Cardiovascular disease is the leading cause of death and disability in the world, killing 17.7 million people a year. That's a third of all deaths on the planet and half of all non-communicable-disease-related deaths. Cardiac imaging and vascular imaging are critical in foreseeing an event before it happens.
A coronary CT angiography (coronary CTA) uses an injection of iodine-rich contrast material and CT scanning to examine the arteries that supply blood to the heart and determine whether they have been narrowed by plaque buildup.
CAD-RADS™ – Coronary Artery Disease Reporting and Data System – is the language radiologists are developing to standardize the way we communicate with clinicians about coronary CT angiography (coronary CTA), facilitating better care decisions for cardiac patients.
The concept of a standard reporting and data system for a given pathology is not new, but the success of this approach has dramatically improved the speed and accuracy of diagnoses for other disorders, enabling faster, more informed treatment plans. It is time to apply the approach to coronary disease.
BI-RADS, the Breast Imaging Reporting and Data System, was first introduced in 1993 for mammography interpretations. Periodic refinements over its lifespan have evolved BI-RADS into an indispensible tool in advancing the detection and treatment of breast cancer. It has also inspired the successful development of other pathology-driven lexicons.
Following the BI-RADS model, we anticipate CAD-RADS will enhance communication between radiologists and clinicians regarding complex coronary CTA. The benefits include:
Coronary stenosis occurs when the coronary artery narrows due to plaque build-up. Eventually, this leads to limited blood supply to the heart muscle, and this can cause symptoms like chest pain as well as possibly heart attacks. Your treatment depends on the severity of your condition. CAD-RADS first categorizes coronary CTA images by coronary stenosis severity, using the Society of Cardiovascular CT (SCCT) classification system noted in the below table.
SCCT grading scale for stenosis severity
| Degree of luminal diameter stenosis | Terminology | CAD-RADS category |
| 0% | No visible stenosis | 0 |
| 1-24% | Minimal stenosis | 1 |
| 25-49% | Mild stenosis | 2 |
| 50-69% | Moderate stenosis | 3 |
| 70-99% | Severe stenosis | 4 |
| 100% | Occluded | 5 |
Then, based on whether the patient is presenting with stable chest pain or acute chest pain*, the radiologist may provide a clearly-defined interpretation, with guidelines for further cardiac investigation if necessary, and recommendations for emergent care or non-emergency treatment options.
*Acute chest pain, negative first troponin, negative or non-diagnostic electrocardiogram and low to intermediate risk (TIMI risk score <4) in emergency department or hospital setting.
Complete CAD-RADS categorization and guidelines are published in the Journal of Cardiovascular Computed Tomography. [Cury RC, et al., CAD-RADS™ Coronary Artery Disease e Reporting and Data System. An expert consensus document of the Society of Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR) and the North American Society for Cardiovascular Imaging (NASCI). Endorsed by the American College of Cardiology. 2016]
Include CAD-RADS classification in every coronary CTA examination and final assessment. Educate Residency and Fellowship trainees in CAD-RADS terminology, assessment categories and management recommendations.
Through new scientific data, expert guidance from leaders in cardiac imaging, and a multi-disciplinary effort among radiology and cardiology societies, CAD-RADS will continue to evolve. As it does, we will speak the language of better education, compliant research, and more productive peer-review, with the ultimate goal of improved patient care.