Ventricular arrhythmias include ventricular fibrillation and ventricular tachycardia. Ventricular tachycardia and ventricular fibrillation can also be detected. These events have been associated with arrhythmias, palpitations, tachycardia and myocardial infarction. Verapamil is used for controlling ventricular rate in supraventricular tachycardia and migraine headache prevention. Congenital problems include long QT syndrome and catecholaminergic polymorphic ventricular tachycardia. Cardiovascular side effects may include orthostatic hypotension, sinus tachycardia, and QT-interval prolongation. The Valsalva maneuver may be used to arrest episodes of supraventricular tachycardia. Amiodarone can be used in individuals with hemodynamically stable ventricular tachycardia. It is sometimes known as paroxysmal atrial tachycardia (PAT). Also seen in catecholaminergic polymorphic ventricular tachycardia (CPVT). Individuals with hemodynamically "unstable" ventricular tachycardia "should not" initially receive amiodarone. It is a type of supraventricular tachycardia. Several types of supraventricular tachycardia are known to exist. Amiodarone may be used in the treatment of ventricular tachycardia in certain instances. Acute overdosage may be manifested by somnolence, tachycardia and hypertonicity.