Tag: coronary artery calcium

Opportunistic Screening Takes Big Step Forward

Posted on by Brian Casey

Opportunistic screening took a big step forward this week with new research in Nature Scientific Reports showing how an AI algorithm from Riverain Technologies was able to calculate coronary artery calcium scores from non-contrast CT scans – with performance close to that of radiologists. 

Opportunistic screening gives radiologists the chance to detect clinical conditions other than those for which the original scan was ordered. 

  • Potential use cases include calculating cardiovascular risk from mammograms or undiagnosed osteoporosis from CT exams.

One of the opportunistic applications with the most potential is CAC scoring from CT scans. 

  • CAC scores are a good marker for future cardiovascular risk. But it can be time-consuming to perform separate cardiac CT scans just to acquire CAC data when thousands of abdominal and thoracic CT studies are conducted every day and could serve just as well.

Riverain’s ClearRead CT CAC algorithm uses AI to analyze non-contrast CT exams and produce Agatston scores, the reference standard for CAC analysis. 

  • Previous research found Agatston scores to be predictive for both cardiovascular and all-cause mortality, but generating the scores requires some manual involvement from clinicians. 

In the new study, Mass General Brigham researchers compared ClearRead CT CAC’s performance to ground-truth calculations from radiologists in 491 patients who got non-contrast CT scans at five U.S. hospitals in 2022 and 2023. Researchers found…

  • CAC score agreement between AI and radiologists was high, with a kappa of 0.959 (1.0 is perfect agreement).
  • The association remained strong regardless of sex, age, race, ethnicity, and CT scanner model, with kappa higher than 0.90 for all groups except “other race.” 
  • The AI model’s CAC scores from non-gated CT scans were similar to those from gated cardiac CT exams (kappa = 0.906), which are generally considered the gold standard for cardiac CT but are more complex to perform.
  • The model’s kappa for gated CT exams compared favorably to recent research conducted with other commercially available algorithms.

The results are a boost for opportunistic screening but in particular for Riverain, which got FDA clearance for ClearRead CT CAC in December 2024 and offers the solution as part of its ClearRead CT suite.

The Takeaway

The new results show that opportunistic screening is moving beyond the research phase and that the opportunity could be now for real-world clinical use. 

CAC Research Leads Imaging at AHA 2025

Posted on by Brian Casey

The 2025 American Heart Association annual conference wraps up today, and cardiac imaging has been a major focus in New Orleans. In particular, research has highlighted imaging’s power to predict future cardiac events – and guide treatment to prevent them. 

Coronary artery calcium scoring with CT is a great example, as CAC scores can predict not only cardiovascular but also all-cause mortality. 

  • Another common theme at AHA 2025 has been opportunistic screening, in which data from imaging exams acquired for other clinical indications can be used to detect osteoporosis, cardiovascular disease, and other issues. 

Check out the items below for some of the hottest imaging topics at AHA 2025, and for a deeper dive into non-imaging news from New Orleans, be sure to visit our Cardiac Wire sister site. 

News from the show’s first three days include…

  • A massive study of 40k people found that those with CT-derived CAC scores greater than 0 were 2X-3X more likely to die from any cause than people without any CAC – and more died of causes other than cardiovascular disease. Also, 8.5% of patients had other significant findings. 
  • Community health personnel on a Native American reservation were trained to perform point-of-care screening echocardiography assisted by Us2.ai’s AI algorithms. 
  • Us2.ai’s algorithm was also used with transthoracic echo in the SCAN-MP study to detect transthyretin amyloid cardiomyopathy, a cause of heart failure. 
  • Treadmill stress tests fell short compared to CCTA in screening older master’s athletes for ischemia that could lead to sudden cardiac death.
  • A program in Brazil that used echocardiography to screen schoolchildren for latent rheumatic heart disease led to lower prevalence rates after 10 years (2.5% vs. 4.5%). 
  • Patients with hypertrophic cardiomyopathy who had higher levels of myocardial fibrosis on cardiac MRI were almost 6X more likely to have adverse events over eight years.
  • HeartLung Technologies’ AI tool predicted CAC presence on CT scans in 2.1k participants in the MESA study with higher AUC than other tools (AUC = 0.73 vs. 0.68).
  • Another study used HeartLung’s AI to analyze CAC scans to detect myosteatosis – a sign of systemic metabolic dysfunction – which predicted atrial fibrillation and heart failure. 
  • A program promoting CAC scoring to an urban population brought in people for screening who might have been missed through physician referral. 

The Takeaway

This week’s news from AHA 2025 shows medical imaging’s contribution to early detection of cardiovascular disease – the leading cause of death worldwide. CT-based CAC scoring has especially promising potential, not only for heart disease but also other conditions through opportunistic screening.

CAC Scoring Shines at ACC 2025

Posted on by Brian Casey

The American College of Cardiology’s annual meeting is wrapping up today in Chicago, and new research into coronary artery calcium scoring has been one of cardiac imaging’s top trends at McCormick Place.

CAC scoring has been around for ages as a way to detect and quantify calcium buildup in the coronary arteries based on data from non-contrast CT scans. 

  • But it’s only been in recent years that CAC scoring has come into its own as a tool for predicting risk of mortality and major cardiac events – in some cases years before they happen. 

Clinicians are learning that they can use CT-generated CAC scores to estimate future risk and guide interventions to reduce it, such by prescribing statins or behavior modifications. 

Research presented at ACC 2025 underscored CAC scoring’s potential …

  • In the CLARIFY CAC screening program, researchers found a 6.2% rate of thoracic aneurysm, indicating a need for screening and prevention.
  • CAC scores of 0 were more common in women than men (49% vs. 23%), but there was no statistically significant difference in non-calcified plaque rates between genders.
  • Researchers found moderate accuracy (AUC range=0.60-0.73) for a method of generating CAC scores from 12-lead ECG data rather than non-contrast CT scans.
  • Bunkerhill Health’s I-CAC algorithm was used to generate automated CAC scores for 200 patients. After six months, patients with scores >400 had a 17% rate of cardiac events and 11% all-cause mortality. 
  • A commonly used measure for low-value care based on administrative claims classified too many CAC tests as inappropriate, with a positive predictive value of only 43%.
  • A case study focused on the paradox of a 59-year-old healthy triathlete with a CAC score of 780, possibly due to chronic coronary stress from high-endurance exercise. Invasive testing was deferred in favor of medical therapy due to his low cardiac risk.
  • On the other hand, a literature review of 19.4k people found no statistically significant difference in CAC scores between endurance athletes and healthy controls.
  • Non-calcified plaque in patients with CAC scores of 0 was common (26%) in residents of rural Appalachia, indicating high risk of rupture and suggesting the limitation of relying on CAC scores. 
  • A Sunday debate discussed whether CAC scoring should be added to mammography and colon cancer screening, or reserved as a decision aid. 

The Takeaway

The studies from ACC 2025 show that CAC scoring has a bright future – bright enough that it’s generating heightened interest from cardiology. New CAC scoring tools arriving on the market should improve its predictive value even more. 

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