[Torsade de pointes. Apropos of 54 cases]

A retrospective study of 54 torsades de pointe cases in a cardiology department enabled us to specify the main characteristics of this serious arrythmia often observed in intensive care units: --the diagnostic criteria: more than the pattern of tachycardia attack, late ventricular premature beats and particularly QT prolongation are necessary for proper diagnosis. These two criteria allow us to differentiate between torsades de pointe and multiform ventricular tachycardia with similar morphology especially in acute myocardial ischaemia; --their clinical repercussion: the shortness of circulatory arrest related to the spontaneous end of the arrythmia explains that the torsades de pointe often result in short faintings. Nevertheless, they may degenerate into ventricular fibrillation (17 p. 100) which, in cases of recurrence, induced four deaths in this study; --there are many possible aetiologies often associated (30 p. 100) in the same patient. Their research must be exhaustive in each case. The chronic bradycardias especially the atrioventricular blocks of two or three degree whether continuous or not are often responsible (57 p. 100). Then, the metabolic disorders, essentially hypokalaemia and constant drug administration (antiarrythmic agents belonging to group I of Vaughan William's classification, some antianginal drugs, vasodilatator drugs) are often chief causative agents. Other aetiologies are rare. In 9 p. 100 of cases, no aetiological factor is found; --the best treatment is to suppress aetiological factors, to stop the administration of antiarrhythmic drugs; torsades de pointe must be controlled by increasing the heart rate; pace maker stimulation is the best way of making QT shorter and thus of synchronizing ventricular depolarization.