Circulating miRNA-21 as a diagnostic biomarker for acute coronary syndrome: a systematic review and meta-analysis of diagnostic test accuracy study.

Background: Both early detection and treatment for acute coronary syndrome (ACS) have positively affected prognosis. A microRNA, miRNA-21 (miR-21), may have additional diagnostic potential for ACS among the others. This systematic review and meta-analysis aimed to evaluate the potential role of miR-21 in identifying ACS. Methods: PubMed, EMBASE and CENTRAL databases were searched up to March 17, 2024, for case-control and cohort studies assessing the diagnostic value of circulating miR-21 in patients with ACS. The search was limited to studies published in either English or Chinese. The primary outcome was the discriminative ability to circulate miR-21 for ACS, represented by the area under the standard receiver operating characteristic curve (AUC) analysis. Meta-analyses combined the AUCs using a random-effects model. Heterogeneity among the studies was detected by the I2 and Q statistics. The quality of the studies included was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2. Publication bias analysis was assessed constructing by the Egger's test (PROSPERO: CRD42020209424). Results: Eleven case-control studies containing a total of 2,413 subjects with 1,236 ACS cases and 1,177 controls were included. The mean age of participants in these studies ranges between 51.0 and 69.0 years. The meta-analysis showed an overall pooled AUC of 0.779 [95% confidence interval (CI): 0.715-0.843], with high heterogeneity noted between the studies (Q statistic =190.64, I2=94.23%, P<0.001). In subgroup analyses according to the subtypes of ACS, a pooled AUC of 0.767 (95% CI: 0.648-0.887) was derived from the studies focused on acute myocardial infarction cases only. The pooled AUC for unstable angina was 0.770 (95% CI: 0.718-0.822). In subgroup analyses according to the types of control groups, pooled AUC for ACS versus healthy controls was 0.779 (95% CI: 0.715-0.843), whereas the pooled AUC for ACS versus unhealthy controls was 0.740 (95% CI: 0.645-0.836). The quality assessment showed that the studies' overall quality was moderate. No evidence of publication bias was noted (P=0.49). Conclusions: Circulating miR-21 shows abilities to differentiate between ACS and non-ACS, suggesting its potential as a novel diagnostic biomarker for ACS. However, the evidence is weakened by high heterogeneity observed among the studies. Further research is essential before it can be applied in clinical practice.

Coronary microvascular dysfunction and myocardial area at risk assessed by cadmium zinc telluride single photon emission computed tomography after primary percutaneous coronary intervention in acute myocardial infarction patients.

Background: A high proportion of coronary microvascular dysfunction (CMD) has been observed in patients with acute myocardial infarction (AMI) who have received primary percutaneous coronary intervention (PCI), which may affect their prognosis. This study used cadmium zinc telluride (CZT) single photon emission computed tomography (SPECT) to evaluate the prevalence and characteristics of CMD and myocardial area at risk (AAR) in AMI patients who had undergone primary PCI. Methods: We conducted a single-center cross-sectional retrospective study at TEDA International Cardiovascular Hospital from September 2021 to June 2022. A total of 83 patients received primary PCI for AMI. Subsequently, a rest/stress dynamic and routine gated myocardial perfusion imaging (MPI) were performed 1 week after PCI. The CMD group was defined as having a residual stenosis of infarct-related artery (IRA) <50% and myocardial flow reserve (MFR) <2.0 in this corresponding territory, whereas MFR ≥2.0 of IRA pertained to the normal control group. Rest-AAR of infarction (%) and stress-AAR (%) were expressed by the percentage of measured rest-defect-size and stress-defect-size in the left ventricular area, respectively. Logistic regression analyses were performed to identify significant predictors of CMD. Results: A total of 53 patients with a mean age of 57.06±11.99 years were recruited, of whom 81.1% were ST-segment elevation myocardial infarction (STEMI). The proportion of patients with CMD was 79.2% (42/53). The time of pain to SPECT imaging was 7.50±1.27 days in the CMD group and 7.45±1.86 days among controls. CMD patients had a higher body mass index (BMI) than controls (26.48±3.26 vs. 24.36±2.73 kg/m2, P=0.053), and a higher proportion of STEMI, thrombolysis in myocardial infarction (TIMI) 0 grade of IRA prior PCI than controls (88.1% vs. 54.5%, P=0.011; 61.9% vs. 18.2%, P=0.004, respectively). No significant difference was identified in the rest-myocardial blood flow (MBF) of IRA between the 2 groups, whereas the stress-MBF and MFR of IRA, rest-AAR, and stress-AAR in the CMD group were remarkably lowered. Higher BMI [odds ratio (OR): 1.332, 95% confidence interval (CI): 1.008-1.760, P=0.044] and stress-AAR (OR: 1.994, 95% CI: 1.122-3.543, P=0.019) were used as independent predictors of CMD occurrence. Conclusions: The prevalence of CMD is high in AMI patients who received primary PCI. Each 1 kg/m2 increase in BMI was associated with a 1.3-fold increase in CMD risk. A 5% increase in stress-AAR was associated with a nearly 2-fold increase in CMD risk. Increased BMI and stress-AAR predicts decreased coronary reserve function.

A review regarding the article 'Traditional Chinese medicine compound (Tongxinluo) and clinical outcomes of patients with acute myocardial infarction the CTS-AMI randomized clinical trial'.

Tongxinluo, a traditional Chinese medicine compound, has shown promise in improving outcomes for patients with ST-segment elevation myocardial infarction (STEMI). This randomized, double-blind, placebo-controlled trial investigated the efficacy of Tongxinluo in reducing major adverse cardiac and cerebrovascular events (MACCEs) in STEMI patients. The study enrolled 3777 patients from 124 hospitals in China, all of whom received standard STEMI treatments in addition to either Tongxinluo or placebo for 12 months. The primary endpoint was the occurrence of MACCEs at 30 days, with secondary endpoints including individual components of MACCEs, severe STEMI complications, major bleeding, and all-cause mortality at 1 yr. Results showed that Tongxinluo significantly reduced the 30-day MACCE rate compared to placebo (3.4 % vs 5.2 %), and this benefit persisted at 1 year (5.3 % vs 8.3 %). Cardiac death and myocardial reinfarction rates were also significantly lower in the Tongxinluo group. These findings underscore the importance of integrating traditional Chinese medicine with conventional Western medical treatments, providing significant evidence to support the development of evidence-based practices in traditional Chinese medicine. This study represents a pivotal advancement in the field of TCM, demonstrating its potential to contribute meaningfully to modern clinical practice and highlighting the necessity for further high-quality research in this area.

MicroRNA-322-5p targeting Smurf2 regulates the TGF-ß/Smad pathway to protect cardiac function and inhibit myocardial infarction.

Acute coronary artery blockage leads to acute myocardial infarction (AMI). Cardiomyocytes are terminally differentiated cells that rarely divide. Treatments preventing cardiomyocyte loss during AMI have a high therapeutic benefit. Accumulating evidence shows that microRNAs (miRNAs) may play an essential role in cardiovascular diseases. This study aims to explore the biological function and underlying regulatory molecular mechanism of miR-322-5p on myocardial infarction (MI). This study's miR-322-5p is downregulated in MI-injured hearts according to integrative bioinformatics and experimental analyses. In the MI rat model, miR-322-5p overexpression partially eliminated MI-induced changes in myocardial enzymes and oxidative stress markers, improved MI-caused impairment on cardiac functions, inhibited myocardial apoptosis, attenuated MI-caused alterations in TGF-ß, p-Smad2, p-Smad4, and Smad7 protein levels. In oxygen-glucose deprivation (OGD)-injured H9c2 cells, miR-322-5p overexpression partially rescued OGD-inhibited cell viability and attenuated OGD-caused alterations in the TGF-ß/Smad signaling. miR-322-5p directly targeted Smurf2 and inhibited Smurf2 expression. In OGD-injured H9c2 cells, Smurf2 knockdown exerted similar effects to miR-322-5p overexpression upon cell viability and TGF-ß/Smad signaling; moreover, Smurf2 knockdown partially attenuated miR-322-5p inhibition effects on OGD-injured H9c2 cells. In conclusion, miR-322-5p is downregulated in MI rat heart and OGD-stimulated rat cardiomyocytes; the miR-322-5p/Smurf2 axis improves OGD-inhibited cardiomyocyte cell viability and MI-induced cardiac injuries and dysfunction through the TGF-ß/Smad signaling.

Dipeptidyl peptidase-4 inhibitors versus sulfonylureas on the top of metformin in patients with diabetes and acute myocardial infarction.

Background: Recent trials have shown that both the extent of glycated hemoglobin reduction and the duration of enhanced glycemic control are major factors that may affect cardiovascular outcome results. We aimed to investigate the impact of metformin (MET) combined with dipeptidyl peptidase-4 (DPP4) inhibitors or sulfonylureas (SU) on long-term clinical outcomes in patients with acute myocardial infarction (AMI) and type 2 diabetes mellitus (DM). Methods: This study was a prospective cohort trial. From November 2011 to December 2015, a total of 13,104 AMI patients were consecutively enrolled from the Korea AMI registry-National Institutes of Health. The patients were divided into the MET + DPP4 inhibitors group and the MET + SU group. The primary endpoint, major adverse cardiac events (MACE), was defined as the composite of all-cause death, recurrent myocardial infarction (MI), and any repeat revascularization up to 3-year follow-up. To adjust baseline potential confounders, an inverse probability weighting (IPTW) analysis was performed. Results: Baseline well-matched two groups were generated (the MET + DPP4 inhibitors group, n=468 and the MET + SU group, n=468). During 3-year clinical follow-up, the cumulative incidence of MACE between the two groups was not significantly different after adjustment (16.8% for MET + DPP4 inhibitors group vs. 19.4% for MET + SU group, P=0.302). However, the MET + DPP4 inhibitors group was associated with reduced risk of MI [1.3% vs. 4.9%; hazard ratio (HR): 0.228, 95% confidence interval (CI): 0.090-0.580, P=0.001] than the MET + SU group. Conclusions: In patients with AMI and type 2 DM, the use of MET combined with DPP4 inhibitors was associated with reduced incidence of recurrent MI than MET combined with SU during 3-year follow-up.

Predictive effect of triglyceride-glucose index on No-Reflow Phenomenon in patients with type 2 diabetes mellitus and acute myocardial infarction undergoing primary percutaneous coronary intervention.

OBJECTIVE: Triglyceride glucose (TyG) index is considered as a new alternative marker of insulin resistance and a clinical predictor of type 2 diabetes mellitus (T2DM) combined with coronary artery disease. However, the prognostic value of TyG index on No-Reflow (NR) Phenomenon in T2DM patients with acute myocardial infarction (AMI) remains unclear. METHODS: In this retrospective study, 1683 patients with T2DM and AMI underwent primary percutaneous coronary intervention (PCI) were consecutively included between January 2014 and December 2019. The study population was divided into two groups as follows: Reflow (n = 1277) and No-reflow (n = 406) group. The TyG index was calculated as the ln [fasting triglycerides (mg/dL)×fasting plasma glucose (mg/dL)/2].Multivariable logistic regression models and receiver-operating characteristic curve analysis were conducted to predict the possible risk of no-reflow. Net Reclassification Improvement (NRI) and Integrated Discrimination Improvement (IDI) were calculated to determine the ability of the TyG index to contribute to the baseline risk model. RESULTS: Multivariable logistic regression models revealed that the TyG index was positively associated with NR[OR,95%CI:5.03,(2.72,9.28),p<0.001] in patients with T2DM and AMI. The area under the curve (AUC) of the TyG index predicting the occurrence of NR was 0.645 (95% CI 0.615-0.673; p < 0.001)], with the cut-off value of 8.98. The addition of TyG index to a baseline risk model had an incremental effect on the predictive value for NR [net reclassification improvement (NRI): 0.077(0.043to 0.111), integrated discrimination improvement (IDI): 0.070 (0.031to 0.108), all p < 0.001]. CONCLUSIONS: High TyG index was associated with an increased risk of no-reflow after PCI in AMI patients with T2DM. The TyG index may be a valid predictor of NR phenomenon of patients with T2DM and AMI. Early recognition of NR is critical to improve outcomes with AMI and T2DM patients.

Association between triglyceride-glucose index and acute kidney injury in patients with acute myocardial infarction based on medical information mart for intensive care database: A cross-sectional study.

Background: The relationship between triglyceride glucose (TyG) index and the incidence of acute kidney injury (AKI) in patients with acute myocardial infarction (AMI) is unclear. This study aims to explore the relationship between the two. Methods: Participants were enrolled from Medical Information Mart for Intensive Care IV (MIMICIV) and grouping of subjects based on the quartile interval of the TyG index. With the presence of AKI as the main outcome, a logistic regression model was constructed. The correlation of the TyG index with the results obtained was examined by using a restricted cubic spline (RCS) model.

Long-term prognostic importance of high levels of sST2 in patient with AMI: a meta-analysis.

OBJECTIVE: This meta-study aimed to assess the connection between soluble suppression of tumorigenicity 2 (sST2) and extended clinical outcomes in individuals diagnosed with acute myocardial infarction (AMI). METHODS: We systematically collected pertinent literature from PubMed, Embase and Web of Science. The primary effect measures employed in this research were the hazard ratio and 95% confidence intervals. The quality and publication bias of included studies were evaluated. Subgroup analysis was conducted to explore the diversity in study outcomes. RESULTS: This comprehensive meta-analysis ultimately encompassed thirteen studies, involving a total of 11,571 patients. Elevated levels of sST2 were identified as an adverse prognostic indicator, demonstrating a substantial association not only with overall mortality (combined HR 2.4, 95% CI 1.6-3.5, P < 0.01) but also with major adverse cardiovascular events (MACEs) (HR 2.5, 95% CI 1.5-4.2, P < 0.01). Subgroup analyses revealed that increased sST2 levels were linked to higher rates of all-cause mortality and MACEs in patients with ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and other unselected subcategories of AMI. CONCLUSION: Increased sST2 could predict the long-term prognosis in patients suffering from AMI.

Association between lactate/albumin ratio and prognosis in patients with acute myocardial infarction.

BACKGROUND: The association between the lactate/albumin ratio (L/A) as a diagnostic indicator and unfavourable clinical outcomes has been established in patients with community-acquired pneumonia, sepsis and heart failure, but the connection between L/A and all-cause mortality in patients with acute myocardial infarction (AMI) has yet to be fully understood. METHODS: This was a retrospective cohort study using MIMIC-IV (v2.2) data, with 2816 patients enrolled and all-cause mortality during hospitalization as the primary outcome. Kaplan-Meier (KM) analysis was used to compare the all-cause mortality between high-level and low-level L/A groups. Receiver operating characteristic (ROC) curve, Restricted cubic splines (RCS) and Cox proportional hazards analysis were performed to investigate the relationship between L/A ratio and in-hospital all-cause mortality. RESULTS: L/A values were significantly higher in the non-survivor groups than the survival groups (1.14 [.20] vs. .60 [.36], p < .05), and area under the ROC curve [.734 (95% confidence interval, .694-.775)] was better than other indicators. Data of COX regression analysis showed that higher L/A value supposed to be an independent risk factor for in-hospital mortality. RCS analysis showed evidence of an increasing trend and a non-linear relationship between L/A and in-hospital mortality (p-value was non-linear <.05). KM survival curves were significantly lower in the high L/A group than the low L/A group (p < .001), and the former group had an increased risk of in-hospital mortality compared with the latter one (Log Rank p < .001). CONCLUSIONS: L/A demonstrates significant independent predictive power for elevated all-cause mortality during hospitalization in patients diagnosed with AMI.

Circ_0004771 Promotes Hypoxia/Reoxygenation Induced Cardiomyocyte Injury via Activation of Mitogen-Activated Protein Kinase Signaling Pathway.

This study aimed to observe the mechanism and effect of circ_0004771 on cardiomyocyte injury in acute myocardial infarction (AMI). The differences in circ_0004771 expression in the blood of AMI patients and healthy volunteers were observed by Real-Time Quantitative Reverse Transcription-Polymerase Chain Reaction. AMI cell models were constructed by hypoxia/reoxygenation (H/R)-induced injury in human cardiomyocytes (AC16 cells). The changes of circ_0004771 expression in AMI cells were observed. After transfection with the knockdown or overexpression of circ_0004771 vector in AMI cells, Cell Counting Kit-8 (CCK-8) assay and propidium iodide/FITC-Annexin V staining were performed to detect cell proliferation and apoptosis levels, extracellular lactate dehydrogenase (LDH) activity, malondialdehyde (MDA) concentration, and superoxide dismutase (SOD) activity. Expression levels of Mitogen-activated protein kinase (MAPK) signaling pathway-related proteins (p-MEK1/2, MEK1/2, p-ERK1/2, ERK1/2), and endoplasmic reticulum (ER) stress proteins (GRP78 and CHOP-1) were observed in each group of cells by western blot method. The expression level of circ_0004771 was significantly reduced in both clinical samples and cells of AMI. When circ_0004771 was knocked down in AMI cells, it resulted in a decrease in cell proliferation level and significant increase in apoptosis level. The inhibition of circ_0004771 expression caused leakage of LDH in AMI cells, accumulation of intracellular MDA, and inhibition of SOD activity. In addition, the knockdown of circ_0004771 significantly increased the levels of p-MEK1/2, p-ERK1/2, GRP78, and CHOP-1 in H/R-induced AC16 cells. However, the overexpression of circ_0004771 resulted in the opposite result as when circ_0004771 was knocked down. A low level of circ_0004771 in AMI activates the MAPK signaling pathway in cardiomyocytes as well as encourages intracellular oxidative stress and ER stress, thereby inhibiting cell proliferation and promoting apoptosis.

Elevated circulating inflammatory biomarker levels in the SIRT1-NF-κB-sCD40L pathway in patients with acute myocardial infarction: a case-control study.

BACKGROUND: Inflammation plays a key role in atherosclerosis development and progression. However, the role of novel inflammatory biomarker pathways, namely the SIRT1-NF-κB-sCD40L, in the etiopathogenesis of human atherosclerosis remains undefined. This study was designed to evaluate the changes and clinical implications of these inflammatory mediators in the plasma of patients with acute myocardial infarction (AMI). METHODS: The peripheral arterial blood of 88 participants (68 patients with AMI and 20 age-matched controls), was drawn prior to performing coronary angiography (CAG). The SIRT1, NF-κB, and sCD40L plasma levels were quantified using ELISA. Spearman's analysis was used to evaluate the correlation between the three inflammatory markers, while Pearson's test assessed their potential correlation with cardiac troponin T (TNT) levels. Sensitivity, specificity, and area under the ROC curve (AUC) were calculated as measures of diagnostic accuracy. RESULTS: Patients with AMI showed higher levels of circulating SIRT1, NF-κB, and sCD40L compared to the age-matched controls (p < 0.05). However, the plasma concentrations of these three inflammatory mediators did not differ between the ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) patients. Additionally, in patients with AMI, the SIRT1 level was positively correlated with NF-κB and sCD40L levels (p < 0.001). Likewise, the levels of SIRT1, NF-κB and sCD40L were positively correlated with TNT levels (p < 0.001). More importantly, the ROC analysis showed that the diagnostic accuracy of AMI was significantly higher when NF-κB or sCD40L level was used in combination with TNT levels (p < 0.05). CONCLUSIONS: The levels of the circulating inflammatory biomarkers, including SIRT1, NF-κB, and sCD40L, were significantly elevated in patients with AMI. These novel biomarkers can improve the diagnostic accuracy of AMI when combined with TNT.KEY MESSAGESAMI is a potentially lethal CAD and is the leading cause of mortality and morbidity worldwide. Inflammation plays a key role in atherosclerosis development and progression. The levels of the circulating novel inflammatory biomarkers, including SIRT1, NF-κB, and sCD40L, were significantly elevated in patients with AMI.The SIRT1 level was positively correlated with NF-κB and sCD40L levels in patients with AMI.The levels of SIRT1, NF-κB and sCD40L were positively correlated with TNT levels.The ROC analysis showed that the diagnostic accuracy of AMI was significantly higher when NF-κB or sCD40L level was used in combination with TNT levels.SIRT1/NF-κB/sCD40L axis inhibition is a potential new target for AMI treatment.

Diagnostic and treatment value of XPNPEP3 in acute myocardial infarction.

Background: At present, acute myocardial infarction (AMI) is a serious cardiovascular disease with high morbidity and mortality. Discovering biomarkers of AMI is important for clinical diagnosis and needs. Therefore, this study aimed to elucidate the role of XPNPEP3 as a potential biomarker for AMI. Methods: Expression profiling data were downloaded for AMI patients and healthy patients in the GSE24548 and GSE24519 datasets, respectively. The limma package in R was conducted to determine differentially expressed microRNA (DEmiRNA)/messenger RNA (mRNA) [differentially expressed genes (DEGs)]. TargetScan and Cytoscape were used to build regulatory network of miRNA-mRNA. The Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) and Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) were applied to determine immune cell score. The gene set variation analysis (GSVA) package was used to calculate pathway score. Key drugs were determined by protein-protein interaction (PPI) and molecular docking. Results: Totals of 36 DEmiRNAs and 63 DEGs were determined in the GSE24584 dataset and GSE24519 dataset, respectively, and then we constructed a miRNA-mRNA network including 31 DEmiRNAs and 47 DEGs. The correlation analysis between immune cells and 47 DEGs identified that XPNPEP3 was most associated with AMI. Furthermore, XPNPEP3 was negatively correlated with inflammatory response score. A diagnosis model based on XPNPEP3 expression showed an area under the curve (AUC) of 93.38%, and 159 genes were highly correlated with XPNPEP3. Molecular docking analysis showed that DB06909 had the lowest docking score with XPNPEP3, revealing it to be a potential XPNPEP3 inhibitor. Conclusions: This work discovered that XPNPEP3 is correlated with the development of AMI. These findings may provide theoretical basis for the diagnosis and treatment of AMI.

Successful conservative treatment for left ventricular free wall rupture after acute myocardial infarction.

Left ventricular free wall rupture (LVFWR) is a rare but fatal complication of acute myocardial infarction (AMI). An 81-year-old female patient with several cardiovascular risk factors presented to the emergency department with symptoms of developing a chronic stomachache and cold sweat. An echocardiograph showed wall motion abnormalities from the lateral to posterior wall, as well as pericardial effusion containing clots of up to 17 mm in the posterior wall that indicated LVFWR after AMI. Although she was conscious after being brought to the initial care unit, she suddenly lost consciousness and fell into electromechanical dissociation (EMD). Endotracheal intubation was immediately initiated and her pericardial drainage and intra aortic balloon pump (IABP) placement, and hemodynamics recovered. Although she had 100% obstruction in the left circumflex artery (LCX) #12 on coronary angiography (CAG), she was discharged to the Intensive Care Unit (ICU) without percutaneous coronary intervention (PCI). Conservative treatment such as intubation, sedation, pericardiocentesis and strict blood pressure management as well as treatment by IABP long-term support led to the patient being uneventfully discharged after 60 days.

Development of a prediction model for exercise tolerance decline in the exercise assessment of patients with acute myocardial infarction undergoing percutaneous coronary intervention revascularization in the acute phase.

Background: Early cardiopulmonary exercise test (CPET) may predict the prognosis of patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI). However, data from CPET to assess the exercise capacity of patients with AMI PCI are still scarce. This study aimed to evaluate the safety of the CPET and assess the predictors and clinical influence of exercise capacity measured by CPET in patients with AMI within 1 week after PCI. Methods: A total of 275 patients with AMI who underwent PCI in the acute phase were selected. Reduced exercise capacity was defined as peak oxygen uptake (VO2peak) <16 mL/kg/min. According to VO2peak, patients were divided into a normal exercise tolerance group and a reduced exercise tolerance group. The general clinical conditions were compared between the 2 groups to investigate the safety of CPET and the influencing factors of exercise tolerance. A nomogram model for predicting patients' exercise capacity was further developed. Clinical outcomes were recorded. Results: The median time of CPET in all patients was 5 days after PCI. Among the 275 patients, exercise tolerance decreased in 90 cases (32.72%). Multivariate logic analysis showed that E/e', age, glycosylated hemoglobin, and estimated glomerular filtration rate (eGFR) were independent predictors of early exercise capacity reduction in these patients. Utilizing the correlation coefficients from pre-assessment clinical and CPET indicators within the logistic regression framework, we constructed a nomogram model to forecast the diminishing exercise tolerance in AMI patients. The predictive accuracy of this model, as indicated by a C-index of 0.771 and an area under the receiver operating characteristic (ROC) curve of 0.771 (95% CI: 0.710-0.832), demonstrates its potential as a robust tool in clinical settings. During a follow-up of 24 months, the incidence of clinical outcomes in patients with low exercise tolerance was significantly higher than that in patients with normal exercise tolerance, among which all-cause mortality and reinfarction were statistically different (P=0.009 and P=0.043). Conclusions: The reduced exercise capacity in patients with AMI after initial PCI is related to age, diastolic dysfunction, renal function, and blood glucose control, which may lead to poor clinical prognosis. The nomogram prediction model performed well in predicting the declining exercise tolerance of patients with AMI.

COVID-19 STEMI related to microthrombi may lead to coronary microvascular dysfunction.

Coronavirus disease 2019 (COVID-19) increases the risk of ST-segment elevation myocardial infarction (STEMI), and is associated with a higher occurrence of nonobstructive coronary artery disease. We present a unique case of STEMI with concomitant COVID-19 infection in a young female found to have slow flow in multiple vessels on angiography, likely due to microvascular thrombi. Three months later, the patient developed coronary microvascular dysfunction (CMD), suggesting an evolution of microvascular thrombi and injury into subsequent CMD.

Protectin D1 Alleviates Myocardial Ischemia/Reperfusion Injury by Regulating PI3K/AKT Signaling Pathway.

Myocardial ischemia/reperfusion (I/R) injury after the onset of acute myocardial infarction (AMI) can be life-threatening, and there is no effective strategy for therapeutic intervention. Here, we studied the potential of protectin D1 in protecting from I/R-induced cardiac damages and investigated the underlying mechanisms. An in vivo rat model of I/R after AMI induction was established through the ligation of the left anterior descending (LAD) artery to assess the cardiac functions and evaluate the protective effect of protectin D1. Protectin D1 protected against I/R-induced oxidative stress and inflammation in the rat model, improved the cardiac function, and reduced the infarct size in myocardial tissues. The beneficial effect of protectin D1 was associated with the up-regulation of miRNA-210 and the effects on PI3K/AKT signaling and HIF-1α expression. Together, our data suggest that protectin D1 could serve as a potential cardioprotective agent against I/R-associated cardiac defects.

Compositional alterations of the gut microbiota in acute myocardial infarction patients with type 2 diabetes mellitus.

Background: Type 2 diabetes mellitus (T2DM) is a risk factor for acute myocardial infarction (AMI) and a common comorbidity in patients with AMI. T2DM doubles the fatality rate of patients with AMI in the acute phase of AMI and the follow-up period. However, the mechanisms by which T2DM increases the fatality rate remain unknown. This study sought to investigate changes in the gut microbiota of patients with AMI and T2DM (AMIDM) to extend understandings of the relative mechanisms from the aspects of gut microbiota. Methods: Patients were recruited and divided into 2 groups comprising 15 patients with AMIDM and 15 patients with AMI but without T2DM (AMINDM). Their stool samples and clinical information were collected. 16S ribosomal DNA sequencing was used to analyze the structure and composition of the gut microbiota based on the operational taxonomic units. Results: A significant difference was observed in the gut microbiota ß diversity between the 2 groups. At the phylum level, the AMIDM patients showed an increase in the abundance of Firmicutes and a decrease in the abundance of Bacteroidetes compared to the AMINDM patients. At the genus level, the AMIDM patients showed an increase in the abundance of Companilactobacillus, Defluvitaleaceae UCG-011 and UCG-009, and a decrease in the abundance of Phascolarctobacterium and CAG 56 compared to the AMINDM patients. At the species level, the AMIDM patients showed an increase in the abundance of species unclassified NK4A214 group, Bacteroides clarus, Coprococcus comes, unclassified Defluviltaleaceae UCG-011, uncultured rumen bacterium, unclassified CAG 56, Barnesiella intestinihominis, Lachnospiraceae bacterium, Bacteroides nordii, unclassified UCG-009, and the Family XIII AD3011 group compared to the AMINDM patients. The gut microbiota function predictions indicated that the nucleotide metabolism-related pathway was significantly more increase in the patients with AMIDM than those with AMINDM. Additionally, the patients with AMIDM showed an increase in gram-positive bacteria and a decrease in the proportion of gram-negative bacteria. Our correlation analysis results on the gut microbiota and clinical parameters might extend understandings of the progression of AMI. Conclusions: Changes in the gut microbiota composition of patients with AMIDM affect the severity of the metabolic disturbance and may be responsible for poorer clinical outcomes and worse disease progression in patients with AMIDM compared to those with AMINDM.

Acute myocardial infarction after inactivated COVID-19 vaccination: a case report and literature review.

A number of vaccines have been developed and deployed globally to restrain the spreading of the coronavirus disease 2019 (COVID-19). The adverse effect following vaccination is an important consideration. Acute myocardial infarction (AMI) is a kind of rare adverse event after COVID-19 vaccination. Herein, we present a case of an 83-year-old male who suffered cold sweat ten minutes after the first inactivated COVID-19 vaccination and AMI one day later. The emergency coronary angiography showed coronary thrombosis and underlying stenosis in his coronary artery. Type II Kounis syndrome might be a potential mechanism, which is manifested as coronary thrombosis secondary to allergic reactions in patients with underlying asymptomatic coronary heart disease. We also summarize the reported AMI cases post COVID-19 vaccination, as well as overview and discuss the proposed mechanisms of AMI after COVID-19 vaccination, thus providing insights for clinicians to be aware of the possibility of AMI following COVID-19 vaccination and potential underlying mechanisms.