Antianginal DrugsLilley Reading and Workbook – Chap 23
Supply and Demand: ◦ When the supply of oxygen and nutrients in the blood is
insufficient to meet the demands of the heart The heart requires a large supply of oxygen to
meet the demands placed on it Ischemia
◦ Poor blood supply to an organ - myocardium Ischemic heart disease
◦ Poor blood supply to the heart muscle◦ Atherosclerosis or Coronary artery disease
Myocardial infarction (MI)◦ Necrosis, or death, of cardiac tissue◦ Disabling or fatal
Chronic stable angina (also called classic or effort angina)
Unstable angina(also called preinfarction or crescendo angina)
Vasospastic angina(also called Prinzmetal’s or variant angina)
Increase blood flow to ischemic heart muscleand/or Decrease myocardial oxygen demand
Minimize the frequency of attacks and decrease the duration and intensity of angina pain
Improve the patient’s functional capacity with as few adverse effects as possible
Prevent or delay the worst possible outcome, MI
Nitrates/nitrites
(beta)-blockers
Calcium channel blockers
Available forms
Sublingual* Buccal* Chewable tablets Oral capsules/tablets Intravenous solutions Ointments* Transdermal patches* Translingual sprays* *Bypass the liver and the first-pass effect
Vasodilation due to relaxation of smooth muscles Potent dilating effect on coronary arteries Used for prevention and treatment of angina Vasodilation results in reduced myocardial
oxygen demand Nitrates cause dilation of both large and small
coronary vessels Nitrates alleviate coronary artery spasms
Result: oxygen to ischemic myocardial tissue
Rapid-acting forms◦ Used to treat acute anginal attacks◦ Sublingual tablets; intravenous infusion
Long-acting forms◦ Used to PREVENT anginal episodes
Nitroglycerin
Prototypical nitrate Large first-pass effect with oral forms Used for symptomatic treatment of ischemic
heart conditions (angina) IV form used for BP control in perioperative
hypertension, treatment of HF, ischemic pain, pulmonary edema associated with acute MI, and hypertensive emergencies
isosorbide dinitrate (Isordil, Sorbitrate, Dilatrate SR)
isosorbide mononitrate (Imdur, Monoket, ISMO)
Uses: Acute relief of angina Prophylaxis in situations that may provoke
angina Long-term prophylaxis of angina
Adverse effects Headaches
◦ Usually diminish in intensity and frequency with continued use
◦ Treated with acetaminophen Tachycardia, postural hypotension Tolerance may develop
Tolerance
Occurs in patients taking nitrates around the clock or with long-acting forms
Prevented by allowing a regular nitrate-free period to allow enzyme pathways to replenish
◦ Transdermal forms: remove patch at bedtime for 8 hours, then apply a new patch in the morning
Nursing implications
IV forms of NTG must be given with special non-PVC tubing and bags
Discard parenteral solution that is blue, green, or dark red
Follow specific manufacturer’s instructions for IV administration
Instruct patients in proper technique and guidelines for taking sublingual NTG for anginal pain
Instruct patients never to chew or swallow the SL form
Instruct patients that a burning sensation felt with SL forms indicates that the drug is still potent
Instruct patients to keep a fresh supply of NTG on hand; potency is lost in about 3 months after the bottle has been opened
Medications should be stored in an airtight, dark glass bottle with a metal cap and no cotton filler to preserve potency
Instruct patients in the proper application of nitrate topical ointments and transdermal forms, including site rotation and removal of old medication
To reduce tolerance, the patient may be instructed to remove topical forms at bedtime and apply new doses in the morning, allowing for a nitrate-free period
Instruct patients to take prn nitrates at the first hint of anginal pain
Monitor VS frequently during acute exacerbations of angina and during IV administration
If experiencing chest pain, the patient taking SL NTG should be lying down to prevent or decrease dizziness and fainting that may occur due to hypotension
If anginal pain occurs:
Stop activity and sit or lie down Take a SL tablet (as prescribed), If no relief of chest pain, call Emergency
Services/911 immediately Do not try to drive to the hospital
atenolol (Tenormin)
metoprolol (Lopressor)
propranolol (Inderal)
nadolol (Corgard)
Mechanism of action 1-receptors on the heart are blocked Decrease the HR, resulting in decreased myocardial
oxygen demand and increased oxygen delivery to the heart
Decrease myocardial contractility, helping to conserve energy or decrease demand
After an MI, a high level of circulating catecholamines irritate the heart, causing an imbalance in supply and demand ratio and even leading to life-threatening dysrhythmias. -blockers block the harmful effects of catecholamines, thus improving survival
Indications
Angina Antihypertensive Cardiac dysrhythmias Cardioprotective effects, especially after MI Some used for migraine headaches, essential
tremors, and stage fright
Adverse effectsBody System Adverse EffectsCardiovascular Bradycardia, hypotension,
second- or third-degree heart block; heart failure
Metabolic Altered glucose and lipidmetabolism
CNS Dizziness, fatigue, mental depression, lethargy,
drowsiness, unusual dreamsOther Impotence, wheezing,
dyspnea
Nursing implications Patients taking -blockers should monitor pulse rate daily
and report any rate lower than 60 beats per minute
Dizziness or fainting should also be reported
Constipation is a common problem; instruct patients to take in adequate fluids and eat high-fiber foods
These medications should never be abruptly discontinued due to risk of rebound hypertensive crisis
Inform patients that these medications are for long-term prevention of angina, not for immediate relief
Mechanism of action
Cause coronary artery vasodilation
Cause peripheral arterial vasodilation, decreasing systemic vascular resistance
Reduce the workload of the heart
Result: decreased myocardial oxygen demand
Indications
First-line drugs for treatment of angina, hypertension, and supraventricular tachycardia
Coronary artery spasms (Prinzmetal’s angina) Short-term management of atrial fibrillation and flutter Raynaud’s Phenomenon
Adverse effects
Very acceptable adverse effect and safety profile May cause hypotension, palpitations, tachycardia or
bradycardia, constipation, nausea, dyspnea (other adverse effects possible
Constipation is a common problem
Patients should: take in adequate fluids Eat high-fiber foods
Before administering, perform a complete health history to determine presence of conditions that may be contraindications for use or call for cautious use
Obtain baseline VS, including respiratory patterns and rate
Assess for drug interactions Patients should not take any medications,
including OTC medications, without checking with the physician
Patients – encourage to limit caffeine intake
Patients should report blurred vision, persistent headache, dry mouth, dizziness, edema, fainting episodes, weight gain of 2 pounds in 1 day or 5 or more pounds in 1 week, pulse rates less than 60, and any dyspnea
Alcohol consumption and hot baths or spending time in whirlpools, hot tubs, or saunas will result in vasodilation, hypotension, and the possibility of fainting
Teach patients to change positions slowly to avoid postural BP changes
Encourage patients to keep a record of their anginal attacks, including precipitating factors, number of pills taken, and therapeutic effects
Monitor for adverse reactions◦ Allergic reactions, headache, lightheadedness,
hypotension, dizziness
Monitor for therapeutic effects◦ Relief of angina, decreased BP, or both
A 62-year-old patient is having an anginal attack but avoids taking his prescribed PRN dosage of nitroglycerin.
Appropriate nursing actions would include:(Select all that apply.)
1. having him take the prescribed dose immediately.2. asking him why he avoids taking the dose as soon as the pain starts.3. giving him a thorough explanation of the purpose(s) or value of taking
the medication.4. reprimanding him severely for his hesitancy in self-administering thenitroglycerin
Instruct the patient on the proper storage of nitroglycerin to keep the medicine in:
1. a chest pocket for easy access. 2. its container for 6 months. 3. the original, dark-colored glass container. 4. its container in the refrigerator to reduce deterioration.
Calcium channel blockers reduce anginal pain by:
1. promoting vasodilatation and minimizingcellular aggregation.2. increasing the heart rate and bloodpressure.3. stimulating peripheral vasoconstriction.4. increasing peripheral resistance