Принципы построения и базовое алгоритмическое обеспечение систем удаленного мониторинга состояния здоровья больных с нарушениями сердечно-сосудистой системы

Construction principles of remote health monitoring systems for cardiovascular patients are presented. Basic algorithmic support of the system that allowscarrying out detection and sorting of cardiocomplexes with simultaneous accumulation of identical cardiocomplexes is determined.Представлены основные принципы построения систем удаленного мониторинга состояния здоровья больных с нарушениями сердечно-сосудистой системы. Определено базовое алгоритмическое обеспечение указанной системы, позволяющее обнаруживать и сортировать кардиокомплексы с одновременным накоплением идентичных кардиокомплексов

Electrocardiographic signs of impaired depolarization (fragmented QRS, early ventricular repolarization, etc.) as markers of left ventricular systolic dysfunction

Aim. To study the relationship between a decrease in left ventricular (LV) ejection fraction (EF) and conventional electrocardiographic (ECG) signs associated with myocardial structure changes (pathological Q wave, ventricular arrhythmias), and relatively novel and less studied (fragmented QRS (fQRS), early ventricular repolarization (EVR)) and to evaluate their significance for identifying patients with mildly-reduced EF (mrEF).Material and methods. The study included 148 patients who were treated and examined at the Almazov National Medical Research Center. During the ECG analysis, fQRS, EVR, pathological Q wave, and ventricular arrhythmias (VAs) were assessed. Echocardiography data were analyzed. Statistical processing was carried out, including Fisher and chi-squared test, as well as correlation and ROC analysis.Results. Depending on the EF level, patients were divided into three groups: group 1 — patients with reduced EF (rEF) (<40%); group 2 — patients with mrEF (40-49%); group 3 — patients with preserved EF (pEF) (>50%). In the 1st group (with rEF), fQRS was registered in 16 (51,6%) patients, in the 2nd (with mrEF) — in 13 (44,8%), in the 3rd (with EF >50%) — in 16 (18,2%). Pathological Q wave was detected in the 1st group (rEF) in 20 (65%) patients, in the 2nd (mrEF) — in 10 (35%); in the 3rd (pEF) — in 15 (18%) (p<0,001). ROC analysis found that fQRS is more important for identifying patients with mrEF. In the 1st group (rEF), EVR was registered in 2 (6,5%) patients, in the 2nd (pEF) — in 2 (6,9%), in the 3rd (EF>50%) — in 11 (12,5%); the differences were not significant (p=0,5). The relationship of EVR, the number of PVCs and the presence of ventricular tachycardia with EF was not revealed.Conclusion. FQRS is significantly more often observed with a decrease in EF and may be a marker of an mildly-reduced EF. There were no significant correlations between EVR and EF. There was also no relationship between VAs and LV systolic dysfunction

Метод прогнозирования основных показателей кардиопульмонального нагрузочного тестирования для больных с хронической сердечной недостаточностью

Introduction. Cardiopulmonary stress test provides significant diagnostic and prognostic information of the condition of patients with cardiovascular and pulmonary diseases. There is a serious problem, that final phase of stress testing is a physically difficult exercise for a person. There is a significant risk of occurrence and development of pathological conditions of the patient's cardiovascular system. One of the solutions is the development of methods for assessing the biological parameters of the patients at the end of a load protocol based on data from the initial stages of the test.Aim. Development of a method for finding an estimate of the maximum heart rate (HR) and of the peak oxygen consumption (OC) for the patients with chronic heart failure at the end of a cardiorespiratory exercise stress test, based on the results of the study obtained at the first initial stages of the test.Materials and methods. For the study, 149 anonymized records of rhythmograms and data of changes in the oxygen consumption of the patients with chronic heart failure were used. The patients underwent a cardiopulmonary stress test by a bicycle ergometer using step-by-step load protocol (the load power increase at each stage was 10 W, the duration of the load stage was 1 min)Results. Based on the analysis of the data obtained, a method for assessing the peak values of HR and of PC of the patients with chronic heart failure was developed.Conclusion. The relative error of the proposed estimate of the HR peak in most cases was no more than 10 %, which allows it to be used for practical purposes. It was established that when performing 70 % of the stress protocol, the error of the proposed estimate of the OC peak in most cases did not exceed 20 %. More research is needed to improve the accuracy of the assessment for using in medical applications aimed to the modernization of methods and equipment for stress testing of the patients.Введение. Кардиопульмональный нагрузочный тест предоставляет значимую диагностическую и прогностическую информацию о состоянии больных с сердечно-сосудистыми и легочными заболеваниями. Существует серьезная проблема, состоящая в том, что выполнение нагрузочного тестирования испытуемым в его завершающей фазе является физически тяжелым упражнением для человека. Присутствует значительный риск возникновения и развития патологических состояний сердечно-сосудистой системы пациента. Одним из решений данной проблемы является разработка методов оценивания биологических параметров пациентов в конце выполнения нагрузочного протокола на основе данных первых этапов теста.Цель работы. Разработка метода нахождения оценки максимальной частоты сердечных сокращений (ЧСС) и пикового потребления кислорода (ПК) у больных с хронической сердечной недостаточностью (ХСН) в конце выполнения кардиореспираторного нагрузочного стресс-теста на основе результатов исследования, полученных на первоначальных ступенях теста.Материалы и методы. Для проведения исследования использованы 149 обезличенных записей ритмограмм и данных изменения ПК пациентов с ХСН, которые проходили кардиопульмональный нагрузочный тест на велоэргометре с использованием ступенчатого нагрузочного протокола (прирост мощности нагрузки на каждой ступени составлял 10 Вт, длительность ступени нагрузки была равна 1 мин).Результаты. На основе анализа полученных данных разработан метод оценки пиковых значений ЧСС и ПК у больных с ХСН.Заключение. Относительная ошибка предложенной оценки пикового значения ЧСС в большинстве случаев не превосходила 10 %, что позволяет ее использовать для практических целей. Установлено, что при выполнении 70 % нагрузочного протокола ошибка предложенной оценки пикового ПК в большинстве случаев не превосходит 20 %. Необходимы дополнительные исследования для повышения точности данной оценки с целью использования в медицинских приложениях, направленных на модернизацию методов и аппаратуры для нагрузочного тестирования пациентов

Разработка алгоритма кластеризации кардиокомплексов с посткоррекцией для задач длительного мониторирования электрокардиосигнала

Introduction. The most common method for diagnosing cardiovascular diseases is the method of ECG monitoring. In order to facilitate the analysis of the obtained monitorograms, special software solutions for automated ECG processing are required. One possible approach is the use of algorithms for automated ECG processing. Such algorithms perform  clustering of cardiac signals by dividing the ECG into complexes of similar cardiac signals. The most representative complexes obtained by statistical averaging are subject to further analysis.Aim. Development of an algorithm for automated ECG processing,  which performs clustering of cardiac signals by dividing the ECG into complexes of similar cardiac signals.Materials and methods. Experimental testing of the developed software was carried out using patient records provided by the Pavlov First State Medical University of St  Petersburg. The software module was implemented in the MatLab environment.Results. An algorithm for clustering cardiac signals with post-correction for the tasks of long-term ECG monitoring and a software module on its basis were proposed.Conclusion.  The presence of a small number of reference cardiac signal complexes, obtained through ECG processing using the proposed algorithm, allows physicians to optimize the process of ECG analysis. The as- obtained information serves as a basis for assessing dynamic changes in the shape and other parameters of cardiac signals for both a particular patient and groups of patients. The paper considers the effect of synchronization errors of clustered cardiac signals on the shape of the averaged cardiac complex. The classical solution to the deconvolution problem leads to significant errors in finding an estimate of the true form of a cardiac signal complex. On the basis of analytical calculations, expressions were obtained for the correction of clustered cardiac signals. Such correction was shown to reduce clusterization errors associated with desynchronization, which creates a basis for investigating the fine structure of ECG signals.Введение.  Наиболее распространенным методом диагностики сердечно- сосудистых заболеваний является длительное  мониторирование  электрокардиосигнала  (ЭКС) .  Для  облегчения  анализа  полученных  мониторограмм врачам- кардиологам необходимы специальные алгоритмы и программные средства автоматизированной обработки  ЭКС. Одним из  таких средств  является алгоритм автоматизированной обработки  ЭКС, выполня ющий  кластеризацию кардиокомплексов  (КК) , разделяя  ЭКС  на группы максимально близких по форме  КК. Дальнейшему анализу подвергаются только эталонные КК, полученные статистическим  усреднением  КК  в каждой группе.Цель  работы.  Разработка  алгоритма  автоматизированной  кластеризации  КК  ЭКС,  разделяющего  электрокардиосигнал на группы максимально близких по форме КК.Материалы и методы.  Экспериментальная апробация  алгоритма и  программного  модуля  проводилась на  базе обезличенных суточных записей ЭКС пациентов Первого Санкт- Петербургского государственного медицинского университета им.   акад.   И. П. Павлова Минздрава России.  Программный модуль был реализован в среде MatLab.Результаты.  Разработан  алгоритм  сортировки  КК  с  посткоррекцией  для  длительного  мониторирования  ЭКС; представлен программный модуль, реализованный на базе  разработанного алгоритма. Рассмотрено  влияние ошибок синхронизации  КК  при их накоплении  на форму усредняемого КК. Классическое решение задачи деконволюции приводит к значительным ошибкам при нахождении оценки "истинной" формы КК. На основании аналитических расчетов получены выражения для коррекции накапливаемого КК.  Показано, что в результате коррекции можно  нивелировать ошибки накопления, связанные с рассинхронизацией.Заключение.  Наличие  небольшого  количества  эталонных  КК,  полученных  в  результате  обработки  ЭКС с помощью  предложенного  алгоритма,  позволяет  врачу-исследователю  значительно  сократить  время, затрачиваемое  на  анализ  ЭКС,  и  является  основой  исследования  динамических  изменений  формы  и иных параметров КК  как для конкретного пациента, так и для их группы. Полученные результаты  позволяют создать основу для решения задач, направленных на исследование "тонкой" структуры ЭКС

Design principles and basic algorithmic support of remote health monitoring systems for cardiovascular patients

Construction principles of remote health monitoring systems for cardiovascular patients are presented. Basic algorithmic support of the system that allowscarrying out detection and sorting of cardiocomplexes with simultaneous accumulation of identical cardiocomplexes is determined

A Method for Predicting the Main Indicators of Cardiopulmonary Stress Testing for Patients with Chronic Heart Failure

Introduction. Cardiopulmonary stress test provides significant diagnostic and prognostic information of the condition of patients with cardiovascular and pulmonary diseases. There is a serious problem, that final phase of stress testing is a physically difficult exercise for a person. There is a significant risk of occurrence and development of pathological conditions of the patient's cardiovascular system. One of the solutions is the development of methods for assessing the biological parameters of the patients at the end of a load protocol based on data from the initial stages of the test.Aim. Development of a method for finding an estimate of the maximum heart rate (HR) and of the peak oxygen consumption (OC) for the patients with chronic heart failure at the end of a cardiorespiratory exercise stress test, based on the results of the study obtained at the first initial stages of the test.Materials and methods. For the study, 149 anonymized records of rhythmograms and data of changes in the oxygen consumption of the patients with chronic heart failure were used. The patients underwent a cardiopulmonary stress test by a bicycle ergometer using step-by-step load protocol (the load power increase at each stage was 10 W, the duration of the load stage was 1 min)Results. Based on the analysis of the data obtained, a method for assessing the peak values of HR and of PC of the patients with chronic heart failure was developed.Conclusion. The relative error of the proposed estimate of the HR peak in most cases was no more than 10 %, which allows it to be used for practical purposes. It was established that when performing 70 % of the stress protocol, the error of the proposed estimate of the OC peak in most cases did not exceed 20 %. More research is needed to improve the accuracy of the assessment for using in medical applications aimed to the modernization of methods and equipment for stress testing of the patients

Fluorescently Labeled Gadolinium Ferrate/Trigadolinium Pentairon(III) Oxide Nanoparticles: Synthesis, Characterization, In Vivo Biodistribution, and Application for Visualization of Myocardial Ischemia–Reperfusion Injury

Various gadolinium compounds have been proposed as contrasting agents for magnetic resonance imaging (MRI). In this study, we suggested a new synthesis method of gadolinium ferrate/trigadolinium pentairon(III) oxide nanoparticles (GF/TPO NPs). The specific surface area of gadolinium ferrate (GdFeO3) and trigadolinium pentairon(III) oxide (Gd3Fe5O12) nanoparticles was equal to 42 and 66 m2/g, respectively. The X-ray diffraction analysis confirmed that the synthesized substances were GdFeO3 and Gd3Fe5O12. The gadolinium content in the samples was close to the theoretically calculated value. The free gadolinium content was negligible. Biodistribution of the GF/TPO NPs was studied in rats by fluorescent imaging and Fe2+/Fe3+ quantification demonstrating predominant accumulation in such organs as lung, kidney, and liver. We showed in the in vivo rat model of myocardial ischemia–reperfusion injury that GF/TPO NPs are able to target the area of myocardial infarction as evidenced by the significantly greater level of fluorescence. In perspective, the use of fluorescently labeled GF/TPO NPs in multimodal imaging may provide basis for high-resolution 3D reconstruction of the infarcted heart, thereby serving as unique theranostic platform

Comparative Analysis of Diagnostic Plague Antiphage Sera Received from Producers of Different Types

Manufacturing process of ovine hyperimmune sera against Pokrovskaya plague bacteriophage was worked out. Their stability in the process of storage was studied. Sera received were used as raw material to produce three experimental series of diagnostic plague antiphage ovine dry serum. Physicochemical properties, specific activity and specificity of the developed preparation were evaluated in comparison with similar commercial preparation produced from the equine serum. Similarity of all test parameters was revealed that enabled to recommend diagnostic plague antiphage ovine serum for application