EFFECT OF MYOCARDIAL PERFUSION ABNORMALITIES MEASURED BY SPECT ON LEFT VENTRICULAR FUNCTION

摘要

The aim of the study was to investigate the relationship between myocardial perfusion abnormalities and the left ventricular ejection fraction (LVEF). One hundred and sixty-five patients aged 31-73 years were studied. The patients were investigated with myocardial perfusion single photon emission computed tomography (SPECT) at rest and during stress using ~(99)Tc~m-MIBI (methoxyisobutyl isonitrile), as well as a gated blood pool study in resting conditions. After reconstruction of the SPECT perfusion data, a polar map of the left ventricle (LV) perfusion distribution was created with arbitrarily marked anteroseptal, posterolateral and inferior wall regions. The extent of perfusion defect was expressed as a percentage of the total LV area, separately for rest (fixed defect) and stress (total defect) studies. The value of the reversible defect was calculated as the difference between the total defect and the fixed defect. The patients were divided into three groups according to the results of the perfusion scintigraphy: the first group (G1) comprised 20 patients with perfusion parameters within normal range, both at rest and during stress; G2 included 12 patients with perfusion defects during stress only and G3 included 133 patients with perfusion abnormalities at rest. In the quantitative evaluation of the rest study, the numerical values of myocardial perfusion in Gl and G2 were within the range of normal values. On the other hand, in G3 these values exceeded markedly the normal values and were significantly greater than in Gl or G2. All the groups differed significantly in the total and reversible defect categories. In Gl and G2, no correlations between the numerical indices of the myocardial perfusion distribution and the LVEF were detected. In G3, with more advanced myocardial perfusion pathology, the correlation was highly significant in the categories of fixed and total defects, while no statistically significant correlation in the reversible defect category was found. In the correlation analysis between regional perfusion defects and the LVEF in G3, the highest values were observed in the anteroseptal wall of the LV.