Evaluation of myocardial viability by different non-invasive cardiovascular imaging modalities

Abstract

Introduction. Evaluation of myocardial viability allows to determine the likelihood of reversibility of myocardial function after revascularization (1-3), as confirmed by the European Society of Cardiology Guidelines on Myocardial Revascularization in 2018 (4). Myocardial viability can be determined by different non-invasive methods, and the selection of the most appropriate one can become a challenge (5-7), so this study aims to compare the different non-invasive radiological methods. Research aim. Compare different non-invasive radiological methods (single photon emission computed tomography (SPECT), positron emission tomography/computed tomography (PET/CT), cardiac magnetic resonance imaging (CMR)) by assessing myocardial viability. Research methods and organization. A prospective study involving 30 patients examined and treated at the Hospital of Lithuanian University of Health Sciences Kaunas Klinikos Department of Cardiology in 2016-2018 was conducted. The main inclusion criteria were myocardial infarction, followed by a marked decrease in left ventricular ejection fraction (LVEF <40%), and severe coronary artery lesions, which benefit of revascularization being questionable due to formed scar lesions in the myocardium. Patients were selected with reference to the clinical diagnosis (coronary artery disease (CAD), heart failure (HF)) and examined by different non-invasive radiological examinations (echocardiography, SPECT, PET/CT and CMR) over a few days to assess myocardial viability. In order to assess objectively, the heart segments were numbered consecutively from the top to the basal part in ascending order (1- 16). During echocardiography, myocardial viability was assessed by its motility, using SPECT and PET methods myocardial segments were assessed as non-viable if less than 50% radioactive material (99mTc-MIBI) or glucose analogue (18F-FDG) were accumulated. CMR verified myocardium to be completely no