Home > Heart Disease > Tachycardia Get the Flash Player to see this player. Rate: (Click the stars to rate) Published on Jul 20, 2008 by AArshad, Views: 5143 Tachycardia refers to a heart rate greater than 100. Tachyarrhythmias can come from the top chambers of the heart, called supraventricular tachycardia-SVT, and ventricular tachycardia-VT- from the bottom chamber. VT is usually a life threatening arrhythmia associated with heart attack, heart disease, and certain medications. Symptoms include chest pain, shortness of breath, lightheadedness, and syncope-passing out. Some people at risk for VT will need an ICD-defibrillator.