A calcium-scoring CT scan, also known as coronary artery calcium (CAC) scan, detects calcium deposits in the coronary arteries. This test assesses the risk of coronary artery disease (CAD), which can lead to cardiovascular events such as angina, heart failure, and sudden cardiac arrest.
A calcium-scoring CT scan is generally recommended for individuals at intermediate risk of CAD without symptoms. It includes:
The test is not typically recommended for individuals under 40; early coronary artery calcium accumulation is rare. Those who have experienced a heart attack, stroke, or another serious cardiovascular event are at high risk and require extensive management. Pregnant women and others who need to avoid radiation should not undergo a CAC test. For people with a recent CAC test, it can be repeated in three to five years if the initial score was zero and management is still being determined.
The primary purpose of a calcium-scoring CT scan is to identify and quantify calcified plaque in the coronary arteries. Calcified plaque indicates atherosclerosis, a condition characterized by fatty deposits within the arterial walls that can lead to CAD.
Patients are typically asked to avoid smoking for several hours before the procedure. They lie supine on a table that slides into the CT scanner, with electrodes attached to their chest to monitor heart activity. The scanner takes multiple heart images in seconds, making the procedure quick, non-invasive, and painless.
Calcium-scoring CT scan results are expressed as a calcium score, quantifying the amount of calcium in the coronary arteries:
A score of 0 signifies no identifiable plaque and suggests a low risk of CAD, prompting a review of prevention guidelines. Scores between 1-10 indicate minimal plaque, also corresponding to a low risk, with similar preventive recommendations. A score of 11-100 denotes mild plaque presence, translating to a low to moderate risk of clinical CAD, necessitating risk factor modifications. Scores ranging from 101 to 400 reveal moderate plaque accumulation associated with a moderate risk of CAD, requiring risk factor modifications and clinical follow-up. Finally, a score over 400 indicates extensive plaque, suggesting a high risk of clinical CAD, which calls for aggressive risk factor modification, clinical follow-up, and potentially further testing.
The calcium-scoring CT scan offers several benefits. It allows early detection of CAD before symptoms appear, provides risk stratification to guide further testing and treatment, and is non-invasive, unlike procedures requiring catheterization.
However, the scan has limitations. It involves minimal radiation exposure and may not be suitable for individuals with very low or very high risk of CAD. Additionally, it only detects calcified plaques and does not measure soft or non-calcified plaques, which can also contribute to CAD.
Clinically, calcium-scoring CT scans are used primarily for asymptomatic individuals with intermediate risk of CAD. The results help decide on preventive measures such as lifestyle modifications, medications, or the need for further diagnostic tests.
In conclusion, a calcium-scoring CT scan is a valuable diagnostic test that aids in the early detection and risk assessment of CAD. It helps guide effective preventive and therapeutic strategies to reduce the risk of cardiovascular events.
The calcium-scoring computer tomography or calcium-scoring CT scan detects calcium deposits within the plaque in the coronary arteries.
It detects early coronary calcification and confirms suspected coronary artery disease or CAD, primarily in individuals at intermediate risk, such as those with hypercholesterolemia and hypertension.
During the procedure, position the patient supine on the CT table and attach the ECG electrode to the chest to monitor the heart rate.
Instruct the patient to hold their breath briefly during the scan to ensure clear images. Then, slide the table into the CT scanner, which rotates around the patient's body to take multiple images.
Lastly, results are expressed as a calcium score, quantifying the calcium in the coronary arteries:
A score of 0 signifies no identifiable plaque. Scores 1 to 10 indicate minimal plaque, while 11 to 100 denote mild plaque and low CAD risk.
Scores from 101 to 400 reveal moderate plaque accumulation associated with a moderate CAD risk. A score over 400 indicates extensive plaque, suggesting a high CAD risk.
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