Noninvasive Stress Testing

Stress Echo Testing

Stress test, also called treadmill test is used to determine the functioning of heart and ability to withstand the stress during exercise or physical stress. It usually involves walking on a treadmill, while your electrocardiogram, heart rate, and blood pressure are monitored.

Your physician may recommend an exercise stress test to

• Evaluate coronary artery disease
• Diagnose the causes for chest pain
• Identify abnormal heart rhythms
• Identify if you had an heart attack
• Assess other problems, such as heart valve diseases
• Assess if you had a heart procedure in the past such as angioplasty or heart bypass surgery

Procedure

Electrodes using conductive patches will be placed on the specific areas of the chest to record your heart function.  Before you start exercising, your heart rate and blood pressure are measured at rest. The blood pressure is measured throughout the test. You will begin walking on a treadmill. Gradually the intensity of the exercise is increased, by increasing the speed and incline of the treadmill. The test is stopped after reaching a target heart rate. During this time, your heart rate, electrocardiogram (ECG, and blood pressure are monitored.

Some patients may rarely experience chest pain, dizziness, shortness of breath and severe fatigue during the test.

You may be instructed not to eat, smoke or drink alcohol several hours before the test. You may be asked to wear comfortable clothes during the test. Do not discontinue any medications without consulting your doctor. Certain medications that may interfere with stress test are often avoided.

Abnormal test results may be due to coronary heart disease, arrhythmias, lack of physical fitness, or stress on the heart increased by exercise.

Myocardial Perfusion Imaging

Preparation

• No caffeine for 24 hours prior to the exam (including coffee, tea, “decaf” coffee/tea, chocolate, most sodas, all energy drinks, and some pain relievers).  Please read the labels.
  
  
• No food for four hours. Plain water is permitted and is a good idea, especially if you are hard to draw blood from.
  
  
• No powders or lotions on the chest, and no perfume or cologne please.
  
  
• Please call at least 48 hours in advance if you need to cancel your test. The drugs for your scan are expensive, ordered in advance, and expire within a few hours of your scheduled exam time.
  
  
• You should not undergo this test if you have taken theophylline, dipyridamole, Persantine, Aggrenox, Tegretol, carbamazepine, Viagra, Levitra, or Cialis in the preceding 48 hours.

If you are scheduled for treadmill exercise and are taking a beta blocker, such as metoprolol, Toprol, atenolol, Tenormin, Tenoretic, propranolol, Inderal, Bystolic, carvedilol, Coreg, labetalol, nadolol, bisoprolol or Ziac, and do not have atrial fibrillation, please ask your doctor if you should hold your beta blocker for 24-48 hours prior to your scan.  Please take all of your other medications as prescribed unless you are instructed otherwise by your doctor or are diabetic.  If you are diabetic and your appointment is before 11:30am, hold oral diabetic medication and, if approved by your doctor, take half of your usual insulin dose.  If your appointment is after 11:30am, you may eat 4 hours before your study and take your usual diabetic medications.

Please wear comfortable clothes and shoes for the treadmill.  It is helpful to wear a two-piece outfit (i.e. shirt and pants), as we will be attaching EKG electrodes to monitor your heart.  The procedure is easy, but takes about 3 hours.  At least 40 minutes of this time is spent waiting for the imaging compound to circulate in the body so you may want to bring something to read.  You will need to be able to get up onto an imaging table and lie flat on your back for 16-28 minutes.  We will make you as comfortable as possible with pillows to support your head, back and legs.

The test comes in two parts.  For the first part, you will have an IV installed in your arm or hand.  We will inject the imaging agent through this IV.  There are no side effects from the imaging agent, though some people experience a slight metallic taste in their mouth.

We do not use any x-ray contrast dyes.

Our imaging agents have a small amount of radioactivity that can be seen by a sensitive camera.  Pictures of your heart will be taken by the camera while you lie on your back on the imaging table.

For the second part of the test, we will either have you walk on a treadmill to get your heart rate up, or we will give you a drug instead.

If you are able to walk on a treadmill, we need to get your heart rate up to a level that depends on your age.  The older you are, the less work you need to do on the treadmill.  When your heart rate comes up, we will inject the imaging agent through the IV and have you walk for two more minutes.  After you are done on the treadmill, we will take a second set of images.

If you are unable to get your heart rate up on a treadmill, we will substitute a drug; either adenosine, regadenoson or dobutamine for the treadmill.  This drug is given through the IV while you either sit in a recliner or walk slowly on the treadmill.  This drug will try to relax your coronary arteries.  We will inject the imaging agent while this drug has its effect on your circulation.  The drug’s effect is short in duration, but we do have reversing agents available if needed.  We will then take a second set of images of your heart, but we need to wait 45 minutes before starting.  During this time we would like you to have a small meal, so please bring something with you to eat.  You may have caffeine at that time.

Frequently asked questions:

Is the radioactivity hazardous to me or my family?

No.  You will be given a diagnostic dose of a medically approved agent.  The radiation exposure is similar to that of an abdominal CT series, and no precautions are needed for your children or pets.  However, you should not undergo this test if you are pregnant.

Will I glow in the dark?

No.  However, for a period of time, if you cross the border, go through airport security, or board a ferry, they will notice.  Most security personnel are very familiar with nuclear medicine testing, but you may want to bring this booklet with you to show them.

How long do I have to walk on the treadmill?

It depends on your age; the older you are, the shorter the time.  We are looking to reach a particular target heart rate (based on your age), rather than a distance.

How long do I have to lie on my back?

We will take two sets of pictures of the blood flow to your heart, and each one takes 20-30 minutes.  Pillows will be placed under your knees, neck, and head to make you as comfortable as possible.

I am claustrophobic. Am I going to be enclosed in a tunnel?

No.  The camera rotates around your chest at a distance of about six inches.  Your head is outside of the camera area, and you are able to turn your head and look away.  Unlike an MRI, this camera is quiet.  Most patients who are claustrophobic do fine with this test.

Can my spouse or a relative come with me?

Your spouse, relative, or friend may wait for you in our waiting room.  Because of HIPAA privacy laws, they cannot come with you into the nuclear lab unless they are an interpreter or you have special needs, as there are other patients in the lab whose privacy needs must be respected.

May I use my cell phone in the lab?

No. Cell phones must be turned off.

Can I listen to my iPOD® or CD player?

Yes! Please bring your headphones.

Do I need someone to drive me home?

No.  There will be no lingering effects that will prevent you from your normal activities.

When do I get the results?

You should allow about four working days for a written report to be received by your health care provider.  You should make a follow-up appointment with the provider who referred you.  It is very helpful if you bring the names and addresses of all providers who should receive a copy of your report.

Marko Yakovlevitch, MD, FACP, FACC
Thomas J. Sawyer, MD
Chetan Pungoti, MD

Please note: Above content has been prepared to help you understand the test you are about to undergo. In order to be broadly understandable, the concepts have been simplified and generalized. Please consult your provider for specific and authoritative information.