PVC and NSVT in pa- tients with cardiovascular disease are common and have been associated with adverse outcomes.S2.2.2-12,S2.2.2-13 In CAST (Cardiac Arrhythmia Suppression Trials), treat- ment of patients with post-myocardial infarction (MI) who took antiarrhythmic medications (eg, flecainide, encainide, moricizine) increased the risk of death de- spite suppression of VA.S2.2.2-14,S2.2.2-15 Treatment of PVCs with antiarrhythmic medications has not been shown to reduce mortality and, in the post-MI population, treatment with class I sodium channel blocking medi- cations (eg, quinidine, flecainide) increases the risk of Likewise, in patients with a reduced LVEF class I, sodium channel blocking medications and d-sotalol increase the risk of death.S2.2.2-16,S2.2.2-17 Beta blockers, nondihydropyridines calcium channel block- CLINICAL STATEMENTS AND GUIDELINES Table 5. Table of Definitions of Commonly Used Terms in this Document Term Definition or Description Cardiac arrhythmia of 3 consecutive complexes originating in the ventricles at a rate >100 bpm (cycle length: <600 ms). Types of VT: Sustained: VT >30 s or requiring termination due to hemodynamic compromise in <30 s. Nonsustained/unsustained: 3 beats, terminating spontaneously. Monomorphic: Stable single QRS morphology from beat to beat. Polymorphic: Changing or multiform QRS morphology from beat to beat. Bidirectional: VT with a beat-to-beat alternation in the QRS frontal plane axis, often seen in the setting of digitalis toxicity or catecholaminergic polymorphic VT Monomorphic VT Polymorphic VT Bidirectional VT Torsades de pointesS2.2.2-2 Torsades de pointes is polymorphic VT that occurs in the setting of a long QT interval and is characterized by a waxing and waning QRS amplitude. It often has a long-short initiating sequence with a long coupling interval to the first VT beat and may present with salvos of NSVT. 