发病机理原发病变是心内膜下纤维蛋白血栓。在心内膜下病变形成后,发生于血流高速处、高压腔至低压腔处、以及侧压较低的区域,例如二尖瓣返流的心房侧或主动脉瓣关闭不全的心室侧,室间隔缺损则发生在右心室侧。其次,还要有菌血症,如无菌血症,即无感染。葡萄球菌菌血症,约65％可发生细菌性心内膜炎,肺炎双球菌感染伴脑膜炎,则仅33％发生细菌性心内膜炎,发病率与细菌的致病力有关。除细菌因素外,免疫学也有改变,50％ Pathogenesis The primary lesion is endocardial fibrin thrombus. After the formation of subendocardial lesions, occurs at high velocity, high pressure chamber to the low pressure chamber, and low lateral pressure area, such as mitral regurgitation of the atrium or aortic valve insufficiency of the ventricular side of the room Septal defect occurs in the right ventricular side. Second, there must be bacteremia, such as bacteremia, that is, no infection. Staphylococcus aureus, about 65% of bacterial endocarditis can occur, pneumococcal infection with meningitis, only 33% of bacterial endocarditis occurs, the incidence of bacterial pathogenicity. In addition to bacterial factors, immunology has changed, 50%