Ischemic Heart Disease

This is referred to as silent ischemia. Blood supply to your heart may be restricted due to coronary artery disease, but you don’t feel any adverse effects.

If your coronary arteries can’t supply enough blood to meet the oxygen demands of your heart, the result may be chest pain called angina. People often describe the feeling of chest pressure or tightness as if somebody were pressing down on their chest. Angina can be caused by either physical or psychological stress. People usually experience relief from the pain within minutes of stopping the activity that caused it.

Some people may not be aware they have coronary artery disease until they develop symptoms of heart failure extreme fatigue with exertion, shortness of breath, and swelling in their feet and ankles. Heart failure occurs when your heart becomes so weakened from insufficient blood supply or from a heart attack that it can’t pump enough blood to meet your body’s needs.

When an artery supplying your heart muscle is completely blocked, it can lead to a heart attack. Unfortunately, the result of this blockage is that part of your heart muscle dies. A coronary artery might become narrowed over time, and this usually leads to a blockage resulting from a blood clot or other obstruction. Pain from a heart attack is often described as crushing and may feel similar to angina, but it lasts longer.

Atherosclerosis is a complex health disease that starts in childhood and usually progresses as you age. In some people, atherosclerosis progresses rapidly, especially those with risk factors such as smoking, high blood pressure, diabetes, and high cholesterol. Obesity and physical inactivity are other factors that can contribute to this disease.

A high blood level of low-density lipoprotein (LDL) cholesterol so-called “bad” cholesterol can lead to atherosclerosis. High blood cholesterol can be an inherited problem, but it’s also typically a byproduct of poor health habits such as eating a high-fat, high-cholesterol diet, which is common in Western societies. When the level of LDL cholesterol in your blood is high, there’s a greater chance that it will be deposited onto your artery walls. Higher levels of “good” cholesterol, high-density lipoprotein (HDL), seem to protect against heart disease.

Some research suggests that a bacterium, such as Chlamydia pneumonia, may play a role in the narrowing of coronary arteries. But whether infectious agents play an important role in this process isn’t well-defined because other research has failed to confirm this link. It’s also unclear whether inflammation of the arteries caused by an infection or other factor underlies coronary artery disease or accelerates it.

How can you know whether you have this silent, potential killer? Your doctor can help answer that question based on test results and your level of risk. If you have risk factors for coronary artery disease, your doctor may want to test you for coronary artery disease, even if you don’t have signs or symptoms of narrowed arteries. You may be referred to a cardiologist, a doctor who specializes in diagnosing and treating cardiovascular problems. The term cardiovascular refers to your body’s circulatory system your heart, arteries, and veins.

In addition to a physical examination, taking your medical history, and routine blood tests, your doctor may recommend these tests to diagnose coronary artery disease:

Electrocardiogram (ECG)

In this test, which is sometimes called an EKG, patches with wires (electrodes) are attached to your skin to measure electrical impulses given off by your heart. This test can show evidence of a previous heart attack or one that’s in progress. It can also yield other useful information, such as the status of your heart’s electrical system. ECG readings taken continuously over a period of 24 hours or longer may help detect silent ischemia.

This technique is called ambulatory electrocardiography monitoring, or Holter monitoring. Electrodes attached to your chest are connected to a portable monitor about the size of a paperback book or smaller that attaches to your belt or is carried by a shoulder strap. You wear the monitor for 24 hours as you go about your normal activities. Recorded abnormalities may show evidence of inadequate blood supply to your heart.

Echocardiogram

Through this examination, sound waves will be generated to create an image of your heart’s structure. An echocardiogram can help identify whether an area of your heart has been damaged from a lack of blood supply by assessing how well that area moves during each heartbeat. When combined with a stress test, an echocardiogram can also help identify areas of diminished blood flow to your heart.

Stress Test.

Stress tests help measure whether your heart is getting adequate blood supply. They may be used to evaluate symptoms such as chest pain or shortness of breath during exertion. Or if you have significant risk factors for coronary artery disease even if you have no symptoms a stress test can be used as a screening tool.

There are several kinds of stress tests. During an exercise stress test, you walk on a treadmill or pedal a stationary bike while an ECG records your heart’s response to an increasing workload. For people who can’t exercise, medication may be used to “stress” the heart and mimic the effects of exercise instead. Doctors also sometimes use imaging tests an echocardiogram or a nuclear scan to provide additional information by generating pictures of your heart during and after exercise or pharmacologic stress.

This has long been considered the definitive test for coronary artery disease. It can show specific sites of narrowing in coronary arteries. A small tube (catheter) is inserted into an artery in your arm or groin and threaded into your heart. A dye is injected into the catheter. As the dye flows through your coronary arteries, your doctor can see narrow areas and blockages with the help of X-rays.

This technique uses magnetic waves to produce a three-dimensional image of your coronary arteries to check for narrowings or blockages.

This technique is still being developed, but it has the advantage of producing images of your coronary arteries with a noninvasive procedure.

This test also helps identify blood flow problems in your heart. Trace amounts of radioactive material, such as thallium or a compound known as Cardiolite, are injected into your bloodstream. Special cameras can detect areas in your heart that receive less blood flow.

This test, also called an ultrafast CT scan, can detect calcium within plaques that narrow coronary arteries. Most, but not all, plaques contain some calcium. High calcium levels in the coronary arteries can be an indicator of coronary artery disease.

If your doctor finds that you have coronary artery disease, several treatment approaches are possible, depending on the seriousness of the disease. Coronary artery disease can be managed through lifestyle modifications and proper medication use. Other people with severe coronary artery disease may need coronary angioplasty or surgery.

Although great advances have been made in treating coronary artery disease, changing your habits remains the single most effective way to stop the disease from progressing. Here are the most beneficial changes you can make:

Don’t Smoke

Smoking is a major risk factor for coronary artery disease. Quitting smoking dramatically lowers your risk of a first or second heart attack.

Improve Your Diet

If you know that you have coronary artery disease, changing your diet to one low in fat, especially saturated fat and cholesterol will help reduce high blood cholesterol, a primary cause of atherosclerosis. It’s important to keep your cholesterol low after a heart attack to help lower your risk of having another one. Eating less fat should also help you lose weight. If you are overweight, reducing your weight can be an additional approach to optimizing your cholesterol levels. Eating a diet rich in fruits and vegetables and having at least one to two servings of fish a week also can reduce your risk of a heart attack.

Exercise Regularly

Even moderate amounts of physical activity 30 minutes a day can lower your risk of death from coronary artery disease. However, people with severe coronary artery disease may need to restrict their exercise somewhat. If you have coronary artery disease, check with your doctor to find out what kinds of exercise are best for you.

Cholesterol is a large part of the deposits that can narrow heart arteries. A high level of cholesterol in your blood increases your risk of coronary artery disease. Cholesterol-lowering drugs, also called lipid-lowering drugs, help lower the level of “bad” cholesterol in your blood while raising the level of “good” cholesterol. One type of cholesterol, HDL, actually helps protect against coronary artery disease. Examples of cholesterol-lowering drugs include statins, niacin, fibrates, and bile acid sequestrants.

Aspirin for Ischemic Heart Disease

Aspirin, as well as other blood thinners, can reduce the tendency of your blood to clot, which may help prevent obstruction of your coronary arteries.

Beta-Blockers

These drugs slow your heart rate and decrease blood pressure, which in turn decreases your heart’s demand for oxygen. Beta-blockers also have been shown to reduce the risk of death in people during and after a heart attack. In addition, they’re beneficial for people with weakened heart muscle and congestive heart failure.

Nitroglycerin

Nitroglycerin tablets, spray and patches can control chest pain (angina) by both opening up your coronary arteries and reducing your heart’s demand for blood.

Calcium Channel Blockers

These medications cause the muscles that surround your coronary arteries to relax and the vessels to open more, increasing blood flow to your heart. They also control high blood pressure.

Angiotensin-Converting Enzyme (ACE) Inhibitors

These drugs allow blood to flow from your heart more easily, decreasing your heart’s workload. ACE inhibitors are the mainstay treatment for congestive heart failure, which can be a complication of coronary artery disease.

Other Drugs That Lower Blood Pressure, Such as Diuretics

These medications help open up your blood vessels, including those to your heart, decreasing your heart’s workload.

You may need to take drugs for your heart indefinitely, or you may take medications temporarily until a risk factor for coronary artery disease is better under control.

Types of procedures to improve coronary blood flow (revascularization) include:

Percutaneous Coronary Intervention

Also known as angioplasty or stent placement, this is a common treatment for severe blockage of the coronary arteries. Only a small cut is required in your skin to put the catheter into the blood vessel. In this procedure, a doctor inserts a catheter with a small balloon at the tip into an artery in your groin or arm. The catheter is then threaded into the region of a coronary artery that’s narrowed. When the catheter reaches the blockage, the balloon is inflated to widen the artery and improve blood flow.

Stents

Often small wire tubes (stents) are placed into the area where the blockage occurred to keep the artery from narrowing again. In 2003, the
Food and Drug Administration approved the use of drug-eluting stents to help keep coronary arteries open. These stents are covered with a drug that has been shown to reduce the rate of new blockages. However, drug-eluting stents are not appropriate or necessary in all situations, and long-term results are still pending. If the percutaneous coronary intervention doesn’t widen the artery or if complications occur, you may need bypass surgery.

Coronary Bypass Surgery

This requires open heart surgery. It’s a procedure used to create a route for blood to go around a blocked stretch of a coronary artery. A blood vessel, usually taken from your leg or chest, is grafted directly onto a narrowed artery, bypassing the blocked area. In the event of multiple arteries being blocked, a bypass procedure can be carried out for each one. The blood can then go around the obstruction to supply your heart with enough blood to relieve chest pain.

Atherectomy

In this procedure, a catheter is inserted into an artery. The catheter is equipped with a diamond-shaped device that rotates up to 200,000 times a minute to shave plaques off your artery walls.

Research into new ways to treat coronary artery disease is yielding possibilities. Here are some areas of current research:

Radiation (Brachytherapy) Following Coronary Angioplasty

The majority of people who undergo coronary angioplasty for coronary artery disease receive small wire tubes (stents) to hold the arteries open longer. Stents are generally effective at keeping blood vessels open and wide enough for normal blood flow. Unfortunately, there are people who experience blockage again after undergoing coronary angioplasty. Researchers are studying whether treating narrowed coronary arteries with radiation at the time of angioplasty prevents new blockages from forming.