[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.

Possibilities of Evaluating the Dynamics of Left Ventricular Perfusion and Contractility in Patients with Chronic Heart Failure after Implantation of a Heart Contractility Modulator Using Perfusion Single-Photon Emission Computed Tomography

Perfusion scintigraphy and single-photon emission tomography of the myocardium are promising methods for complex assessment of the state of the left ventricle myocardium in patients with chronic heart failure. These methods of nuclear cardiology can be performed in patients with reduced renal function, as well as the presence of implanted devices such as implantable cardioverters-defibrillators, resynchronizing devices and cardiac modulating therapy, which is their undeniable advantage. The reproducibility of the method is ensured bu fully automated calculation of parameters of myocardial perfusion and contractility. To date, there are no data in the literature on the use of nuclear cardiology methods as an imaging technique in patients with cardiac contractility modulation devises. This paper describes the current possibilities and prospects of nuclear medicine methods in patients with chronic heart failure after implantation of a heart contractility modulator.

Relationship of obesity, low-density lipoprotein cholesterol and myocardial perfusion in patients with risk factors and without atherosclerotic cardiovascular diseases

Aim. In the retrospective study, to identify the relationship between body mass index (BMI), low-density lipoprotein cholesterol (LDL-C) levels and myocardial perfusion in patients without established atherosclerotic cardiovascular diseases.

Material and methods. The study included 534 patients with cardiovascular risk factors but without established coronary artery disease, diabetes, myocardial infarction or coronary revascularization. In 76 of them, stress/rest myocardial perfusion single-photon emission computed tomography (SPECT) was performed.

Results. The relationship between BMI and LDL-C levels is described by a quadratic (r2=0,21, p<0,001) function or a linear spline kinked in BMI of 27 kg/m2 (r=0,51, -0,46 — before and after this value, respectively; p<0,001). According to SPECT, focal stable and transient left ventricular myocardial perfusion abnormalities were not detected. However, there was a direct linear correlation between the heterogeneity of rest myocardial perfusion (ohet) and BMI (r=0,43, p<0,001), ohet and waist circumference (r=0,40, p<0,001), as well as between ohet and LDL-C (r=0,44, p<0,001).

Conclusion. The relationship between BMI and LDL-C levels can be explained by endocrine dysfunction of adipose tissue, which disturbs the synthesis and metabolism of atherogenic lipoproteins. Obesity and increased LDL-C levels affect myocardial perfusion both by aggravating coronary atherogenesis and by microcirculatory disorders. Rest myocardial perfusion SPECT can be a method of screening for myocardial disorders caused by both diffuse atherosclerosis and metabolic syndrome.

Nuclear imaging of chemotherapy-induced cardiotoxicity

The high efficiency of modern chemotherapy has made it possible to achieve great success in the treatment of cancer. Cardiovascular adverse effects are a major disadvantage of anticancer therapy, often requiring low and less effective doses or even drug withdrawal. Nuclear imaging techniques are the most sensitive in early detection of left ventricular damage and dysfunction during chemotherapy. This review presents modern data on the potential of nuclear imaging of cardiotoxicity.

[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.

NUCLEAR IMAGING IN SUDDEN CARDIAC DEATH RISK ASSESSMENT

Sudden cardiac death is a cause of fatal outcomes in large proportion of cardiovascular patients. Left ventricle ejection fraction at the moment is the main criteria for sudden cardiac death risk stratification, however the parameter is not enough reliable. Nuclear imaging methods make it to visualize finer pathophysiological processes representing the probability of the life threatening ventricular arrhythmias development. The review is focused on recent data on nuclear imaging for cellular perfusion assessment, transient ischemia, vitality of myocardium and myocardial blood flow, metabolic disorders and sympathetic innervation.

[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]

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.

[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.

[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 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 2–3) = 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 1–3) = 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 1–4) = 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 1–4)=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.

[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.

[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.

[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.

[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.

[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.

[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.

[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.

[An experience of the use of stem cells in the treatment of patients with myocardial infarction and low ejection fraction]

We present our own experience of assessment of effect of cell therapy on functional state of the myocardium in patients with lowered contractile capacity of the left ventricular myocardium. Intracoronary administration of stem cells in acute myocardial infarction is a safe method of treatment. It does not cause additional damage of the myocardium and does not provoke appearance of malignant arrhythmia. Cell therapy does not affect global left ventricular function. Data we have obtained demonstrate tendency to improvement of myocardial contractile function in dynamics in the majority of studied patients, including patients of the comparison group. This most probably indicates that the given process has been caused by restoration of blood flow to surviving cardiomyocytes after transluminal coronary angioplasty and improvement of function. Confirmation of participation of administered cells in myocardial contraction and improvement of perfusion requires further clinical investigations.

[The role of multidetector computed tomography in detection of myocardial infarction]

The aim of the study was to assess the diagnostic value of multidetector computed tomography (MDCT) in detection of myocardial infarction (MI) in acute and chromic stages.

MATERIAL AND METHODS

49 patients with suspected MI were included in the study. In 44 patients the diagnosis of acute MI had been confirmed according to standard criteria. Contrast-enhanced MDCT of the heart and vessels was performed with 4-row MDCT scanner.

RESULTS

MDCT detected areas of MI in 39 of 44 patients with proven MI. In 66,7% of cases they were transmural and in 33,3% -- subendocardial. In arterial phase the density of infarcted area was significantly lower than in normal myocardium (mean, 32,6 +/- 3,7 HU versus 101,9 +/- 3,7 HU, correspondingly, p < 0,0001). Mean values of myocardial density in the area of the MI did not change during follow-up (32,6 +/- 3,7 HU vs 41,3 +/- 4,5 HU, ns). In comparison to SPECT, sensitivity and specificity of MDCT in detection of transmural MI were 96,9% and 100%. corr. In the whole group of patients, taking results of troponin test as a gold standard, the sensitivity of MDCT in detection of Q-MI and non-Q MI were 89,1% and 93,5%, correspondingly.

CONCLUSION

Cardiac MDCT can reliably detect and localize areas of acute and chronic MI. Contrary to SPECT, it also gives information about stenosis and occlusions in the coronary arteries.

[Radiodiagnostic studies in atherosclerosis]

Due to the fact that it is necessary to make a detailed assessment of the implication of atherosclerotic lesion in the development of coronary heart disease and to timely detect the instability of the process, there is a need for developing new methods for imaging atherosclerosis. Coronary angiography and radionuclide studies are known to be of importance in the diagnosis of atherosclerosis. Of particular interest is combined positron emission and X-ray tomography using 18FDG, which determines not only the site and degree of an atherosclerotic process, but also its activity.

[Prediction of results of antiarrhythmic drug therapy in patients with malignant ventricular tachyarrhythmias, based on the prognostic value of left ventricular contractility parameters]

In 44 patients (3 women and 41 men, mean age 54 +/- 11 years) with malignant ventricular tachyarrhythmias (MVT) we assessed dependence of results of testing of antiarrhythmic drugs and efficacy of their long term use for prevention of recurrences of MVT on topography of derangement of local left ventricular (LV) contractility. Regional LV contractility was assessed with transthoracic echocardiography and radionuclide ventriculography (RNV). Testing of antiarrhythmic drugs was performed under control of repetitive intracardiac electrophysiological studies. Duration of follow-up was 28 (13 - 61) months. According to ROC-analysis most precise markers of positive results of drug testing were values of local ejection fraction (EF) in apical LV segment (10th segment on RNV) above 55%. Signs predisposing to absence of MVT recurrences during long term use of antiarrhythmic drugs were lack of mitral regurgitation (above I degree) according to echocardiography data, values of local EF in segment of lateral LV wall (4th segment on RNV) exceeding 42%, or value of LV end diastolic volume less than 365 ml according to RNV data. Parameters of local LV contractility are most precise markers of results of the use of antiarrhythmic drugs in patients with MVT, their diagnostic value is hair than that of global LVEF. Efficacy of antiarrhythmic drugs at electrophysiologic testing and long term follow-up are associated with different parameters of local LV contractility.

[The role of noninvasive methods of investigation in diagnosis of atherosclerosis]

Visualization of the myocardium with the use of various high technologies gains more and more important significance in diseases of cardiovascular system. Large value for investigations of the heart and blood vessels have acquired methods of echocardiography, magnetic resonance tomography, spiral computed tomography, as well as large spectrum of methods of nuclear cardiology. Contemporary value of instrumental methods of investigation for diagnostics of atherosclerosis is discussed in this paper and diagnostic possibilities of various techniques for assessment of the state of myocardium, pathological changes of vascular wall and for visualization of atherosclerotic plaques (AP) are presented. Advantages and drawbacks of methods, their complex application for objective analysis of changes in AP and their clinical significance are considered. Special accent is made on early diagnosis of pathological derangements, because full value information allows making adequate decisions about subsequent curative measures. It is shown that detection and evaluation of early signs of atherosclerosis appears to be determining factor of efficacy of treatment. In patients without obvious symptoms of ischemic heart disease or at the background of postinfarction cardiosclerosis nuclear cardiology with assessment of myocardial perfusion by single photon emission computed tomography and positron emission tomography (PET) appears rather valuable for assessment of viability even when coronary arteries are unchanged. Important significance for detection of cardiosclerosis has also acquired spiral computed tomography, which allows to reveal calcium in blood vessels. The use of multislice computed tomography in perspective might partially replace coronary angiography especially for assessment of degree of stenoses and patency of grafts. On initial stages of atherosclerosis information on AP structure especially on the presence of inflammatory component is very important. Definite successes become noticeable with application of magnetic resonance tomography for detection of AP. However, probably, further perfection of equipment and methodological approaches with the use of novel contrasts is necessary. In this plane definite successes are achieved by PET and combined examinations by methods of PET/CT integrating advantages of both techniques.

[Myocardial contractility evaluation by radionuclide 4D-tomoventriculography in patients with ischemic heart disease]

AIM

To estimate the capabilities of the new technique radionuclide 4D-tomoventriculography (4D-RTVG) versus conventional methods, such as radionuclide equilibrium ventriculography (REVG), ECG-synchronized single photon emission computerized tomography (SPECT), and echocardiography (EchoCG), in the evaluation of systolic and diastolic dysfunction in patients with coronary heart disease (CHD).

MATERIALS AND METHODS

The study included 29 patients (19 males and 10 females) aged 43 to 66 years who had CHD. The diagnosis of CHD was established on the basis of coronary angiographic findings when the signs of coronary atherosclerosis were found. All the patients underwent 4D-RTVG, REVG, myocardial ECG-synchronized SPECT, and Echo CG.

RESULTS

There was a strong correlation of the values obtained by 4D-RTVG versus REVG and EchoCG when ejection fraction and left ventricular (LV) end-diastolic volume and the indices reflecting LV blood filling and ejection velocity were estimated. The correlation between the values provided by 4D-RTVG and myocardial ECG-synchronized SPECT females was slightly weaker.

CONCLUSION

The findings suggest that 4D-RTVG is highly reliable in evaluating both LV systolic and diastolic functions. That fact the technique is easy-to-use and mini-invasive shows that it may be clinically applied.

[Study of the impact of intramyocardial implantation of stem cells on myocardial perfusion and contractility in patients with coronary heart disease concurrent with postinfarct cardiosclerosis and chronic heart failure]

OBJECTIVE

to study of intramyocardial implantation of cultured bone marrow stem cells on myocardial perfusion and contractility in the surgical treatment of patients with coronary heart disease (CHD) and chronic heart failure (CHF), by synchronized single-photon emission computed tomography (SSPECT) of the myocardium.

SUBJECTS AND METHODS

The study included 11 patients. Intramyocardial injection of cell injections into the myocardial periscarring areas was made at coronary bypass surgery. All the patients underwent 99mTc myocardial SSPECT MIBI before and 3, 6, 12 months after surgery.

RESULTS AND CONCLUSIONS

Implantation of bone marrow stem cells into the left ventricular myocardium favorably affects left ventricular remodeling and contributes to the improvement of myocardial perfusion and contractility, as evidenced by 99mTc.

[Imaging of inflammatory foci with 99m technecium labeled antimicrobial oligopeptide]

A direct method using 99mtechnecium to label the synthetic antimicrobial oligopeptide ubiquicidine with a molecular mass of 1.7 kDa has been developed. The radiochemical purity of the resultant labeled compound was more than 98%. A combination of ubiquicidine and 99mtechnecium showed stability in blood plasma. The biological study indicated that the complex was renally excreted from blood flow rapidly (the half-life is 30 min). It accumulated in the experimental inflammatory focus of laboratory animals, peaking 1-2 hours after intravenous injection when the inflammatory focus/intact tissue ratio amounted up to 2.6-3.4, which could yield satisfactory abscess scintigrams. The findings make it possible to consider ubiquicidine as a promising compound for the design of radiopharmaceutical to image inflammatory foci.

[Cardiac sympathetic innervation in patients with ventricular arrhythmias: an assessment by 123I-metaiodobenzylguanidine scintigraphy]

The aim of this study was to determine the state of sympathetic innervation in patients with ventricular arrhythmias (VA) using 123I-metaiodobenzylguanidine 123I -MIBG) scintigraphy. Fifty six patients (26 men and 30 women, mean age 37.4+/-11,6) underwent single-photon emission computed tomography (SPECT) imaging and planner scintigraphy after injection of 123I-MIBG (activity 148 MBq). They form three groups. Thirty patients with idiopathic VA (IVA) were included in group I: 14 patients with ventricular extrasystoles (VE) and 16 - with ventricular tachycardias (VT). Group II was formed by 17 patients (with dilated cardiomyopathy, n=7 and chronic myocarditis, n=10), 6 of them had VE and 11 - VT. The control group III was formed by 9 healthy subjects with structurally normal heart without VA. We analyzed early (30 minutes) and delayed (4 hours) images after 123I-MIBG administration. The global sympathetic activity (SA) was assessed by heart/mediastinum ratio and washout rate. Regional SA was assessed by extent and severity of defect. In group I 25 of 30 patients (83.3%) had regional SA abnormalities significantly different from controls (p<0.001). At the same time global uptake of 123I-MIBG in this group was not affected. In group II regional SA abnormalities were revealed in all patients (100%) and global reduction of 123I-MIBG uptake - in 14 patients (82.4%). Regional and global SA abnormalities in group II were different from controls (p<0.0001) and patients with IVA (p<0.001). There was no difference in SA abnormalities between patients with VE and VT. Our results suggest that patients with different VA have abnormalities of sympathetic innervation, including patients with structurally normal heart.

[Body mass loss due to orlistat therapy and multiple factors of cardiovascular risk]

AIM

To study effects of body mass loss due to orlistat on carbohydrate and lipid metabolism, insulin resistance, 24-h profile of arterial pressure (AP), left ventricular myocardial hypertrophy, brain perfusion in patients with metabolic syndrome (MS).

MATERIAL AND METHODS

Thirty middle-aged patients with MS entered the trial. They received orlistat in a dose 120 mg twice a day for 24 weeks. Before and after the treatment the patients' carbohydrate and lipid metabolism, insulin resistance were studied, 24-h monitoring of arterial pressure, echo-cardiography were made. Brain perfusion was studied with single-photon emission computed tomography in 18 patients. Results. All the patients lost much weight. This was accompanied with improved indices of AP profile, metabolism of carbohydrates and lipids, insulin resistance, left ventricular hypertrophy, brain perfusion. Conclusion. Orlistat treatment weakens basic factors of cardiovascular risk.

[Primary prophylaxis of cerebrovascular complications in patients with metabolic syndrome]

AIM

To study effects of antihypertensive therapy with bisoprolol and actovegin on cerebral perfusion in patients with metabolic syndrome.

MATERIAL AND METHODS

Thirty patients (18 women and 12 men) with metabolic syndrome and mild arterial hypertension took bisoprolol alone in a dose 5-10 mg/day, and fifteen patients received combined therapy (bisoprolol and actovegin) for 12 weeks. Before the study and 12 weeks later measurements were made of carbohydrate and lipid metabolism, single photon emission computed tomography investigated brain perfusion.

RESULTS

Improvement of brain perfusion was observed after both monotherapy with bisoprolol and its combination with actovegin.

CONCLUSION

Monotherapy with bisoprolol and bisoprolol combination with actovegin improved brain perfusion but the combination was more effective.

[Cerebral perfusion in patients with metabolic syndrome]

Cerebral perfusion was studied in patients with arterial hypertension combined with metabolic syndrome and diabetes mellitus type II. The data is compared to the results obtained for patients with a single disorder--metabolic syndrome, diabetes mellitus type II and arterial hypertension without metabolic alterations. It is shown that patients with disregulation of carbohydrate and lipid metabolism are more vulnerable to cerebral blood supply alterations. A level of perfusion was the same in patients with metabolic syndrome and diabetes mellitus type II. Besides, an acetazolamide application revealed that patients with metabolic syndrome had reduced cerebral vascular autoregulation.

[Impairment of cardiac sympathetic function in patients with acute myocardial infarction and unstable angina]

AIM

To assess the state of sympathetic innervation of the heart in patients with acute coronary syndrome.

MATERIAL

Patients with Q-myocardial infarction (MI, n=36), non-Q-MI (n=13), and unstable angina (UA, n=9).

METHODS

Each subject underwent single-photon emission computed tomography (SPECT) and planar scintigraphy using iodine-123 metaiodobenzylguanidine ((123)I-MIBG) for assessment of cardiac sympathetic function. We analyzed early (15 minutes) and delayed (4 hours) images after (123)I-MIBG administration. Resting (99m)Tc-MIBI myocardial scintigraphy was performed for evaluation of myocardial perfusion. Location, extent (%) and severity (Un.) of defects were determined using <<CEqual 3.0>> program. (123)I-MIBG did not accumulate in myocardium of 3.5% patients. All other patients demonstrated (123)I-MIBG accumulation defects. These defects were colocolized with (99m)Tc-MIBI uptake abnormalities. However both extent and severity of sympathetic innervation defects exceeded those of perfusion defects in all patients. Mean extent and severity of sympathetic neuronal damage areas were the greatest in patients with Q-MI (41+/-8% and 1119+/-377 Un. respectively) and the least in patients with UA (22+/-12% and 602+/-353 Un., respectively). On the contrary the mean extent of areas with sympathetic endings dysfunction but normal perfusion was the largest in UA group and the least in Q-MI group (18+/-11 and 10+/-7%, respectively, p<0,05).

CONCLUSION

Impairment of cardiac sympathetic function in patients with acute coronary syndrome could be detected by SPECT with (123)I-MIBG. Locations of (123)I-MIBG and (99m)Tc-MIBI defects were similar but sympathetic dysfunction areas were larger than areas with reduced perfusion. This result suggests higher sensitivity of sympathetic endings to ischemia compared with cardiomyocytes. Myocardial areas with sympathetic endings dysfunction but normal perfusion can be defined as myocardium at risk.

[Cerebrovascular complications in metabolic syndrome: possible approaches to decrease risk]

AIM

To compare brain perfusion in hypertensive patients with diabetes mellitus type 2 (DM2) or metabolic (MS) syndrome and hypertensive patients without clinicobiochemical signs of DM2 or MS; to study enoxaparin effects on brain perfusion in DM2 and arterial hypertension (AH).

MATERIAL AND METHODS

Seventy patients included in the study were divided into three groups: 30 patients with DM2 and AH (group 1), 30 patients with MS and AH (group 2) and 10 AH patients without manifestations of MS or DM2 (group 3). All the patients have undergone single-photon emission computed tomography (SPECT) of the brain, carbohydrate and lipid metabolism were examined.

RESULTS

Deterioration of brain perfusion was more prominent in DM2 and MS patients with AH than in hypertensive patients with normal metabolism. Stress test with acetasolamide revealed defective autoregulation of cerebral blood flow in hypertensive patients with DM2. A 6-week therapy with enoxaparin significantly improved brain perfusion in hypertensive patients with DM2.

CONCLUSION

Enoxaparin treatment of hypertensive DM2 and MS patients with abnormal perfusion of the brain can be used for prevention of cerebrovascular complications.

[Comparative effectiveness of different methods of diagnosis and correction of impaired portal circulation]

The diagnostic effectiveness of X-ray radionuclide and ultrasound determination of portal blood flow and the impact of different treatments on the blood flow were evaluated in 76 patients with hepatic cirrhosis. The treatment regimens were used propranolol (Group 1), isosorbide-5-mononitrate (monosan) (Group 2), and a combined therapy with propranolol in combination with diuretics and a course of intravenous laser irradiation (Group 3). In terms of both clinical and laboratory parameters and the status of portal circulation, the highest effect was observed in the patients receiving the combined therapy.

[Atenolol induced bradycardia in patients with stable angina: effects on exercise tolerance, myocardial perfusion and left ventricular contractility]

AIM

To assess effects of atenolol-induced heart rate decrease on myocardial perfusion, left ventricular contractility and tolerance to exercise in patients with chronic coronary artery disease.

MATERIAL AND METHODS

Twenty eight men (mean age 54,5-/+9,2 years) with stable class I-III angina and positive reproducible result of bicycle exercise test underwent rest/stress 99mTc-MIIBI gated single-photon emission computed tomography (SPECT) before and after 10 days of administration of atenolol (20 patients) or placebo (8 patients). Dose of atenolol was titrated to achieve at least 15% decrease of heart rate from baseline.

RESULTS

After 10 days of treatment with atenolol heart rate decreased from 78-/+3.1 to 59-/+1.1 bpm (p=0.01), whereas in placebo group there were no significant changes. Compared with placebo, treatment with atenolol was associated with significant decreases in extent and severity of perfusion defects, ischemic score and number of ischemic segments. No significant changes of parameters of left ventricular contractility occurred. Treatment with atenolol was associated with symptomatic improvement and increase of the total exercise time.

CONCLUSION

Heart rate lowering during monotherapy with atenolol was associated with improvement of myocardial perfusion and tolerance to exercise.

[Effect of restoration of coronary blood flow on dynamics of myocardial perfusion and function in patients with acute myocardial infarction. Data of gated technetium-99m-sestamibi SPECT]

Effects of coronary blood flow restoration on dynamics of myocardial perfusion and function were studied in 50 patients with acute myocardial infarction during 6-month follow-up. Gated SPECT with 99mTc-MIBI (G-SPECT) was performed before onset of reperfusion procedures, in 24 hours, 10 days, 1 and 6 months. In patients with successful reperfusion (n=36) perfusion defect (PD) size decreased by 6.78+/-0.97% (p<0.001) and its severity by 221.3+/-85 std (p<0.001) in 24 hours. In 10 days PD size decreased by 3.9+/-0.88% (r<0.05) and severity by 149+/-39 std (p<0.05), whereas in 1 month PD size decreased by 2,18+/-1,4% (p<0.05), PD severity by 146.3+/-67 std (p<0.05). Successful reperfusion was associated with improvement of contractility: left ventricular ejection fraction increased by 3% (p<0.05) on day 10 of the disease. In patients with failed reperfusion PD size and severity decreased in 10 days by 4.8+/-4.2%, p<0.05, and 276+/-75 std, p<0.05, respectively, in 6 months PD size decreased by 3.1+/-0.9%, p<0.05, left ventricular ejection fraction did not change during follow-up. We conclude that successful reperfusion therapy promotes restoration of myocardial perfusion and improvement of its contractility.

[Evaluation of myocardial perfusion in patients with hypertrophic cardiomyopathy in comparison with clinical and echocardiographic data]

AIM

To study peculiarities of myocardial perfusion in patients with hypertrophic cardiomyopathy (HCMP) in correlation with clinical and echocardiographic data.

MATERIAL AND METHODS

62 patients with HCMP (23 females and 39 males, mean age 44.4 +/- 11.2 years, the disease duration 13.0 +/- 10.4 years) have undergone ECG, 24-h ECG monitoring, echocardiography, perfusion scintigraphy of the myocardium with 99m-TcMIBI at rest and in combination with bicycle ergometry. The patients were divided into two groups: 35 patients of group 1 had moderate left ventricular hypertrophy (the septal thickness in diastole under 20 mm; 27 patients of group 2 had severe hypertrophy (the thickness was over 20 mm).

RESULTS

Dyspnea and syncopal states occurred more frequently in patients from group 2. They also had a higher functional class of heart failure (2.0 +/- 0.8 and 1.2 +/- 0.7 for group 1 and 2, respectively, p < 0.05). Cardiac performance was significantly higher in patients of group 1. The size of the left atrium, left ventricular myocardium mass, the septal thickness and thickness of posterior wall of the left ventricle, gradient of pressure in the outflow tract of the left ventricle proved higher in patients of group 2. Deep stable defects of myocardial perfusion were detected in 5 (15%) patients of group 1 and 10 (37%) patients of group 2. Transient defects of myocardial perfusion were found in 9 (26%) patients of group 1 and 12 (44%) patients of group 2. The index of myocardial ischemia in group 1 patients was significantly lower than in patients of group 2 (3.5 +/- 2.2 and 8.3 +/- 2.5, respectively, p < 0.05).

CONCLUSION

Patients with severe hypertrophy of the left ventricle had severe clinical picture, low exercise tolerance, marked hemodynamic changes, more frequent defects of left ventricular perfusion defects compared to patients with moderate hypertrophy of the left ventricular myocardium.

[Preliminary data on combined assessment of tolerance to exercise, left ventricular contractile function in ischemic heart disease patients taking bradycardic agents]

AIM

To study effects of bradicardia induced by atenolol, diltiazem and ivabradin on exercise tolerance, myocardial perfusion and left ventricular contractile function in patients with stable angina pectoris.

MATERIAL AND METHODS

The trial included 7 male patients aged 57 +/- 2.6 years with coronary heart disease, stable angina of functional class II free of cardiac failure and severe arterial hypertension, with a positive and reproducible VEM test after therapy discontinuation. For 10 consecutive days with 5-day intervals, all the patients received atenolol, diltiazem, ivabradin in doses lowering heart rate at rest by 20% from the initial level. Before the treatment all the patients were studied with VEM test, perfusion synchronized single-photon emission computerized tomoscintigraphy of the myocardium (PSSPECT) at rest and exercise. On day 10 of each drug intake PSSPECT and VEM test were performed if the expected heart rate was achieved.

RESULTS

Each of the studied drugs resulted in a 22-24% reduction in the heart rate at rest accompanied by a significant rise in exercise tolerance, improvement of performance and myocardial perfusion. There were no significant changes in left ventricular contractility.

CONCLUSION

A 20% reduction in resting heart rate due to monotherapy with drugs having a bradicardic effect leads to positive changes in exercise tolerance and myocardial perfusion.

[Comparative assessment of resting myocardial perfusion in patients with postinfarct cardiosclerosis by electron-beam tomography and 99mTc-MIBI myocardial single-photon tomography]

The purpose of the study was to compare myocardial perfusion assessed by electron beam computed tomography (EBCT) with that obtained by 99mTc-sestamibi single photon emission computed tomography (SPECT) in patients with old myocardial infarction and control subjects at rest. A total of 42 patients with suspected and known ischaemic heart disease (IHD) were included in the study. 20 pts had a history of Q-wave myocardial infarction (MI), 12 pts had an old non-Q-wave MI and 10 served as controls (without perfusion defects on SPECT images at rest). Assessment of the myocardial perfusion by EBCT was performed using the short axis view and multislice mode (MSM) during injection of 50 ml of the nonionic contrast medium at 4 ml/s via cubital vein. Perfusion defects were localized by SPECT according to 6-segment model of the LV (septal, anterior, lateral, posterior, inferior and apical). Overall concordance between EBCT and SPECT was 67% for normal versus abnormal perfusion. Agreement between the 2 methods for each of the 6 segments was 81% (K = 0.62) for the anterior segment, 71% (K = 0.42) for the septal segment, 71% (K = 0.43) for the apical, 69% (K = 0.3) for the lateral segment, 48% (K = 0.13) for the posterior segment and 60% (K = -0.13) for the inferior segment. Discrepancies between the two of techniques were most notable in the posterior region. Beam hardening during passage of the contrast medium through the heart chambers and descending aorta is possible explanation of the artifacts on EBCT images. This study demonstrates that nowadays EBCT is not yet alternative to SPECT in the assessment of the myocardial perfusion in patients and further improvements of scanning techniques are necessary.