Assessment of perfusion and diastolic function in patients with early-stage microvascular dysfunction and arterial hypertension according to 99mTc-SPECT/CT imaging

Abstract

Objective: to study the correlation between quantitative perfusion parameters and the diastolic function in patients with microvascular dysfunction and arterial hypertension, stage 1, pain in the left half of the chest and intact coronary arteries (ICA), according to the single-photon emission computed tomography with 99mTc. Material and methods. The study included 29 patients with stage I arterial hypertension confirmed by 24-hour blood pressure monitoring, without left ventricular hypertrophy, with pain in the left half of the chest and ICA, each of whom underwent diagnostic invasive coronary angiography and SPECT/CT of the myocardium with 99mTc-technetrile at rest and in combination with stress. Results. In the examined patients with stage I arterial hypertension, without left ventricular hypertrophy with pain in the left half of the chest and ICA, according to S-SPECT/CT, disturbances in diastolic function (DF) of the LV, heterogeneity of perfusion at rest and stress-induced myocardial ischemia, corresponding to the initial manifestations of coronary insufficiency, were revealed, caused by a decrease in the perfusion reserve due to secondary microvascular dysfunction (vMSD), and is, apparently, the main factor in the occurrence of pain in the left half of the chest in this category of patients. A reliable inverse relationship has been established between speed and direct time indicators of LV DF and the prevalence and severity of stress-induced myocardial ischemia. Conclusion. In patients with stage I arterial hypertension, without left ventricular hypertrophy with pain in the left half of the chest and ICA perfusion deficiency and myocardial ischemia are associated with a significant increase in diastolic duration and a decrease in the velocity parameters of LV DF, which is revealed by SPECT/CT data already in the early stages and initial stage of the HD disease. The occurrence of left-sided heart failure in patients with hypertension and ICA is associated with coronary insufficiency caused by vMSD.