Heart Disease Tests and Medical Procedures

Over the course of your heart disease treatment, your doctor will order any of several tests and procedures. Some measure and subsequently keep track of your risk factors. Others measure directly the status of your heart. Some of the procedures in this latter group involve surgery, and since every invasive procedure entails a degree of risk.

It’s important for you and your family to learn as much about the procedure as you can. In this regard, a number of studies suggest that patients do better when they are treated at hospitals where many of these procedures, such as angioplasty or coronary artery bypass surgery, are performed each year.

Of course, the experience and skill of individual doctors can overcome this finding, but if you have a choice, you may choose to have such procedures done where the practitioners have the greatest experience.

Measuring and Tracking Risk Factors

In addition to checking your blood pressure regularly, your doctor may order any or all of the following tests or procedures.

Cholesterol and Triglycerides

About the test: Measures of your blood cholesterol level can be done at any time, but the most accurate measures are taken after you have fasted for twelve hours or so. That is why the test is often done in the morning before you eat breakfast. A complete cholesterol and triglycerides test, also known as a “lipid panel,” includes a measure of LDL (bad) cholesterol, HDL (good) cholesterol, total cholesterol, and triglycerides.

When to do the test: This test should be done every year or so if you do not have high “bad” cholesterol levels. For people being treated, the levels should be checked six weeks after starting a new cholesterol-lowering therapy and then every four to six months thereafter.

What the result mean: High LDL (bad) cholesterol, total cholesterol, and triglyceride levels and/or low HDL (good) cholesterol levels indicate that you have dyslipidemia a condition that needs to be treated with cholesterol-lowering medication.


About the test: A measure of your blood glucose (sugar) can be done at any time, but the most meaningful measure for the diagnosis of diabetes is taken after you have not eaten for about twelve hours. Both fasting and non-fasting (random) glucose tests can be done by some patients in their own homes using a glucometer (glucose measuring device).

When to do the test: People with heart disease should have their fasting glucose measured at least every two years. People with diabetes need to have fasting and random glucose levels checked more frequently up to a few times per day in some cases.

What the result mean: A fasting glucose level that is borderline high (between 110 and 126 mg/dL) should be monitored carefully. A fasting glucose level that is definitely high and that has been measured on at least two separate occasions means that you have diabetes and need to start diabetes therapies.

Hemoglobin A1c

About the test: A measure of the hemoglobin A1c level in your blood indicates how much glucose (sugar) your blood cells have been exposed to on average over the last two to four months. This test level stays relatively constant over time, so it won’t change as a result of a recent meal or medication just taken. Therefore, this is the best test for understanding how your glucose control has been over the longer term.

When to do the test: The test should be done every three months for people who have diabetes.

What the result mean: A high hemoglobin A1c level (7 percent or greater) means that your glucose levels have been on average higher than they should have been over the last few months. This means that your current strategy for controlling your glucose levels needs to be adjusted.

Blood Chemistry

About the test: Blood levels of key minerals and proteins are measured to monitor how certain blood pressure–lowering medications may be affecting the kidneys. The elements measured can include: sodium, potassium, chloride, bicarbonate, and more specific measures of kidney function called urea nitrogen and creatinine. These measures are also done to help monitor hypertension or heart failure.

When to do the test: These measures are checked before starting blood pressure–lowering medication and then periodically afterward. They may be done more frequently in people who have heart failure or who are being treated with diuretics. High potassium levels may be a particular problem for patients on ACE inhibitors or aldosterone antagonists.

What the result mean: Abnormal levels of the elements measured in blood chemistry can be a sign of wear on the kidneys as a result of high blood pressure, certain blood pressure medications, or heart failure.

Measuring and Tracking the Status of Your Heart Disease

You and your doctor will want to know whether your heart disease has gotten worse, stayed the same, or gotten better. The tests and procedures below are those that are most commonly used. You don’t need to have all of these tests done for your doctor to understand and effectively monitor the status of your heart disease.


About the test: Also known as an EKG or ECG, this is a painless and noninvasive test used to record the pattern of electrical currents generated by the heart. Wires are placed across your chest and on each of your limbs to pick up the electrical activity. All you need to do is lie flat for a few minutes.

When to do the test: An ECG test is often done when there is a change in the symptoms or signs of heart disease and sometimes just for monitoring purposes. An ECG is also often done if there is a suspicion that the heart is beating at an unusual rate or rhythm.

What the result mean: Different patterns from an ECG tracing can show that a part of the heart is not getting enough blood supply, that there has been a heart attack in the past, or that the heart rate or rhythm has unusual features. However, an ECG tracing can also appear normal in people who have heart disease which is why other diagnostic tests are often needed.

Holter Monitoring

About the test: Also called “ambulatory ECG,” this test is like an ECG test, only instead of getting a heart tracing over a few minutes, a similar monitoring device is worn by the patient for at least twenty-four hours while performing daily activities and a continuous heart tracing is recorded over this period of time. This test is also called a “Holter monitor,” named for the person who developed it.

When to do the test: A Holter test is often done if a patient has fainted or has unexplained episodes of feeling light-headed, dizzy, or weak, or of palpitations. The test can show if these symptoms are related to periods of abnormal heart rate or rhythm over the course of a day.

What the result mean: The results can indicate conditions that need further evaluation or treatment based on the heart’s electrical activity.

Exercise Stress Test

About the test: This is a noninvasive test that involves wearing wires connected to a machine that monitors heartbeat, blood pressure, and ECG tracing while the patient performs various levels of exercise on a treadmill or stationary bicycle.

When to do the test: An exercise stress test is done to help make the diagnosis of heart disease for people who experience chest pain or difficulty breathing. For people who already have heart disease, the test can help determine how serious the condition is.

What the result mean: This test can help determine whether your heart is receiving an adequate blood flow during exertion. Doctors evaluate how long you can exercise, what happens to your heart rate and blood pressure during exertion, whether you develop any symptoms, whether your electrocardiogram shows important changes, and how your heart rate recovers after you finish.

This test helps the doctor know whether your risk of future heart disease is high and whether additional tests might be useful to you. Sometimes, particularly for people with difficult-to-interpret electrocardiograms, pictures of the heart are taken.


About the test: This is a painless, noninvasive but effective way to see what your heart looks like and how it is working. Some lubricant jelly is placed on your chest and then a special ultrasound probe is rolled along the jelly to take both moving and snapshot pictures of your heart as you lie still.

Another type of ultrasound test that is done less commonly involves swallowing a smaller ultrasound probe in order to obtain better pictures of your heart. Patients usually receive medication to relax them for this test. It is called a transesophageal echocardiogram (TEE) and is much less frequently required.

The advantage of TEE is that the pictures are much better, and it is only required when the other ultrasound test does not provide good enough pictures for what the doctor is trying to see.

When to do the test: Echocardiography is often done when there is a change in the symptoms or signs of heart disease. An echocardiogram can be done to assess an enlarged heart, abnormal sounds (such as murmurs), unexplained chest pain, difficulty breathing, palpitations, and stroke (which can be caused by blood clots from the heart). An echocardiogram can also be combined with an exercise test to evaluate blood flow to the heart.

What the result mean: The results of an echocardiogram can help confirm the diagnosis of heart disease, measure the ability of the heart to do its job of pumping blood to the rest of the body, and indicate whether there are any abnormalities of the heart valves or heart walls.

Nuclear Scan

About the test: During this test, a small amount of radioactive substance (such as thallium or technium) is injected into your bloodstream. Although it is radioactive, the dose is so small that it is not considered dangerous, even for people who have this test many times over their lifetime.

As the substance travels to the arteries that supply blood to your heart muscle, a camera scans the amount of the radioactive substance reaching different parts of the heart muscle while you exercise. The distribution of the substance can tell the doctors about the blood flow to your heart.

If it is not possible for you to exercise, another substance is injected to simulate exercise-like stress on the heart while the scan is being done. The stress medication may cause you to have some discomfort (e.g., headache, nausea, chest pain, shortness of breath) for a few minutes, but these symptoms should not last long.

After the exercise or stress-medication part of the test is done, you will usually be asked to rest for about four hours before another scan is done. The two scans are then compared to identify the size and location of poor blood supply or damage to your heart muscle.

When to do the test: A nuclear scan is similar to an exercise stress test but provides more information about blood flow through the coronary arteries. Your doctor may order a nuclear scan if you have worsening symptoms and more information is needed about the condition of your heart and particularly when the electrocardiogram has certain patterns that are difficult to interpret in an exercise test.

What the result mean: A nuclear scan can show if a part of your heart that is deprived of blood supply during exercise can recover after rest this result would suggest narrowed arteries. If an area of the heart does not get any blood supply during exercise and does not recover after rest, this area is likely to have scar tissue left over from a previous heart attack.

Electron-Beam Computerized Tomography

About the test: Also known as EBCT or a CT artery scan, this test involves taking pictures of the arteries that supply the heart to determine whether there are any areas of blood vessel hardening and narrowing. Arteries that are hardened and narrowed by heart disease will have calcium deposits in the vessel walls, and this is what the computerized tomography (CT) scan picks up.

All the patient has to do is lie still in the CT scanner while it takes high-resolution pictures of the heart. Since this test is relatively new, the American Heart Association/American College of Cardiology are waiting for more studies of its use before fully recommending this test to help diagnose heart disease.

When to do the test: Although not yet widely used, this test is done to help diagnose heart disease, especially if the patient does not yet have symptoms. Because the test is simple to perform, it may be used more in the future as a way to screen for narrowed or blocked major arteries of the heart in people who have a high risk for heart disease.

What the result mean: Pictures taken during this test will show whether one or more of the major arteries of the heart is hardened or narrowed by heart disease.

Electrophysiology Test

About the test: Heart disease makes some people’s hearts more prone to beating with an irregular rhythm or rate (arrhythmia). Also known as an EP study or EP testing, electrophysiology testing is used to help diagnose this condition, especially if it is not obvious from other testing.

The test involves threading a small wire into the heart in the same way as is done during a cardiac catheterization. Once the tip of the wire is in the heart, it can then be used to directly stimulate and record electrical signals made by the heart and to perform tests from various locations inside the heart. If needed, the area causing the irregularity can be targeted for special treatment or a pacemaker can be placed in the heart at the time of the test.

When to do the test: This test is done when it is suspected that a person’s heart may be beating with a dangerous rhythm. Sometimes the clue is fainting episodes or episodes of rapid or slow heart rates (which can be associated with a fluttering feeling inside one’s chest).

What the result mean: The results of the test indicate whether a person’s heart is prone to beating irregularly, and if so, what kind of an irregularity (arrhythmia) it is. This helps determine how it should be treated.

Cardiac Catheterization

About the test: This test and procedure is also known as a “coronary angiogram.” A small amount of numbing medication is placed in your groin or arm and a thin, flexible tube (catheter) is inserted at that site and then guided painlessly up to the coronary arteries (the blood vessels that supply blood to your heart muscle).

A dye is then injected through the tube and, as the dye flows into and through the coronary arteries, X-ray video pictures are taken. Many people feel a brief warm or hot sensation in their chest from the dye.

When to do the test: This procedure is done if a patient experiences new or worsening symptoms, suggesting that there is not enough blood and oxygen reaching the heart muscle. The catheterization may also be done after a positive exercise or nuclear test.

What the result mean: Pictures taken during this procedure will show whether one or more of the major arteries supplying the heart muscle with blood is narrowed or blocked. If a major artery is found to be narrowed, your doctor may decide that angioplasty with or without stenting should be done at that moment to widen the area of narrowing. Certain findings may suggest the need for surgery.

Percutaneous Coronary Interventions

About the procedure: These interventions, also known as PCI, include angioplasty and stenting and are often performed in the same way as a cardiac catheterization. During angioplasty, a doctor threads a small deflated balloon through the catheter to the site of coronary artery narrowing.

The balloon is then inflated with air, causing the plaque that is narrowing the vessel to be flattened against the vessel wall and allowing more room for blood to flow through. As the balloon is inflated, you may feel some angina-like discomfort which you should tell your doctor about at that time.

The balloon is then deflated. Stenting is often done next. A coronary stent is a special expandable mesh tube that is placed over the deflated balloon. The balloon is then inflated one more time so that the stent expands and is fitted into the artery wall against the flattened plaque.

The balloon is then deflated and removed while the stent is left in place to keep the artery propped open. Some new types of stents, called “drug-eluting stents,” slowly release a medication that helps to keep an artery from reclosing after the stent is put in place.

When to do the procedure: These interventions can be done during a cardiac catheterization when the pictures show an area of vessel narrowing. Angioplasty with or without stenting can also be done if you are having a heart attack, to rapidly restore blood flow to the heart.

What is the result: When used during a heart attack, these interventions can return blood flow to an area of the heart that might otherwise become damaged and scarred. In non–heart attack situations, angioplasty can improve angina and related symptoms of heart disease.

Stenting lowers the risk that the area of the coronary artery will reclose. How well angioplasty and stenting work to prevent future heart problems or prolong life is still being studied. It seems that they are most useful for improving quality of life.

Coronary Artery Bypass Grafting Surgery

About the procedure: Also known as CABG (pronounced “cabbage”) or “bypass surgery,” this is a major operation done under general anesthesia, and it usually lasts anywhere from two to six hours. During the operation, a piece of vein from your leg or an artery from your chest is used to reroute or bypass blood around a blocked segment of artery. It may be done by opening the chest, though occasionally only a small incision is made in the chest (in what is called “minimally invasive surgery”).

When to do the procedure: If angioplasty is unsuccessful or if cardiac catheterization shows that the artery blockage is too complex for angioplasty, or if you have severe blockages in many major arteries, your doctor may recommend bypass surgery. Bypass surgery is also recommended instead of angioplasty for many people with diabetes.

What is the result: Bypass surgery is not a cure for heart disease. As with angioplasty, bypass surgery works to improve heart disease symptoms and potentially reduce your risk of future heart problems. It is useful to know if this surgery is being recommended to you to improve the quality of your life or to increase the length of your life.

Only certain types of patients are thought to derive survival benefit from CABG; for most people the surgery is primarily to improve the quality of their life.