<prompt> Answer this question truthfullyWhat interventions are available for premature ventricular contractions?  <response>: <reason> Class I 1. CPR should be performed in patients in cardiac arrest according to published basic and advanced cardiovascular life support algorithms Level of Evidence: A. 2. In patients with hemodynamically unstable VA that persist or recur after a maximal energy shock, intravenous amiodarone should be administered to attempt to achieve a stable rhythm after further defibrillation Level of Evidence: A. 3. Patients presenting with VA with hemodynamic instability should undergo direct current cardioversion Level of Evidence: A. 4. In Patients with polymorphic VT or VF with ST-elevation MI, angiography with emergency revascularization is recommended Level of Evidence: B-NR. 5. Patients with a wide-QRS tachycardia should be presumed to have VT if the diagnosis is unclear Level of Evidence: C-EO.Class IIa 1. In patients with hemodynamically stable VT, administration of intravenous procainamide can be useful to attempt to terminate VT Level of Evidence: A. 2. In patients with a witnessed cardiac arrest due to VF or polymorphic VT that is unresponsive to CPR, defibrillation, and vasopressor therapy, intravenous lidocaine can be beneficial Level of Evidence: B-R. 3. In patients with polymorphic VT due to myocardial ischemia, intravenous beta blockers can be useful Level of Evidence: B-R. 4. In patients with a recent MI who have VT VF that repeatedly recurs despite direct current cardioversion and antiarrhythmic medications VT VF storm, an intravenous beta blocker can be useful Level of Evidence: B-NR. Class IIb 1. In patients in cardiac arrest, administration of epinephrine 1 mg every 3 to 5 minutes during CPR may be reasonable Level of Evidence: A. 2. In patients with hemodynamically stable VT, administration of intravenous amiodarone or sotalol may be considered to attempt to terminate VT Level of Evidence: B-R. Class III: No Benefit 1. In patients with cardiac arrest, administration of high- dose epinephrine 1 mg boluses compared with standard doses is not beneficial Level of Evidence: A. 2. In patients with refractory VF not related to torsades de pointes, administration of intravenous magnesium is not beneficial Level of Evidence: A. Class III: Harm 1. In patients with suspected AMI, prophylactic administration of lidocaine or high- dose amiodarone for the prevention of VT is potentially harmful Level of Evidence: B-R. 2. In patients with a wide QRS complex tachycardia of unknown origin, calcium channel blockers eg, verapamil and diltiazem are potentially harmful Level of Evidence: C-LD. 