The American journal of cardiology
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Randomized Controlled Trial Clinical Trial
Metoprolol in acute myocardial infarction. Development of myocardial infarction. The MIAMI Trial Research Group.
The effect of metoprolol on the development of an acute myocardial infarction (AMI) during days 0 to 3 and on late first and recurrent infarctions during days 4 to 15 has been investigated. Signs on electrocardiogram (ECG) were well balanced between the treatment groups at entry; 70% of patients had signs of suspected AMI and 19% of patients had normal ECGs. The remaining patients had abnormal ECGs but actual infarction could not be localized. ⋯ No difference in the effect of metoprolol regarding localization of the early AMI was observed. Late first myocardial infarction development (days 4 to 15) was observed in 20 patients (0.7%) in each group. Recurrent myocardial infarction tended to develop more frequently during days 4 to 15 in the placebo group compared with the metoprolol group (3.9% vs 3.0%, p = 0.08).(ABSTRACT TRUNCATED AT 250 WORDS)
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Randomized Controlled Trial Clinical Trial
Metoprolol in acute myocardial infarction. Mortality. The MIAMI Trial Research Group.
After 15 days there were 142 deaths in the placebo group (4.9%) and 123 deaths in the metoprolol group (4.3%), a difference of 13% (p = 0.29). The 95% confidence limits for the relative effect of metoprolol ranged from an 8% excess (-8%) to a 33% reduction (+33%) in mortality. There was generally a lower mortality rate for metoprolol-treated patients in most subgroups and a consistent tendency for a more pronounced difference between the treatment groups in those subgroups with a placebo mortality rate higher than the average for all placebo patients. ⋯ Using a simple model, the placebo mortality was found to increase with increasing number of 8 risk predictors defined from prestudy experience, from 0% in patients with no risk predictors to 11.6% in patients with any 5 or more of these risk factors. Similarly, there was an increase in the difference between the treatment groups in favor of metoprolol with increasing number of placebo risk factors. Metoprolol had no apparent effect in a low-mortality risk group (less than or equal to 2 risk factors), but there was a difference in mortality of 29% in favor of metoprolol in a high-risk group (greater than or equal to 3 risk factors) comprising one-third of the trial population.(ABSTRACT TRUNCATED AT 250 WORDS)
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Randomized Controlled Trial Clinical Trial
Metoprolol in acute myocardial infarction. Other clinical findings and tolerability. The MIAMI Trial Research Group.
Fifteen minutes after injection there was a fall in mean heart rate (18%, p less than 0.001), systolic blood pressure (10%, p less than 0.001) and rate-pressure product (27%, p less than 0.0001) in the metoprolol group of patients in the MIAMI trial. Hypotension and bradycardia not necessarily associated with withdrawal of drug were more common in the metoprolol group (p less than 0.001). Atrioventricular block I was more common in the metoprolol group (p less than 0.03), whereas no such difference was observed for atrioventricular block II and III, asystole or pacemaker implantations. ⋯ The trial medication was withdrawn temporarily more often in the metoprolol than in the placebo group (p less than 0.001). However, permanent withdrawal of trial medication occurred with a similar frequency overall in both groups. More patients were withdrawn from the study because of cardiovascular reasons in the metoprolol group (9%) than in the placebo group (5%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
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Randomized Controlled Trial Clinical Trial
Metoprolol in acute myocardial infarction. Arrhythmias. The MIAMI Trial Research Group.
Forty-five patients in the placebo (1.5%) and 29 in the metoprolol (1%) groups, respectively, were receiving antiarrhythmic drugs on a long-term basis before entry into the trial. Before randomization, 2.2% (n = 64) of the placebo and 1.7% (n = 50) of the metoprolol patients developed ventricular fibrillation (VF) in the hospital. The corresponding figures for atrial fibrillation or flutter were 3% (n = 87) and 3.3% (n = 94). ⋯ Although antiarrhythmic drugs were intended to be given only for major ventricular tachyarrhythmias a large proportion of patients received such treatment. Significantly more patients were treated with antiarrhythmics in the placebo (21.5%) than in the metoprolol group (19.2%, p = 0.03) during the study period, but predominantly during the first 5 days. Atrial fibrillation or flutter and other supraventricular tachyarrhythmias were significantly less frequent in the metoprolol than in the placebo group, as was the use of cardiac glycosides.(ABSTRACT TRUNCATED AT 250 WORDS)
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparative efficacy and tolerance of esmolol to propranolol for control of supraventricular tachyarrhythmia.
This multicenter, double-blind, randomized, parallel study compared the effectiveness and tolerance of intravenous esmolol with intravenous propranolol in patients with supraventricular tachyarrhythmia (heart rate [HR] greater than 120 beats/min). Efficacy was evaluated in 53 patients receiving esmolol and in 57 patients receiving propranolol. Patients randomized to esmolol received infusions of various doses of esmolol ranging from 50 to 300 micrograms/kg/min (each dose infused for 5 minutes) over a 30-minute titration period with intermittent placebo boluses of propranolol. ⋯ After discontinuation of study drugs, a more rapid reversal of the reduction in HR was observed in esmolol patients compared with those patients receiving propranolol. Adverse reactions were seen in 29 (45%) patients on esmolol and 11 (18%) patients on propranolol. The principle adverse reaction was hypotension, which was predominantly asymptomatic and found in 23 patients receiving esmolol and 4 receiving propranolol.(ABSTRACT TRUNCATED AT 250 WORDS)