Myocardial infarction beta-blockers

There is strong evidence that beta-blockers can reduce mortality by up to 23% post myocardial infarction. Beta-blockers should be used to reduce the risk of further cardiovascular disease events irrespective of whether the blood pressure is raised or not. There is no evidence that any beta-blocker is more effective than another in secondary prevention, hence a beta-blocker which is well tolerated and that can be taken once or twice daily should be used. Atenolol, bisoprolol or metoprolol are suitable agents. These agents are not specifically licensed post myocardial infarction but all are licensed for angina and the doses for this indication should be used i.e. 

Beta blockers Angina, hypertension, arrhythmias, and myocardial infarction... 

Beta-blockers can no longer be considered as first line monotherapy for uncomplicated hypertension in older patients since some studies suggest they are less effective than diuretics and no better than placebo in reducing cardiovascular outcomes. Their use in elderly with hypertension probably should be confined to those with other indications such as angina, following myocardial infarction or with heart failure. 

Krumholz HM, Radford MJ, Wang Y, Chen J, Heiat A, Marciniak TA. National use and effectiveness of beta-blockers for the treatment of elderly patients after acute myocardial infarction National Cooperative Cardiovascular Project. JAMA 1998 280(7) 623-9. 

Mangoni AA, Jackson SH. The implications of a growing evidence base for drug use in elderly patients. Part 3. Beta-adrenoceptor blockers in heart failure and throm-bolytics in acute myocardial infarction. Br J Chn Pharmacol 2006 61(5) 513-20. 

Bnnch TJ, Mnhlestein JB, Bair TL, Renlnnd DG, Lappe DL, Jensen KR et al. Effect of beta-blocker therapy on mortality rates and future myocardial infarction rates in patients with coronary artery disease but no history of myocardial infarction or congestive heart failure. Am J Cardiol 2005 95(7) 827-31. 

Miller CD, Roe MT, Mulgund J, Hoekstra JW, Santos R, Pollack CV et al. Impact of acute beta-blocker therapy for patients with non-ST-segment elevation myocardial infarction. Am J Med 2007 120(8) 685-92. 

In patients using orally administered beta-blockers, abrupt withdrawal may precipitate angina or lead to myocardial infarction or ventricular arrhythmias. 

Propranolol was the first blocker shown to be effective in hypertension and ischemic heart disease. Propranolol has now been largely replaced by cardioselective blockers such as metoprolol and atenolol. All B-adrenoceptor-blocking agents are useful for lowering blood pressure in mild to moderate hypertension. In severe hypertension, blockers are especially useful in preventing the reflex tachycardia that often results from treatment with direct vasodilators. Beta blockers have been shown to reduce mortality after a myocardial infarction and some also reduce mortality in patients with heart failure they are particularly advantageous for treating hypertension in patients with these conditions (see Chapter 13). 

Glucagon has also been used to stimulate insulin and C-peptide secretion, to see whether the islets still produce insulin, as a stimulatory test during pheochromocytoma, hyperinsulinism, and Zollinger-Ellison syndrome, or as an additive in upper gastrointestinal X-ray investigations (0.5-1 mg). It has been used in myocardial infarction, although its inotropic effects may present a risk. It has also been used to treat overdoses with beta-blockers (3) and calcium channel blockers (4), although its efficacy in such cases has only been demonstrated in animals (5) and to treat overdose with tricyclic antidepressants (6,7). 

People with diabetes have a much worse outcome after acute myocardial infarction, with a mortality rate at least twice that in non-diabetics. However, tight control of blood glucose, with immediate intensive insulin treatment during the peri-infarct period followed by intensive subcutaneous insulin treatment, was associated with a 30% reduction in mortality at 1 year, as reported in the DIGAMI study. In addition, the use of beta-blockers in this group of patients had an independent secondary preventive effect (198). The use of beta-blockers in diabetics with ischemic heart disease should be encouraged (199). 

Beta (/3)-blockers (e.g., propranolol, atenolol, oxyprenolol, pindolol) are used for treating hypertension, cardiac arrhythmias, angina pectoris, and myocardial infarction. These drugs have proven important in the management of alcohol withdrawal and hypothyroidism.56 -blockers also are used as prophylactics in... 

Page 95, figure 10.12 Redrawn after American Journal of Cardiology 87 823-826 (2001), Gottlieb S.S. et al. Comparative effects of three beta blockers (atenolol, metopro-lol, and propranolol) on survival after acute myocardial infarction. Reproduced with permission from Excerpta Medina Inc. 

---