[Infective endocarditis. Epidemiology, pathophysiology and histopathology].

The annual incidence of infective endocarditis is estimated around 30 cases per million inhabitants in population-based studies performed in western countries. The incidence of infective endocarditis is markedly increased in patients with prosthetic heart valves and, particularly, in patients with prior infective endocarditis. The epidemiology of infective endocarditis has changed ; it occurs now in older patients and Staphylococcus has become the most frequent responsible microorganism. The pathophysiology of infective endocarditis results of complex interactions between circulating microorganisms, diseased valvular endothelium, and host defences. The main lesions of IE are vegetations which cause emboli and destruction of valvular and/or perivalvular tissues leasing to acute valvular regurgitations.