Early Detection Of Myocardial Ischemia Research Articles

Cuffless Wearable Sphygmomanometers Using Dual Digital Optical Frequency Combs in Chalcogenide Chips

AbstractSphygmomanometers typically use a rubber cuff around the upper arm to measure blood pressure, but this method can be uncomfortable. Thus, cuffless sphygmomanometers for continuous blood pressure monitoring in emergencies and healthcare are desirable. While electrical and optical blood pressure sensors offer high sensitivity, they often face issues like limited pressure range, temperature drift, slow response, and wearability problems. To tackle these limitations, the study designs a unique cuffless wearable blood pressure sensor (12 mm × 2 mm × 0.5 mm) featuring two original components: a GeSbS/AsS chalcogenide dual‐microring chip for high sensitivity, and a dual digital optical frequency comb (DDOFC) system for fast response and cost‐effective detection. The sensor is comparable to reported electrical and optical blood pressure sensors in its detection limit (23 Pa) but has a ten‐times faster response rate (2 kHz), a 1000‐times longer stable operation (>4.3 × 107 cycles), and a well‐compensated temperature drift (<0.012 pm/°C) that eliminates the need for temperature control. This innovation shows promise for wearable electronics and mobile healthcare, enabling the capture of critical cardiovascular details for applications like in‐surgery monitoring, orthostatic hypotension studies, and early detection of myocardial ischemia and strokes.

Analysis of ST segment alarms in children admitted to the paediatric and cardiac intensive care units and cardiac progressive care unit: a single-centre retrospective study.

ST segment monitoring in the adult population allows for the early detection of myocardial ischaemia. In children admitted to the paediatric intensive care unit (PICU), cardiac intensive care unit (CICU), and cardiac progressive care unit (CPCU), it is unclear if continuous ST segment alarm monitoring is necessary in all patients. All patients admitted to the PICU, CICU, and CPCU during the study period were included. Children with any ST segment alarms were compared with those without an alarm during their stay. The electrocardiogram confirmed true ST segment alarms were compared with all other ST segment alarms. Demographic and clinical data were extracted from the medical record. Medical interventions and procedures occurring around ST segment alarms were recorded for multivariable analysis assessing for the association of true ST segment. Logistic regression was used to evaluate the associations with ST segment alarms during hospital stays. ST segment alarms occurred in 36% of hospital stays, and only 3.4% were considered true. True alarms were significantly more common among patients with a cardiac-related diagnosis, located in both cardiac units, and having received an intervention with any vasoactive medication. In the multivariable logistic regression, patients 11 years or older, hypotension, supraventricular tachycardia, and initiation/escalation of any vasoactive were independently associated with a true ST segment alarm. True ST segment alarms were infrequent, occurring in 1.2% of stays during the study period. Alarm monitoring may be beneficial in those with an underlying cardiac diagnosis.

Myocardial ischemia caused by the synergistic effect of myocardial bridge and moderate stenosis: case report

BackgroundClinical events such as angina pectoris, acute coronary syndrome, and sudden death caused by myocardial bridge (MB) have attracted increasing attention. It is still a challenge to diagnose whether MB can cause the symptoms of patients with MB. For most MB patients, medication remains the primary treatment.Case presentationThis article reports a case of chest pain in a patient with MB in the middle segment of the left anterior descending artery (LADm) with moderate stenosis in the proximal segment (LADp). Through functional assessment, we found that neither MB nor fixed stenosis had sufficient effect on coronary blood flow to cause myocardial ischemia, but their synergistic effect resulted in myocardial ischemia. Finally, a stent was implanted in LADp and good clinical results were achieved.ConclusionsFor symptomatic patients with MB combined with fixed stenosis, functional evaluation may be necessary, which has significant guiding significance for treatment strategy selection. For asymptomatic patients, early detection of myocardial ischemia may also improve the prognosis of patients.

The Value of 2D Global Longitudinal Strain in Predicting the Severity of Coronary Artery Disease in Patients with NSTEMI and Unstable Angina and Regional Strain Value for Predicting the Culprit Artery

Background: Our study aimed to evaluate the predictive ability of resting strain to determine the severity of CAD in the absence of impaired LVEF in patients with NSTEMI and unstable angina. Additionally, the study sought to predict culprit and infracted related artery (IRA) using regional strain (SLR). Methods: The study was conducted between January 2023 and May 2023 at the cardiology department of Ibn Rochd Hospital, Morocco. We conducted a comparative analysis involving 30 patients, comprising 23 individuals with NSTEMI and 7 with unstable angina. In all cases, we assessed both GLS and RLS before proceeding to coronary angiography. Subsequently, we categorized the patients into two groups: one consisted of 18 individuals with severe coronary lesions, including left main trunk (LM) and three vessels lesions, while the other group, comprising 12 patients, served as the control group and had non-severe coronary lesions Results: At resting GLS threshold below -16,3 %, despite its subnormal nature, should raise suspicion and suggest severe coronary artery disease. RLS in the "Single-vessel" group was significantly lower in the culprit artery territories, suggesting that RLS may be a better marker for identifying the culprit artery. Both GLS and the visual analysis of segmental kinetics by WMSI (Wall Motion Score Index) at rest, were statistically significant for detecting severe coronary lesions. Conclusion: GLR and SLR are sensitive markers for early detection of myocardial ischemia and predicting its severity. A resting GLR threshold of less than -16.13% could indicate severe CAD with severe tri-truncular or LMT damage, especially when combined with abnormal WMSI scores. These 2D strain parameter changes precede subjective abnormalities in segmental kinetics, which are often considered normal at rest.

Ultra-High-Resolution Electrocardiography Enables Earlier Detection of Transmural and Subendocardial Myocardial Ischemia Compared to Conventional Electrocardiography.

The sensitivity of exercise ECG is marginally sufficient for the detection of mild reduction of coronary blood flow in patients with early coronary atherosclerosis. Here, we describe the application of a new technique of ECG registration/analysis-ultra-high-resolution ECG (UHR ECG)-for early detection of myocardial ischemia (MIS). The utility of UHR ECG vs. conventional ECG (C ECG) was tested in anesthetized rats and pigs. Transmural MIS was induced in rats by the ligation of the left coronary artery (CA). In pigs, subendocardial ischemia of a variable extent was produced by stepwise inflation of a balloon within the right CA, causing a 25-100% reduction of its lumen. In rats, a reduction in power spectral density (PSD) in the high-frequency (HF) channel of UHR ECG was registered at 60 s after ischemia (power 0.81 ± 0.14 vs. 1.25 ± 0.12 mW at baseline, p < 0.01). This was not accompanied by any ST segment elevation on C ECG. In pigs, PSD in the HF channel of UHR ECG was significantly decreased at a 25% reduction of CA lumen, while the ST segment on C ECG remained unchanged. In conclusion, UHR ECG enabled earlier detection of transmural MIS compared to C ECG. PSD in the HF channel of UHR ECG demonstrated greater sensitivity in the settings of subendocardial ischemia.

Changes in circulating ApoJ-Glyc levels in patients with suspected acute coronary syndrome: The EDICA trial

BackgroundMyocardial ischemia induces intracellular accumulation of non-glycosylated apolipoprotein J that results in a reduction of circulating glycosylated ApoJ (ApoJ-Glyc). The latter has been suggested to be a marker of transient myocardial ischemia. ObjectiveThis proof-of-concept clinical study aimed to assess whether changes in circulating ApoJ-Glyc could detect myocardial ischemia in patients attending the emergency department (ED) with chest pain suggestive of acute coronary syndrome (ACS). MethodsIn suspected ACS patients, EDICA (Early Detection of Myocardial Ischemia in Suspected Acute Coronary Syndromes by ApoJ-Glyc a Novel Pathologically based Ischemia Biomarker), a multicentre, international, cohort study assessed changes in 2 glycosylated variants of ApoJ-Glyc, (ApoJ-GlycA2 and ApoJ-GlycA6), in serum samples obtained at ED admission (0 h), and 1 h and 3 h thereafter, blinded to the clinical diagnosis (i.e. STEMI, NSTEMI, unstable angina, non-ischemic). Results404 patients were recruited; 291 were given a clinical diagnosis of “non-ischemic” chest pain and 113 were considered to have had an ischemic event. ApoJ-GlycA6 was lower on admission in ischemic compared with “non-ischemic” patients (66 [46–90] vs. 73 [56–95] μg/ml; P = 0.04). 74% of unstable angina patients (all with undetectable hs-Tn), had ischemic changes in ApoJ-Glyc at 0 h and 89% at 1 h. Initially low ApoJ-Glyc levels in 62 patients requiring coronary revascularization increased significantly after successful percutaneous intervention. ConclusionsCirculating ApoJ-Glyc concentrations decrease early in ED patients with myocardial ischemia compared with “non-ischemic” patients, even in the absence of troponin elevations. ApoJ-Glyc may be a useful marker of myocardial ischemia in the ED setting.

Validation of the detection of ischemia using 12 lead smartphone based electrocardiography - a non-randomized, single blinded, cross-sectional, multicenter study

Background: Reliable and early detection of myocardial ischemia using computer-aided analysis of electrocardiograms (ECG) provides an important reference for early diagnosis of CVD. We developed a 12-lead smartphone-based electrocardiogram (ECG) acquisition and monitoring system (called “Spandan”), and an application to assess underlying ischemia from analysis of electrocardiographic (ECG) signals only. Objectives of this study were to validate the Spandan 12 lead ECG interpretation for accuracy in the detection of Ischemia in comparison to cardiologists’ diagnosis and to evaluate the accuracy of ischemia in comparison to the interpretation of standard 12 lead ECG. Methods: In this multi-center study all patients (n=597) visiting the ECG room at the department of cardiology were enrolled in the study by taking their written consent and explaining the purpose of the study. Results: Mean age was 52.85 years. The male gender (n=344, 57.62%) shows the maximum frequency than female gender. 12 lead Spandan smartphone ECG recorded fewer false positive cases (8 versus 230) and identified greater true negative cases (310 versus 115). Spandan smartphone ECG recorded better specificity (97.4% versus 33.3%) and positive predictive value (87.4% versus 51.4%) as compared to gold standard ECG. The accuracy of interpretation of Ischemia by cardiologists diagnosis through 12 lead Spandan smartphone ECG was better (100%) as compared gold standard (95.3%). Conclusions: Our study highlights the potential of Spandan smartphone ECG in the detection of myocardial ischemia. This may improve patient satisfaction and reduce healthcare costs.

Early detection of myocardial ischemia in resting ECG: analysis by HHT

BackgroundExercise electrocardiography (ECG) is a noninvasive test aiming at producing ischemic changes. However, resting ECG cannot be adopted in diagnosing myocardial ischemia till ST-segment depressions. Therefore, this study aimed to detect myocardial energy defects in resting ECG using the Hilbert–Huang transformation (HHT) in patients with angina pectoris.MethodsElectrocardiographic recordings of positive exercise ECG by performing coronary imaging test (n = 26) and negative exercise ECG (n = 47) were collected. Based on the coronary stenoses severity, patients were divided into three categories: normal, < 50%, and ≥ 50%. During the resting phase of the exercise ECG, all 10-s ECG signals are decomposed by HHT. The RT intensity index, composed of the power spectral density of the P, QRS, and T components, is used to estimate the myocardial energy defect.ResultsAfter analyzing the resting ECG using HHT, the RT intensity index was significantly higher in patients with positive exercise ECG (27.96%) than in those with negative exercise ECG (22.30%) (p < 0.001). In patients with positive exercise ECG, the RT intensity index was gradually increasing with the severity of coronary stenoses: 25.25% (normal, n = 4), 27.14% (stenoses < 50%, n = 14), and 30.75% (stenoses ≥ 50%, n = 8). The RT intensity index of different coronary stenoses was significantly higher in patients with negative exercise ECG, except for the normal coronary imaging test.ConclusionsPatients with coronary stenoses had a higher RT index at the resting stage of exercise ECG. Resting ECG analyzed using HHT could be a method for the early detection of myocardial ischemia.

Application of Dual-Source CT Using Iterative Reconstruction Technology Combined with CT-FFR Parameters in the Diagnosis of Coronary Heart Disease.

In order to achieve early detection of myocardial ischemia and improve the diagnosis of coronary heart disease (CHD), it is necessary to find a convenient, non-invasive and effective examination method. This study aimed to explore the application value of dual-source computed tomography (CT) by using advanced modeled iterative reconstruction (ADMIRE) combined with computed tomography-fractional flow reserve (CT-FFR) technique in CHD, which provides imaging basis for early diagnosis of CHD and myocardial ischemia. Seventy-five CHD patients were examined by coronary computed tomography angiography (CCTA). Their CCTA images were reconstructed by iterative algorithm in ADMIRE 1-5 using post-processing workstation. The standard deviation (SD), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of proximal vascular images in right coronary artery (RCA), left main coronary artery (LM), left anterior descending artery (LAD) and left circumflex artery (LCX) were analyzed and compared. Invasive coronary angiography (ICA) was adopted in patients with ≥50% stenosis of coronary artery diameter. Taking ICA as the gold-standard method to accurately assess coronary arterial stenosis degree, the diagnostic efficiency of dual-source CT to diagnose coronary artery stenosis was analyzed. Some patients were subjected to myocardial CT perfusion (CTP) scanning and CT-FFR analysis, which facilitated analyzing the correlation and consistency between the diagnostic results of CTP and analysis results of CT-FFR. There was no statistical difference in the CT values of RCA, LM, LAD and LCX in groups with different ADMIRE reconstruction intensities (p > 0.05). But the noise, SNR and CNR interval were different among the iterative intensity groups (p < 0.05). Kappa consistency analysis was used to analyze the subjective evaluation results of image quality under different iterative reconstruction grades. The independent sample t-test performed on the subjective scores revealed that the scores on images were the best at ADMIRE 4. CCTA has sensitivity, specificity, positive predictive value, and negative predictive value of 91.52%, 97.59%, 97.98%, and 96.42% for identifying coronary artery stenosis, respectively. The diagnostic efficacy of CT-FFR, the Kappa analysis of myocardial CTP and CT-FFR results, which yields a Kappa value of 0.830 (p < 0.05). Spearman correlation analysis was used to statistically analyze the results of myocardial CTP and CT-FFR (correlation coefficient r = 0.774, p < 0.05). Diagnostic sensitivity and specificity were 93% and 95%, respectively. The dual-source CT using ADMIRE iterative algorithm has the best display of coronary vessels and higher image quality when the intensity is 4, and CT-FFR can be used as a non-invasive method for early detection of myocardial ischemia, which is worthy of clinical application.

Abstract 13079: Reduced Apoj-Glyc Serum Levels Identify Patients With Cardiac Ischemic Events Among Those Attending the Emergency Department With Chest Pain

Introduction: Glycosylated apolipoprotein J (ApoJ-Glyc) has been suggested to be a marker for the early detection of myocardial ischemia. Ischemia induces an intracellular accumulation of non-glycosylated ApoJ that mirrors a reduction in ApoJ-Glyc serum concentration in acute ischemic syndromes. Objective: The EDICA clinical trial - multi-centre, international, diagnostic study (NCT04119882)- was carried out to assess the performance of ApoJ-Glyc as a biomarker for the early detection of myocardial ischemia in patients attending the A&amp;E department with chest pain suggestive of acute coronary syndrome (ACS). Methods: EDICA assessed 404 patients. Blood samples were obtained on admission, for assessment of high sensitivity-troponin (hs-Tn) and ApoJ-Glyc. ApoJ-Glyc serum levels were analyzed with a novel ELISA, targeting a specific glycosylated variant of ApoJ (ApoJ-GlycA6). Results: Based on clinical diagnostic tests, 291 patients were given a final diagnosis of “non-ischemic” event and 113 patients were considered to have had an ischemic event (33 STEMI, 48 NSTEMI, 27 Unstable Angina and 5 “unclassifiable” ACS). ApoJ-GlycA6 levels were significantly lower on admission in ischemic patients, compared with non-ischemic patients (66 [46-90] vs. 73 [56-95] μg/ml, respectively; P=0.04). Ischemic patients who underwent PCI and had a pre-PCI TIMI 0-2 flow showed significantly lower ApoJ-GlycA6 levels at admission compared with non-ischemic patients (64 [37-81] vs. 73 [56-95] μg/ml; P=0.01). Of interest, 51% of ischemic patients, had “inconclusive” or negative hs-Tn at admission. Among these, ApoJ-GlycA6 identified the ischemic event in 48% (&lt;66 μg/ml). Conclusions: ApoJ-Glyc concentration decreased in patients with documented myocardial ischemia, compared with patients with a final diagnosis of “non-ischaemic” event. Patients with reduced TIMI flow indicative of poorer myocardial perfusion were among those with the lowest ApoJ-Glyc concentration. ApoJ-Glyc was low in ischemic patients irrespective of hs-Tn concentration. The results confirm the potential role of ApoJ-Glyc as a biomarker for the early detection of cardiac ischemia that could provide complementary information to that afforded by current biomarkers and diagnostic tests.

Abstract 13104: Prognostic Value of a Progressive Decrease in Apoj-Glyc Levels in Patients Attending A&amp;E Departments With Suspected Acute Coronary Syndrome or Angina-Like Pain

Introduction: Reduced serum levels of glycosylated apolipoprotein J (ApoJ-Glyc) have been proposed as a marker for the early detection of myocardial ischemia with a potential prognostic value. Objective: The EDICA clinical trial assessed the performance of ApoJ-Glyc as a biomarker for the early detection of myocardial ischemia in patients attending the A&amp;E department with chest pain suggestive of acute coronary syndrome (ACS) and investigated -as a secondary pilot objective- its prognostic value. Methods: EDICA -a multi-centre, international, diagnostic study (NCT04119882) assessed 404 patients. Based on clinical variables and diagnostic tests, 291 patients were considered to have had a “non-ischemic” event and 113 an “ischemic” event. Blood samples were obtained for the assessment of high-sensitivity troponin and ApoJ-Glyc at admission and at 1h and 3h thereafter. GRACE Risk Score was calculated in all ischemic patients. Patients were followed up for 6 months after presentation and the occurrence of MACE (cardiac death, recovered cardiac arrest, re-infarction, cardiac failure, new admission for ACS after discharge, or unplanned revascularization for cardiac ischemia after discharge) was recorded. ApoJ-Glyc serum levels were analyzed with a novel ELISA targeting a specific glycosylated variant of ApoJ (ApoJ-GlycA2). Results: Among the patients in the ischemic group, 8.8% had MACE at 6-months and these showed a 26% mean reduction in ApoJ-GlycA2 levels 3h post-admission compared with levels at presentation. This reduction was not observed in patients without MACE. Patients in the highest GRACE Risk Score tertile (&gt;118 points) showed a progressive decrease in ApoJ-GlycA2 levels after presentation compared with patients in the lower risk tertiles (mean decrease: 41% at 1h, P=0.01 and 35% at 3h, P=0.02 when compared with admission levels). Conclusions: A progressive decrease in ApoJ-Glyc levels after A&amp;E admission appears to not only identify patients with ischemic events but also those at higher risk of suffering serious recurrent cardiovascular events at 6-months’ follow-up. Further studies in larger cohorts of patients are warranted to validate the potential role of ApoJ-Glyc in risk stratification in the context of cardiac ischemic events.

ApoJ-Glyc, an early marker of myocardial ischaemia, rapidly maps improved myocardial perfusion in STEMI patients undergoing successful primary PCI

Abstract Background Previous studies using experimental models and clinical retrospective samples have pointed to a potential role of glycosylated apolipoprotein J (ApoJ-Glyc) as a marker for the early detection of myocardial ischaemia. Ischaemia induces intracellular accumulation of non-glycosylated ApoJ that mirrors the reduction in ApoJ-Glyc serum levels in patients presenting with ST-segment elevation myocardial infarction (STEMI). Purpose The EDICA (Early Detection of Myocardial Ischaemia in Suspected Acute Coronary Syndromes by Apo J-Glyc as a Novel Pathologically based Ischaemia Biomarker) clinical trial assessed the performance of ApoJ-Glyc as a biomarker for the early detection of myocardial ischaemia in patients attending the A&amp;E department with chest pain suggestive of acute coronary syndrome. Here, we report the observed changes in ApoJ-Glyc concentration in STEMI patients at baseline and after primary percutaneous coronary intervention (PPCI). Methods The EDICA trial, a multi-centre (10 sites), international, in vitro diagnostic study, assessed 404 patients attending the A&amp;E department with suspected ACS. Of these, 291 patients had a final diagnosis of “non-ischaemic” event and 113 of “ischaemic” event. The main inclusion criterion was chest pain of suspected cardiac origin. Blood samples were obtained for the simultaneous assessment of high sensitivity-troponin and ApoJ-Glyc on admission (time 0) and at 1h and 3h thereafter. Two different glycosylated variants of ApoJ (ApoJ-GlycA2 and ApoJ-GlycA6) were analyzed with a novel ELISA in serum samples. Of the “ischaemic” patients, 33 had STEMI, of whom 85% underwent PPCI. Results As expected, in the presence of myocardial ischaemia, time 0 ApoJ-GlycA2 and ApoJ-GlycA6 serum levels decreased by 34% and 48%, respectively in STEMI patients, compared with non-ischaemic patients, i.e. ApoJ-GlycA2 in STEMI: 66 [52–95] μg/ml vs. non-ischaemic: 100 [72–131] μg/ml; P=0.0002; ApoJ-GlycA6 STEMI: 38 [34–67] vs. non-ischaemic: 73 [56–95] μg/ml; P&amp;lt;0.0001. ApoJ-GlycA6 showed a discriminating ability for the presence of STEMI with a 67% sensitivity and a 83% specificity (AUC=0.747, cut-off of 50μg/ml). In STEMI patients in whom PPCI successfully restored TIMI 3 flow, ApoJ-Glyc levels increased rapidly and significantly compared with time 0 levels (ApoJ-GlycA2: P=0.02 and P=0.003 for 1h and 3h; ApoJ-GlycA6: P=0.02 and P=0.002 for 1h and 3h) and compared to patients in whom PPCI was not performed (Table 1). Conclusions ApoJ-Glyc concentrations are reduced in STEMI patients on admission and increase rapidly after improved perfusion with PPCI, pointing to a potential role of this biomarker in the early detection of reversible ischaemia and the mapping of reversible changes. The mechanisms whereby ApoJ-Glyc levels rapidly and markedly increase after PPCI are speculative at present and deserve further investigation, together with the potential prognostic value of ApoJ-Glyc in this setting. Funding Acknowledgement Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Commission 2020-EIC-SMEInstrument Phase 2; Spanish Ministry of Science, Innovation and Universities

Early detection of myocardial ischemia in 12‐lead ECG using deterministic learning and ensemble learning

Background and objective: Early detection of myocardial ischemia is a necessary but difficult problem in cardiovascular diseases. Approaches that exclusively rely on classical ST and T wave changes on the standard 12-lead electrocardiogram (ECG) lack sufficient accuracy in detecting myocardial ischemia. This study aims to construct generalizable models for the detection of myocardial ischemia in patients with subtle ECG waveform changes (namely non-diagnostic ECG) using ensemble learning to integrate ECG dynamic features acquired via deterministic learning. Methods: First, cardiodynamicsgram (CDG), a noninvasive spatiotemporal electrocardiographic method, is generated through dynamic modeling of ECG signals using the deterministic learning algorithm. Then, the spectral fitting exponent, Lyapunov exponent, and Lempel-Ziv complexity are extracted from CDG. Subsequently, the bagging-based heterogeneous ensemble algorithm is applied on CDG features to generate diverse base classifiers and aggregate them with weighted voting to obtain an ensemble model for myocardial ischemia detection. Finally, we train and test the proposed heterogeneous ensemble model on a real-world clinical dataset. This dataset consists of 499 non-diagnostic 12-lead ECG records from 499 patients collected from three independent medical centers, including 383 patients with myocardial ischemia and 116 patients without ischemia. Results: With 10-times 5-fold cross-validation technology, our proposed method achieves an average accuracy of 89.10%, sensitivity of 91.72%, and specificity of 82.69% using the heterogeneous ensemble algorithm on the real-world clinical dataset. On three independent medical centers, our ensemble model also achieves accuracy performance over 82% for patients with non-diagnostic ECG. Furthermore, our ensemble model trained with real-world clinical data yields promising results of 91.11% accuracy, 90.49% sensitivity, and 92.88% specificity on the external test set of the public PTB dataset. Conclusion: The experimental results demonstrate that the proposed model combining ensemble learning and deterministic learning presents excellent diagnostic accuracy and generalization in clinical practice, and could be implemented as a complement to the standard ECG in the clinical diagnosis of myocardial ischemia.

Myocardial Ischemia During Off-Pump Coronary Artery Bypass Grafting – A Clinical Study

Objective: To evaluate relation among trans-esophageal echocardiography (TEE), biochemical and hemodynamic parameters which could possibly help in early detection of myocardial ischemia. Design: Prospective observational, single centre study. Participants: Patients diagnosed with coronary artery triple vessel disease undergoing Off-pump Coronary Artery Bypass Grafting (OPCAB). Results: Statistically significant changes in Coronary Sinus (CS) pH and lactate levels were observed during lateral wall grafting, as well as the highest proportion of new regional wall motion abnormalities observed which signify the presence of a substantial level of myocardial ischemia during this time. We found a significant rise in HR (Heart Rate) as well as CS lactate following lateral wall grafting which correlated with the other parameters indicating substantial ischemia occurring during grafting of that territory. Maximum lactate clearance was found during anterior wall grafting and minimum after inferior wall grafting. This signifies that maximum lactate accumulates after anterior wall grafting, signifying greater extent of myocardial ischemia. Statistically significant rise in (CVP/RAP) (central venous pressure, right atrial pressure was noted) during grafting of all coronary territories, but the maximal rise was seen at the end of lateral wall grafting, followed by grafting of posterior basal wall. Conclusions: Biochemical changes in form of rise in lactate and fall in CS pH doesn’t occur in absence of obvious hemodynamic derangements. Therefore, it is difficult to detect myocardial ischemia before any hemodynamic instability.

Speckle tracking stress echocardiography: A valuable diagnostic technique or a burden for everyday practice?

Non-invasive screening for early diagnosis of coronary artery disease (CAD) represents a key element in the never-ending challenge to reduce cardiac death. Stress/rest electrocardiogram often lacks diagnostic accuracy, especially in asymptomatic patients, in fact the latest guidelines for the diagnosis and management of chronic coronary syndromes (CCS) stated the superiority of functional imaging techniques for the detection of subtle myocardial ischemia and the evaluation of myocardial viability (MV). Stress echocardiography is the most accessible and inexpensive imaging method for the study of CAD, either with pharmacological or with exercise provocative stress, based on visual wall-motion assessment. However, in some cases, such as small coronary lesions or microvascular angina, it loses its diagnostic power, therefore requiring a more sensitive approach. Accordingly, in the last years many authors investigated the possible additive value provided by the integration of an advanced but easy-to-obtain technique, that is speckle tracking imaging, to stress echocardiography, reaching promising results; nevertheless, its use is not included in the latest recommendations for CCS. The present review discusses the potential benefits from using a combination of speckle tracking and stress echocardiography for the early detection of myocardial ischemia and the assessment of MV and its suitability in different clinical scenarios, basing on the available evidence.

Application of Deep Learning Algorithm in Clinical Analysis of Patients With Serum Electrolyte Disturbance

This article analyzes the serum electrolyte disturbances of patients through deep learning algorithms. Among the 104 patients with electrolyte disturbances, 6 cases of serum potassium, sodium, chloride, calcium, phosphorus, and magnesium electrolyte disturbances have occurred, the proportion of occurrence The order is sodium > chlorine > calcium > potassium > phosphorus > magnesium. This paper proposes a deep learning algorithm for serum electrolyte disorder, and analyzes and implements the functions at various levels according to the characteristics of the Hadoop framework. The system includes electronic medical records shared storage, distributed realization of definite learning algorithms, classification and recognition of myocardial ischemia by deep learning, and Web system assisting doctor diagnosis, which lays the foundation for the construction of serum electrolyte disorder scientific research data center. In order to explore this relationship, without artificially extracting features, a deep learning model of convolution and long-term and short-term memory circulation neural network cascade was proposed to determine the positive or negative myocardial ischemia by classifying serum disorders. Conduct clinical experiments, including patients with suspected coronary heart disease and coronary angiography as the research object, taking coronary angiography results as the detection standard. Experimental results show that the model has an accuracy of 89.0% for detecting myocardial ischemia, a sensitivity of 91.7%, and a specificity of 81.5%. A linear combination model of CNN and LSTM is proposed to classify and recognize serum electrolyte disorders. Determine the learning theory to dynamically model the ST-T segment in the ECG to obtain serum electrolyte disturbance, which more vividly shows the changes in electrical information under myocardial ischemia. In order to reveal the relationship between serum electrolyte disturbance and myocardial ischemia, this paper builds a neural network model to learn and train serum electrolyte disturbance data to realize the classification of positive or negative myocardial ischemia. Tests on serum electrolyte disturbance data collected in clinical experiments show that this model can better achieve early detection of myocardial ischemia.

The Cardiodynamicsgram Based Early Detection of Myocardial Ischemia Using the Lempel-Ziv Complexity

Background: Electrocardiogram (ECG) is a routine method for detecting myocardial ischemia in clinical practice, but more than half of ECGs are without specific ischemic changes. Cardiodynamicsgram (CDG) is an effective method to detect ischemia with non-diagnostic ECG. The Lyapunov exponent (LYE) and the Fourier transform coefficient are combined to characterize the spatial and temporal features of CDG. However, in some cases, the Lyapunov exponent does not accurately enough describe the degree of irregular morphology of CDG for ischemic patients. In this context, this study aims to improve the characterization of CDG using the Lempel-Ziv (LZ) complexity instead of the Lyapunov exponent. Methods: The cardiodynamics information inside ECG is extracted via deterministic learning from the ST-T segments of ECG and then the CDG is generated by plotting the extracted three-dimensional cardiodynamics information. The Lyapunov exponent and LZ complexity are calculated from CDG and coupled with the Fourier transform coefficient respectively to construct the LYE model and LZ model for detecting myocardial ischemia. Results: 393 subjects presenting non-diagnostic ECG are enrolled in the study. 312 of them are ischemic patients selected as the myocardial ischemia group, and the other 81 non-ischemic subjects are selected as the healthy control group. The average sensitivity, specificity, and accuracy of the LYE model and the LZ model are 90.7% vs 93.4%, 86.4% vs 86.8%, and 89.0% vs 90.8%, respectively. Meanwhile, the proposed method achieves better performance on the PTB database than most of the previous studies in detecting ischemia or infarction. Conclusion: The results indicate that LZ complexity can accurately characterize the cases that cannot be accurately depicted by Lyapunov exponent, and the corresponding model is more accurate for the early detection of myocardial ischemia.

Early Detection of Myocardial Ischaemia in Suspected Acute Coronary Syndromes by Apo J-Glyc

Early Detection of Myocardial Ischaemia in Suspected Acute Coronary Syndromes by Apo J-Glyc

Sequence and time course of depletion of cardiac cellular proteins and accumulation of plasma proteins in rat early ischemic myocardium.

In order to investigate the sequence and time course of fibronectin (Fn), fibrinogen (Fg), complement (C5), myoglobin (Mb), actin (HHF35), and desmin (Dm) for the diagnosis of early myocardial ischemia, the myocardial ischemia model was established in rats, the positive reaction areas of Fn, Fg and C5 and the depletion areas of Mb, HHF35 and Dm in the ischemic cardiomyocytes were studied with immunohistochemistry, image analysis technique and statistical system. The results showed that the depletion of Dm, HHF35 and Mb, and the positive staining of Fg and C5 in ischemic cardiomyocytes were found as early as 15 min after the myocardial ischemia, but the positive staining of Fn occurred till 3 h after myocardial ischemia. With the prolongation of ischemia, the areas of the depletion of Dm, HHF35, Mb and the positive staining of Fg, C5 and Fn gradually enlarged. It is suggested that all the six immunohistochemical markers are more sensitive than routine H&E staining, and that Dm, HHF35, Mb, Fg, C5 are more sensitive markers than Fn for detection of early myocardial ischemia.

Molecular tissue changes in early myocardial ischemia: from pathophysiology to the identification of new diagnostic markers.

Diagnosing early myocardial ischemia (the initial 4 to 6h after interruption of blood flow to part of the myocardium) remains a challenge for clinical and forensic pathologists. Several immunohistochemical markers have been proposed for improving postmortem detection of early myocardial ischemia; however, no single marker appears to be both sufficiently specific as well as sensitive. This review summarizes the diverse categories of molecular tissue markers that have been investigated in human autopsy samples with acute myocardial infarction as well as in the well-established and widely used in vivo animal model of early myocardial ischemia (permanent ligation of the coronary artery). Recently identified markers appearing during the initial 2h of myocardial ischemia are highlighted. Among them, only six were tested for specificity (C5b-9, hypoxia-inducible factor 1-alpha, vascular endothelial growth factor, heart fatty acid binding protein, connexin 43, and JunB). Despite the discovery of several potentially promising markers (in terms of early expression and specificity), many of them remain to be tested and validated for application in routine diagnostics in clinical and forensic pathology. In particular, research investigating the postmortem stability of these markers is required before any might be implemented into routine diagnostics. Establishing a standardized panel of immunohistochemical markers may be more useful for improving sensitivity and specificity than searching for a single marker.