Recent advances in the diagnosis and treatment of acute myocardial infarction

Cardioprotective effect of Robinin ameliorates Endoplasmic Reticulum Stress and Apoptosis in H9c2 cells

Robinin is one of the glycosyloxyflavones that has been less explored for its therapeutic application, especially in the field of CVD. Herein, we explored the cardioprotective efficacy of Robinin by using H2O2 and Doxorubicin (DOX) - treated H9c2 cells as an in vitro model. H2O2 and DOX treatment resulted in severe cellular damage to the cardiomyocytes, which was followed by apoptosis. Apoptosis and nuclear morphology were analysed through Hoechst 33342 and AO/EB staining. qPCR was employed to detect the expression of apoptosis as well as ERS-related markers. Reactive oxygen species (ROS) generation was observed using DCFH-DA staining and FACS analysis. Signaling pathways involved were analysed using Western blot. Robinin pre-treatment considerably decreased the apoptotic rate by boosting the endogenous anti-oxidative activity and lowering the activity of Malonaldehyde and Lactate dehydrogenase enzyme. Robinin also inhibited the generation of ROS. Robinin reduced the expression of ERS-associated genes and proteins, thereby decreasing apoptosis-related proteins. Upon comparing the cardioprotective effect of Robinin with a known cardioprotective agent Dexrazoxane (DEX) it was revealed that DEX has more cardioprotective effect against DOX than H2O2-induced stress, while Robinin showed a significant protective effect against both H2O2 and DOX induced stress.

Metformin's cardioprotective role in isoprenaline-induced myocardial infarction: Unveiling insights into the AMPK, NF-κB, JAK2/STAT3 pathways, and cholinergic regulation

AIM

Despite advancements in treatment modalities, myocardial infarction (MI) remains a significant global cause of mortality and morbidity. Metformin (MET), a commonly used antidiabetic medication, has demonstrated potential in various cardioprotective mechanisms. This study investigated whether MET could alleviate the histopathological, electrocardiographic, and molecular consequences of MI in rats.

MATERIALS AND METHODS

The study hypothesis was tested using an isoprenaline (ISOP)-induced MI model, where male Wistar rats were injected with ISOP (85 mg/kg/day, s.c., for 2 days) and treated with MET at the doses of 500 and 1000 mg/kg/day for 18 days or left untreated.

KEY FINDINGS

ISOP-treated rats exhibited several indicators of MI, including significant ST-segment depression and prolonged QT-intervals on ECGs, worsened left ventricular histopathology with increased inflammatory cell infiltration, reduced expression of cardiac CHRM2, a cardioprotective cholinergic receptor, adaptive increases in AMPK and α7nAchR levels, and elevated levels of iNOS, NO, STAT3, JAK2, IL-6, TNF-α, and NF-κB. These effects were attenuated in rats treated with either low or high doses of MET. MET administration restored normal ECG recordings, diminished oxidative stress and inflammatory mediators, and downregulated NF-κB expression. Moreover, MET improved CHRM2 expression and normalized α7nAchR levels. Additionally, MET influenced the expression of key signaling molecules such as Akt, STAT3, and JAK2.

SIGNIFICANCE

These findings might suggest that MET exerts cardioprotective effects in ISOP-induced MI in rats by mitigating critical inflammatory signaling pathways and regulating protective cholinergic mechanisms in the heart.

Effects of Sacubitril/Valsartan on cardiac function, blood biochemistry and clinical efficacy in early ventricular remodeling after acute myocardial infarction

Ventricular remodeling (VR) after acute ST-elevation myocardial infarction (STEMI) is an important predictor for medium- and long-term prognosis. This study focuses on the relevant indexes of VR in patients with AMI, in which, the intervention effects of sacubitril/valsartan and enalapril were compared, guiding the clinical treatment. 58 patients with acute STEMI treated with PCI were divided into research group and control group. UCG was performed at 1 week, 1 month and 3 months after MI, and the patients' indexes were collected to compare VR and adverse reactions in the two groups. The test results showed that there was no statistical difference in the baseline data of patients in the two groups, which were comparable. In the blood biochemical index examination, no statistical difference was found in cTnI and NT-proBNP between the two groups. At 1 week after operation, the levels of cTnI and NT-proBNP in research group were lower than those in the control group. In ECG examination, there was no statistical significance in the levels of LVEF, LVEDD and LVESD at admission between the two groups. After 1 week, the results of LVEF, LVEDD, LVESD in the research group were higher than those in the control group. The results of this study show that sacubitril/valsartan can be used in patients with AMI instead of enalapril. Sacubitril/valsartan improves cardiac function in patients with emergency percutaneous coronary intervention (PCI) for AMI, inhibits ventricular remodeling, and has a low incidence of adverse cardiac events and adverse drug reactions.

Exercise mediates myocardial infarction via non-coding RNAs

Myocardial infarction (MI), a widespread cardiovascular issue, mainly occurs due to blood clot formation in the coronary arteries, which reduces blood flow to the heart muscle and leads to cell death. Incorporating exercise into a lifestyle can significantly benefit recovery and reduce the risk of future cardiac events for MI patients. Non-coding RNAs (ncRNAs) play various roles in the effects of exercise on myocardial infarction (MI). ncRNAs regulate gene expression, influence cardiac remodeling, angiogenesis, inflammation, oxidative stress, apoptosis, cardioprotection, and cardiac electrophysiology. The expression of specific ncRNAs is altered by exercise, leading to beneficial changes in heart structure, function, and recovery after MI. These ncRNAs modulate molecular pathways that contribute to improved cardiac health, including reducing inflammation, enhancing angiogenesis, promoting cell survival, and mitigating oxidative stress. Furthermore, they are involved in regulating changes in cardiac remodeling, such as hypertrophy and fibrosis, and can influence the electrical properties of the heart, thereby decreasing the risk of arrhythmias. Knowledge on MI has entered a new phase, with investigations of ncRNAs in physical exercise yielding invaluable insights into the impact of this therapeutic modality. This review compiled research on ncRNAs in MI, with an emphasis on their applicability to physical activity.

Phytoconstituents with cardioprotective properties: A pharmacological overview on their efficacy against myocardial infarction

Myocardial infarction (MI) is considered one of the most common cardiac diseases and major cause of death worldwide. The prevalence of MI and MI-associated mortality have been increasing in recent years due to poor lifestyle habits viz. residency, obesity, stress, and pollution. Synthetic drugs for the treatment of MI provide good chance of survival; however, the demand to search more safe, effective, and natural drugs is increasing. Plants provide fruitful sources for powerful antioxidant and anti-inflammatory agents for prevention and/or treatment of MI. However, many plant extracts lack exact information about their possible dosage, toxicity and drug interactions which may hinder their usefulness as potential treatment options. Phytoconstituents play cardioprotective role by either acting as a prophylactic or adjuvant therapy to the concurrently used synthetic drugs to decrease the dosage or relief the side effects of such drugs. This review highlights the role of different herbal formulations, examples of plant extracts and types of several isolated phytoconstituents (phenolic acids, flavonoids, stilbenes, alkaloids, phenyl propanoids) in the prevention of MI with reported activities. Moreover, their possible mechanisms of action are also discussed to guide future research for the development of safer substitutes to manage MI.

Investigation of the cardioprotective effects of Momordica charantia in the isoproterenol-induced myocardial infarction model in rats

BACKGROUND

Cardiovascular diseases are the most prevalent and primary cause of death globally, and the most deadly and dangerous of these diseases is myocardial infarction (MI), commonly known as heart attack, which develops due to insufficient coronary artery flow and causes irreversible myocardial cell damage. This study aimed to investigate the cardioprotective effects of Momordica charantia (MC), known for its antioxidant and anti-inflammatory properties, in an experimental acute MI model induced by isoprenaline (ISO) in rats.

METHODS

In the study, forty-nine male Wistar rats were split up into 7 groups as control (CONT), Glycerin (GLCN), isoprenaline (ISO), 500 mg/kg MC (MC500), isoprenaline+100 mg/kg MC (ISO+MC100), isoprenaline+250 mg/kg MC (ISO+MC250), isoprenaline+500 mg/kg MC (ISO+MC500). Substances were administered to the groups for 30 days. Isoprenaline (85 mg/kg) was administered by subcutaneous injection on the last two days of the study (days of the 29 and 30). Electrocardiogram (ECG) recording and collecting blood samples of the animals were performed 24 hours after the last administration of the substances under the anesthesia. Serum IL-6, Nrf2, IL-10, HO-1, TNF-α, CK-MB, cTn-I and CRP levels were determined by the ELISA method.

RESULTS

Compared to the ISO group, levels of CK-MB, HO-1, TNF-α, CRP, IL-6 and cTn-I were found statistically lower in MC-administered groups (p<0.05). In addition, MC restored ISO-induced abnormal ECG changes to normal levels.

CONCLUSION

In conclusion, ECG findings, proinflammatory, anti-inflammatory, antioxidative and cardiac biomarkers suggest that MC may have cardioprotective properties.

Mortality and Discharge Outcome in Acute Myocardial Infarction Patients: A Study Based on Korean National Hospital Discharge In-Depth Injury Survey Data

Purpose

The aim of this study was to analyze hospital-discharged acute myocardial infarction (AMI) patients in Korea (2006-2020) to understand how pre-existing conditions affect mortality rates.

Participants and Methods

This study utilized the 2006-2020 Korean National Hospital Discharge In-depth Injury Survey data. A weighted frequency analysis estimated discharged AMI patients and calculated age-standardized discharge and mortality rates, Charlson Comorbidity Index (CCI) score distribution, and general patient characteristics. Weighted logistic regression analysis examined influencing mortality factors.

Results

There were 486,464 AMI patients (143,751 female), with AMI-related mortality rates at 7.5% (36,312): 5.7% for males (19,190) and 11.8% for females (17,122). The highest mortality rate was among individuals aged 70-79 years (25%). Factors influencing mortality included sex, insurance type, admission route, hospital bed count, region, operation status, and CCI score. Mortality risk at discharge was 1.151 times higher in females than males (95% CI: 1.002-1.322), 0.787 times lower among those with national health insurance than Medicaid recipients (95% CI 0.64-0.967), 2.182 times higher among those admitted via the emergency department than the outpatient department (95% CI 1.747-2.725), and 3.402 times higher in patients with a CCI score of 3 points than those with 0 points (95% CI 1.263-9.162).

Conclusion

The number of discharged AMI patients and related mortality rates increased, underscoring the need for proactive management of chronic diseases, particularly for those with higher CCI scores.

Predictors of prolonged hospital stay and in-hospital mortality in female patients with acute myocardial infarction with specific reference to diabetes

This study aimed to determine predictors of prolonged length of stay (LOS) and mortality in female STEMI patients with diabetes in comparison to female STEMI patients without diabetes. This retrospective single-center study was conducted between 2015 and 2020 as part of the STEMI registry in our center and included all STEMI patients. RESULTS: Out of 3081 STEMI patients, 16% (N = 498) were female, and 64% (n = 318) of them had diabetes. Diabetic patients were less commonly presented with anterior wall myocardial infarction (AWMI) (47% vs 65%, p = 0.001), but tended to have a higher prevalence of left main (LM) significant disease compared to non-diabetic patients (4% vs 1%, p = 0.06). Of the patients, 36% had prolonged LOS (≥5 days), and they were more obese with a higher incidence of hemoglobin drop ≥ 3 g/dL, higher admission troponin, and peak creatinine. 22% of patients with prolonged LOS came to the hospital after receiving lytic therapy and showed a higher prevalence of multivessel stenosis. Prolonged LOS patients had a higher incidence of pulmonary edema and cardiac arrest, which necessitated ventilation, although they did not show a significant difference in mortality from the group with LOS < 5 days. Our study found a significant negative correlation between glycosylated hemoglobin (HbA1c) and left ventricular ejection fraction (LVEF) (p = 0.02), but a positive correlation was noticed between HbA1c and LOS (p < 0.001). Regression analysis showed that diabetes mellitus, hemoglobin drop, creatinine level, and LVEF were significant predictors of prolonged LOS among females, although HbA1c, BMI ≥ 30, STEMI type, and peak creatinine level were independent predictors of prolonged LOS among female diabetic patients. Age ≥ 65 years and LVEF were significant independent predictors of mortality (p = 0.04, 0.02 respectively) in STEMI female patients. CONCLUSIONS: Diabetes mellitus, bleeding, renal impairment, and LVEF were found to be significant independent predictors of prolonged LOS among STEMI females. Age ≥ 65 years and LVEF were significant predictors of mortality among STEMI female patients.

Robotic Assisted Percutaneous Coronary Intervention: Initial Australian Experience

BACKGROUND & AIM

Robotic-assisted percutaneous coronary intervention (R-PCI) has been increasingly performed overseas. Initial observations have demonstrated its clinical efficacy and safety with additional potential benefits of more accurate lesion assessment and stent deployment, with reduced radiation exposure to operators and patients. However, data from randomised controlled trials or clinical experience from Australia are lacking.

METHODS

This was a single-centre experience of all patients undergoing R-PCI as part of the run-in phase for an upcoming randomised clinical trial (ACTRN12623000480684). All R-PCI procedures were performed using the CorPath GRX robot (Corindus Vascular Robotics, Waltham, Massachusetts, USA). Key inclusion criteria included patients with obstructive coronary disease requiring percutaneous coronary intervention. Major exclusion criteria included ST-elevation myocardial infarction, cardiogenic shock or lesions deemed unsuitable for R-PCI by the operator. Clinical success was defined as residual stenosis <30% without in-hospital major adverse cardiovascular events (MACE). Technical success was defined as the completion of the R-PCI procedure without unplanned manual conversion. Procedural characteristics were compared between early (cases 1-3) and later (cases 4-21) cases.

RESULTS

Twenty-one (21) patients with a total of 24 lesions were analysed. The mean age of patients was 66.5 years, and 66% of cases were male. Radial access was used in 18 cases (86%). Most lesions were American Heart Association/American College of Cardiology class B2/C (66%). Clinical success was achieved in 100% with manual conversion required in four cases (19%). No procedural complications or in-hospital MACE occurred. Compared to the early cases, later cases had a statistically significantly shorter fluoroscopy time (44.0mins vs 25.2mins, p<0.007), dose area product (967.3 dGy.cm2 vs 361.0dGy.cm2, p=0.01) and air kerma (2484.3mGy vs 797.4mGy, p=0.009) with no difference in contrast usage (136.7mL vs 131.4mL, p=0.88).

CONCLUSIONS

We present the first clinical experience of R-PCI in Australia using the Corindus CorPath GRX robot. We achieved clinical success in all patients and technical success in the majority of cases with no procedural complications or in-hospital MACE. With increasing operator and staff experience, cases required shorter fluoroscopy time and less radiation exposure but similar contrast usage.

Irisin protects against cardiac injury by inhibiting NLRP3 inflammasome-mediated pyroptosis during remodeling after infarction

This study aimed to explore the cardioprotective mechanism of irisin in the context of cardiac injury. Utilizing a myocardial infarction (MI) mouse model, we investigated the therapeutic potential of recombinant human irisin (rhIrisin) administered for 28 days post-infarction. The efficacy of irisin treatment was evaluated through echocardiographic assessment of cardiac function and serum analysis of myocardial injury markers. Our research provided novel insights into the impacts of irisin on the NLR Family Pyrin Domain Containing 3 (NLRP3) inflammasome activation and pyroptosis, assessed both in vivo in MI mice and in vitro in hypoxia/reoxygenation-treated H9C2 cells. Remarkably, irisin treatment significantly reduced levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), and troponin I, indicating reduced myocardial injury. Echocardiography highlighted substantial improvements in left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), and dimensions (LVIDd and LVIDs) in irisin-treated mice, underscoring enhanced cardiac function. Moreover, irisin was shown to significantly suppress the mRNA and protein expressions of key components involved in NLRP3 inflammasome pathway (NLRP3, ASC, caspase-1 (p20), and interleukin-18 (IL-18)) both in MI-induced mice and hypoxia/reoxygenation-treated cells. This study firstly reveals that the cardioprotective effect of irisin is mediated through the attenuation of NLRP3 inflammasome activation and pyroptosis, positioning irisin as a promising therapeutic agent for cardiac injury.

Detailed role of mesenchymal stem cell (MSC)-derived exosome therapy in cardiac diseases

Coronary heart disease (CHD) continues to be the leading cause of morbidity and mortality. There are numerous therapeutic reperfusion methods, including thrombolytic therapy, primary percutaneous coronary intervention, and anti-remodeling drugs like angiotensin-converting enzyme inhibitors and beta-blockers. Despite this, there is no pharmacological treatment that can effectively stop cardiomyocyte death brought on by myocardial ischemia/reperfusion (I/R) injury. For the purpose of regenerating cardiac tissue, mesenchymal stem cell (MSC) therapy has recently gained more attention. The pleiotropic effects of MSCs are instead arbitrated by the secretion of soluble paracrine factors and are unrelated to their capacity for differentiation. One of these paracrine mediators is the extracellular vesicle known as an exosome. Exosomes deliver useful cargo to recipient cells from MSCs, including peptides, proteins, cytokines, lipids, miRNA, and mRNA molecules. Exosomes take part in intercellular communication processes and help tissues and organs that have been injured or are ill heal. Exosomes alone were found to be the cause of MSCs' therapeutic effects in a variety of animal models, according to studies. Here, we have focused on the recent development in the therapeutic capabilities of exosomal MSCs in cardiac diseases.

Data analytics approach for short- and long-term mortality prediction following acute non-ST-elevation myocardial infarction (NSTEMI) and Unstable Angina (UA) in Asians

BACKGROUND

Traditional risk assessment tools often lack accuracy when predicting the short- and long-term mortality following a non-ST-segment elevation myocardial infarction (NSTEMI) or Unstable Angina (UA) in specific population.

OBJECTIVE

To employ machine learning (ML) and stacked ensemble learning (EL) methods in predicting short- and long-term mortality in Asian patients diagnosed with NSTEMI/UA and to identify the associated features, subsequently evaluating these findings against established risk scores.

METHODS

We analyzed data from the National Cardiovascular Disease Database for Malaysia (2006-2019), representing a diverse NSTEMI/UA Asian cohort. Algorithm development utilized in-hospital records of 9,518 patients, 30-day data from 7,133 patients, and 1-year data from 7,031 patients. This study utilized 39 features, including demographic, cardiovascular risk, medication, and clinical features. In the development of the stacked EL model, four base learner algorithms were employed: eXtreme Gradient Boosting (XGB), Support Vector Machine (SVM), Naive Bayes (NB), and Random Forest (RF), with the Generalized Linear Model (GLM) serving as the meta learner. Significant features were chosen and ranked using ML feature importance with backward elimination. The predictive performance of the algorithms was assessed using the area under the curve (AUC) as a metric. Validation of the algorithms was conducted against the TIMI for NSTEMI/UA using a separate validation dataset, and the net reclassification index (NRI) was subsequently determined.

RESULTS

Using both complete and reduced features, the algorithm performance achieved an AUC ranging from 0.73 to 0.89. The top-performing ML algorithm consistently surpassed the TIMI risk score for in-hospital, 30-day, and 1-year predictions (with AUC values of 0.88, 0.88, and 0.81, respectively, all p < 0.001), while the TIMI scores registered significantly lower at 0.55, 0.54, and 0.61. This suggests the TIMI score tends to underestimate patient mortality risk. The net reclassification index (NRI) of the best ML algorithm for NSTEMI/UA patients across these periods yielded an NRI between 40-60% (p < 0.001) relative to the TIMI NSTEMI/UA risk score. Key features identified for both short- and long-term mortality included age, Killip class, heart rate, and Low-Molecular-Weight Heparin (LMWH) administration.

CONCLUSIONS

In a broad multi-ethnic population, ML approaches outperformed conventional TIMI scoring in classifying patients with NSTEMI and UA. ML allows for the precise identification of unique characteristics within individual Asian populations, improving the accuracy of mortality predictions. Continuous development, testing, and validation of these ML algorithms holds the promise of enhanced risk stratification, thereby revolutionizing future management strategies and patient outcomes.

A quadruplet 3-D laser scribed graphene/MoS2, functionalised N2-doped graphene quantum dots and lignin-based Ag-nanoparticles for biosensing

Troponin I is a protein released into the human blood circulation and a commonly used biomarker due to its sensitivity and specificity in diagnosing myocardial injury. When heart injury occurs, elevated troponin Troponin I levels are released into the bloodstream. The biomarker is a strong and reliable indicator of myocardial injury in a person, with immediate treatment required. For electrochemical sensing of Troponin I, a quadruplet 3D laser-scribed graphene/molybdenum disulphide functionalised N2-doped graphene quantum dots hybrid with lignin-based Ag-nanoparticles (3D LSG/MoS2/N-GQDs/L-Ag NPs) was fabricated using a hydrothermal process as an enhanced quadruplet substrate. Hybrid MoS2 nanoflower (H3 NF) and nanosphere (H3 NS) were formed independently by varying MoS2 precursors and were grown on 3D LSG uniformly without severe stacking and restacking issues, and characterized by morphological, physical, and structural analyses with the N-GQDs and Ag NPs evenly distributed on 3D LSG/MoS2 surface by covalent bonding. The selective capture of and specific interaction with Troponin I by the biotinylated aptamer probe on the bio-electrode, resulted in an increment in the charge transfer resistance. The limit of detection, based on impedance spectroscopy, is 100 aM for both H3 NF and H3 NS hybrids, with the H3 NF hybrid biosensor having better analytical performance in terms of linearity, selectivity, repeatability, and stability.

Role of Pericytes in Cardiomyopathy-Associated Myocardial Infarction Revealed by Multiple Single-Cell Sequencing Analysis

Acute myocardial infarction (AMI) is one of the leading causes of cardiovascular death worldwide. AMI with cardiomyopathy is accompanied by a poor long-term prognosis. However, limited studies have focused on the mechanism of cardiomyopathy associated with AMI. Pericytes are important to the microvascular function in the heart, yet little attention has been paid to their function in myocardial infarction until now. In this study, we integrated single-cell data from individuals with cardiomyopathy and myocardial infarction (MI) GWAS data to reveal the potential function of pericytes in cardiomyopathy-associated MI. We found that pericytes were concentrated in the left atrium and left ventricle tissues. DLC1/GUCY1A2/EGFLAM were the top three uniquely expressed genes in pericytes (p < 0.05). The marker genes of pericytes were enriched in renin secretion, vascular smooth muscle contraction, gap junction, purine metabolism, and diabetic cardiomyopathy pathways (p < 0.05). Among these pathways, the renin secretion and purine metabolism pathways were also found in the process of MI. In cardiomyopathy patients, the biosynthesis of collagen, modulating enzymes, and collagen formation were uniquely negatively regulated in pericytes compared to other cell types (p < 0.05). COL4A2/COL4A1/SMAD3 were the hub genes in pericyte function involved in cardiomyopathy and AMI. In conclusion, this study provides new evidence about the importance of pericytes in the pathogenesis of cardiomyopathy-associated MI. DLC1/GUCY1A2/EGFLAM were highly expressed in pericytes. The hub genes COL4A2/COL4A1/SMAD3 may be potential research targets for cardiomyopathy-associated MI.

Changes in Physical Activity and Incidence of Nonfatal Cardiovascular Events in 47 153 Survivors of Myocardial Infarction

Background The majority of patients survive the acute phase of myocardial infarction (MI) but have an increased risk of recurrent cardiovascular disease (CVD) events. To be regularly physically active or change activity level is associated with a lower risk of all-cause mortality. The objective was to explore to what extent physical activity (PA) levels or change in PA levels during the first year post-MI was associated with any recurrent nonfatal CVD events and specific CVD events (eg, MI, ischemic stroke, and vascular dementia). Methods and Results This cohort study among MI survivors was based on Swedish national registries between 2005 and 2020. PA levels were self-rated at 2 and 12 months post-MI, and patients were classified into remaining physically inactive, increasing, decreasing, or remaining active. A total of 6534 nonfatal CVD events occurred during 6 years of follow-up among the 47 153 included patients. In fully adjusted analyses, the risk of any nonfatal CVD event was lower (P<0.05) among patients remaining active (37%), increasing (22%), or decreasing (18%) PA level compared with remaining inactive. Compared with remaining inactive, the risk of recurring MI and stroke was lower (P>0.05) among remaining active (41% versus 52%, respectively), increasing (20% versus 35%, respectively), or decreasing PA level (24% versus 34%, respectively). For vascular dementia, patients remaining physically active had an 80% lower risk compared with remaining inactive (P<0.05). Conclusions Remaining physically active or change in PA levels during the first year post-MI was associated with a lower risk of recurrent nonfatal CVD events. This emphasizes the importance of supporting patients to continue to be or become physically active.

Mitigation of Fibrosis after Myocardial Infarction in Rats by Using a Porcine Cholecyst Extracellular Matrix

Fibrosis that occurs after nonfatal myocardial infarction (MI) is an irreversible reparative cardiac tissue remodeling process characterized by progressive deposition of highly cross-linked type I collagen. No currently available therapeutic strategy prevents or reverses MI-associated fibrotic scarring of myocardium. In this study, we used an epicardial graft prepared of porcine cholecystic extracellular matrix to treat experimental nonfatal MI in rats. Graft-assisted healing was characterized by reduced fibrosis, with scanty deposition of type I collagen. Histologically, the tissue response was associated with a favorable regenerative reaction predominated by CD4-positive helper T lymphocytes, enhanced angiogenesis, and infiltration of proliferating cells. These observations indicate that porcine cholecystic extracellular matrix delayed the fibrotic reaction and support its use as a potential biomaterial for mitigating fibrosis after MI. Delaying the progression of cardiac tissue remodeling may widen the therapeutic window for management of scarring after MI.

Prehospital Electrocardiogram Transmission and Prehospital Scene Time: A Retrospective Cohort Study

Background: Telemedical transmission of prehospital electrocardiograms (ECGs) to a target clinic may improve clinical workflows and speed of intervention. However, whether ECG transmission delays prehospital workflows remains controversial. Therefore, we aimed to clarify whether ECG transmission prolongs prehospital scene time in patients diagnosed with acute coronary syndrome (ACS). Methods: We retrospectively included all patients diagnosed with ACS by prehospital emergency physicians from July 2016 to June 2019 at a single academic center. The primary endpoint was the effect of ECG transmission on prehospital scene time. The secondary endpoints were the effects of ECG diagnosis on prehospital scene time and quality of care. Multivariable regression was used to account for patients' age, physician specialty, completion of specialty training, and whether emergencies occurred throughout the day or night shifts as potential confounders. Results: A total of 1,106 cases were included, of which 154 ECG transmissions were performed. ECG transmission prolonged prehospital scene time by an average of 3 min: adjusted regression coefficient [95% confidence interval (95% CI)]: 3.24 (1.7-4.8), p < 0.001. Prehospital treatment time was not influenced by prehospital ECG-based diagnosis (ST-elevation myocardial infarction [STEMI] vs. non-ST-elevation ACS [NSTE-ACS]): adjusted regression coefficient (95% CI): 0.7 (-1.3 to 2.7), p = 0.490. Emergency physicians adhered to local standard operating procedures in 739 of 1,007 (73%) patients diagnosed with NSTE-ACS and 93 of 99 (94%) patients diagnosed with STEMI. A STEMI diagnosis compared with NSTE-ACS was associated with five times higher odds of adhering to standard operating procedures (odds ratio [95% CI]: 5.6 [2.7-14.6], p < 0.001). Conclusion: The observed delay of ∼3 min in the prehospital scene time by ECG transmission is clinically irrelevant. For patients prehospitally diagnosed with NSTE-ACS who do not meet STEMI criteria, adherence to standard operating procedures seems unjustifiably low and should be improved.

Recent Advances and Challenges in Textile Electrodes for Wearable Biopotential Signal Monitoring: A Comprehensive Review

The technology of wearable medical equipment has advanced to the point where it is now possible to monitor the electrocardiogram and electromyogram comfortably at home. The transition from wet Ag/AgCl electrodes to various types of gel-free dry electrodes has made it possible to continuously and accurately monitor the biopotential signals. Fabrics or textiles, which were once meant to protect the human body, have undergone significant development and are now employed as intelligent textile materials for healthcare monitoring. The conductive textile electrodes provide the benefit of being breathable and comfortable. In recent years, there has been a significant advancement in the fabrication of wearable conductive textile electrodes for monitoring biopotential signals. This review paper provides a comprehensive overview of the advances in wearable conductive textile electrodes for biopotential signal monitoring. The paper covers various aspects of the technology, including the electrode design, various manufacturing techniques utilised to fabricate wearable smart fabrics, and performance characteristics. The advantages and limitations of various types of textile electrodes are discussed, and key challenges and future research directions are identified. This will allow them to be used to their fullest potential for signal gathering during physical activities such as running, swimming, and other exercises while being linked into wireless portable health monitoring systems.

A plasma proteomic approach in patients with heart failure after acute myocardial infarction: insights into the pathogenesis and progression of the disease

Aims

The pathogenesis of disease progression targets for patients with heart failure after acute myocardial infarction was investigated by using plasma proteomics.

Methods

The plasma proteomes of acute myocardial infarction patients with (MI-HF) and without (MI-WHF) heart failure were compared. Each group consisted of 10 patients who were matched for age and sex. The peptides were analyzed by 2-dimensional liquid chromatography coupled to tandem mass spectrometry in a high definition mode. Parallel reaction monitoring (PRM) verified the selected target proteins.

Results

We identified and quantified 2,589 and 2,222 proteins, respectively, and found 117 differentially expressed proteins (DEPs) (≥1.5-fold), when the MI-HF and MI-WHF groups were compared. Of these 51 and 66 were significantly up-regulated and down-regulated, respectively. The significant DEPs was subjected to protein-protein interaction network analysis which revealed a central role of the NF-κB signaling pathway in the MI-HF patients. PRM verified that MB, DIAPH1, VNN1, GOT2, SLC4A1, CRP, CKM, SOD3, F7, DLD, PGAM2, GOT1, UBA7 and HYOU1 were 14 proteins which were highly expressed in MI-HF patients.

Conclusions

These findings showed a group of proteins related to the NF-κB signaling pathway in the pathogenesis of patients with poor outcomes after experiencing MI-HF. These proteins may be useful candidate markers for the diagnosis of MI-HF as well as help to elucidate the pathophysiology of this major cause of mortality in older patients.

T-Wave Analysis on the 24 h Holter ECG Monitoring as a Predictive Assessment of Major Adverse Cardiovascular Events in Patients with Myocardial Infarction: A Literature Review and Future Perspectives

Myocardial ischemia is a pathophysiological state characterized by inadequate perfusion of the myocardium, resulting in an imbalance between myocardial oxygen demand and supply. It is most commonly caused by coronary artery disease, in which atherosclerotic plaques lead to luminal narrowing and reduced blood flow to the heart. Myocardial ischemia can manifest as angina pectoris or silent myocardial ischemia and can progress to myocardial infarction or heart failure if left untreated. Diagnosis of myocardial ischemia typically involves a combination of clinical evaluation, electrocardiography and imaging studies. Electrocardiographic parameters, as assessed by 24 h Holter ECG monitoring, can predict the occurrence of major adverse cardiovascular events in patients with myocardial ischemia, independent of other risk factors. The T-waves in patients with myocardial ischemia have prognostic value for predicting major adverse cardiovascular events, and their electrophysiological heterogeneity can be visualized using various techniques. Combining the electrocardiographic findings with the assessment of myocardial substrate may offer a better picture of the factors that can contribute to cardiovascular death.

A Case of Myocardial Infarction in a Patient With Spontaneous Spinal Subdural Hematoma

Spontaneous spinal subdural hematoma (SSDH) is an extremely rare clinical condition and a neurologic emergency that is most commonly associated with anticoagulation therapy and coagulopathy. We present a case of myocardial infarction (MI) with an unusually high troponin level in the setting of SSDH. This case underscores the challenges and importance of properly differentiating type 1 MI from type 2 MI as the management is different. It also presents challenges in managing MI in the setting of recent bleeding in the context of desired anticoagulation and antiplatelet therapy.

Microfluidic encapsulation of photosynthetic cyanobacteria in hydrogel microparticles augments oxygen delivery to rescue ischemic myocardium

Cardiovascular disease, primarily caused by coronary artery disease, is the leading cause of death in the United States. While standard clinical interventions have improved patient outcomes, mortality rates associated with eventual heart failure still represent a clinical challenge. Macrorevascularization techniques inadequately address the microvascular perfusion deficits that persist beyond primary and secondary interventions. In this work, we investigate a photosynthetic oxygen delivery system that rescues the myocardium following acute ischemia. Using a simple microfluidic system, we encapsulated Synechococcus elongatus into alginate hydrogel microparticles (HMPs), which photosynthetically deliver oxygen to ischemic tissue in the absence of blood flow. We demonstrate that HMPs improve the viability of S. elongatus during the injection process and allow for simple oxygen diffusion. Adult male Wistar rats (n = 45) underwent sham surgery, acute ischemia reperfusion surgery, or a chronic ischemia reperfusion surgery, followed by injection of phosphate buffered saline (PBS), S. elongatus suspended in PBS, HMPs, or S. elongatus encapsulated in HMPs. Treatment with S. elongatus-HMPs mitigated cellular apoptosis and improved left ventricular function. Thus, delivery of S. elongatus encapsulated in HMPs improves clinical translation by utilizing a minimally invasive delivery platform that improves S. elongatus viability and enhances the therapeutic benefit of a novel photosynthetic system for the treatment of myocardial ischemia.

Predictors of Mortality for Patients with ST-Elevation Myocardial Infraction after 2-Year Follow-Up: A ST-Elevation Myocardial Infarction Cohort in Isfahan Study

Background

Mortality of ST-elevation myocardial infarction (STEMI) patients is increasing in world. This study defines predictors of mortality in patients who have STEMI.

Materials and Methods

This study was a part of the ST-elevated myocardial infarction cohort study in Isfahan conducted on 876 acute myocardial infarction (MI) followed for 2 years that 781 patient entered. The effect of predictors of mortality includes demographic, physiological, and clinical characterizes compared in two groups alive and died patients. MACE was defined as nonfatal MI, nonfatal stroke, and atherosclerosis cardiovascular disease-related death was recorded. Univariate and multiple logistic regression analyses were performed. All analyses performed using SPSS 20.0. P < 0.05 considered statistically significant.

Results

A total 781 patients, 117 (13%) that 72 (8.5%) was in-hospital died. The mean (standard deviation) age of the patients was 60.92 (12.77) years and 705 (81.3%) patients were males. Significant factors that affected mortality on analysis of demographic and physiological parameters were age (P < 0.001), sex (P = 0.004), transfusion (P = 0.010), STEMI type (P < 0.001), number epicardial territories >50% (P = 0.001), ventilation options (P < 0.001), smoker (P = 0.003), and diabetes (P = 0.026). Significant clinical factors affected mortality were ejection fraction (EF) (P < 0.001), creatinine (P < 0.001), hemoglobin (P < 0.001), low-density lipoprotein-cholesterol (LDL-C) (P = 0.019), and systolic blood pressure (P < 0.001). Multiple logistics regression model definition significant predictors for mortality were age (P < 0.001), heart rate (HR) (P = 0.007), EF (0.039), LDL-C (P = 0.002), and preangia (P = 0.022).

Conclusion

The set of factors can increase or decrease mortality in these patients. Significant predictors of mortality STEMI patients by 2-year follow up were age, HR, EF, LDL-C, and preangia. It seems that more articles need to be done in different parts of Iran to confirm the results.

5mC modification patterns provide novel direction for early acute myocardial infarction detection and personalized therapy

Background

Most deaths from coronary artery disease (CAD) are due to acute myocardial infarction (AMI). There is an urgent need for early AMI detection, particularly in patients with stable CAD. 5-methylcytosine (5mC) regulatory genes have been demonstrated to involve in the progression and prognosis of cardiovascular diseases, while little research examined 5mC regulators in CAD to AMI progression.

Method

Two datasets (GSE59867 and GSE62646) were downloaded from Gene Expression Omnibus (GEO) database, and 21 m5C regulators were extracted from previous literature. Dysregulated 5mC regulators were screened out by "limma." The least absolute shrinkage and selection operator (LASSO) and support vector machine recursive feature elimination (SVM-RFE) algorithm were employed to identify hub 5mC regulators in CAD to AMI progression, and 43 clinical samples (Quantitative real-time PCR) were performed for expression validation. Then a logistic model was built to construct 5mC regulator signatures, and a series of bioinformatics algorithms were performed for model validation. Besides, 5mC-associated molecular clusters were studied via unsupervised clustering analysis, and correlation analysis between immunocyte and 5mC regulators in each cluster was conducted.

Results

Nine hub 5mC regulators were identified. A robust model was constructed, and its prominent classification accuracy was verified via ROC curve analysis (area under the curve [AUC] = 0.936 in the training cohort and AUC = 0.888 in the external validation cohort). Besides, the clinical effect of the model was validated by decision curve analysis. Then, 5mC modification clusters in AMI patients were identified, along with the immunocyte infiltration levels of each cluster. The correlation analysis found the strongest correlations were TET3-Mast cell in cluster-1 and TET3-MDSC in cluster-2.

Conclusion

Nine hub 5mC regulators (DNMT3B, MBD3, UHRF1, UHRF2, NTHL1, SMUG1, ZBTB33, TET1, and TET3) formed a diagnostic model, and concomitant results unraveled the critical impact of 5mC regulators, providing interesting epigenetics findings in AMI population vs. stable CAD.

Quo Vadis? Immunodynamics of Myeloid Cells after Myocardial Infarction

Myocardial infarction (MI), a major contributor to worldwide morbidity and mortality, is caused by a lack of blood flow to the heart. Affected heart tissue becomes ischemic due to deficiency of blood perfusion and oxygen delivery. In case sufficient blood flow cannot be timely restored, cardiac injury with necrosis occurs. The ischemic/necrotic area induces a systemic inflammatory response and hundreds of thousands of leukocytes are recruited from the blood to the injured heart. The blood pool of leukocytes is rapidly depleted and urgent re-supply of these cells is needed. Myeloid cells are generated in the bone marrow (BM) and spleen, released into the blood, travel to sites of need, extravasate and accumulate inside tissues to accomplish various functions. In this review we focus on the "leukocyte supply chain" and will separately evaluate different myeloid cell compartments (BM, spleen, blood, heart) in steady state and after MI. Moreover, we highlight the local and systemic kinetics of extracellular factors, chemokines and danger signals involved in the regulation of production/generation, release, transportation, uptake, and activation of myeloid cells during the inflammatory phase of MI.

Effective treatment of intractable diseases using nanoparticles to interfere with vascular supply and angiogenic process

Angiogenesis is a vital biological process involving blood vessels forming from pre-existing vascular systems. This process contributes to various physiological activities, including embryonic development, hair growth, ovulation, menstruation, and the repair and regeneration of damaged tissue. On the other hand, it is essential in treating a wide range of pathological diseases, such as cardiovascular and ischemic diseases, rheumatoid arthritis, malignancies, ophthalmic and retinal diseases, and other chronic conditions. These diseases and disorders are frequently treated by regulating angiogenesis by utilizing a variety of pro-angiogenic or anti-angiogenic agents or molecules by stimulating or suppressing this complicated process, respectively. Nevertheless, many traditional angiogenic therapy techniques suffer from a lack of ability to achieve the intended therapeutic impact because of various constraints. These disadvantages include limited bioavailability, drug resistance, fast elimination, increased price, nonspecificity, and adverse effects. As a result, it is an excellent time for developing various pro- and anti-angiogenic substances that might circumvent the abovementioned restrictions, followed by their efficient use in treating disorders associated with angiogenesis. In recent years, significant progress has been made in different fields of medicine and biology, including therapeutic angiogenesis. Around the world, a multitude of research groups investigated several inorganic or organic nanoparticles (NPs) that had the potential to effectively modify the angiogenesis processes by either enhancing or suppressing the process. Many studies into the processes behind NP-mediated angiogenesis are well described. In this article, we also cover the application of NPs to encourage tissue vascularization as well as their angiogenic and anti-angiogenic effects in the treatment of several disorders, including bone regeneration, peripheral vascular disease, diabetic retinopathy, ischemic stroke, rheumatoid arthritis, post-ischemic cardiovascular injury, age-related macular degeneration, diabetic retinopathy, gene delivery-based angiogenic therapy, protein delivery-based angiogenic therapy, stem cell angiogenic therapy, and diabetic retinopathy, cancer that may benefit from the behavior of the nanostructures in the vascular system throughout the body. In addition, the accompanying difficulties and potential future applications of NPs in treating angiogenesis-related diseases and antiangiogenic therapies are discussed.

Analysis of Anti-Arrhythmic Impacts of Crocin through Estimation of Expression of Cx43 in Myocardial Infarction Using a Rat Animal Model

Arrhythmia is an important cause of death after myocardial infarction (MI). Different substances have been evaluated for their anti-arrhythmic effect in MI. This study was performed to evaluate the anti-arrhythmic impacts of crocin in an MI animal model (rat) by estimation of the expression of connexin 43 (Cx43). Fifty male Sprague-Dawley rats were grouped into 5 groups, each composed of 10 rats. The first group was regarded as the normal control group and the second one was considered as the MI group, which was caused by ligation of the left anterior descending artery. The other three groups received crocin 50 or 10 mg/kg/day or metoprolol 100 mg/kg/day for 1 week, following ligation of the left anterior descending artery. Evaluated outcomes were cardiac Cx43 expression, arrhythmia incidence, histological findings, and myocyte resting potential. Crocin-treated MI groups showed a significantly lower arrhythmia score than the non-treated MI group, 10 mg/kg/day (1.85 ± 0.55, p < 0.01) and 50 mg/kg/day (1.70 ± 0.33, p < 0.01). Groups that received crocin 10 mg/kg/day (66.30 ± 2.59, p < 0.01), crocin 50 mg/kg/day (68.10 ± 2.43, p < 0.01), and metoprolol 100 mg/kg/day (-63.54 ± 0.63 mV, p < 0.01) significantly prevented depolarization in comparison with the non-treated MI group. Expression of Cx43 mRNA in crocin 10 mg/kg/day (1.54 ± 0.24, p < 0.01), crocin 50 mg/kg/day (1.73 ± 0.09, p < 0.01), and metoprolol 100 mg/kg/day (1.75 ± 0.14, p < 0.01) treatment groups was significantly higher in comparison with the non-treated MI group. Crocin showed a preventive effect on the arrhythmogenic impact of MI in an experimental model of ischemic injury through an increase in expression of Cx43.

Myocardial infarction from a tissue engineering and regenerative medicine point of view: A comprehensive review on models and treatments

In the modern world, myocardial infarction is one of the most common cardiovascular diseases, which are responsible for around 18 million deaths every year or almost 32% of all deaths. Due to the detrimental effects of COVID-19 on the cardiovascular system, this rate is expected to increase in the coming years. Although there has been some progress in myocardial infarction treatment, translating pre-clinical findings to the clinic remains a major challenge. One reason for this is the lack of reliable and human representative healthy and fibrotic cardiac tissue models that can be used to understand the fundamentals of ischemic/reperfusion injury caused by myocardial infarction and to test new drugs and therapeutic strategies. In this review, we first present an overview of the anatomy of the heart and the pathophysiology of myocardial infarction, and then discuss the recent developments on pre-clinical infarct models, focusing mainly on the engineered three-dimensional cardiac ischemic/reperfusion injury and fibrosis models developed using different engineering methods such as organoids, microfluidic devices, and bioprinted constructs. We also present the benefits and limitations of emerging and promising regenerative therapy treatments for myocardial infarction such as cell therapies, extracellular vesicles, and cardiac patches. This review aims to overview recent advances in three-dimensional engineered infarct models and current regenerative therapeutic options, which can be used as a guide for developing new models and treatment strategies.

Fabrication and Characterization of Acute Myocardial Infarction Myoglobin Biomarker Based on Chromium-Doped Zinc Oxide Nanoparticles

In this article, we describe the fabrication and characterization of a sensor for acute myocardial infarction that detects myoglobin biomarkers using chromium (Cr)-doped zinc oxide (ZnO) nanoparticles (NPs). Pure and Cr-doped ZnO NPs (13 × 10¹⁷, 20 × 10¹⁷, and 32 × 10¹⁷ atoms/cm³ in the solid phase) were synthesized by a facile low-temperature sol-gel method. Synthesized NPs were examined for structure and morphological analysis using various techniques to confirm the successful formation of ZnO NPs. Zeta potential was measured in LB media at a negative value and increased with doping. XPS spectra confirmed the presence of oxygen deficiency in the synthesized material. To fabricate the sensor, synthesized NPs were screen-printed over a pre-fabricated gold-coated working electrode for electrochemical detection of myoglobin (Mb). Cr-doped ZnO NPs doped with 13 × 10¹⁷ Cr atomic/cm³ revealed the highest sensitivity of ~37.97 μA.cm⁻²nM⁻¹ and limit of detection (LOD) of 0.15 nM for Mb with a response time of ≤10 ms. The interference study was carried out with cytochrome c (Cyt-c) due to its resemblance with Mb and human serum albumin (HSA) abundance in the blood and displayed distinct oxidation potential and current values for Mb. Cr-doped ZnO NP-based Mb biosensors showed 3 times higher sensitivity as compared to pure ZnO NP-based sensors.

Human Heart Anoxia and Reperfusion Tissue (HEART) Model for the Rapid Study of Exosome Bound miRNA Expression As Biomarkers for Myocardial Infarction

Current biomarkers for myocardial infarction (MI) diagnosis are typically late markers released upon cell death, incapable of distinguishing between ischemic and reperfusion injury and can be symptoms of other pathologies. Circulating microRNAs (miRNAs) have recently been proposed as alternative biomarkers for MI diagnosis; however, detecting the changes in the human cardiac miRNA profile during MI is extremely difficult. Here, to study the changes in miRNA levels during acute MI, a heart-on-chip model with a cardiac channel, containing human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes in human heart decellularized matrix and collagen, and a vascular channel, containing hiPSC-derived endothelial cells, is developed. This model is exposed to anoxia followed by normoxia to mimic ischemia and reperfusion, respectively. Using a highly sensitive miRNA biosensor that the authors developed, the exact same increase in miR-1, miR-208b, and miR-499 levels in the MI-on-chip and the time-matched human blood plasma samples collected before and after ischemia and reperfusion, is shown. That the surface marker profile of exosomes in the engineered model changes in response to ischemic and reperfusion injury, which can be used as biomarkers to detect MI, is also shown. Hence, the MI-on-chip model developed here can be used in biomarker discovery.

Long-term outcomes of 316 patients with STEMI following coronary stent implantation

BACKGROUND

Stent thrombosis (ST)-related ST-segment elevation myocardial infarction (STEMI) has very high mortality and poor prognosis. With the extensive construction of the chest pain center in China, the question arises as to whether these special patients will benefit.

METHODS

From January 2015 to February 2018, 316 patients with STEMI admitted to the coronary care unit (CCU) of Tianjin Chest Hospital after coronary stent implantation were enrolled in this retrospective study. All patients underwent coronary angiography. According to whether STEMI was due to ST, these patients were divided into either a ST group (n=247) or a non-ST group (n=69). The in-hospital mortality and major adverse cardiac events (MACEs), including all-cause mortality, re-ST, target vessel revascularization (TVR), and acute myocardial infarction (AMI) within the 1-year follow-up were compared between the two groups.

RESULTS

78% of cases of STEMI following coronary stent implantation were caused by ST. The in-hospital mortality of the ST group was 0.8% and that of the non-ST group was 1.4% (P>0.05). Forty-two cases had MACEs in the 1-year follow-up, with a higher incidence in the ST group compared to the non-ST group (15.4% vs. 5.8%, P=0.038). The Kaplan-Meier survival analysis showed a lower 1-year event free survival (EFS) in the ST group compared to the non-ST group (84.6% vs. 94.2%, P=0.035). Age over 80-years-old, hypertension, diabetes, hypercholesterolemia, and family history of coronary artery disease (CAD) were all independent risk factors for MACE.

CONCLUSION

ST is the leading cause of STEMI in patients following coronary stent implantation. There was no significant difference in mortality between the ST group and the non-ST group during hospitalization, with a worse prognosis in the ST group during the 1-year follow-up.

Neu3 Sialidase Activates the RISK Cardioprotective Signaling Pathway during Ischemia and Reperfusion Injury (IRI)

Coronary reperfusion strategies are life-saving approaches to restore blood flow to cardiac tissue after acute myocardial infarction (AMI). However, the sudden restoration of normal blood flow leads to ischemia and reperfusion injury (IRI), which results in cardiomyoblast death, irreversible tissue degeneration, and heart failure. The molecular mechanism of IRI is not fully understood, and there are no effective cardioprotective strategies to prevent it. In this study, we show that activation of sialidase-3, a glycohydrolytic enzyme that cleaves sialic acid residues from glycoconjugates, is cardioprotective by triggering RISK pro-survival signaling pathways. We found that overexpression of Neu3 significantly increased cardiomyoblast resistance to IRI through activation of HIF-1α and Akt/Erk signaling pathways. This raises the possibility of using Sialidase-3 activation as a cardioprotective reperfusion strategy after myocardial infarction.

Insight into the Role of the PI3K/Akt Pathway in Ischemic Injury and Post-Infarct Left Ventricular Remodeling in Normal and Diabetic Heart

Despite the significant decline in mortality, cardiovascular diseases are still the leading cause of death worldwide. Among them, myocardial infarction (MI) seems to be the most important. A further decline in the death rate may be achieved by the introduction of molecularly targeted drugs. It seems that the components of the PI3K/Akt signaling pathway are good candidates for this. The PI3K/Akt pathway plays a key role in the regulation of the growth and survival of cells, such as cardiomyocytes. In addition, it has been shown that the activation of the PI3K/Akt pathway results in the alleviation of the negative post-infarct changes in the myocardium and is impaired in the state of diabetes. In this article, the role of this pathway was described in each step of ischemia and subsequent left ventricular remodeling. In addition, we point out the most promising substances which need more investigation before introduction into clinical practice. Moreover, we present the impact of diabetes and widely used cardiac and antidiabetic drugs on the PI3K/Akt pathway and discuss the molecular mechanism of its effects on myocardial ischemia and left ventricular remodeling.

Identifying the cardioprotective mechanism of Danyu Tongmai Granules against myocardial infarction by targeted metabolomics combined with network pharmacology

BACKGROUND

Danyu Tongmai Granules (DY), the commercial Chinese medicine, was well-accepted cardiovascular protective actions in clinic. However, the mechanisms underlying the beneficial effects of DY on cardiovascular disease still need largely to be clarified.

PURPOSE

Therefore, this study was designed to explore potential mechanisms of DY in myocardial infarction (MI) by integrated strategy of metabolomics and network pharmacology.

METHODS

Cardiomyocytes were subjected to H2O2 induced myocardial injury and rats were induced MI via isoproterenol (ISO) injection. The entire metabolic alterations in serum and heart tissues of experimental rats were profiled by UPLC-MS/MS. Based on the identified differential metabolites, the pathway analysis results were obtained and further validated using the network pharmacology approach.

RESULTS

We found that DY exerted significant cardioprotective effects in vitro and in vivo, and ameliorated inflammatory cell infiltration and cardiomyocyte apoptosis induced by ISO. The metabolomics data suggested that DY mainly affected the amino acid metabolism (i.e., valine, leucine and isoleucine biosynthesis, arginine biosynthesis, phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arginine biosynthesis, glycine, serine, as well as the alanine metabolism, aspartate and glutamate metabolism, etc.). Simultaneously, DY participated in the regulation of the biosynthesis of bile acids and biosynthesis of unsaturated fatty acids. Notably, DY significantly reduced the biosynthesis of valine, leucine and isoleucine to regulating the metabolism of branched chain amino acids (BCAAs) in infarcted myocardium, thus blocking the inflammation via inhibiting the expression of NLRP3 inflammasome in ISO-induced rats. The anti-inflammatory system of DY was further validated with the results of network pharmacology.

CONCLUSION

Our study, for the first time, confirmed that DY inhibited inflammation and further exerted significant anti-myocardial infarction effect. Additionally, our work further demonstrated that the myocardial protective effect of DY was contributed to the inhibition of the NLRP3 inflammasome activation by regulating BCAAs in infarcted myocardium using the comprehensive metabolomics, molecular biology and network analysis. Overall, our study gained new insights into the role of the relationship between the metabolic regulation of BCAAs and the NLRP3 inflammasome against MI.

Vasorelaxant and Antioxidant Effects of Aframomum pruinosum Gagnep. (Zingiberaceae) Seed Extracts May Mediate Their Cardioprotective Activity against Isoproterenol-Induced Myocardial Infarction

Aframomum pruinosum seeds are traditionally used in Cameroon to treat cardiac palpitations. The present work evaluates the cardioprotective effects of the aqueous (AE) and ethanolic (EE) extracts from A. pruinosum seeds against isoproterenol-induced myocardial infarction. Male Wistar rats were pretreated for 14 days with AE or EE at doses of 75 and 150 mg/kg/day or propranolol (10 mg/kg/day). On days 15 and 16, they were injected subcutaneously with isoproterenol (85 mg/kg/day). Blood pressure and heart rate were weekly recorded by tail-cuff plethysmography during pretreatment and 24 hours after the second dose of isoproterenol. At the end of the treatment period, serum Lactate Dehydrogenase (LDH), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), cardiac nitric oxide (NO), myeloperoxidase (MPO), and oxidative stress parameters (SOD, catalase, MDA, and GSH) were assayed. Sections of left ventricle tissue were subjected to histological analysis. The vasorelaxant effects of cumulative concentrations of AE or EE (3–300 µg/mL) were evaluated on intact or endothelium-denuded isolated aorta rings precontracted with noradrenaline (1 µM). The vasorelaxant effects of the plant extracts were also tested in the presence of N^ω-nitro-L-arginine methyl ester (L-NAME; 100 µM). AE and EE significantly prevented blood pressure decrease and heart rate increase elicited by isoproterenol. Both plant extracts inhibited the increase in ALT, AST, NO, and MPO but did not prevent LDH surge. Oxidative stress parameters were improved following A. pruinosum pretreatment. AE and EE highly reduced cardiomyocyte necrosis and fibrosis but did not prevent leukocyte infiltration. Both extracts induced a concentration-dependent vasorelaxation that was significantly inhibited by the destruction of the endothelium and by L-NAME. Extracts of A. pruinosum exhibited cardioprotective effects, and EE was the most active. The cardioprotective effects of A. pruinosum extracts could be ascribed to their antioxidant, antinecrotic, and endothelium-dependent vasorelaxant effects.

Temporal Effect of Melatonin Posttreatment on Anoxia/Reoxygenation Injury in H9c2 Cells

Melatonin has been proven to reduce myocardial ischemia-reperfusion (MI/R) injury. However, in most studies, melatonin was administered prior to MI/R, thus, the results lack clinical significance in patients with acute myocardial infarction. We hypothesize that melatonin posttreatment at different times has different curative effects. Administered of Melatonin (150 μM) at different times after the onset of reoxygenation (t=-15, 0, 5, 10, 15, 30 min). Cellular apoptosis, oxidative stress and mitochondrial function were assessed. Mitophagy-related protein levels, the mitochondrial membrane potential (MMP) and mitochondrial permeability transition pore (mPTP) activity were also measured. A/R injury upregulated mitophagy, which was associated with increased cellular apoptosis, oxidative stress and mitochondrial dysfunction. Melatonin posttreatment (t= -15, 0, 5, 10, 15, 30 min) significantly inhibited excessive mitophagy after A/R injury, reduced cellular apoptosis and oxidative stress, restored mitochondrial function and MMP, and restrained mPTP opening. The therapeutic time window in which melatonin posttreatment protected H9c2 cells against A/R injury was large (from -15 to 30 min after the onset of reperfusion), but the earlier the melatonin administration was, the better its protective effect was. This mechanism is likely due to a reduction in mPTP activity and MMP collapse, which lead to the inhibition of mitophagy. This article is protected by copyright. All rights reserved.

Sex-specific impact of diabetes on all-cause mortality among adults with acute myocardial infarction: An updated systematic review and meta-analysis, 1988-2021

BACKGROUND

The prevalence of diabetes and its impact on mortality after acute myocardial infarction (AMI) are well-established. Sex-specific analyses of the impact of diabetes on all-cause mortality after AMI have not been updated and comprehensively investigated.

OBJECTIVE

To conduct a systematic review and meta-analysis that examined sex-specific short-term, mid-term and long-term all-cause mortality associated with diabetes among AMI survivors (diabetes versus non-diabetes patients in men and women separately), using up-to-date data.

METHODS

We systematically searched Embase and MEDLINE for studies that were published from inception to November 14, 2021. Studies were included if (1) they studied post-AMI all-cause-mortality in patients with and without diabetes, (2) sex-specific all-cause mortality at short-term (in-hospital or within 90 days after discharge), mid-term (>90 days and within 5 years), and/or long-term (>5 years) were reported. From eligible studies, we used random effects meta-analyses models to estimate pooled unadjusted and adjusted sex-specific risk ratio (RR) of all-cause mortality at short-, mid-, and long-term follow-up for adults with diabetes compared with those without diabetes.

RESULTS

Of the 3647 unique studies identified, 20 studies met inclusion criteria. In the unadjusted analysis (Total N=673,985; women=34.2%; diabetes patients=19.6%), patients with diabetes were at a higher risk for all-cause mortality at short-term (men: RR, 2.06; women: RR, 1.83); and mid-term follow-up (men: RR, 1.69; women: RR, 1.52) compared with those without diabetes in both men and women. However, when adjusted RRs were used (Total N=7,144,921; women=40.0%; diabetes patients=28.4%), the associations between diabetes and all-cause mortality in both men and women were attenuated, but still significantly elevated for short-term (men: RR, 1.16; 95% CI, 1.12-1.20; women: RR, 1.29; 95% CI, 1.15-1.46), mid-term (men: RR, 1.39; 95% CI, 1.31-1.46; women: RR, 1.38; 95% CI, 1.20-1.58), and long-term mortality (men: RR, 1.58; 95% CI, 1.22-2.05; women: RR, 1.76; 95% CI, 1.25-2.47). In men, all-cause mortality risk associated with diabetes tended to increase with the duration of follow-up (p<0.0001).

CONCLUSIONS

Diabetes has substantial and sustained effects on post-AMI all-cause mortality at short-term, mid-term and long-term follow-up, regardless of sex. Tailoring AMI treatment based on patients' diabetes status, duration of follow-up and sex may help narrow the gap in all-cause mortality between patients with diabetes and those without diabetes.

Impact of Delayed Pain to Needle and Variable Door to Needle Time On In-Hospital Complications in Patients With ST-Elevation Myocardial Infarction Who Underwent Thrombolysis: A Single-Center Experience

Background Myocardial infarction is a life-threatening event, and timely intervention is essential to improve patient outcomes and mortality. Previous studies have shown that the time to thrombolysis should be less than 30 minutes of the patient's arrival at the emergency room. Pain-to-needle time is a time from onset of chest pain to the initiation of thrombolysis, and door-to-needle time is a time between arrival to the emergency room to initiation of thrombolytic treatment. Ideally, the target for door-to-needle time should be less than 30 minutes; however, it is unclear if the door-to-needle time has a significant impact on patients presenting later than three hours from the onset of pain. As many of the previous studies were conducted in first-world countries, with established emergency medical services (EMS) systems and pre-hospital ST-elevation myocardial infarction (STEMI) triages and protocols, the data is not completely generalizable to developing countries. We, therefore, looked for the impact of the shorter and longer door-to-needle times on patient outcomes who presented to the emergency room (ER) with delayed pain-to-needle times (more than three hours of pain onset).  Objective To determine the impact of delayed pain-to-needle time (PNT) with variable door-to-needle time (DNT) on in-hospital complications (post-infarct angina, heart failure, left ventricular dysfunction, and death) in patients with ST-elevation myocardial infarction (STEMI) who underwent thrombolysis. Methods and results A total of 300 STEMI patients who underwent thrombolysis within 12 hours of symptoms onset were included, which were divided into two groups based on PNT. These groups were further divided into subgroups based on DNT. The primary outcome was in-hospital complications between the two groups and between subgroups within each group. The pain-to-needle time was ≤3 hours in 73 (24.3%) patients and >3 hours in 227 (75.7%) patients. In-hospital complications were higher in group II with PNT >3 hours (p <0.05). On subgroup analysis, in-hospital complications were higher with longer door-to-needle time in group II (p<0.05); however, there was no difference in complications among group I. Conclusion Our study is consistent with the fact that shorter door-to-needle time, even in patients with delayed PNT (>3 hours), has a significant impact on in-hospital complications with no difference in mortality.

Ultra-highly sensitive cardiac troponin I: Age and sex differences in healthy individuals

Background

Associations between elevated circulating cardiac troponin I (cTnI) levels and adverse cardiac outcomes were established prior to the ability to measure extremely low levels of cTnI. Immunoassays that achieve precise ultra-highly sensitive quantification of cTnI (u-hs-cTnI) will allow accurate measurement in healthy subjects. We aimed to evaluate the distribution of u-hs-cTnI values measured by (Simoa HD-1 Analyzer, Quanterix Corporation, Lexington, MA) in healthy subjects and characterize relations to sex and age.

Methods

Two independent, healthy cohorts (total of 200 women, 200 men) aged 18-86 years were analyzed in duplicate using the u-hs-cTnI Immunoassay. The u-hs-cTnI 99th percentiles were calculated as the upper limits considering a robust estimation against outliers with 90% confidence intervals. The Quanterix immunoassay analytical performance was established and compared to an existing clinical assay (ARCHITECT STAT High Sensitivity Troponin I, Abbott Laboratories, Wiesbaden, Germany).

Results

The lower limit of detection of the u-hs-cTnI assay was calculated to be 0.005 ng/L; we accurately quantified u-hs-cTnI in 95% of healthy individuals. The Quanterix immunoassay within overlapping concentrations correlated with the Abbott assay (R2 = 0.932). The calculated combined 99th percentile was 7.94 ng/L (90% Confidence Interval [CI], 5.47-10.52). Women had lower mean u-hs-cTnI concentrations than men under the age of 40 years. The sex-specific 99th percentile for female vs. male individuals was 4.89 ng/L (90%CI, 3.71-6.25) and 10.49 ng/L (90%CI, 5.19-15.06), respectively.

Conclusion

The Quanterix immunoassay provides precise quantification in 95% of healthy individuals. Women under the age of 40 years have significantly lower levels of u-hs-cTnI than men.

Mesenchymal stem cells seeded onto nanofiber scaffold for myocardial regeneration

Cardiac disease is the leading cause of mortality and disability worldwide. We investigated the role of undifferentiated adipose tissue-derived mesenchymal stem cells (ADMSC) alone and ADMSC seeded onto the electro-spun nanofibers (NF) for reconstructing damaged cardiac tissue in isoprenaline-induced myocardial infarction (MI) in rats. ADMSC were sorted by morphological appearance and by detection of cluster of differentiation (CD) surface antigens. The therapeutic potential of ADMSC for treating MI was evaluated by electrocardiogram (ECG), biochemical analysis, molecular genetic analysis and histological examination. Treatment of MI-challenged rats with ADMSC improved ECG findings, which were corroborated by significant decreases in serum lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) enzyme activities together with reduced serum troponin T (cTnT) and connexin 43 (Cx43) levels. MI model rats treated with ADMSC exhibited a significant increase in serum alpha sarcomeric actin (Actn) and GATA binding protein 4 (GATA4), and NK2 homeobox 5 (NKX2.5) gene expression was decreased following treatment with ADMSC. ADMSC also ameliorated damage to cardiac tissue. The effects of ADMSC seeded onto NF were superior to those of ADMSC alone. ADMSC may be useful for mitigation of MI.

Recent Advances in Cardiac Tissue Engineering for the Management of Myocardium Infarction

Myocardium Infarction (MI) is one of the foremost cardiovascular diseases (CVDs) causing death worldwide, and its case numbers are expected to continuously increase in the coming years. Pharmacological interventions have not been at the forefront in ameliorating MI-related morbidity and mortality. Stem cell-based tissue engineering approaches have been extensively explored for their regenerative potential in the infarcted myocardium. Recent studies on microfluidic devices employing stem cells under laboratory set-up have revealed meticulous events pertaining to the pathophysiology of MI occurring at the infarcted site. This discovery also underpins the appropriate conditions in the niche for differentiating stem cells into mature cardiomyocyte-like cells and leads to engineering of the scaffold via mimicking of native cardiac physiological conditions. However, the mode of stem cell-loaded engineered scaffolds delivered to the site of infarction is still a challenging mission, and yet to be translated to the clinical setting. In this review, we have elucidated the various strategies developed using a hydrogel-based system both as encapsulated stem cells and as biocompatible patches loaded with cells and applied at the site of infarction.

The Healthcare Cost Burden in Adults with High Risk for Cardiovascular Disease

OBJECTIVE

We calculated the short- and long-term care resource use and costs in adults with high-risk conditions for cardiovascular disease (HRCVD) as defined by the Canadian Cardiovascular Society dyslipidemia guidelines.

METHODS

We linked Alberta health databases to identify patients aged ≥ 18 years with HRCVD between fiscal year (FY) 2012 and FY2016. The first HRCVD event was the index event. Patients were categorized into (1) primary prevention patients and (2) secondary prevention patients at the index event and were followed until death, they moved out of the province, or they were censored at March 2018. We calculated the resource use and costs for each of the 5 years after the index event.

RESULTS

The study included 459,739 HRCVD patients (13,947 [3%] were secondary prevention patients). The secondary prevention patients were older (median age 61 years vs. 55 years; p < 0.001), and there were fewer females in this group (30.4% vs. 51.3%; p < 0.001). The total healthcare costs in the first year decreased over time (FY2012: 1.16 billion Canadian dollars (CA$); FY2016: CA$1.05 billion; p < 0.001). An HRCVD patient incurred CA$12,068, CA$5626, and CA$4655 during the first, second, and fifth year, respectively (p for trend < 0.001). During the first year, healthcare costs per secondary prevention patient (CA$36,641) were triple that for a primary prevention patient (CA$11,299; p < 0.001), primarily due to higher hospitalization costs in secondary prevention patients (CA$26,896 vs. CA$6051; p < 0.001).

CONCLUSIONS

The healthcare costs for HRCVD patients were substantial but decreased over time. The costs were highest in the year following the index event and decreased thereafter. Secondary prevention patients incurred higher costs than the primary prevention patients.

The cardioprotective effect and mechanism of bioactive glass on myocardial reperfusion injury

Myocardial reperfusion treatment for ischemic infarction may cause lethal injury of cardiomyocytes, which is known as ischemia/reperfusion (I/R) injury. As a kind of prospective biomaterial with superior properties, the application of bioactive glasses (BGs) in myocardial tissue engineering have received great interests. In this study, the cardioprotective effect and relevant mechanism of BG on myocardial reperfusion injury were investigatedin vitro. H9c2 cardiomyocytes were pretreated with BG extracts and then cultured in hypoxic environment for 30 min followed by reoxygenation for 1 h. The activity of released lactate dehydrogenase (LDH) and the content of malondialdehyde (MDA) in H9c2 cells were tested by assay kits. Cell viability was analyzed by Live/Dead staining assay and the number of living cells was detected by Cell Counting Kit-8 (CCK-8) assay. The cytoskeletal protein F-actin was stained and observed under inverted fluorescence microscope. Mitochondrial membrane potential (MMP) level, reactive oxygen species (ROS) production and apoptosis ratio were evaluated by fluorescent observation and flow cytometry simultaneously. The gene expressions relevant to apoptosis were detected by quantitative real time polymerase chain reaction (qRT-PCR) analysis. The results showed that BG extracts effectively inhibited hypoxia/reoxygenation (H/R)-induced cell injury by suppressing oxidative stress and mitochondrial permeability transition (MPT) within H9c2 cells. Meanwhile, apoptosis caused by H/R injury was alleviated and three classic apoptotic signaling pathways were proved to be regulated by BG extracts. Further analysis showed that phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway was up-regulated in H/R-induced H9c2 cells by BG extracts, leading to relieved cellular apoptosis. These results indicated that BG might exert cardioprotective effect in reperfusion injury when applied in myocardial tissue regeneration and repair.

Machine learning enhances the performance of short and long-term mortality prediction model in non-ST-segment elevation myocardial infarction

Machine learning (ML) has been suggested to improve the performance of prediction models. Nevertheless, research on predicting the risk in patients with acute myocardial infarction (AMI) has been limited and showed inconsistency in the performance of ML models versus traditional models (TMs). This study developed ML-based models (logistic regression with regularization, random forest, support vector machine, and extreme gradient boosting) and compared their performance in predicting the short- and long-term mortality of patients with AMI with those of TMs with comparable predictors. The endpoints were the in-hospital mortality of 14,183 participants and the three- and 12-month mortality in patients who survived at discharge. The performance of the ML models in predicting the mortality of patients with an ST-segment elevation myocardial infarction (STEMI) was comparable to the TMs. In contrast, the areas under the curves (AUC) of the ML models for non-STEMI (NSTEMI) in predicting the in-hospital, 3-month, and 12-month mortality were 0.889, 0.849, and 0.860, respectively, which were superior to the TMs, which had corresponding AUCs of 0.873, 0.795, and 0.808. Overall, the performance of the predictive model could be improved, particularly for long-term mortality in NSTEMI, from the ML algorithm rather than using more clinical predictors.

The evolving cardiac lymphatic vasculature in development, repair and regeneration

The lymphatic vasculature has an essential role in maintaining normal fluid balance in tissues and modulating the inflammatory response to injury or pathogens. Disruption of normal development or function of lymphatic vessels can have severe consequences. In the heart, reduced lymphatic function can lead to myocardial oedema and persistent inflammation. Macrophages, which are phagocytic cells of the innate immune system, contribute to cardiac development and to fibrotic repair and regeneration of cardiac tissue after myocardial infarction. In this Review, we discuss the cardiac lymphatic vasculature with a focus on developments over the past 5 years arising from the study of mammalian and zebrafish model organisms. In addition, we examine the interplay between the cardiac lymphatics and macrophages during fibrotic repair and regeneration after myocardial infarction. Finally, we discuss the therapeutic potential of targeting the cardiac lymphatic network to regulate immune cell content and alleviate inflammation in patients with ischaemic heart disease.

Role of Transient Receptor Potential Vanilloid 4 in Vascular Function

Transient receptor potential vanilloid 4 (TRPV4) channels are widely expressed in systemic tissues and can be activated by many stimuli. TRPV4, a Ca²⁺-permeable cation channel, plays an important role in the vasculature and is implicated in the regulation of cardiovascular homeostasis processes such as blood pressure, vascular remodeling, and pulmonary hypertension and edema. Within the vasculature, TRPV4 channels are expressed in smooth muscle cells, endothelial cells, and perivascular nerves. The activation of endothelial TRPV4 contributes to vasodilation involving nitric oxide, prostacyclin, and endothelial-derived hyperpolarizing factor pathways. TRPV4 activation also can directly cause vascular smooth muscle cell hyperpolarization and vasodilation. In addition, TRPV4 activation can evoke constriction in some specific vascular beds or under some pathological conditions. TRPV4 participates in the control of vascular permeability and vascular damage, particularly in the lung capillary endothelial barrier and lung injury. It also participates in vascular remodeling regulation mainly by controlling vasculogenesis and arteriogenesis. This review examines the role of TRPV4 in vascular function, particularly in vascular dilation and constriction, vascular permeability, vascular remodeling, and vascular damage, along with possible mechanisms, and discusses the possibility of targeting TRPV4 for therapy.

Kuanxiong aerosol inhibits apoptosis and attenuates isoproterenol-induced myocardial injury through the mitogen-activated protein kinase pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Kuanxiong aerosol (KXA) is a common clinical drug based on Fangxiang Wentong (FXWT) therapy in the treatment of angina pectoris. However, the pharmacological mechanism of KXA in the prevention and treatment of myocardial injury (MI) is not clear.

AIM OF THE STUDY

The purpose of this study was to explore the protective effect of KXA on isoproterenol (ISO)-induced MI in rats.

MATERIALS AND METHODS

The study included male Wistar Kyoto rats (age: 6 weeks). The rats were randomly divided into the following 5 groups (n = 6 per group): control group, ISO group, isosorbide mononitrate (ISMN) group (5 mg/kg), KXA-L group (0.1 mL/kg), and KXA-H group (0.3 mL/kg). The rats in the last three groups were given intragastric administration for 14 days, and rats in control group and ISO group were given the same amount of normal saline daily. ISO (120 mg/kg) was used to induce MI on the 13th and 14th days. We assessed electrocardiograms (ECGs), myocardial specific enzymes, histopathological changes, and apoptosis.

RESULTS

We found that KXA reduced the increase in the ST-segment amplitude (elevation or depression) and the levels of myocardial marker enzymes induced by ISO in MI rats, improved the pathological changes in myocardial tissue, and reduced cardiomyocyte apoptosis. At the same time, KXA significantly inhibited the up-regulation of caspase-3 and Bax expression and down-regulation of Bcl-2 expression induced by ISO. RNA sequencing showed that 90 up-regulated genes induced by ISO were down-regulated after KXA treatment, whereas 27 down-regulated genes induced by ISO were up-regulated after KXA treatment. In addition, KEGG pathway enrichment analysis showed that the mitogen-activated protein kinase (MAPK) signaling pathway may be an important target of KXA in the treatment of ISO-induced MI in rats. The results of RNA sequencing verified by Western blot analysis showed that KXA significantly inhibited the activation of the ISO-induced MAPK pathway.

CONCLUSIONS

KXA improves cardiac function in MI rats by inhibiting apoptosis mediated by the MAPK signaling pathway.