Frequently Asked Questions Part I | Part II | Part III

How Should I Prepare for the Test?

  • Avoid oily or greasy skin creams and lotions the day of the test. They interfere with the electrode-skin contact.
  • Avoid full-length hosiery, because electrodes need to be placed directly on the legs.
  • Wear a shirt that can be easily removed to place the leads on the chest.

What Happens During the Test?
During the procedure, a technician will attach 10 electrodes with adhesive pads to the skin of your chest, arms and legs. Men may have chest hair shaved to allow a better connection. You will lie flat while the computer creates a picture, on graph paper, of the electrical impulses traveling through your heart. This is called a "resting" EKG. This same test may also be used to monitor your heart during exercise.

It takes about 10 minutes to attach the electrodes and complete the test, but the actual recording takes only a few seconds.

Your EKG patterns will be kept on file for later comparison with future EKG recordings.
If you have questions, be sure to ask your doctor.
In addition to the standard EKG, your doctor may recommend other specialized EKG tests, including holter monitor or a signal-averaged electrocardiogram.

What Is Holter Monitor?
Holter monitor is a portable EKG that monitors the electrical activity of a freely moving person's heart for one to five days, 24-hours a day. It is most often used when the doctor suspects an abnormal heart rhythm or ischemia (not enough blood flow to the heart muscle).
It is a painless test; electrodes from the monitor are taped to the skin. Once the monitor is in place, you can go home and perform all of your normal activities (except showering). You will be asked to keep a diary of your activities and any symptoms you experience and when they occur.

What Are the Types of Echocardiograms?

  • Transthoracic echocardiogram: This is the standard echocardiogram. It is a painless test similar to X-ray, but without the radiation. The procedure uses the same technology used to evaluate a baby's health before birth. High frequency sound waves (ultrasound) are bounced off the heart structures (using a device called a transducer) producing images and sounds that can be used by the doctor to detect heart damage and disease.
  • Transesophageal echocardiogram (TEE): This test requires that the transducer be inserted down the throat into the esophagus (the swallowing tube that connects the mouth to the stomach.) Because the esophagus is located close to the heart, clear images of the heart structures can be obtained without the interference of the lungs and chest.
  • Stress echocardiogram: This is an echocardiogram that is performed while the person exercises on a treadmill or stationary bicycle. This test can accurately visualize the motion of the heart's walls and pumping action when the heart is stressed; it may reveal a lack of blood flow that isn't always apparent on other heart tests. The echocardiogram is performed just prior and just after the exercise.

How Should I Prepare for the Echocardiogram?
On the day of the test, eat and drink as you normally would. Take all of your medications at the usual times, as prescribed by your doctor.

What Happens During the Echocardiogram Test?
During the test, you will be given a hospital gown to wear. You will be asked to remove your clothing from the waist up. A cardiac sonographer will place three electrodes (small, flat, sticky patches) on your chest. The electrodes are attached to an electrocardiograph monitor (ECG or EKG) that charts your heart's electrical activity.

The sonographer will ask you to lie on your left side on an exam table. He or she will place a wand (called a sound-wave transducer) on several areas of your chest. The wand will have a small amount of gel on the end, which will not harm your skin.

Sounds are part of the Doppler signal. You may or may not hear the sounds during the test. You may be asked to change positions several times during the exam in order for the sonographer to take pictures of different areas of your heart.

You should feel no major discomfort during the test. You may feel coolness from the gel on the transducer and a slight pressure of the transducer on your chest.

The test will take about 40 minutes. After the test, you can get dressed and go about your daily activities.

What Should I Do to Prepare for a Stress Echo?
On the day of the test, do not eat or drink anything except water for four hours before the test.

Do not take the following heart medications on the day of your test unless your doctor tells you otherwise: Beta-blockers (for example, Tenormin, Lopressor, Toprol, or Inderal); Isosorbide dinitrate (for example, Isordil, Sorbitrate); Isosorbide mononitrate (for example, Ismo, Indur, Monoket); Nitroglycerine (for example, Deponit, Nitrostat, Nitropatches). Your doctor may also ask you to stop taking other heart medications on the day of your test. If you have any questions about your medications, ask your doctor. Do not discontinue any medication without first talking with your doctor.

What Should I Do if I Have Diabetes?

  • If you take insulin to control your blood sugar, ask your doctor what amount of your medication you should take the day of the test. Often, your doctor will tell you to take only half of your usual morning dose and to eat a light meal four hours before the test.
  • If you take pills to control your blood sugar, do not take your medication until after the test is complete.
  • Do not take your diabetes medication and skip a meal before the test.
  • If you own a glucose monitor, bring it with you to check your blood sugar levels before and after your test. If you think your blood sugar is low, tell the lab personnel immediately.
  • Plan to eat and take your blood sugar medication following your test.

What Happens During the Test?
First, a technician will gently rub 10 small areas on your chest and place electrodes (small, flat, sticky patches) on these areas. The electrodes are attached to an electrocardiograph monitor (ECG or EKG) that charts your heart's electrical activity during the test.

An intravenous line (IV) will be inserted into a vein in your arm so dobutamine medication can be delivered directly into your bloodstream. The technician will perform a resting EKG, measure your resting heart rate and take your blood pressure. The doctor or nurse will administer the dobutamine into the IV while the technician continues to obtain echo images. The medication will cause your heart to react as if you were exercising.

At regular intervals, the lab personnel will ask how you are feeling. Please tell them if you feel chest, arm or jaw pain or discomfort; short of breath; dizzy; lightheaded or if you have any other unusual symptoms.

The lab personnel will watch for any changes on the ECG monitor that suggest the test should be stopped. The IV will be removed from your arm once all of the medication has entered your bloodstream.

The dobutamine may cause a warm, flushing feeling and in some cases, a mild headache. If you begin to notice these symptoms or other symptoms of concern such as chest discomfort, excessive shortness of breath or irregular heartbeats, tell the lab personnel immediately.

The appointment will take about 60 minutes.

What Happens During the Transesophageal Echo?
Before the test, you will be asked to remove dentures and lie down on your left side on the exam table. You will be given some intravenous fluids and a mild sedative (medicine to help you relax). Your heart rate and blood pressure will be monitored throughout the procedure. Finally, an anesthetic spray is sprayed into the throat to reduce the gag reflex.

Then a small transducer attached to along tube is inserted into the esophagus via the mouth. This won't affect breathing, but swallowing may be temporarily affected. Next the doctor will perform the test to visualize the heart.

When completed, the tube is withdrawn. Vital signs will be monitored for about 20-30 minutes. You cannot eat or drink until the anesthetic spray wears off -- about an hour.

The test takes about 90 minutes to perform.

You will need to arrange transportation home since you may feel groggy from the sedative.

What Are the Symptoms of Arrhythmias?
An arrhythmia can be silent and not cause any symptoms. A doctor can detect an irregular heartbeat during a physical exam by taking your pulse or through an electrocardiogram (ECG).

When symptoms occur, they may include:

  • Palpitations (a feeling of skipped heart beats, fluttering or "flip-flops," or feeling that your heart is "running away").
  • Pounding in your chest.
  • Dizziness or feeling light-headed.
  • Fainting.
  • Shortness of breath.
  • Chest discomfort.
  • Weakness or fatigue (feeling very tired)

How Are Arrhythmias Diagnosed?
Tests used to diagnose an arrhythmia or determine its cause include:

  • Electrocardiogram
  • Ambulatory monitors.
  • Holter monitor.
  • Transtelephonic monitor.
  • Transtelephonic monitor with memory loop.
  • Stress test.
  • Echocardiogram.
  • Cardiac catheterization.
  • Electrophysiology study (EPS).
  • Head-up tilt table test.

How Are Arrhythmias Treated?
Treatment depends on the type and seriousness of your arrhythmia. Some people with arrhythmias require no treatment. For others, treatments can include medication, making lifestyle changes and undergoing surgical procedures.

What Medications Are Used to Treat Arrhythmias?
A variety of drugs are available to treat arrhythmias. These include:

  • Antiarrhythmic drugs. These drugs control heart-rate, and include beta-blockers.
  • Anticoagulant or antiplatelet therapy. These drugs reduce the risk of blood clots and include warfarin (a "blood thinner") or aspirin.

Because everyone is different, it may take trials of several medications and doses to find the one that works best for you.

What Is Electrical Cardioversion?
If drugs are not able to control a persistent irregular heart rhythm (such as atrial fibrillation), cardioversion may be required. After administration of a short-acting anesthesia, an electrical shock is delivered to your chest wall that synchronizes the heart and allows the normal rhythm to restart.

What Is Heart Surgery?
Heart surgery may be needed to correct heart disease that may be causing the arrhythmia. The Maze procedure is a type of surgery used to correct atrial fibrillation. During this procedure, a series of incisions are made in the right and left atria to confine the electrical impulses to defined pathways.

Why Would I Need a Pacemaker?
Your heart is normally regulated by the heart?s natural pacemaker. This natural pacemaker is called the SA (sino-atrial) node. The SA node automatically increases your heart rate in response to your body?s needs -- for example, during exercise, when a faster heart rate is required. Sometimes, the SA node stops working properly. It may improperly speed up or slow down the rate at which it sends out electrical signals. If the signal rate is too slow, the chambers of the heart do not contract often enough to supply the proper amount of blood to your body.

What Is Heart Block?
Problems may also occur with the electrical pathway between the upper heart and the lower heart. The natural pacemaker signals sent out by the SA node may be delayed in the AV (atrioventricular node) or may fail all together. This condition is called "heart block." Heart block often means that the ventricles pump too slowly even though the SA node may be sending out faster signals in an effort to increase the heart rate.

What Is a Pacemaker System?
Your pacemaker alters your heart rate to help meet your body?s needs. It does this by providing pacing signals that are much like the heart?s normal signals. Depending on your particular situation, your pacemaker may:

  • Replace the function of the heart?s natural pacemaker or SA node.
  • Help maintain a normal timing sequence between the upper and lower heart.
  • Make sure critical lower chambers of the heart always contract at an adequate rate.

What Makes Up a Pacemaker?
A pacemaker is roughly the size of a silver dollar and about as thick as 2 silver dollars together. The pacemaker system is powered by a small battery sealed inside the pulse generator. The battery cannot be recharged. For this reason, the pulse generator must be replaced when the battery?s energy is used up. The pacemaker also includes several electronic circuits. These circuits control the pacemaker?s functions, including the way it monitors your heart?s activity. Replacement of the device usually occurs in 4-8 years.

Pacemaker Types
There are two basic kinds of pacemakers: single-chamber and dual-chamber. A single-chamber pacemaker has one lead to carry signals to and from one chamber of your heart --either the right atrium or the right ventricle. A dual-chamber pacemaker has two leads, with the tip of one lead positioned in the right atrium and the tip of the other lead located in the right ventricle

How Is a Pacemaker Implanted?
The lead(s) are positioned in the right ventricle and also in the right atrium (when needed). A pocket is formed under the skin of the upper chest. The pacemaker is then connected to its leads. Most pacemaker surgery is done under local anesthesia. Additional medicine may be given in an IV to help the patient relax. The procedure typically takes 1 to 1 ? hours.

What Are the Complications of having a Pacemaker?
All surgical procedures contain risks. These should be discussed with a physician.

What Happens After a Pacemaker Is Implanted?
Once the pacemaker is implanted, it is important that the patient be followed by a pacemaker clinic or a commercial group that specializes in pacemaker follow-up. The physician implanting the pacemaker should help the patient arrange appropriate follow-up. Pacemaker follow-up is usually done on a defined schedule. The schedule may vary depending on who is in charge of following or checking the pacemaker. Some physicians will prefer that the patient be seen in the office on a regular basis to have the pacemaker checked. Others will arrange a pacemaker check to be done by telephone, called transtelephonic monitoring, with periodic visits in the office or clinic. In many offices, the pacemaker check will be performed by a nurse or technician that is specially trained in management of pacemakers.

Pacemakers are checked with a special device called a programmer. A portion of the programmer is simply held over the pacemaker and is able to communicate with the pacemaker. It can obtain information about the function of the pacemaker. It can also change certain functions of the pacemaker to whatever the doctor, nurse, or technician feels is most appropriate. A special magnet may also be used during the pacemaker evaluation, and if transtelephonic monitoring is part of the follow-up, a magnet will probably be given to the patient to use during the telephone evaluations.

How is the battery replaced in the pacemaker?
The battery is sealed inside the pacemaker case, or can, which also contains the electronic circuitry. When the battery?s energy is depleted, a new pacemaker must be implanted. The surgery needed to remove the old pacemaker and implant the new one may require only a local anesthetic and is generally a very brief operation. In most cases, your original pacemaker lead(s) will not need to be replaced.

Is there a chance that my pacemaker will fail?
Yes, there is a remote possibility that any electronic device can fail, but technical advances in recent years have made it possible to make pacemakers very reliable.

What happens if my pacemaker does fail?
If your pacemaker should fail to function properly, you may experience the same symptoms that you had before you received the pacemaker. If you ever have these symptoms, contact you doctor as soon as possible.

Can I use my cellular phone?
Yes. In certain cases, a cellular phone could affect your pacemaker?s operation if it is closer than six inches. This interaction is temporary, and moving the phone away from the pacemaker will return it to proper function. To reduce the chance of interaction, maintain a distance of at least six inches between the cellular phone and your pacemaker; hold the cellular phone on the opposite side of your body from your pacemaker; do not carry a cellular phone in a breast pocket or on a belt if that places the phone within 6 inches of your pacemaker.

Will microwave ovens interfere with my pacemaker?
Microwave ovens will not interfere with pacemakers that are manufactured today or in recent years. Patients with pacemakers may use microwaves without concern.

Is there other electronic equipment that will interfere with my pacemaker?
Certain types of welding equipment could interfere with a pacemaker and should be discussed with your physician prior to using. There are other industrial sources of potential interference. If you work in an environment where heavy equipment is used, it is worthwhile discussing it with your physician to be certain there is no concern.

Certain types of hospital equipment may cause interference. MRI or magnetic resonance imaging equipment is capable of interference and is generally not performed in patients with pacemakers. MRI has been done in special circumstances in patients with pacemakers. If an MRI was felt to be critical, this would require discussion between you and the doctor ordering the MRI.

Why is an angiogram done?
Angiography is done to:

  • Evaluate possible problems with blood vessels that affect blood flow, such as a tear that can cause blockage or internal bleeding, aneurysms that indicate a weakness in the blood vessel wall, narrow areas, and blockage caused by blood clots or the buildup of fatty deposits.
  • Detect changes in the blood vessels that lead to injured or damaged organs.
  • Investigate the pattern of blood flow to a tumor. This can help determine the extent of the tumor and guide treatment.

Occasionally, interventional radiology may be used during angiography to treat diseases through blood vessels. For example, a catheter can be used to open a blocked blood vessel, to deliver medication to a tumor, or to stop intestinal bleeding caused by diverticular disease. To stop intestinal bleeding, the catheter is moved into the small artery where the bleeding is occurring, and medication that constricts the artery or causes the blood to clot is injected through the catheter.

How to prepare or an angiogram
Before the angiography procedure, tell your doctor if you:

  • Are or might be pregnant.
  • Are allergic to the iodine dye used in the contrast material or any other substance that contains iodine.
  • Have ever had a serious allergic reaction (anaphylaxis) from any substance (such as the venom from a bee sting or from eating shellfish).
  • Have asthma.
  • Are allergic to any medications.
  • Have any bleeding problems or are taking blood-thinning medication.
  • Have a history of kidney problems or diabetes, especially if you take metformin (Glucophage) to control your diabetes. The contrast material used during angiography can cause kidney damage in people who have poor kidney function. If you have a history of kidney problems, blood tests (creatinine, blood urea nitrogen) may be done before angiography to confirm that your kidneys are functioning properly. For more information, see the medical tests Creatinine and Creatinine Clearance and Blood Urea Nitrogen.

Do not eat or drink for 4 to 8 hours before the test.

If you are not spending the night in the hospital after having this test, you should arrange to have someone take you home. Check with your doctor ahead of time to find out when you will be able to go home.

The test may take several hours, so you may want to go to the bathroom just before it begins.

You may have a routine blood test done before the angiography. You may also be given a sedative to help you relax and to prevent pain about an hour before the test.

You may be asked to sign a consent form before the procedure. Take this opportunity to discuss any final concerns you may have about the need for the test, the risks of the test, or how it will be done.

You will be observed for several hours after the test, so you may want to bring some reading materials or a project (such as knitting) to pass the time during this period.

How is an angiogram done?
Angiography is usually done by a doctor who specializes in evaluating imaging tests (radiologist). The doctor is often assisted by a radiology technologist and a nurse.

You will need to remove jewelry that might interfere with the X-ray picture. You will need to take off all or most of your clothes, depending on which area is being examined (you may be allowed to keep on your underwear if it does not interfere with the test). You will be given a cloth or paper covering to use during the test.

An intravenous (IV) needle may be inserted into the back of your hand or the inside of your elbow. This allows the doctor to give you medication or additional fluids quickly, if needed, during the procedure. A device (called a pulse oximeter) that measures oxygen levels in your blood and monitors your pulse may be clipped to your finger. Electrodes that monitor your heart are usually taped to your arms, chest, or legs.

During the test, you will lie on your back on an X-ray table. You may want to ask for a pad or blanket to make yourself more comfortable before the procedure begins. The area of your body to be studied will be placed in the correct position and may be held in place with a strap, tape, or sandbags. A lead shield or apron may be placed over your genitals and pelvic area to protect them from X-ray exposure.

A round cylinder or rectangular box that produces the X-rays (fluoroscope) will be moved directly above you. The fluoroscope will move up and down during the test.

The contrast material is injected into a blood vessel through a catheter. The place where the catheter will be inserted (in the groin or above the elbow) will be shaved and cleaned. The doctor then injects a small amount of local anesthetic to numb the area and a needle is inserted into the blood vessel. A guide wire will be inserted into the blood vessel through the needle, and the needle is removed. The catheter will be placed over the guide wire and inserted into the blood vessel. Then it is guided through the blood vessels until the catheter tip is in the area to be studied. The catheter location will be checked using the fluoroscope.

When the catheter is in place, the contrast material is injected through it. During the injection you may be asked to take a breath and hold it for several seconds. A rapid series of X-ray pictures will be taken, developed, and reviewed immediately. You need to lie very still to avoid blurring the pictures. Depending on the results, more contrast material may be injected so more X-rays can be taken.

The catheter is kept open by flushing it with a salt solution containing a medication (heparin) that keeps blood from clotting. Your pulse, blood pressure, and breathing rate are usually monitored throughout the test.

Angiography usually takes between 1 and 3 hours, depending on how long it takes to position the catheter and how many X-ray pictures are needed. When the test is over, the catheter is removed and pressure is applied to the needle site for 10 to 15 minutes to stop any bleeding. A bandage is then applied. You will be given medication for pain if you need it.

If the catheter was inserted into your arm, you should not have any blood drawn from that arm or your blood pressure measured in that arm for several days. If the catheter was placed in the groin area, try to keep that leg straight for 12 hours if an artery was used or 8 hours if a vein was used. Your doctor will give you specific instructions following the test. You can apply an ice pack to the puncture site to help relieve pain. Beyond the first day after the test, occasional warm soaks can help relieve pain and speed healing of the puncture site.

How do you feel after an angiogram?
The injection of pain medication may sting briefly. You may feel a brief, sharp pain when the catheter is inserted into the vessel. You may also feel pressure within the artery as the catheter is moved. Let your doctor know if you are uncomfortable. Your discomfort may be relieved by additional injections of pain medication.

When the contrast material is injected, you will probably feel warmth in the area of your body that is being examined. This sensation lasts only a few seconds. Ask your doctor to tell you in advance where and when you will feel the heat. For some people, the sensation of heat is strong and for others it is very mild.

You may also have a brief headache, flushing of the face, or a salty or metallic taste in your mouth. These sensations will also pass quickly. Some people may feel nauseated or may vomit, but this is uncommon.

After the test, you may notice some tenderness and bruising at the site where the catheter was inserted.

Risks of an angiogram?
Although the risk of any major problem caused by angiography is extremely small, there are a number of complications that can occur. In most cases, the complications occur within 2 hours after the test.

  • There is a slight risk of developing an allergic reaction to the iodine contrast material. The reaction can be mild (itching, rash) or severe (difficulty breathing or sudden shock). Death resulting from an allergic reaction is rare. Most reactions can be controlled using medication. Be sure to tell your doctor if you have allergies of any kind (such as hay fever, iodine allergy, asthma, hives, or food allergies).
  • There is a small risk that the catheter may damage an artery or dislodge a piece of clotted blood or fatty deposit from the artery wall. The dislodged object can block blood flow and cause damage to the brain (stroke), arm, leg, or intestine (bowel).
  • Excessive bleeding from the needle site in the artery is rare but possible. In addition, a blood clot can form where the catheter was inserted. This may cause partial blockage of a blood vessel to the arm or leg.
  • Damage to the kidneys is a possible risk that may lead to kidney failure. Contrast material used during the test can cause excessive water loss or direct damage to the kidneys. This is a special concern for people who have kidney problems, diabetes, or dehydration. Special precautions are usually taken during the test to prevent problems for people with these conditions.
  • There is always a slight risk of damage from being exposed to any radiation, including the low levels of X-rays used for this test. However, if this test is really needed, the risk of damage from the X-rays is usually very low compared with the potential benefits of the test.

If you notice weakness in the muscles of your face, vision problems, or slurred speech, or if your leg or arm becomes cool, pale, or numb during or after the procedure, notify your doctor immediately.

What are the test results of an angiogram?
The doctor may be able to discuss some results immediately after the test. Full results should be ready within 2 days.


  • The contrast material flows evenly through the blood vessels.
  • No narrowing, blockage, bulging, or other abnormality of the blood vessels is seen.


  • A narrow spot in an artery may indicate a fatty deposit, clot, or other narrowing that reduces blood flow through the blood vessel.
  • Blood vessels that are not in their normal position may indicate that a tumor or other growth is pushing against them.
  • A bulge in a blood vessel may indicate a weakness in the blood vessel wall (aneurysm).
  • An unusual pattern of blood vessels may indicate the presence of a tumor.
  • Contrast material that leaks out of a blood vessel may indicate a bleeding blood vessel.

What are the affects of an angiogram?

  • Angiography is not usually done for pregnant women because the X-rays could damage the developing fetus.
  • The results of angiography may not be accurate if you cannot remain still or hold your breath during the test.
  • Blockage of the blood vessels through which the catheter is guided may make it difficult to position the catheter in the proper location for injecting the contrast material.

What to think about before you have an angiogram?

  • Magnetic resonance angiography (MRA) and CT angiography are replacing conventional angiography in many situations because these tests are less invasive and easier to perform than conventional angiography. Results obtained from MRA and CT angiography may sometimes be just as accurate as the results obtained from conventional angiography (see the medical tests Magnetic Resonance Angiography and CT Scan of the Body). However, some surgeons may prefer having the results from a conventional angiogram before proceeding with surgery to repair a damaged or abnormal blood vessel.
  • For people with kidney problems, diabetes, or dehydration, steps may be taken to prevent kidney damage. Less contrast material may be used, and additional fluids may be provided before, during, and after the test.
  • In the rare event that excessive bleeding occurs from the puncture in the artery where the catheter is inserted, surgery may be necessary. There is also a substance (called Angio-Seal) that can be used to help plug the artery and stop the bleeding. The substance used to plug the artery is normally absorbed by the body within several months.
  • Digital subtraction angiography (DSA) combines the X-ray techniques of angiography with a high-speed computer to improve the X-ray pictures of blood flow through the arteries. During DSA, two X-ray pictures are taken: one before the contrast material is injected into a blood vessel, and a second one after the contrast material is injected. A computer then subtracts images of bone, tissues, and other interfering structures that appear in the first picture from the second picture. The resulting X-ray picture, displayed on a video monitor, shows only the blood vessels. DSA requires less contrast material than standard angiography, but the technique is more sensitive to movement of the person being tested.