VENTRICULAR TACHYCARDIA

Imagine your heart as a pump with four chambers. The lower chambers are called ventricles. VT is a type of irregular heartbeat where the ventricles beat unusually fast. This disrupts normal heart rhythm and blood flow. Ventricular tachycardia, often abbreviated as VT or V-tach, is a type of irregular heart rhythm known as arrhythmia. Unlike the usual heartbeat, which pumps blood at a steady pace, VT causes an abnormally rapid heartbeat originating from the lower chambers of the heart, called ventricles.

Normal heart rate:

A healthy heart beats around 60 to 100 times per minute.
Electrical signals control this rhythm, starting in the upper chambers (atria) and moving to the ventricles to pump blood.

What happens in Ventricular tachycardia?

Abnormal electrical signals take over in the ventricles, causing them to beat very fast (120 to 170 beats per minute or more).
The atria don’t have enough time to fill with blood and send it to the ventricles, reducing blood flow throughout the body.

Types of Ventricular tachycardia

Ventricular tachycardia (VT) manifests in various forms, each with distinct characteristics and implications:

Monomorphic Ventricular Tachycardia: In this type, the heart rhythm appears consistent from beat to beat when examined through an electrocardiogram (ECG). The term “monomorphic” denotes that each heartbeat wave looks similar on the monitoring equipment. Roughly 70% of VT cases fall into this category.
Polymorphic Ventricular Tachycardia: This is a particularly perilous form of arrhythmia. In polymorphic VT, the heart’s electrical activity becomes erratic and disorganized (“poly,” meaning multiple), posing a significant risk. Treatment may vary depending on the specific subtype of polymorphic VT.
Nonsustained Ventricular Tachycardia: This refers to VT episodes lasting less than 30 seconds. These brief episodes may come and go, presenting challenges in diagnosis during medical evaluations.
Sustained Ventricular Tachycardia: When VT persists for 30 seconds or longer or causes complications such as a sudden drop in blood pressure, it is classified as sustained VT. Prompt treatment is necessary in such cases.
Pulseless Ventricular Tachycardia: This form indicates that the ventricles beat so rapidly that they fail to fill adequately with blood, resulting in the absence of a detectable pulse. Pulselessness can occur irrespective of whether the VT is monomorphic or polymorphic.

Symptoms of Ventricular tachycardia

You might not experience any symptoms, especially with brief episodes.

Symptoms of ventricular tachycardia can vary but may include:

Lightheadedness or dizziness
Chest pain
Palpitations (heart pounding or fluttering)
Shortness of breath
Anxiety
Fainting
Neck tightness
Chest tightness or squeezing sensation
Fatigue

VT can lead to a sudden drop in blood pressure, depriving tissues and organs of oxygen, potentially resulting in sudden cardiac arrest, which can be fatal.

When to see a medical doctor

Prompt medical attention is warranted if you experience any of the following emergency signs or symptoms:

Chest pain
Difficulty breathing
Loss of consciousness
Prolonged or abnormal heartbeat exceeding 30 seconds
Absence of pulse

If you’ve encountered symptoms like lightheadedness, rapid heartbeats, or fainting, seeking medical advice promptly is advised.

Causes of Ventricular tachycardia

A glitch in the heart’s electrical system triggers the fast rhythm.
You’re more at risk if you’re older or have a family history of heart rhythm problems.
Other causes include:
- Prior heart attack
- Heart failure
- Weak heart muscle (cardiomyopathy)
- Heart scarring conditions (sarcoidosis)
- Circulatory problems from heart disease
- Electrolyte imbalances, particularly abnormal potassium and magnesium levels
- Myocarditis (inflammation of the heart muscle)
- Other underlying conditions such as sarcoidosis or acidosis
- Consumption of stimulants like cocaine or methamphetamine
- Excessive alcohol or caffeine intake
- Certain medications

When the underlying cause of VT cannot be identified, it is termed idiopathic ventricular tachycardia.

Diagnosing Ventricular tachycardia

Doctors review your medical history, symptoms, and perform tests like:
- Electrocardiogram (ECG) to record electrical activity
- Holter monitor (portable device worn for a day) to track heart activity over time
- Event monitor (worn for up to 30 days) to capture irregular heartbeats
- Imaging tests (X-ray, MRI, CT scan, echocardiogram) to examine your heart structure and function
- Blood tests to check for other health issues
- Implantable loop recorder
- Imaging tests (X-ray, MRI, CT, echocardiogram)
- Coronary angiogram
- Stress test
- Tilt table test
- Electrophysiological test
- Transesophageal echocardiography
- Blood tests

Treatment for VT

Treatment options for ventricular tachycardia (VT) vary depending on the severity of symptoms:

Cardioversion: This involves using an electric shock to restore the heart’s normal rhythm. It’s often employed as an emergency measure, especially if VT leads to fainting or low blood pressure.
Medications: Antiarrhythmic medications such as amiodarone, flecainide, lidocaine, propafenone, or sotalol may be prescribed to regulate heart rate. Beta-blockers, which block chemicals that accelerate heart rate, are also used, although they are less effective than cardioversion and may have side effects.
Cardiac Resynchronization Therapy (CRT): A small pacemaker implanted near the collarbone helps regulate electrical signals in the ventricles.
Implantable Cardioverter-Defibrillator (ICD): This device, placed under the skin near the collarbone, delivers a shock to reset the heartbeat if it becomes irregular. It’s particularly effective in preventing life-threatening complications like sudden cardiac death.
Cardiac Ablation: Also known as catheter or radiofrequency ablation, this procedure uses heat to destroy abnormal heart tissue causing VT, potentially curing the condition.
Maze Procedure: In this surgical intervention, small incisions are made in the upper part of the heart to create scar tissue, forming a maze that interrupts abnormal electrical signals.
Open-Heart Surgery: In certain cases where other treatments are ineffective or there are underlying heart problems, surgical intervention may be considered to eliminate or repair the cause of the rapid heartbeat.

It’s important to note that all medical procedures carry risks. Surgeries for VT, such as cardiac ablation, may lead to complications including heart and blood vessel damage, blood clots, increased bleeding, and infection.

Living with VT:

Additionally, lifestyle modifications and preventive measures can help manage VT:

Taking prescribed medication as directed by the doctor.
Considering an ICD if recommended by the medical team.
Collaborating with healthcare providers to establish a safe exercise regimen.
Monitoring symptoms and promptly reporting any changes to the doctor.
Receiving treatment for any concurrent health conditions.
Adopting a heart-healthy diet low in saturated fat, salt, and added sugar.
Avoiding smoking and excessive alcohol consumption.
Being cautious with stimulants like caffeine.
Implementing stress management techniques.
Prioritizing adequate sleep and maintaining a consistent sleep schedule.

Complications of VT:

Untreated VT can lead to serious problems like:
- Fainting
- Sudden cardiac arrest (fatal if not treated promptly)
- Heart failure

Preventing VT:

Preventing ventricular tachycardia involves focusing on heart-healthy habits, including a balanced diet, regular exercise, stress management, adequate sleep, and avoiding substances that may trigger irregular heart rhythms.
Always consult with healthcare professionals regarding the appropriate management and treatment plan tailored to individual needs and circumstances

Remember:

VT is a fast heartbeat originating in the lower heart chambers.
Early diagnosis and treatment are crucial to prevent complications.
Talk to your doctor if you have concerns about your heart health.