A cardiac CT is a non – invasive and painless imaging test that uses x – rays to capture images of the heart. It helps to diagnose coronary artery disease and evaluate cardiac function. The CT scan can also assess scarring of the heart muscle, plaque buildup in the arteries, and fluid accumulation in the pericardial sac.
How is Cardiac CT Scan performed?
The CT scanner is a large tunnel-like machine with a sliding table attached to it. The patient is asked to lie down on this table, and electrodes will be attached to his chest to monitor his electrocardiogram (ECG). This ECG is connected to the computer that is attached to the scanner. It helps to monitor the heart rate during the scan. A contrast dye is then injected intravenously into the arm of the patient if needed. It is done to highlight the heart and the blood vessels to get a clearer picture. Once the dye is injected, the table will slide into the scanner.
Inside the scanner, the patient can hear a whirring or buzzing sound while the pictures are taken. Throughout the test, the patient can communicate to the technician via a two–way intercom. The technician may ask the patient to hold his breath for a few seconds to capture good quality images. Generally, the contrast media is injected at a high flow rate (4 – 5 mL/sec) for a cardiac CT scan compared to other CT scans. Apart from this, the patient is also administered with a beta-blocker and sublingual nitrate before the test. These medications are given to lower the heart rate, avoid arrhythmia, and dilate the coronary arteries. This scan is not recommended for pregnant, breastfeeding patients or anyone diagnosed with acute myocardial infarction.
Are there any risks involved in it? :
Due to exposure to a small dose of x – rays, cardiac CT has a slight risk of causing cancer, especially in patients below 40 years of age. The minor complication associated with cardiac CT scan is allergic reactions to the contrast dye.
What are preparations required from the patient?
If contrast dye is to be used, then the patient must not eat for 4 to 6 hours or have caffeinated drinks for 12 hours before the test. Otherwise, he must refrain from eating for 2 hours before the test. Patients with kidney failure and those with metallic objects in the chest (pacemaker, surgical clips) should notify the doctor beforehand.
How long does it take?
The cardiac CT scanning takes about 10 to 15 minutes.
Who performs it?
A radiologist or radiology technologist generally does the cardiac CT scanning.
How much does it cost?
The average cost of a cardiac CT scan lies around Rs. 6K to 12K.
When can I go home after the procedure?
The patient can usually go home and resume his normal activities immediately after the procedure.