Application of Perfussion Severity Index and Perfusion Heterogeneity Index for Evaluating Pet Studies With Rubidium-82

Abstract

Coronary artery disease (CAD) is one of the most common causes of mortality both in Russia and worldwide, which necessitates the development of diagnostic methods for detecting and localizing pathology in coronary vessels at the earliest stages. Among the non-invasive diagnostic methods, one of the most common and effective is myocardial perfusion imaging using single-photon emission computed tomography (SPECT), which, however, only allows for semi-quantitative assessment. Quantitative assessment is possible using positron emission tomography combined with computed tomography (PET/CT), including the use of 82Rb-chloride as a tracer. The aim of this study was to evaluate the feasibility of applying the SPECT technique proposed by Ansheles et al. in 2015, for the detection of early perfusion abnormalities, analyze the results obtained, and determine the differences in the use of the 15-segment and 17-segment myocardial division schemes in PET with rubidium-82 chloride. Materials and methods: PET studies with rubidium-82 chloride were conducted on 10 patients with symptoms of CAD but without coronary artery stenosis according to coronary angiography. Perfusion severity indices and perfusion heterogeneity indices were calculated for each patient using both the standard 17-segment model and the previously proposed 15-segment model. Results: Statistically significant differences between the 17-segment and 15-segment models were only observed when assessing the heterogeneity index at rest; in other cases, no statistically significant differences were found between the two models, indicating the possibility of using the 15-segment model for calculating quantitative parameters. Both models showed a lack of correlation between perfusion severity indices during rest and stress studies, which may allow for the use of this index in evaluating the presence of microvascular abnormalities. No statistically significant differences were found between men and women in the analysis of these indices...