Some heart attacks could be triggered by germs

The germs could be even worse for us that we did not think it. New research suggests that some infections could be a factor contributing to heart attacks.

Scientists from Finland and the United Kingdom conducted the study, which examined the arterial plates taken from people who died of heart disease and others. They found that these plates often contained a dormant layer of bacterial biofilm; They also found evidence that bacteria released from this biofilm can then trigger heart attacks. Although it is not yet final, the study can one day indicate another way that we can prevent or treat heart attacks, say the researchers.

“This observation adds to the current design of pathogenesis of (heart attacks),” wrote researchers in their article, published last month in the Journal of the American Heart Association.

A double blow of potential infection

Many studies have suggested that some infections can make us more vulnerable to a heart attack, also known as myocardial infarction. But according to study researchers, it was difficult to limit the exact mechanisms involved in this potential chain of events.

The researchers studied arterial plates – cholesterol deposits and other debris that can accumulate along our arteries – collected from people who are suddenly dead as well as patients who have had their surgically removed plate. Using various methods, including genetic sequencing, they have identified several groups of bacteria normally found in our mouths in these plates.

These bacteria had formed biofilms, robust and sticky layers of bacterial colonies. Bacteria inside a biofilm are much better to push the immune system and the antibiotics than they would be individually.

The researchers found that biofilms glued deep inside the plates did not trigger the immune system. But some plates contained bacteria shaken with biofilm, and these bacteria seemed to trigger an immune response and resulting inflammation. In addition, the presence of these liberated bacteria also seemed to be associated with broken plates and heart attacks.

“Bacterial involvement in coronary diseases has long been suspected, but direct and convincing evidence has been lacking. Our study demonstrated the presence of genetic material – DNA – of several oral bacteria within atherosclerotic plates, “said the main author Pekka Karhunen, a researcher at Tampere University in Finland, in a University Declaration.

The authors say that it can take a kind of double blow for these bacteria to arouse heart problems. As a rule, the biofilm inside these plates remains hidden and sleeping. But when something else activates bacteria – like a secondary viral infection – bacteria develop and trigger the immune system, causing inflammation that opens the plate. The broken plate can then produce clots that block the blood flow of the artery, causing a heart attack.

Unanswered questions and new avenues

The results of the team must be validated by additional studies, ideally with other research teams. But if it is confirmed, their work could certainly help us better fight against heart disease.

It is possible, according to the researchers, that giving a short antibiotic lesson to people whose heart attacks are caused by these bacteria could improve their results, for example. One day, we could even be able to reliably prevent heart attacks using vaccines against these bacteria or current secondary infectious triggers.

In particular, several studies have already suggested that people vaccinated against flu, COVID-19 and shingles have a lower risk of heart disease.