When angina is mentioned, the classical picture that comes to mind is a chronic, slowly debilitating condition related to fat plaques clogging the arteries and causing a gradual obstruction. This idea is not wrong in most cases; however, a particular type of angina is very different from this, and is called Prinzmetal’s or Variant angina. Dr. Myron Prinzmetal first discovered it as a syndrome featuring chest pain found in a patient who can tolerate usual physical exercise. On the other hand, he had a chest pain that is “triggered” usually early in the morning.
Why does it happen?
Unlike stable angina, the heart’s blood vessels’ caliber, “the coronaries,” is typical in between attacks. The pathology here is that the smooth muscles of the blood vessels walls reversibly contract, narrowing the blood vessels’ diameter suddenly and causing a marked decrease of blood flow, thereby inducing pain.
You should also know that this doesn’t mean that the coronary arteries are always in a state of relaxation. Instead, they are in a state of continuous, yet varying degrees of contraction finely tuned according to the body’s condition and needs. Any imbalance of the various chemical substances controlling such process induces spasm. When the spasm occurs, it varies from a mild spasm, in which pain can only be produced if the heart is exerted enough that the supply no longer matches the demand, to a severe spasm that may cut off the blood supply entirely from a part of the heart, leading to a heart attack -also known as myocardial infarction-. The provoking factors for these spasms are various, and although they are still not largely known, some known factors include:
- Tobacco smoking
- Hyperventilation
- Cocaine use
- Drugs as amphetamines
- Alcohol
- Cold exposure
Although the presence of coronary spasms doesn’t mean that the coronary artery itself is atherosclerotic, the presence of both types of angina is possible. The only known common risk factor between the two types is smoking, and cessation of smoking can prevent and potentially help treat both types. To summarize the main difference between stable angina and Prinzmetal’s, we can say that while stable angina is a demand problem, Prinzmetal’s angina is a supply problem.