NONINVASIVE ESTIMATION OF LEFT-VENTRICULAR MAX(DP DT) FROM AORTIC FLOW ACCELERATION AND PULSE-WAVE VELOCITY

The Doppler method of obtaining left ventricular Max(dP/dt) proposed r ecently was based on the measurement of mitral regurgitation velocity. Since Max(dP/dt) is an isovolumic phase index, its use in cases of mi tral regurgitation may be open to argument. However, we had proposed a noninvasive method of estimating left ventricular Max(dP/dt) based on different principles. In our method, Max(dP/dt) had been given by Max (dP/dt) = rhocMax(du/dt), where rho is the blood density, c is the pul se wave velocity, and u is the flow velocity in the aorta. We had deri ved the above equation theoretically, and confirmed its validity by an imal experiments. In our previous study, we also applied our method in the clinical setting. The aortic flow velocity was measured by Dopple r echocardiography, and the pulse wave velocity by mechanocardiography or Doppler echocardiography. rhocMax(du/dt) obtained noninvasively wa s compared with Max(dP/dt) measured with a catheter-tip micromanometer . We found an excellent correlation between rhocMax(du/dt) and Max(dP/ dt), and concluded that rhocMax(du/dt) is useful in assessing noninvas ively the contractile state of the left ventricle. Here, we summarize our method, review previous results, and report new results of the cli nical application of our method.