[Electrophysiological study of pro-arrhythmogenic effects of erythromycin].
Three cases of torsades de pointe induced by erythromycin have recently been reported. After observing a new case, the authors tried to demonstrate the possible mechanism of the arrhythmogenic action of this molecule. Twenty-two patients undergoing electrophysiological studies in the catheter laboratory to determine the cause of syncope were given an intravenous injection of 10 mg/Kg of erythromycin lactobionate. The drug was injected in 1 minute (bolus) in 11 patients (Group A). The other 11 patients (Group B) received the drug by slow intravenous infusion (20 minutes). Electrophysiological parameters were measured before and after erythromycin. A significant prolongation of the atrial refractory periods (+39 ms), ventricular refractory periods (+20 ms), QT (+20 ms) and QTC intervals (+42 ms) was observed in Group A. These electrophysiological effects could explain an arrhythmogenic action similar to that of antiarrhythmic drugs in Group I of Vaughan-Williams' classification. The slow intravenous infusion of erythromycin in Group B considerably reduced these undesirable secondary effects. This difference was directly related to serum concentrations of the molecule.
Ponsonnaille
J
J
Service de cardiologie, CHRU Saint-Jacques, Clermont-Ferrand.
Citron
B
B
Richard
A
A
Trolese
J F
JF
Chaperon
A
A
Barret
B
B
Gras
H
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000139:chemically induced*; D004562:Electrocardiography; D004917:Erythromycin / Q000009:adverse effects* / Q000494:pharmacology; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D013610:Tachycardia / Q000139:chemically induced
D004917:Erythromycin
Etude électrophysiologique des effets pro-arythmogènes de l'érythromycine.