Are thrombolytics, beta blockers risky?

Look at these treatments for the elderly

Effective treatments for myocardial infarction (MI) are underutilized in the elderly, including aspirin, beta blockers, and thrombolytics, argues Stephen Meldon, MD, an attending physician in the ED at MetroHealth Medical Center in Cleveland.

The elderly actually have the greatest benefit in terms of thrombolytics reducing mortality, says Meldon.

"There is an 18% relative reduction in mortality. However, thrombolytics are given to less than half of elderly patients, often because of risk of stroke," he notes.1

Risk of stroke does increase three times with administration of thrombolytics, from .6% to 2%, Meldon notes. "If you have the ability to do catheterization and angioplasty, that’s what I would do for an elderly patient with an acute MI. But if you don’t have that opportunity, you should strongly consider thrombolytics," he advises. "Tell patients there is a very small risk of stroke; however, there is a big decrease in mortality, so the benefits outweigh the risks in eligible patients."2

Studies have shown an increased risk of cerebral hemorrhage in elderly patients receiving thrombolytic therapy, so screen for the following contraindications: major surgery or trauma within 10 days; history of central nervous system hemorrhage, tumor, aneurysm or arteriovenous malformation; hemorrhagic stroke within six months; spinal or intracranial surgery within three months; coma; bleeding diathesis (thrombocytopenia, hemophilia, platelet dysfunction); for streptokinase, prior administration within one year; prolonged cardiopulmonary resuscitation (>10 minutes); gastrointestinal or internal bleeding within three months; severe uncontrolled hypertension (>200/110). Pregnancy is also a contraindication.

Less than half of eligible patients receive beta blockers, which are very effective in reducing mortality of myocardial infarctions, Meldon reports. "There are a few strong contraindications, such as heart block and hypotension. But just because the patient is old, that doesn’t mean they shouldn’t get beta blockers," he says.

With beta blockers, there is a concern about exacerbating problems. "With beta blockers, you have a 23% reduction in mortality. These are really effective drugs, but there is a concern about side effects," Meldon notes.

Beta blockers can be given in titrated doses. "You can start with 5 mg IV metoprolol and go slow in increments to 15 mg, and see what the patient’s response is," Meldon recommends. Contraindications for beta blockers include a high degree of heart block, hypotension, and acute congestive heart failure, he says.

References

1. Krumholz HM, Murillo JE, Chen J, et al. Thrombolytic therapy for eligible elderly patients with acute myocardial infarction. JAMA 1997; 227:1,683-1,688.

2. Paul SD, O’Gara PT, Mahjoub ZA, et al. Geriatric patients with acute myocardial infarction: Cardiac risk factor profiles, presentation, thrombolysis, coronary interventions, and prognosis. Am Heart J 1996; 131:710-715.