• Signs and symptoms of coronary artery disease like chest pain

• High risk factors of coronary heart disease like diabetes , increased blood pressure etc
• To assess the effectiveness of cardiac procedures done to improve the blood circulation to heart.

Preparation of the Patient

• The patient should not smoke before the procedure.
• He should not drink or eat (especially tea, coffee, cocoa or soda which all increases the heart rate).
• He should stop medications taken for heart ailments
• He should be described the details of the procedure.

Rate this Article

Excellent   Good   Average   Bad   Terrible Current Rating

Procedure

• The patient is connected with monitors to record the ECG/EKG, blood pressure and heart rate.
• He is made to walk on a treadmill or pedal a stationary bicycle.
• The speed of the treadmill or the pedaling of the bicycle is increased.
• Just before the end of the exercise which is determined when the heart rate reaches 85% of the maximum accepted rate for that age, the radio active isotope dye Thallium201 is injected into a blood vessel through an already fixed intravenous cannula and it is flushed with normal saline to make sure the dye enters the blood adequately. This is the exercise phase.
• After an interval of 20 minutes which is taken by the dye to get concentrated in the heart, the patient is made to lie down and the images of the heart are taken with a gamma camera.
• He is made to relax for 3-4 hours, again with the instructions of not to consume tea, coffee, cocoa and soda.
• Now the dye is injected for the second time and images taken with a gamma camera. This is the resting phase
• The two set of images are then analyzed

Interpretation

• If the images of both the resting and the stressed heart are normal, it indicates that the heart is getting adequate blood supply.
• If the images of the resting heart are normal, and the stressed heart is abnormal, it indicates that there is block in the blood vessels preventing increased blood supply to the heart during stress.
• If the images of both the resting heart and the stressed heart are abnormal, it indicates that there is a constantly low blood supply.
• If the radioactive isotope is not concentrated in any of the portion of the heart, it indicates that the portion is dead scar tissue which could be due to a previous heart attack.

Safety of the Procedure

• Since only a little quantity of the radioactive isotope is injected, hazards due to radiation are minimal.
• If the patient feels dizzy, breathless, low blood pressure or develops chest pain, the procedure is stopped immediately. A qualified medical professional should be always be by the side of the patient to handle emergencies.

Stress Test in the Sick Patients

Other Scans

Technetiums Scan

Dual Isotope Scan

MUGA Scan

Role of Cardiac nuclear stress tests

Related Articles