CT Coronary Calcium Score — Dictation, Appropriateness, and Dose for Residents

1. The 5-Minute Read That Changes Patient Management

You’re on the cardiac rotation, and an outpatient CT Coronary Calcium Score pops up on your list. The indication is “borderline ASCVD risk, statin decision.” It’s a fast scan, no contrast, looks simple. But the cardiologist is waiting on this report to decide whether to start a 50-year-old patient on a lifelong medication. Your attending expects more than just a number; they want the total Agatston score, the per-vessel distribution, the age/sex percentile, and a definitive comment on the incidental lung findings. Getting this right isn’t just about the score; it’s about providing clear, actionable risk stratification. When you’re just starting out, having a solid framework for these common but high-impact studies is key. For more guides like this, check out the residents and fellows resource hub.

2. What a CT Coronary Calcium Score Covers and What Attendings Look For

A CT Coronary Calcium Score is a non-contrast, ECG-gated study designed for one primary purpose: to quantify the burden of calcified atherosclerotic plaque in the coronary arteries. It’s a powerful tool for risk stratification in asymptomatic patients with borderline or intermediate risk for Atherosclerotic Cardiovascular Disease (ASCVD). It directly answers the question of whether subclinical coronary artery disease is present, helping to refine risk estimates beyond traditional calculators.

Common indications you’ll see include:

• Asymptomatic patients with borderline (5-7.5%) or intermediate (7.5-20%) 10-year ASCVD risk to guide statin therapy decisions.
• Patients with a strong family history of premature Coronary Artery Disease (CAD).
• Asymptomatic diabetic patients over 40 without a prior CAD evaluation.

Your attending will expect a report that clearly states:

• The total Agatston score.
• A breakdown of the score by major vessel (LM, LAD, LCx, RCA).
• The patient’s risk percentile based on age and sex (if available from the software).
• A conclusive statement on incidental findings, especially pulmonary nodules, which should be managed according to Lung-RADS criteria.

3. Radiology Report Template for CT Coronary Calcium Score (Agatston)

This template provides a reliable starting point for a clean, comprehensive report. You can adapt it for your institution’s macros in PowerScribe or other dictation systems.

Technique

Non-contrast, prospectively ECG-gated cardiac CT was performed. Axial images were acquired and reconstructed. Analysis was performed on a dedicated workstation to calculate the Agatston coronary artery calcium score.

Findings

Coronary Artery Calcium Score:
Total Agatston Score: [Score]
This corresponds to the [e.g., 78th] percentile for a [age]-year-old [male/female], indicating [mild/moderate/severe] plaque burden for age.

Distribution:
Left Main Coronary Artery: [Score]
Left Anterior Descending Artery: [Score]
Left Circumflex Artery: [Score]
Right Coronary Artery: [Score]
Other (e.g., Ramus Intermedius): [Score]

Other Cardiac and Extracardiac Findings:
Lungs: The visualized lung bases are clear. /or/ [Describe any pulmonary nodules, including size, location, and Lung-RADS category and recommendation].
Mediastinum: No mediastinal or hilar lymphadenopathy.
Aorta: The thoracic aorta is normal in caliber.
Pericardium: No pericardial effusion.
Bones: No acute osseous abnormality.

Impression

1. Total Agatston coronary artery calcium score of [Score], which is in the [percentile]th percentile for age and sex. This represents [e.g., moderate] calcified plaque burden.
2. [If applicable] Incidental [size] mm pulmonary nodule in the [location], categorized as Lung-RADS [category]. Recommend [follow-up per Lung-RADS guidelines].

4. Free Template Sources from the Radiology Community

Building a personal template library is a rite of passage in residency. Beyond your own macros, two great free repositories exist that are curated by radiologists. They are excellent resources for finding templates for studies you may not see every day.

• RadReport.org: Maintained by the Radiological Society of North America (RSNA), this is a comprehensive library of peer-reviewed templates covering nearly every modality and subspecialty. (https://radreport.org/)
• Radiology Templates (AU): A fantastic, user-friendly site maintained by Australian radiologists with a clean interface and practical, well-structured templates. (https://www.radiologytemplates.com.au/home-page/)

5. The Next-Level Move: From Free-Form Dictation to Structured Report

The challenge with templates is that positive findings often break the structure. You find an unexpected lung nodule or aortic calcification, and suddenly you’re free-dictating a paragraph that you then have to manually slot into the right place in the impression. This is where AI-assisted reporting tools can streamline your workflow. Instead of meticulously navigating a template, you can dictate your positive findings in free form. GigHz Precision AI is designed to take that free-form dictation and automatically generate a clean, structured report. It uses pre-loaded templates from the American College of Radiology (ACR) and Society of Interventional Radiology (SIR), ensuring your output is standardized and includes the key elements your attendings are looking for, without the manual copy-and-paste.

6. When Should You Order a CT Coronary Calcium Score? ACR Appropriateness Criteria

The decision to order a calcium score is guided by well-defined risk stratification principles, formalized in the ACR Appropriateness Criteria. The primary use case is for asymptomatic patients where the results will directly influence management, particularly the initiation of statin therapy.

According to the ACR topic on Asymptomatic Patient at Risk for Coronary Artery Disease, a CT Coronary Calcium Score is Usually Appropriate for initial imaging in asymptomatic patients with low, intermediate, or high risk for coronary artery disease. The key is that the patient is asymptomatic and the result will help guide therapy. For patients with a low 10-year ASCVD risk (<5%), the test can help reclassify those with other risk-enhancing factors (like a strong family history). For the most common group—those with borderline (5-7.5%) or intermediate (7.5-20%) risk—a score of zero can provide confidence in deferring statin therapy, while a high score can motivate more aggressive risk factor modification.

Alternatives like a Coronary CT Angiography (CCTA) are considered when symptoms are present or there’s a higher pretest probability of obstructive disease. Stress imaging is preferred when the clinical question is about functional ischemia, not just atherosclerotic burden. For patients at clearly low or very high risk, the ASCVD pooled cohort risk calculator alone may be sufficient to guide decisions without imaging.

7. How Much Radiation Does a CT Coronary Calcium Score Deliver?

A frequent patient question is about radiation dose, and the CT Coronary Calcium Score is one of the lowest-dose CT studies performed. The estimated effective dose is typically between 0.5 and 1.5 mSv. This is a very low dose, comparable to the amount of natural background radiation a person receives in a few months.

The protocol is designed for low dose by using a prospective, ECG-triggered “step-and-shoot” acquisition, which only exposes the patient to radiation during a specific part of the cardiac cycle (mid-diastole), rather than continuously. This makes it a much lower-dose study than a full CCTA.

8. CT Coronary Calcium Score Imaging Protocol — Phases, Contrast, and Reconstructions

The protocol for a calcium score is standardized and straightforward. It is a non-contrast study that relies on precise ECG gating and, critically, a standardized tube voltage (kVp) to ensure the scoring algorithm is accurate and reproducible.

The scan acquires a single set of axial images from the level of the carina through the apex of the heart during a single ~10-second breath-hold. No contrast is administered. The key technical parameter is the use of 120 kVp, as the Agatston scoring system is calibrated to the Hounsfield units of calcium at this energy level. Using a different kVp would alter the measured density and produce an inaccurate score.

Common protocol pitfalls: The most critical error is deviating from 120 kVp. Lowering the kVp will artificially inflate the Hounsfield units of calcium, leading to a falsely elevated Agatston score. Ensure the scan is properly gated to mid-diastole to minimize cardiac motion artifact, which can blur calcifications and affect scoring accuracy.

9. The 3-Months-Free Offer for Radiology Residents and Fellows

3+ months free for radiology residents and fellows

Look like a rockstar on your reports — dictate positive findings in free form, and the AI generates a structured report using ACR + SIR templates with the appropriate clinical decision support firing automatically. This helps you create clear, consistent, and attending-ready reports faster, especially on busy calls or complex cases.

All we ask is feedback so we can keep improving the product for trainees.

To sign up, we just need three items:

1. Your PGY year (e.g., PGY-2, PGY-4)
2. Your training type (radiology residency or specific fellowship — IR, body, MSK, neuro, peds, breast, nucs)
3. Your training program / hospital name

Signup is simple. No credit card, no long forms. Just reply to the application with the three items above and we’ll get you set up. You can apply for the residents free-access program here.

10. Frequently Asked Questions

Is GigHz Precision AI HIPAA-compliant?

Yes. The platform is designed for de-identified workflows by default. No Protected Health Information (PHI) is required to use the tool for generating structured reports from your dictations.

Do I need my hospital’s IT department to set this up?

No. It’s a secure, browser-based application. There’s no software to install. You can use it on any hospital workstation, your personal laptop, or even the call-room iPad.

Does it work with PowerScribe or other dictation systems?

Yes. It works alongside any dictation system. You dictate as you normally would, and use the tool to help structure your findings and impression, which you can then copy into your final report in your PACS/RIS.

Can I use my own custom templates?

Yes, the system allows for customization. While it comes pre-loaded with ACR and SIR standard templates, you can modify them or add your own to match your personal or institutional preferences.

What happens after my residency or fellowship ends?

The free access is for trainees. After you graduate, you can transition to a standard attending plan. We offer discounts for recent graduates to help you get started in your new role.