New Research Links Infections to Heart Attacks
It seems germs could be causing even more harm than previously thought. Recent studies indicate that certain infections may play a role in triggering heart attacks.
Researchers from Finland and the UK investigated arterial plaques from individuals who had succumbed to heart disease, among others. They discovered that these plaques often housed a dormant bacterial biofilm layer. Furthermore, it appears that bacteria released from this biofilm might actually trigger heart attacks. While this is still a developing area of research, it could lead to new prevention or treatment methods for heart attacks in the future.
According to the paper, which appeared in the Journal of the American Heart Association, “This finding adds to the current conception of the pathogenesis of [heart attacks].”
The Role of Infection
Previous studies have suggested links between some infections and an increased risk of heart attacks, although pinpointing the exact processes has proven challenging.
The researchers analyzed arterial plaques—essentially harmful deposits that can accumulate in arteries—from people who died unexpectedly and those who underwent surgical plaque removal. By using various techniques, including genetic sequencing, they identified multiple types of bacteria typically found in the mouth embedded in these plaques.
These bacteria formed biofilms, which are dense clusters that resist the immune system and antibiotics more effectively than individual bacteria. The researchers observed that the biofilms deeply embedded in the plaques did not elicit an immune response. However, some plaques contained bacteria that had broken away from the biofilm, which did provoke an immune reaction leading to inflammation. Additionally, these released bacteria appeared to be connected to plaque ruptures and heart attacks.
Lead author Pekka Karhunen, a researcher at Tampere University in Finland, noted, “Bacterial involvement in coronary artery disease has long been suspected, but direct and convincing evidence has been lacking. Our study demonstrated the presence of genetic material—DNA—from several oral bacteria inside atherosclerotic plaques.”
The authors hypothesize that it may take a kind of double effect for these bacteria to cause heart issues. Typically, the biofilm remains concealed and inactive. But if, say, a secondary viral infection activates them, the bacteria can thrive and provoke the immune system, resulting in inflammation that can rupture the plaque. This ruptured plaque can then lead to blood clots that obstruct blood flow, potentially causing a heart attack.
Future Research Directions
While these findings are promising, they will require further validation by additional studies from different research groups. However, if confirmed, this research could provide fresh insights into combating heart disease.
The researchers suggest that giving a short antibiotic course to individuals whose heart attacks stem from these bacteria might enhance their recovery. In the long run, vaccines targeting these bacteria or common infectious triggers could help prevent heart attacks.
Interestingly, some studies have already indicated that people vaccinated against the flu, covid-19, and shingles may have a reduced risk of heart disease.
