Finland's second-largest university has announced new research suggesting that heart attacks could be an infectious disease. [T]he research found that, in coronary artery disease, atherosclerotic plaques containing cholesterol may harbor a gelatinous, asymptomatic biofilm formed by bacteria over years or even decades. Dormant bacteria within the biofilm remain shielded from both the patient's immune system and antibiotics because they cannot penetrate the biofilm matrix. A viral infection or another external trigger may activate the biofilm, leading to the proliferation of bacteria and an inflammatory response. The inflammation can cause a rupture in the fibrous cap of the plaque, resulting in thrombus [blood clot] formation and ultimately myocardial infarction... "Bacterial involvement in coronary artery disease has long been suspected, but direct and convincing evidence has been lacking," explains professor Pekka Karhunen [who led the study with researchers from the UK and Finland]. "Our study demonstrated the presence of genetic material — DNA — from several oral bacteria inside atherosclerotic plaques." The findings were validated by developing an antibody targeted at the discovered bacteria, which unexpectedly revealed biofilm structures in arterial tissue. Bacteria released from the biofilm were observed in cases of myocardial infarction. The body's immune system had responded to these bacteria, triggering inflammation which ruptured the cholesterol-laden plaque. The observations pave the way for the development of novel diagnostic and therapeutic strategies for myocardial infarction. Furthermore, they advance the possibility of preventing coronary artery disease and myocardial infarction by vaccination. "The research is part of an extensive EU-funded cardiovascular research project involving 11 countries..."Read more of this story at Slashdot.