The Sicilian gambit: an opening move that loses the game?

The Sicilian Gambit: an opening move that loses the game? The Sicilian Gambit is the title of a review article on antiarrhythmic drug therapy published simultaneously in the European Heart Journal and Circulation in 1991 1 ' 1. The rather peculiar name is a reference to the Queen's Gambit (an opening move in chess) and the fact that the article, considered by the authors as an 'opening move' in a new classification of antiarrhythmic drug therapy, was conceived at a meeting in Sicily. The authors of this article (Task Force of the Working Group on Arrhyth-mias of the European Society of Cardiology) have described themselves as 'a loosely organised group of basic and clinical investigators who met to discuss and pool their ideas about cardiac arrhythmias and their therapy and to share this information with the com-munity'. This would seem to be a well-intentioned and admirable aim. Why then should one distinguished investigator criticise the updated, expanded version of the Sicilian Gambit article and refer to it as 'an opening move which loses the game 121 '? At least part of the answer lies in the history of the classification of antiarrhythmic drug actions. The earliest antiarrhythmic drugs were discovered by chance and it was only some time later that the majority of these agents were found to reduce the fast inward sodium current into cardiac myocytes. The Vaughan Williams classification of antiarrhythmic drug action and its subsequent modifications' 3 " 51 were based on clinical observations, grouping together such agents according to their predominant electrophysiological effects. For instance, quinidine, disopyramide and procainamide were all found to prolong HV and QT intervals during sinus rhythm in addition to widening the QRS complex, actions that were designated as class la. In contrast, lignocaine, mexiletine and tocainide produced none of these effects (in fact shortening the QT interval) and this action was classed as lb. In addition some drugs, such as flecainide and encainide, produced QRS widening and HV lengthening with little effect on the QT interval, hence a further class termed lc. Other drugs were found to have anti-arrhythmic efficacy but did not have a prominent fast sodium current effect and the electrophysiological actions of these agents were classified as 2, 3, 4 and 5. For two decades clinical antiarrhythmic therapy was based on a combination of knowledge of the particular arrhythmia substrate in question, the Vaughan Williams classification and other …