Nursing Pharmacology: Antianginal Drugs

Nursing Pharmacology Chapter 9: Antianginal Drugs

"Cardiac |Angina for NCLEX RN"

Attribution:
- Linares M, RN Cardiac | Angina for NCLEX RN
- https://www.youtube.com/watch?v=XEu8x-4Q1QA
- Simple Nursing
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Definition: Angina are those symptoms of myocardial ischemia that occur when myocardial oxygen availability is insufficient to meet myocardial oxygen demand.
- Symptoms include:
  - Chest discomfort often described as heaviness, pressure, and squeezing. The sensation is localized typically in the sternal region.
  - Symptoms often last one to five minutes. Angina can radiate to the left shoulder, to both arms (ulnar surfaces of the forearm and hand), and can radiate to the neck, jaw, teeth, epigastrium and back.
  - In classical angina these symptoms often occur with exertion and are not due to sudden-onset vasospasm.
  - By contrast, in variant or Prinzmetal's angina which is caused by coronary vasospasm, reduction of coronary blood flow with angina may occur at rest.
- Myocardial ischemia is usually caused by coronary vessel atherosclerosis.
  - As the vessel lumen narrows blood flow is reduced.
    - Other causes that limit coronary blood flow include:
      - Arterial thrombi
      - Spasm
- The extent of coronary vessel obstruction can vary as a function of vascular tone: ranging from spasm resulting in 90% obstruction to intermediate effects.
- Coronary vasospasm that results in significant obstruction is the basis for Prinzmetal's variant angina.
  - If the plaque size results in less than about 50% reduction, sufficent coronary blood flow during exertion is still available and anginal symptoms are not present.

Prinzmetal's variant angina
This figure illustrates coronary artery vasospasm. In the top frame a localized narrowing of a long segment of the proximal right coronary artery is apparent. The patient had been complaining of intermittent chest pain during at rest. In the bottom frame the abnormality has been corrected by intracoronary nitroglycerin. The response to nitroglycering confirms that the narrowing resulted from coronary vasospasm or Prinzmetal's angina. [Timmis, A.D. In Pocket Picture Guides: Cardiology, Gower Medical Publishing, London, 1985, p.21]

[Raehl, C.L., and Nolan, P.E. Ischemic Heart Disease: Anginal Syndromes in Applied Therapeutics: The Clinical Use of Drugs (Young, L.Y., and Koda-Kimble, M.A., eds), Applied Therapeutics, Inc., Vancouver, 1995, p 13-3.]