1973 Volume 36 Issue 12 Pages 1313-1327
1) A new technique of kinetocardiogram (S-KCG) by using a straingauge was introduced to measure the absolute precordial movement. 2) The device had a constant frequency-response curve within the range lower than 15 Hz, linear relationship between the given displacement and the recorded amplitude and infinite time constant. 3) The influences of intervening soft tissue on the record could be avoided by the pressure (700 gram) on the chest wall applied through the pickup device. 4) The recorded tracings were consisted of 5 main components: atria wave ("a"), preejection wave and ejection wave (PE and E), midsystolic outward movement (MOM), recoil movement at the time of second heart sound (R), rapid and slow filling wave (rF and sF). A magnitude of a wave was expressed as "a" wave ratio to the total maximum deflection (a/TD). 5) Various changes in the configuration of S-KCG in altered hemodynamics which were induced by amyl nitrite inhalation, β-stimulant injection, arrhythmias and various congenital and acquired heart diseases were demonstrated. 6) Absolute amplitude of "a " wave as well as a/TD increased under the conditions of both pressure, and volume overload in the left atrium. In mitral stenosis, there was significant positive correlation between a/TD and the pulmonary capillary wedge pressure. 7) The direct measurement of isovolumetric contraction time could be possible by measuring the PE-E interval. 8) Several possible mechanism and genesis of MOM wave were discussed. 9) It was concluded that the S-KCG is useful in the evaluation of the synchrony of the contraction.
