Pathophysiologic and pharmacokinetic determinants of the antihypertensive response to propranolol

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/117090/1/cpt1977223299.pd

Effect of beta-blockade on low heart rate-related ischemia during mental stress

To explore the effect of beta-adrenergic blockade on low heart rate-related (mental stress) ischemia, 19 patients with coronary artery disease were randomized into a double-blind crossover trial of metoprolol, 100 mg twice daily, and underwent serial mental stress/bicycle exercise studies. Mental stress-induced wall motion abnormalities occurred at a lower heart rate than exercise-induced wall motion abnormalities during placebo administration (81 ± 16 vs. 123 ± 20 beats/min, p < 0.05). Metoprolol reduced the mean magnitude of exercise-induced wall motion abnormalities (2.8 ± 2.0 vs. 1.6 ± 2.4, p = 0.003); improvement was related to the magnitude of hemodynamic beta-blockade effect. Metoprolol did not significantly reduce the mean magnitude of mental stress-induced wall motion abnormalities (3.0 ± 2.2 vs. 2.6 ± 2.2), although individual responses predominantly either improved (50%) or worsened (29%).Unlike exercise, the magnitude of hemodynamic beta-blockade did not predict mental stress response and metoprolol did not block mental stress-induced blood pressure elevations. Patients with abolition of exercise-induced ischemia were more likely to have reduction of mental stress-induced ischemia. Patients whose ischemia worsened with metoprolol during mental stress had more easily inducible ischemia, as assessed by exercise-induced placebo wall motion abnormality, chest pain and prior myocardial infarction. Beta-blockade was associated with a lowering of ischemia-related hemodynamic thresholds compared with placebo.These results suggest that beta-blockade has a variable effect on low heart rate-related ischemia that may be due to a lack of effect on mental stress-induced blood pressure elevation in patients with easily induced ischemia or to effects on coronary vasomotor tone, or both

Mode-specific impact of relaxation training for hypertensive men with type a behavior pattern

Multimodal therapy calls for selection of interventions on the basis of the specific modes of functioning that they are expected to affect. Mode-specificity assumptions were tested in a study of progressive muscle relaxation (PMR) training for type A men with borderline hypertension. It was expected that PMR would be especially effective in reducing psychophysiological reactivity and not effective for hostile cognition or behavioral anger expression. Forty-three subjects were randomly assigned to a control group receiving medical information or to information + PMR. PMR subjects reduced blood pressure reactivity to an anger-instigating role-play more than did controls. Although trait questionnaire measures of hostility and outward anger expression showed no group differences, a think-aloud measure of hostility and an observational measure of anger expression favored PMR. Discussion focuses on alternative explanations for these results, including the possibility that measures failing to show treatment effects were those confounded with negative affectivity