A dye test or cardiac catheterization is a test to examine the working of the heart muscles, its valves and arteries. It is called a dye test because it uses a special kind of dye, which is radio-opaque and X-ray imaging techniques to examine the heart and blood vessels inside the patient's body.


How Long Does It Take To Do A Dye Test or Cardiac Catheterization?


How Long Does It Take To Do A Dye Test or Cardiac Catheterization?

The dye test or cardiac catheterization takes about 30 minutes to an hour to be done on an average. It must be remembered that various factors affect the time duration of a dye test. If other tests and are prescribed along with the dye test, the time duration may vary.


The patient is kept awake throughout the dye test or cardiac catheterization. A mild sedative is given to the patient, which helps him to relax. This is done before the test. After this, the doctor numbs the groin area or the arm of the patient with the help of local anaesthetic. This is done because an incision has to be made to insert a catheter inside. A catheter is nothing but a small flexible tube. The tube is inserted and guided to the blood vessel or artery to be examined. A special type of dye is injected into the catheter. This is the iodine dye which flows up to the blood vessel to be examined through the catheter. As the dye is radio-opaque, it becomes clearly visible under X-ray. Hence a series of X-ray imaging techniques are used as the iodine dye flows through the blood vessels. In this way, any kind of blockage in coronary blood vessels can be detected. The dye test also shows if the working of the heart is proper or not. Once ample X-ray images are taken, the catheter is removed and the incision so made is closed. The dye test is a one day process, but patients may have to stay overnight for observation purposes.

How To Get Ready For A Dye Test or Cardiac Catheterization?

After the doctor asks the patient to undergo a dye test, a specific date is given for the test to be performed. The nurse will measure the height and weight of the patient. These measurements are important because they help the doctor decide the amount of dye that has to be used for the test. Prior the dye test or cardiac catheterization, an electrocardiogram (EKG) may be done to check the impulses produced by the heart of the patient. Sometimes, a blood test is also done along with EKG. Before the beginning of the test, the doctor will explain the procedure of the test in details to the patient. Patient has to sign a consent letter following the explanation. The test starts once all the proceedings are done.

How Long Does The Patient Have To Lie Down After The Dye Test or Cardiac Catheterization?

Since the dye test or cardiac catheterization is a minimally invasive procedure, proper time is to be given for healing the incision. For proper healing and prevention of bleeding from the punctured site, the patient will have to be on complete bed rest for up to six hours. During this time-

  • The patient has to lie down flat on his back.
  • Although the patient can turn his head from side to side, he should not lift the head from the pillow.
  • The patient should not put his elbows above the shoulder or arms behind his head.
  • Care must be taken so that the patient does not cross or bend his legs.

The patient has to avoid stretching activities, such as reaching for things on the bedside table.

Pramod Kerkar

Written, Edited or Reviewed By:


Pain Assist Inc.

Last Modified On: August 1, 2019

This article does not provide medical advice. See disclaimer


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