Diagnostics Of Myocardial Infarction Research Articles

Detecting early myocardial ischemia in rat heart by MALDI imaging mass spectrometry

Diagnostics of myocardial infarction in human post-mortem hearts can be achieved only if ischemia persisted for at least 6–12 h when certain morphological changes appear in myocardium. The initial 4 h of ischemia is difficult to diagnose due to lack of a standardized method. Developing a panel of molecular tissue markers is a promising approach and can be accelerated by characterization of molecular changes. This study is the first untargeted metabolomic profiling of ischemic myocardium during the initial 4 h directly from tissue section. Ischemic hearts from an ex-vivo Langendorff model were analysed using matrix assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) at 15 min, 30 min, 1 h, 2 h, and 4 h. Region-specific molecular changes were identified even in absence of evident histological lesions and were segregated by unsupervised cluster analysis. Significantly differentially expressed features were detected by multivariate analysis starting at 15 min while their number increased with prolonged ischemia. The biggest significant increase at 15 min was observed for m/z 682.1294 (likely corresponding to S-NADHX—a damage product of nicotinamide adenine dinucleotide (NADH)). Based on the previously reported role of NAD+/NADH ratio in regulating localization of the sodium channel (Nav1.5) at the plasma membrane, Nav1.5 was evaluated by immunofluorescence. As expected, a fainter signal was observed at the plasma membrane in the predicted ischemic region starting 30 min of ischemia and the change became the most pronounced by 4 h. Metabolomic changes occur early during ischemia, can assist in identifying markers for post-mortem diagnostics and improve understanding of molecular mechanisms.

Редкий случай развития инфаркта миокарда 2-го типа у пациента с синдромом Вольф-Паркинсон-Уайта

Currently, myocardial infarction diagnostics has no diffi culties. Type 2 myocardial infarction is an exception, as it occurs due to a mismatch with oxygen delivery along coronary arteries and myocardial demand for it. Th e disease is secondary and this is the main diffi culty for its diagnostics. The article described a case of a young man having Wolff -Parkinson-White syndrome with type 2 myocardial infarction development. The main cause of myocardial necrosis is a prolonged paroxysm of reciprocal atrioventricular antidromic tachycardia.

Тропонин I и Д-димер в диагностике инфаркта миокарда

Тропонин I и Д-димер в диагностике инфаркта миокарда

Difficulties of diagnostics of acute myocardial infarction in elderly and senile patients and their influence on management in the acute period of disease

Aim. To study the features of disease progress and approaches to the diagnostics of acute myocardial infarction (MI) among elderly and senile patients and their influence on the management in the acute period of disease.Materials and methods. The study was performed using the WHO program “Register of acute myocardial infarction” (Tomsk). The study included 410 patients (60 years and older), who had acute MI. The study group is represented by a comparable number of men (n=212) and women (n=198). The mean age of patients was 71 (66; 77) years (women are 5 years older than men (p<0,001)). Statistical processing was performed using the program Statistica V10.0.Results. Most of the patients had history comorbid pathology. In one in five patients (17,8%), the disease had an atypical manifestations, which in 41% of cases was represented by the asymptomatic form. Atypical manifestation of MI lengthened the prehospital phase of medical care due to a longer time before the first medical contact (p=0,005), as well as a late help-seeking (120 [49; 311,5] minutes). In 28% of patients, the level of creatine kinase-MB remained normal, and the indicator of troponin I exceeded the maximum values only in half of the cases. One fifth of the patients underwent acute MI treatment in non-core hospitals, which resulted in a low frequency of intervention (38%) and increasing by 2 times the chance of death within 5 years. The level of hospital mortality from acute MI in elderly patients in noncore hospitals was 3 times higher than in specialized departments (p<0,001).Conclusion. Difficulties in diagnostics of MI in patients of older age groups is caused by the prevalence of comorbid pathology, an atypical manifestations of the disease and low information content of biochemical markers of myocardial necrosis. It leads to an increase in time delays at the prehospital phase and frequent hospitalization of patients in non-core hospitals, making it impossible for them to receive timely, preferred therapy.

MFB-CBRNN: A Hybrid Network for MI Detection Using 12-Lead ECGs.

This paper proposes a novel hybrid network named multiple-feature-branch convolutional bidirectional recurrent neural network (MFB-CBRNN) for myocardial infarction (MI) detection using 12-lead ECGs. The model efficiently combines convolutional neural network-based and recurrent neural network-based structures. Each feature branch consists of several one-dimensional convolutional and pooling layers, corresponding to a certain lead. All the feature branches are independent from each other, which are utilized to learn the diverse features from different leads. Moreover, a bidirectional long short term memory network is employed to summarize all the feature branches. Its good ability of feature aggregation has been proved by the experiments. Furthermore, the paper develops a novel optimization method, lead random mask (LRM), to alleviate overfitting and implement an implicit ensemble like dropout. The model with LRM can achieve a more accurate MI detection. Class-based and subject-based fivefold cross validations are both carried out using Physikalisch-Technische Bundesanstalt diagnostic database. Totally, there are 148 MI and 52 healthy control subjects involved in the experiments. The MFB-CBRNN achieves an overall accuracy of 99.90% in class-based experiments, and an overall accuracy of 93.08% in subject-based experiments. Compared with other related studies, our algorithm achieves a comparable or even better result on MI detection. Therefore, the MFB-CBRNN has a good generalization capacity and is suitable for MI detection using 12-lead ECGs. It has a potential to assist the real-world MI diagnostics and reduce the burden of cardiologists.

SIGNIFICANCE OF COPEPTIN IN DIAGNOSTICS OF MYOCARDIAL INFARCTION

In the review, studies results are presented on the significance of laboratory marker copeptin in diagnostics of myocardial infarction (MI) and further prognosis evaluation. Copeptin (surrogate marker of vasopressin) represents the severity of endogenic neurohormonal stress and significantly increases in blood during the first hour of MI course, declining at tenth hour from onset. Negative values of copeptin and troponin T make it with high grade of credibility to rule out MI. Grade of copeptin increase correlates with the size of myocardium necrosis focus and further prognosis of the disease: sudden death risk and progression of chronic heart failure.

Of MIs and men--a historical perspective on the diagnostics of acute myocardial infarction.

The history of myocardial infarction (MI) diagnostics has gone through a continuous evolution over the past century, when several new discoveries have contributed to remarkably increase the number of patients appropriately diagnosed with this condition. The tale "of MIs and Men" displays rather a long history, since atherosclerosis was found to be present in humans several centuries before modern civilization and the identification of the most prevalent risk factors. It was only at the end of the 19th century and at the beginning of the 20th century that the physicians acknowledged that MI is principally sustained by coronary thrombosis, and that the clinical picture of MI could be subsequently confirmed at autopsy. With the first description of the electrocardiogram (ECG) in the 1910s and 1920s, the history of modern MI diagnostics really began. Additional important discoveries followed, which are mainly represented by radiography, echocardiography, computed tomography, and magnetic resonance imaging of the heart. Another major breakthrough occurred at the down of the third millennium, with the development of commercial immunoassays for the measurement of cardiac troponin I and T, which represent now the cornerstones for identifying any kind of myocardial injury, thus including MI. The major advancements in the understanding of MI pathophysiology and the progressive introduction of efficient diagnostic tools will be described and discussed in this narrative historical review.

Проблеми та сучасні можливості діагностики інфаркту міокарда

У зв’язку з тим, що виявлення інфаркту міокарда в Україні вкрай недостатнє, проаналізовані сучасні можливості та нові біохімічні методи дослідження цього захворювання та перспективи оптимізації діагностики на різних етапах надання медичної допомоги.

THE EFFICACY OF COMBINED BIOMARKER TESTS IN EARLY DIAGNOSTICS OF ACUTE MYOCARDIAL INFARCTION AFTER CLINICAL SYMPTOMS ONSET: ROLE OF HEART-TYPE FATTY ACID-BINDING PROTEIN

Aim. To evaluate the diagnostic value of heart-type fatty acid-binding protein (H-FABP) introduction to standard cardiac biomarkers in diagnostics of myocardial infarction (MI) early after clinical symptoms onset. Material and methods. Patients aged 18 years and older admitted to the hospital with acute coronary syndrome (ACS) during first 6 hours after ACS symptoms onset were enrolled into the study. At hospitalization level of biomarkers of myocardial damage (creatine phosphokinase-MB fraction - CPK-MB, troponin T) and qualitative tests on FABP were assessed in all patients. Serum troponin T concentration measured in 12 hours after the hospitalization was used to confirm diagnosis of MI. Moreover , diagnosis of MI was verified by echocardiography with the assessment of local reduction in myocardial contractility. Results. 101 patients were included into the study (27% female; aged 59.9±12.4). At the moment of hospitalization 71 (70%) patients were diagnosed with ACS with ST-segment elevation, and 30 (30%) patients - ACS without ST-segment elevation. In total, period between clinical symptoms onset and hospitalization was 3.6±1.4 hours. Analysis of diagnostic value of tests during the first 6 hours after ACS symptoms onset showed higher sensitivity of H-FABP in comparison with troponin T and CPK-MB (72.5, 56.2 and 49.5%, respectively). Specificity of these tests during the first 6 hours after onset of clinical signs of ACS was 90, 100 и 90%, respectively. Sensitivity and specificity were 87.7 and 100.0%, respectively , when H-FABP , troponin T and CPK-MB were used in combination as a “block test” in patients hospitalized during the first 6 hours after ACS symptoms onset. Sensitivity and specificity were 74.3 и 100.0%, respectively , when “block test” was used in patients hospitalized during the first 3 hours after ACS symptoms onset; between 3 and 6 hours after ACS symptoms onset sensitivity and specificity of tests reached 100%. Conclusion. “Block test” with H-FABP , troponin T and CPK-MB early after ACS symptoms onset is more sensitive in comparison with separate use of the tests.

Enzymatic diagnosis of coronary heart disease

The importance of enzyme diagnostics of myocardial infarction is currently beyond doubt. Determination of asparagine and alanine transaminases activity has been replaced by the study of more sensitive so-called "cardiospecific" enzymes: creatine phosphokinase, lactate dehydrogenase and their isoenzymes. LDH isoenzyme1 has special specificity to the heart muscle, the content of which is studied by hydroxybutyrate dehydrogenase activity (-HBDH). However, the patterns of changes in the activity of this enzyme in various forms of ischemic heart disease remain insufficiently studied. The content of -glutamyl transpeptidase enzyme in cardiac muscle is insignificant; however, there are reports in the literature about increased activity of this enzyme in the acute period of myocardial infarction. The degree of hyperenzymemia in acute myocardial infarction usually correlates with the size of ischemic necrosis focus, so a significant increase in enzyme activity is found in those forms of the disease, which proceed with a clear clinical picture and are accompanied by typical changes on ECG. Meanwhile, clinicians still face difficulties in differential diagnosis of such variants of ischemic heart disease as various forms of angina pectoris, small focal myocardial necrosis, recurrent myocardial infarctions and cardialgia of different genesis. The similarity of their clinical symptomatology and unclear ECG criteria make us return to the analysis of enzyme activity changes in various forms of coronary heart disease.

Mapping of cardiac potentials in diagnostics of myocardial infarction and its weight quantitation.

Mapping of cardiac potentials in diagnostics of myocardial infarction and its weight quantitation.