Tag: heart disease

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. 

Opportunistic Screening’s AI Milestone

Posted on by Brian Casey

A new study lays the groundwork for AI-based opportunistic screening – the detection of disease using medical images acquired for other indications. In a paper in AJR, researchers show how their homegrown AI algorithm was able to analyze abdominal CT scans and link body composition measurements to the presence of disease.

Opportunistic screening is a sort of holy grail for radiology, with the potential to help radiologists find pathology from scans ordered for other clinical indications. 

  • Some researchers specifically are focusing on analysis of body composition characteristics derived from CT scans like muscle, fat, and bone that could be biomarkers for hidden pathology – and AI is key because it can process mountains of patient data without getting tired.

In the new paper, researchers from the NIH and the University of Wisconsin tested the concept of AI-based body composition analysis on a massive database of 118k patients who got abdominal CT scans from 2000 to 2021. 

  • They analyzed the scans with their own internally developed AI tool that measures 13 features of body composition, from volume and attenuation in different organs to area of subcutaneous adipose tissue. 

Their goal was to correlate the AI measurements with actual presence of disease, as well as other factors that could affect body composition like age and sex. They found …

  • AI-based body composition metrics varied by age and sex, confirming previous studies.
  • AI metrics also correlated with the four systemic diseases studied, specifically cancer, cardiovascular disease, diabetes mellitus, and cirrhosis.
  • The predictive power of different metrics varied by disease, from a high of 13 measures for diabetes to a low of nine for cancer. 

What’s the real-world impact of the study? 

  • In addition to validating the concept of AI-based opportunistic screening on a broad scale, the findings could be used to establish a set of normal values for body composition that also take into account the impact of systemic disease on these measurements.

The Takeaway

The new study is a bit technical, but it’s an important milestone on the path to opportunistic screening. It not only demonstrates the concept’s feasibility, but also begins to establish the normal values needed to actually implement screening programs in the real world.

Two-for-One CT Screening Hits the Road

Posted on by Brian Casey

A new study takes CT screening on the road in rural Appalachia, showing how a mobile van outfitted with a CT scanner can screen at-risk individuals for both lung cancer and cardiovascular disease in one visit. 

Recent studies have demonstrated the effectiveness of CT lung cancer screening not only among the overall population, but particularly among disadvantaged communities with lower healthcare access. 

  • Such limited access is common in rural areas of Appalachia, which also have some of the highest rates of smoking and cardiovascular disease in the U.S.

Researchers from West Virginia University wanted to tackle two challenges at once with LUCAS, a mobile van outfitted with a CT scanner for lung cancer screening. 

  • They noted that CT lung scans can also be used to acquire data on coronary artery calcium (CAC), a known risk factor for cardiovascular disease. 

LUCAS was launched in September 2021, so WVU researchers analyzed data acquired for 526 low-dose CT screenings of high-risk people conducted through December 2022. 

  • They used the CT lung scans to calculate CAC scores based on Agatson criteria, in which a score of 101-400 indicates moderate risk of cardiovascular disease and >400 is classified as high risk; individuals with scores ≥100 should be referred to aspirin or statin therapy. 

They found that LUCAS scans revealed … 

  • Over 54% of patients had coronary calcification on LDCT scans
  • 31% of patients had CAC scores ≥100 
  • 14% had CAC scores ≥400
  • Elevated CAC scores correlated with lung cancer risk based on Lung-RADS scores as well as smoking history based on pack-years
  • Of the patients with CAC scores ≥1 and who weren’t already on statin or aspirin therapy, 6.2% started statins and 3.3% started aspirin

Despite the firm link between CAC scores and lung cancer risk, the researchers expressed disappointment that so few patients started prevention therapy like statins or aspirin after their exams.

  • Indeed, researchers noted that few patients from the study got additional cardiac testing or follow-up referrals for cardiovascular prevention after their screenings. 

The Takeaway

The new study not only confirms recent research showing that opportunistic screening can enhance the value of CT lung cancer scans, but also the role that lung exams can play in reducing healthcare disparities. On the down side, it shows that all the screening in the world won’t make a difference if patients don’t get appropriate follow-up. 

AI of Cardiac CT Predicts Risk

Posted on by Brian Casey

In a landmark study of 40k patients from the UK published in The Lancet, an AI-derived score that analyzed coronary arterial inflammation on coronary CT angiography scans was effective in predicting future cardiac risk in people regardless of whether they had obstructive coronary artery disease.

CCTA’s power for predicting heart problems has been demonstrated in multiple studies, and it’s now considered a first-line test for individuals with chest pain. 

  • But the situation is trickier in those without obstructive disease – prompting researchers to ask whether CCTA’s ability to visualize subtle changes in cardiac structure and function could be leveraged – such as with AI – to deliver even more prognostic power. 

The Oxford Risk Factors And Noninvasive imaging (ORFAN) study in the UK is addressing that question by conducting CCTA scans in 40k patients as part of routine clinical care at eight hospitals. 

  • Researchers analyzed outcomes in the entire ORFAN population of 40k patients, then followed a subset of 3.4k higher-risk patients for 7.7 years to study the value of a perivascular fat attenuation index (FAI) score. 

FAI scores measure heart inflammation in coronary arteries and are calculated using Caristo Diagnostics’ CaRi-Heart AI software.

  • The scores are combined with other traditional risk factors to create an AI-Risk classification that predicts the likelihood of an adverse event.  

Researchers found that … 

  • Across the entire 40k cohort, patients without obstructive CAD accounted for 64% of cardiac deaths and 66% of MACE – twice as many as those with obstructive CAD
  • In the smaller higher-risk cohort, patients with an elevated FAI score in all three coronary arteries had a higher risk of cardiac mortality (HR=29.8) or MACE (HR=12.6)
  • Elevated FAI scores in any coronary artery also predicted cardiac mortality
  • AI-Risk scores were associated with cardiac mortality (HR=6.75) and MACE (HR=4.68) when comparing very-high-risk versus low- or medium-risk patients 

The first data point is worth noting, as it illustrates the need to improve risk stratification and management in people without obstructive CAD.

The Takeaway
The ORFAN results are an exciting development for cardiac CT AI (in addition to being a major coup for Caristo, which raised $16.3M last year to commercialize CaRi-Heart globally). Measurements of coronary inflammation could give clinicians another tool – in addition to plaque measurements and calcium scoring – to predict cardiac events.

More Support for Cardiac CT’s Value

Posted on by Brian Casey

A new study in Radiology offers more support for the value of CT-based coronary artery calcium scoring, finding that people with higher CAC scores had worse outcomes, and suggesting that those with scores of 0 could potentially avoid invasive coronary angiography. 

Evidence has been building that by measuring calcium buildup in the heart, CAC scores can predict clinical outcomes, in particular major adverse cardiac events, particularly in patients with stable chest. 

  • Studies ranging from MESA to SCOT-HEART to PROMISE have found that patients with CAC scores of 0 have MACE risk that’s lower than 2% – meaning they could be discharged without further invasive workup. 

The new study is an update to the DISCHARGE trial, which in 2022 published results comparing a CT-first evaluation strategy to one with invasive coronary angiography. The new study investigates the value of CAC scoring by analyzing its prognostic power in patients with stable chest pain who were referred for invasive coronary angiography. 

  • The DISCHARGE study is notable for its diversity – 26 clinical centers in 16 European countries – as well as its use of 13 different models of CT scanners from all four major CT OEMs from 2015 to 2019. 

In all, 1.7k patients were studied, and CAC scores were generated based on CT scans and used to stratify patients into one of three groups; they were then followed for 3.5 years and rates of MACE were correlated to CAC levels, finding … 

  • Patients with CAC scores of 0 had the lowest rates of MACE compared to those with scores of 1-399 and ≥400 (0.5% vs. 1.9% & 6.8%)
  • Rising CAC scores corresponded to higher prevalence of obstructive coronary artery disease (0=4.1% vs. 1-399=29.7% & ≥400=76%)
  • Revascularization rates rose with CAC scores (0=1.7% vs. ≥400=46.2%)

While the authors steered away from commenting on the study’s impact on clinical management, the findings – if confirmed with additional studies – suggest that stable chest pain patients may not need invasive coronary angiography.

  • And in another interesting wrinkle to the study, the researchers pointed out that 57% of the DISCHARGE study’s patient population were women, a fact that addresses sex bias in previous research. 

The Takeaway

The DISCHARGE study’s findings are yet another feather in the cap for cardiac CT, with higher CAC scores indicating the long-term presence of atherosclerosis. Should they be confirmed, individuals with stable chest pain in the future will benefit from less invasive – and less expensive – management.

CT First for Chest Pain

Posted on by Brian Casey

CT should be used first to evaluate patients with stable chest pain who are suspected of having a heart attack. That’s the message of a paper being presented this week at the American College of Cardiology Cardiovascular Summit in Washington, DC.

CT is proving itself useful for a variety of applications in cardiac imaging, from predicting heart disease risk through coronary calcium scores to assessing whether people with chest pain need treatment like invasive angiography – or can be sent home and monitored.

  • But cardiac CT often runs up against decades of clinical practice that relies on tools like stress testing or diagnostic invasive coronary angiography for evaluating patients, with the CT-first strategy reserved for a limited number of people, such as those with unestablished coronary artery disease. 

But the new study suggests that the CT-first approach could be used for the vast majority of patients presenting with stable chest pain. 

  • A research team led by senior author Markus Scherer, MD, of Atrium Health-Sanger Heart & Vascular Institute in Charlotte, North Carolina tested the strategy in 786 patients seen from October 2022 to June 2023 who had no prior diagnosis of coronary artery disease and underwent elective invasive angiography to evaluate suspected angina.

The CT-first strategy compared CT angiography with provisional FFRCT testing to traditional evaluation pathways, which included stress echo, stress myocardial perfusion imaging, stress MRI, or no invasive testing before direct referral to angiography. Revascularization rates by strategy were as follows … 

  • 62% for CT-first
  • 50% for stress MRI
  • 40% for stress echo
  • 34% for no prior test
  • 31% for stress MPI

The Takeaway

The results presented this week offer real-world evidence that support recent clinical studies backing broader use of CT for patients with chest pain. Given CT’s advantages in terms of cost and noninvasiveness, the findings raise the question of whether more can be done to get clinicians to adhere to established guidelines calling for a CT-first protocol. 

Fine-Tuning Cardiac CT

Posted on by Brian Casey

CT has established itself as an excellent cardiac imaging modality. But there can still be some fine-tuning in terms of exactly how and when to use it, especially for assessing people presenting with chest pain. 

Two studies in JAMA Cardiology tackle this head-on, presenting new evidence that supports a more conservative – and precise – approach to determining which patients get follow-up testing. The studies also address concerns that using coronary CT angiography (CCTA) as an initial test before invasive catheterization could lead to unnecessary testing.

In the PRECISE study, researchers analyzed 2.1k patients from 2018 to 2021 who had stable symptoms of suspected coronary artery disease (CAD). Patients were randomized to a usual testing strategy (such as cardiac SPECT or stress echo), or a precision strategy that employed CCTA with selected fractional flow reserve CT (FFR-CT). 

The precision strategy group was further subdivided into a subgroup of those at minimal risk of cardiac events (20%) for whom testing was deferred to see if utilization could be reduced even further. In the precision strategy group….

  • Rates of invasive catheterization without coronary obstruction were lower (4% vs. 11%)
  • Testing was lower versus the usual testing group (84% vs. 94%)
  • Positive tests were more common (18% vs. 13%)
  • 64% of the deferred-testing subgroup got no testing at all
  • Adverse events were higher, but the difference was not statistically significant

To expand on the analysis, JAMA Cardiology published a related study that further investigated the safety of the deferred-testing strategy at one-year follow-up. Researchers compared adverse events in the deferred testing group to those who got the usual testing strategy, finding that the deferred testing group had…

  • A lower incidence rate of adverse events (0.9 vs. 5.9)
  • A lower rate of invasive cardiac cath without obstructive CAD per 100 patient years (1.0 vs. 6.5)

The results from both studies show that a strategy of deferring testing for low-risk CAD patients while sending higher-risk patients to CCTA and FFR-CT is clinically effective with no adverse impact on patient safety.

The Takeaway
The new findings don’t take any of the luster off cardiac CT; they simply add to the body of knowledge demonstrating when to use – and not to use – this incredibly powerful tool for directing patient care. And in the emerging era of precision medicine, that’s what it’s all about.

Is CCTA Set for Cardiac Screening?

Posted on by Brian Casey

A new study out of Denmark suggests that coronary CTA could be headed for population-based screening for heart disease. Researchers found that CCTA was remarkably effective in identifying individuals without symptoms who were more likely to experience heart attacks in years to come.

CCTA has proven so effective for cardiac imaging that it’s become a first-line test for stable chest pain, usually for those with symptoms. But researchers have debated whether CCTA’s value could be extended to asymptomatic individuals – which could set the stage for broad-based heart disease screening programs.

To investigate CCTA’s potential in the asymptomatic, researchers in Denmark scanned 9,533 individuals 40 years and older as part of the Copenhagen General Population Study, reporting their results in Annals of Internal Medicine. CCTA scans were conducted with Canon Medical’s 320-detector-row Aquilion One Vision scanner. 

Atherosclerosis was characterized as either obstructive (a luminal stenosis ≥ 50%), extensive (stenoses widely prevalent but not obstructive), or both. Researchers then tracked myocardial events over a median follow-up of 3.5 years. 

They found that 46% of study subjects had evidence of subclinical coronary atherosclerosis, with the type of atherosclerosis impacting risk of myocardial infarction: 

  • Extensive atherosclerosis had eight times higher risk 
  • Obstructive atherosclerosis had nine times higher risk
  • Both extensive and obstructive disease had 12 times higher risk

What’s more, researchers found that 10% of their study population had obstructive disease – which is just 10 percentage points under the 60% atherosclerosis threshold at which therapeutic intervention should be considered for asymptomatic people. 

Participants in the CGPS study did not receive treatment as part of the study, but the researchers have a follow-up study underway – DANE-HEART – in which asymptomatic people will get CCTA scans and some will be directed to preventive treatment if they meet clinical guidelines.

The Takeaway

This study demonstrates not only the widespread incidence of subclinical coronary atherosclerosis, but also CCTA’s ability to detect CAD before symptoms appear. Preventive treatment initiated and directed by CT findings could have a major impact on heart disease morbidity and mortality.

Given CCTA’s prognostic ability and the heavy burden of heart disease on society (more women die of heart disease than breast cancer, for example), how long before calls emerge to add CT-based heart screening to the arsenal of population-based screening programs? DANE-HEART may offer a clue.

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