The American journal of cardiology
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Randomized Controlled Trial Multicenter Study Comparative Study Clinical Trial
Esmolol versus verapamil in the acute treatment of atrial fibrillation or atrial flutter.
The effects of esmolol, an ultrashort-acting beta blocker, and verapamil were compared in controlling ventricular response in 45 patients with atrial fibrillation or atrial flutter, in a randomized, parallel, open-label study. Patients with either new onset (less than 48 hours, n = 31) or old onset (greater than 48 hours, n = 14) of atrial fibrillation or flutter with rapid ventricular rate were stratified to receive esmolol (n = 21) or verapamil (n = 24). Drug efficacy was measured by ventricular rate reduction and conversion to sinus rhythm. ⋯ Mild hypotension was observed in both treatment groups. Esmolol compares favorably with verapamil with respect to both efficacy and safety in acutely decreasing ventricular response during atrial fibrillation or flutter. Moreover, conversion to sinus rhythm is significantly more likely with esmolol.
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Randomized Controlled Trial Clinical Trial
Influence of long-term metoprolol treatment on early and late exercise test performance after acute myocardial infarction.
The effect of therapy on exercise performance during a 3-year follow-up after acute myocardial infarction (AMI) was evaluated in a double-blind randomized comparison between 154 patients given metoprolol (100 mg twice daily) and 147 patients given placebo. Exercise tests were performed 1.5, 6, 12, 24 and 36 months after AMI. Maximal accomplished workloads were similar in the 2 groups throughout follow-up. ⋯ Exercise-induced ventricular arrhythmias were significantly more common in the placebo group during the initial 6 months. Death, another AMI or both were significantly reduced by metoprolol treatment in patients with exercise-induced ST depression greater than or equal to 1 mm at the 6-week test. In a multiple logistic regression analysis maximal accomplished workload at 6 weeks (p less than 0.026), male sex (relative risk [rr] = 3.57, p = 0.016), previous AMI (rr = 3.07, p = 0.001), therapy with placebo (rr = 2.14, p = 0.007) and left ventricular failure (rr = 2.04, p = 0.023) were shown to carry independent prognostic information as well as exercise-induced ST-depression (greater than or equal to 1 mm) in placebo-treated patients (rr = 2.70, p = 0.01).
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of esmolol and nitroprusside for acute post-cardiac surgical hypertension.
Because acute systemic hypertension early after cardiac surgery has been linked to catecholamine elevation, an open-label, randomized, crossover study was performed to compare the efficacy of esmolol, a new ultra-short-acting intravenous beta-blocking agent, to nitroprusside, the standard therapy. Controlled drug infusions to maximal dosage (esmolol, 300 micrograms/kg/min, and nitroprusside, 10 micrograms/kg/min) were titrated to achieve at least a 15% reduction in systolic pressure. ⋯ Diastolic BP was reduced from 71 +/- 12 to 64 +/- 11 mm Hg with esmolol and from 71 +/- 12 to 52 +/- 13 mm Hg with nitroprusside infusion (both p less than 0.05). Esmolol infusion resulted in decreased heart rate, cardiac index and stroke volume index and increased right atrial pressure (all p less than 0.05), whereas nitroprusside infusion resulted in increased heart rate and cardiac index and decreased right atrial pressure, pulmonary arterial wedge pressure and systemic vascular resistance (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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Randomized Controlled Trial Clinical Trial
Metoprolol in acute myocardial infarction. Patients and methods. The MIAMI Trial Research Group.
The effects of early intervention with metoprolol in patients with suspected or definite acute myocardial infarction (AMI) have been assessed in a randomized, double-blind, placebo-controlled international study. Patients aged 75 years or younger were eligible for entry if they presented to a coronary care unit within 24 hours of the onset of symptoms of an AMI. Exclusion criteria included current treatment with a beta blocker or calcium-channel blocker, heart rate less than or equal to 65 beats/min, systolic blood pressure less than or equal to 105 mm Hg, contraindications and other administrative reasons. ⋯ The study period was 15 days in addition to the day of randomization. The patients' clinical history and status at entry were documented. The following outcome variables were recorded: mortality, development of AMI, serum enzyme activity, electrocardiographic signs of AMI, late or recurrent AMI, arrhythmias, treatment of chest pain, concomitant treatment, adverse events and details of treatment with trial medication.
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Randomized Controlled Trial Clinical Trial
Metoprolol in acute myocardial infarction. Enzymatic estimation of infarct size. The MIAMI Trial Research Group.
The maximum serum activity for aspartate aminotransferase (s-ASAT) during the first 3 days was recorded in 5,507 patients with suspected or definite acute myocardial infarction. The s-ASAT activity was corrected for the normal range from each center. ⋯ Univariate analyses indicated that the delay time between onset of symptoms and randomization and sympathetic activity at entry significantly influenced the effect of metoprolol. A similar decrease in serum enzyme activity after metoprolol treatment was observed independent of signs of infarct localization on the entry electrocardiogram.