Towne W D, Patel R, Cruz J
Chest. 1978 Mar;73(3):417-9. doi: 10.1378/chest.73.3.417.
A 29-year-old woman with atrial fibrillation and severe rheumatic mitral regurgitation initially had a very loud third heart sound with high-frequency components (mitral knock), as well as with a first heart sound of widely varying intensity. After long diastoles a faint first heart sound was heard, with distinct separation from the third heart sound of the preceding cycle; however, on short cycles the loud and high-pitched third heart sound combined with a loud first heart sound to simulate the combination of a first heart sound with an ejection click. Phonoechocardiographic studies clarified the identity of the transients.
一名29岁患有心房颤动和严重风湿性二尖瓣反流的女性，最初有一个非常响亮且带有高频成分的第三心音（二尖瓣开瓣音），同时第一心音强度差异很大。在长舒张期后可听到微弱的第一心音，与前一心动周期的第三心音明显分开；然而，在短心动周期时，响亮且高调的第三心音与响亮的第一心音相结合，模拟出第一心音与喷射性喀喇音的组合。心音超声心动图研究明确了这些瞬态心音的特征。
