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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adrenergic beta-Antagonists, Adult, Aged, Angina Pectoris, Calcium Channel Blockers, Cross-Over Studies, Diltiazem, Electrocardiography, Exercise Test, Female, Humans, Male, Metoprolol, Middle Aged, Myocardial Ischemia, Random Allocation.
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Is silent ischemic interval on exercise test a predictor of response to drug therapy : a randomized crossover trial of metoprolol versus diltiazem in stable angina? Context: There is no method available to predict the relative antianginal efficacy of beta blockers and calcium-channel antagonists. The present study was undertaken to assess the role of silent ischemic interval (SII) on exercise treadmill test (ETT) as a predictor of response to therapy with metoprolol and diltiazem in patients with stable angina. Thirty-four patients with stable angina were divided into two groups depending upon the presence or absence of an SII gap of at least 1 min between onset of ST depression and appearance of angina on ETT. Metoprolol (50-100 mg twice daily) and diltiazem (60-120 mg three times daily) were randomly assigned for 6 weeks to patients in each group, and then patients were crossed over for further 6 weeks after a washout period of 2 weeks. Antianginal efficacy was assessed by clinical and exercise parameters. In patients with SII, the clinical responder rate was better with metoprolol than with diltiazem (90 vs. 60%, respectively), and on ETT, metoprolol produced significant improvement in the total exercise time (p< 0.01), time to 1 mm ST depression (p <0.01), time to angina (p <0.01), and a significant decrease in peak rate-pressure product (p<0.001), whereas diltiazem had no significant effect on exercise parameters. However, in patients without SII, metoprolol and diltiazem had a similar clinical responder rate (57%), and both produced a significant increase in total exercise time (p < 0.01), time to 1 mm ST depression (p < 0.01), and time to angina (p < 0.01). In addition, metoprolol had a significant effect on peak rate-pressure product (p < 0.001).
assistant
Silent ischemic interval on ETT can be a predictor of response to antianginal therapy in stable angina, as patients with SII respond better to metoprolol and those without SII respond equally to both metoprolol and diltiazem. Final Decision: yes