title: The effect of heart rate and contractility on the measurement of left ventricular mass by 201Tl SPECT.
abstract: Left ventricular myocardial mass can be measured by 201Tl SPECT, but the effects of changes in heart rate and contractility have not been determined. We constructed a dynamic computer model simulating the contracting left ventricle. Thirty two summed static views at each of 3 heart rates and 3 ejection fractions were manufactured to simulate a 180 degrees acquisition. Each image set underwent tomographic reconstruction. Left ventricular mass was measured at a fixed percent threshold in each slice. The results show that left ventricular mass varied little with heart rate (4%) and only slightly more (8%) with ejection fraction. Thus, in the normal clinical setting, left ventricular mass measurements by SPECT are minimally affected by the dynamic state of the heart.
mesh_terms: D003198:Computer Simulation; D006321:Heart / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D006339:Heart Rate; D009200:Myocardial Contraction; D013794:Thallium Radioisotopes; D014055:Tomography, Emission-Computed
chemical_list: D013794:Thallium Radioisotopes