prajmaline and Myocardial-Infarction

In 35 patients with acute myocardial infarction premature ventricular complexes were quantified from stored continuous electrocardiographic tape recordings using a semiautomated arrhythmia detection system. Seventeen patients, separated at random, received no antiarrhythmic drug and formed the control group. In nine patients prajmalium bitartrate was given orally at a dose of 60 mg. (20 mg. every 4 hours). Nine patients had permanent infusions of 2.1 mg./minute lidocaine (corresponding to a daily dose of 3 g.). In both treated groups premature ventricular complexes decreased significantly as compared to the spontaneous frequency in the control group. Six hours after the onset of therapy premature ventricular complexes were reduced to 37% of the initial value in the prajmalium bitartrate group and to 51% in the lidocaine group, whereas in the control group frequency increased (169%). The peak effect was reached after ten hours when premature ventricular complexes were reduced to 5% under prajmalium bitartrate and to 20% under lidocaine administration. Runs of premature ventricular complexes were nearly completely suppressed after administration of prajmalium bitartrate. Under lidocaine administration runs were moderately and not significantly reduced. Eight hours after the onset of therapy, runs were reduced to 8% of the initial value under prajmalium bitartrate and to only 79% under lidocaine. The effect of prajmalium bitartrate on runs of premature ventricular complexes was significantly more pronounced than the effect of lidocaine. The present study documents that orally administered prajmalium bitartrate is an alternative to intravenous administration of lidocaine in the treatment of ventricular arrhythmias after acute myocardial infarction.

Topics: Administration, Oral; Ajmaline; Anti-Arrhythmia Agents; Heart Ventricles; Humans; Injections, Intravenous; Lidocaine; Middle Aged; Myocardial Infarction; Prajmaline; Time Factors

Prajmalium bromide in combination with trimecaine was tested for effects on arrhythmias in the late period of canine experimental myocardial infarction. The combination given in subthreshold doses was found to restore sinus rhythm in 8 of 11 cases. It also decreased the maximum repolarization rate in rat papillary muscles to a greater extent than either drug given alone. The rate of spontaneous firing of Purkinje fibers from the ischemic zone was decreased by the combination of the drugs.

Topics: Animals; Arrhythmias, Cardiac; Dogs; Drug Therapy, Combination; Myocardial Infarction; Papillary Muscles; Prajmaline; Purkinje Fibers; Trimecaine

The effects of prajmalium bromide on normal and abnormal automaticity were studied in Purkinje fibers from dog hearts at late stages of experimental myocardial infarction. Prajmalium bromide (1.2 micromol/l) moderately reduced the frequency of normal and abnormal automaticity by 16 and 20% respectively. Prajmalium bromide induced early after-depolarizations, increased the frequency of spontaneous firing and decreased the maximum diastolic potential in the fibers that initially developed the automaticity of an intermediate type between normal and abnormal. It is suggested that antiarrhythmic effects of prajmalium bromide in the late stage of experimental myocardial infarction are not related to the influence of the drug on the abnormal automaticity in Purkinje fibers.

Topics: Action Potentials; Ajmaline; Animals; Culture Media; Diastole; Dogs; Dose-Response Relationship, Drug; Heart Conduction System; In Vitro Techniques; Myocardial Contraction; Myocardial Infarction; Prajmaline; Purkinje Fibers; Time Factors

Topics: Aged; Ajmaline; Cardiac Complexes, Premature; Humans; Jaundice; Male; Myocardial Infarction; Prajmaline

Topics: Aged; Ajmaline; Cardiac Complexes, Premature; Drug Evaluation; Female; Humans; Male; Middle Aged; Myocardial Infarction; Prajmaline

The present study was designed to assess the antiarrhythmic Prajmalium Bitartrate (PB) efficacy in the long term treatment of 22 patients with recent myocardial infarction and persistent, frequent, polimorphous, repetitive (two or more in a row) ventricular premature complexes (VPCs). VPCs were exposed by means of 24-hours ambulatory monitoring. The acute drug testing with a single dose of PB (30 mg) was followed by multiple maintenance therapy with a dose decreasing from 60 to 40 mg every day. Than, the long term antiarrhythmic action was evaluated by both monitoring and exercise stress testing (EST), symptom self-limited, in a 7 months and 28 days follow-up. A favorable therapeutic effect, with a reduction of VPCs frequency greater than 85% and the suppression of their greater Lown degrees, was obtained in 13 cases (59.2%) using PB alone and in 6 cases (27.2%) using PB associated with Amiodarone in 5 patients and with Metoprololo in one. No VPCs were present or they were less than 2 every 3 minutes during EST. Fourteen patients reported a recurrence of VPCs when the drug was stopped for 24-28 hours, after 3-5 months of the treatment. In 3 patients (13.6%) the PB was uneffective. In a case there was, during the acute drug testing, a paradox increasing of the arrhythmias, and in the other two an abnormal lengthening of QTc interval, while arrhythmia was unchanged. PB, alone or associated with other antiarrhythmic drugs, appears a well tolerated, handy and effective agent and it can be proposed as a drug of first choice for controlling VPCs.

Topics: Adult; Aged; Ajmaline; Ambulatory Care; Amiodarone; Arrhythmias, Cardiac; Drug Therapy, Combination; Electrocardiography; Female; Humans; Male; Metoprolol; Middle Aged; Monitoring, Physiologic; Myocardial Infarction; Prajmaline