Stenting in Primary Percutaneous Coronary Intervention for Acute ST-Segment Elevation Myocardial Infarction

Outcomes of patients with acute ST-segment elevation myocardial infarction treated by a prolonged “Deferred” percutaneous coronary intervention strategy

BACKGROUND

Primary percutaneous coronary intervention (PCI) is the preferred treatment for ST-segment elevation myocardial infarction (STEMI). However, in patients with high thrombus burden, immediate stenting during PCI can lead to poor outcomes due to the risk of thrombus migration and subsequent microvascular occlusion, resulting in no-reflow phenomena. Deferred stenting offers a potential advantage by allowing for the reduction of thrombus load, which may help to minimize the incidence of slow-flow and no-reflow complications. This study explores the effectiveness of a deferred stenting strategy in improving outcomes for STEMI patients.

AIM

To evaluate the effectiveness and safety of deferred PCI in a real-world setting in acute STEMI patients.

METHODS

This study was conducted at King George’s Medical University, Lucknow, from October 1, 2018, to October 30, 2019 and included a total of 55 participants. Patients with acute STEMI who underwent coronary angiography were selected for a deferred PCI strategy based on specific angiographic features.

RESULTS

Anterior wall myocardial infarction was the predominant type of STEMI in 62% of the selected 55 patients (mean age: 54 years; 70% males), and diabetes mellitus was the most common risk factor (18.2%), followed by hypertension (16.2%). On the second angiogram of these patients measures of thrombus grade, thrombolysis in myocardial infarction flow grade, myocardial blush grade, and severity of stenosis of culprit lesion were considerably improved compared to the first angiogram, and the average culprit artery diameter had increased by 7.8%. Most patients (60%) had an uneventful hospital stay during the second angiogram and an uneventful intraprocedural course (85.19%), with slow-flow/no-reflow occurring only in 7.4% of the patients; these patients recovered after taking vasodilator drugs. In 29.3% of patients, the culprit artery was recanalized, preventing unnecessary stent deployment.

CONCLUSION

Deferred PCI strategy is safe and reduces the thrombus burden, improves thrombolysis in myocardial infarction (TIMI) flow, improves myocardial blush grade, and prevents unwarranted stent deployment.

Downregulation of Gldc attenuates myocardial ischemia reperfusion injury in vitro by modulating Akt and NF-κB signalings

Myocardial ischemia/reperfusion injury (MIRI) is a serious clinical complication that is caused by reperfusion therapy following myocardial infarction (MI). Mitochondria-related genes (Mito-RGs) play important roles in multiple diseases. However, the role of mitochondria-related genes in MIRI remains largely unknown. The GSE67308 dataset from the GEO database was utilized to identify MIRI-related gene modules through WGCNA. Meanwhile, differential expression analysis was conducted to identify differentially expressed genes (DEGs) in the GSE61592 dataset. Next, candidate Mito-RGs related to MIRI were screened by Venn analysis. Thereafter, a myocardial hypoxia/reperfusion (H/R) H9C2 cell model and a mouse ischemia/reperfusion (I/R) model were established to verify the expression level of glycine decarboxylase (Gldc) in MIRI in vitro and in vivo. Based on data from the GEO database, Gldc levels were notably upregulated in murine MIRI samples, compared to the control group. RT-qPCR and western blot confirmed that Gldc levels were obviously elevated in the heart of I/R mice and H/R-exposed cardiomyocytes. Moreover, the deficiency of Gldc notably increased the viability and reduced the apoptosis and inflammatory responses in H9C2 cells exposed to H/R. Meanwhile, Gldc downregulation significantly reduced p-NF-κB p65, Bax and cleaved caspase 3 levels and elevated p-Akt and Bcl-2 levels in H9C2 cells exposed to H/R. The ROC curve analysis further demonstrated that Gldc gene exhibited good diagnostic value for MIRI. Collectively, Gldc deficiency could attenuate H/R injury in cardiomyocytes in vitro through activating Akt and inactivating NF-κB signalings. These data suggested that GLDC may serve as both a diagnostic and therapeutic target for MIRI.

The procedural success of primary angioplasty in a tertiary care center in Pakistan

Objective

This study was conducted to evaluate the procedural success of primary angioplasty in terms of TIMI flow and myocardial blush grade (MBG).

Methods

We used cross-sectional population data of the patients who underwent primary PCI in Emergency Angiography department of Punjab Institute of Cardiology, Lahore from January 2021 to September 2021. TIMI flow and myocardial blush grades (MBG) were assessed before and after the procedure. All PCIs in which there was improvement in blood flow in infarct related artery of ≥2 grades in TIMI flow and/or in MBG were considered successful.

Results

A total of 106 patients were enrolled, 91 patients were male and 15 patients were female with the age range from 22 to 75 (48.7 ± 11.8) years. TIMI flow and MBG was improved ≥ 2 grades in 69 and 58 patients respectively. Improvement in TIMI flow was noted similar in all three vessels. Overall 65% patients showed improvement in TIMI flow and 55% in MBG. Onset of chest pain to balloon time was the most important parameter, shorter the time better the result. The patients in whom MBG was improved, the time was 234.26 ± 156.06 vs 323.59 ± 252.64 minutes.

Conclusion

Primary angioplasty is quite effective procedure for the restoration of blood flow in acute ST elevation myocardial infarction but still it is far away from the ideal one. Although most patients benefit from primary PCI, a significant minority of individuals do not, particularly if they present late. What could be the ideal therapy, the answer is still to be answered.

Postdilatation after stent deployment during primary percutaneous coronary intervention: a systematic review and meta-analysis

BACKGROUND

The utilization of postdilatation in primary percutaneous coronary intervention (PCI) is feared to induce suboptimal coronary blood flow and compromise the outcome of the patients. This meta-analysis sought to verify whether postdilatation during primary PCI is associated with worse angiographic or long-term clinical outcomes.

METHODS

Systematic literature searches were conducted on PubMed, The Cochrane Library, ClinicalTrials.gov, EBSCO, and Europe PMC on 10 March 2024. Eligible studies reporting the outcomes of postdilatation among ST-segment elevation myocardial infarction patients were included. The primary outcome was no-reflow condition during primary PCI based on angiographic finding. The secondary clinical outcome was major adverse cardiovascular events (MACEs) comprising all-cause death, myocardial infarction, target vessel revascularization (TVR), and stent thrombosis.

RESULTS

Ten studies were finally included in this meta-analysis encompassing 3280 patients, which was predominantly male (76.6%). Postdilatation was performed in 40.7% cases. Postdilatation was associated with increased risk of no-reflow during primary PCI [Odd Ratio (OR) = 1.33, 95% Confidence Interval (CI): 1.12-1.58; P = .001)]. Conversely, postdilatation had a tendency to reduce MACE (OR = 0.70, 95% CI: 0.51-0.97; P = .03) specifically in terms of TVR (OR = 0.41, 95% CI: 0.22-0.74; P = .003). No significant differences between both groups in relation to mortality (OR = 0.58, 95% CI: 0.32-1.05; P = .07) and myocardial infarction (OR = 1.5, 95% CI: 0.78-2.89; P = .22).

CONCLUSIONS

Postdilatation after stent deployment during primary PCI appears to be associated with an increased risk of no-reflow phenomenon after the procedure. Nevertheless, postdilatation strategy has demonstrated a significant reduction in MACE over the course of long-term follow-up. Specifically, postdilatation significantly decreased the occurrence of TVR. Key messages: What is already known on this topic?  Optimizing stent deployment by performing postdilatation during percutaneous coronary intervention (PCI) is essential for long-term clinical outcomes. However, its application during primary PCI is controversial due to the fact that it may provoke distal embolization and worsen coronary blood flow. What this study adds?  In this systematic review and meta-analysis of 10 studies, we confirm that postdilatation during primary PCI is associated with worse coronary blood flow immediately following the procedure. On the contrary, this intervention proves advantageous in improving long-term clinical outcomes, particularly in reducing target vessel revascularization. How this study might affect research, practice, or policy?  Given the mixed impact of postdilatation during primary PCI, this strategy should only be applied selectively. Future research should focus on identifying patients who may benefit from such strategy.

Impact of complete versus culprit-only revascularization on major adverse cardiovascular event in diverse subpopulations

Background: Myocardial infarction management relies on pharmaceuticals and interventions like percutaneous coronary intervention (PCI). While complete PCI has shown noninferiority to culprit-only PCI, its impact on major adverse cardiovascular events (MACE) outcomes in multiple subpopulations has been unknown.Methods: A systematic literature search (from January 2000 to May 2024) identified four relevant randomized controlled trials involving ST-segment elevation myocardial infarction patients. Data analysis employed a random-effects model with inverse variance weighting.Results: MACE risk was significantly lower in males than females undergoing complete PCI compared with culprit-only PCI (hazard ratio: 0.52; 95% CI: 0.39-0.68; p < 0.01; I2 = 53%). Furthermore, complete PCI significantly lowered the risk of MACE outcomes in patients without diabetes and in patients under the 65-year age limit in comparison to culprit-only PCI.Conclusion: Complete PCI reduces MACE risk in male, nondiabetic ST-segment elevation myocardial infarction patients under 65 with multivessel coronary artery disease, necessitating further investigation into outcome differences among different subpopulations.

The impact of centralized coronary stent procurement program on acute myocardial infarction treatments: evidence from China

Background

The advent of coronary stents has resulted in many more many lives being saved from acute myocardial infarction (AMI). However, the high price associated with this method of treatment also imposes a heavy economic burden on healthcare systems. As a country making significant use of coronary stents, in 2021, China introduced a program around this method of treatment grounded in centralized procurement and it is the focus of this paper to assess the impact of this policy on AMI treatments.

Methods

The patients with AMI are selected as the study group, and the patients with pre-cerebral vascular stenosis are selected as the control group, and individual-level medical insurance settlement data are collected from the years 2018, 2019, and 2021. Differences-in-differences methodology is used to analyze the impacts of this program on the probability changes in respect of AMI patients receiving stent therapy, as well as changes relating to cost, length of stay and 30-day readmission.

Results

The results show that the reform has led to a reduction in the probability of AMI patients using stents to 51% of the original rate. Additionally, the average cost is shown to have decreased by 41%, and no significant changes can be found in respect of the length of stay and 30-day readmission.

Conclusion

In sum, the centralized procurement program is shown to reduce not only the medical expenses incurred by treating patients with AMI, but also the use of coronary stents, resulting in changes to the treatment patterns of patients with AMI.

Comprehensive Analysis of the COVID-19 Pandemic's Impact on the Prevalence of Acute Coronary Syndrome (ACS)

The COVID-19 pandemic has caused havoc in the world's healthcare systems. Acute coronary syndrome (ACS) admission rates have varied considerably during the pandemic. Even though the coronavirus disease 2019 (COVID-19) pandemic has resulted in fewer acute coronary syndromes (ACS) patients being admitted to hospitals worldwide, clinical characteristics of those patients have not yet been thoroughly examined. Investigating the incidence, clinical presentation, and outcomes of patients with ACS during the COVID-19 pandemic is the goal of the chapter.

ST-segment elevation myocardial infarction heart of Charlotte one-year (STEMI HOC-1) study: a prospective study protocol

BACKGROUND

ST-segment elevation myocardial infarction (STEMI) is a clinically distinguishable yet lethal sequela of ischaemic heart disease (IHD). In sub-Saharan Africa (SSA), death due to acute STEMI is increasing. In South Africa, there is a paucity of data available on the clinical outcomes of acute STEMI within one year for individuals treated in the public healthcare sector. This study primarily seeks to determine the one-year all-cause mortality rate of acute STEMI. The study also assesses the value of serum cardiac biomarkers of myocardial damage and serum uric acid in predicting all-cause mortality in STEMI.

METHODS

This is a single-centre observational prospective cohort of all consecutive individuals presenting with an acute STEMI to the Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in Johannesburg, South Africa. Research data will be sourced on admission through electronic medical records, blood laboratory results and coronary angiography reports, and at follow-up through periodic telephonic interviews and standardised echocardiograms. At least 355 eligible participants will be continuously followed over one year, and clinical outcomes will be measured 30 days, three months, six months and one year after the index hospitalisation.

DISCUSSION

This study provides insights into the demographic, risk factors and clinical profiles of individuals with STEMI in South Africa. Its findings may improve the risk stratification, prognostication, and therapeutic management of STEMI patients in our setting. By comparing the clinical outcomes between the different coronary reperfusion strategies, our results may guide clinicians in providing better patient treatment, particularly in sub-Saharan Africa, where access to percutaneous coronary intervention may be limited. Furthermore, the study offers insights into the routine use of baseline serum uric acid as a potential low-cost prognostic biomarker of all-cause mortality in STEMI. Finally, this study's findings may be of public health significance to local policymakers to aid in reinforcing primary prevention strategies and developing structured referral networks for timely coronary reperfusion of acute STEMI.

Rodent Models of Dilated Cardiomyopathy and Heart Failure for Translational Investigations and Therapeutic Discovery

Even with modern therapy, patients with heart failure only have a 50% five-year survival rate. To improve the development of new therapeutic strategies, preclinical models of disease are needed to properly emulate the human condition. Determining the most appropriate model represents the first key step for reliable and translatable experimental research. Rodent models of heart failure provide a strategic compromise between human in vivo similarity and the ability to perform a larger number of experiments and explore many therapeutic candidates. We herein review the currently available rodent models of heart failure, summarizing their physiopathological basis, the timeline of the development of ventricular failure, and their specific clinical features. In order to facilitate the future planning of investigations in the field of heart failure, a detailed overview of the advantages and possible drawbacks of each model is provided.

Relationship between Admission Electrolyte Level and Short-term Prognosis of Patients with Acute ST-segment Elevation Myocardial Infarction after Percutaneous Coronary Intervention

OBJECTIVE

The objective of this study is to analyze the relationship between the electrolyte level of patients with acute ST-segment elevation myocardial infarction (STEMI) and short-term prognosis after percutaneous coronary intervention (PCI).

METHODS

The clinical data of 142 patients with acute STEMI who underwent PCI in our hospital from September 2018 to September 2019 were retrospectively analyzed. According to the level of serum sodium, potassium, and chloride in patients admitted to the hospital, they were divided into the normal electrolyte group (n = 78), the mild decline group (n = 46), and the severe decline group (n = 16). Univariate and logistic regression multivariate analysis of the relationship between patient electrolyte levels and general clinical data is performed. Statistical analysis of patients' adverse events within 90 days was performed. The Kaplan-Meier survival curve analyzed the relationship between the survival period and electrolyte levels in patients with acute STEMI without major acute cardiovascular events (MACE) within 90 days.

RESULTS

The levels of creatine kinase-MB (CK-MB), cardiac troponin I (cTnI), myocardial infarction area, and Gensini score in patients with mild decline were significantly higher than those in the normal group, left ventricle ejection fractions (LVEF) value was significantly lower than the normal group, and patients with severe decline were significantly higher in creatine kinase (CK) level than the normal group (P < 0.05). The levels of CK-MB, CK, cTnI, and myocardial infarction area of the patients in the severe decline group were significantly higher than those in the mild decline group, and the LVEF values were significantly lower than those in the mild decline group (P < 0.05). The levels of CK-MB, CK, cTnI, the area of myocardial infarction, and Gensini score in patients with acute STEMI have an independent effect on their electrolyte levels. The patients in the mild decline group and severe decline group had significantly higher rates of cardiogenic shock, heart failure, ventricular aneurysm formation, ventricular septal perforation, or death within 90 days after PCI. The median without MACE survival time of patients with mildly and severely reduced electrolyte levels was significantly lower than that of patients with normal electrolyte levels.

CONCLUSION

Patients with acute STEMI are prone to electrolyte disturbances, and their CK-MB, CK, and cTnI levels; myocardial infarction area; and Gensini score have independent effects on electrolyte levels. Patients with electrolyte disturbances are prone to poor prognosis after PCI, and their survival period without MACE at 90 days is significantly lower than that of normal patients.

The application of whole-course nursing in patients undergoing emergency PCI and its impact on cardiac function

OBJECTIVE

To implement whole-course care in patients undergoing emergency percutaneous coronary intervention and investigate its impact on cardiac function.

METHODS

This study included 88 acute myocardial infarction patients undergoing percutaneous coronary intervention. These patients were randomly divided into the control group (n=44, which underwent routine care) and the experimental group (n=44, which underwent whole-course care). The cardiac function, physiological states, quality of life, complications, and the patient satisfaction with the care were compared between the two groups.

RESULTS

Compared with before the surgery, the left ventricular ejection fractions and the cardiac output in both groups at discharge were increased, while the left ventricular end-systolic diameters and left ventricular end-diastolic diameters were decreased (all P<0.05). In addition, the changes in the experimental group were greater than they were in the control group (all P<0.05). The HAMA and HAMD scores in the two groups at discharge were decreased compared with before the surgeries, but the GQOLI-74 scores in all aspects were increased (all P<0.05). Similarly, the changes in the experimental group were greater than those in the control group (all P<0.05). The incidence of postoperative complications in the experimental group was lower than it was in the control group, and the satisfaction with care was higher than it was in the control group (both P<0.05).

CONCLUSIONS

The whole-course care of AMI patients undergoing PCI can significantly relieve their negative emotions, improve their cardiac function, increase their quality of life, and reduce their incidences of complications.

Investigation of the value of carotid-femoral pulse wave velocity and coronary artery lesions in prognosis of percutaneous coronary intervention patients

OBJECTIVE

To investigate the value of carotid-femoral pulse wave velocity (CFPWV) and coronary artery lesions in assessing prognosis of percutaneous coronary intervention (PCI) patients.

METHODS

A total of 300 PCI patients admitted to our hospital were selected as study subjects, and were divided into Group A (0-13 m/s, n=180) and Group B (> 13 m/s, n=120) in accordance with different carotid-femoral pulse wave velocities (CFPWVs). Coronary artery lesions, incidence rates of major adverse cardiac events (MACE) at different stages, and differences in the indexes of cardiac function were compared between the two groups.

RESULTS

Compared to Group A, Group B had more severe coronary artery lesions and higher incidence rates of postoperative complications and MACE during hospital stay and 2-year follow-up (P < 0.05). At 1 month after surgery, the left ventricular stroke volume, left ventricular end-diastolic volume and left ventricular ejection fraction in Group A were higher than those of Group B. CFPWV was significantly correlated with Gensini score (GS) and incidence rate of MACE (P < 0.05), and the differences in the area under curve (AUC) of CFPWV for predicting the incidence rate of MACE were significant (P < 0.05).

CONCLUSION

CFPEV, exhibits value in assessing the prognosis of PCI patients, and can effectively predict the postoperative incidence of MACE, which is conducive to the establishment of subsequent regimens. Therefore, CFPEV is worthy of clinical promotion and implementation.

A nomogram for predicting the risk of no-reflow after primary percutaneous coronary intervention in elderly patients with ST-segment elevation myocardial infarction

Background

The purpose of this study was to screen the predictive factors of no-reflow after a percutaneous coronary intervention (PCI) in elderly patients with ST-segment elevation myocardial infarction (STEMI), and to construct a nomogram model, to guide clinical treatment.

Methods

A total of 551 elderly STEMI patients (age >65) underwent direct PCI were randomly classified into training group (n=386, 70%) and validation group (n=165, 30%). All patients in the two groups were divided into a no-reflow group and a normal blood flow group according to whether there was a no-reflow phenomenon. Univariable and multivariable logistic regression analysis was used to analyze the relevant data, including demographic characteristics, clinical characteristics, coronary angiography results, electrocardiogram (ECG) results, and biochemical indicators. Then, a nomogram model was constructed on the screened risk factors. The performance of the nomogram was evaluated in terms of discrimination and calibration. The nomogram was further confirmed in the internal validation group. Additionally, decision curve analysis (DCA) was applied to assess the clinical usefulness of the nomogram.

Results

Five remarkable risk factors were determined: preoperative TIMI blood flow, the diameter of the target lesion, collateral circulation, pulse pressure, and the number of leads for ST-segment elevation. The nomogram involving these five risk factors showed full calibration and discrimination in the training group, with an AUC of 0.71 (95% CI: 0.66–0.77). It was confirmed in the validation group, and the entire cohort and the AUC were 0.64 (95% CI: 0.56–0.73) and 0.69 (95% CI: 0.65–0.74), respectively. Whether in the training group or the verification group, the calibration curve for the probability of no-reflow phenomenon all showed considerable consistency between prediction by nomogram and actual observation. The decision curve revealed a specific role in our nomogram in clinical practice.

Conclusions

We set up a nomogram that showed absolute accuracy for the prediction of the risk of no-reflow after primary PCI in elderly STEMI patients.

[Effect of Myocardial Reperfusion on Ischemic Mitral Regurgitation in Patients with Acute Myocardial Infarction]

BACKGROUND

During the restoration of blood flow in the ischemic area of the myocardium, viable cardiomyocytes are damaged over a few minutes of tissue reperfusion (reperfusion myocardial damage). It is known that ischemic mitral regurgitation (IMR) develops in 11-19 % of patients who have undergoing percutaneous coronary intervention (PCI) in symptomatic coronary heart disease (CHD). To present day, the influence of myocardial reperfusion on IMR in patients with acute myocardial infarction (AMI) is not fully understood.

OBJECTIVE

To study dynamics of quantitative indicators of IMR in patients with AMI after myocardial reperfusion.

MATERIALS AND METHODS

We included in this study 68 patients with AMI and IMR aged 36-79 years, who were hospitalized in cardiac intensive care unit of the Moscow S. S. Yudin hospital in 2016. All patients before and on the 7th day after PCI underwent doppler echocardiography study with calculation of quantitative parameters of IMR and index of local contractility (ILC) of the left ventricle (LV).

RESULTS

Three groups of patients were identified based on the analysis of the dynamics of quantitative parameters of IMR after myocardial reperfusion: group 1 - patients who had a decrease in IMR (n=23, 33.8 %), group 2 - patients with increase of IMR (n=28, 41.1 %), group 3 - patients with unchanged IMR (n=17, 25.1 %). The study of systolicLV function in all patients before PCI revealed moderately decreased ejection fraction (EF) (mean 49.05±1.19 %). On day 7 after myocardial reperfusion in group 2 we detected significant increases of end-diastolic volume (EDV), end-systolic volume (ESV), and the volume of the left atrium (LA), while in groups 1 and 3 these indexes remained unchanged. LV ILC did not differ between three groups, both at admission and on day 7 after reperfusion (p&gt;0.05). There was no correlation between severity of IMR and ILC (correlation coefficient 0.24).

CONCLUSION

Dynamics of quantitative parameters of IMR in 7 days after myocardial reperfusion in patients with AMI without endogenous and drug protection of the myocardium from reperfusion injury was multidirectional. IMR decreased in 33.8, increased in 41.1 and did not change in 25.1 % of patients. Systolic function and LV ILC underwent no significant dynamics.

Protective effect of Barbaloin in a rat model of myocardial ischemia reperfusion injury through the regulation of the CNPY2‑PERK pathway

Barbaloin (Bar) has a myocardial protective effect, but its mechanism of action is uncertain. The endoplasmic reticulum stress (ERS)-mediated apoptosis pathway serves an important role in the pathogenesis of myocardial ischemia-reperfusion injury (MIRI). Inhibiting ERS may significantly improve the progression of MIRI and serve a role in its prevention. Therefore, based on current knowledge of ERS-mediated cardiomyocyte apoptosis and the cardioprotective effect of Bar, the purpose of the present study was to further evaluate the myocardial protective effect and potential mechanisms of Bar pretreatment in MIRI. The present study established a MIR rat model and randomly divided these rats into four groups. Prior to myocardial ischemia, Bar (20 mg/kg) was administered to rats once daily for 1 week. Myocardial blood serum lactate dehydrogenase and creatine kinase were subsequently measured. A terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay was used to evaluate the myocardial protective effect of Bar pretreatment on MIRI. To assess whether the ERS signaling pathway was involved in the myocardial protection mechanism of Bar pretreatment, the expression levels of ERS-associated proteins, protein canopy homolog 2 (CNPY2), glucose regulatory protein 78, transcriptional activator 4, C/EBP-homologous protein (CHOP), PKR endoplasmic reticulum kinase (PERK), caspase-12 and caspase-3 were detected by western blot analysis, immunohistochemistry or reverse transcription-quantitative polymerase chain reaction. The results confirmed that Bar pretreatment significantly reduced the damage and the level of apoptosis caused by MIR. Bar pretreatment significantly inhibited the expression of ERS-associated proteins in cardiomyocytes. In addition, the immunohistochemistry results demonstrated that Bar pretreatment significantly inhibited the CNPY2-positive cell apoptosis ratio of cardiomyocytes. Therefore, the results of the current study suggested that CNPY2 is present in cardiomyocytes and participates in the development of MIRI by initiating the PERK-CHOP signaling pathway. Bar pretreatment may attenuate MIRI by inhibiting the CNPY2-PERK apoptotic pathway.