Antianginal Drugs Overview

Study Notes

Balance: Myocardial oxygen supply needs to balance with demand. Coronary arteries supply oxygen.
Angina Pectoris: Chest pain due to insufficient oxygen supply to the myocardium.
- Stable: Caused by atherosclerosis, worsened by exertion, relieved by rest or medication.
- Unstable: Shows early signs of Coronary Artery Disease (CAD), unpredictable, and can lead to a heart attack (MI).
Ischemia: Cellular/tissue damage due to inadequate blood supply
Atherosclerosis: Plaque buildup in artery walls, causing narrowing.
CAD: Atherosclerosis in the coronary arteries
Myocardial Infarction (MI): Blockage of blood flow to the heart muscle, leading to tissue death.
Classes of Antianginal Drugs:
- Nitrates
- Beta Blockers
- Calcium Channel Blockers
- Ranolazine (newest, unknown mechanism)

Mechanism: Dilate coronary arteries, increasing blood flow and oxygen.
Example Drugs: Nitroglycerin (IV, ointment, spray, sublingual, transdermal patch), Isosorbide dinitrate (PO), Isosorbide mononitrate (PO)
Contraindications: Severe anemia, hypotension, erectile dysfunction drugs.
Side Effects: Low blood pressure, headaches.

Mechanism: Decrease heart rate and oxygen demands, decrease risk of dysrhythmias, improve survival after a heart attack (MI).
Example Drugs: Carvedilol, metoprolol, atenolol
Contraindications: bradycardia, hypotension.
Nursing Considerations: Do not stop abruptly to avoid rebound effect of tachycardia.

Mechanism: Work in different ways to relax smooth muscles, leading to arterial dilation.
Example Drugs: Amlodipine, nifedipine (Dihydropyridines), diltiazem, verapamil (Benzothiazepines and phenylalkylamines).
Dihydropyridines: Relax arterial smooth muscles but don't affect cardiac conduction.
Benzothiazepines/Phenylalkylamines: Reduce myocardial contractility, affect SA and AV node conduction (also antidysrhythmic effects).

Monitor Vital Signs (VS) and Labs.
Assess Patient.
Desired Outcomes: Reducing chest pain.
Medication Interactions: Important to note and monitor.
Do Not Stop Abruptly: Take as prescribed.
Ranolazine: Reserved for patients who have not benefited from other antianginal drugs; may cause cardiac dysrhythmias.

Nursing considerations include patient education, monitoring for adverse effects, avoiding abrupt discontinuation, and recognizing potential complications like worsening heart failure.
Important monitoring points include heart rate, rhythm, blood pressure, desired outcomes (like maintaining chest pain relief), and recognizing worsening heart failure symptoms.