Initial low frequency vibrations of the first heart sound.
نویسندگان
چکیده
منابع مشابه
The initial vibrations of the first heart sound.
The major component of the normal first heart sound is that due to valvular closure. Preceding this there occur low frequency, low amplitude vibrations commonly attributed to auricular systole. It has been shown in this study that such vibrations appear invariably even though the auricles are fibrillating, and in heart block when auricular systole is widely seperated from ventricular systole. I...
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The initial low frequency component of the first heart sound, 'M', has been studied in normal subjects, and in patients with vario-s prosthetic mitral valves and with mitral stenosis, using simultaneous low frequency phonocardiography, echocardiography, and apex cardiography. The techniques showed 'M' to have a constant morphology in preisovolumic systole. In mitral stenosis, 'M' and the preiso...
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A method for taking tracings which represent actual movements of the precordium (displacement curves) or records which show waves proportional to the velocity of movement of the chest wall (velocity curves) is described. The equipment employed is readily available, and the method is easy to use. The displacement curves are nearly identical with cardiograms taken with a good optical setup, and t...
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ژورنال
عنوان ژورنال: Heart
سال: 1973
ISSN: 1355-6037
DOI: 10.1136/hrt.35.7.691