Efficacy of clotinab in acute myocardial infarction trial-ST elevation myocardial infarction (ECLAT-STEMI)

The promotion of sestrin2/AMPK signaling by HIF-1α overexpression enhances the damage caused by acute myocardial infarction

OBJECTIVE

Acute myocardial infarction (AMI), is a serious form of coronary heart disease. The present study sought to investigate the impact of HIF-1α on AMI, along with its fundamental mechanism.

METHODS

Sprague-Dawley (SD) rats were used to conduct an AMI model. 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining was used examine the region of myocardial infract area at various time intervals. Protein expression levels were detected using western blotting. The rats were randomly divided into sham, model, negative control (NC), HIF-1α overexpression (HIF-1α-OE), and HIF-1α-OE+ si-sestrin2 groups. We examined the impact of HIF-1α overexpression on AMI rats using Haematoxylin-Eosin (H&E) staining, TTC staining, enzyme-linked immunosorbent assay (ELISA), TdT-mediated dUTP Nick-End Labeling (TUNEL) assay, and immunohistochemistry (IHC) staining.

RESULTS

According to the TTC findings, the region affected by myocardial infarction reached its peak at day 14. Based on the results from the western blot analysis, the levels of HIF-1α and sestrin2 were found the minimum on day 28. Subsequently, we discovered that the overexpression of HIF-1α rescued the cardiac function parameters, improved the morphology of myocardial tissue, and mitigated inflammation. Furthermore, the overexpression of HIF-1α led to a reduction in the levels of MDA and an increase in the levels of SOD. Moreover, the overexpression of HIF-1α resulted in a decrease in cellular apoptosis. This result was confirmed by the expression levels of Bcl-2 and Bax. Nevertheless, the defensive impact of elevated HIF-1α expression was somewhat counteracted by the suppression of sestrin2. In terms of mechanism, the overexpression of HIF-1α enhanced the levels of sestrin2 and the protein adenosine monophosphate activated kinase (AMPK).

CONCLUSION

Our research suggests that the overexpression of HIF-1α may rescue the damage to myocardial tissue, and this effect is associated with the sestrin2/AMPK signaling pathway. Our study provides a novel comprehension of the protective effects of HIF-1α overexpression on AMI.

Role of ST-Segment Resolution Alone and in Combination With TIMI Flow After Primary Percutaneous Coronary Intervention for ST-Segment-Elevation Myocardial Infarction

Background To evaluate the role of ST-segment resolution (STR) alone and in combination with Thrombolysis in Myocardial Infarction (TIMI) flow in reperfusion evaluation after primary percutaneous coronary intervention (PPCI) for ST-segment-elevation myocardial infarction by investigating the long-term prognostic impact. Methods and Results From January 2013 through September 2014, we studied 5966 patients with ST-segment-elevation myocardial infarction enrolled in the CAMI (China Acute Myocardial Infarction) registry with available data of STR evaluated at 120 minutes after PPCI. Successful STR included STR ≥50% and complete STR (ST-segment back to the equipotential line). After PPCI, the TIMI flow was assessed. The primary outcome was 2-year all-cause mortality. STR < 50%, STR ≥50%, and complete STR occurred in 20.6%, 64.3%, and 15.1% of patients, respectively. By multivariable analysis, STR ≥50% (5.6%; adjusted hazard ratio [HR], 0.45 [95% CI, 0.36-0.56]) and complete STR (5.1%; adjusted HR, 0.48 [95% CI, 0.34-0.67]) were significantly associated with lower 2-year mortality than STR <50% (11.7%). Successful STR was an independent predictor of 2-year mortality across the spectrum of clinical variables. After combining TIMI flow with STR, different 2-year mortality was observed in subgroups, with the lowest in successful STR and TIMI 3 flow, intermediate when either of these measures was reduced, and highest when both were abnormal. Conclusions Post-PPCI STR is a robust long-term prognosticator for ST-segment-elevation myocardial infarction, whereas the integrated analysis of STR plus TIMI flow yields incremental prognostic information beyond either measure alone, supporting it as a convenient and reliable surrogate end point for defining successful PPCI. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01874691.

2021 Korean Society of Myocardial Infarction Expert Consensus Document on Revascularization for Acute Myocardial Infarction

Acute myocardial infarction (AMI) is a fatal manifestation of ischemic heart disease and remains a major public health concern worldwide despite advances in its diagnosis and management. The characteristics of patients with AMI, as well as its disease patterns, have gradually changed over time in Korea, and the outcomes of revascularization have improved dramatically. Several characteristics associated with the revascularization of Korean patients differ from those of patients in other countries. The sophisticated state of AMI revascularization in Korea has led to the need for a Korean expert consensus. The Task Force on Expert Consensus Document of the Korean Society of Myocardial Infarction has comprehensively reviewed the outcomes of large clinical trials and current practical guidelines, as well as studies on Korean patients with AMI. Based on these comprehensive reviews, the members of the task force summarize the major guidelines and recent publications, and propose an expert consensus for revascularization in patients with AMI.

Gambogic acid exerts cardioprotective effects in a rat model of acute myocardial infarction through inhibition of inflammation, iNOS and NF-κB/p38 pathway

Gamboge, the dried resin secreted by Garcinia maingayii (gambogic tree), was previously demonstrated to exert anti-inflammatory effects. The present study examined the effects of gambogic acid, the major active constituent of gamboge, on myocardial infarction (MI) and inflammation in a rat model and explored the possible underlying mechanisms. The results demonstrated that gambogic acid inhibited the ratio of heart weight to body weight and myocardial damage (via lactate dehydrogenase and cardiac troponin T) in rats with MI. Gambogic acid suppressed the activation of interleukin (IL)-6 and tumor necrosis factor-α, and increased IL-10 levels in MI rats. Furthermore, gambogic acid reduced inducible nitric oxide synthase (iNOS), matrix metalloproteinase (MMP)-2, MMP-9, intercellular adhesion molecule-1 (ICAM-1), nuclear factor (NF)-κB/p65 and phosphorylated p38 protein in ischemic myocardial tissue of MI rats. In conclusion, gambogic acid exerted anti-inflammatory effects in MI rats by targeting the iNOS, MMPs, ICAM-1, NF-κB and p38 pathways. Gambogic acid may protect against MI-induced inflammation in rats, which may be associated with the activation of the NF-κB/p38 pathway.

The impact of vascular access for in-hospital major bleeding in patients with acute coronary syndrome at moderate- to very high-bleeding risk

The aim of our study was to determine the impact of vascular access on in-hospital major bleeding (IHMB) in acute coronary syndrome (ACS). We analyzed 995 patients with non-ST elevation myocardial infarction and unstable angina at the Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the ACC/AHA guidelines (CRUSADE) moderate- to very high-bleeding risk scores in trans-radial intervention (TRI) retrospective registry from 16 centers in Korea. A total of 402 patients received TRI and 593 patients did trans-femoral intervention (TFI). The primary end-point was IHMB as defined in the CRUSADE. There were no significant differences in in-hospital and 1-yr mortality rates between two groups. However, TRI had lower incidences of IHMB and blood transfusion than TFI (6.0% vs 9.4%, P = 0.048; 4.5% vs 9.4%, P = 0.003). The patients suffered from IHMB had higher incidences of in-hospital and 1-yr mortality than those free from IHMB (3.1% vs 15.0%, P < 0.001; 7.2% vs 30.0%, P < 0.001). TRI was an independent negative predictor of IHMB (odds ratio, 0.305; 95% confidence interval, 0.109-0.851; P = 0.003). In conclusions, IHMB is still significantly correlated with in-hospital and 1-yr mortality. Our study suggests that compared to TFI, TRI could reduce IHMB in patients with ACS at moderate- to very high-bleeding risk.

Implementation of standardized assessment and reporting of myocardial infarction in contemporary randomized controlled trials: a systematic review

Myocardial infarction (MI) is a key endpoint in randomized controlled trials (RCTs), but heterogeneous definitions limit comparisons across RCTs or meta-analyses. The 2000 European Society of Cardiology/American College of Cardiology MI redefinition and the 2007 universal MI definition consensus documents made recommendations to address this issue. In cardiovascular randomized trials, we evaluated the impact of implementation of three key recommendations from these reports-troponin use to define MI; separate reporting of spontaneous and procedure-related MI; and infarct size reporting. We searched ClinicalTrials.gov and MEDLINE databases for cardiovascular RCTs with more than 500 patients in which enrolment began between September 2000 and July 2012 and that listed MI in the primary endpoint. We searched English-language publications with primary results or design papers. Of 3222 studies screened, 96 (3.0%) met our criteria. We extracted enrolment start date, number of patients and MI events, follow-up duration, and coronary revascularization rate. Data extraction quality was assessed by duplicated extractions. Of 96 RCTs, 80 had a primary results publication, comprising 608 091 patients and 43 621 endpoint MIs. Myocardial infarction represented 45.3% (95% confidence interval, 40.2-50.4) of events in the primary composite endpoint. Troponin defined MI in 57% (53/93) of trials with an MI definition available. Of these RCTs, three used troponin only if creatine kinase-MB was unavailable, six used troponin to define peri-procedural MI, seven specified the 99th percentile as the MI decision limit, and three reported spontaneous and procedure-related MI separately. None reported biomarker-based infarct size, but five reported MI as multiples of the assay upper limit of normal. Although MI is a major component of cardiovascular RCT primary endpoints, standardized MI reporting and implementation of consensus document recommendations for MI definition are limited. Developing appropriate strategies for uniform implementation is required.