Scientists have uncovered a biological mechanism that could explain the long-observed link between gum disease and heart problems; the same bacteria that cause severe periodontitis can travel through the bloodstream and directly trigger calcium buildup in the aortic valve.
The findings, presented at the American Heart Association’s Basic Cardiovascular Sciences meeting in July 2026, offer what researchers describe as a potential “missing link” between oral health and calcific aortic valve disease (CAVD), a condition affecting millions worldwide that stiffens and narrows the heart’s aortic valve.
Dr. Chenyang Li of Fuwai Hospital in Beijing, the study’s first author, and colleagues analyzed calcified aortic valves removed during valve-replacement surgery and compared them with non-calcified valves. The results were striking: Porphyromonas gingivalis, a bacterium best known for causing severe gum disease, was about 30 times more abundant in the calcified valves, both in terms of bacterial DNA and proteins.
“This suggests that P. gingivalis may directly contribute to valve disease, beyond traditional cardiovascular risk factors,” Li said.
From gums to valves
The proposed pathway follows a logical sequence. P. gingivalis thrives in the deep pockets that form between gums and teeth in periodontitis. Routine activities such as brushing, flossing, or chewing can push the bacteria into the bloodstream. Once circulating, they can lodge in the aortic valve, a small, three-flapped structure that regulates blood flow from the heart into the aorta.
Once there, the bacteria trigger local inflammation. This stimulates production of interleukin-1 beta, a signaling molecule that acts as a molecular switch. The inflammatory signal causes valve cells to change identity, essentially behaving more like bone-building cells. These transformed cells begin depositing calcium in the valve tissue, the hallmark of CAVD.
The team tested this mechanism in multiple ways. In mice, injecting live P. gingivalis led to bacteria finding their way to the aortic valve, causing inflammation, calcium deposition, and measurable valve narrowing. Treating mice with antibiotics before bacterial injection reduced the amount of bacteria reaching the valve and slowed disease progression. Injecting dead bacteria produced no effect.
“We were surprised to see valve calcification even in mice without high cholesterol,” Li noted, suggesting the bacteria can drive the disease independently of classical risk factors.
In cell-culture experiments using human valve cells, P. gingivalis exposure increased both inflammation and calcium buildup. Blocking interleukin-1 beta significantly reduced these effects, pointing to a potential therapeutic target.
More than wear and tear
CAVD has traditionally been viewed as a passive, age-related condition, the mechanical wear and tear of decades of heartbeats slowly stiffening the valve. But that understanding has been shifting.
“The findings fit well with our current understanding of calcific aortic valve disease as an active, inflammation-driven disease rather than simply wear and tear of the valve,” said Dr. Elena Aikawa of Harvard Medical School, who was not involved in the study.
The condition affects 2–7% of adults over 65, according to the American College of Cardiology. There are no approved drugs that can slow its progression. Severe cases require valve-replacement surgery, an invasive procedure with significant risks for elderly patients.
Caveats apply
The research has important limitations. The human data comes from tissue removed during surgery, a snapshot in time that cannot prove the bacteria caused the calcification, only that they are associated with it.
Dr. Richard Lamont of the University of Louisville School of Dentistry, who was not part of the study, pointed out a significant animal-model limitation: “Mice have very different oral microbiomes than humans, making it difficult to know whether the exact same process occurs in people.”
The findings have not yet been peer-reviewed; they were presented at a scientific meeting, which is common for early-stage work in cardiology. Some experts noted that periodontal disease is likely one contributor among many, and the bacterial link does not diminish the importance of established risk factors such as high cholesterol, smoking, and hypertension.
If confirmed, the interleukin-1 beta pathway could offer a target for drugs that slow or prevent valve calcification, an approach already being explored in other inflammatory heart conditions. The study also reinforces the practical importance of oral hygiene for cardiovascular health, a connection that dentists and cardiologists have observed for decades without a clear biological explanation.
The study was presented at the American Heart Association’s Basic Cardiovascular Sciences Scientific Sessions 2026. It has not yet been published in a peer-reviewed journal.