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Contrast agent imaging and procedures of blood vessels

Angiographic examinations are contrast agent imaging of blood vessels.

The purpose of contrast agent imaging and procedures involving blood vessels is to examine the vascular system, identify any possible narrowings, and treat them. In addition to imaging, a wide range of procedures are performed in the angiography unit. These procedures may include balloon angioplasty, placement of a stent i.e. metal mesh, thrombolysis i.e. dissolution of a blood clot, or embolization i.e. blocking blood flow. 

Angiography is often performed on patients who arrive from a hospital ward, where nurses carry out the preparations and administer any necessary premedication. 

If you are coming from home for the examination, check the patient instructions you received for specific preparation guidelines. 

If you have a known allergy to iodine-based contrast agents, inform your treating physician or at the latest when you arrive for the examination. 

If you know or suspect that you are pregnant, inform your treating physician or at the latest when you arrive for the examination. 

Angiographic examinations are performed by a radiologist together with radiographers. During the procedure, a catheter is inserted under local anesthesia, usually through the femoral artery, to the area being examined. Iodine-based contrast agent is then injected into a vein, and a series of images is taken using an X-ray device. The contrast agent may cause a sensation of warmth at the injection site. It is excreted from the body through urine. 

Angiographic procedures typically last about 1–3 hours. You will be awake during the procedure, and your condition will be monitored. You can communicate with the doctor and nurses during the examination. 

After the contrast agent imaging, bed rest duration varies from 2 to 12 hours. Post-procedure rest is important to prevent bleeding from the puncture site. 

You will receive aftercare instructions in the radiology department, including advice to avoid strenuous activity for four days. 

The physician who referred you for the examination will inform you of the results and the continuation of treatment. Contact your care unit if you do not have a scheduled follow-up appointment or phone consultation. 

Contrast agents may occasionally cause allergic reactions, although this is rare. Imaging unit staff will always ask about known allergies in advance. All units are prepared to manage allergic reactions with appropriate medication. 

Updated 6.11.2025