Nuclear Stress Testing


The Nuclear Cardiology Stress Test


How should I prepare for a Nuclear Stress Test?


  • Wear comfortable clothing and walking shoes (rubber-soled are best).
  • Do not eat for a minimum of 4 hours before the test. If your appointment is in the morning, do not eat after midnight the night before your test.
  • Drinking water is allowed before the test.
  • If you are diabetic, juice is allowed in the morning with insulin (1/2 dose).
  • Do not drink caffeine (coffee or tea) the day of the test.
  • If your doctor ordered a nuclear stress test involving the injection of a radioisotope, please let us know if you are pregnant or breast-feeding.
  • Because of the high cost of the radioisotope used in the test, please call 24 hours before your appointment if you need to cancel or reschedule.
  • Stop taking all medications, including beta-blockers, calcium channel blockers, nitrates and dijoxin 24 hours prior to your test, unless directed otherwise by your doctor. If you have any questions regarding the medications you are taking, call (915) 532-4542.
  • You should plan on being at the Nuclear Studies Department for a minimum of 3 to 4 hours.


  • Our clinical team will connect you to three monitors:


  • Electrocardiogram or EKG: Attached to several sticky electrode patches placed onto your chest. Provides a picture on graph paper of the electrical impulses traveling through your heart.
  • Oximeter monitor: Attached to a small clip on your finger. Checks the oxygen level of your blood.
  • Blood pressure monitor: Connected to a blood pressure cuff on your arm. Checks your blood pressure intermittently throughout the study.

  • These monitors allow the doctor to check your heart rhythm and the body's responses to arrhythmias.

    How should I prepare for a Nuclear Stress Test?


    The purpose of your test is to determine if and/or where you have coronary artery disease and to find, if any, blockages in the vessels of your heart muscle.  We do this by taking two pictures of your heart.  The first picture, your resting scan, depicts the blood flow to your heart muscle when you are at a relaxed state.  The second picture, your stress scan, depicts the blood flow to your heart muscle when your heart is working hard.  By comparing these images to each other, our cardiologists can determine if you have coronary artery disease.


    When you arrive for your appointment, the first step is to identify you as the patient and get all of the necessary consent forms signed.  Then we will be placing an IV in a vein in your hand or arm.  You will then receive your first dose of the radiation called Sestamibi.  Sestamibi is a radiotracer that follows your blood flow and localizes in your heart muscle.  There are no symptoms or side effects from this injection.  We will let this tracer circulate for a period of time and then take your first set of pictures, your resting scan.  This picture will take about 15 minutes.  After your resting images, you will then be set up for the stress portion of the exam.  EKG leads will be placed on your chest.  You will then walk on the treadmill until your heart rate elevates to a sufficient level.  At your peak exercise, another dose of the Sestamibi will be administered through your IV.  Your stress images will then be taken a period of time after completion of the treadmill.  These again are approximately 15 minutes. 

    Our clinical team will connect you to three monitors:


  • Electrocardiogram or EKG: Attached to several sticky electrode patches placed onto your chest. Provides a picture on graph paper of the electrical impulses traveling through your heart.
  • Oximeter monitor: Attached to a small clip on your finger. Checks the oxygen level of your blood.
  • Blood pressure monitor: Connected to a blood pressure cuff on your arm. Checks your blood pressure intermittently throughout the study.

  • These monitors allow the doctor to check your heart rhythm and the body's responses to arrhythmias.


    How should I prepare for a Nuclear Stress Test?


    If you are scheduled for a Lexiscan exam, you will not be walking on the treadmill, you will be given a drug, Lexiscan, to stress your heart instead of exercise.  Lexiscan does have some side effects/symptoms that the technologist will go over with you before beginning your exam.  The Lexiscan will be injected in your IV over 30 seconds and the Sestamibi will be injected as well.  Your stress images will be taken no earlier than 1 hour after the injection of Lexiscan.