Answer: A. endocarditis
Explanation:
Endocarditis is the inflammatory process of the endocardium, especially that located in the heart valves. There are several factors causing endocarditis, the most frequent and lethal being endocarditis caused by infectious agents. The most common mechanism is endothelial injury due to blood flow turbulence, be the one generated by a defective valve (rheumatic, bicuspid aortic valve, dysfunctional valve prosthesis), or by any congenital anomaly that causes flow turbulence (interventricular communication, obstructive hypertrophic cardiomyopathy, aortic coarctation).
The most common site of injury, and therefore the most frequent site of vegetation formation, is at the closing line of a valve, usually on the atrial surface of the atrioventricular valves or on the ventricular surface of the ventriculoarterial valves. With the endothelial lesion occurs the formation of a sterile thrombus, which can be colonized by bacteria that multiply there, turning the thrombus into vegetation. These vegetations are avascularized, making the treatment of endocarditis difficult due to the low access of antibiotics to microorganisms.
