Electrophysiological study of intravenous pinaverium bromide in cardiology.

Pinaverium bromide is a musculotropic spasmolytic agent which acts by inhibiting transmembrane calcium movements, an effect similar to that of verapamil. Because of this, an investigation was carried out to see if it had any electrophysiological effects in patients with various cardiac disorders. In an open study, 10 patients received 2 mg pinaverium bromide intravenously. In a double-blind study, 10 patients received 4 mg pinaverium bromide intravenously and 10 patients placebo. Patients included those with either normal or pathological basal conduction, such as bundle-branch block and 1st degree atrioventricular block. Measurements were made of electrophysiological parameters before and 10 minutes after injection. The results showed that neither of the two doses of pinaverium bromide had any effect on atrial excitability, sino-atrial conduction, node and trunk atrioventricular conduction or on intraventricular conduction. No significant difference was seen in comparison with placebo. Pinaverium bromide had no anti-arrhythmic properties in these studies. Local, cardiac and general clinical tolerability was good in all patients.

[Early interruption of antiarrhythmia treatment in the acute phase of infarction complicated by ventricular arrhythmia]. / Interruption précoce du traitement antiarythmique à la phase aiguë des infarctus compliqués de troubles du rythme ventriculaire.

18 patients with myocardial infarction complicated by severe ventricular arrhythmias (polymorphic VEBs or bigeminy = 5; VT = 11; VF = 2) were treated with antiarrhythmics which were stopped after 24 hours (intravenous infusion of mexiletine 0.5 mg/kg/hr after a loading dose). This treatment resulted in one failure (recurrent VF) and 17 successes, after increasing the dose in 3 cases of VT. After stopping treatment, 72% of patients had no further arrhythmia. 5 cases had recurrent VT within 72 hours, which was controlled by oral mexiletine in 4 cases. The ejection fraction was significantly decreased in the group with recurrent VT. Plasma assays were of little help. Stopping the antiarrhythmic treatment after 24 hours does not therefore present any particular risks and can be proposed even in cases with severe arrhythmias.