Direct antiarrhythmic therapy includes, either alone or in combination, Antiarrhythmic drugs Cardioversion-defibrillation Implantable cardioverter-defibrillators (ICDs) Pacemakers (and a special form of pacing, cardiac resynchronization therapy) Catheter ablation Surgery Patients with arrhythmias that have caused or are likely to cause symptoms of hemodynamic compromise may have to be restricted from driving until response to treatment has been assessed.