Supraventricular tachycardia is a rapid rhythm of the heart that begins in the upper chambers. When patients experience change in the normal sequence of electrical impulses and an abnormal heart rhythm occurs, they are said to be having an arrhythmia. Symptoms include palpitations, lightheadedness, dizziness, loss of consciousness, chest pain, shortness of breath. Modified Valsalva Maneuver places patient in a semi-recumbent position and instructed to exhale forcefully (strain) into a manometer