Ventricular Tachycardia (VT)
Overview
Plain-Language Overview
Ventricular Tachycardia (VT) is a type of fast heart rhythm that starts in the lower chambers of the heart called the ventricles. It affects the heart's electrical system, causing the heart to beat very quickly and inefficiently. This can reduce the heart's ability to pump blood properly, leading to symptoms like dizziness, chest pain, or even loss of consciousness. VT can be dangerous because it may progress to a more serious rhythm called ventricular fibrillation, which can cause sudden cardiac arrest. The condition often occurs in people with underlying heart disease or after a heart attack.
Clinical Definition
Ventricular Tachycardia (VT) is defined as a rapid heart rhythm originating from the ventricles, characterized by at least three consecutive ventricular beats at a rate exceeding 100 beats per minute. It results from abnormal electrical activity due to reentry circuits, enhanced automaticity, or triggered activity within the ventricular myocardium. The most common causes include ischemic heart disease, cardiomyopathies, and structural heart abnormalities. VT is clinically significant because it can cause hemodynamic instability, leading to symptoms such as syncope or sudden cardiac death. It is classified as monomorphic or polymorphic based on QRS morphology on electrocardiogram. Prompt recognition and management are critical to prevent progression to ventricular fibrillation.