Effect of COVID-19 outbreak on the treatment time of patients with acute ST-segment elevation myocardial infarction

ObjectiveTo explore the effect of COVID-19 outbreak on the treatment time of patients with ST-segment elevation myocardial infarction (STEMI) in Hangzhou, China.MethodsWe retrospectively reviewed the data of STEMI patients admitted to the Hangzhou Chest Pain Center (CPC) during a COVID-19 epidemic period in 2020 (24 cases) and the same period in 2019 (29 cases). General characteristics of the patients were recorded, analyzed, and compared. Moreover, we compared the groups for the time from symptom onset to the first medical contact (SO-to-FMC), time from first medical contact to balloon expansion (FMC-to-B), time from hospital door entry to first balloon expansion (D-to-B), and catheter room activation time. The groups were also compared for postoperative cardiac color Doppler ultrasonographic left ventricular ejection fraction (LVEF),the incidence of major adverse cardiovascular and cerebrovascular events (MACCE),Kaplan-Meier survival curves during the 28 days after the operation.ResultsThe times of SO-to-FMC, D-to-B, and catheter room activation in the 2020 group were significantly longer than those in the 2019 group (P < 0.05). The cumulative mortality after the surgery in the 2020 group was significantly higher than the 2019 group (P < 0.05).ConclusionThe pre-hospital and in-hospital treatment times of STEMI patients during the COVID-19 epidemic were longer than those before the epidemic. Cumulative mortality was showed in Kaplan-Meier survival curves after the surgery in the 2020 group was significantly different higher than the 2019 group during the 28 days.The diagnosis and treatment process of STEMI patients during an epidemic should be optimized to improve their prognosis.     

Risk stratification after ST-segment elevation myocardial infarction

Introduction: Risk stratification according to the timing of assessment, treatment modality and outcome of interest is highly advisable in patients with ST-elevation myocardial infarction (STEMI) to identify optimal treatment strategies, proper length of hospital stay and correct timing of follow-up.

Areas covered: This review is an overview summarizing the characteristics and performance of available risk-scoring systems for STEMI. In particular, we sought to highlight the characteristics of STEMI cohorts used for derivation and validation of the available algorithms and appraise their discrimination ability, calibration and global accuracy.

Expert commentary: Applying the appropriate score, customized on patients’ profile and clinical characteristics at presentation or during the hospitalization, might prove useful to improve the overall quality of care provided to STEMI patients.     

The challenge of ST-segment elevation myocardial infarction

BACKGROUND/INTRODUCTION: Acute coronary syndromes (ACS) represent a spectrum of ischaemic myocardial events that share a similar pathophysiology. ST-segment elevation myocardial infarction (STEMI), the most severe form of ACS short of sudden cardiac death, is a significant public health problem with an estimated 500,000 STEMI events every year in the United States. TREATMENT/THERAPY: The mortality and morbidity associated with STEMI is significant. Early reperfusion therapy is the most important aspect of the treatment of STEMI. There are two main methods of reperfusion therapy: percutaneous coronary intervention (PCI) and fibrinolytic therapy, with PCI being the preferred method. In addition to standard reperfusion therapy, antithrombotics (unfractionated heparin and low molecular weight heparins) and antiplatelet agents (aspirin, clopidogrel and glycoprotein IIb/IIIa inhibitors) are critical adjuncts, effective in the treatment of acute STEMI. CONCLUSIONS: The survival of patients with STEMI depends on rapid diagnosis and optimal early treatment. Guidelines for the management of patients with STEMI recommend PCI within 90 min of presentation and that fibrinolytics are administered within 30 min. However, only a fraction of patients undergo reperfusion within the recommended time. Improvements in protocols for identifying STEMI cases are therefore required to allow reperfusion therapy to be initiated sooner. Secondary prevention is another important aspect of STEMI management, and patients should be encouraged to adopt strategies that reduce the risk of subsequent ischaemic events.     

Management of ST-segment elevation myocardial infarction in EDs

Emergency department (ED) physicians are critical in the accurate diagnosis, efficient management, and treatment of patients with ST-segment elevation myocardial infarction. The initial reperfusion strategy involves the choice between mechanical reperfusion using primary percutaneous coronary intervention and pharmacologic treatment with fibrinolytics. The benefits of these approaches are time dependent, and practices vary according to institutional resources and local guidelines. Nevertheless, the need for early intervention and the use of certain therapies are well recognized. Therefore, ED physicians must be aware of all treatment options available, including the use of adjunctive therapies. Initial treatment should include beta-blockers, aspirin (or clopidogrel if aspirin is contraindicated), nitroglycerin, and analgesia, regardless of reperfusion strategy. Clopidogrel is now approved as an adjunctive therapy for patients undergoing fibrinolysis as their reperfusion therapy. Both unfractionated heparin and low-molecular-weight heparin are feasible adjunctives in patients with ST-segment elevation myocardial infarction undergoing reperfusion therapy. In addition, multiple new antithrombin agents are being investigated. The choice adjunctive treatments should be based on specific patient populations and on the initial reperfusion strategy.     

替罗非班对伴缺血性J波急性ST段抬高型心肌梗死心电图的影响

目的:评价替罗非班对伴缺血性J波的急性ST段抬高型心肌梗死急诊介入治疗期间心电图的影响并对其近期预后进行评估。方法:将45例12 h内发生的伴缺血性J波的急性ST段抬高型心肌梗死并行急诊PCI的患者分为替罗非班治疗组(治疗组)和非替罗非班治疗组(对照组),疗程24~48 h。观察围手术期心电图缺血性J波、ST-T的变化和心律失常的发生及MACE发生情况。结果:治疗组心电图出现的J波在术后2 h内全部消失,抬高的J点与ST段较对照组在术后早期即明显回落,术中及术后恶性室性心律失常的发生率明显降低(P<0.05)。结论:替罗非班可以明显改善心电图上出现的缺血性J波,显著降低术中及术后恶性室性心律失常的发生率,提高介入治疗成功率,降低术后近期死亡率。     

新型冠状病毒肺炎疫情管控对诊治急性ST段抬高心肌梗死患者的影响

目的 探讨新型冠状病毒肺炎(COVID-19)疫情管控对诊治急性ST段抬高心肌梗死(STEMI)患者的影响.方法 选取我院2019年2月至3月非COVID-19流行期收治的STEMI患者37例(A组)、2020年2月至3月COVID-19流行初期收治的STEMI患者23例(B组)、2020年4月至5月COVID-19防...     

急性ST段抬高型心肌梗死的非典型心电图改变

心电图是广泛使用和容易获得的最初诊断工具。急性心肌梗死（AMI）的治疗有赖于其临床表现、心电图及心肌坏死标志物的综合判断。识别高危心电图及其微妙变化将使患者早期血运重建明显获益。本文主要对非典型的心电图诊断相当于急性ST段抬高型心肌梗死（STEMI）的一些规律,包括左束支传导阻滞（LBBB）满足Sgarbossa标准、Wellens′综合征、QRS波终末变形、超急性T波、de Winter征和aVR导联抬高等进行综述。     

Acute ST-segment elevation myocardial infarction: critical care perspective

More than 1.2 million patients suffer from new or recurrent ischemic events occur annually. This includes an estimated 565,000 cases of first and 300,000 cases of recurrent myocardial infarction (MI). Although mortality from acute MI has declined in recent years, it still remains high at 25% to 30%. Despite its high mortality, prognosis can be improved with timely and effective use of evidence-based treatment in the acute setting. This review outlines the critical care management strategies for ST-segment MI (STEMI).     

The evolution of electrocardiographic changes in ST-segment elevation myocardial infarction

Acute myocardial infarction (AMI) is a not uncommon diagnosis in the emergency department. During ST-segment elevation AMI (STEMI), the electrocardiogram (ECG) typically follows a progression of abnormality, beginning with hyperacute T waves and culminating with ST-segment elevation; pathologic Q waves can appear early and/or late in the process. Other findings include T-wave inversion and ST-segment depression which can occur before, during, or after the STEMI event. The evolution of ECG through these changes can occur rapidly after coronary artery occlusion. The emergency physician should be aware of the ECG findings that characterize the evolution of an STEMI with a sound understanding of the associated pathophysiology and clinical implication. This review discusses the changing ECG during an AMI. The pathogenesis of these findings is discussed. Finally, the clinical implications at each stage are reviewed.     

Reperfusion strategies in the emergency treatment of ST-segment elevation myocardial infarction

Prompt restoration of blood flow is the primary treatment goal in ST-segment elevation myocardial infarction to optimize clinical outcomes. The ED plays a critical role in rapid triage, diagnosis, and management of ST-elevation myocardial infarction, and in the decision about which of the 2 recommended reperfusion options, that is, pharmacologic and mechanical (catheter-based) strategies, to undertake. Guidelines recommend percutaneous coronary intervention (PCI) if the medical contact-to-balloon time can be kept under 90 minutes, and timely administration of fibrinolytics if greater than 90 minutes. Most US hospitals do not have PCI facilities, which means the decision becomes whether to treat with a fibrinolytic agent, transfer, or both, followed by PCI if needed. Whichever reperfusion approach is used, successful treatment depends on the ED having an integrated and efficient protocol that is followed with haste. Protocols should be regularly reviewed to accommodate changes in clinical practice arising from ongoing clinical trials.     

Incidence and predictors of ventricular arrhythmias after ST-segment elevation myocardial infarction

Background

Sustained ventricular arrhythmias (VA) complicate 7% to 20% of acute myocardial infarctions. We hypothesized that primary angioplasty (percutaneous coronary intervention [PCI]) and contemporary medical treatment will result in a lower incidence of VA and shorten the time frame of their occurrence. Thus, an electrocardiographic monitoring period of 24 hours should be sufficient to detect more than 95% of all malignant VA.

Methods

We continuously monitored all patients with ST-segment elevation myocardial infarction (STEMI) for 48 hours.

Results

Of the 510 patients who underwent PCI for STEMI, 24 (4.7%) developed sustained VA. Sixty percent of sustained VA occurred during the first 24 hours; and 92%, during the first 48 hours. In univariate analysis, heart rate greater than 100 beats per minute, Thrombolysis in Myocardial Infarction flow grade less than 3, elevated creatinine (≥1 mg/dL), elevated C-reactive protein (≥0.8 mg/dL), higher white blood cell count (≥12 × 10³/μL), use of diuretics, and lower hematocrit (≤39%) were associated with an increased risk of VA. Symptom-onset-to-balloon time of 4 hours or more in patients with postprocedural Thrombolysis in Myocardial Infarction 3 flow, treatment with β-blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and statins were associated with a reduced risk of VA. After multivariate adjustment, independent predictors of sustained VA included total white blood cell count of 12 × 10³/μL or more, hematocrit of 39% or less, and lack of β-blocker medication.

Conclusions

In this study, we could demonstrate that primary PCI results in a lower incidence of VA compared with data from the literature but did not shorten the time frame of VA occurrence. Thus, an electrocardiographic monitoring period for VA of 48 hours should be performed in patients with STEMI.     

Assessing and managing coronary microcirculation dysfunction in acute ST-segment elevation myocardial infarction

Introduction: Microvascular dysfunction in the setting of acute ST-segment elevation myocardial infarction (STEMI) is an indicator of poor long-term prognosis. Prompt assessment and pharmacological or procedural therapy (prophylactic or post onset of dysfunction) may improve outcomes in STEMI post-primary percutaneous intervention.

Areas covered: The aim of this review is to provide a comprehensive analysis of the evidence available about the assessment and management of coronary microcirculatory injury/dysfunction in STEMI. We also aim to elucidate the possible strategies that could be applied in clinical practice to support the application of already available or novel therapeutic strategies for the prevention and management of microvascular impairment.

Expert commentary: There are multiple established methods in assessing microvascular dysfunction, both non-invasively and invasively. Invasive physiological measurements allow real-time assessment of microvascular dysfunction and have prognostic cut-off values. Multiple therapeutic modalities exist for both preventing and treating microvascular dysfunction. These can be either pharmacological or mechanical, and there is no algorithm to guide if, how and when to apply them. Future research into both procedural and pharmacological therapy guided by physiological measurements is needed, with the aim of recognizing high-risk patients who would benefit from therapy.     

ST段抬高型心肌梗死患者循环微RNA-92a表达的研究

目的 了解微RNA-92a(miR-92a)在ST段抬高型心肌梗死(STEMI)发生发展中的表达,以及经皮冠状动脉介入治疗(PCI)对循环miR-92a表达的影响,探讨miR-92a在冠心病临床应用中的可能性.方法 82例STEMI患者及116例慢性稳定型心绞痛(SAP)患者按照是否接受PCI治疗分为STEMI行PCI治疗组(58例)、STEMI未行PCI治疗组(24例)及SAP未行PCI治疗组(116例)3组,分析比较其循环miR-92a表达的差异.结果 STEMI未行PCI患者入院次日循环miR-92a表达水平高于SAP未行PCI者(0.286 9±0.816 7比-0.055 5±0.985 5,P=0.121).PCI治疗24 h后STEMI行PCI患者循环miR-92a表达水平低于STEMI未行PCI者(-0.032 4±0.956 3比0.286 9±0.816 7,P=0.156).SAP未行PCI患者出院存活率显著高于STEMI未行PCI者(100.0％比75.0％,P=0.001),STEMI行PCI患者出院存活率高于STEMI未行PCI者(89.7％比75.0％,P=0.088).结论 STEMI患者循环miR-92a表达增高;PCI治疗能降低STEMI患者循环miR-92a表达;miR-92a表达下调的STEMI患者出院时存活率高于表达上调的STEMI患者.miR-92a很可能具有用于诊断或评估STEMI危险度、提高急性心肌梗死高危患者筛选的敏感性与准确性以及进行干预治疗的临床实际应用价值.     

心脏核磁共振成像对缺血后处理急性ST段抬高型心肌梗死后心室重塑的影响

目的探讨心脏核磁共振成像（CMR）对缺血后处理急性ST段抬高型心肌梗死（STEMI）后心室重塑的影响。方法选择32例12h内行缺血后处理的STEMI患者作为实验组及12例健康志愿者作为对照组。2组均于术后6个月行CMR检查,测量左室心功能指标及梗死心肌面积所占百分比,并以24％为分界值,将实验组又分为无重塑组和重塑组。分析各组间的心功能参数差异,并进行受试者工作特征（ROC）分析。结果与对照组比较,无重塑组与重塑组患者的舒张末期容积（EDV）、收缩末期容积（ESV）和每搏输出量（SV）均明显增加,而射血分数（EF）、PER和PFR均有不同程度的下降,其中重塑组下降的幅度更为显著。ESV与EDV的增大呈线性关系;PFR、PER和EF均随EDV的增大而呈线性下降趋势。ROC分析结果显示,EDV、ESV、EF和PFR的曲线下面积分别为0．741、0．764、0．713和0．743。结论CMR对预测心室重塑有重要作用,其中PFR、ESV和EDV可作为独立因子预测心室重塑。     

Prehospital system delay in patients with ST-segment elevation myocardial infarction in Singapore

BACKGROUND: Timely reperfusion in ST-segment elevation myocardial infarction(STEMI)improves outcomes. System delay is that between first medical contact and reperfusion therapy,comprising prehospital and hospital components. This study aimed to characterize prehospital system delay in Singapore.METHODS: A retrospective chart review was performed for 462 consecutive STEMI patients presenting to a tertiary hospital from December 2006 to April 2008. Patients with cardiac arrest secondarily presented were excluded. For those who received emergency medical services(EMS),ambulance records were reviewed. Time intervals in the hospital were collected prospectively. The patients were divided into two equal groups of high/low prehospital system delay using visual binning technique.RESULTS: Of 462 patients, 76 received EMS and 52 of the 76 patients were analyzed. The median system delay was 125.5 minutes and the median prehospital system delay was 33.5minutes(interquartile range [IQR]=27.0, 42.0). Delay between call-received-by-ambulance and ambulance-dispatched was 2.48 minutes(IQR=1.47, 16.55); between ambulance-dispatch and arrival-at-patient-location was 8.07 minutes(IQR=1.30, 22.13); between arrival-at- and departurefrom-patient-location was 13.12 minutes(IQR=3.12, 32.2); and between leaving-patient-location to ED-registration was 9.90 minutes(IQR=1.62, 32.92). Comparing patients with prehospital system delay of less than 35.5 minutes versus more showed that the median delay between ambulancedispatch and arrival-at-patient-location was shorter(5.75 vs. 9.37 minutes, P0.01). The median delay between arrival-at-patient-location and leaving-patient-location was also shorter(10.78 vs.14.37 minutes, P0.01).CONCLUSION: Prehospital system delay in our patients was suboptimal. This is the first attempt at characterizing prehospital system delay in Singapore and forms the basis for improving efficiency of STEMI care.     

Electrocardiographic ST-segment elevation in the trauma patient: acute myocardial infarction vs myocardial contusion

The diagnosis of myocardial contusion in the setting of blunt trauma engenders much discussion and controversy-partly because of the lack of a gold standard for its identification other than histologic findings at autopsy. Furthermore, blunt cardiac trauma represents a spectrum of disorders ranging from transient electrocardiographic change to sudden death from myocardial rupture; hence, no single terminology exists to define such a wide range of scenarios. Here, we present 2 cases of electrocardiographic ST-segment elevation after high-speed motor vehicle crashes resulting in numerous injuries, including blunt chest trauma. Both patients demonstrated electrocardiographic ST-segment elevation, resulting from myocardial contusion and acute myocardial infarction.