Mild Hypothermia in Cardiogenic Shock Complicating Myocardial Infarction

Prognosis of refractory cardiogenic shock in de-novo versus acute-on-chronic heart failure: Insights from the HYPO-ECMO trial

BACKGROUND

Acute-on-chronic heart failure (ACHF) currently represents the leading etiology of cardiogenic shock (CS). We aimed to assess the prognostic value of history of heart failure (HF) in patients with refractory CS as well as its effect on the benefit of moderate hypothermia (MH) (33-34 °C).

METHODS

Of the 334 patients included in the HYPO-ECMO trial, 321 (96 %) had available HF history information, among whom 65 (20 %) had prior HF. Inverse probability weighting (IPW) was used to compare ACHF patients and de-novo HF (DNHF) patients. Primary outcome was all-cause mortality at day 30. Main secondary outcomes were mortality and the composite of death, heart transplant, escalation to left ventricular assist device, or stroke up to day 180.

RESULTS

At 30 days, 26 patients (40.0 %) died in the ACHF group versus 122 patients (47.7 %) in the DNHF group (crude risk difference (RD), -7.7 % [-21.0 to 5.7] p = 0.26; IPW RD, -11.6 % [-24.8 to 1.6] p = 0.084). Mortality (IPW RD, -13.7 % [-27.1 to -0.2], p = 0.047) and the composite outcome (IPW RD, -19.5 % [-32.9 to -6.1], p = 0.004) were significantly lower at day 180 in the ACHF group. Patients randomized to MH tended to have a lower risk for the primary outcome (RD -10.9 %, [-23.1 to 1.2], p = 0.078) and a significant reduction in composite outcome (p < 0.05 at each timepoint) in the DNHF group but not in the ACHF group, despite the absence of a significant interaction (p > 0.05).

CONCLUSIONS

In VA-ECMO-treated CS, ACHF was associated with comparable 30-day survival but lower 180-day mortality and morbidity-mortality. In this exploratory post-hoc analysis, MH appeared to be associated with improved outcomes in DNHF patients only.

CLINICALTRIALS

gov Identifier: NCT02754193.

The Comparative Epidemiology, Pathophysiology and Management of Cardiogenic Shock Associated With Acute Myocardial Infarction and Advanced Heart Failure

Cardiogenic shock (CS) results from low cardiac output caused by myocardial dysfunction, coupled with systemic end-organ tissue hypoperfusion and elevated ventricular filling pressures, along a spectrum of shock severity. This narrative review aims to compare the epidemiology, pathophysiology, and contemporary management of 2 common etiologies of CS caused by acute myocardial infarction (AMI-CS) and advanced heart failure (HF-CS). CS complicates up to 14% of AMI and 5% of HF admissions. Rapid therapeutic intervention after prompt recognition of CS etiology is the mainstay toward improving clinical outcomes and mitigating end-organ sequelae and death. In AMI-CS, persistent hypotension often leads to subsequent hypoperfusion and congestion, and early culprit coronary artery lesion revascularization is critical. In HF-CS, congestion often precedes hypoperfusion and hypotension, and targeting the underlying nonischemic cause of myocardial dysfunction is key. Tailoring of hemodynamic strategies with vasoactive agents and temporary mechanical circulatory and end-organ support to manage the predominant ventricular failure, hemometabolic phenotypes, and shock severity associated with each etiology is discussed. Given the limited evidence-base in CS care, we also highlight potential knowledge gaps ripe for future exploration.

Gut-derived macrophages link intestinal damage to brain injury after cardiac arrest through TREM1 signaling

Brain injury is the leading cause of death and disability in survivors of cardiac arrest, where neuroinflammation triggered by infiltrating macrophages plays a pivotal role. Here, we seek to elucidate the origin of macrophages infiltrating the brain and their mechanism of action after cardiac arrest/cardiopulmonary resuscitation (CA/CPR). Wild-type or photoconvertible Cd68-Cre:R26-LSL-KikGR mice were subjected to 10-min CA/CPR, and the migration of gut-derived macrophages into brain was assessed. Transcriptome sequencing was performed to identify the key proinflammatory signal of macrophages infiltrating the brain, triggering receptor expressed on myeloid cells 1 (TREM1). Upon drug intervention, the effects of TREM1 on post-CA/CPR brain injury were further evaluated. 16S rRNA sequencing was used to detect gut dysbiosis after CA/CPR. Through photoconversion experiments, we found that small intestine-derived macrophages infiltrated the brain and played a crucial role in triggering secondary brain injury after CA/CPR. The infiltrating peripheral macrophages showed upregulated TREM1 levels, and we further revealed the crucial role of gut-derived TREM1+ macrophages in post-CA/CPR brain injury through a drug intervention targeting TREM1. Moreover, a close correlation between upregulated TREM1 expression and poor neurological outcomes was observed in CA survivors. Mechanistically, CA/CPR caused a substantial expansion of Enterobacter at the early stage, which ignited intestinal TREM1 signaling via the activation of Toll-like receptor 4 on macrophages through the release of lipopolysaccharide. Our findings reveal essential crosstalk between the gut and brain after CA/CPR and underscore the potential of targeting TREM1+ small intestine-derived macrophages as a novel therapeutic strategy for mitigating post-CA/CPR brain injury.

Therapeutic hypothermia in patients with acute myocardial infarction complicated by out-of-hospital cardiac arrest

BACKGROUND

There is a lack of data regarding outcomes of therapeutic hypothermia in patients with acute myocardial infarction (AMI) complicated by out-of-hospital cardiac arrest (OHCA). This study aimed to evaluate the effect of therapeutic hypothermia on clinical outcomes in comatose patients after percutaneous coronary intervention (PCI) for AMI following OHCA.

METHODS

Using a prospective nationwide registry from 2016 to 2021, we selected 2925 patients with AMI who underwent emergency PCI among 182,508 OHCA cases. These patients were divided into groups receiving hypothermia treatment (n = 624) and those not receiving hypothermia treatment (n = 2301). The primary endpoint was in-hospital mortality, and secondary endpoints were mortality rate at 24 h and neurological outcomes at discharge.

RESULTS

The hypothermia group showed a significantly lower rate of in-hospital mortality than the non-hypothermia group (odds ratio [OR] 0.71; 95% confidence interval [CI], 0.59-0.85; P < 0.001). However, there was no significant difference in neurological outcomes at discharge between the two groups. Furthermore, quartile analysis of door-to-cooling (DtC) time, defined as the time from hospital arrival to initiation of hypothermia, demonstrated that a shorter DtC time was associated with a decreased risk of mortality and poor neurological outcomes (mortality: adjusted OR, 0.40; 95% CI, 0.30-0.54; P < 0.001; poor neurological outcome: adjusted OR, 0.59; 95% CI, 0.45-0.77; P < 0.001 for quartile 1 versus quartile 4).

CONCLUSIONS

Therapeutic hypothermia reduced the rate of in-hospital mortality in patients with AMI complicated by OHCA. Moreover, early initiation of hypothermia demonstrated a reduction in mortality and poor neurological outcomes.

PRE-REGISTERED CLINICAL TRIAL NUMBER

URL: http://clinicaltrials.gov . Unique identifier: NCT05724914. In this large, government-controlled, nationwide, prospective real-world registry with AMI and complicated by OHCA, we demonstrated therapeutic hypothermia reduced the rate of in-hospital mortality, but it did not improve neurological outcomes at discharge. Our findings also showed that early initiation of hypothermia was significantly associated with reduced in-hospital mortality and poor neurological outcomes. The findings of this study suggest that therapeutic hypothermia reduces in-hospital mortality in patients with AMI complicated by OHCA. Early application of hypothermia should be considered as a potential means of improving neurological outcomes in patients with AMI-OHCA undergoing emergency PCI.

Comparison of hypothermic and normothermic targeted temperature management in out-of-hospital cardiac arrest patients with acute coronary syndrome: a nationwide retrospective study

BACKGROUND

Targeted temperature management (TTM) is considered a beneficial treatment for improving outcomes in patients with OHCA due to acute coronary syndrome (ACS). The comparative benefits of hypothermic TTM (32-34°C) versus normothermic TTM (35-36°C) are unclear. This study compares these TTM strategies in improving neurological outcomes and survival rates in OHCA patients with ACS.

METHODS

We conducted a retrospective analysis using data from the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest (JAAM-OHCA) registry, encompassing 68,110 OHCA patients between June 2014 and December 2020. After applying inclusion and exclusion criteria, 1,217 adult patients with ACS who received TTM were eligible for the study. Patients were categorized into two groups based on their TTM strategy: hypothermic TTM (32-34°C) and normothermic TTM (35-36°C). The primary outcome was 30-day favorable neurological outcome, defined by the Cerebral Performance Category (CPC) scale (CPC 1-2). Secondary outcomes included 30-day survival and adverse event incidence. Statistical analysis involved multivariable logistic regression and propensity score adjustments with inverse probability weighting (IPW) to account for potential confounders.

RESULTS

Of the 1,217 patients, 369 received normothermic TTM and 848 received hypothermic TTM. In both groups, most patients were male, with a median age in the 60s. Approximately 70% had a shockable rhythm at the scene, one-third had a shockable rhythm in-hospital, around 70% had ST segment elevation, and about half received extracorporeal membrane oxygenation. The proportions of patients with 30-day favorable neurological outcomes were 36.6% (135) in the normothermic group and 36.6% (310) in the hypothermic group. No difference in neurological outcomes was observed in the multivariable regression analysis (adjusted OR 1.14, 95% CI 0.84-1.54), and the result was consistent in the IPW analysis (OR 1.11, 95% CI 0.84-1.47). Other outcomes also showed no significant differences.

CONCLUSION

In this nationwide, retrospective study using the JAAM-OHCA registry, we found no significant differences in 30-day favorable neurological outcome, 30-day survival, and adverse event incidences between hypothermic TTM (32-34°C) and normothermic TTM (35-36°C) in adult patients with OHCA due to ACS.

Mild therapeutic hypothermic protection activates the PI3K/AKT signaling pathway to inhibit TRPM7 and suppress ferroptosis induced by myocardial ischemia‑reperfusion injury

The present study aimed to investigate the role of PI3K‑mediated ferroptosis signaling induced by mild therapeutic hypothermia (MTH), which was defined as a temperature of 34˚C, in protecting against myocardial ischemia-reperfusion (I/R) injury (MIRI). To meet this aim, H9C2 cells underwent hypoxia‑reperfusion (H/R) and/or MTH. The MTT assay was used to assess cell viability, cytotoxicity was measured using a lactate dehydrogenase cytotoxicity assay, and Annexin V‑FITC/PI flow cytometric analysis was used to analyze early and late cell apoptosis. In addition, 84 healthy adult male Sprague‑Dawley rats were randomly divided into seven groups (n=12), and underwent I/R and various treatments. Hemodynamics were monitored, and the levels of myocardial injury marker enzymes and oxidative stress markers in myocardial tissue were measured using ELISA. The expression levels of PI3K, AKT, transient receptor potential cation channel subfamily M member 7 (TRPM7), glutathione peroxidase 4 (GPX4) and acyl‑CoA synthetase long chain family member 4 (ACSL4) in animals and cells were measured using western blot analysis. These experiments revealed that MTH could effectively reduce myocardial infarct size, improve hemodynamic performance following MIRI and suppress myocardial apoptosis, thereby contributing to the recovery from H/R injury. Mechanistically, MTH was revealed to be able to activate the PI3K/AKT signaling pathway in cells, upregulating GPX4, and downregulating the expression levels of TRPM7 and ACSL4. Treatment with 2‑aminoethoxydiphenyl borate (an inhibitor of TRPM7) could further strengthen the myocardial protective effects of MTH, whereas treatment with erastin (promoter of ferroptosis) and wortmannin (inhibitor of PI3K) led to the effective elimination of the myocardial protective effects of MTH. Compared with in the I/R group, the PI3K/AKT activation level and the expression levels of GPX4 were both significantly increased, whereas the expression levels of TRPM7 and ACSL4 were significantly decreased in the I/R + MTH group. Taken together, the results of the present study indicated that MTH may activate the PI3K/AKT signaling pathway to inhibit TRPM7 and suppress ferroptosis induced by MIRI.

Cardiogenic shock

Cardiogenic shock is a complex syndrome defined by systemic hypoperfusion and inadequate cardiac output arising from a wide array of underlying causes. Although the understanding of cardiogenic shock epidemiology, specific subphenotypes, haemodynamics, and cardiogenic shock severity staging has evolved, few therapeutic interventions have shown survival benefit. Results from seminal randomised controlled trials support early revascularisation of the culprit vessel in infarct-related cardiogenic shock and provide evidence of improved survival with the use of temporary circulatory support in selected patients. However, numerous questions remain unanswered, including optimal pharmacotherapy regimens, the role of mechanical circulatory support devices, management of secondary organ dysfunction, and best supportive care. This Review summarises current definitions, pathophysiological principles, and management approaches in cardiogenic shock, and highlights key knowledge gaps to advance individualised shock therapy and the evidence-based ethical use of modern technology and resources in cardiogenic shock.

Novel Long Noncoding RNA HEAT4 Affects Monocyte Subtypes, Reducing Inflammation and Promoting Vascular Healing

BACKGROUND

Activation of the immune system contributes to cardiovascular diseases. The role of human-specific long noncoding RNAs in cardioimmunology is poorly understood.

METHODS

Single-cell sequencing in peripheral blood mononuclear cells revealed a novel human-specific long noncoding RNA called HEAT4 (heart failure-associated transcript 4). HEAT4 expression was assessed in several in vitro and ex vivo models of immune cell activation, as well as in the blood of patients with heart failure (HF), acute myocardial infarction, or cardiogenic shock. The transcriptional regulation of HEAT4 was verified through cytokine treatment and single-cell sequencing. Loss-of-function and gain-of-function studies and multiple RNA-protein interaction assays uncovered a mechanistic role of HEAT4 in the monocyte anti-inflammatory gene program. HEAT4 expression and function was characterized in a vascular injury model in NOD.CB17-Prkdc scid/Rj mice.

RESULTS

HEAT4 expression was increased in the blood of patients with HF, acute myocardial infarction, or cardiogenic shock. HEAT4 levels distinguished patients with HF from people without HF and predicted all-cause mortality in a cohort of patients with HF over 7 years of follow-up. Monocytes, particularly anti-inflammatory CD16+ monocytes, which are increased in patients with HF, are the primary source of HEAT4 expression in the blood. HEAT4 is transcriptionally activated by treatment with anti-inflammatory interleukin-10. HEAT4 activates anti-inflammatory and inhibits proinflammatory gene expression. Increased HEAT4 levels result in a shift toward more CD16+ monocytes. HEAT4 binds to S100A9, causing a monocyte subtype switch, thereby reducing inflammation. As a result, HEAT4 improves endothelial barrier integrity during inflammation and promotes vascular healing after injury in mice.

CONCLUSIONS

These results characterize a novel endogenous anti-inflammatory pathway that involves the conversion of monocyte subtypes into anti-inflammatory CD16+ monocytes. The data identify a novel function for the class of long noncoding RNAs by preventing protein secretion and suggest long noncoding RNAs as potential targets for interventions in the field of cardioimmunology.

Efficacy and Safety of Therapeutic Hypothermia as an Adjuvant Therapy for Percutaneous Coronary Intervention in Acute Myocardial Infarction: A Systematic Review and Meta-Analysis

The study aims to compare the use of hypothermia in patients with myocardial infarction (MI) undergoing percutaneous coronary intervention (PCI) with control. We systematically searched four electronic databases until March 2022. The inclusion criteria were any study design that compared hypothermia in patients with MI undergoing PCI with control. The risk of bias assessment of the included randomized controlled trials was conducted through Cochrane Tool, while the quality of the included cohort studies was assessed by the NIH tool. The meta-analysis was performed on RevMan. A total of 19 studies were entered. Regarding the mortality, there were nonsignificant differences between hypothermia and control (odds ratio [OR] = 1.06, 95% confidence interval [CI] 0.75 to 1.50, p = 0.73). There was also no significant difference between the control and hypothermia in recurrent MI (OR = 1.21, 95% CI 0.64 to 2.30, p = 0.56). On the other hand, the analysis showed a significant favor for hypothermia over the control infarct size (mean difference = -1.76, 95% CI -3.04 to -0.47, p = 0.007), but a significant favor for the control over hypothermia in the overall bleeding complications (OR = 1.88, 95% CI 1.11 to 3.18, p = 0.02). Compared with the control, hypothermia reduced the infarct size of the heart, but this finding was not consistent across studies. However, the control had lower rates of bleeding problems. The other outcomes, such as death and the incidence of recurrent MI, were similar between the two groups.

Cardiogenic Shock Intravascular Cooling Trial (CHILL-SHOCK)

BACKGROUND

Cardiogenic shock (CS) is complicated by high mortality rates. Targeted temperature control (TTC) has been proposed as an adjunct therapy in CS. This study aims to examine the safety of TTC in patients presenting with CS.

METHODS AND RESULTS

In this open-label, randomized controlled pilot trial, 20 patients with hemodynamic criteria for CS were assigned to standard of care plus TTC vs standard of care alone. The primary outcome was a composite safety outcome, including well-described complications of TTC. Secondary outcomes included mortality at 90 days, invasive hemodynamic and echocardiographic parameters, electrocardiographic measurements, and inotrope dosing. There were no significant differences in the composite analysis of prespecified safety outcomes (3 events in the TTC group vs 0 events in the control group; P = 0.24). Patients randomized to TTC demonstrated a statistically significant increase in cardiac index and cardiac power index compared to the control group at 48-96 hours after randomization (3.6 [3.1, 3.9] L/min/m2 vs 2.6 [2.5, 3.15] L/min/m2; P = 0.029 and 0.61 [0.55, 0.7] W/m2 vs 0.53 [0.435, 0.565] W/m2; P = 0.029, respectively).

CONCLUSION

TTC may be a safe adjunct therapy for patients presenting with CS and may yield improvement in specific hemodynamic parameters.

Use of the Win Ratio Analysis in Critical Care Trials

Composite outcomes are commonly used in critical care trials to estimate the treatment effect of an intervention. A significant limitation of classical analytic approaches is that they assign equal statistical importance to each component in a composite, even if these do not have the same clinical importance (i.e., in a composite of death and organ failure, death is clearly more important). The win ratio (WR) method has been proposed as an alternative for trial outcomes evaluation, as it effectively assesses events based on their clinical relevance (i.e., hierarchical order) by comparing each patient in the intervention group with their counterparts in the control group. This statistical approach is increasingly used in cardiovascular outcome trials. However, WR may be useful to unveil treatment effects also in the critical care setting, because these trials are typically moderately sized, thus limiting the statistical power to detect small differences between groups, and often rely on composite outcomes that include several components of different clinical importance. Notably, the advantages of this approach may be offset by several drawbacks (such as ignoring ties and difficulties in selecting and ranking endpoints) and challenges in appropriate clinical interpretation (i.e., establishing clinical meaningfulness of the observed effect size). In this perspective article, we present some key elements to implementing WR statistics in critical care trials, providing an overview of strengths, drawbacks, and potential applications of this method. To illustrate, we conduct a reevaluation of the HYPO-ECMO (Hypothermia during Venoarterial Extracorporeal Membrane Oxygenation) trial using the WR framework as a case example.

Optimal Antithrombotic Strategies in Cardiogenic Shock

Cardiogenic shock (CS) represents a critical condition with a high mortality rate. The most common cause of CS is coronary artery disease, and patients typically present with myocardial infarction, necessitating immediate treatment through percutaneous coronary intervention (PCI) and often requiring mechanical circulatory support. CS is associated with a prothrombotic situation, while on the other hand, there is often a significant risk of bleeding. This dual challenge complicates the selection of an optimal antithrombotic strategy. The choice of antithrombotic agents must be personalized, taking into consideration all relevant conditions. Repeated risk assessment, therapeutic monitoring, and adjusting antithrombotic therapy are mandatory in these patients. This review article aims to provide an overview of the current evidence and practical guidance on antithrombotic strategies in the context of CS.

Hypothermia as an Adjunctive Therapy in Cardiogenic Shock: A Systematic Review and Meta-Analysis

In the setting of out-of-hospital cardiac arrest, therapeutic hypothermia (TH) has been shown to improve clinical outcomes. However, trials showing the advantage of TH did not include patients with cardiogenic shock (CS). We performed a comprehensive literature search for studies that evaluated the efficacy and safety of adjunctive TH compared with the standard of care (SOC) in patients with CS. The primary outcome was the mortality rate (in-hospital, short-, and mid-term). The secondary outcomes were the TH-related complications, duration of Intensive Care Unit (ICU) stay, duration of mechanical ventilation (MV-days), and improvement in cardiac function. Relative risk (RR) or the standardized mean difference (SMD) and corresponding 95% confidence intervals (CIs) were calculated using the random-effects model. A total of 7 clinical studies (3 RCTs included), and 712 patients (341 in the TH group and 371 in the SOC group) were included. As compared with the SOC, TH was not associated with a statistically significant improvement in the in-hospital (RR: 0.73%, 95% CI: 0.51-1.03; p = 0.08), short-term (RR: 0.90%, 95% CI: 0.75-1.06; p = 0.21), or mid-term (RR: 0.93%, 95% CI: 0.78-1.10; p = 0.38) mortality rates. Despite the improvement in the cardiac function in the TH group (SMD: 1.08, 95% CI: 0.02-2.1; p = 0.04), the TH strategy did not significantly shorten the MV days, or the ICU stay (p-values >0.05). Finally, there was a trend toward higher risks for infection, major bleeding, and the need for blood transfusion in the TH group. According to our meta-analysis of published clinical studies, TH is not beneficial in patients with CS and has a marginal safety profile. Larger-scale RCTs are needed to further clarify our results.

Health position paper and redox perspectives on reactive oxygen species as signals and targets of cardioprotection

The present review summarizes the beneficial and detrimental roles of reactive oxygen species in myocardial ischemia/reperfusion injury and cardioprotection. In the first part, the continued need for cardioprotection beyond that by rapid reperfusion of acute myocardial infarction is emphasized. Then, pathomechanisms of myocardial ischemia/reperfusion to the myocardium and the coronary circulation and the different modes of cell death in myocardial infarction are characterized. Different mechanical and pharmacological interventions to protect the ischemic/reperfused myocardium in elective percutaneous coronary interventions and coronary artery bypass grafting, in acute myocardial infarction and in cardiotoxicity from cancer therapy are detailed. The second part keeps the focus on ROS providing a comprehensive overview of molecular and cellular mechanisms involved in ischemia/reperfusion injury. Starting from mitochondria as the main sources and targets of ROS in ischemic/reperfused myocardium, a complex network of cellular and extracellular processes is discussed, including relationships with Ca2+ homeostasis, thiol group redox balance, hydrogen sulfide modulation, cross-talk with NAPDH oxidases, exosomes, cytokines and growth factors. While mechanistic insights are needed to improve our current therapeutic approaches, advancements in knowledge of ROS-mediated processes indicate that detrimental facets of oxidative stress are opposed by ROS requirement for physiological and protective reactions. This inevitable contrast is likely to underlie unsuccessful clinical trials and limits the development of novel cardioprotective interventions simply based upon ROS removal.

Distribution and 24-hour transition of SCAI shock stages and their association with 30-day mortality in acute myocardial infarction

The Society for Cardiovascular Angiography and Interventions (SCAI) shock classification has been shown to predict mortality in acute myocardial infarction (AMI). However, data on the transition of SCAI stages and their association with mortality after AMI are limited. All patients with AMI admitted to Vietnam National Heart Institute between August 2022 and February 2023 were classified into SCAI stages A, B, and C/D/E at admission and were reevaluated in 24 hours. We used Kaplan-Meier estimate and multivariable Cox regression analysis to assess the association between SCAI stages transition and 30-day mortality. We included 139 patients (median age 69 years, 29.5% female). On admission, 50.4%, 20.1%, and 29.5% of patients were classified as SCAI stage A, B, and C/D/E, respectively. The proportion of patients whose SCAI stage improved, remained stable, or worsened after 24 hours was 14.4%, 66.2%, and 19.4%, respectively. The 30-day mortality in patients with initial SCAI stages A, B, and C/D/E on admission was 2.9%, 21.4%, and 61.0%, respectively (P < .001). The 30-day mortality was 2.4% for patients with baseline SCAI stage A/B who remained unchanged or improved, 30.0% for patients with baseline SCAI stage C/D/E who remained unchanged or improved, and 92.6% for patients with SCAI stage B/C/D/E who worsened at 24 hours after admission (log-rank P < .001). In patients with AMI, evaluating the SCAI stage shock stage on admission and reevaluating after 24 hours added more information about 30-day mortality.

Organ dysfunction, injury, and failure in cardiogenic shock

BACKGROUND

Cardiogenic shock (CS) is caused by primary cardiac dysfunction and induced by various and heterogeneous diseases (e.g., acute impairment of cardiac performance, or acute or chronic impairment of cardiac performance).

MAIN BODY

Although a low cardiac index is a common finding in patients with CS, the ventricular preload, pulmonary capillary wedge pressure, central venous pressure, and systemic vascular resistance might vary between patients. Organ dysfunction has traditionally been attributed to the hypoperfusion of the organ due to either progressive impairment of the cardiac output or intravascular volume depletion secondary to CS. However, research attention has recently shifted from this cardiac output ("forward failure") to venous congestion ("backward failure") as the most important hemodynamic determinant. Both hypoperfusion and/or venous congestion by CS could lead to injury, impairment, and failure of target organs (i.e., heart, lungs, kidney, liver, intestines, brain); these effects are associated with an increased mortality rate. Treatment strategies for the prevention, reduction, and reversal of organ injury are warranted to improve morbidity in these patients. The present review summarizes recent data regarding organ dysfunction, injury, and failure.

CONCLUSIONS

Early identification and treatment of organ dysfunction, along with hemodynamic stabilization, are key components of the management of patients with CS.

Microcirculatory dysfunction in cardiogenic shock

Cardiogenic shock is usually defined as primary cardiac dysfunction with low cardiac output leading to critical organ hypoperfusion, and tissue hypoxia, resulting in high mortality rate between 40% and 50% despite recent advances. Many studies have now evidenced that cardiogenic shock not only involves systemic macrocirculation, such as blood pressure, left ventricular ejection fraction, or cardiac output, but also involves significant systemic microcirculatory abnormalities which seem strongly associated with the outcome. Although microcirculation has been widely studied in the context of septic shock showing heterogeneous alterations with clear evidence of macro and microcirculation uncoupling, there is now a growing body of literature focusing on cardiogenic shock states. Even if there is currently no consensus regarding the treatment of microcirculatory disturbances in cardiogenic shock, some treatments seem to show a benefit. Furthermore, a better understanding of the underlying pathophysiology may provide hypotheses for future studies aiming to improve cardiogenic shock prognosis.

The medical treatment of cardiogenic shock

Cardiogenic shock (CS) is a leading cause of mortality worldwide. CS presentation and management in the current era have been widely depicted in epidemiological studies. Its treatment is codified and relies on medical care and extracorporeal life support (ECLS) in the bridge to recovery, chronic mechanical device therapy, or transplantation. Recent improvements have changed the landscape of CS. The present analysis aims to review current medical treatments of CS in light of recent literature, including addressing excitation-contraction coupling and specific physiology on applied hemodynamics. Inotropism, vasopressor use, and immunomodulation are discussed as pre-clinical and clinical studies have focused on new therapeutic options to improve patient outcomes. Certain underlying conditions of CS, such as hypertrophic or Takotsubo cardiomyopathy, warrant specifically tailored management that will be overviewed in this review.

Influence of Culprit Lesion Intervention on Outcomes in Infarct-Related Cardiogenic Shock With Cardiac Arrest

BACKGROUND

Cardiac arrest (CA) is common in patients with infarct-related cardiogenic shock (CS).

OBJECTIVES

The goal of this study was to identify the characteristics and outcomes of culprit lesion percutaneous coronary intervention (PCI) of patients with infarct-related CS stratified according to CA in the CULPRIT-SHOCK (Culprit Lesion Only PCI Versus Multivessel PCI in Cardiogenic Shock) randomized trial and registry.

METHODS

Patients with CS with and without CA from the CULPRIT-SHOCK study were analyzed. All-cause death or severe renal failure leading to renal replacement therapy within 30 days and 1-year death were assessed.

RESULTS

Among 1,015 patients, 550 (54.2%) had CA. Patients with CA were younger, more frequently male, had lower rates of peripheral artery disease, a glomerular filtration rate <30 mL/min, and left main disease, and they presented more often with clinical signs of impaired organ perfusion. The composite of all-cause death or severe renal failure within 30 days occurred in 51.2% of patients with CA vs 48.5% in non-CA patients (P = 0.39) and 1-year death in 53.8% vs 50.4% (P = 0.29), respectively. In a multivariate analysis, CA was an independent predictor of 1-year mortality (HR: 1.27; 95% CI: 1.01-1.59). In the randomized trial, culprit lesion-only PCI was superior to immediate multivessel PCI in patients both with and without CA (P for interaction = 0.6).

CONCLUSIONS

More than 50% of patients with infarct-related CS had CA. These patients with CA were younger and had fewer comorbidities, but CA was an independent predictor of 1-year mortality. Culprit lesion-only PCI is the preferred strategy, both in patients with and without CA. (Culprit Lesion Only PCI Versus Multivessel PCI in Cardiogenic Shock [CULPRIT-SHOCK]; NCT01927549).

Contemporary Management of Cardiogenic Shock Complicating Acute Myocardial Infarction

Despite an improvement in pharmacological therapies and mechanical reperfusion, the outcome of patients with acute myocardial infarction (AMI) is still suboptimal, especially in patients with cardiogenic shock (CS). The incidence of CS accounts for 3-15% of AMI cases, with mortality rates of 40% to 50%. In contrast to a large number of trials conducted in patients with AMI without CS, there is limited evidence-based scientific knowledge in the CS setting. Therefore, recommendations and actual treatments are often based on registry data. Similarly, knowledge of the available options in terms of temporary mechanical circulatory support (MCS) devices is not equally widespread, leading to an underutilisation or even overutilisation in different regions/countries of these treatment options and nonuniformity in the management of CS. The aim of this article is to provide a critical overview of the available literature on the management of CS as a complication of AMI, summarising the most recent evidence on revascularisation strategies, pharmacological treatments and MCS use.

Therapeutic Hypothermia Inhibits Hypoxia-Induced Cardiomyocyte Apoptosis Via the MiR-483-3p/Cdk9 Axis

Background Therapeutic hypothermia has a beneficial effect on cardiac function after acute myocardial infarction, but the exact mechanism is still unclear. Recent research has suggested that microRNAs participate in acute myocardial infarction to regulate cardiomyocyte survival. This study aimed to explore the ability of hypothermia-regulated microRNA-483-3p (miR-483-3p) to inhibit hypoxia-induced myocardial infarction. Methods and Results Primary cardiomyocytes were cultured under hypoxia at 32 °C to mimic therapeutic hypothermia, and the differentially expressed microRNAs were determined by RNA sequencing. Therapeutic hypothermia recovered hypoxia-induced increases in apoptosis, decreases in ATP levels, and decreases in miR-483-3p expression. Overexpression of miR-483-3p exhibited effects similar to those of therapeutic hypothermia on hypoxia in the treatment of cardiomyocytes to associate with maintaining the mitochondrial membrane potential, and cyclin-dependent kinase 9 (Cdk9) was identified as a target gene with downregulated expression by miR-483-3p. Knockdown of Cdk9 also promoted cardiac survival, ATP production, and mitochondrial membrane potential stability under hypoxia. In vivo, the expression of miR-483-3p and Cdk9 was tested in the cardiac tissue of the mice with acute myocardial infarction, and the expression of miR-483-3p decreased and Cdk9 increased in the region of myocardial infarction. However, miR-483-3p was overexpressed with lentivirus, which suppressed apoptosis, infarct size (miR-483-3p, 22.00±4.04% versus negative control, 28.57±5.44%, P<0.05), and Cdk9 expression to improve cardiac contractility. Conclusions MiR-483-3p antagonizes hypoxia, leading to cardiomyocyte injury by targeting Cdk9, which is a new mechanism of therapeutic hypothermia.

Circulating Galectin-3 in Patients with Cardiogenic Shock Complicating Acute Myocardial Infarction Treated with Mild Hypothermia: A Biomarker Sub-Study of the SHOCK-COOL Trial

Background: Galectin-3 (Gal-3) is considered a potential cardiovascular inflammatory marker that may provide additional risk stratification for patients with acute heart failure. It is unknown whether mild therapeutic hypothermia (MTH) impacts Gal-3 levels. Therefore, this biomarker study aimed to investigate the effect of MTH on Gal-3. Methods: In the randomized SHOCK-COOL trial, 40 patients with cardiogenic shock (CS) complicating acute myocardial infraction (AMI) were randomly assigned to the MTH (33 °C) or control group in a 1:1 ratio. Blood samples were collected on the day of admission/day 1, day 2, and day 3. Gal-3 level kinetics throughout these time points were compared between the MTH and control groups. Additionally, potential correlations between Gal-3 and clinical patient characteristics were assessed. Multiple imputations were performed to account for missing data. Results: In the control group, Gal-3 levels were significantly lower on day 3 than on day 1 (day 1 vs. day 3: 3.84 [IQR 2.04−13.3] vs. 1.79 [IQR 1.23−3.50] ng/mL; p = 0.049). Gal-3 levels were not significantly different on any day between the MTH and control groups (p for interaction = 0.242). Spearman’s rank correlation test showed no significant correlation between Gal-3 levels and sex, age, smoking, body mass index (BMI), and levels of creatine kinase-MB, creatine kinase, C-reactive protein, creatinine, and white blood cell counts (all p > 0.05). Patients with lower Gal-3 levels on the first day after admission demonstrated a higher risk of all-cause mortality at 30 days (hazard ratio, 2.67; 95% CI, 1.11−6.42; p = 0.029). In addition, Gal-3 levels on day 1 had a good predictive value for 30-day all-cause mortality with an area under the receiver operating characteristic curve of 0.696 (95% CI: 0.513−0.879), with an optimal cut-off point of less than 3651 pg/mL. Conclusions: MTH has no effect on Gal-3 levels in patients with CS complicating AMI compared to the control group. In addition, Gal-3 is a relatively stable biomarker, independent of age, sex, and BMI, and Gal-3 levels at admission might predict the risk of 30-day all-cause mortality.

Contemporary Management of Concomitant Cardiac Arrest and Cardiogenic Shock Complicating Myocardial Infarction

Cardiogenic shock (CS) and cardiac arrest (CA) are the most life-threatening complications of acute myocardial infarction. Although there is a significant overlap in the pathophysiology with approximately half the patients with CS experiencing a CA and approximately two-thirds of patients with CA developing CS, comprehensive guideline recommendations for management of CA + CS are lacking. This paper summarizes the current evidence on the incidence, pathophysiology, and short- and long-term outcomes of patients with acute myocardial infarction complicated by concomitant CA + CS. We discuss the hemodynamic factors and unique challenges that need to be accounted for while developing treatment strategies for these patients. A summary of expert-based step-by-step recommendations to the approach and treatment of these patients, both in the field before admission and in-hospital management, are presented.

Circulating Monocyte Chemoattractant Protein-1 in Patients with Cardiogenic Shock Complicating Acute Myocardial Infarction Treated with Mild Hypothermia: A Biomarker Substudy of SHOCK-COOL Trial

Background: There is evidence that monocyte chemoattractant protein-1 (MCP-1) levels reflect the intensity of the inflammatory response in patients with cardiogenic shock (CS) complicating acute myocardial infarction (AMI) and have a predictive value for clinical outcomes. However, little is known about the effect of mild therapeutic hypothermia (MTH) on the inflammatory response in patients with CS complicating AMI. Therefore, we conducted a biomarker study to investigate the effect of MTH on MCP-1 levels in patients with CS complicating AMI. Methods: In the randomized mild hypothermia in cardiogenic shock (SHOCK-COOL) trial, 40 patients with CS complicating AMI were enrolled and assigned to MTH (33 °C) for 24 h or normothermia at a 1:1 ratio. Blood samples were collected at predefined time points at the day of admission/day 1, day 2 and day 3. Differences in MCP-1 levels between and within the MTH and normothermia groups were assessed. Additionally, the association of MCP-1 levels with the risk of all-cause mortality at 30 days was analyzed. Missing data were accounted for by multiple imputation as sensitivity analyses. Results: There were differences in MCP-1 levels over time between patients in MTH and normothermia groups (P for interaction = 0.013). MCP-1 levels on day 3 were higher than on day 1 in the MTH group (day 1 vs day 3: 21.2 [interquartile range, 0.25–79.9] vs. 125.7 [interquartile range, 87.3–165.4] pg/mL; p = 0.006) and higher than in the normothermia group at day 3 (MTH 125.7 [interquartile range, 87.3–165.4] vs. normothermia 12.3 [interquartile range, 0–63.9] pg/mL; p = 0.011). Irrespective of therapy, patients with higher levels of MCP-1 at hospitalization tended to have a decreased risk of all-cause mortality at 30 days (HR, 2.61; 95% CI 0.997–6.83; p = 0.051). Conclusions: The cooling phase of MTH had no significant effect on MCP-1 levels in patients with CS complicating AMI compared to normothermic control, whereas MCP-1 levels significantly increased after rewarming. Trial registration: NCT01890317.

Basic mechanisms in cardiogenic shock: part 2 - biomarkers and treatment options

Cardiogenic shock mortality rates remain high despite significant advances in cardiovascular medicine and the widespread uptake of mechanical circulatory support systems. Except for early invasive angiography and percutaneous coronary intervention of the infarct-related artery, all other widely used therapeutic measures are based on low-quality evidence. The grim prognosis and lack of high-quality data warrant further action. Within Part 2 of this two-part educational review on basic mechanisms in cardiogenic shock, we aimed to highlight the current status of translating our understanding of the pathophysiology of cardiogenic shock into clinical practice. We summarize the current status of biomarker research in risk stratification and therapy guidance. In addition, we summarized the current status of translating the findings from bench-, bedside, and biomarker studies into treatment options. Several large randomized controlled trials (RCTs) are underway, providing a huge opportunity to study contemporary cardiogenic shock patients. Finally, we call for translational, homogenous, biomarker-based, international RCTs testing novel treatment approaches to improve the outcome of our patients.

Comparative Analysis of Patient Characteristics in Cardiogenic Shock Studies: Differences Between Trials and Registries

OBJECTIVES

This study sought to evaluate the differences in cardiogenic shock patient characteristics in trial patients and real-life patients.

BACKGROUND

Cardiogenic shock (CS) is a leading cause of mortality in patients presenting with acute myocardial infarction (AMI). However, the enrollment of patients into clinical trials is challenging and may not be representative of real-world patients.

METHODS

We performed a systematic review of studies in patients presenting with AMI-related CS and compared patient characteristics of those enrolled into randomized controlled trials (RCTs) with those in registries.

RESULTS

We included 14 RCTs (n = 2,154) and 12 registries (n = 133,617). RCTs included more men (73% vs 67.7%, P < 0.001) compared with registries. Patients enrolled in RCTs had fewer comorbidities, including less hypertension (61.6% vs 65.9%, P < 0.001), dyslipidemia (36.4% vs 53.6%, P < 0.001), a history of stroke or transient ischemic attack (7.1% vs 10.7%, P < 0.001), and prior coronary artery bypass graft surgery (5.4% vs 7.5%, P < 0.001). Patients enrolled in RCTs also had lower lactate levels (4.7 ± 2.3 mmol/L vs 5.9 ± 1.9 mmol/L, P < 0.001) and higher mean arterial pressure (73.0 ± 8.8 mm Hg vs 62.5 ± 12.2 mm Hg, P < 0.001). Percutaneous coronary intervention (97.5% vs 58.4%, P < 0.001) and extracorporeal membrane oxygenation (11.6% vs 3.4%, P < 0.001) were used more often in RCTs. The in-hospital mortality (23.9% vs 38.4%, P < 0.001) and 30-day mortality (39.9% vs 45.9%, P < 0.001) were lower in RCT patients.

CONCLUSIONS

RCTs in AMI-related CS tend to enroll fewer women and lower-risk patients compared with registries. Patients enrolled in RCTs are more likely to receive aggressive treatment with percutaneous coronary intervention and extracorporeal membrane oxygenation and have lower in-hospital and 30-day mortality.

Cardiogenic Shock Management and Research: Past, Present, and Future Outlook

Although great strides have been made in the pathophysiological understanding, diagnosis and management of cardiogenic shock (CS), morbidity and mortality in patients presenting with the condition remain high. Acute MI is the commonest cause of CS; consequently, most existing literature concerns MI-associated CS. However, there are many more phenotypes of patients with acute heart failure. Medical treatment and mechanical circulatory support are well-established therapeutic options, but evidence for many current treatment regimens is limited. The issue is further complicated by the fact that implementing adequately powered, randomized controlled trials are challenging for many reasons. In this review, the authors discuss the history, landmark trials, current topics of medical therapy and mechanical circulatory support regimens, and future perspectives of CS management.

Effect of Moderate Hypothermia vs Normothermia on 30-Day Mortality in Patients With Cardiogenic Shock Receiving Venoarterial Extracorporeal Membrane Oxygenation: A Randomized Clinical Trial

IMPORTANCE

The optimal approach to the use of venoarterial extracorporeal membrane oxygenation (ECMO) during cardiogenic shock is uncertain.

OBJECTIVE

To determine whether early use of moderate hypothermia (33-34 °C) compared with strict normothermia (36-37 °C) improves mortality in patients with cardiogenic shock receiving venoarterial ECMO.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial of patients (who were eligible if they had been endotracheally intubated and were receiving venoarterial ECMO for cardiogenic shock for <6 hours) conducted in the intensive care units at 20 French cardiac shock care centers between October 2016 and July 2019. Of 786 eligible patients, 374 were randomized. Final follow-up occurred in November 2019.

INTERVENTIONS

Early moderate hypothermia (33-34 °C; n = 168) for 24 hours or strict normothermia (36-37 °C; n = 166).

MAIN OUTCOMES AND MEASURES

The primary outcome was mortality at 30 days. There were 31 secondary outcomes including mortality at days 7, 60, and 180; a composite outcome of death, heart transplant, escalation to left ventricular assist device implantation, or stroke at days 30, 60, and 180; and days without requiring a ventilator or kidney replacement therapy at days 30, 60, and 180. Adverse events included rates of severe bleeding, sepsis, and number of units of packed red blood cells transfused during venoarterial ECMO.

RESULTS

Among the 374 patients who were randomized, 334 completed the trial (mean age, 58 [SD, 12] years; 24% women) and were included in the primary analysis. At 30 days, 71 patients (42%) in the moderate hypothermia group had died vs 84 patients (51%) in the normothermia group (adjusted odds ratio, 0.71 [95% CI, 0.45 to 1.13], P = .15; risk difference, -8.3% [95% CI, -16.3% to -0.3%]). For the composite outcome of death, heart transplant, escalation to left ventricular assist device implantation, or stroke at day 30, the adjusted odds ratio was 0.61 (95% CI, 0.39 to 0.96; P = .03) for the moderate hypothermia group compared with the normothermia group and the risk difference was -11.5% (95% CI, -23.2% to 0.2%). Of the 31 secondary outcomes, 30 were inconclusive. The incidence of moderate or severe bleeding was 41% in the moderate hypothermia group vs 42% in the normothermia group. The incidence of infections was 52% in both groups. The incidence of bacteremia was 20% in the moderate hypothermia group vs 30% in the normothermia group.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial involving patients with refractory cardiogenic shock treated with venoarterial ECMO, early application of moderate hypothermia for 24 hours did not significantly increase survival compared with normothermia. However, because the 95% CI was wide and included a potentially important effect size, these findings should be considered inconclusive.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02754193.

Management of cardiogenic shock

Despite the rapidly evolving evidence base in modern cardiology, progress in the area of cardiogenic shock remains slow, with short-term mortality still reaching 40-50%, relatively unchanged in recent years. Despite advances with an increase in the number of clinical trials taking place in this admittedly difficult-to-study area, the evidence base on which we make day-to-day decisions in clinical practice remains relatively sparse. With only definitive evidence for early revascularisation and the relative ineffectiveness of intra-aortic balloon pumping, most aspects of patient management are based on expert consensus, rather than randomised controlled trials. This updated 2020 review will outline the management of CS mainly after acute myocardial infarction with major focus on state-of-the-art treatment based on randomised clinical trials or matched comparisons if available.

Mild Hypothermia Therapy Lowers the Inflammatory Level and Apoptosis Rate of Myocardial Cells of Rats with Myocardial Ischemia-Reperfusion Injury via the NLRP3 Inflammasome Pathway

Objective

To explore the protective effects and mechanism of mild hypothermia treatment in the treatment of myocardial ischemia-reperfusion injury. Material and Methods. A total of 20 Sprague-Dawley (SD) rats were assigned to 4 groups: the blank control group, sham operation group, ischemia reperfusion group, and mild hypothermia therapy group (each n = 5). Some indexes were detected. In addition, myocardial cell models of oxygen-glucose deprivation/reoxygenation injury (OGD) were established. The expression of mRNA IL-6 and TNF-α and the key enzyme levels of apoptosis (cleaved-Caspase-3) and the NLRP3 inflammasome/p53 signaling pathway in the models were determined.

Results

The expression of serum IL-6 and TNF-α in the mild hypothermia therapy group was significantly lower than that in the ischemia reperfusion group. The mild hypothermia therapy group also showed a significantly lower TUNEL cell count and NLRP3 and p53 phosphorylation levels than the ischemia reperfusion group (all p < 0.05). The in vitro mild hypothermia + OGD group also showed significantly lower mRNA expression of IL-6 and TNF-α and levels of cleaved Caspase-3, NLRP3, and phosphorylated p53 protein than the OGD group (all p < 0.05).

Conclusion

In conclusion, mild hypothermia therapy can inhibit the apoptosis and myocardial inflammation of cells induced by MI/R injury in rats and inhibiting the activity of the NLRP3 inflammasome pathway and p53 signaling pathway may be the mechanism.

Vasopressor-Sparing Strategies in Patients with Shock: A Scoping-Review and an Evidence-Based Strategy Proposition

Despite the abundant literature on vasopressor therapy, few studies have focused on vasopressor-sparing strategies in patients with shock. We performed a scoping-review of the published studies evaluating vasopressor-sparing strategies by analyzing the results from randomized controlled trials conducted in patients with shock, with a focus on vasopressor doses and/or duration reduction. We analyzed 143 studies, mainly performed in septic shock. Our analysis demonstrated that several pharmacological and non-pharmacological strategies are associated with a decrease in the duration of vasopressor therapy. These strategies are as follows: implementing a weaning strategy, vasopressin use, systemic glucocorticoid administration, beta-blockers, and normothermia. On the contrary, early goal directed therapies, including fluid therapy, oral vasopressors, vitamin C, and renal replacement therapy, are not associated with an increase in vasopressor-free days. Based on these results, we proposed an evidence-based vasopressor management strategy.

Hypothermia for Reduction of Myocardial Reperfusion Injury in Acute Myocardial Infarction: Closing the Translational Gap

Myocardial reperfusion injury-triggered by an inevitable inflammatory response after reperfusion-may undo a considerable part of the myocardial salvage achieved through timely percutaneous coronary intervention in patients with acute myocardial infarction. Because infarct size is strongly correlated to mortality and risk of heart failure, the importance of endeavors for cardioprotective therapies to attenuate myocardial reperfusion injury and decrease infarct size remains undisputed. Myocardial reperfusion injury is the result of several complex nonlinear phenomena, and for a therapy to be effective, it should act on multiple targets involved in this injury. In this regard, hypothermia remains a promising treatment despite a number of negative randomized controlled trials in humans with acute myocardial infarction so far. To turn the tide for hypothermia in patients with acute myocardial infarction, sophisticated solutions for important limitations of systemic hypothermia should continue to be developed. In this review, we provide a comprehensive overview of the pathophysiology and clinical expression of myocardial reperfusion injury and discuss the current status and possible future of hypothermia for cardioprotection in patients with acute myocardial infarction.

Variability in reporting of key outcome predictors in acute myocardial infarction cardiogenic shock trials

BACKGROUND

Among acute myocardial infarction patients with cardiogenic shock (AMICS), a number of key variables predict mortality, including cardiac arrest (CA) and shock classification as proposed by Society for Cardiovascular Angiography and Intervention (SCAI). Given this prognostic importance, we examined the frequency of reporting of high risk variables in published randomized controlled trials (RCTs) of AMICS patients.

METHODS

We identified 15 RCTs enrolling 2,500 AMICS patients and then reviewed rates of CA, baseline neurologic status, right heart catheterization data, lactate levels, inotrope and vasopressor requirement, hypothermia, mechanical ventilation, left ventricular ejection fraction (LVEF), mechanical circulatory support, and specific cause of death based on the primary manuscript and Data in S1.

RESULTS

A total of 2,500 AMICS patients have been enrolled in 15 clinical trials over 21 years with only four trials enrolling >80 patients. The reporting frequency and range for key prognostic factors was: neurologic status (0% reported), hypothermia (28% reported, prevalence 33-75%), specific cause of death (33% reported), cardiac index and wedge pressure (47% reported, range 1.6-2.3 L min^-1 m^-2 and 15-24 mmHg), lactate (60% reported, range 4-7.7 mmol/L), LVEF (73% reported, range 25-45%), CA (80% reported, prevalence 0-92%), MCS (80% reported, prevalence 13-100%), and mechanical ventilation (93% reported, prevalence 35-100%). This variability was reflected in the 30-day mortality which ranged from 20-73%.

CONCLUSIONS

In a comprehensive review of seminal RCTs in AMICS, important predictors of outcome were frequently not reported. Future efforts to standardize CS trial data collection and reporting may allow for better assessment of novel therapies for AMICS.

Study of risk factors for intraoperative hypothermia during pediatric burn surgery

Background

Intraoperative hypothermia (core temperature <36.0°C) is common during the perioperative period and can result in adverse consequences, especially in children. We aimed to determine the incidence of intraoperative hypothermia and its risk factors in pediatric patients during burn surgery.

Methods

In the present study we enrolled 197 pediatric patients with burn injury undergoing surgical debridement and skin grafting. Factors, such as total burn surface area (TBSA), were collected and analyzed to identify the potential risk factors for intraoperative hypothermia.

Results

The incidence of intraoperative hypothermia among all patients was 17.8%. Compared with patients with normothermia, children with hypothermia were associated with larger TBSA (25% vs 15%, p<0.001) and with less intraoperative active warming (34.28% vs 54.93%, p<0.05). In addition, compared with patients with moderate-degree burn, patients with severe and extremely severe burn were associated with much higher risk of intraoperative hypothermia [severe: odds ratio (OR)=3.805, 95% confidence interval (CI)=1.396-10.368, p=0.009; extremely severe: OR=6.933, 95% CI=2.604-18.462, p<0.001]. TBSA was the only independent risk factor that emerged as being strongly associated with intraoperative hypothermia (OR=1.068, p=0.001) and could be used to predict the occurrence of hypothermia when combined with other factors. TBSA for predicting intraoperative hypothermia by receiver operating characteristic (ROC) curve analysis showed a good predictive ability with an area under the ROC curve of 0.758.

Conclusion

TBSA is an important risk factor for intraoperative hypothermia in pediatric patients with burn.

Hemodynamic and metabolic recovery in acute myocardial infarction-related cardiogenic shock is more rapid among patients presenting with out-of-hospital cardiac arrest

Background

Most studies in acute myocardial infarction complicated by cardiogenic shock (AMICS) include patients presenting with and without out-of-hospital cardiac arrest (OHCA). The aim was to compare OHCA and non-OHCA AMICS patients in terms of hemodynamics, management in the intensive care unit (ICU) and outcome.

Methods

From a cohort corresponding to two thirds of the Danish population, all patients with AMICS admitted from 2010–2017 were individually identified through patient records.

Results

A total of 1716 AMICS patients were identified of which 723 (42%) presented with OHCA. A total of 1532 patients survived to ICU admission. At the time of ICU arrival, there were no differences between OHCA and non-OHCA AMICS patients in variables commonly used in the AMICS definition (mean arterial pressure (MAP) (72mmHg vs 70mmHg, p = 0.12), lactate (4.3mmol/L vs 4.0mmol/L, p = 0.09) and cardiac output (CO) (4.6L/min vs 4.4L/min, p = 0.30)) were observed. However, during the initial days of ICU treatment OHCA patients had a higher MAP despite a lower need for vasoactive drugs, higher CO, SVO2 and lactate clearance compared to non-OHCA patients (p<0.05 for all). In multivariable analysis outcome was similar but cause of death differed significantly with hypoxic brain injury being leading cause in OHCA and cardiac failure in non-OHCA AMICS patients.

Conclusion

OHCA and non-OHCA AMICS patients initially have comparable metabolic and hemodynamic profiles, but marked differences develop between the groups during the first days of ICU treatment. Thus, pooling of OHCA and non-OHCA patients as one clinical entity in studies should be done with caution.

Acute Myocardial Infarction Complicated by Cardiogenic Shock: Analysis of the Position Statement From the European Society of Cardiology Acute Cardiovascular Care Association, With Perioperative Implications

Effective management of cardiogenic shock (CS) is hampered by a lack of evidence-based information. This is a high-mortality condition, without clear, evidence-based guidelines for perioperative management, specifically-a lack of target endpoints for treatment (e.g.: mean arterial pressure or oxygenation), utility of regional care systems or the benefits of palliative care. The Acute Cardiovascular Care Association (ACCA) of the European Society of Cardiology (ESC) recently published a position statement that aimed to offer contemporary guidance on the diagnosis and treatment of acute myocardial infarction (AMI) complicated by CS. Herein, we review this complex clinical topic and review the ACCA statement on AMI associated with CS, with a focus on relevance to perioperative management.

2020 Focused Update of the 2012 Guidelines of the Taiwan Society of Cardiology for the Management of ST-Segment Elevation Myocardial Infarction

One of the major missions of the Taiwan Society of Cardiology is to publish practice guidelines that are suitable for local use in Taiwan. The ultimate purpose is to continuously improve cardiovascular health care from the implementation of the recommendations in the guidelines. Despite recent improvement of medical care, patients with ST-segment elevation myocardial infarction (STEMI) still carry a high morbidity and mortality. There have been many changes in the concepts of STEMI diagnosis and treatment in recent years. The 2020 focused update of the 2012 guidelines of the Taiwan Society of Cardiology for the management of STEMI is an amendment of the 2012 guidelines based on the newest published scientific data. The recommendations in this focused update provide the diagnosis and treatment strategy for STEMI that should be generally implemented in Taiwan. Nevertheless, guidelines never completely replace clinical judgment and medical decision still should be determined individually.

Hypothermia in patients with acute myocardial infarction: a meta-analysis of randomized trials

BACKGROUND

In patients with acute myocardial infarction (MI) receiving percutaneous coronary intervention (PCI), the role of systemic therapeutic hypothermia remains controversial. We sought to investigate the role of systemic therapeutic hypothermia versus standard of care in patients with acute MI treated with PCI.

METHODS

This is a study-level meta-analysis of randomized trials. The primary outcome was all-cause death. The main secondary outcome was infarct size. Other secondary outcomes were recurrent MI, ischemia-driven target vessel revascularization (TVR), major adverse cardiovascular events, and bleeding.

RESULTS

A total of 1012 patients with acute MI receiving a PCI in nine trials (503 randomly assigned to hypothermia and 509 to control) were available for the quantitative synthesis. The weighted median follow-up was 30 days. As compared to controls, patients assigned to hypothermia had similar risk of all-cause death (risk ratio, [95% confidence intervals], 1.25 [0.80; 1.95], p = 0.32), with a trend toward higher risk of ischemia-driven TVR (3.55 [0.80; 15.87], p = 0.09) mostly due to acute or subacute stent thrombosis. Although in the overall cohort, infarct size was comparable between groups (standardized mean difference [95% Confidence intervals], 0.06 [- 0.92; 1.04], p = 0.92), patients effectively achieving the protocol-defined target temperature in the hypothermia group had smaller infarct size as compared to controls (p for interaction = 0.016). Treatment strategies did not differ with respect to the other outcomes.

CONCLUSIONS

As compared to standard of care, systemic therapeutic hypothermia in acute MI patients treated with PCI provided similar mortality with a signal toward more frequent repeat revascularization. Among patients assigned to hypothermia, those effectively achieving the protocol-defined target temperature displayed smaller infarct size.

TRIAL REGISTRATION

PROSPERO, CRD42019138754.

Assessment of microcirculation in cardiogenic shock

PURPOSE OF REVIEW

Adequate tissue perfusion is of utmost importance to avoid organ failure in patients with cardiogenic shock. Within the recent years, the microcirculation, defined as the perfusion of the smallest vessels, has been identified to play a crucial role. Microcirculatory changes may include capillary flow disturbances as well as changes in the density of perfused vessels. Due to the availability of new technologies to assess the microcirculation, interesting new data came up and it is the purpose of this review to summarize recent studies in the field.

RECENT FINDINGS

Nowadays, an increasing number of studies confirm parameters of the microcirculation, derived by intravital microscopy, to represent strong outcome predictors in cardiogenic shock. In addition, microcirculation as read-out parameter in innovative clinical studies has meanwhile been accepted as serious endpoint. Treatment strategies such as mechanical assist devices, blood pressure regulating agents or fluids use tissue perfusion and microcirculatory network density as targets in addition to clinical perfusion evaluation and decreasing serum lactate levels.

SUMMARY

The parameter most frequently used to detect tissue malperfusion is serum lactate. Novel, noninvasive methods to quantify microvascular perfusion have the potential to guide treatment in terms of optimizing organ perfusion and oxygenation probably paving the way for an individualized therapy.

Acute Cardiovascular Care Association position statement for the diagnosis and treatment of patients with acute myocardial infarction complicated by cardiogenic shock: A document of the Acute Cardiovascular Care Association of the European Society of Cardiology

Most of the guideline-recommended treatment strategies for patients with acute coronary syndromes have been tested in large randomised clinical trials. Still, a major challenge is represented by patients with acute myocardial infarction admitted with impending or established cardiogenic shock. Despite early revascularization the mortality of cardiogenic shock remains high and roughly half of patients do not survive until hospital discharge or 30-day follow-up. However, there is only limited evidence-based scientific knowledge in the cardiogenic shock setting. Therefore, recommendations and actual treatments are often based on retrospective or prospective registry data and extrapolations from randomised clinical trials in acute myocardial infarction patients without cardiogenic shock. This position statement will summarise the current consensus of the diagnosis and treatment of patients with acute myocardial infarction complicated by cardiogenic shock based on current evidence and will provide advice for clinical practice.

Protocol for a multicentre randomised controlled trial evaluating the effects of moderate hypothermia versus normothermia on mortality in patients with refractory cardiogenic shock rescued by venoarterial extracorporeal membrane oxygenation (VA-ECMO) (HYPO-ECMO study)

INTRODUCTION

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is widely used to support the most severe forms of cardiogenic shock (CS). Nevertheless, despite extracorporeal membrane oxygenation (ECMO) use, mortality still remains high (50%). Moderate hypothermia (MH) (33°C-34°C) may improve cardiac performance and decrease ischaemia-reperfusion injuries. The use of MH during VA-ECMO is strongly supported by experimental and preliminary clinical data.

METHODS AND ANALYSIS

The Hypothermia-Extracorporeal Membrane Oxygenation (HYPO-ECMO) study is a multicentre, prospective, controlled randomised trial between an MH group (33°C≤T°C≤34°C) and normothermia group (36°C≤T°C≤37°C). The primary endpoint is all-cause mortality at day 30 following randomisation. The study will also assess as secondary endpoints the effects of targeted temperature management strategies on (1) mortality rate at different time points, (2) organ failure and supportive treatment use and (3) safety. All intubated adults with refractory CS supported with VA-ECMO will be screened. Exclusion criteria are patients having undergone cardiac surgery for heart transplantation or left or biventricular assist device implantation, acute poisoning with cardiotoxic drugs, pregnancy, uncontrolled bleeding and refractory cardiac arrest.Three-hundred and thirty-four patients will be randomised and followed up to 6 months to detect a 15% difference in mortality. Data analysis will be intention to treat. The differences between the two study groups in the risk of all-cause mortality at day 30 following randomisation will be studied using logistic regression analysis adjusted for postcardiotomy setting, prior cardiac arrest, prior myocardial infarction, age, vasopressor dose, Sepsis-related Organ Failure Assessment (SOFA) score and lactate at randomisation.

ETHICS AND DISSEMINATION

Ethics approval has been granted by the Comité de Protection des Personnes Est III Ethics Committee. The trial has been approved by the French Health Authorities (Agence Nationale de la Sécurité du Médicament et des Produits de Santé). Dissemination of results will be performed via journal articles and presentations at national and international conferences. Since this study is also the first step in the constitution of an 'ECMO Trials Group', its results will also be disseminated by the aforementioned group.

TRIAL REGISTRATION NUMBER

NCT02754193.