Noninvasive evaluation of the heart’s arteries.
Coronary CT Angiography, also known as CT coronary angiography or computed tomography coronary angiography, is a noninvasive imaging test that allows visualization of the coronary arteries.
The coronary arteries are the blood vessels that carry oxygen and nutrients to the heart muscle. Narrowing or blockage of these arteries can restrict blood flow to the heart and increase the risk of angina or a heart attack.
Using detailed images obtained through computed tomography and an iodinated contrast agent, the doctor can examine the anatomy of the coronary arteries and identify atherosclerotic plaques, narrowings, or certain abnormalities in the blood vessels.
At MedicalES, the Coronary CT Angiography is performed at the Phoenix Clinic by a team specializing in cardiovascular imaging. The physicians and medical staff involved have dedicated experience in performing and interpreting this test and work together to carefully evaluate each case. The examination is performed based on a medical recommendation, following a protocol tailored to each patient’s health status and medical history.
What Is a Coronary CT Angiography?
Coronary CT Angiography combines computed tomography with the intravenous administration of an iodinated contrast agent.
The contrast agent reaches the coronary arteries via the bloodstream and allows them to be visualized on CT images. The data obtained are then processed using specialized software, which enables three-dimensional reconstruction and examination of the vessels from multiple angles.
Unlike invasive coronary angiography, Coronary CT Angiography does not require the insertion of a catheter through an artery into the heart. The contrast dye is administered through a peripheral vein, usually in the arm.
Coronary CT Angiography is primarily a diagnostic test. If a stenosis is identified that requires interventional treatment, the doctor may subsequently recommend invasive coronary angiography.
What can a Coronary CT Angiography reveal?
The examination allows for an assessment of the lumen and walls of the coronary arteries.
A Coronary CT Angiography can be used to evaluate:
- the origin and course of the coronary arteries;
- the presence of atheromatous plaques;
- calcified and non-calcified plaques;
- the degree of narrowing of the arteries;
- any coronary blockages;
- congenital anomalies of the coronary arteries;
- the patency of certain coronary bypass grafts;
- in certain cases, the evaluation of coronary stents;
- general anatomy of the heart and the great vessels;
- other visible changes in the region under examination.
The quality of the results may be affected by heart rate, irregular heartbeat, breathing, and the patient’s ability to remain still.
When is a Coronary CT Angiography recommended?
Testing may be recommended based on symptoms, risk factors, and the results of previous tests.
Coronary CT Angiography may be indicated for:
- evaluation of chest pain suspected to be of cardiac origin;
- ruling out coronary artery disease in carefully selected patients;
- investigating inconclusive results obtained from other tests;
- evaluation of patients with a low or moderate probability of coronary artery disease, as determined by the physician;
- identification and characterization of atheromatous plaques;
- assessment of congenital anomalies of the coronary arteries;
- assessment of coronary anatomy prior to certain procedures;
- evaluation of coronary bypasses;
- monitoring certain patients with known cardiovascular disease;
- to determine the cause of symptoms such as chest pain or shortness of breath.
The indication is not determined solely on the basis of symptoms. The doctor will take into account the patient’s age, medical history, cholesterol levels, blood pressure, smoking status, diabetes, family history, and the results of previous cardiac evaluations.
What is the difference between a Coronary CT Angiography and a calcium score?
The coronary calcium score and Coronary CT Angiography are different tests.
Coronary Calcium Score
This is a CT scan that is typically performed without contrast dye. It measures the amount of calcium present in the walls of the coronary arteries and can help assess cardiovascular risk.
However, the calcium score does not accurately reflect the condition of the inside of the arteries and does not fully characterize non-calcified plaques.
Coronary CT Angiography
It is performed using a contrast agent and allows visualization of the coronary arteries, the vascular lumen, and atherosclerotic plaques. It can help identify and assess the severity of coronary stenoses.
The doctor determines which of the two tests is appropriate based on the purpose of the evaluation.
Coronary CT Angiography or Invasive Coronary Angiography?
Coronary CT Angiography is a noninvasive test and is primarily used for diagnostic purposes.
Conventional coronary angiography is an invasive procedure that involves inserting a catheter through an artery in the hand or foot and advancing it to the coronary arteries. A major advantage of invasive coronary angiography is the ability to perform treatment during the same procedure when significant stenosis is identified and there is an indication for angioplasty and stent placement.
The two tests are not interchangeable in all situations. The choice is made by the doctor based on the likelihood of coronary artery disease, symptoms, the urgency of the case, and the need for a possible procedure.
How Do You Prepare for a Coronary CT Angiography?
Proper preparation helps ensure high-quality images and allows the examination to be conducted safely.
When scheduling an appointment, the patient should indicate whether they:
- have kidney problems;
- have diabetes;
- are undergoing treatment with metformin or other medications;
- have known allergies;
- had a reaction to the iodinated contrast agent;
- have asthma;
- have thyroid disorders;
- have very low blood pressure;
- have heart rhythm disorders;
- are pregnant or there is a possibility of pregnancy;
- are breastfeeding;
- are undergoing treatment for erectile dysfunction;
- have other relevant medical conditions or treatments.
Prior to the examination, a test may be required to assess kidney function, typically a serum creatinine test. The validity period of the test results and information regarding other required documents will be provided at the time of scheduling.
Depending on the center’s protocol, the patient may be advised to:
- not consume coffee, tea, energy drinks, or other caffeinated products before the exam;
- avoid smoking on the day of the examination;
- not to eat for a certain period of time before the appointment;
- drink water as directed;
- take their usual medication, unless their doctor recommends otherwise.
The patient should not stop or change their treatment on their own. Any changes to the medication should be made only on a doctor’s recommendation.
It is helpful to bring:
- a medical recommendation;
- the results of the requested tests;
- electrocardiograms and cardiac ultrasounds;
- stress tests or other cardiac evaluations;
- previous CT scans or coronary angiograms;
- discharge papers;
- a list of treatments used;
- documents related to stents or bypasses, if any.
How is the investigation conducted?
Before the scan, the patient is evaluated by the medical team. The team reviews the patient’s documents, medical history, kidney function, allergies, and any contraindications.
Electrodes are placed on the chest to monitor and synchronize the images with the heart’s activity. An IV catheter is inserted into the arm through which the contrast agent is administered.
To obtain clear images, it is important for the heart rate to be regular and, in certain situations, low enough. If necessary and if there are no contraindications, the doctor may administer medication to temporarily lower the heart rate.
In some cases, a medication that temporarily dilates the coronary arteries may also be administered. The patient should inform the medical team about all medications they are taking, especially certain medications for erectile dysfunction, as there may be significant interactions.
During the scan, the patient lies on the scanner table and must remain still. The patient will be asked to hold their breath for a few seconds.
When the contrast agent is administered, you may experience a temporary sensation of warmth in your body, a metallic taste, or the urge to urinate. These sensations usually subside quickly.
The scan itself is brief, but the total time spent at the clinic may be longer due to preparation, heart rate monitoring, the administration of any necessary medications, and post-exam monitoring.
What are the contraindications and limitations?
Coronary CT Angiography may not be indicated or may require special precautions in the following cases:
- pregnancy;
- severe kidney failure;
- a previous severe allergic reaction to iodinated contrast media;
- significant heart rhythm disorders;
- a heart rate that is difficult to control;
- the patient’s inability to hold their breath;
- very extensive coronary calcifications;
- obesity that exceeds the technical limits of the equipment;
- contraindications for the medications required for the preparation.
The presence of these conditions does not always lead to the cancellation of the investigation. The physician evaluates the benefits, risks, and feasibility of using a tailored protocol on a case-by-case basis.
What are the benefits of a Coronary CT Angiography?
Coronary CT Angiography is a noninvasive, rapid, and accurate test that allows for the visualization of the coronary arteries and the identification of any narrowings or atherosclerotic plaques.
The main advantages are that it:
- provides detailed images of the coronary arteries and the structures of the heart;
- can detect coronary artery disease at an early stage, including plaques that do not yet cause symptoms;
- helps assess the degree of narrowing in the arteries;
- is a noninvasive procedure that does not involve inserting a catheter into the heart;
- has a short examination period;
- may help avoid invasive tests when the result is normal;
- provides useful information for determining the course of treatment and monitoring the patient.
The results are interpreted by the specialist and considered in conjunction with the patient’s symptoms, medical history, and other test results.
