Daijiworld Media Network - New Delhi
New Delhi, May 18: A recent study has revealed a troubling link between gum disease and atrial fibrillation (AFib), a serious heart rhythm disorder that can lead to stroke, heart failure, and other critical complications.
Researchers from Hiroshima University in Japan have identified that Porphyromonas gingivalis (P. gingivalis), a key bacterium responsible for periodontitis (gum disease), can enter the bloodstream and travel to the heart. Once there, it contributes to the buildup of scar tissue in the heart's left atrium, disrupting normal electrical activity and significantly increasing the risk of AFib.
The findings, published in the journal Circulation, offer the first concrete evidence that a bacterium found in infected gums can directly infiltrate heart tissue in both humans and animal models. The implications point to a possible microbial pathway connecting chronic oral infections to serious cardiovascular conditions.
“The causal relationship between periodontitis and atrial fibrillation is still unclear, but the spread of periodontal bacteria through the bloodstream may link these conditions,” said Dr. Shunsuke Miyauchi, Assistant Professor at Hiroshima University’s Graduate School of Biomedical and Health Sciences.
To explore this connection, researchers developed a mouse model using the highly virulent W83 strain of P. gingivalis. Thirteen-week-old male mice were divided into infected and uninfected groups. These groups were further monitored for either 12 or 18 weeks to examine the long-term cardiovascular effects.
At the 12-week mark, researchers observed no significant differences in heart rhythm. However, by week 18, the results were striking — 30% of the infected mice displayed AFib-like symptoms, compared to just 5% in the control group. That made the infected group six times more likely to develop arrhythmias.
Post-experiment tissue analysis revealed hardened, fibrous scarring in the left atria of infected mice, where P. gingivalis had embedded itself. In contrast, the control mice showed no presence of the bacteria and maintained healthy heart tissue.
Globally, the number of AFib cases has nearly doubled in a decade — rising from 33.5 million in 2010 to around 60 million by 2019 — prompting scientists to investigate previously overlooked contributing factors such as oral health.
This study adds to the growing body of evidence suggesting that maintaining good dental hygiene may play a critical role in preventing serious heart conditions, underscoring the importance of integrated healthcare approaches.