CT Angiography

Your appointment is for 10 a.m. and you've looked inside your refrigerator about five times since you woke up this morning. It's the day you're scheduled for a CT angiography and the only thing you can remember about your procedure is that you can not have any solid food beforehand. The idea of not eating has pervaded your thoughts as if you were told you could never eat again. And the funny thing is you're probably not even a breakfast person. Would you like to get your mind off of not eating? Now would be a good time to catch up on the material your doctor gave you to read about CT angiography. Oh, so you've misplaced your reading material. No need to worry. I have you all covered. The information here will provide you with a review to help you understand the procedure and what you need to do to prepare yourself.

The CT angiography (CTA) procedure gets into the "business" of your health without the hassle of some other medical procedures like catheter angiography (CA). The use of CA is not as patient-friendly as CTA because a sizable catheter is used and contrast dye is injected into a larger artery or vein. CTA is minimally invasive and helps your doctor get a clearer understanding of your disease. The purpose of CTA is to provide 3-dimensional images of your blood vessels. This is achieved by injecting an iodine-based contrast medium into a peripheral vein. Once that has been given enough time to move through your system cross-sectional X-rays are taken of the questionable area or organ.

So, why have you been selected to get a CTA. Well some of the indications for this procedure include:

Identifying aneurysms
Assessing atherosclerosis in the lower extremities
Detecting renal artery disease
Visualizing vein thrombosis
Diagnosing CAD in women with atypical chest pains and multiple risks

Aside from the all too familiar "no solid or liquid" intake policy, there are other things you should be aware of to help you prepare for your CTA procedure. For starters, wear loose fitting clothes. You may be given a gown to wear which will make dressing and undressing all the more easier. You will be asked to remove all metal objects such as hairpins, glasses, jewelry, hearing aids and dentures. Don't forget to report any medical issues, recent illness or past history of disease such as asthma, kidney problems or diabetes to your physician. For breastfeeding mothers, it is highly advised that breast milk be pumped and stored for babies. Mothers should discuss the appropriate time to resume breastfeeding with their doctors.

Now, what should you expect when you're actually in the scanning room? Surprisingly, the procedure including prep time takes about an hour or less. The scanning portion itself only lasts about 10-20 seconds. The CTA scanner is a large circular machine that has a hole in the center. While undergoing this procedure you will be lying down on a flat movable table and are required to remain still during the process. The technician or nurse will inject the iodine-based contrast medium via an IV line through your hand or arm. After you've endured the prick of the needle you may experience a warm sensation as the fluid is injected. Some people have also noted a metallic taste lasting for a few minutes. When you are ready to start, your table will begin to slide through the machine as the circular part rotates taking multiple X-ray images of the blood vessels in question. The technician may ask that you hold your breath intermittently for a few seconds each time. Once the procedure is completed a radiologist will review the images and write up any notable problems such as occlusions, stenosis or fluid leaking into the tissues.

The procedure is quick, noninvasive and safe. However, some patients may experience an allergic reaction to the iodine dye. If you know you've experienced an allergic reaction to iodine it is important to inform your physician. Drugs such as antihistamine and cortisone will be prescribed to you the night before to prevent this potential risk.

The use of certain drugs like metformin used in diabetics must be temporarily discontinued because it affects your kidney function. This is critical because impaired kidneys will prolong the excretion of the dye from your system. Doctors usually perform a kidney test to assess functionality in patients that had to stop taking metformin before this procedure. This is done to assure that your kidney is working well before resuming the drug post-CT angiography. Under normal conditions, 95% of the I.V. contrast medium is excreted within 24 hours.

So, now your ready to get your CTA and you haven't even thought about snacking (okay, maybe you have). But, within an hour you would have taken an important step toward diagnosing your medical condition. This will provide information that your physician can use to map out a treatment plan and get you closer to improving your health. CT angiography is a safe procedure that gets to the bottom line with minimal invasion.

Sources: Lora K. Ott, RN, MSN. "Assessing blood flow with CT angiography" Nursing 2008 38.1 (2008): 36-41, http://www.radiologyinfo.org/en/info.cfm?pg=angioct&bhcp=1, http://www.healthnewsdigest.com/news/Women_s_Health_260/Heart_Disease_in_Women_New_Insights_and_Cutting_Edge_Technologies.shtml