An attempt to evaluate pulmonary hypertension by phase analysis of radionuclide ventriculography

Using phase analysis derived from the gated blood pool imaging, the pattern of right ventricular regional contraction was examined in 5 patients with pulmonary hypertension who showed 30 mmHg of pulmonary arterial systolic pressure and 20 mmHg or more of mean pulmonary arterial pressure. All of the patients had markedly delayed phase in contraction of right ventricular outflow tract. Pulmonary arterial pressure positively correlated with both the proportion of delayed phase area to the whole right ventricle and mean phase difference between the right and left ventricles. The results suggest the usefulness of phase analysis in the non-invasive evaluation of incease in overloading of right ventricular pressure. (Namekawa, K)