Ventricular tachycardia

Definition

Ventricular tachycardia (VT) is a type of fast heart rhythm that originates from the ventricles, causing them to beat rapidly, usually at a rate of more than 100 beats per minute. This condition can lead to insufficient blood flow to the body and may progress to more severe arrhythmias, such as ventricular fibrillation. VT is critical in the interpretation of electrocardiograms (ECGs) because it significantly affects the heart's electrical activity and overall functionality.

5 Must Know Facts For Your Next Test

1. Ventricular tachycardia can be classified as either monomorphic, where the QRS complexes appear uniform, or polymorphic, where they vary in shape.
2. VT can occur in patients with underlying heart conditions such as coronary artery disease or cardiomyopathy, but it can also happen in healthy individuals under certain circumstances.
3. The duration of VT is crucial; sustained VT lasts longer than 30 seconds and requires immediate medical attention, while nonsustained VT lasts less than 30 seconds and may not be immediately life-threatening.
4. Treatment options for ventricular tachycardia include medications, cardioversion, and implantable cardioverter-defibrillators (ICDs) for recurrent cases.
5. ECGs showing VT typically exhibit wide QRS complexes and may have a characteristic 'tombstone' appearance, indicating an urgent need for evaluation.

Review Questions

• How does ventricular tachycardia affect cardiac output and what implications does this have for patient management?
  • Ventricular tachycardia significantly reduces cardiac output because the ventricles do not have enough time to fill with blood between contractions. This can lead to symptoms such as dizziness, shortness of breath, and even loss of consciousness. Effective management often requires immediate medical intervention to restore normal rhythm and improve blood flow, using treatments like antiarrhythmic drugs or electrical cardioversion.
• Discuss how ventricular tachycardia is diagnosed through an electrocardiogram and what specific ECG features are indicative of this condition.
  • Ventricular tachycardia is diagnosed through an electrocardiogram (ECG) by looking for specific features such as wide QRS complexes that are consistent and appear at a rapid rate (over 100 beats per minute). The ECG may show a regular rhythm and a 'tombstone' appearance in the complex morphology. Recognizing these characteristics is crucial for timely diagnosis and management of this potentially life-threatening arrhythmia.
• Evaluate the potential long-term consequences of untreated ventricular tachycardia on a patient's overall health and cardiac function.
  • Untreated ventricular tachycardia can lead to serious long-term consequences, including heart failure, syncope, and sudden cardiac arrest due to progression to more severe arrhythmias like ventricular fibrillation. Over time, persistent VT can weaken the heart muscle, leading to diminished cardiac function and increased risk of future cardiovascular events. It is vital for healthcare providers to monitor and manage patients with VT to prevent these severe outcomes.

Related terms

Arrhythmia: A condition where the heart beats with an irregular or abnormal rhythm, which can range from harmless to life-threatening.

Electrocardiogram (ECG):

A test that records the electrical activity of the heart over a period of time, helping to diagnose various cardiac conditions, including ventricular tachycardia.

Ventricular Fibrillation:

A severe form of arrhythmia where the ventricles quiver ineffectively instead of pumping blood, often leading to cardiac arrest.