Also known as:
Fast heart rhythms that begin in the lower chambers of the heart are called ventricular arrhythmias. They usually are fast and regular, such as ventricular tachycardia, or fast and irregular, such as ventricular fibrillation. These types of heart rhythms make it difficult for the heart to pump enough blood to the brain or the rest of the body and can be life-threatening. Ventricular arrhythmias may be caused by heart disease such as heart valve problems, impaired blood flow to the heart muscle (ischemia or a heart attack), a weakened heart muscle (cardiomyopathy) or heart failure.