UC Irvine Researchers Find Differences Between Two Causes of Heart Valve Narrowing

UC Irvine’s Arash Kheradvar (left) and Gregg Pressman of Jefferson Health and their teams collaborated on a project to underscore differences in two prevalent forms of mitral valve stenosis in the heart. The research will help improve the diagnosis and treatment of the heart condition that impacts as much as 15 percent of the population. Arash Kheradvar / UC Irvine
 

• UC Irvine and Jefferson Health investigators identify distinct structural and blood-flow signatures in two major forms of mitral stenosis.
• Findings highlight limitations of applying rheumatic-based diagnostic criteria to calcification-driven disease.
• The research was partially funded by the National Institutes of Health and the National Science Foundation.

Irvine, Calif., Jan. 22, 2026 — University of California, Irvine and Philadelphia-based Jefferson Health researchers have identified fundamental structural and functional differences between two major causes of mitral valve stenosis. This narrowing restricts blood flow through the heart. The findings challenge current diagnostic approaches and may help clinicians tailor treatment decisions for a growing patient population.

The study, published in the Journal of the American Heart Association, combined 3D ultrasound heart imaging with patient-specific laboratory modeling to show that stenosis caused by mitral annular calcification, or MAC, is different in terms of structure and blood flow dynamics from rheumatic mitral stenosis, the form on which many current diagnostic standards are based.

The researchers found that using diagnostics developed for rheumatic disease may underestimate or mischaracterize MAC-related mitral stenosis, potentially affecting clinical decision-making and treatment selection.

Mitral annular calcification affects an estimated 8 to 15 percent of the general population and is more common in older adults, patients with chronic kidney disease, and individuals with a history of chest radiation.

Despite its prevalence, mitral stenosis associated with mitral valve disease has not been well-characterized.  It’s often assessed using frameworks developed for rheumatic heart disease, though there are significant differences between the two, particularly in valve structure and blood flow constraints.

“For decades, mitral stenosis has been assessed using a one-size-fits-all approach,” said senior co-author of the study Arash Kheradvar, UC Irvine professor of radiological sciences, biomedical engineering and medicine. “But MAC-related stenosis behaves differently. The valve structure is different and blood flow patterns are different, and the relationship between anatomy and severity doesn’t follow the same rules.”

Read the full press release in UC Irvine News.