Multiharmonic analysis of the left ventricular function

To assess left ventricular function regionally the global and 9 sectorial time-activity curves were noise-filtered by approximation up to the 4th harmonic and analyzed in terms of the following parameters: preejection period, time to/and peak ejection and filling rates, ejection fraction, and phase of the first harmonic. Each sectorial parameter was computed as the difference between exercise and rest quantitated the exercise response of the respective parameter. The standard values of all parameters were evaluated in 33 normals. These were compared with the results of 21 patients with isolated critical LAD stenosis. The use of all parameters of the regional left ventricular time-activity curve increases the sensitivity of equilibrium radionuclide ventriculography decisively, while specificity remains unchanged. (Author)