Comparison of bevantolol and atenolol in chronic stable angina.

A randomized, double-blind, parallel-group study design was used to compare the antianginal efficacy of bevantolol (200 to 400 mg) and atenolol (50 to 100 mg) each administrated once daily for 8 weeks in 39 patients with chronic stable angina. Assessments were made using 24-hour ambulatory monitoring and treadmill exercise testing performed 22 to 24 hours after the last dose of medication. Both groups were comparable at the end of the placebo phase. In the bevantolol group, exercise time increased from 7.9 +/- 0.7 minutes with placebo to 9.3 +/- 0.7 minutes with bevantolol (mean +/- standard error of the mean) (p less than 0.05). Time to 1 mm ST depression was unaltered. Rest and exercise heart rate decreased (p less than 0.0001 and less than 0.0005, respectively) as did exercise double product (p less than 0.0001). In the atenolol group exercise time increased from 7.1 +/- 0.7 minutes with placebo to 8.2 +/- 0.8 minutes with atenolol (p less than 0.02). Time to 1 mm ST depression increased (p less than 0.005) and rest and exercise heart rate and double product decreased (p less than 0.0001 and less than 0.05, respectively). When within-group differences between placebo and active drug were compared for bevantolol and atenolol, no significant differences were detected. Both drugs were well tolerated and reduced ambulatory heart rate throughout the 24 hours. This study confirms that both bevantolol and atenolol are effective antianginal agents. Bevantolol compares well with atenolol in the treatment of patients with chronic angina, and there was a similar response to exercise testing with the 2 drugs.

Comparison of nicardipine and verapamil in the management of chronic stable angina.

Twenty-two patients with stable angina were studied in a randomised double-blind, placebo-controlled crossover trial to compare the antianginal effects of nicardipine (30 mg) and verapamil (120 mg), each given three times a day. Efficacy was assessed using treadmill exercise testing and 24-hour ambulatory electrocardiographic monitoring performed after an initial 2-week placebo phase and at the end of each 4-week active treatment period. Exercise time (mean +/- standard error of mean) increased from 7.4 +/- 0.5 min on placebo to 8.4 +/- 0.7 min on nicardipine (P less than 0.05) and to 9.9 +/- 0.7 min on verapamil (P less than 0.001). Resting heart rate was decreased by verapamil (P less than 0.002) and increased by nicardipine (P less than 0.02). Exercise heart rate was increased on nicardipine (P less than 0.005) but heart rate gain was higher on verapamil (P less than 0.01). Blood pressure and peak ST segment depression were unaltered by either drug but the time to 1 mm ST segment depression increased on both drugs. Ambulatory heart rates were lower on verapamil than on nicardipine and patient subjective preference was in favour of verapamil. This study confirms that both nicardipine and verapamil improve exercise capacity, but verapamil produces a greater improvement in exercise tolerance and indices of myocardial ischaemia whilst nicardipine is associated with an increase in the number of episodes of ST segment depression on ambulatory monitoring.

Radionuclide left ventricular ejection fraction: a comparison of three methods.

Three commercially available computer programs (a semiautomatic method, a manual method, and a regional method) were used to calculate left ventricular ejection fraction from the equilibrium multiple gated radionuclide ventriculograms obtained from 24 normal male subjects and 20 men with heart failure. In the normal subjects the ejection fraction values calculated by each method were significantly different (mean SD) difference between semiautomatic and manual 3.3 (5.8); between semiautomatic and regional 12.0 (6.3); and between manual and regional 8.7 (6.9]. In the patients with heart failure the ejection fraction values calculated by the semiautomatic method differed significantly from those calculated by the manual and regional methods (mean (SD) difference between semiautomatic and manual 3.4 (4.7); between semiautomatic and regional 4.9 (4.9); and between manual and regional 1.5 (6.2]. The ejection fraction values obtained by the semiautomatic method were generally higher and more consistent than those derived from the manual and regional methods. An ejection fraction of greater than or equal to 50% with the semiautomatic method would be regarded as normal but if the same normal range was applied to the regional method nine (38%) of the 24 normal subjects would appear to have an abnormal left ventricular function. Clinicians should be aware that the method used to generate a time-activity curve is an important consideration in the calculation of ejection fraction. Each centre should establish its own range and reproducibility for the method it uses to measure ejection fraction. These values should not be assumed to apply to any other method.

McArdle's disease presenting with rhabdomyolysis.

A patient with McArdle's disease is described who presented with rhabdomyolysis following severe exertion. An episode of acute renal failure four years earlier was probably secondary to a combination of myoglobinuria and an intravenous contrast agent.