Reperfusion therapy for STEMI: is there still a role for thrombolysis in the era of primary percutaneous coronary intervention?

Effect of different reperfusion strategies on recovery of ventricular function after ST-segment elevation myocardial infarction: A longitudinal single-center study

Background and Aims

Although the clinical benefit of percutaneous coronary intervention (PCI) on cardiovascular outcomes has been widely investigated, the impact of this revascularization strategy compared to other alternatives on the degree of left ventricular function recovery is poorly demonstrated. In this regard, we investigated whether time delays between the presentation of ST-segment elevation myocardial infarction (STEMI) and PCI in reperfusion strategies have different impacts on left ventricular function recovery.

Methods

In this single-center study, all the patients who presented with STEMI and a reduced left ventricular ejection fraction (LVEF ≤ 40%) were enrolled. Included patients were subjected to four different treatment groups of primary, rescue (immediate transfer for angioplasty due to failed fibrinolytic therapy), facilitated (fibrinolytic therapy followed by angioplasty within 24 h), and deferred (successful fibrinolytic therapy and PCI after 24 h) PCI based on hospital facilities. Echocardiography was performed for all the patients at the time of hospitalization and 6 months later.

Results

A total of 128 patients were included in this study. The LVEF improved by 15.3 ± 6.3%, 11.5 ± 3.61%, 4.0 ± 1.0%, and -1.3 ± 7.0% in primary, rescue, facilitated, and deferred PCI groups, respectively (p < 0.001). Patients undergoing deferred PCI experienced a significantly lower improvement in LVEF compared with primary and rescue PCI (p < 0.001).

Conclusion

Primary PCI demonstrated the most promising recovery in left ventricular function following STEMI compared to other alternative strategies. Performing PCI as soon as possible provides better recovery of LVEF.

Culprit Lesion Morphology of Rapidly Progressive and Extensive Anterior-Wall ST-Segment Elevation Myocardial Infarction

BACKGROUND

Rapidly progressive, extensive myocardial injury/infarction (RPEMI) beyond the concept of wave-front phenomenon can be observed even when achieving timely reperfusion; however, the pathogenesis of RPEMI remains unknown. This retrospective study investigated clinical and lesion characteristics of RPEMI, focusing on culprit-lesion morphology (CLM).

METHODS

Among patients with extensive anterior-wall ST-segment elevation myocardial infarction due to proximal left anterior descending artery lesions who had reperfusion within 3 hours of symptom onset, 60 patients undergoing both intravascular ultrasound and cardiac magnetic resonance imaging were enrolled. Myocardial injury/infarction before reperfusion therapy was assessed by QRS scores at hospitalization electrocardiogram, and the extent of myocardial injury/infarction was evaluated by cardiac magnetic resonance imaging, which measured area at risk, infarct size, myocardial salvage index, microvascular obstruction, and left ventricular ejection fraction. RPEMI was defined as lower left ventricular ejection fraction (less median value) with microvascular obstruction.

RESULTS

Despite comparable onset-to-door and onset-to-reperfusion times and area at risk, patients with RPEMI showed higher QRS scores at hospitalization (5 [4.3-6] versus 3 [2-4], P<0.001) and infarct size (26.5±9.1 versus 20.4±10.5%, P=0.04), and a tendency toward lower myocardial salvage index (0.27±0.14 versus 0.36±0.20, P=0.10) compared with those without. Patients with versus without RPEMI more frequently observed specific CLM on intravascular ultrasound, characterized by the combination of vulnerable plaques, plaque ruptures, and/or large thrombi. When stratified by CLM-score composed of these 3 criteria, higher CLM-scores were or tended to be associated with higher QRS scores and incidence of RPEMI. In multivariate analyses including no-reflow phenomenon and final coronary-flow deterioration, increased CLM-score (≥2) was independently associated with high QRS scores and RPEMI (odd ratio 11.25 [95% CI, 2.43-52.00]; P=0.002).

CONCLUSIONS

Vulnerable CLM was a consistent determinant of advanced myocardial injury/infarction both before and after reperfusion therapy and may play a pivotal role in the development of RPEMI.

Reconsidering treatment guidelines for acute myocardial infarction during the COVID-19 pandemic

Background

COVID-19 affects healthcare resource allocation, which could lead to treatment delay and poor outcomes in patients with acute myocardial infarction (AMI). We assessed the impact of the COVID-19 pandemic on AMI outcomes.

Methods

We compared outcomes of patients admitted for acute ST-elevation MI (STEMI) and non-STEMI (NSTEMI) during a non-COVID-19 pandemic period (January–February 2019; Group 1, n = 254) and a COVID-19 pandemic period (January–February 2020; Group 2, n = 124).

Results

For STEMI patients, the median of first medical contact (FMC) time, door-to-balloon time, and total myocardial ischemia time were significantly longer in Group 2 patients (all p < 0.05). Primary percutaneous intervention was performed significantly more often in Group 1 patients than in Group 2 patients, whereas thrombolytic therapy was used significantly more often in Group 2 patients than in Group 1 patients (all p < 0.05). However, the rates of and all-cause 30-day mortality and major adverse cardiac event (MACE) were not significantly different in the two periods (all p > 0.05). For NSTEMI patients, Group 2 patients had a higher rate of conservative therapy, a lower rate of reperfusion therapy, and longer FMC times (all p < 0.05). All-cause 30-day mortality and MACE were only higher in NSTEMI patients during the COVID-19 pandemic period (p < 0.001).

Conclusions

COVID-19 pandemic causes treatment delay in AMI patients and potentially leads to poor clinical outcome in NSTEMI patients. Thrombolytic therapy should be initiated without delay for STEMI when coronary intervention is not readily available; for NSTEMI patients, outcomes of invasive reperfusion were better than medical treatment.

Influence of Geographical Location on Access to Reperfusion Therapies and Mortality of Patients with STEMI in Sergipe: VICTIM Register

BACKGROUND

The concentration of high-complexity services in Aracaju, Sergipe can impose certain disparity in the quality of care for the patients with ST-segment elevation acute myocardial infarction (STEMI) (STEMI) who receive care from Brazil's Unified Health System (SUS, acronym in Portuguese) and whose symptoms started in other health regions of the state.

OBJECTIVE

To evaluate disparities in access to reperfusion therapies and 30-day mortality, among patients with STEMI, who were users of SUS, in each of the 7 health regions of Sergipe.

METHODS

A total of 844 patients with STEMI in the period from 2014 to 2018, assisted by the only hospital with the capacity to offer primary percutaneous coronary intervention (PPCI) to SUS users in the state of Sergipe, were evaluated. The patients were divided into 7 groups according to the location at the onset of symptoms, following the existing division of health regions in the state. For comparison between groups, a significant difference was considered when p < 0.05.

RESULTS

Of the total of 844 patients suffering from STEMI who were transferred to the hospital with PPCI that serves SUS patients, 386 patients (45.8%) underwent primary angioplasty. The mean rate of fibrinolytic use was 2.6%, with no differences between the regions. The mean total time of arrival to the hospital with PPCI was 21 hours and 55 minutes, with a median of 10 hours and 22 minutes (6 hours and 30 minutes to 22 hours and 52 minutes). Total 30-day mortality was 12.8%, but without differences between the regions, even when adjusted for age and sex.

CONCLUSIONS

This study reveals that fibrinolytics are underused throughout the state and that there is a significant delay in access to the hospital with PPCI, in all health regions of Sergipe.

COVID-19 pandemic and coronary angiography for ST-elevation myocardial infarction, use of mechanical support and mechanical complications in Canada; a Canadian Association of Interventional Cardiology national survey

Background

As a result of the COVID-19 pandemic first wave, reductions in ST-elevation myocardial infarction (STEMI) invasive care, ranging from 23% to 76%, have been reported from various countries. Whether this change had any impact on coronary angiography (CA) volume or on mechanical support device use for STEMI and post-STEMI mechanical complications in Canada is unknown.

Methods

We administered a Canada-wide survey to all cardiac catheterization laboratory directors, seeking the volume of CA use for STEMI performed during the period from March 1 2020 to May 31, 2020 (pandemic period), and during 2 control periods (March 1, 2019 to May 31, 2019 and March 1, 2018 to May 31, 2018). The number of left ventricular support devices used, as well as the number of ventricular septal defects and papillary muscle rupture cases diagnosed, was also recorded. We also assessed whether the number of COVID-19 cases recorded in each province was associated with STEMI-related CA volume.

Results

A total of 41 of 42 Canadian catheterization laboratories (98%) provided data. There was a modest but statistically significant 16% reduction (incidence rate ratio [IRR] 0.84; 95% confidence interval 0.80-0.87) in CA for STEMI during the first wave of the pandemic, compared to control periods. IRR was not associated with provincial COVID-19 caseload. We observed a 26% reduction (IRR 0.74; 95% confidence interval 0.61-0.89) in the use of intra-aortic balloon pump use for STEMI. Use of an Impella pump and mechanical complications from STEMI were exceedingly rare.

Conclusions

We observed a modest 16% decrease in use of CA for STEMI during the pandemic first wave in Canada, lower than the level reported in other countries. Provincial COVID-19 caseload did not influence this reduction.

MiR-223-3p in Cardiovascular Diseases: A Biomarker and Potential Therapeutic Target

Cardiovascular diseases, involving vasculopathy, cardiac dysfunction, or circulatory disturbance, have become the major cause of death globally and brought heavy social burdens. The complexity and diversity of the pathogenic factors add difficulties to diagnosis and treatment, as well as lead to poor prognosis of these diseases. MicroRNAs are short non-coding RNAs to modulate gene expression through directly binding to the 3′-untranslated regions of mRNAs of target genes and thereby to downregulate the protein levels post-transcriptionally. The multiple regulatory effects of microRNAs have been investigated extensively in cardiovascular diseases. MiR-223-3p, expressed in multiple cells such as macrophages, platelets, hepatocytes, and cardiomyocytes to modulate their cellular activities through targeting a variety of genes, is involved in the pathological progression of many cardiovascular diseases. It participates in regulation of several crucial signaling pathways such as phosphatidylinositol 3-kinase/protein kinase B, insulin-like growth factor 1, nuclear factor kappa B, mitogen-activated protein kinase, NOD-like receptor family pyrin domain containing 3 inflammasome, and ribosomal protein S6 kinase B1/hypoxia inducible factor 1 α pathways to affect cell proliferation, migration, apoptosis, hypertrophy, and polarization, as well as electrophysiology, resulting in dysfunction of cardiovascular system. Here, in this review, we will discuss the role of miR-223-3p in cardiovascular diseases, involving its verified targets, influenced signaling pathways, and regulation of cell function. In addition, the potential of miR-223-3p as therapeutic target and biomarker for diagnosis and prediction of cardiovascular diseases will be further discussed, providing clues for clinicians.

Neutrophils promote venular thrombosis by shaping the rheological environment for platelet aggregation

In advanced inflammatory disease, microvascular thrombosis leads to the interruption of blood supply and provokes ischemic tissue injury. Recently, intravascularly adherent leukocytes have been reported to shape the blood flow in their immediate vascular environment. Whether these rheological effects are relevant for microvascular thrombogenesis remains elusive. Employing multi-channel in vivo microscopy, analyses in microfluidic devices, and computational modeling, we identified a previously unanticipated role of leukocytes for microvascular clot formation in inflamed tissue. For this purpose, neutrophils adhere at distinct sites in the microvasculature where these immune cells effectively promote thrombosis by shaping the rheological environment for platelet aggregation. In contrast to larger (lower-shear) vessels, this process in high-shear microvessels does not require fibrin generation or extracellular trap formation, but involves GPIbα-vWF and CD40-CD40L-dependent platelet interactions. Conversely, interference with these cellular interactions substantially compromises microvascular clotting. Thus, leukocytes shape the rheological environment in the inflamed venular microvasculature for platelet aggregation thereby effectively promoting the formation of blood clots. Targeting this specific crosstalk between the immune system and the hemostatic system might be instrumental for the prevention and treatment of microvascular thromboembolic pathologies, which are inaccessible to invasive revascularization strategies.

Five-year outcomes following timely primary percutaneous intervention, late primary percutaneous intervention, or a pharmaco-invasive strategy in ST-segment elevation myocardial infarction: the FAST-MI programme

Aims

ST-segment elevation myocardial infarction (STEMI) guidelines recommend primary percutaneous coronary intervention (pPCI) as the default reperfusion strategy when feasible ≤120 min of diagnostic ECG, and a pharmaco-invasive strategy otherwise. There is, however, a lack of direct evidence to support the guidelines, and in real-world situations, pPCI is often performed beyond recommended timelines. To assess 5-year outcomes according to timing of pPCI (timely vs. late) compared with a pharmaco-invasive strategy (fibrinolysis with referral to PCI centre).

Methods and results

The French registry of Acute ST-elevation and non-ST-elevation Myocardial Infarction (FAST-MI) programme consists of nationwide observational surveys consecutively recruiting patients admitted for acute myocardial infarction every 5 years. Among the 4250 STEMI patients in the 2005 and 2010 cohorts, those with reperfusion therapy and onset-to-first call time &lt;12 h (n = 2942) were included. Outcomes at 5 years were compared according to type of reperfusion strategy and timing of pPCI, using Cox multivariable analyses and propensity score matching. Among those, 1288 (54%) patients had timely pPCI (≤120 min from ECG), 830 (28%) late pPCI (&gt;120 min), and 824 (28%) intravenous fibrinolysis. Five-year survival was higher with a pharmaco-invasive strategy (89.8%) compared with late pPCI [79.5%; adjusted hazard ratio (HR) 1.51; 1.13–2.02] and similar to timely pPCI (88.2%, adjusted HR 1.02; 0.75–1.38). Concordant results were observed in propensity score-matched cohorts and for event-free survival.

Conclusion

A substantial proportion of patients have pPCI beyond recommended timelines. As foreseen by the guidelines, these patients have poorer 5-year outcomes, compared with a pharmaco-invasive strategy.

Cardiac Muscle Membrane Stabilization in Myocardial Reperfusion Injury

The phospholipid bilayer membrane that surrounds each cell in the body represents the first and last line of defense for preserving overall cell viability. In several forms of cardiac and skeletal muscle disease, deficits in the integrity of the muscle membrane play a central role in disease pathogenesis. In Duchenne muscular dystrophy, an inherited and uniformly fatal disease of progressive muscle deterioration, muscle membrane instability is the primary cause of disease, including significant heart disease, for which there is no cure or highly effective treatment. Further, in multiple clinical forms of myocardial ischemia-reperfusion injury, the cardiac sarcolemma is damaged and this plays a key role in disease etiology. In this review, cardiac muscle membrane stability is addressed, with a focus on synthetic block copolymers as a unique chemical-based approach to stabilize damaged muscle membranes. Recent advances using clinically relevant small and large animal models of heart disease are discussed. In addition, mechanistic insights into the copolymer-muscle membrane interface, featuring atomistic, molecular, and physiological structure-function approaches are highlighted. Collectively, muscle membrane instability contributes significantly to morbidity and mortality in prominent acquired and inherited heart diseases. In this context, chemical-based muscle membrane stabilizers provide a novel therapeutic approach for a myriad of heart diseases wherein the integrity of the cardiac muscle membrane is at risk.

Clinical associations of microvascular obstruction and intramyocardial hemorrhage on cardiovascular magnetic resonance in patients with acute ST segment elevation myocardial infarction (STEMI): An observational cohort study

Acute myocardial infarction (AMI) is recognized as being a life-threatening event. Both microvascular obstruction (MVO) and intramyocardial hemorrhage (IMH) have been recognized as poor prognostic factors in myocardial infarct (MI) since they adversely affect left ventricular remodeling. MVO refers to small vessels changes that prevent adequate tissue perfusion despite revascularization whereas IMH is a severe form of MVO. A limited number of studies have demonstrated the segmental intervention time and the clinical factors in the presence of MVO and IMH. Therefore, we aimed in this study to determine the correlations of the intervention-associated and clinical indexes with malignant cardiovascular magnetic resonance (CMR) signs in patients with AMI.Sixty-three patients with STEMI who underwent primary percutaneous coronary intervention (PPCI) within 12 hours were included in this study. A 3.0-T CMR scan was prescribed, and the subsequent image analysis was conducted by researchers blinded to the clinical index results. Late-gadolinium enhancement (LGE) and T2* sequences were mainly used for MVO and IMH identification and quantification.Patients exhibiting both MVO and IMH had the highest level of LGE (P < .001) and were significantly more frequently assigned to a pre-PPCI thrombolysis in myocardial infarction (TIMI) flow class of 0 (n=25, 89.3%). The MVO size correlated positively with the IMH size (r = 0.81, P < .01). A pre-PPCI TIMI flow class of 0 was found to reliably predict the presence of IMH (P < .001). Patients who received the intervention 4 to 6 hours after MI onset were more likely to exhibit MVO and IMH, although this trend was not statistically significant.We showed in our study that both MVO and IMH correlated with the degree of AMI and the pre-PPCI coronary flow, and both tended to occur more frequently in cases involving an interval of 4 to 6 hours between the onset of MI and the intervention. CMR is a reliable method for assessing MVO and IMH and its imaging features following gadolinium administration are characteristic. These findings stress the importance of using CMR in evaluating and improving the outcome of the medical management.

GYY4137 protects against myocardial ischemia/reperfusion injury via activation of the PHLPP-1/Akt/Nrf2 signaling pathway in diabetic mice

BACKGROUND

This study explores the protective effects of a hydrogen sulfide donor, morpholin-4-ium 4-methoxyphenyl-morpholino-phosphinodithioate (GYY4137), in the hearts of diabetic mice that had been subjected to myocardial ischemia/reperfusion injury. Diabetes impairs the Akt pathway, in which the Akt protein is dephosphorylated and inactivated by PH domain leucine-rich repeat protein phosphatase-1 (PHLPP-1). However, the function of PHLPP-1 and molecular mechanism that underlies the cardiac protection exerted by GYY4137 remains unknown.

METHODS

Diabetic or nondiabetic mice were subjected to 45 min of coronary artery occlusion followed by 2 h of reperfusion. H9c2 cells were cultured with normal or high glucose and then subjected to 3 h of hypoxia followed by 6 h of reoxygenation. Pretreatment with GYY4137 was performed in a randomized manner before ischemia/reperfusion or hypoxia/reoxygenation. The infarct size, cardiomyocyte apoptosis, and oxidative stress were measured. Western blotting was conducted to elucidate the protective mechanism.

RESULTS

Diabetic mice or H9c2 cells exposed to high glucose displayed a larger infarct size, more severe cardiomyocyte apoptosis, lower cell viability, and increased oxidative stress, which were associated with increased levels of PHLPP-1 and reduced levels of p-Akt and nuclear factor-erythroid-2-related factor 2 (Nrf2) protein expression. These changes were prevented/reversed by GYYG4137 pretreatment. At the cellular level, PHLPP-1 siRNA attenuated cellular injury, and this was associated with increased p-Akt and nuclear Nrf2 protein, whereas the decrement of Akt phosphorylation induced by LY294002 augmented cellular injury and decreased nuclear Nrf2.

CONCLUSIONS

GYY4137 activates the PHLPP-1/Akt/Nrf2 pathway to protect against diabetic myocardial ischemia/reperfusion injury.

Occurrence and Impact of Time Delay to Primary Percutaneous Coronary Intervention in Patients With ST-Segment Elevation Myocardial Infarction

Background

The aim of the study was to evaluate the occurrence, duration and impact of time delays to primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI).

Methods

A total of 357 consecutive STEMI patients enrolled in the prospective Special Program University Medicine ACS (SPUM-ACS) cohort were included. In order to identify the causes behind a possible treatment delay, we constructed four different time points which included: 1) symptom onset to hospital arrival, 2) hospital arrival to arrival in the catheterization laboratory, 3) hospital arrival to first balloon inflation, and 4) time from arrival in the catheterization laboratory to first balloon inflation in addition to total ischemic time. Patients were stratified according to a delay > 3 h, > 30 min, > 90 min and > 1 h, respectively and major adverse events at 0, 30 and 365 days were analyzed.

Results

Resuscitated STEMI patients (23 patients) and STEMI patients presenting at weekends (101 patients) and to lesser extent at night hours (100 patients) experienced more time delays than stable patients and those presenting at office hours. Median door-to-balloon time averaged 93 min in resuscitated, but 65 min in stable patients. Median door-to-balloon time at weekends and public holidays was 89 min, but 68 min at office hours. Median time from hospital arrival to cathlab arrival at weekends and public holidays was 30 min, but 15 min during office hours. Corresponding times for resuscitated patients was 45 and 15 min in stable patients. Of note, resuscitated patients were late presenters as regards time from symptoms onset to hospital arrival with a median time of 180 min compared to 155 min in stable patients. Median total ischemic time was 225 min for all patients, 223 min at day hours, 239 at night hours, 244 min at weekends, 233 min at office days, 220 min in stable patients and 273 min in resuscitated patients. Patients with STEMI who arrived > 3 h after symptom onset had a higher rate of myocardial infarction (MI) at 1 year (1.6% vs. 9% in < 3 h; P = 0.008). Furthermore, STEMI patients who had a delay of > 1 h from cathlab arrival to first balloon inflation had a higher rate of in hospital reinfarction at 0 day (0.6% vs. 0% in < 1 h; P = 0.007), MI at 30 days (0.8% vs. 0% in < 1 h; P = 0.001) and MI at 1 year (1.4% vs. 1.1% in < 1 h; P = 0.012). Similarly, in these patients, cardiac deaths at 0 day (0.8% vs. 0.6% in < 1 h; P = 0.035) and at 30 days (0.8% vs. 0.6% in < 1 h; P = 0.035) were higher as were major adverse cardiovascular events (MACCE) at 0 day (1.4% vs. 0.8% in < 1 h; P = 0.004).

Conclusion

Resuscitated STEMI patients and those presenting at weekends and to lesser extent at night hours experienced more time delays and longer ischemic time than stable patients and those presenting at office hours. In STEMI patients, any delay in treatment increased their risk of MACCE. Efforts should focus on improving patient’s awareness along with minimizing in-hospital transfer to the catheterization laboratory especially at weekends and in resuscitated patients.

Efficacy and Safety of a Pharmaco-Invasive Strategy With Half-Dose Alteplase Versus Primary Angioplasty in ST-Segment-Elevation Myocardial Infarction: EARLY-MYO Trial (Early Routine Catheterization After Alteplase Fibrinolysis Versus Primary PCI in Acute ST-Segment-Elevation Myocardial Infarction)

BACKGROUND

Timely primary percutaneous coronary intervention (PPCI) cannot be offered to all patients with ST-segment-elevation myocardial infarction (STEMI). Pharmaco-invasive (PhI) strategy has been proposed as a valuable alternative for eligible patients with STEMI. We conducted a randomized study to compare the efficacy and safety of a PhI strategy with half-dose fibrinolytic regimen versus PPCI in patients with STEMI.

METHODS

The EARLY-MYO trial (Early Routine Catheterization After Alteplase Fibrinolysis Versus Primary PCI in Acute ST-Segment-Elevation Myocardial Infarction) was an investigator-initiated, prospective, multicenter, randomized, noninferiority trial comparing a PhI strategy with half-dose alteplase versus PPCI in patients with STEMI 18 to 75 years of age presenting ≤6 hours after symptom onset but with an expected PCI-related delay. The primary end point of the study was complete epicardial and myocardial reperfusion after PCI, defined as thrombolysis in myocardial infarction flow grade 3, thrombolysis in myocardial infarction myocardial perfusion grade 3, and ST-segment resolution ≥70%. We also measured infarct size and left ventricular ejection fraction with cardiac magnetic resonance and recorded 30-day clinical and safety outcomes.

RESULTS

A total of 344 patients from 7 centers were randomized to PhI (n=171) or PPCI (n=173). PhI was noninferior (and even superior) to PPCI for the primary end point (34.2% versus 22.8%, P_{noninferiority}<0.05, P_superiority=0.022), with no significant differences in the frequency of the individual components of the combined end point: thrombolysis in myocardial infarction flow 3 (91.3% versus 89.2%, P=0.580), thrombolysis in myocardial infarction myocardial perfusion grade 3 (65.8% versus 62.9%, P=0.730), and ST-segment resolution ≥70% (50.9% versus 45.5%, P=0.377). Infarct size (23.3%±11.3% versus 25.8%±13.7%, P=0.101) and left ventricular ejection fraction (52.2%±11.0% versus 51.4%±12.0%, P=0.562) were similar in both groups. No significant differences occurred in 30-day rates of total death (0.6% versus 1.2%, P=1.0), reinfarction (0.6% versus 0.6%, P=1.0), heart failure (13.5% versus 16.2%, P=0.545), major bleeding events (0.6% versus 0%, P=0.497), or intracranial hemorrhage (0% versus 0%), but minor bleeding (26.9% versus 11.0%, P<0.001) was observed more often in the PhI group.

CONCLUSIONS

For patients with STEMI presenting ≤6 hours after symptom onset and with an expected PCI-related delay, a PhI strategy with half-dose alteplase and timely PCI offers more complete epicardial and myocardial reperfusion when compared with PPCI. Adequately powered trials with this reperfusion strategy to assess clinical and safety outcomes are warranted.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01930682.

Comparative efficacy and safety of reperfusion therapy with fibrinolytic agents in patients with ST-segment elevation myocardial infarction: a systematic review and network meta-analysis

BACKGROUND

Fibrinolytic therapy offers an alternative to mechanical reperfusion for ST-segment elevation myocardial infarction (STEMI) in settings where health-care resources are scarce. Comprehensive evidence comparing different agents is still unavailable. In this study, we examined the effects of various fibrinolytic drugs on clinical outcomes.

METHODS

We did a network meta-analysis based on a systematic review of randomised controlled trials comparing fibrinolytic drugs in patients with STEMI. Several databases were searched from inception up to Feb 28, 2017. We included only randomised controlled trials that compared fibrinolytic agents as a reperfusion therapy in adult patients with STEMI, whether given alone or in combination with adjunctive antithrombotic therapy, against other fibrinolytic agents, a placebo, or no treatment. Only trials investigating agents with an approved indication of reperfusion therapy in STEMI (streptokinase, tenecteplase, alteplase, and reteplase) were included. The primary efficacy outcome was all-cause mortality within 30-35 days and the primary safety outcome was major bleeding. This study is registered with PROSPERO (CRD42016042131).

FINDINGS

A total of 40 eligible studies involving 128 071 patients treated with 12 different fibrinolytic regimens were assessed. Compared with accelerated infusion of alteplase with parenteral anticoagulants as background therapy, streptokinase and non-accelerated infusion of alteplase were significantly associated with an increased risk of all-cause mortality (risk ratio [RR] 1·14 [95% CI 1·05-1·24] for streptokinase plus parenteral anticoagulants; RR 1·26 [1·10-1·45] for non-accelerated alteplase plus parenteral anticoagulants). No significant difference in mortality risk was recorded between accelerated infusion of alteplase, tenecteplase, and reteplase with parenteral anticoagulants as background therapy. For major bleeding, a tenecteplase-based regimen tended to be associated with lower risk of bleeding compared with other regimens (RR 0·79 [95% CI 0·63-1·00]). The addition of glycoprotein IIb or IIIa inhibitors to fibrinolytic therapy increased the risk of major bleeding by 1·27-8·82-times compared with accelerated infusion alteplase plus parenteral anticoagulants (RR 1·47 [95% CI 1·10-1·98] for tenecteplase plus parenteral anticoagulants plus glycoprotein inhibitors; RR 1·88 [1·24-2·86] for reteplase plus parenteral anticoagulants plus glycoprotein inhibitors).

INTERPRETATION

Significant differences exist among various fibrinolytic regimens as reperfusion therapy in STEMI and alteplase (accelerated infusion), tenecteplase, and reteplase should be considered over streptokinase and non-accelerated infusion of alteplase. The addition of glycoprotein IIb or IIIa inhibitors to fibrinolytic therapy should be discouraged.

FUNDING

None.

Unmet goals in the treatment of Acute Myocardial Infarction: Review

Reperfusion therapy decreases myocardium damage during an acute coronary event and consequently mortality. However, there are unmet needs in the treatment of acute myocardial infarction, consequently mortality and heart failure continue to occur in about 10% and 20% of cases, respectively. Different strategies could improve reperfusion. These strategies, like generation of warning sign recognition and being initially assisted and transferred by an emergency service, could reduce the time to reperfusion. If the first electrocardiogram is performed en route, it can be transmitted and interpreted in a timely manner by a specialist at the receiving center, bypassing community hospitals without percutaneous coronary intervention capabilities. To administer thrombolytic therapy during transport to the catheterization laboratory could reduce time to reperfusion in cases with expected prolonged transport time to a percutaneous coronary intervention center or to a center without primary percutaneous coronary intervention capabilities with additional expected delay, known as pharmaco-invasive strategy. Myocardial reperfusion is known to produce damage and cell death, which defines the reperfusion injury. Lack of resolution of ST segment is used as a marker of reperfusion failure. In patients without ST segment resolution, mortality triples. It is important to note that, until recently, reperfusion injury and no-reflow were interpreted as a single entity and we should differentiate them as different entities; whereas no-reflow is the failure to obtain tissue flow, reperfusion injury is actually the damage produced by achieving flow. Therefore, treatment of no-reflow is obtained by tissue flow, whereas in reperfusion injury the treatment objective is protection of susceptible myocardium from reperfusion injury. Numerous trials for the treatment of reperfusion injury have been unsuccessful. Newer hypotheses such as “ controlled reperfusion”, in which the interventional cardiologist assumes not only the treatment of the culprit vessel but also the way to reperfuse the myocardium at risk, could reduce reperfusion injury.

Global geographical variations in ST-segment elevation myocardial infarction management and post-discharge mortality

BACKGROUND

There is a shortage of information on regional variations in ST-segment elevation myocardial infarction (STEMI) management and prognosis at a global level. We aimed to compare patient profiles, in-hospital management and post-discharge mortality across several world regions.

METHODS

In total, 11,559 patients with STEMI were enrolled in two prospective studies of acute coronary syndrome survivors: EPICOR (4943 patients from 555 hospitals in 20 countries in Europe and Latin America recruited between September 2010 and March 2011) and EPICOR Asia (6616 patients from 218 hospitals in eight Asian countries recruited between June 2011 and May 2012). Comparisons were performed by eight pre-defined regions: Northern Europe (NE), Southern Europe (SE), Eastern Europe (EE), Latin America (LA), China (CN), India (IN), Southeast Asia (SA), and South Korea/Hong Kong/Singapore (KS).

RESULTS

Reperfusion therapy rates ranged between 53.9% (IN) and 81.2% (SE), primary percutaneous coronary intervention (PCI) between 24.8% (IN) and 65.6% (NE) and fibrinolysis between 8.1% (CN) and 34.2% (SA). Median time to primary PCI (h) ranged from 3.9 (NE) to 20.9 (IN) and to fibrinolysis from 2.4 (SE) to 6.3 (IN). Two-year mortality ranged between 2.5% in NE and 7.4% in LA. Regional variations in mortality persisted after adjustment for reperfusion therapy and known prognostic factors.

CONCLUSIONS

Among patients with STEMI, there is a wide regional variation in clinical profiles, hospital care and mortality. Substantial room for improvement remains at a global level for increasing reperfusion rates, reducing delays and post-discharge mortality in patients with STEMI.

Effect of supplementation of lecithin and carnitine on growth performance and nutrient digestibility in pigs fed high-fat diet

Aim:

To study the effect of dietary supplementation of lecithin and carnitine on growth performance and nutrient digestibility in pigs fed high-fat diet.

Materials and Methods:

A total of 30 weaned female large white Yorkshire piglets of 2 months of age were selected and randomly divided into three groups allotted to three dietary treatments, T1 - Control ration as per the National Research Council nutrient requirement, T2 - Control ration plus 5% fat, and T3 - T2 plus 0.5% lecithin plus 150 mg/kg carnitine. The total dry matter (DM) intake, fortnightly body weight of each individual animal was recorded. Digestibility trial was conducted toward the end of the experiment to determine the digestibility coefficient of various nutrients.

Results:

There was a significant improvement (p<0.01) observed for pigs under supplementary groups T2 and T3 than that of control group (T1) with regards to growth parameters studied such as total DM intake, average final body weight and total weight gain whereas among supplementary groups, pigs reared on T3 group had better intake (p<0.01) when compared to T2 group. Statistical analysis of data revealed that no differences were observed (p>0.05) among the three treatments on average daily gain, feed conversion efficiency, and nutrient digestibility during the overall period.

Conclusion:

It was concluded that the dietary inclusion of animal fat at 5% level or animal fat along with lecithin (0.5%) and carnitine (150 mg/kg) improved the growth performance in pigs than non-supplemented group and from the economic point of view, dietary incorporation of animal fat at 5% would be beneficial for improving growth in pigs without dietary modifiers.

MicroRNA-223-5p and -3p Cooperatively Suppress Necroptosis in Ischemic/Reperfused Hearts

Recent studies have shown that myocardial ischemia/reperfusion (I/R)-induced necrosis can be controlled by multiple genes. In this study, we observed that both strands (5p and 3p) of miR-223 were remarkably dysregulated in mouse hearts upon I/R. Precursor miR-223 (pre-miR-223) transgenic mouse hearts exhibited better recovery of contractile performance over reperfusion period and lesser degree of myocardial necrosis than wild type hearts upon ex vivo and in vivo myocardial ischemia. Conversely, pre-miR-223 knock-out (KO) mouse hearts displayed opposite effects. Furthermore, we found that the RIP1/RIP3/MLKL necroptotic pathway and inflammatory response were suppressed in transgenic hearts, whereas they were activated in pre-miR-223 KO hearts upon I/R compared with wild type controls. Accordingly, treatment of pre-miR-223 KO mice with necrostatin-1s, a potent necroptosis inhibitor, significantly decreased I/R-triggered cardiac necroptosis, infarction size, and dysfunction. Mechanistically, we identified two critical cell death receptors, TNFR1 and DR6, as direct targets of miR-223-5p, whereas miR-223-3p directly suppressed the expression of NLRP3 and IκB kinase α, two important mediators known to be involved in I/R-induced inflammation and cell necroptosis. Our findings indicate that miR-223-5p/-3p duplex works together and cooperatively inhibits I/R-induced cardiac necroptosis at multiple layers. Thus, pre-miR-223 may constitute a new therapeutic agent for the treatment of ischemic heart disease.

Decade-long trends in the timeliness of receipt of a primary percutaneous coronary intervention

Objectives

The purpose of this study was to examine decade-long trends (2001–2011) in, and factors associated with, door-to-balloon time within 90 minutes of hospital presentation among patients hospitalized with ST-segment elevation myocardial infarction (STEMI) who received a primary percutaneous coronary intervention (PCI).

Methods

Residents of central Massachusetts hospitalized with STEMI who received a primary PCI at two major PCI-capable medical centers in central Massachusetts on a biennial basis between 2001 and 2011 comprised the study population (n=629). Multivariable regression analyses were used to examine factors associated with failing to receive a primary PCI within 90 minutes after emergency department (ED) arrival.

Results

The average age of this patient population was 61.9 years; 30.5% were women, and 91.7% were White. During the years under study, 50.9% of patients received a primary PCI within 90 minutes of ED arrival; this proportion increased from 2001/2003 (17.2%) to 2009/2011 (70.5%) (P<0.001). Having previously undergone coronary artery bypass graft surgery, arriving at the ED by car/walk-in and during off-hours were significantly associated with a higher risk of failing to receive a primary PCI within 90 minutes of ED arrival.

Conclusion

The likelihood of receiving a timely primary PCI in residents of central Massachusetts hospitalized with STEMI at the major teaching/community medical centers increased dramatically during the years under study. Several groups were identified for purposes of heightened surveillance and intervention efforts to reduce the likelihood of failing to receive a timely primary PCI among patients acutely diagnosed with STEMI.

Defining a COPD composite safety endpoint for demonstrating efficacy in clinical trials: results from the randomized, placebo-controlled UPLIFT® trial

Background

Chronic obstructive pulmonary disease (COPD) clinical trials evaluating hard endpoints (mortality, hospitalized exacerbations) require a large number of subjects and prolonged observational periods. We hypothesized that a composite endpoint of respiratory outcomes (CERO) can help evaluate safety and benefit in COPD trials.

Methods

Retrospective analysis of 5992 patients enrolled in the 4-year UPLIFT® trial, a randomized trial of tiotropium versus placebo in patients with moderate-to-severe COPD. Patients were permitted to continue using their usual COPD medications except for other anticholinergics. The CERO included deaths, respiratory failure, hospitalized exacerbations, and trial dropout due to COPD worsening. The incidence rates (IRs) per 100 patient-years and risk ratios (RRs and 95 % CI) were determined at years 1 to 4. The effect of treatments on CERO was similarly assessed. A power analysis helped calculate the sample size needed to achieve outcome differences between treatments.

Results

The CERO IRs at years 1 to 4 for tiotropium versus placebo were 16, 13, 11, and 11, and 21, 16, 14, and 13, respectively. The RRs of CERO between tiotropium and placebo at the same time points were: RR-year 0.76 (0.67, 0.86), 0.80 (0.72, 0.88), 0.81 (0.74, 0.89), and 0.84 (0.77, 0.92). Using the IRs and RRs, the sample size (alpha = 0.05 two-sided, 90 % power) for studies of 1, 2, 3, and 4 years would be 1546, 1392, 1216, and 1504 per treatment group, respectively, with 575, 810, 930, 1383 required events, respectively, for hypothetical, event-driven studies.

Conclusions

A composite endpoint incorporating relatively infrequent serious or significant COPD-related safety outcomes could be useful in clinical trials. In UPLIFT®, CERO events were significantly reduced in patients receiving tiotropium compared with placebo.

Trial registration

NCT00144339.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-016-0361-4) contains supplementary material, which is available to authorized users.

Fibrinolytic therapy in hospitals without percutaneous coronary intervention capabilities in China from 2001 to 2011: China PEACE-retrospective AMI study

BACKGROUND

Fibrinolytic therapy is the primary reperfusion strategy for ST-segment elevation myocardial infarction in China, and yet little is known about the quality of care regarding its use and whether it has changed over time. This issue is particularly important in hospitals without the capacity for cardiovascular intervention.

METHODS

Using a sequential cross-sectional study with two-stage random sampling in 2001, 2006, and 2011, we characterised the use, timing, type and dose of fibrinolytic therapy in a nationally representative sample of patients with ST-segment elevation myocardial infarction admitted to hospitals without the ability to perform percutaneous coronary intervention.

RESULTS

We identified 5306 patients; 2812 (53.0%) were admitted within 12 hours of symptom onset, of whom 2463 (87.6%) were ideal candidates for fibrinolytic therapy. The weighted proportion of ideal candidates receiving fibrinolytic therapy was 45.8% in 2001, 50.0% in 2006, and 53.0% in 2011 ( P_trend=0.0042). There were no regional differences in fibrinolytic therapy use. Almost all ideal patients (95.1%) were treated after admission to the hospital rather than in the emergency department. Median admission to needle time was 35 minutes (interquartile range 10-82) in 2011, which did not improve from 2006. Underdosing was common. Urokinase, with little evidence of efficacy, was used in 90.2% of patients.

CONCLUSIONS

Over the past decade in China, the potential benefits of fibrinolytic therapy were compromised by underuse, patient and hospital delays, underdosing and the predominant use of urokinase, an agent for which there is little clinical evidence. There are ample opportunities for improvement.

Socio-economic Inequality in the Use of Procedures and Mortality Among AMI Patients: Quantifying the Effects Along Different Paths

It is not known whether inequality in access to cardiac procedures translates into inequality in mortality. In this paper, we use a path analysis model to quantify both the direct effect of socio-economic status on mortality and the indirect effect of socio-economic status on mortality as mediated by the provision of cardiac procedures. The study links microdata from the Finnish and Norwegian national patient registers describing treatment episodes with data from prescription registers, causes-of-death registers and registers covering education and income. We show that socio-economic variables affect access to percutaneous coronary intervention in both countries, but that these effects are only moderate and that the indirect effects of the socio-economic factors on mortality through access to percutaneous coronary intervention are minor. The direct effects of income and education on mortality are significantly larger. We conclude that the socio-economic gradient in the use of percutaneous coronary intervention adds to socio-economic differences in mortality to little or no extent.

Moutan cortex extract exerts protective effects in a rat model of cardiac ischemia/reperfusion

Moutan cortex (MC) is a traditional Chinese medicine with diverse biological effects. The present study was performed to investigate the effects of MC on myocardial ischemia/reperfusion (I/R) in rats and to explore its possible mechanisms. Sprague-Dawley rats were administered MC extract (1.98 g/kg, i.g.) for 14 days and underwent a subsequent open-chest procedure involving 30 min of myocardial ischemia and 60 min of reperfusion. The cardioprotective effect of MC was demonstrated by reduced infarct size and marked improvement in the histopathological examination. The increase in the activity of superoxide dismutase (SOD) and glutathione (GSH) as well as the reduction of malondialdehyde (MDA) indicated that MC effectively promoted the anti-oxidative defense system. Increased anti-oxidative defense was accompanied by decreased release of lactate dehydrogenase (LDH) and creatine kinase (CK). The reduction in TUNEL-positive myocytes demonstrated that MC decreased myocardial apoptosis. The mRNA expression of B cell leukemia-2 (Bcl-2) was upregulated by MC and the ratio of Bcl-2/Bcl-2-associated X protein (Bax) mRNA expression was increased. MC pretreatment decreased the mRNA expression of inducible nitric oxide synthase (iNOS). The data from this study suggest that MC exerted protective effects on acute myocardial I/R injury via anti-oxidative and anti-apoptotic activities.

First medical contact in patients with STEMI and its impact on time to diagnosis; an explorative cross-sectional study

OBJECTIVE

It is unknown into what extent patients with ST-elevation myocardial infarction (STEMI) utilise a joint service number (Swedish Healthcare Direct, SHD) as first medical contact (FMC) instead of Emergency Medical Services (EMS) and how this impact time to diagnosis. We aimed to (1) describe patients' FMC; (2) find explanatory factors influencing their FMC (ie, EMS and SHD) and (3) explore the time interval from symptom onset to diagnosis.

SETTING

Multicentred study, Sweden.

METHODS

Cross-sectional, enrolling patients with consecutive STEMI admitted within 24 h from admission.

RESULTS

We included 109 women and 336 men (mean age 66±11 years). Although 83% arrived by ambulance to the hospital, just half of the patients (51%) called EMS as their FMC. Other utilised SHD (21%), contacted their primary healthcare centre (14%), or went directly to the emergency room (14%). Reasons for not contacting EMS were predominantly; (1) my transport mode was faster (40%), (2) did not consider myself sick enough (30%), and (3) it was easier to be driven or taking a taxi (25%). Predictors associated with contacting SHD as FMC were female gender (OR 1.92), higher education (OR 2.40), history of diabetes (OR 2.10), pain in throat/neck (OR 2.24) and pain intensity (OR 0.85). Predictors associated with contacting EMS as FMC were history of MI (OR 2.18), atrial fibrillation (OR 3.81), abdominal pain (OR 0.35) and believing the symptoms originating from the heart (OR 1.60). Symptom onset to diagnosis time was significantly longer when turning to the SHD instead of the EMS as FMC (1:59 vs 1:21 h, p<0.001).

CONCLUSIONS

Using other forms of contacts than EMS, significantly prolong delay times, and could adversely affect patient prognosis. Nevertheless, having the opportunity to call the SHD might also, in some instances, lower the threshold for taking contact with the healthcare system, and thus lowers the number that would otherwise have delayed even longer.

Gender-related mortality and in-hospital complications following ST-segment elevation myocardial infarction: data from a primary percutaneous coronary intervention cohort

BACKGROUND

The increased mortality related to female gender in ST-segment elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention (PPCI) has been reported from various patient cohorts and treatment strategies with controversial results. In the present work, we evaluated the impact of female gender on mortality and in-hospital complications among a specific subset of consecutive STEMI patients managed solely by PPCI.

HYPOTHESIS

Female gender is not an independent predicor for mortality among STEMI patients.

METHODS

We performed a retrospective, single-center observational study that included 1346 consecutive STEMI patients undergoing PPCI, of which 1075 (80%) were male. Patient's records were evaluated for 30-day mortality, in-hospital complications, and long-term mortality over a mean period of 2.7 ± 1.6 years.

RESULTS

Compared with males, females were older (69 ± 13 vs 60 ± 13 years, P < 0.001), had a significantly higher rate of baseline risk factors, and had prolonged symptom duration (460 ± 815 minutes vs 367 ± 596 minutes, P = 0.03). Females suffered from more in-hospital complications and had higher 30-day mortality (5% vs 2%, P = 0.008) as well as higher overall mortality (12.5% vs 6%, P < 0.001). In spite of the significant mortality risk in unadjusted models, a multivariate adjusted Cox regression model did not demonstrate that female gender was an independent predictor for mortality among STEMI patients.

CONCLUSIONS

Among patients with STEMI treated by PPCI, female gender is associated with a higher 30-day mortality and complications rates compared to males. Following multivariate analysis, female gender was not a significant predictor of long-term death following STEMI.

ST-segment elevation myocardial infarction in China from 2001 to 2011 (the China PEACE-Retrospective Acute Myocardial Infarction Study): a retrospective analysis of hospital data

BACKGROUND

Despite the importance of ST-segment elevation myocardial infarction (STEMI) in China, no nationally representative studies have characterised the clinical profiles, management, and outcomes of this cardiac event during the past decade. We aimed to assess trends in characteristics, treatment, and outcomes for patients with STEMI in China between 2001 and 2011.

METHODS

In a retrospective analysis of hospital records, we used a two-stage random sampling design to create a nationally representative sample of patients in China admitted to hospital for STEMI in 3 years (2001, 2006, and 2011). In the first stage, we used a simple random-sampling procedure stratified by economic-geographical region to generate a list of participating hospitals. In the second stage we obtained case data for rates of STEMI, treatments, and baseline characteristics from patients attending each sampled hospital with a systematic sampling approach. We weighted our findings to estimate nationally representative rates and assess changes from 2001 to 2011. This study is registered with ClinicalTrials.gov, number NCT01624883.

FINDINGS

We sampled 175 hospitals (162 participated in the study) and 18,631 acute myocardial infarction admissions, of which 13,815 were STEMI admissions. 12,264 patients were included in analysis of treatments, procedures, and tests, and 11,986 were included in analysis of in-hospital outcomes. Between 2001 and 2011, estimated national rates of hospital admission for STEMI per 100,000 people increased (from 3·5 in 2001, to 7·9 in 2006, to 15·4 in 2011; ptrend<0·0001) and the prevalence of risk factors-including smoking, hypertension, diabetes, and dyslipidaemia-increased. We noted significant increases in use of aspirin within 24 h (79·7% [95% CI 77·9-81·5] in 2001 vs 91·2% [90·5-91·8] in 2011, ptrend<0·0001) and clopidogrel (1·5% [95% CI 1·0-2·1] in 2001 vs 82·1% [81·1-83·0] in 2011, ptrend<0·0001) in patients without documented contraindications. Despite an increase in the use of primary percutaneous coronary intervention (10·6% [95% CI 8·6-12·6] in 2001 vs 28·1% [26·6-29·7] in 2011, ptrend<0·0001), the proportion of patients who did not receive reperfusion did not significantly change (45·3% [95% CI 42·1-48·5] in 2001 vs 44·8% [43·1-46·5] in 2011, ptrend=0·69). The median length of hospital stay decreased from 12 days (IQR 7-18) in 2001 to 10 days (6-14) in 2011 (ptrend<0·0001). Adjusted in-hospital mortality did not significantly change between 2001 and 2011 (odds ratio 0·82, 95% CI 0·62-1·10, ptrend=0·07).

INTERPRETATION

During the past decade in China, hospital admissions for STEMI have risen; in these patients, comorbidities and the intensity of testing and treatment have increased. Quality of care has improved for some treatments, but important gaps persist and in-hospital mortality has not decreased. National efforts are needed to improve the care and outcomes for patients with STEMI in China.

FUNDING

National Health and Family Planning Commission of China.

Risk stratification for ST segment elevation myocardial infarction in the era of primary percutaneous coronary intervention

Acute coronary syndromes presenting with ST elevation are usually treated with emergency reperfusion/revascularisation therapy. In contrast current evidence and national guidelines recommend risk stratification for non ST segment elevation myocardial infarction (NSTEMI) with the decision on revascularisation dependent on perceived clinical risk. Risk stratification for STEMI has no recommendation. Statistical risk scoring techniques in NSTEMI have been demonstrated to improve outcomes however their uptake has been poor perhaps due to questions over their discrimination and concern for application to individuals who may not have been adequately represented in clinical trials. STEMI is perceived to carry sufficient risk to warrant emergency coronary intervention [by primary percutaneous coronary intervention (PPCI)] even if this results in a delay to reperfusion with immediate thrombolysis. Immediate thrombolysis may be as effective in patients presenting early, or at low risk, but physicians are poor at assessing clinical and procedural risks and currently are not required to consider this. Inadequate data on risk stratification in STEMI inhibits the option of immediate fibrinolysis, which may be cost-effective. Currently the mode of reperfusion for STEMI defaults to emergency angiography and percutaneous coronary intervention ignoring alternative strategies. This review article examines the current risk scores and evidence base for risk stratification for STEMI patients. The requirements for an ideal STEMI risk score are discussed.