Chest CT Angiogram (Pulmonary and Aortic) - Benefits and Risks

Benefits

  • CT angiography is able to detect blood clots in the lungs, or significant abnormalities in other blood vessels in the chest, including dilation or dissection of a vessel, allowing for potentially corrective therapy to be done.
  • CT angiography may give more precise anatomical detail than magnetic resonance imaging (MRI), particularly in small blood vessels and is not as affected by motion.
  • Many patients can undergo CT angiography instead of a conventional catheter angiography (catheterization) to diagnose blood vessel problems.
  • Compared to catheter angiography which involves placing a catheter (plastic tube), usually at the groin, into your major blood vessels and injecting contrast material, and may require sedation or general anesthesia, CT angiography is faster, non-invasive and has less complications.
  • CT angiography is a lower cost examination compared to catheter angiography.
  • There is also potentially less discomfort because contrast material is injected into an arm vein rather than into a catheter inserted into a large artery or vein.
  • No radiation remains in a patient's body after a CT examination.
  • X-rays used in standard CT exams have no immediate side effects.

Risks

Most patients complete this exam with no adverse events.

  • There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis will generally outweigh the risk.
  • If you have a history of allergy to x-ray contrast material, your doctor may advise you to take special precautionary medication, such as a steroid, for a few hours or the day before CT angiography to lessen the chances of allergic reaction. Another option is to undergo a different exam that does not require iodinated contrast material injection such as MRI.
  • In patients who are at risk for kidney failure and who already have borderline kidney function, administering iodinated contrast material could potentially further damage kidney function. Check with your referring doctor and radiologist to obtain more information regarding this risk.
  • Women should always inform their radiologist or CT technologist if there is any possibility that they are pregnant.
  • The risk of serious allergic reaction to contrast materials that contain iodine is extremely rare, and radiology departments are well-equipped to deal with them.

Watch the CT - What to Expect Video.