This document discusses beta-blockers, which are recommended for treating hypertension, angina, and myocardial infarction. Beta-blockers reduce mortality when used acutely and long-term after myocardial infarction. They are as effective for older patients, reducing mortality by 40%. Common side effects include dizziness, fatigue, and hypotension. Beta-blockers work by blocking beta receptors and lowering the cardiac workload and renin release. They should be initiated within days of a myocardial infarction and continued for up to three years.

1. Beta-Blockers
Use of Beta Blockers Following
Myocardial Infarction
By
Joyce M Toland BSN RN
February 12, 2017

2. • Beta-blockers such as Metaprolol are an
important cardiovascular drug class.
• They are recommended as first-line treatment
of:
– Hypertension
– Angina
– Myocardial infarction (Shin & Johnson, 2007).
Beta-Blockers

3. • Beta-blockers reduce mortality during both
acute and long-term management of
myocardial infarction.
• B-Blocker therapy should be started within
days of MI and continued for up to three
years.
• Can reduce total mortality, nonfatal MI and
sudden death by approximately 20%-30%
(Howard & Ellerbeck, 2000).
Beta-Blockers

4. Beta-Blockers
• Evidence shows beta-blockers are just as
effective in the elderly.
• Can be a 40% reduction in mortality in older
patients.
• Beta-blockers can be safely used in the elderly
population if therapy initiated at a lower dose
then titrated slowly (Howard & Ellerbeck,
2000).

5. Beta-Blockers
• Pharmacodynamics:
– Blocks central and peripheral beta receptors
– Lowers the cardiac output (lowering work load of
heart)
– Lowers sympathetic outflow
– Lowers the renin release
– Lowers stimulation of Renin Angiotensin
Aldosterone System (Long, 2015).

6. Beta-Blockers
• Interactions:
• Any other beta-blockers
• Other antihypertensive medications such as
alpha-2 blockers and calcium channel
blockers.
• Anti-arrhythmic medications such as
amiodarone have beta-blocking properties
and would also require close monitoring.

7. Beta-Blockers
• Adverse reactions:
– Hypotension
– Bradycardia
– Dizziness
– Fatigue
– Patient may feel worse on initiation of treatment
and on any dose titrations (Long, 2015)

8. Beta-Blockers
• Side Effects of Metoprolol:
– Dizziness or lightheadedness
– Tiredness
– Depression
– Dry mouth
– Stomach pain
– Vomiting
– Gas or bloating (Long, 2015).

9. Beta-Blockers
• Pharmacokinetics for Metoprolol:
• Dose……………………………………50-100mg
• Bioavailability …………………….40-50%
• Affected by food…………………Reduces bioavailability
• Metabolism………………………..Hepatic CYP2D6
• Half-life………………………………3-7 hours
• Protein binding………………….12%
• Elimination………………………..Renal
• Cardio selective………………....Yes
• (Long, 2015).

10. Beta-Blockers
• Drug Binding Issues:
– Beta-blockers bind to beta-adrenoceptors,
blocking the binding of norepinephrine.
– Beta-blockers block epinephrine to these
receptors.
– Inhibits normal sympathetic effects that act
through these receptors (“Wikipedia,” 2017).

11. Beta-Blockers
• Improving Communication:
– Educate providers on appropriate dosage.
– Keep same amount when changing from
immediate release to extended release (i.e.
Metoprolol tartrate 25mg 1 po bid =Metoprolol
50mg daily.)
– Oral to IV ratio = 2.5:1 ( i.e. 5mg IV = Metoprolol
tartrate 12.5mg)

12. Beta-Blockers
• Practice Setting:
– Used for acute Myocardial Infarction
– Not for first line use in hypertension
– Use with caution for Severe Peripheral vascular
disease, CHF Diabetes and Depression
Contraindicated:
Sinus Bradycardia
COPD
Heart Block
First and second degree block (Long, 2015)

13. Beta-Blockers
• References:
• Discovery and development of beta blockers . (2017). In Discovery and
development of beta blockers. Retrieved from
http://en.wikipedia.org/widi/Discovery_and_development_of_beta-
blockers
• Howard, P. A., & Ellerbeck, E. F. (2000, October 15, 2000). Optimizing beta-
blocker use after myocardial infarction. American Family Physician, 62(8),
1853-1860. Retrieved from
http://www.aafp.org/afp/2000/1015/p1853.html
• Klabunde, R. E. (2016). Beta-adrenoceptor antagonists (beta-blockers).
Cardiovascular Pharmacology Concepts, 1-9. Retrieved from
http://www.cvpharmacology.com/cardioinhibitory/beta-blockers
• Long, E. (2015). Hypertension [PowerPoint slides]. Retrieved from
http://www.blackboard.com
• Shin, J., & Johnson, J. A. (2007, June 27). Pharmacogenetics of B-blockers.
Pharmacotherapy, (6), 874-887. http://dx.doi.org/10.1592/phco.27.6.874