuals to arrhythmias.
• Electrolyte Imbalances: Low levels of potassium, calcium, or magnesium can trigger VT.
• Congenital or inherited heart conditions: Syndromes such as Brugada syndrome or long QT syndrome increase susceptibility.
• Medications: Certain antiarrhythmic or antidepressant drugs may prolong the QT interval, triggering VT.
• Substance Use: Cocaine, amphetamines, and excessive alcohol consumption can provoke arrhythmias.
• Genetic Factors: A family history of arrhythmias or sudden cardiac arrest is a known risk.

Symptoms of Ventricular Tachycardia

The ventricular tachycardia symptoms often depend on how fast the heart is beating, how long the episode lasts, and how much it disrupts blood flow. Common signs include:

• Heart palpitations: A fluttering or pounding feeling in the chest.
• Dizziness or lightheadedness: Caused by reduced oxygen supply to the brain.
• Shortness of breath: Due to impaired cardiac output.
• Chest pain or tightness: May resemble angina or a heart attack.
• Fainting (syncope): Occurs when the brain receives insufficient blood flow.
• Fatigue and weakness: Caused by reduced oxygen delivery to body tissues.
• Loss of consciousness or collapse: In severe cases, due to sudden cardiac arrest.

Complications of VT

If left untreated, ventricular tachycardia can cause several life-threatening complications. The most dangerous of these is ventricular fibrillation (VF), a chaotic rhythm where the heart quivers instead of pumping, leading to sudden cardiac death.

Repeated episodes of VT can also lead to heart failure, as the constant strain weakens the heart muscle. Additionally, reduced cardiac output may increase the risk of stroke or organ damage due to inadequate blood circulation. Thus, timely diagnosis and management are essential for survival and quality of life.

How VT Is Diagnosed

Diagnosing VT requires a comprehensive cardiac evaluation to pinpoint its cause and severity. Doctors follow a series of diagnostic steps:

1. Medical History & Physical Examination: Identifies symptoms, risk factors, and family history of arrhythmia or heart disease.
2. Electrocardiogram (ECG): The primary test to confirm VT, showing characteristic wide QRS complexes.
3. Holter Monitor or Event Recorder: Portable devices that continuously record heart rhythms over 24–48 hours or longer.
4. Echocardiogram (ECHO): Uses ultrasound to visualise the heart structure and detect any functional abnormalities.
5. Cardiac MRI or CT Scan: Helps identify scarring, inflammation, or congenital defects.
6. Electrophysiology Study (EPS): A specialised test where catheters are inserted into the heart to map electrical activity and locate arrhythmia sources.

Tests for Ventricular Tachycardia (VT)

A range of cardiac diagnostic tests can help confirm and monitor VT, including:

• ECG and Holter monitoring
• Cardiac enzyme tests and electrolyte panels
• Echocardiography
• Advanced cardiac imaging for structural assessment
• Cardiac Screen Profile, Cardiac Risk Profile, or Cardiac Channelopathy Gene Panel

These tests provide valuable insights into both the electrical activity and mechanical function of the heart.

Treatment Options

Treatment for Ventricular Tachycardia depends on its cause, duration, and whether it is sustained or nonsustained.

Medications:

• Antiarrhythmic drugs like amiodarone or sotalol stabilise the heart’s rhythm.
• Beta-blockers reduce heart rate and decrease stress on the heart muscle.
• Calcium channel blockers may be used for select cases of idiopathic VT.

Procedures and Devices:

• Catheter Ablation: A minimally invasive procedure that uses radiofrequency or cryoenergy to destroy small areas of cardiac tissue responsible for the arrhythmia.
• Implantable Cardioverter Defibrillator (ICD): A life-saving device implanted in the chest that automatically detects and corrects dangerous ventricular rhythms by delivering electrical shocks when needed.
• Pacemaker: Used in some cases to maintain a stable heartbeat.
• Surgery: Reserved for patients with structural heart problems or those not responding to other treatments.

Emergency Treatment for Ventricular Tachycardia

Sustained VT or cardiac arrest requires immediate emergency care:

1. Cardiopulmonary Resuscitation (CPR): Performed to maintain blood circulation until medical help arrives.
2. Defibrillation (Electric Shock): Delivered using a defibrillator or automated external defibrillator (AED) to restore normal rhythm.
3. Intravenous Medications: Drugs like lidocaine or amiodarone help suppress abnormal rhythms.
4. Intensive Monitoring: Continuous observation in a hospital setting ensures rapid stabilisation and prevents recurrence.

Long-Term Management

Long-term care focuses on preventing recurrence and improving quality of life:

• Regular cardiology follow-ups and ICD monitoring.
• Medication adherence to prevent arrhythmic episodes.
• Cardiac rehabilitation programmes for physical conditioning and stress reduction.
• Management of contributing conditions like high blood pressure or diabetes.
• Avoidance of stimulants and drugs that can trigger arrhythmias.

Lifestyle & Prevention Tips

While not all cases of VT can be prevented, several habits can reduce risk:

• Follow a heart-healthy diet: Include fruits, vegetables, and whole grains; limit sodium and trans fats.
• Stay physically active: Engage in moderate exercise approved by your doctor.
• Limit or avoid alcohol and caffeine: Both can raise heart rate and trigger arrhythmias.
• Quit smoking: Improves circulation, oxygen delivery, and overall cardiac function.
• Manage stress: Through yoga, meditation, or breathing exercises.
• Schedule regular checkups: Especially if you have a history of heart attack, hypertension, or cardiomyopathy.

When to Seek Immediate Medical Attention

If you experience persistent palpitations, chest pain, severe dizziness, fainting, or sudden shortness of breath, seek emergency medical attention immediately. These could be warning signs of sustained VT or sudden cardiac arrest. Early intervention can be the difference between a full recovery and a life-threatening emergency.

Conclusion

Ventricular Tachycardia (VT) is a serious but manageable heart rhythm disorder. Early diagnosis, timely treatment, and lifestyle changes can greatly improve outcomes and prevent complications like sudden cardiac arrest.

At Metropolis Healthcare, we help you stay proactive with 4000+ diagnostic tests, including specialised cardiac profiles, full-body health packages, and home sample collection across 10,000+ touchpoints. With quick turnaround and easy booking via our website, app, call, or WhatsApp, managing your heart health has never been simpler.

FAQs

What is ventricular tachycardia?

Ventricular Tachycardia is a fast, irregular heart rhythm originating from the ventricles. It disrupts normal blood flow and, in severe cases, can cause collapse or cardiac arrest.

Can Ventricular Tachycardia be life-threatening?

Yes. Sustained VT can degenerate into ventricular fibrillation, causing the heart to stop pumping effectively, leading to sudden cardiac death if not treated immediately.

How is Ventricular Tachycardia treated?

VT can be treated with antiarrhythmic and beta-blocker medications, catheter ablation for source elimination, an implantable Cardioverter Defibrillator (ICD) for rhythm correction, and emergency defibrillation for life-threatening episodes.

Can Ventricular Tachycardia be prevented?

While not always preventable, maintaining heart health through diet, exercise, avoiding stimulants, and regular screenings significantly lowers risk.

What are the warning signs of Ventricular Tachycardia?

The warning signs of a VT include rapid or pounding heartbeat, chest pain or tightness, dizziness or fainting, shortness of breath, or fatigue or weakness.

Is Ventricular Tachycardia curable?

In many cases, VT can be effectively managed or permanently corrected through catheter ablation or ICD therapy. Ongoing follow-ups ensure long-term stability and reduced recurrence.

References

• https://www.ncbi.nlm.nih.gov/books/NBK532954/
• https://www.mayoclinic.org/diseases-conditions/ventricular-tachycardia/symptoms-causes/syc-20355138
• https://my.clevelandclinic.org/health/diseases/17616-ventricular-tachycardia
• https://emedicine.medscape.com/article/159075-overview