本文通过对经手术证实的 7例青少年正常心脏感染性心内膜炎 (IE)经胸超声心动图表现进行分析，发现青少年正常心脏 IE赘生物的特异性高；位于瓣缘的赘生物易被识别，而位于腱索断端的较小赘生物易被漏判。对于青少年正常心脏突发瓣叶穿孔及 /或支持结构断裂者应综合考虑，高度警惕 IE。多普勒超声能准确判定 IE引起的瓣膜损伤程度，客观地反映病理生理改变。“,”This paper attempts to make an analysis of the echocardiogram display of the infectious endocarditis (IE) in 7 cases normal cardiac of juveniles.It is found that there is a high specificity of neoplasm in normal cardiac IE of juveniles.The neoplasm located on the valve edge is easy to be distinguished,but the smaller neoplasm located on broken end of chordae tendineae is difficult to be distinguished and may be omitted.It should be considered comprehensively for the proruption of the valve perforation in normal cardiac of juveniles and/or patient with supporting broken structure to keep high vigilant against IE.The Doppler supersound can determine precisely the valve damage caused by IE,and reflect the physiopathological changes objectively.