Stable angina is pain, pressure, or a sense of heaviness or discomfort in the chest beneath the breastbone. It is usually brought on by physical exertion and relieved by rest. The discomfort or pain may also be felt in the left arm or shoulder, the neck, or the lower jaw.
What is going on in the body?
Atherosclerosis, or hardening of the arteries, is a condition in which fatty deposits, also called plaque, form inside blood vessel walls. Atherosclerosis that involves the arteries supplying the heart is known as coronary artery disease.
Plaque can block the flow of blood through the arteries. The tissues that normally receive blood from these arteries then begin to suffer damage from a lack of oxygen. When the heart does not have enough oxygen, the heart muscle reacts by causing the pain or discomfort known as angina.
What are the causes and risks of the condition?
Factors that increase the risk of stable angina include:
high blood pressure
high blood LDL "bad" cholesterol
low blood HDL "good" cholesterol
postmenopausal status in women
- lack of exercise
What can be done to prevent the condition?
A person may reduce the risk for developing stable angina by:
- not smoking
- lowering high blood pressure
- controlling blood cholesterol (especially the LDL component)
- controlling diabetes
- exercising regularly
- eating a diet designed to minimize heart disease
How is the condition diagnosed?
Stable angina is usually diagnosed by a history of chest discomfort that is caused by exertion but goes away with rest. A physical exam may reveal signs of hardening of the arteries. An electrocardiogram (ECG) is a recording of the heart's electrical activity. An ECG is usually normal when a person has no pain, and it shows certain changes when pain develops
An ECG done during exercise will show similar changes even before angina develops. A cardiac catheterization, or coronary angiogram, is a procedure that is used to look for narrowed coronary arteries. A contrast agent is injected into an artery and X-rays are then taken. This procedure can be used to find narrowed blood vessels supplying the heart.
Experts disagree about who should undergo a cardiac catheterization. It may be useful for:
a person who has angina that affects his or her ability to lead a normal life
someone who is young with multiple risk factors for heart disease and an abnormal stress test.
someone with a heart attack
someone whose diagnosis is not clear
- someone who has an abnormal stress test and has symptoms of angina
Long Term Effects
What are the long-term effects of the condition?
If untreated, atherosclerosis can lead to stable angina brought on by lower and lower levels of exertion. Unstable angina, a severe, progressive angina that medication cannot control, can occur next. Other long-term effects include congestive heart failure, heart attack, and arrhythmias (irregular heartbeats).
What are the risks to others?
Stable angina is not contagious and poses no risk to others.
What are the treatments for the condition?
Several types of medications are often used in combination to reduce the symptoms of stable angina.
Beta-blockers, such as atenolol (i.e., Tenormin) or metoprolol (i.e., Toprol XL, Lopressor), are used to decrease the work level of the heart, so that the same effort requires less oxygen.
Nitrates, such as nitroglycerin or isosorbide mononitrate (i.e., Imdur, ISMO, Monoket), help to expand the small arteries and veins. This improves the blood flow to the heart.
- Aspirin may prevent heart attacks. Warfarin (i.e., Coumadin) may prevent blood clots. However, its use in treating stable angina remains controversial
Calcium channel blockers, such as diltiazem (i.e., Cardizem, Cartia XT, Dilacor XR, Dilt-CD, Diltia XT, Taztia XT, Tiazac), nifedipine (i.e., Procardia, Adalat CC), or verapamil (i.e., Calan, Covera-HS, Isoptin, Verelan), have been used for over 20 years to open the coronary arteries and lower high blood pressure. However, the findings of 2 recent studies have shown that people who take a calcium channel blocker have a much higher incidence of complications than people taking other medications for coronary artery disease and high blood pressure.
One study, for example, showed that the risk of heart attack was 27% greater and the risk of congestive heart failure was 26% higher for those taking a calcium channel blocker. The American Heart Association recommends discussing risks and benefits of the medication with the healthcare professional.
Clopidogrel (i.e., Plavix), a very potent platelet inhibitor, may be used for chronic angina or in cases of an acute coronary syndrome <new onset of severe angina>.
Several procedures can be used to reduce the symptoms of stable angina, including:
angioplasty, a procedure in which a tube with a balloon is inserted into the blocked artery and inflated. This reopens the artery and allows blood to flow.
placing a stent, a rigid tube similar to a tiny drinking straw, into the artery at the reopened area to keep it from narrowing again
atherectomy, which involves removing plaque that causes narrowing of a blood vessel
- open heart surgery, if the coronary stenting procedure is not a viable option
What are the side effects of the treatments?
Beta-blockers can cause:
- a slow heartbeat
- low blood pressure
- erectile dysfunction
- unpleasant dreams
Calcium channel blockers can cause:
- swelling of the ankles
- low blood pressure
- a higher risk of heart attack and congestive heart failure in certain ones, but not all
Nitrates can cause headaches and low blood pressure. Aspirin, warfarin, and clopidogrel increase the risk of bleeding. Surgery can be complicated by infection, bleeding, or reactions to anesthesia.
What happens after treatment for the condition?
Most individuals with stable angina are encouraged to begin a regular exercise program. A person with stable angina should make every effort to reduce coronary risk factors. This may include smoking cessation, control of other diseases such as diabetes
and high blood pressure, and following a healthy diet for heart disease
prevention. Medications may need to be adjusted to achieve the best response.
How is the condition monitored?
The person will have periodic examinations and tests by the healthcare professional to discuss episodes of stable angina. Any new or worsening symptoms should be reported to the healthcare professional.