Arrhythmias and acute myocardial infarction.

The most common arrhythmias associated with inferior-wall and anterior-wall myocardial infarction are bradycardia and supraventricular and ventricular tachycardia. Optimal treatment approaches are based on the pathophysiology of the infarct and the presence of contributing medical factors (eg, congestive heart failure, metabolic disorders). Temporary or permanent pacemaker therapy is helpful in some patients. Sudden death due to arrhythmia after myocardial infarction may be predicted and avoided in certain situations.

Efficacy, safety, hemodynamic effects, and pharmacokinetics of high-dose moricizine during short- and long-term therapy.

Moricizine, 15 mg/kg, was given to 10 patients with frequent ventricular ectopic depolarizations, eight of whom had previously been treated unsuccessfully with antiarrhythmic drugs. A single-blind inpatient study was followed by therapy for up to 6 months. Two patients developed aggravation of arrhythmia during inpatient therapy. Of the eight patients who completed the inpatient study, seven achieved greater than or equal to 80% suppression of total ventricular ectopic depolarizations (P less than 0.001). During inpatient therapy the mean of the individual patients' suppression of total ventricular ectopic depolarizations was 87.9%, paired ventricular beats 99.3%, nonsustained ventricular tachycardia 99.6%, and premature atrial contractions 89.0%. Suppression was maintained during long-term therapy. The PR interval increased 27% (P less than 0.001), QRS interval increased 10% (P less than 0.0001), QTc increased 1% (P not significant), and JTc decreased 2% (P not significant). Heart rate, blood pressure, and left ventricular performance at rest and exercise were unchanged by moricizine. Moricizine half-life was 9.2 +/- 3.4 hours. Plasma levels of moricizine decreased after 10 days of therapy, suggesting induction of metabolic enzyme systems.