Dynamic Single-Photon Emission Computed Tomography Data Analysis: Capabilities for Determining Functional Significance of Coronary Artery Atherosclerosis

The aim of the study was to develop the method for collecting and processing scintigraphic data to determine myocardial flow reserve by using gamma-camera with a new type detector based on Cadmium Zinc Telluride (CZT). Sixteen coronary artery disease patients and nine healthy volunteers received cardiac dynamic single-photon emission computed tomography with technetium 99m methoxyisobutylisonitrile ({99m}Tc-MIBI) at rest and during pharmacologic stress test. Data processing involved a formation of regions of interest from the left ventricular (LV) cavity and myocardial walls to build activity-time curves. Myocardial flow reserve index was determined as a quotient of two ratios of mean myocardial counts to area under a curve peak from LV cavity during stress test and at rest. Mean values of myocardial flow reserve index were 1.86 (1.59; 2.2) in group of healthy volunteers and 1.39 (1.12; 1.69) in patients with multivessel coronary artery disease. When the value of this index was less than 1.77, the method allowed for identification of multivessel disease with sensitivity and specificity of 81.8% and 66.7%, respectively. Standard myocardial perfusion scintigraphy in combination with the method of myocardial flow reserve index determination allows for increasing diagnostic significance of the scintigraphic approach for assessment of coronary microcirculation lesions in multivessel coronary artery disease

Lung scintigraphy in differential diagnosis of peripheral lung cancer and community-acquired pneumonia

Ventilation/perfusion lung scintigraphy was performed in 39 patients with verified diagnosis of community-acquired pneumonia (CAP) and in 14 patients with peripheral lung cancer. Ventilation/perfusion ratio, apical-basal gradients of ventilation (U/L(V)) and lung perfusion (U/L(P)), and alveolar capillary permeability of radionuclide aerosol were determined based on scintigraphy data. The study demonstrated that main signs of CAP were increases in ventilation/perfusion ratio, perfusion and ventilation gradient on a side of the diseased lung, and two-side increase in alveolar capillary permeability rate for radionuclide aerosol. Unlike this, scintigraphic signs of peripheral lung cancer comprise an increase in ventilation/perfusion ratio over 1.0 on a side of the diseased lung with its simultaneous decrease on a contralateral side, normal values of perfusion and ventilation gradients of both lungs, and delayed alveolar capillary clearance in the diseased lung compared with the intact lung

The development of Lviv hotel business in the interwar period (1919–1939)

The current paper researches and analyses the start and development of the hotel business in Lviv of the interwar period. The main focus is set on the division of accommodation establishments into categories, their structure and location. Much attention is also paid to the description of hotels and their pricing policy depending on their status and venue. Numerous tables help to structure the statistical data, especially their client capacity, number of rooms, location etc

Иван Леонидов и стиль «Наркомтяжпром»

The article considers stylistic peculiarities of the Narkomtyazhprom (NKTP) project and several contemporary projects by I. I. Leonidov, which form a specific style combining futuristic and ancient Egyptian motives. Taking into account the impact made by this style on the works by the group of Ginzburg and the Vesnin brothers and the NKTP bureaus headed by them, the author of the article proposes to consider the style as a significant phenomenon in Soviet architecture of the middle 1930s and to introduce the term “NKTP Style”.В статье рассматриваются стилистические особенности проекта НКТП и ряда современных ему проектов И. И. Леонидова, складывающиеся в специфическую стилистику, сочетающую футуристические и древнеегипетские мотивы. С учетом факта влияния этой стилистики на работы группы Гинзбурга – Весниных и руководимых ими мастерских НКТП предлагается осознать ее как крупное явление в советской архитектуре середины 1930-х годов и вести термин «Стиль НКТП»

Современные сцинтиграфические методы оценки миокардиального кровотока и резерва

 Background. Today, myocardial perfusion scintigraphy is an informative and accessible method for evaluating ischemic changes in the heart. However, this method has limitations, which are more connected with a semiquantitative assessment of the study results. Currently, there is a class of specialized gamma cameras with detectors based on cadmium-zinc-telluride, which allow quantitative analysis of scintigraphic data on coronary hemodynamics, i.e. evaluate indicators of coronary blood flow and reserve.The aim of the review was to present and summarize the information about the coronary circulation within physiological and pathological conditions, as well as the possibilities of modern radionuclide methods in assessing coronary blood flow and reserve.Materials and methods. In the process of preparing the review article, “PubMed”, “Web of Science”, “ScienceDirect” and “Elibrary” scientific databases were used. Search requests included keywords such as: coronary artery disease, myocardial blood flow, coronary (myocardial) flow reserve, single-photon emission computed tomography, cadmium-zinc-telluride, positron emission tomography.Results. The review includes information on the state and methods of regulating coronary hemodynamics under normal conditions and against the background of pathological changes. It also includes information about radionuclide methods for assessing coronary hemodynamics, which are of  historical importance, currently used and promising, as well as dynamic single-photon emission computed tomography.Conclusion. The potential of dynamic single-photon emission computed tomography as a method for quantification of coronary blood flow and reserve is high. This technique can become a simple and affordable alternative to the existing methods for assessing coronary (myocardial) blood flow and reserve. This will increase the information content of radionuclide diagnostics in assessing the severity of coronary insufficiency for more accurate risk stratification and determination of appropriate treatment tactics for cardiac patients.  Введение. Перфузионная сцинтиграфия миокарда на сегодняшний день является информативным и доступными методом оценки ишемических изменений сердца. Однако эта методика, как и любая другая, имеет ряд определенных ограничений, которые в большей степени связаны с полуколичественной оценкой результатов исследования. В настоящее время существует класс специализированных  гамма-камер с детекторами на основе кадмий-цинк- теллура, позволяющих проводить количественный анализ  сцинтиграфических данных о состоянии коронарной  гемодинамики, т.е. оценивать показатели коронарного  кровотока и резерва.Цель обзора – представить и обобщить сведения о  физиологии кровообращения сердца в норме и при патологии, а также возможностях современных  радионуклидных методов в оценке коронарного кровотока и резерва.Материалы и методы. В процессе подготовки обзорной статьи использовались научные базы данных PubMed, Web of Science, ScienceDirect, Elibrary. Поисковый запросы  включали ключевые слова: coronary artery disease,  myocardial blood flow, coronary (myocardial) flow reserve,  single-photon emission computed tomography, cadmium-zinc- telluride, positron emission tomography, ишемическая  болезнь сердца, миокардиальный кровоток, однофотонная эмиссионная компьютерная томография, позитронная эмиссионная томография, резерв коронарного (миокардиального) кровотока.Результаты. Обзор включает в себя сведения о состоянии и способах регуляции коронарной гемодинамики в условиях нормы и на фоне патологических изменений, радионуклидных методах оценки состояния коронарного русла, имеющих историческое значение, использующихся в настоящее время и перспективных, в том числе динамической однофотонной эмиссионной компьютерной томографии.Заключение. Потенциальные возможности динамической однофотонной эмиссионной компьютерной томографии как метода количественной оценки коронарного кровотока и резерва высоки. Эта методика может стать простой и доступной альтернативой существующим способам оценки коронарного (миокардиального) кровотока и резерва, что позволит повысить информативность радионуклидной диагностики в оценке тяжести коронарной недостаточности, а значит будет способствовать более точной стратификации риска и определению походящей тактики лечения  кардиологических пациентов.

RADIONUCLIDE EVALUATION OF CONTRACTILITY OF THE RIGHT HEART IN MITRAL VALVE STENOSIS

Aim. With the use of radionuclide weight-adjusted tomoventriculography (RTVG), to assess the condition of the right heart chambers in mitral valve stenosis (MV) of rheumatic origin.Material and methods. Totally, 20 patients studied (mean age — 54,2±8,22 y.) with rheumatic mitral valve lesion, of those 13 were investigated before and after correction of the defect. All patients, before and after correction of the defect were examined with the RTVG.Results. In all patients with the MV defect, we found a decrease of regional contractility of the RV. Patients with MV defects, related to the comparison group, had significantly more statistically decreased EF, MCI and SSN/Z, EF and higher values of EDV of the RV. Valve defect correction led to statistically more significant decrease of ESV, increase of MCI and EF RV. The sizes of the right atrium, measured with RTVG, were significantly higher comparing to the controls, and after correction of the defect, they reduced.Conclusion. The RTVG method could be applied for non-invasive assessment of the right heart chambers function in patients with MV stenosis of rheumatic origin

Left atrial volume index and non-ischemic myocardial contrast pattern as a predictor of continued left ventricular remodeling in patients with ischemic cardiomyopathy: magnetic resonance imaging data

Aim. To evaluate the heart morphological features and the significance of the non-ischemic myocardial contrast pattern in medium-term prognosis of continued left ventricular (LV) remodeling after surgery in patients with ischemic cardiomyopathy.Material and methods. The results of paramagnetic contrast-enhanced cardiac magnetic resonance imaging (MRI) were analyzed in 31 patients with ischemic cardiomyopathy with an average age of 58,4±7,6 years before complex surgical treatment. The heart morphological features and non-ischemic contrast pattern in the myocardial segments remote from the infarction area according to contrast-enhanced MRI were assessed.Results. Patients with a non-ischemic contrast pattern had higher left atrial volume index (p=0,02), LV end-systolic index (p=0,03), and right ventricular sizes (p=0,01). A relationship was found between the left atrial volume index and cardiac remodeling in the postoperative period (p<0,005, correlation coefficient r=0,53).Conclusion. Non-ischemic myocardial contrast pattern is accompanied by an increase in the left atrial volume, which in turn is a predictor of continued LV remodeling in patients with ischemic cardiomyopathy in the postoperative period

Combined myocardial perfusion scintigraphy and computed tomography: diagnostic and prognostic value in coronary artery disease

Modern imaging techniques occupy an important place in the diagnosis, selection of treatment and prognosis of patients with coronary artery disease. Hybrid imaging is a combination of two sets of diagnostic data that complement and enhance each other by comparing anatomical and functional characteristics. As a rule, hybrid imaging is synergistic, that is, more powerful, since the addition of new information leads to an increase in the sensitivity and specificity of each of the modalities separately.The review provides brief information on the diagnostic efficacy of myocardial perfusion scintigraphy (MPS), computerized tomography (CT) coronary angiography in comparison with invasive coronary angiography with fractional flow reserve. The diagnostic and prognostic significance of assessing calcium index with MPS, as well as CT coronary angiography combined with MPS in the diagnosis, risk stratification and prognosis of patients with coronary artery disease, is characterized in detail. A separate section is devoted to the importance of hybrid imaging in making decisions about myocardial revascularization

Radionuclide imaging methods in the diagnosis of microvascular dysfunction in non-obstructive coronary artery disease

Non-obstructive coronary artery disease is generally considered as a favorable type of pathology, however, a number of studies indicate that in non-obstructive atherosclerosis, the risk of such cardiovascular events as myocardial infarction, ischemic stroke, sudden cardiac death and decompensated heart failure cannot be completely ruled out. This may be due to microvascular dysfunction. However, due to the small diameter of vessels, none of the imaging techniques used in clinical practice makes it possible to assess microvascular morphology. To date, the most well-established methods for assessing myocardial perfusion are single-photon emission computed tomography (SPECT) and positron emission tomography (PET). The ability to quantify myocardial blood flow and coronary flow reserve allows SPECT and PET to be the methods of choice for non-invasive diagnosis of microvascular dysfunction. This review is devoted to current data on the clinical significance of radionuclide diagnosis of microvascular dysfunction in patients with non-obstructive coronary artery disease

Relationship between the degree of myocardial damage according to contrast-enhanced cardiac magnetic resonance imaging and laboratory data in patients with acute myocardial infarction

Aim. To evaluate the information value of a complex of clinical and biochemical parameters of myocardial damage in predicting the development of transmural myocardial damage according to magnetic resonance imaging (MRI) in patients with acute myocardial infarction (AMI).Material and methods. The study included patients admitted to the emergency cardiology department with acute coronary syndrome. All patients underwent invasive coronary angiography, laboratory tests, and dynamic determination of cardiac biomarkers. In the interval of 6,1±4 days from admission to the hospital, patients underwent contrast-enhanced cardiac MRI. According to the pattern of delayed contrast enhancement, patients were divided into two groups: with a transmural and subendocardial pattern.Results. The mean age of patients was 62,5±10,5 years, while 27 (71,1%) had ST-segment elevation AMI. Among the risk factors for coronary artery disease, dyslipidemia (89,5%), hypertension (68,4%), and smoking (57,9%) were the most common. Creatine phosphokinase-MB (CPK-MB), serum high-sensitivity cardiac troponin I (cTnI) and C-reactive protein (CRP) values after 24 h were significantly higher in patients with transmural hyperenhancement. Moderate positive relationship was found between the global size of left ventricular (LV) damage according to MRI data and the levels of CPK-MB after 24 h and 4 days, as well as with CRP after 24 h, 4 and 7 days, and cTnI level after 24 h and 4 days. In the group of patients with transmural pattern, the global size of LV damage was significantly higher. Patients of this group were characterized by higher prevalence of microvascular obstruction. In a univariate regression analysis, there were following significant predictors of transmural myocardial damage: CPK-MB after 4 days (p=0,023) and ST segment elevation (p=0,029). Multivariate regression analysis showed that the only independent predictor of transmural myocardial damage was an increase in CPKMB after 4 days (p=0,023).Conclusion. An independent predictor of LV transmural damage in AMI was an elevated level of CPK-MB after 4 days. However, this laboratory marker had unsatisfactory information completeness and predictive quality. In this regard, cardiac MRI in patients with AMI, compared with the standard clinical assessment, can be considered preferable for assessing the depth of myocardial damage, risk stratification, and prognosis