Difference Between Ventricular Tachycardia and Ventricular Fibrillation

Ventricular tachycardia (Vtach) and ventricular fibrillation (Vfib) are both life-threatening cardiac arrhythmias that can occur in patients with underlying heart disease or structural abnormalities. While both conditions affect the ventricles of the heart and can result in sudden cardiac death, they differ in their underlying mechanisms, symptoms, and treatment approaches.

What is Ventricular Tachycardia?

Ventricular Tachycardia is a medical condition wherein the electrical impulses produced in the SA node are substituted by an ectopic pacemaker. This condition can also result due to intake of recreation medical drugs. The heart tissues will show contraction activity at regular time intervals but at a very escalated rate, mostly more than hundred beats/minute.

What is Ventricular Fibrillation?

Vfib is the most serious arrhythmia and is an uncontrolled, irregular heartbeat. Instead of one missed heart beat from the ventricles, individual experiences several impulses that start simultaneously from different places – all commanding the heart to beat. The heart beats are very fast, chaotic, irregular and sometimes reach three hundred beats/minute.

Ventricular Fibrillation is a condition where the electrical impulse conducting system functions in a haphazard manner. There is no coordination between the contraction activity, that triggers irregular rhythms in irregular time intervals. Here, rate and rhythm both get impacted unlike in tachycardia. Ventricular Fibrillation is a serious medical disease which if not treated immediately after it is diagnosed, leads to death.

Differences: Ventricular Tachycardia and Ventricular Fibrillation

One of the key differences between Vtach and Vfib is the underlying mechanism of each arrhythmia. While Vtach is caused by a single abnormal electrical circuit in the ventricles, Vfib is characterized by multiple and chaotic electrical circuits firing simultaneously. Another difference between the two is the severity of the condition. Vfib is considered more life- threatening than Vtach because it can lead to sudden cardiac arrest and death, while Vtach is generally less severe and can often be managed with medication or other interventions.

The treatment approaches for Vtach and Vfib also differ significantly. In patients with stable Vtach, medications such as beta-blockers, calcium channel blockers, or antiarrhythmic drugs may be used to slow the heart rate and prevent further episodes.

In some cases, an implantable cardioverter-defibrillator (ICD) may be recommended to monitor the heart's rhythm and deliver an electrical shock if a dangerous arrhythmia is detected. For patients with unstable Vtach or Vfib, immediate defibrillation is required to restore normal heart rhythm and prevent sudden cardiac death. Defibrillation involves the delivery of an electrical shock to the heart, either through external paddles or an implanted ICD.

The following table highlights the major differences between Ventricular Tachycardia and Ventricular Fibrillation −


Ventricular Tachycardia

Ventricular Fibrillation


Ventricular Tachycardia is a medical condition which is associated with the hearts irregular electrical impulses.

Such a condition arises mostly in people having valvular hear disease.

Ventricular fibrillation (VFib) is a medical condition in which the heart beats in an abnormal rhythm. The lower heart chambers show quivering activity and the heart is unable to pump any blood, leading to cardiac arrest.

Vfib is an emergency condition that is triggered by a heart attack.


The exact factor causing ventricular tachycardia is actually unknown. However, in most of the cases, it is triggered by some other hear disorder.

Some medical conditions that trigger ventricular tachycardia include −

  • Cardiomyopathy – chronic disease of the heart muscle.

  • Congestive heart failure (when the heart is not able to pump properly to maintain blood flow to meet the body’s requirements).

  • Structural heart disorder (cardiac defects which are congenital in nature that results due to previous heart attack).

  • Ischemic heart condition (that results because of interrupted flow of blood to the heart).

Several categories of Vtach are genetic, which means the medical issue passes down from a parent toa kid. These are

  • Catecholaminergic polymorphic ventricular tachycardia

  • Arrhythmogenic right ventricular dysplasia

Certain causes of vfib include −

  • Heart failure

  • Coronary artery disorder (Shock)

  • Aortic dissection

  • Cardiomyopathies

  • Aortic stenosis

  • Myocarditis

  • Electrical shock (injury caused by electric current)

  • Sepsis (severe body infection)

  • Drowning

  • LQTS (ventricular myocardial repolarization).

  • Medical drugs that impact electric currents in the heart (such as Na or K channel blockers).

  • Brugada syndrome (ECG abnormality resulting in sudden death in patients with structurally normal hearts)

Risk factors

Any medical disorder that induces strain or any kind of pressure on the heart cells or damages heart linings can increase the risk of ventricular tachycardia.

Improved lifestyle patterns or medical treatment can alleviate the risks associated with the below mentioned factors −

  • Heart disorders (for example, previous heart attack, inflammatory disorders of heart or some birth defects in heart and hypertrophic cardiomyopathy (a condition wherein a portion of the heart becomes quite thick without any obvious cause)

  • Intake of recreational drugs (psychoactive drugs consumed to induce a modified consciousness for pleasure)

  • Extreme electrolyte deformities

  • Side effects of certain medical drugs

  • A prior event of ventricular fibrillation

  • Already suffered heart attack

  • Malfunctioning of heart since birth (congenital heart disease)

  • Cardiomyopathy (disease of heart muscle)

  • Damage to heart cells because of electrocution

  • Intake of illegal drugs, like cocaine and methamphetamine

  • Notable electrolyte deformities, like with K or M


  • Vagal maneuvers

  • Cardioversion

  • Radio-frequency catheter ablation

  • Anti-arrhythmic drugs

  • Antiarrhythmic agent

  • Beta blocker

  • Blood pressure support


In summary, ventricular tachycardia (Vtach) and ventricular fibrillation (Vfib) are both serious cardiac arrhythmias that can lead to sudden cardiac death if left untreated. Vtach is a fast heart rhythm originating from the ventricles, while Vfib is a chaotic and irregular heart rhythm.

While both conditions affect the ventricles of the heart and can have similar symptoms, they differ in their underlying mechanisms, severity, and treatment approaches. Prompt recognition and management of these arrhythmias are critical for preventing sudden cardiac death and improving patient outcomes.

Updated on: 12-May-2023


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