Haemodynamic effects of class I antiarrhythmic agents.

In order to choose the most appropriate antiarrhythmic agent, the basic haemodynamic characteristics of class I antiarrhythmic agents must be known. Class Ia agents, quinidine and procainamide, have minor haemodynamic effects, while disopyramide causes serious left ventricular depression. Class Ib drugs are exceptionally well tolerated, and class Ic agents have the potential for adverse haemodynamic effects in patients with left ventricular dysfunction. In this article, haemodynamic effects of class I antiarrhythmic agents are described, with particular emphasis on their clinical implications.