Hidden Bacteria Linked To Heart Attacks, Landmark Study Reveals

A new study suggests that infectious diseases may also act as triggers for myocardial infarction, commonly known as heart attacks. The research indicates that dormant bacteria could play a decisive role in causing the condition.

Conducted by scientists in Finland and the UK, the study challenges traditional thinking on the origins of heart attacks. It highlights fresh opportunities for treatment, improved diagnostic methods, and even future vaccine development.

Professor Pekka Karhunen of Tampere University in Finland, who led the work, explained that until now researchers believed coronary artery disease developed only through oxidised low-density lipoprotein (LDL), which the body recognises as foreign.

Karhunen noted, “Bacterial involvement in coronary artery disease has long been suspected, but direct and convincing evidence has been lacking.”

The study, published in the ‘Journal of the American Heart Association’, has shown that infection may serve as a trigger for myocardial infarction.

Researchers discovered that cholesterol-rich atherosclerotic plaques in coronary artery disease can conceal biofilms – gelatinous structures formed silently by bacteria over many years.

Within these biofilms, bacteria remain dormant, protected from both immune defences and antibiotics, which cannot penetrate the biofilm shield.

However, a viral infection or other external factors can awaken these biofilms, enabling bacterial growth and prompting inflammation.

This inflammatory reaction may rupture the fibrous cap of a plaque, leading to clot formation and eventually heart attack.

According to the researchers, “Our study demonstrated the presence of genetic material — DNA — from several oral bacteria inside atherosclerotic plaques.”

The team further confirmed their findings by developing a targeted antibody, which unexpectedly exposed biofilm structures in arterial tissue.

In cases of heart attack, bacteria released from these biofilms observed, triggering an immune response that caused inflammation and plaque rupture.

These insights mark a step forward in devising new strategies to diagnose and treat myocardial infarction. They also suggest that prevention through vaccination could one day be possible, the researchers concluded.