Update: cardiac antiarrhythmic drugs.

The last ten years have been a period of extensive research and development of new agents for the treatment of cardiac rhythm abnormalities. Several new subclass Ic agents have been developed, and more recently the class III agents have become the focus of attention. These new agents are all remarkable for their potency and potential for producing side effects. While none of these agents offers the perfect cure for the treatment or prevention of cardiac arrhythmias, they all offer advantages and options that are valuable for clinical management of patients.