BackgroundIschemic heart disease (IHD) has the highest mortality rate in the globe. This returns to the poor diagnostic and therapeutic strategies including the early prevention methods.AimsTo assess the changes in the single channel electrocardiography (SCECG) at rest and on exercise test in patients with vs without IHD confirmed by stress computed tomography myocardial perfusion (CTP) imaging with vasodilatation stress-test.ObjectivesIHD frequently have preventable risk factors and causes that lead to the disease appearance. However, the lack of the proper diagnostic and prevention tools remains a global challenge in or era despite the current scientific advances.Material and methodsA single center observational study included 80 participants from Moscow. The participants aged ≥ 40 years and given a written consent to participate in the study. Both groups, G1=31 with vs G2=49 without post stress induced myocardial perfusion defect, passed cardiologist consultation, anthropometric measurements, blood pressure and pulse rate, echocardiography, cardio-ankle vascular index, performing bicycle ergometry, recording 3-minutes SCECG (using CARDO-QVARK) before and just after bicycle ergometry, and then performing CTP. The LASSO regression with nested cross-validation was used to find association between CARDO-QVARK parameters and the existence of the perfusion defect. Statistical processing carried out using the R programming language v4.2, Python v.3.10 [^R], and Statistica 12 programme.ResultsThe CARDO-QVARK parameters analysis have a specificity 75.5 % [95 % confidence interval (CI); 0.628; 0.88], sensitivity 51.6 % [95 % CI; 0.333; 0.695], area under the curve (AUC) 67 % [95 % CI; 0.530; 0.801] in compare to bicycle ergometry AUC; 50.7 % [95 % CI; 0.388; 0.625], specificity 53.1 % [95 % CI; 0.392; 0.673], sensitivity 48.4 % [95 % CI; 0.306; 0.657], based on our study results.ConclusionThe SCECG have no statistically significant higher diagnostic accuracy in compare to bicycle ergometry. However, CARDO-QVARK has the potential to improve the diagnostic accuracy of the bicycle ergometry.OtherFurther investigations required to uncover the hidden capabilities of CARDO-QVARK in the diagnosis of ischemic heart disease.