Extracorporeal membrane oxygenation support in acute coronary syndromes complicated by cardiogenic shock

The impact of extracorporeal membrane oxygenation on mortality in patients with cardiogenic shock post-acute myocardial infarction: a systematic review and meta-analysis

Aims

Cardiogenic shock remains the leading cause of death in patients hospitalized with acute myocardial infarction. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used in the treatment of infarct-related cardiogenic shock. However, there is limited evidence regarding its beneficial impact on mortality. The aim of this study was to systematically review studies reporting the impact of VA-ECMO on mortality in patients with acute myocardial infarction complicated by cardiogenic shock.

Methods and results

A comprehensive search of medical databases (Cochrane Register and PubMed) was conducted. Studies that reported mortality outcomes in patients treated with VA-ECMO for infarct-related cardiogenic shock were included. The database search yielded 1194 results, of which 11 studies were included in the systematic review. Four of these studies, with a total of 586 patients, were randomized controlled trials and were included in the meta-analysis. This demonstrated that there was no significant difference in 30-day all-cause mortality with the use of VA-ECMO compared with standard medical therapy [odds ratio (OR) 0.91; 95% confidence interval (CI) 0.65-1.27]. Meta-analysis of two studies showed that VA-ECMO was associated with a significant reduction in 12-month all-cause mortality (OR 0.31; 95% CI 0.11-0.86). Qualitative synthesis of the observational studies showed that age, serum creatinine, serum lactate, and successful revascularization are independent predictors of mortality.

Conclusion

Veno-arterial extracorporeal membrane oxygenation does not improve 30-day all-cause mortality in patients with cardiogenic shock following acute myocardial infarction; however, there may be significant reduction in all-cause mortality at 12 months. Further studies are needed to delineate the potential benefit of VA-ECMO in long-term outcomes.

Registration

The protocol was registered in the PROSPERO International Prospective Register of Systematic Reviews (ID: CRD42023461740).

Limb Amputation Following Extracorporeal Membrane Oxygenation Therapy Among Survivors: A Nationwide Cohort Study from South Korea

We aimed to investigate the incidence of limb amputation due to vascular complications related to extracorporeal membrane oxygenation (ECMO) therapy among survivors and examine its association with long-term mortality in these cases. Data from the National Health Insurance Service database in South Korea were extracted for this population-based cohort study. Adult people who underwent ECMO therapy between 2005 and 2018 were included. ECMO survivors were defined as those who survived for at least 365 days after the initiation of ECMO therapy. A total of 6,968 ECMO survivors were included in the study. Among them, 114 (1.6%) underwent limb amputation within 365 days of starting ECMO therapy. On multivariable Cox regression analysis, the risk of 3-year all-cause mortality was not significantly associated with limb amputation compared with those without limb amputation (hazard ratio: 1.53; 95% CI: 0.89-2.63; P = 0.072). In South Korea, 1.6% of ECMO survivors underwent limb amputation within 365 days after initiating ECMO therapy; however, it was not significantly associated with the 3-year all-cause mortality. Our findings warrant future studies on the impact on the quality of life and morbidity-related implications among patients who undergo limb amputation due to ECMO therapy.

Proposal for a trial of early left ventricular venting during venoarterial extracorporeal membrane oxygenation for cardiogenic shock

Objective

Patients with profound cardiogenic shock may require venoarterial (VA) extracorporeal membrane oxygenation (ECMO) for circulatory support most commonly via the femoral vessels. The rate of cardiac recovery in this population remains low, possibly because peripheral VA-ECMO increases ventricular afterload. Whether direct ventricular unloading in peripheral VA-ECMO enhances cardiac recovery is unknown, but is being more frequently utilized. A randomized trial is warranted to evaluate the clinical effectiveness of percutaneous left ventricle venting to enhance cardiac recovery in the setting of VA-ECMO.

Methods

We describe the rationale, design, and initial testing of a randomized controlled trial of VA-ECMO with and without percutaneous left ventricle venting using a percutaneous micro-axial ventricular assist device.

Results

This is an ongoing prospective randomized controlled trial in adult patients with primary cardiac failure presenting in cardiogenic shock requiring peripheral VA-ECMO, designed to test the safety and effectiveness of percutaneous left ventricle venting in improving the rate of cardiac recovery.

Conclusions

The results of this nonindustry-sponsored trial will provide critical information on whether left ventricle unloading in peripheral VA-ECMO is safe and effective.

Current Landscape of Temporary Percutaneous Mechanical Circulatory Support Technology

Mechanical circulatory support devices provide hemodynamic support to patients who present with cardiogenic shock. These devices work using different mechanisms to provide univentricular or biventricular support. There is a growing body of evidence supporting use of these devices as a goal for cardiac recovery or as a bridge to definitive therapy, but definitive, well-powered studies are still needed. Mechanical circulatory support devices are increasingly used using shock team and protocols, which can help clinicians in decision making, balancing operator and institutional experience and expertise. The aim of this article is to review commercially available mechanical circulatory support devices, their profiles and mechanisms of action, and the evidence available regarding their use.

Overview of Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO) Support for the Management of Cardiogenic Shock

Cardiogenic shock accounts for ~100,000 annual hospital admissions in the United States. Despite improvements in medical management strategies, in-hospital mortality remains unacceptably high. Multiple mechanical circulatory support devices have been developed with the aim to provide hemodynamic support and to improve outcomes in this population. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is the most advanced temporary life support system that is unique in that it provides immediate and complete hemodynamic support as well as concomitant gas exchange. In this review, we discuss the fundamental concepts and hemodynamic aspects of VA-ECMO support in patients with cardiogenic shock of various etiologies. In addition, we review the common indications, contraindications and complications associated with VA-ECMO use.

Understanding the "extracorporeal membrane oxygenation gap" in veno-arterial configuration for adult patients: Timing and causes of death

Timing and causes of hospital mortality in adult patients undergoing veno‐arterial extracorporeal membrane oxygenation (V‐A ECMO) have been poorly described. Aim of the current review was to investigate the timing and causes of death of adult patients supported with V‐A ECMO and subsequently define the “V‐A ECMO gap,” which represents the patients who are successfully weaned of ECMO but eventually die during hospital stay. A systematic search was performed using electronic MEDLINE and EMBASE databases through PubMed. Studies reporting on adult V‐A ECMO patients from January 1993 to December 2020 were screened. The studies included in this review were studies that reported more than 10 adult, human patients, and no mechanical circulatory support other than V‐A ECMO. Information extracted from each study included mainly mortality and causes of death on ECMO and after weaning. Complications and discharge rates were also extracted. Sixty studies with 9181 patients were included for analysis in this systematic review. Overall mortality was 38.0% (95% confidence intervals [CIs] 34.2%‐41.9%) during V‐A ECMO support (reported by 60 studies) and 15.3% (95% CI 11.1%‐19.5%, reported by 57 studies) after weaning. Finally, 44.0% of patients (95% CI 39.8‐52.2) were discharged from hospital (reported by 60 studies). Most common causes of death on ECMO were multiple organ failure, followed by cardiac failure and neurological causes. More than one‐third of V‐A ECMO patients die during ECMO support. Additionally, many of successfully weaned patients still decease during hospital stay, defining the “V‐A ECMO gap.” Underreporting and lack of uniformity in reporting of important parameters remains problematic in ECMO research. Future studies should uniformly define timing and causes of death in V‐A ECMO patients to better understand the effectiveness and complications of this support.

A Systematic Literature Review of Packed Red Cell Transfusion Usage in Adult Extracorporeal Membrane Oxygenation

Background: Blood product administration plays a major role in the management of patients treated with extracorporeal membrane oxygenation (ECMO) and may be a contributor to morbidity and mortality. Methods: We performed a systematic review of the published literature to determine the current usage of packed red cell transfusions. Predefined search criteria were used to identify journal articles reporting transfusion practice in ECMO by interrogating EMBASE and Medline databases and following the PRISMA statement. Results: Out of 1579 abstracts screened, articles reporting ECMO usage in a minimum of 10 adult patients were included. Full texts of 331 articles were obtained, and 54 were included in the final analysis. All studies were observational (2 were designed prospectively, and two were multicentre). A total of 3808 patients were reported (range 10–517). Mean exposure to ECMO was 8.2 days (95% confidence interval (CI) 7.0–9.4). A median of 5.6% was not transfused (interquartile range (IQR) 0–11.3%, 19 studies). The mean red cell transfusion per ECMO run was 17.7 units (CI 14.2–21.2, from 52 studies) or 2.60 units per day (CI 1.93–3.27, from 49 studies). The median survival to discharge was 50.8% (IQR 40.0–64.9%). Conclusion: Current evidence on transfusion practice in ECMO is mainly drawn from single-centre observational trials and varies widely. The need for transfusions is highly variable. Confounding factors influencing transfusion practice need to be identified in prospective multicentre studies to mitigate potential harmful effects and generate hypotheses for interventional trials.

Mechanical Circulatory Support in Acute Myocardial Infarction and Cardiogenic Shock

Mechanical circulatory support devices are increasingly used for the treatment of acute myocardial infarction complicated by cardiogenic shock. These devices provide different levels of univentricular and biventricular support, have different mechanisms of actions, and provide different physiologic effects. Institutions require expert teams to safely implant and manage these devices. This article reviews the mechanism of action, physiologic effects, and data as they relate to the utilization of these devices.

Blood lactate predicts survival after percutaneous implantation of extracorporeal life support for refractory cardiac arrest or cardiogenic shock complicating acute coronary syndrome: insights from the CareGem registry

Refractory cardiogenic shock (RCS) or refractory cardiac arrest (RCA) complicating acute coronary syndrome (ACS) is associated with extremely high mortality rate. Veno-arterial extracorporeal life support (VA-ECLS) represents a valuable therapeutic option to stabilize patients' condition before or at the time of emergency revascularization. We analyzed 29 consecutive patients with RCS or RCA complicating ACS, and implanted with VA-ECLS in two centers who have adopted a similar, structured approach to ECLS implantation. Data were collected from January 2010 to December 2015 and ECLS had to be percutaneously implanted either before (within 48 h) or at the time of attempted percutaneous coronary revascularization (PCI). We investigated in-hospital outcome and factors associated with survival. Twenty-one (72%) were implanted for RCA, whereas 8 (28%) were implanted on ECLS for RCS. All RCA were witnessed and no-flow time was shorter than 5 min in all cases but one. All patients underwent attempted emergency PCI, using radial access in ten cases (34.5%), whereas in three patients a subsequent CABG was performed. Overall, ten patients (34.5%) survived, nine of them with a good neurological outcome. Life threatening complications, including stroke (4 pts), leg ischemia (4 pts), intestinal ischemia (5 pts), and deep vein thrombosis 2 pts), occurred frequently, but were not associated with in-hospital death. Main cause of death was multi-organ failure. PCI variables did not predict survival. Survivors were younger, with shorter low-flow time, and with ECLS mainly implanted for RCS. At multivariate analysis, levels of lactate at ECLS implantation (OR 4.32, 95%CI 1.01-18.51, p = 0.049) emerged as the only variable that independently predicted survival. In patients with RCA or RCS complicating ACS who are percutaneously implanted with ECLS before or at the time of coronary revascularization, in hospital survival rate is higher than 30%. Level of lactate at ECLS implantation appears to be the most important factor to predict survival.

Platelet transfusion is associated with 90-day and 1-year mortality for adult patients requiring veno-arterial extracorporeal membrane oxygenation

BACKGROUND

Studies examining one-year mortality respecting component blood transfusion are sparse. We hypothesize that component blood product transfusions are negatively associated with 90-day and 1-year survival for all patients requiring veno-arterial (VA) or veno-venous (VV) ECMO.

STUDY DESIGN AND METHODS

This was an IRB-approved retrospective cohort analysis of 676 consecutive patients requiring ECMO at the University of Pittsburgh between 2005 and 2016. Patients were analysed both as an entire cohort and as two subsets with respect to ECMO modality (VA vs. VV). Additional data collected and analysed included patient characteristics, laboratory values and blood product transfusion.

RESULTS

Multivariable analysis revealed that platelet transfusion was associated with 90-day mortality (OR: 1·05, P = 0·037) and one-year mortality for the entire cohort (OR = 1·05, P = 0·046,). Platelet transfusion volume was also associated with mortality in the VA-ECMO subset of patients at both 90 days (OR = 1·08, P = 0·03) and one year (OR: 1·11, P = 0·014). Age, peak International Normalized Raton ECMO, nadir haemoglobin (on ECMO) and final haemoglobin (after ECMO) were significantly associated with mortality for patients requiring VA-ECMO. For VV-ECMO patients, age, INR and peak creatinine on ECMO were associated with mortality. No individual component blood product was associated with one-year mortality for patients requiring VV-ECMO.

CONCLUSION

Platelet transfusion was associated with increased 90-day and 1-year mortality for patients requiring VA-ECMO.

Currently Available Options for Mechanical Circulatory Support for the Management of Cardiogenic Shock

Cardiogenic shock (CS) is a complex condition with a high risk for morbidity and mortality. Mechanical circulatory support (MCS) devices were developed to support patients with CS in cases refractory to treatment with vasoactive medications. Current devices include intra-aortic balloon pumps, intravascular microaxial pumps, percutaneous LVAD, percutaneous RVAD, and VA ECMO. Data from limited observational studies and clinical trials show a clear difference in the level of hemodynamic support offered by each device. However, at this point, there are insufficient clinical trial data to guide MCS selection and, until ongoing clinical trials are completed, use of the right device for the right patient depends largely on clinical judgment.

Coronary Artery Bypass Grafting in Cardiogenic Shock: Decision-Making, Management Options, and Outcomes

Coronary artery bypass grafting is a highly efficacious mode of myocardial revascularization that reduces mortality from ischemic heart disease. The patient presenting after acute myocardial infarction in cardiogenic shock presents a unique challenge. Early revascularization is proven to reduce mortality, but many questions remain, including the optimal mode and extent of revascularization, the role of mechanical circulatory support, and which patients are candidates for surgical intervention. Unprecedented attention to the outcomes of cardiac surgery means decisions about the management of the acute myocardial infarction in cardiogenic shock patients are influenced by risk aversion. The authors here review this topic to arm the reader with a comprehensive understanding of the literature to better guide surgical decision-making and perioperative management.

The science of safety: complications associated with the use of mechanical circulatory support in cardiogenic shock and best practices to maximize safety

Acute mechanical circulatory support (MCS) devices are widely used in cardiogenic shock (CS) despite a lack of high-quality clinical evidence to guide their use. Multiple devices exist across a spectrum from modest to complete support, and each is associated with unique risks. In this review, we summarize existing data on complications associated with the three most widely used acute MCS platforms: the intra-aortic balloon pump (IABP), Impella systems, and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). We review evidence from available randomized trials and highlight challenges comparing complication rates from case series and comparative observational studies where a lack of granular data precludes appropriate matching of patients by CS severity. We further offer a series of best practices to help shock practitioners minimize the risk of MCS-associated complications and ensure the best possible outcomes for patients.

Association between the Door-to-balloon Time and Mid-term Clinical Outcomes in Patients with ST-Segment Elevation Myocardial Infarction

Objective In primary percutaneous coronary intervention (PCI), the door-to-balloon time (DTBT) is known to be associated with in-hospital death in patients with ST-segment elevation myocardial infarction (STEMI). However, little is known regarding the association between the DTBT and the mid-term clinical outcomes in patients with STEMI. The purpose of this study was to investigate the association between the DTBT and mid-term all-cause death. Methods The study population included 309 STEMI patients, who were divided into the short DTBT (DTBT<60 minutes, n=103), intermediate DTBT (DTBT 60-120 minutes, n=174) and long DTBT (DTBT >120 minutes, n=32) groups. The median follow-up period was 287 days (interquartile range: 182-624 days). Results The incidence of all-cause death in the long DTBT group was significantly higher in comparison to the other groups (p<0.001). In the multivariate Cox regression analysis, although a short DTBT [vs. intermediate DTBT: hazard ratio (HR) 1.00, 95% confidence interval (CI) 0.39-2.55, p=0.99] was not associated with all-cause death, a long DTBT (vs. intermediate DTBT: HR 2.80, 95% CI 1.26-6.17, p=0.011) was significantly associated with all-cause death, after controlling for confounding factors such as Killip class 4, an impaired renal function, and the number of diseased vessels. Conclusion The DTBT was significantly associated with the incidence of mid-term all-cause death. Our results support the strong adherence to the DTBT in patients with STEMI.

Circulatory Support with Extracorporeal Membrane Oxygenation and/or Impella for Cardiogenic Shock During Myocardial Infarction

Temporary mechanical circulatory support (TCS) is recommended for patients with profound cardiogenic shock (CS). Extracorporeal membrane oxygenation (ECMO) and Impella are possible TCS devices, but the device choice and the implantation timing are not definitely established, specifically during acute myocardial infarction. We have analyzed the respective use of ECMO or Impella (2.5, CP, or 5.0) for CS following acute myocardial infarction, from a cohort of patients who underwent TCS within 72 hours after admission for emergency percutaneous coronary intervention (PCI) from January 2009 to April 2015. Among 88 TCS-treated patients, 42 had early TCS: 23 ECMO and 19 Impella. Cardiac management, including PCI, was similar between the two groups, but ECMO patients were sicker than Impella patients (higher blood lactate level at ICU admission, higher vasoactive-inotroic and ENCOURAGE scores before TCS implantation, p ≤ 0.02). Three patients (7%) have had TCS implantation before admission, but TCS was implanted mostly in cathlab (43%, 1 during PCI, 13 just after PCI) or soon after ICU admission (50%, n = 21). Modification of the initial TCS choice was required in 10 cases (24%) for assistance upgrading in case of Impella (n = 4) or for left ventricle unloading in case of ECMO (n = 6). Extracorporeal membrane oxygenation is the technique of choice in case of profound CS, whereas Impella devices seem more appropriate for less severe hemodynamic compromise. Interestingly, the combination of both techniques may help to overcome the limits inherent to each device.

Utilization of Percutaneous Mechanical Circulatory Support Devices in Cardiogenic Shock Complicating Acute Myocardial Infarction and High-Risk Percutaneous Coronary Interventions

Given the tremendous progress in interventional cardiology over the last decade, a growing number of older patients, who have more comorbidities and more complex coronary artery disease, are being considered for technically challenging and high-risk percutaneous coronary interventions (PCI). The success of performing such complex PCI is increasingly dependent on the availability and improvement of mechanical circulatory support (MCS) devices, which aim to provide hemodynamic support and left ventricular (LV) unloading to enable safe and successful coronary revascularization. MCS as an adjunct to high-risk PCI may, therefore, be an important component for improvement in clinical outcomes. MCS devices in this setting can be used for two main clinical conditions: patients who present with cardiogenic shock complicating acute myocardial infarction (AMI) and those undergoing technically complex and high-risk PCI without having overt cardiogenic shock. The current article reviews the advancement in the use of various devices in both AMI complicated by cardiogenic shock and complex high-risk PCI, highlights the available hemodynamic and clinical data associated with the use of MCS devices, and presents suggestive management strategies focusing on appropriate patient selection and optimal timing and support to potentially increase the clinical benefit from utilizing these devices during PCI in this high-risk group of patients.

Limb ischemia in peripheral veno-arterial extracorporeal membrane oxygenation: a narrative review of incidence, prevention, monitoring, and treatment

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is an increasingly adopted life-saving mechanical circulatory support for a number of potentially reversible or treatable cardiac diseases. It is also started as a bridge-to-transplantation/ventricular assist device in the case of unrecoverable cardiac or cardio-respiratory illness. In recent years, principally for non-post-cardiotomy shock, peripheral cannulation using the femoral vessels has been the approach of choice because it does not need the chest opening, can be quickly established, can be applied percutaneously, and is less likely to cause bleeding and infections than central cannulation. Peripheral ECMO, however, is characterized by a higher rate of vascular complications. The mechanisms of such adverse events are often multifactorial, including suboptimal arterial perfusion and hemodynamic instability due to the underlying disease, peripheral vascular disease, and placement of cannulas that nearly occlude the vessel. The effect of femoral artery damage and/or significant reduced limb perfusion can be devastating because limb ischemia can lead to compartment syndrome, requiring fasciotomy and, occasionally, even limb amputation, thereby negatively impacting hospital stay, long-term functional outcomes, and survival. Data on this topic are highly fragmentary, and there are no clear-cut recommendations. Accordingly, the strategies adopted to cope with this complication vary a great deal, ranging from preventive placement of antegrade distal perfusion cannulas to rescue interventions and vascular surgery after the complication has manifested.This review aims to provide a comprehensive overview of limb ischemia during femoral cannulation for VA-ECMO in adults, focusing on incidence, tools for early diagnosis, risk factors, and preventive and treating strategies.

Mechanical Left Ventricular Unloading to Reduce Infarct Size During Acute Myocardial Infarction: Insight from Preclinical and Clinical Studies

Acute myocardial infarction (AMI) remains a leading cause of morbidity and mortality. Pioneering preclinical work reported by Peter Maroko and Eugene Braunwald in 1971 identified oxygen supply and demand are primary determinants of myocardial infarct size in the setting of a heart attack. Since the 1950s, advances in mechanical engineering led to the development of short-term circulatory support devices that range from pulsatile to continuous flow pumps. The primary objective of these pumps is to reduce native heart work, enhance coronary blood flow, and sustain systemic perfusion. Whether these pumps could reduce myocardial infarct size in the setting of AMI became an intense focus for preclinical investigation with variable animal models, experimental algorithms, and pump platforms being tested. In this review, we discuss the design of these preclinical studies and the evolution of mechanical support platforms and attempt to translate these experimental methods into clinical trials.

Veno-arterial extracorporeal membrane oxygenation in addition to primary PCI in patients presenting with ST-elevation myocardial infarction

Introduction

Primary percutaneous coronary intervention (pPCI) in ST-elevation myocardial infarction (STEMI) can cause great haemodynamic instability. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) can provide haemodynamic support in patients with STEMI but data on outcome and complications are scarce.

Methods

An in-hospital registry was conducted enrolling all patients receiving VA-ECMO. Patients were analysed for medical history, mortality, neurological outcome, complications and coronary artery disease.

Results

Between 2011 and 2016, 12 patients underwent pPCI for STEMI and received VA-ECMO for haemodynamic support. The majority of the patients were male (10/12) with a median age of 63 (47–75) years and 4 of the 12 patients had a history of coronary artery disease. A cardiac arrest was witnessed in 11 patients. The left coronary artery was compromised in 8 patients and 4 had right coronary artery disease. All patients were in Killip class IV. Survival to discharge was 67% (8/12), 1‑year survival was 42% (5/12), 2 patients have not yet reached the 1‑year survival point but are still alive and 1 patient died within a year after discharge. All-cause mortality was 42% (5/12) of which mortality on ECMO was 33% (4/12). Patient-related complications occurred in 6 of the 12 patients: 1 patient suffered major neurological impairment, 2 patients suffered haemorrhage at the cannula site, 2 patients had limb ischaemia and 1 patient had a haemorrhage elsewhere. There were no VA-ECMO hardware malfunctions.

Conclusion

VA-ECMO in pPCI for STEMI has a high survival rate and neurological outcome is good, even when the patient is admitted with a cardiac arrest.

Medication Complications in Extracorporeal Membrane Oxygenation

The need for extracorporeal membrane oxygenation (ECMO) therapy is a marker of disease severity for which multiple medications are required. The therapy causes physiologic changes that impact drug pharmacokinetics. These changes can lead to exposure-driven decreases in efficacy or increased incidence of side effects. The pharmacokinetic changes are drug specific and largely undefined for most drugs. We review available drug dosing data and provide guidance for use in the ECMO patient population.

Electrocardiographic characteristics associated with in-hospital outcome in patients with left main acute coronary syndrome: For contriving a new risk stratification score

AIM

The aim of this study was to evaluate electrocardiographic characteristics associated with in-hospital prognosis in patients with left main acute coronary syndrome.

METHODS AND RESULTS

A total of 89 left main acute coronary syndrome subjects were selected from 3357 consecutive acute coronary syndrome patients (2.7%). Patients of this study were divided into two groups; those who survived and those who died. Patients' characteristics and electrocardiogram on admission were then retrospectively analyzed between the two groups. In-hospital mortality was 28.1%. The prevalence and degree of ST-segment elevation at lead aVL were significantly higher in the deceased group than in the survival group ( p<0.001). However, those at lead aVR did not show significant differences between the two groups. Moreover, the width of the QRS-complex was significantly wider (lead V3; p<0.001), and the level of five minus the absolute value of five minus number of ST-segment elevation (5-|5-ST|; due to the highest in-hospital mortality (70%) in the five-lead ST-segment elevation group) was significantly larger in the deceased group than in the survival group ( p<0.001). The odds ratios that predicted in-hospital cardiac death were 1.03 for width of the QRS-complex at lead V3 (95% confidence interval (CI); 1.01-1.06; p=0.003), 1.74 for 5-|5-ST| (95% CI; 1.03-3.00; p=0.040), and 1.44 for ST-segment elevation at lead aVL (95% CI; 0.93-2.23; p=0.100).

CONCLUSIONS

ST-segment elevation at lead aVL rather than aVR, width of the QRS-complex at lead V3 and number of ST-segment elevation were the prognostic predictors for in-hospital mortality in patients with left main acute coronary syndrome. Electrocardiographic characteristics should be assessed in addition to the established risk score in patients with left main acute coronary syndrome.

The role of acute circulatory support in ST-segment elevation myocardial infarction complicated by cardiogenic shock

In the setting of ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock, three primary treatment objectives include providing circulatory support, ventricular unloading, and restoring myocardial perfusion. In addition to primary percutaneous coronary intervention, each of these three objectives can be achieved with appropriate use of an acute mechanical circulatory support (AMCS) pump. Over the past decade, utilization of percutaneously-delivered AMCS devices including the Impella axial-flow catheter, TandemHeart left atrial-to-femoral artery bypass system, and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has grown exponentially. In this review, we will discuss the hemodynamic impact of each AMCS device and clinical data surrounding their use in the setting of STEMI complicated by cardiogenic shock.

Survival Analysis After Extracorporeal Membrane Oxygenation in Critically Ill Adults

Background—

Extracorporeal membrane oxygenation (ECMO) provides circulatory and respiratory support for patients with severe acute cardiopulmonary failure. The objective of this study was to examine the survival outcomes for patients who received ECMO.

Methods and Results—

Adult patients who received ECMO from September 1, 2002, to December 31, 2012, were identified from the Taiwan National Health Insurance Database associated with coronary artery bypass graft surgery, myocardial infarction/cardiogenic shock, injury, and infection/septic shock. A Cox regression model was used to determine hazard ratios and to compare 30-day and 1-year survival rates with the myocardial infarction/cardiogenic shock group used as the reference. The mean±SD age of the 4227-patient cohort was 57±17 years, and 72% were male. The overall mortalities were 59.8% and 76.5% at 1 month and 1 year. Survival statistics deteriorated sharply when ECMO was required for >3 days. Acute (30-day) survival was more favorable in the infection/septic shock (n=1076; hazard ratio, 0.61; 95% confidence interval, 0.55–0.67), coronary artery bypass graft surgery (n=1077; hazard ratio, 0.68; 95% confidence interval, 0.61–0.75), and injury (n=369, hazard ratio, 0.82; 95% confidence interval, 0.70–0.95) groups. The extended survival rapidly approached an asymptote near 20% for the infection/septic shock, myocardial infarction/cardiogenic shock (n=1705), and coronary artery bypass graft surgery groups. The pattern of survival for the injury group was somewhat better, exceeding 30% at year-end.

Conclusions—

Regardless of initial pathology, patients requiring ECMO were critically ill with similar guarded prognoses. Those in the trauma group had somewhat better outcomes. Determining the efficacy and cost-effectiveness of ECMO should be a critical future goal.

Acute Myocardial Infarction/Thrombectomy

This article focuses on specialized techniques and devices used in the most challenging cases of acute myocardial infarction. Areas where high-quality evidence is either clear or absent are avoided. Controversies in the use of support or thrombectomy devices, the addition of adjunct pharmacology, and the decision to treat nonculprit lesions are discussed. Recent years have seen a shift in guidelines to downgrading the use of assist devices in cardiogenic shock and aspiration thrombectomy, whereas consideration of nonculprit coronary intervention has been revived. These changes come in the wake of a series of large, practice-changing clinical trials.

Extracorporeal membrane oxygenation (ECMO) for critically ill adults in the emergency department: history, current applications, and future directions

Extracorporeal membrane oxygenation (ECMO) is a mode of extracorporeal life support that augments oxygenation, ventilation and/or cardiac output via cannulae connected to a circuit that pumps blood through an oxygenator and back into the patient. ECMO has been used for decades to support cardiopulmonary disease refractory to conventional therapy. While not robust, there are promising data for the use of ECMO in acute hypoxemic respiratory failure, cardiac arrest, and cardiogenic shock and the potential indications for ECMO continue to increase. This review discusses the existing literature on the potential use of ECMO in critically ill patients within the emergency department.

Outcome in Patients Having Salvage Coronary Artery Bypass Grafting

Salvage coronary artery bypass grafting (CABG) is often performed for cardiogenic shock on compassionate basis without clinical data justifying this aggressive approach. The aim of this study was to analyze early and intermediate outcomes after salvage CABG. We retrospectively reviewed the data of 85 patients who underwent salvage CABG at 11 European cardiac surgery centers. Salvage CABG was defined according to the EuroSCORE criteria, that is, a procedure performed in patients requiring cardiopulmonary resuscitation (external cardiac massage) en route to the operating theater or before induction of anesthesia. A percutaneous coronary intervention procedure preceded salvage CABG in 55 patients (64.7%). Thirty patients (35.3%) died during the inhospital stay. The mean EuroSCORE II was 32.0% and the observed-to-expected ratio was 1.08. Salvage CABG was associated with high rates of postoperative stroke (9.4%), resternotomy for bleeding (23.5%), resternotomy for hemodynamic instability (15.3%), dialysis (18.8%), severe gastrointestinal complications (12.9%), and deep sternal wound infection (10.6%). Survival at 1, 3, and 5 years was 58.6%, 49.8%, and 40.9%, respectively. Twenty patients (23.5%) were postoperatively treated with extracorporeal membrane oxygenation (ECMO). The rates of adverse events after ECMO were particularly high (stroke 40%, resternotomy for bleeding 60%, dialysis 35%, gastrointestinal complications 30%, and deep sternal wound infection 30%). Of patients treated with ECMO, 8 (40%) survived to discharge, and 1-year survival was 29.2%. Salvage CABG is associated with high risk of immediate mortality and severe adverse events. However, the observed immediate and intermediate outcome justify coronary surgery in these critically ill patients. A number of these patients are currently treated by ECMO, and its results are encouraging.