Quantitative Spect Measurement of the Tissue Blood Flow in Myocardium by the Absolute Uptake of Radiopharmaceutical 99m TC -Technetril

Background. Quantitative calculation of tissue blood flow by means of radionuclide emission tomography is of great importance in studies of myocardial blood supply. Quantifying blood flow with PET requires a medical cyclotron. 99mTc-Technetrile is a unique radiopharmaceutical (rfp) with a high and approximately the same extraction fraction by the myocardium and other tissues — chemical microspheres.Objective. Development of a technique for calculating tissue blood flow for a quantitative assessment of the blood supply to the heart muscle, according to the determination of tissue absorption of 99mTc-Technetrile during CardioSPECT.Design and methods. The distribution of rfp — chemical microspheres 99mTc-Technetrile in the body is proportional to blood flow. Determining the amount of accumulation of rfp in different regions can be performed using SPECT. Weused data of 14 patients with myocardial infarction, who underwent SPECT with 99mTc-Technetrile, with the calculation of tissue blood flow.Results. Evaluation of rMBF at rest in the area of unaffected myocardium revealed rMBF = 65±7 ml/min/100 g, in segments with the presence of viable myocardium according to the ultrasound test with dipyridamole rMBF = 53±7 ml/min/100 g, in postinfarction regions of the transmural damage to the left ventricular wall without viable myocardium rMBF = 27±8 ml/min/100 g.Conclusion. The calculation of tissue blood flow via CardioSPECT is useful for pathophysiological assessment of the blood supply to the heart muscle.