Your Online Health Information Site




General, angina is a heart condition where the coronary arteries show a certain amount of narrowing and one area of the heart muscle gets less blood (less nutrients and oxygen).

In this case, this leads to a built up of lactic acid resulting in chest pain, which might radiate into the left arm and/or into the mid upper abdomen. To clarify, with rest these angina pains disappear (Ref. 2, p. 1273). Frequently, nitroglycerin tablets or spray will often be very useful in treating this condition as it releases nitric oxide (=NO) in the body that widens arteries and lowers blood pressure.

However, such symptoms are an alarm sign that this person should be investigated for risk factors. To emphasize, if you experience these signs, you would start by seeing your family doctor. The family doctor might investigate himself or send you on to a cardiologist. In particular, some of the tests that likely will be performed are an electrocardiogram(ECG), a fasting cholesterol level (total and HDL cholesterol) and perhaps an exercise stress test or a thallium stress test.

Risk factors for angina

In addition, risk factors are also evaluated as cigarette smoking, a lack of physical activity and a family history of heart attacks or premature deaths etc. are all important to know. Certainly, a thorough examination including a careful auscultation of the heart (listening to the heart sounds with the stethoscope) would complete the examination. Finally, the cardiologist may decide that an angiography is necessary. In this case the specialist introduces a catheter through the femoral artery back into the aorta. At the origin of the aorta right after the left heart chamber a dye can be injected into the opening of the coronary arteries to visualize them. Cardiologists talk about the number of lesions in a coronary artery and how advanced they are.

Example of occluded coronary arteries

For instance: a 60% occluded coronary artery would have clogged more than half of the opening slowing down blood flow through it considerably. Here is a link showing the heart catheterization technique (YouTube link) with an approach through the arm or through the leg. Usually there is the process of atherosclerosis present where fat deposits narrow the coronary arteries. However, with high blood pressure out of control there may be a process of arteriosclerosis present where the lining of the artery (intima) and the muscle envelope of the artery (media) are hard and stiff. Both processes (atherosclerosis and arteriosclerosis) can decrease the blood flow to the heart muscle and cause angina pain.



Unstable angina

The arteriosclerotic process may persist. In this case the previously stable angina, which affected only one of the three coronary arteries can spread. Now there may be a two or three vessel disease. This is diagnosed as “unstable angina“. Patients with unstable angina are at a high risk for developing serious complications such as an MI , heart arrhythmia or sudden congestive heart failure. In simple terms the heart is not able to do its proper job. The patients who require an urgent appointment to see a cardiologist are at a high risk for sudden cardiac death.

Fortunately in the last few decades there were great advances with regard to stents and by-pass surgery.


We have now access to specialized cardiologists who do a procedure called angioplasty where right after the angiogram a catheter with a expandable stent is introduced to the narrowed segment of the coronary artery and a 70 or 80% lesion is opened up completely. The stent stays behind and ensures that the previously narrowed coronary artery stays open after the angioplasty has been done.

Occasionally there might be a lesion which is too advanced to do angioplasty or angioplasty might fail. In this case a cardiovascular surgeon can do a heart by pass surgery.  The chest surgeon uses an artery from the chest wall (the internal mammary artery) to over-bridge the clogged coronary artery. Both angioplasty and heart by pass surgery are relatively safe procedures. They can add 10 to 15 years of life to patients with severe angina or unstable angina.



1. The Merck Manual, 7th edition, by M. H. Beers et al., Whitehouse Station, N.J., 1999. Chapters 197, 202, 205 and 207.

2. Braunwald: Heart Disease: A Textbook of Cardiovascular Medicine, 6th ed., 2001, W. B. Saunders Co.

3. D C Bauer: Audio-Digest Family Practice Vol. 49, Iss. 09, March 2, 2001.

4. Ferri: Ferri’s Clinical Advisor: Instant Diagnosis and Treatment, 2004 ed., Copyright © 2004 Mosby, Inc.

5. Rakel: Conn’s Current Therapy 2004, 56th ed., Copyright © 2004 Elsevier

Last modified: March 29, 2020

This outline is only a teaching aid to patients and should stimulate you to ask the right questions when seeing your doctor. However, the responsibility of treatment stays in the hands of your doctor and you.