Could the Bacterium Hiding in Gums Be Linked to Heart Rhythm Disorders?

New Delhi, May 17 (NationPress) Individuals grappling with gum disease might face a heightened risk of developing a heart rhythm disorder, commonly referred to as atrial fibrillation, based on recent research.

Researchers at Hiroshima University in Japan discovered that the bacterium responsible for gum disease, Porphyromonas gingivalis (P. gingivalis), can enter the bloodstream and reach the heart.

Once it infiltrates the heart, it subtly promotes the accumulation of scar tissue—altering the heart’s structure, disrupting electrical signals, and increasing the likelihood of atrial fibrillation (AFib)—a serious heart rhythm disturbance that could result in stroke, heart failure, and other critical health issues.

Globally, the incidence of AFib has nearly doubled in less than a decade, escalating from 33.5 million cases in 2010 to about 60 million by 2019. This growing body of evidence indicates that gum disease may be playing a role in this alarming trend.

The findings, published in the journal Circulation, present the first robust evidence that P. gingivalis from the gums can migrate to the left atrium in both animal models and humans, hinting at a possible microbial pathway linking periodontitis to AFib.

“While the causal link between periodontitis and atrial fibrillation remains unclear, the transmission of periodontal bacteria through the bloodstream may bridge these two conditions,” remarked Shunsuke Miyauchi, Assistant Professor at the university’s Graduate School of Biomedical and Health Sciences.

For this study, the team developed a mouse model using the bacterium's aggressive W83 strain. They divided 13-week-old male mice into two groups: one group had the strain introduced into the tooth pulp, while the other group was left uninfected.

Each group was further subdivided and monitored for either 12 or 18 weeks to assess the cardiovascular risks associated with prolonged exposure.

The results indicated no variation in AFib risk between infected and uninfected mice at the 12-week mark.

However, by the 18-week point, tests revealed that mice exposed to the bacterium were six times more likely to develop abnormal heart rhythms, exhibiting a 30 percent rate of AFib inducibility, compared to just 5 percent in the control group.

Additionally, the research team identified P. gingivalis in the heart’s left atrium, where infected tissue had become stiff and fibrous.

In contrast, the uninfected mice displayed healthy teeth with no signs of the bacterium in heart tissue samples.