General Information |
Scheduling, Insurance and Preparation |
What to Expect
What Coronary CT Angiography Is
CT angiography is an imaging exam that uses x-rays to examine the blood vessels in various parts of the body. A scanner is used to take images which are assembled into three-dimensional views of the blood vessels using state-of-the-art computer software. When used to view the arteries of the heart, this exam is referred to as coronary CTA (or cardiac CTA).
Catheter angiography has been used to examine coronary arteries for years. With catheter angiography, a very thin, long tube is threaded through the groin arteries to the heart. Coronary CTA is a much less invasive procedure.
A negative result from a coronary CTA is a strong indicator that the patient does not have coronary artery disease. Because the test is non-invasive, coronary CTA will likely become the first line diagnostic test to evaluate for the presence or absence of coronary artery disease. In patients with acute cardiac symptoms or angina, however, catheter angiography is still preferred because intervention, such as stenting a narrowed artery, can be performed at the same time.
Coronary CTA may be helpful in patients with unclear causes of chest pain, which is a common patient complaint in doctors' offices and emergency rooms. There are many causes of chest pain and they can be difficult to tell apart. CT angiography may help to rule out the most dangerous causes of chest pain, such as blockage or abnormality of a coronary artery, a pulmonary embolism, or an aortic aneurysm or dissection. In addition, sometimes stress test results are uncertain. In these cases, CT angiography can evaluate the coronary arteries and spare the patient a surgical angiogram.
Following are some additional circumstances under which coronary CTA may be used:
- Detection of sub-clinical heart disease as the basis for primary prevention
- Pre-surgical assessment of coronary arteries
- Evaluation of coronary artery abnormalities
- To check the openness of a stent or bypass graft
Coronary CTA does have limitations. It is not able to image people with irregular heart rhythms. Very obese patients or those with heavily calcified arteries may also not benefit from this exam.
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Benefits of Coronary CTA
Following are some of the benefits of having a coronary CTA over other exams for evaluating a person’s risk of heart attack:
- Coronary CTA is able to detect small amounts of plaque that are missed by other exams. Consequently, it can detect very early disease before a patient has symptoms.
- Coronary CTA allows the radiologist to evaluate other organs near the heart and possibly find other abnormalities, such as lung disease or enlarged lymph nodes. More than one in ten scans will have such findings.
- Coronary CTA allows the radiologist to view the blood vessel walls. With catheter angiography, only the lumen (the opening where the blood flows, like the center of a hose) can be examined. The lumen can often look normal when the blood vessel has actually expanded to compensate for plaque buildup.
Risks Involved in Coronary CTA
Following are some of the risks associated with Coronary CTA:
- Risk of radiation exposure; however, it is well below the level that generally causes adverse affects.
- Risk of allergic reaction to the contrast material used during the procedure.
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Scheduling, Insurance and Preparation
The exam is performed at the following Radiology Imaging Associates partner hospitals in the Denver, Colorado area:
- Medical Center of Aurora
- Porter Adventist Hospital (low radiation option available)
- Sky Ridge Medical Center
- Swedish Medical Center
To schedule a consultation to discuss coronary CT angiography, please contact the hospital of your choice:
|Medical Center of Aurora
|Porter Adventist Hospital
|Sky Ridge Medical Center
|Swedish Medical Center
Coronary CTA is covered by many insurance plans. Check with your insurance carrier to be sure. Please bring your insurance card with you to your exam.
Conditions to Let Us Know About
In advance of your exam, let your nurse or technologist know if any of the following circumstances apply to you:
- Previous reaction to iodine
- Any allergies, particularly to iodine
- Any medications you are currently taking
- Emphysema or chronic obstructive pulmonary disease (COPD)
Following are the general preparation guidelines for coronary CTA. You may receive additional or differing guidelines based on your specific situation. Please contact the hospital where the exam will be performed if you have any questions.
- Do not eat after midnight prior to the day of your exam
- Do not take erectile dysfunction medications (such as Viagra or Cialis)
for 24 hours prior to your scan
- No caffeine within 12 hours of the exam
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What to Expect
Before the Exam
Before your cardiac CTA, you will fill out paperwork and consent forms so the radiologist will know your medical history.
During the Exam
Here is generally what will happen during a coronary ct angiography:
- You will remove all metal and metallic objects, such as eyeglasses, belts, hair accessories and jewelry. You will also change into a gown.
- A technologist will answer your questions then start an intravenous (IV) line in your arm.
- The technologist will measure your heart rate and blood pressure. If your heart rate is over 55 beats per minute, you will be given a drug to slow it down. A slower heart rate allows for better images. Generally, the drug given is a beta blocker called Lopressor (metoprolol) unless you have asthma or emphysema.
- The technologist will place ECG leads on your chest. This enables the CT scanner to register your heart rhythm and process the image data accurately.
- You will be given contrast through the IV to make the arteries more visible.
- Right before the scan, you will receive a nitroglycerin spray under the tongue. This ensures the coronary arteries are dilated, and don't appear falsely narrowed.
- Three scans will be performed: a calcium score CT, a timing run, and the CT angiogram. You will be asked to hold your breath for 10-15 seconds while each set of images are taken. The timing run tells us how long it takes for the contrast to get from the IV in the arm to the coronary arteries. This also helps to ensure the images are optimal. It is extremely important not to move any part of your body during the scan to avoid blurring the images.
- The IV will be removed after the exam is completed.
- You will change back into your clothes.
The technologist will not stay in the room during the scan, but you can speak with him or her throughout the exam by intercom.
After the Exam
After the coronary CTA, you should drink a lot of water for the next 12 hours to help flush the contrast out of your system.
Some patients get a headache after the scan. This is normal and should not be cause for concern. Rarely, patients will develop a skin rash over the next few days as a reaction to the contrast.
A board-certified radiologist experienced in the interpretation of coronary CTA will analyze the data and results from your exam. The results will be reported to your physician. Your physician will pass the results onto you.
During the exam, our radiologists and technologists will be happy to answer questions about the exam itself; however, they will not immediately provide you with the results of your exam.
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