Are sex-specific thresholds needed for coronary CT?
As coronary CT angiography (CCTA) becomes increasingly important in assessing coronary artery disease (CAD), growing evidence suggests that applying the same thresholds to men and women may not fully capture differences in disease biology and risk.
Purvi Parwani, MD, MPH, a cardiologist, assistant professor of medicine and director of the Women’s Heart Health Clinic at Loma Linda University Health, discussed the emerging evidence around sex-specific thresholds for coronary plaque, stenosis and fractional flow reserve derived from CT (FFR-CT) during the 2026 Society of Cardiovascular Computed Tomography (SCCT) meeting. She shared some of takeaways with Cardiovascular Business in the above video interview.
Parwani said data from the CONFIRM 2 and PROMISE trials have shown that women generally have a lower overall plaque burden than men. However, after menopause, plaque burden increases. More importantly, when women have a similar degree of coronary stenosis as men, the plaque may carry greater risk.
This all raises the question of whether CCTA measures should have different thresholds for women.
FFR-CT presents another potential area for reconsideration. Data from the ADVANCE registry have suggested that women with FFR-CT values between 0.75 and 0.80, the commonly recognized gray zone, were less likely to have obstructive disease and often do not need revascularization. Parwani said a better cutoff for considering revacdularization might be at values below 0.75.
Yet simply lowering or changing thresholds for women could create another problem, Parwani said. Women have substantially higher rates of ischemia with non-obstructive coronary arteries (INOCA), which is the result of microvascular dysfunction, vasospasm or other differences in coronary physiology.
“Plaque is just not a binary threshold,” Parwani said. “Plaque is more of a continuum. It's a continuum of risk.”
Currently, professional societies generally use the same 0.80 FFR threshold for men and women. Parwani said there is evidence that values between approximately 0.70 and 0.80 require greater clinical context, regardless of sex.
Rather than simply establishing separate “male” and “female” cutoffs, she believes the future may lie in combining multiple patient characteristics into more sophisticated risk models.
“We really cannot fit our biology in a binary threshold,” she said, explaining disease is more complex than that with many variables involved.
Artificial intelligence could help by integrating CCTA plaque characteristics with physiological measurements, inflammation, microvascular assessment, genomics and other clinical information. In this approach, sex would be one component of a broader assessment rather than the sole determinant of a treatment threshold.
Parwani acknowledged that women’s cardiovascular biology is sufficiently different to warrant greater attention in guidelines, but said there are not yet enough validated datasets to establish definitive sex-specific CCTA thresholds. She said more research is needed in this area.
The challenge is further complicated by changes in women’s physiology throughout their lives. A single threshold may not be appropriate for a pregnant woman, a premenopausal woman, a postmenopausal woman or other populations with distinct biological characteristics.
“We need some guidance, but right now we don't have that much validated data,” Parwani said. “Biology is really gray and we cannot be painting it with pink cutoffs.”
For now, she advocates a more nuanced interpretation of CCTA findings rather than relying exclusively on binary thresholds. As AI and multimodal cardiovascular assessment advance, she sees an opportunity to move from demographic-based cutoffs toward individualized, biology-based risk assessments.
Dave Fornell has covered healthcare for more than 17 years, with a focus in cardiology and radiology. Fornell is a 5-time winner of a Jesse H. Neal Award, the most prestigious editorial honors in the field of specialized journalism. The wins included best technical content, best use of social media and best COVID-19 coverage. Fornell was also a three-time Neal finalist for best range of work by a single author. He produces more than 100 editorial videos each year, most of them interviews with key opinion leaders in medicine. He also writes technical articles, covers key trends, conducts video hospital site visits, and is very involved with social media. E-mail: [email protected]