Ventricular tachycardia

Ventricular tachycardia (V-tach or VT) is a type of regular, fast heart rate that arises from improper electrical activity in the ventricles of the heart. Although a few seconds may not result in problems, longer periods are dangerous. Short periods may occur without symptoms, or present with lightheadedness, palpitations, or chest pain. Ventricular tachycardia may result in ventricular fibrillation and turn into sudden death. It is found initially in about 7% of people in cardiac arrest. Ventricular tachycardia (V-tach or VT) is a type of regular, fast heart rate that arises from improper electrical activity in the ventricles of the heart. Although a few seconds may not result in problems, longer periods are dangerous. Short periods may occur without symptoms, or present with lightheadedness, palpitations, or chest pain. Ventricular tachycardia may result in ventricular fibrillation and turn into sudden death. It is found initially in about 7% of people in cardiac arrest. Ventricular tachycardia can occur due to coronary heart disease, aortic stenosis, cardiomyopathy, electrolyte problems, or a heart attack. Diagnosis is by an electrocardiogram (ECG) showing a rate of greater than 120 beats per minute and at least three wide QRS complexes in a row. It is classified as non-sustained versus sustained based on whether it lasts less than or more than 30 seconds. The term ventricular tachycardias refers to the group of irregular heartbeats that includes ventricular tachycardia, ventricular fibrillation, and torsades de pointes. In those who have a normal blood pressure and strong pulse, the antiarrhythmic medication procainamide may be used. Otherwise, immediate cardioversion is recommended. In those in cardiac arrest due to ventricular tachycardia, cardiopulmonary resuscitation (CPR) and defibrillation is recommended. Biphasic defibrillation may be better than monophasic. While waiting for a defibrillator, a precordial thump may be attempted in those on a heart monitor who are seen going into an unstable ventricular tachycardia. In those with cardiac arrest due to ventricular tachycardia, survival is about 45%. An implantable cardiac defibrillator or medications such as calcium channel blockers or amiodarone may be used to prevent recurrence. While a few seconds may not result in problems, longer periods are dangerous. Short periods may occur without symptoms or present with lightheadedness, palpitations, or chest pain. Ventricular tachycardia may result in cardiac arrest and turn into ventricular fibrillation. Ventricular tachycardia can occur due to coronary heart disease, aortic stenosis, cardiomyopathy, electrolyte problems (e.g., low blood levels of magnesium or potassium), inherited channelopathies (e.g., long-QT syndrome), catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular dysplasia, or a heart attack.