Peak rate of left-ventricular ejection by a gated radionuclide technique: correlation with contrast angiography.

Gated radionuclide cardiac blood-pool imaging can produce reliable estimates of left-ventricular (LV) volume and ejection fraction. The ventricular volume curve can be used to develop normalized ejection rates, since count volumes and framing times are known. To test the accuracy of the peak ejection rate (maximum dv/dt), as derived by a standard computer algorithm, we studied 15 patients with coronary artery disease by both contrast ventriculography and radionuclide angiography. Max dv/dt by the radionuclide technique correlated well with the angiographic result: r = 0.92, p less than 0.01. The mean intraobserver variation was (plus or minus 12%) and the mean interobserver variation plus or minus 0.33 end-diastolic volumes per sec (plus or minus 13%). We conclude that maximum dv/dt may be derived from gated blood images, with reasonable accuracy and modest variability.