[Difficulties in differential diagnosis of the AL- and ATTR-cardiac amyloidosis. Case report].

The article presents a clinical case describing a complex differential diagnosis of cardiac amyloidosis types and verification of the diagnosis of AL-amyloidosis.

[Positron emission tomography in cardiological practice].

The utility of positron emission tomography in cardiology currently goes beyond the ischemic heart disease and covers an increasingly wider range of non-coronary pathology, which requires timely expert diagnostics, including chronic heart disease of any etiology, valvular and electrophysiology disorders, cardiooncology. Authors emphasize the importance of the development of positron emission tomography technologies in the Russian Federation. This includes the development and implementation of new radiopharmaceuticals for the diagnosis of pathological processes of the cardiovascular system, systemic and local inflammation, including atherosclerosis, impaired perfusion and myocardial metabolism, and also for solving specific diagnostic tasks in comorbid pathology.

[Myocardial scintigraphy with 99mTc-pyrophosphate in the diagnosis of cardiac amyloidosis: place in the diagnostic algorithm, features of the implementation and interpretation of the study].

The article summarizes the current experience of the nuclear medicine department of the Chazov National Medical Research Center of Cardiology in the implementation of myocardium scintigraphy with 99mTc-pyrophosphate with the differential diagnosis of the types of cardiac amyloidosis. Causes of false-positive, equivocal and non-diagnostic results, are analyzed. Possible ways to eliminate mistakes, including by modifying protocols of planar and tomographic research and optimizing the whole diagnostic algorithm for amyloidosis of the heart, are discussed.

[Practical guidelines for the diagnosis and treatment of transthyretin amyloid cardiomyopathy (ATTR-CM or transthyretin cardiac amyloidosis)].

This paper summarizes the data from updated international protocols and guidelines for diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM). The invasive and non-invasive diagnosis techniques and their combinations are briefly reviewed; the evidentiary foundations for each diagnostic option and tool are analyzed. The paper describes a customized algorithm for sequential diagnosis and differential diagnosis of patients with suspected ATTR-CM with allowance for the combination of clinical signs and diagnostic findings. Along with the awareness of primary care providers about the red flags of the disease and visualization criteria, as well as providing information to the patients about the possibility of performing therapy of ATTR amyloidosis and the risks of delayed diagnosis, the proposed algorithm enables timely patient routing and prescribing specific treatment.

[Nuclear medicine and molecular imaging in clinical practice: yesterday, today and tomorrow].

Over the past 40 years, nuclear medicine has grown to be the largest non-invasive diagnostic and therapeutic industry in the world, playing a pivotal role in various fields and disciplines of clinical practice and contributing to improved quality of life and patient prognosis. Over the first 20 years of the XXI century, the number of radionuclide procedures in the world has increased significantly, primarily due to innovations in radiopharmaceuticals, continuous improvement of the technical properties of equipment and the expansion of the boundaries of multimodal imaging. The review examines the historical and current trends in the development of nuclear medicine in the world and in Russia, including those related to radionuclide diagnostics, therapy and theranostics.

[Myocardial perfusion single-photon emission computer tomography and coronary angiography results in patients with different pretest probability of ischemic heart disease].

AIM: To study the relationship between pretest probability (PTP) of ischemic heart disease (IHD), calculated according to the recommendations of the European Society of Cardiology (ESC) of 2013 and 2019, with the perfusion of the left ventricle of the myocardium according to the single-photon emission tomography (SPECT) and the results of the invasive coronary angiography (CAG). MATERIAL AND METHODS: The study included 220 patients with a preliminary diagnosis of ischemic heart disease and planned invasive CAG. All patients underwent rest-stress perfusion myocardial SPECT within 1 month prior to or after CAG, standard quantitative parameters of left ventricular perfusion were assessed. Retrospectively clinical data was analyzed and PTP of IHD was assessed according to ESC recommendations for 2013 and 2019. RESULTS: Invasive CAG revealed obstructive lesion of one or more coromary arteries in 204 of the 220 patients (92.7%). In a retrospective analysis, taking into account gender, age and nature of the complaints, as recommended by ESC in 2013, PTP was rated as low (15%) in 13 patients (5.9%), as intermediate (1585%) in 207 patients (94.1%). Following the comprehensive survey (SPECT and CAG) 8 patients with low PTP (61.5%) underwent coronary revascularization. Among patients with intermediate PTP significant transient ischemia according to SPECT was detected in 31 (15.0%), initial at 107 (51.7%). According CAG among patients with intermediate PTP obstructive lesion was found in 192 (92.7%), 113 patients (58.8%) underwent revascularization. According to ESC recommendations of 2019, PTP was rated as low (15%) in 117 patients (53.2%), including 514% in 98 (44.5%). According to a survey (SPECT and CAG) 68 of them (58.1%) underwent revascularization. CONCLUSION: PTP measurements proposed by ESC can not be applied to patients of the Russian population with suspected ischemic heart disease without significant corrections. 2013 ESC recommendations with higher PTP values for all categories of patients reflect Russian population better, while 2019 recommendations mistakenly attribute patients to low PTP in at least 58% of cases. These results are preliminary and will be expanded in subsequent studies with more detailed analysis of PTP in included patients with suspected IHD.

[Current State and Future Technologies of Nuclear Imaging in Cardiology].

In this review, modern possibilities of nuclear imaging modalities in cardiology are considered. Perspectives of this branch of radiology are described according to the latest technological and methodological inventions and new clinical data.

[The diagnostic value of measuring the momentary blood flow reserve versus non-invasive methods to detect myocardial ischemia in assessing the functional significance of borderline coronary artery stenoses]. / Diagnosticheskaia tsennost' izmereniia momental'nogo rezerva krovotoka po sravneniiu s neinvazivnymi metodami vyiavleniia ishemii miokarda pri otsenke funktsional'noi znachimosti pogranichnykh stenozov koronarnykh arterii.

AIM: To estimate the diagnostic value of measuring the momentary blood flow reserve (MBFR) versus the surrogate non-invasive standard (SNS) for myocardial ischemia verification (MIV) (a combination of stress echocardiography and single-photon emission computed tomography). SUBJECTS AND METHODS: The investigation enrolled 50 patients with stable angina in the presence of chronic coronary heart disease (CHD) or suspected CHD, in whom coronary angiography (CA) revealed borderline coronary stenoses (50-70% lumen diameters). The examination algorithm had two options. In one option, when included in the study, patients had already CA results not older than 1 month, and MBFR was measured 4-7 days after non-invasive stress tests. In the other option, MBFR in the area of borderline coronary artery stenosis was measured simultaneously with CA; and the noninvasive stress tests were carried out in the following week. A total of 74 coronary stenoses were examined. RESULTS: SNS for MIV was positive in 14 (28%) patients. When comparing with the non-invasive methods of myocardial ischemia verification, the area under the ROC curve for MBFR was 0.961±0.019 (95% confidence interval, 0.888-0.992). The optimal cut-point was 0.92, which is corresponded by a sensitivity of 100% and a specificity of 84%. CONCLUSION: When compared with SNS for MIV, the method for measuring MBFR has a high diagnostic accuracy.

[Extraosseous abnormalities and artifacts in skeletal scintigraphy].

OBJECTIVE: to specify frequency, patterns and diagnostic significance of extraosseous soft tissue findings in 99mTc-pyrophosphate skeletal scintigraphy. MATERIAL AND METHODS: Results of skeletal scintigraphy from 1060 patients (447 men, 613 women) were analyzed. Scanning in "whole body" mode started in 3-4 hours after 740 MBq of radiotracer activity intravenous administration, and performed in anterior and posterior projections in continuous table motion mode at rate of 6-8 cm per minute. Single photon emission computed tomography/computed tomography (SPECT/CT) was additionally performed when necessary. RESULTS: Extraosseous scintigraphic findings were discovered in 161 (15.2%) patients, they can be divided into three categories: nephrourological (7.7%), soft tissue (5.4%) and artifacts (2.1%). First category included anatomical and functional changes in the urinary system (kidney location anomalies and nonobstructive uropathies). SPECT/CT was performed to differentiate calycostasis in the projection of the upper group of calyces and focal changes of the ribs. Soft tissue extrarenal findings included diffuse or focal RP hyperfixation within breasts (29 patients), thyroid glands (15), myocardium (5), scrotum (4) and abdominal cavity (4). Symmetrical increased RP accumulation in breast or thyroid lobes was accepted as normal. Pathologic soft tissue findings in 11 patients were verified by history or instrumental data: breast cancer (2), testicular cancer (1), nodular goiter (2), uterine fibroids (2), primary cancer with liver metastases (1), association of "hot kidney" phenomenon with chemotherapy (2), and "superscan" phenomenon with myelofibrosis (1). Causes of radiotracer artifacts in the liver and spleen (14) were of radiopharmaceutical factors, in axillary lymph node (7)--partially infiltrative radiopharmaceuticals administration, in the colon (1)--previous myocardial perfusion scintigraphy. CONCLUSION: Analysis and interpretation of abnormal extraosseous findings in skeletal scintigraphy is an essential component of additional diagnostic information, that can influence subsequent diagnostic and therapeutic tactics.

NEW APPROACH OF QUANTITATIVE NUCLEAR CARDIAC PERFUSION ASSESSMENT IN PATIENTS WITH PULMONARY HYPERTENSION.

Objective: to develop and implement a new processing approach of myocardial perfusion images obtained by single-photon emission computed tomography (SPECT) in patients with pulmonary hypertension (PH). Material and methods. 18 patients with idiopathic pulmonary hypertension underwent gated rest-stress perfusion SPECT with 99mTc-MIBI with CT-attenuation correction. Images were processed manually, with separate reorientation and semi-automatic contouring of both ventricles. MIBI intensity ratio in the right and left ventricles (RV/LV) was calculated using novel volumetric method, in comparison with other described approaches. Results. In patients with PH myocardial perfusion SPECT revealed abnormal RV visualization, dilation and reduced contractility, paradoxical motion and typical perfusion defects of interventricular septum. RV contouring in semi-automatic mode was possible in 100% of cases. The average values of RV/LV ratio in PH patients and normal group was 0.6097 ± 0.0090 and 0.2750 ± 0.0355, respectively (p<0.001). Conclusion. The new method of quantitative calculation of perfusion impairments allows to reveal the features of myocardial perfusion of the right and left ventricles in patients with pulmonary hypertension, with the potential to assess therapy effectiveness in these patients.> <0.001). Conclusion. The new method of quantitative calculation of perfusion impairments allows to reveal the features of myocardial perfusion of the right and left ventricles in patients with pulmonary hypertension, with the potential to assess therapy effectiveness in these patients.

[Phantom kidney at angionephroscintigraphy].

Based on the analysis of the data available in the literature and own clinical observations, the authors consider the diagnostic value of the little known scintigraphic phantom kidney phenomenon, a vascular pool that is detected at the angiographic stage of 99mTc-DTPA dynamic renal scintigraphy and that mimics a removed or absent kidney. The paper describes two cases of the phantom kidney. In one case, the phantom kidney detected on the side of nephrectomy manifested a kidney cancer recurrence in the bed of the removed organ; in the other, the kidney-like vascular pool in the patient with left-sided pelvic dystopic kidney was due to the recording of the intestinal vasculature at the site of the expected kidney location. Adherence to a number of methodical conditions for conducting a study, as well as combined single-photon emission computed tomography/computed tomography examination will be able to avoid interpretation errors and to ensure an adequate further diagnostic algorithm.

[New approaches to quantifying early disorders and perfusion inhomogeneity of the myocardium according to the data of single-photon emission computed tomography].

Objective: To develop novel quantitative approaches of myocardial perfusion analysis, to assess clinical usefulness of new parameters of initial myocardial perfusion impairments. Material and Methods: 80 patients selected from our database formed four groups: 20 patients with no cardiac disease suspect, no ischemic heart disease (IHD) risk factors and definitely normal myocardial perfusion (group 1), 40 patients with equivocal perfusion patterns, that are usually described visually as "inhomogeneous": 20 ­ with one subtle perfusion defect (group 2), 20 ­ with multiple ones (group 3), and 20 patients with non-severe but reliable defects, due to post-MI or another nontransmural cardiac event consequence. None of patients had current cardiac symptoms, positive stress-test results and/or single-photon emission computed tomography (SPECT) signs of stress-induced ischemia, so only rest images were analyzed. Perfusion maps were assessed quantitatively with Summed Rest Score (SRS) and Rest Extent (RE). Also new parameters ósev (severity sigma) и óhet (heterogeneity sigma) were used. They were calculated as mean-square deviations of relative perfusion values (in %) in each of 17 standard segments in reference to maximum of 100% (for ósev) and to arithmetical mean of those values (for óhet). To minimize known artifacts from CTACcorrected and noncorrected images, relative perfusion values for each segment were taken as maximal numbers of both images. Results: ósev in groups 1, 2, 3 and 4 was 15.9±2.6, 20.4±2.9, 22.4±3.4 and 26.0±3.9 (all paired p (s)<0.05, except p (group 2­3) = 0.19), óhet ­ 5.4±0.7, 9.1±1.6, 4.4±0.8, 11.3±2.1 (all paired p (s)<0.05 except p (group 1­3) = 0.11), respectively. Rest Extent in groups 1, 2, 3 and 4 was 4.1±1.7, 5.0±2.0, 4.7±2.3, 6.1±2.0 (all paired p (s)>0.05 except p (group 1­4) = 0.020); SRS ­ 1.3±0.6, 1.9±1.3, 1.6±1.4, 3.0±0.6 (all paired p (s)>0.05 except p (group 1­4)=0.013). Conclusion: Parameters ósev and óhet are suitable for quantitative description of myocardial perfusion "inhomogeneity", they are better than Extent/SRS in delineating normal/equivocal (inhomogeneous)/abnormal perfusion patterns.

[Adenosine triphosphate stress (99m)Tc-MIBI single-photon emission computed tomography in the diagnosis Miocardial Iscemia in patients with Microvascular Angina].

PURPOSE: To assess diagnostic potential of (99m)Tc-MIBI-single-photon emission computed tomography (SPECT) with intravenous adenosine triphosphate (ATP) infusion in comparison with exercise stress (EX) SPECT in patients with microvascular angina. MATERIAL AND METHODS: Patients with angina, positive exercise test and normal coronary angiogram (n=25) were included in the study. Patients underwent a three-phase (99m)Tc-MIBI-SPECT scan: at rest, exercise stress test and pharmacological stress with ATP infusion. Perfusion was graded on scale of 0-4. RESULTS: EX- and ATP-SPECT images showed mild reversible perfusion defects in 43 and 50%, moderate - in 19 and 12.5%, severe - in 5 and 16.7% of patients, respectively. CONCLUSION: Our results demonstrate that adenosine triphosphate stress (99m)Tc-MIBI-SPECT is comparable with exercise (99m)Tc-MIBI-SPECT in detection of ischemia and may be useful tool for diagnosing microvascular angina.

[An experience of the use of a curative method of cardiac shock wave therapy in patients with ischemic heart disease].

Aim of the study was to assess effects of cardiac shock wave therapy (CSWT) in patients with coronary artery disease (CAD) with refractory stable angina pectoris. Seventeen CAD patients with refractory II-IV class angina (3 women and 14 men, mean age 67.4+/-8.6 years) received the course of 9 procedures of CSWT. All patients had I-III New York Heart Association (NYHA) class congestive heart failure. Before and after CSWT medical examination with life quality assessment by means of the Minnesota Living Questionnaire, echocardiography, veloergometry, myocardial perfusion imaging with single-photon emission computed tomography (SPECT) using 99M-Tc-methyl-iodine-benzyl-guanydin (MIBG) and Holter ECG monitoring was performed. The dynamics of pro-angiogenic factors (VEGF, HGF, FGF-) were also measured by ELISA, and of brain natriuretic peptide (Nt-proBNP) by the electrochemoluminescence method. Most patients (80%) had significant life quality (<0.01) and myocardial perfusion improvement. Episodes of angina pectoris and nitrate intake were more than twice decreased. There was a significant increase in exercise tolerance (p<0.01). Holter ECG monitoring showed decreasing of an average heart rate (p<0.02); no worsening of previous cardiac arrhythmias was observed. The significant (p<0.05) decreases in plasma Nt-proBNP and increases in VEGF concentration were revealed after CSWT. CSWT procedures were well tolerated. The results of our study confirm high effectiveness and safety of CSWT in complex treatment of patients with CAD, resistant angina pectoris, including patients after myocardial revascularization and with heart failure.

[Adenosine triphosphate stress 99mTc-MIBI single-photon emission computed tomography in the diagnosis of ischemic heart disease].

This review is devoted to possibilities of single-photon emission computed tomography (SPECT) combined with pharmacological test with adenosine triphosphate (ATP) to detect myocardial ischemia in patients with ischemic heart disease (IHD). It contains consideration of contemporary problems and limitations inherent in use of pharmacological stress tests in radionuclide diagnostics; discussion of mechanisms of vasodilating effects of ATP in the context of modern concepts of purine receptors; detailed description of technique of pharmacological testing with ATP, as well as contraindications and possible side effects. Experience of foreign studies with the use of ATP stress testing for verification of presence of ischemia in patients with IHD is also presented.

[Diagnostic capabilities of single-photon emission computed tomography/computed tomography in the evaluation of perfusion disorders in pulmonary hypertension].

OBJECTIVE: to study the diagnostic capabilities of single-photon emission computed tomography/computed tomography (SPECT/ CT) in the evaluation of lung perfusion in pulmonary hypertension (PH). SUBJECT AND METHODS: Ten patients with pulmonary hypertension were examined. Its diagnosis was verified in accordance with the Russian guidelines for the diagnosis and treatment of PH, by conducting a set of studies involving right heart catheterization. CT angiopulmonography was carried out in all the patients. At the same time all the patients underwent a radiological study on a combined SPECT/CT scanner with the intravenous injection of the radiotracer 9mTc-MAA (technetium-99m-labelled macroaggregated albumin) with an activity of 2-4 mCi. RESULTS: CT-angiopulmonography revealed no thrombi in the pulmonary artery lumen in 7 patients and confirmed the diagnosis of pulmonary thromboembolism (PTE) at the level of segmental vessels in 3. SPECT/CT examination identified 5 cases of non-thromboembolic PH and 5 cases of PTE with consideration for SPECT perfusion defects and no visible lung tissue (fibrous or other) changes on a CT scan. It should be noted that the 5 patients diagnosed as having PTE included 2 patients in whom PTE had not previously been diagnosed at CT angiopulmonography. This may be due to that this technique cannot always clearly visualize thrombi in the pulmonary vessel lumen at a subsegmental level. CONCLUSION: The inivestigations have indicated that, by clearly ivisualizing pulmonary aanatomy, morphology, and function, combined SPECT/CT imaging is a valuable diagnostic tool in detecting lung pathology.

[Single-photon emission computed tomography in the diagnosis of myocardial perfusion abnormalities in patients with rheumatoid arthritis: preliminary data].

Increased cardiovascular morbidity and mortality in patients with rheumatoid arthritis (RA) may be attributed to the fact that a systemic inflammation existing in this disease may trigger the development of atherosclerosis. 99mTC-MIBI (4,2-methoxyisobutyl isonitrile) is a compound that permits myocardial perfusion to be visualized and has been proposed for the evaluation of the latter in patients with RA. Analysis of the results of the studies revealed transient myocardial ischemia areas in patients who did not take methotrexate while those who used it were found to have diminished perfusion areas that were, however, clinical insignificant.

[Perspectives of molecular visualization in cardiology].

The lecture concerns prospects of molecular visualization in cardiology. The term molecular visualization, its aims and problems are characterized Methods of molecular visualization involve such non-invasive techniques as ultrasonic investigation, optic visualization, MR tomography, x-ray CT radionuclide examinations (single photon emission computed tomography and positron-emission tomography). The scope of the above methods and their limits in visualization of biomarker target molecules in different pathological processes on the molecular level, cardiovascular diseases (CVD) are outlined. The discussion covers various methodological approaches to molecular visualization of the processes associated with development and progression of atherosclerosis, visualization of atherosclerotic plaques of a high risk underlying myocardial infarction or stroke, thrombosis, inflammation, apoptosis, cardiac failure; with myocardial regeneration after myocardial infarction, angiogenesis and other conditions as well as assessment of effect of novel target approaches to CVD treatment. For each of the processes (atherosclerosis, thrombosis, angiogenesis, apoptosis, gene expression and other pathological conditions) biomarker target molecules are considered. Optimal among them are molecular targets with established biological and clinical significance, target-receptors or enzymes, contrast substances, molecular probes tropic to biomarker molecular targets having adequate affinity and pharmacodynamics which allows molecular visualization in clinical setting. The investigators are faced with many unsolved problems which can be studied with methods of molecular visualization.

[Positron emission tomography in the diagnosis of atherosclerotic plaques in cancer patients].

AIM: To assess the capacities of radionuclide diagnosis of atherosclerotic changes in the great vessels in cancer patients. MATERIALS AND METHODS: 18F-fluorodeoxyglucose positron emission tomography (PET) was used to image unstable atherosclerotic plaques in the aorta and great vessels. Whole-body radiodiagnostic studies were retrospectively analyzed in 500 cancer patients of different ages and with different forms of neoplasms. RESULTS: Tomographic images showed atherosclerotic plaques in 21% of the patients with the verified diagnosis of coronary heart disease (CHD) and in 17% without its clinical manifestations. CONCLUSION: The study showed it possible to identify a cardiovascular risk in cancer patients.

[Tomographic methods in the assessment of myocardial perfusion].

Myocardium visualization using the most up-to-date tomographic techniques is extremely important in clinical cardiology. Myocardial viability assessment is of particular importance in management of patients with Ischemic Heart Disease (IHD). Although rest echocardiography is the most common in assessment of heart function, nuclear cardiology (SPECT and PET), and recently cardiac computed tomography and magnetic resonance become playing important clinical roles. Determining and understanding of real capabilities of these methods is of great necessity in this regard. This review examines the current abilities of current cardiac tomographic modalities for the assessment of myocardial perfusion in patients with known IHD.