Myocardial Dysfunction and Shock after Cardiac Arrest

Molar Sodium Lactate Attenuates the Severity of Postcardiac Arrest Syndrome: A Preclinical Study

OBJECTIVES

To determine whether continuous IV infusion of molar sodium lactate would limit cardiac arrest-induced neurologic injury and cardiovascular failure.

DESIGN

Randomized blinded study (animal model).

SETTING

University animal research facility.

SUBJECTS

Twenty-four adult male "New Zealand White" rabbits.

INTERVENTIONS

Anesthetized rabbits underwent 12.5 minutes of asphyxial cardiac arrest and were randomized to receive either normal saline (control group, n = 12) or molar sodium lactate (molar sodium lactate group, n = 12) at a rate of 5 mL/kg/hr during the whole 120-minute reperfusion period.

MEASUREMENTS AND MAIN RESULTS

Pupillary reactivity (primary outcome), levels of S100β protein, in vitro brain mitochondria functions, cardiovascular function, and fluid balance were assessed. Molar sodium lactate reduced brain injury, with a higher proportion of animals exhibiting pupillary reactivity to light (83% vs 25% in the CTRL group, p = 0.01) and lower S100β protein levels (189 ± 42 vs 412 ± 63 pg/mL, p < 0.01) at the end of the protocol. Molar sodium lactate significantly prevented cardiac arrest-induced decrease in oxidative phosphorylation and mitochondrial calcium-retention capacity compared with controls. At 120 minutes of reperfusion, survival did not significantly differ between the groups (10/12, 83% in the molar sodium lactate group vs nine of 12, 75% in the control group; p > 0.99), but hemodynamics were significantly improved in the molar sodium lactate group compared with the control group (higher mean arterial pressure [49 ± 2 vs 29 ± 3 mm Hg; p < 0.05], higher cardiac output [108 ± 4 vs 58 ± 9 mL/min; p < 0.05], higher left ventricle surface shortening fraction [38% ± 3% vs 19% ± 3%; p < 0.05], and lower left ventricular end-diastolic pressure [3 ± 1 vs 8 ± 2 mm Hg; p < 0.01]). While fluid intake was similar in both groups, fluid balance was higher in control animals (11 ± 1 mL/kg) than that in molar sodium lactate-treated rabbits (1 ± 3 mL/kg; p < 0.01) due to lower diuresis.

CONCLUSIONS

Molar sodium lactate was effective in limiting the severity of the postcardiac arrest syndrome. This preclinical study opens up new perspectives for the treatment of cardiac arrest.

CD14 Involvement in Third-degree Skin Burn-induced Myocardial Injury via the MAPK Signaling Pathway

This study investigated the potential genes and related pathways in burn-induced myocardial injury. Rat myocardial injury induced by third-degree burn and the histopathological structures, apoptosis, and cardiac injury markers were then identified using hematoxylin & eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining, and enzyme-linked immunosorbent assay. Next, differentially expressed mRNAs were screened through next-generation sequencing (NGS), followed by functional annotation and key gene validation through quantitative reverse transcription-polymerase chain reaction. Subsequently, CD14 was screened out, and small interfering RNAs against CD14 were transfected to H9C2 cells to further verify the role of CD14 in burn-induced injury. The results showed that third-degree burn could markedly damage the structure of myocardial tissue, induce the apoptosis of myocardial cells, and increase the levels of myocardial injury-related markers, suggesting that burns could induce myocardial injury in rats. Besides, NGS data discovered that third-degree burn could result in 416 differentially upregulated mRNAs and 285 differentially downregulated mRNAs in myocardial tissue. It was also disclosed that differentially expressed mRNAs were mainly enriched in the phosphatidylinositol 3-kinase/Akt, mitogen-activated protein kinase (MAPK), and tumor necrosis factor signaling pathways. Furthermore, cell viability was significantly decreased in H9C2 cells treated with 10% rat burn serum. CD14 was significantly differentially expressed and screened out for further studies. Treatment with burn serum can significantly upregulate the phosphorylation level of extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinase and the expression of cleaved caspase-3 and downregulate the expression of Bcl2 when compared with those in negative control of small interfering RNA transfected H9C2 cells, whereas interfering with CD14 expression reversed the effects of burn serum. The study demonstrated that burn serum treatment could activate the MAPK signaling pathway to promote cell apoptosis, and it can be reversed by interfering with the expression of CD14.

Associations of Vasopressor Requirements With Echocardiographic Parameters After Out-of-Hospital Cardiac Arrest

BACKGROUND

Post-arrest hypotension is common after out of hospital cardiac arrest (OHCA) and many patients resuscitated after OHCA will require vasopressors. We sought to determine the associations between echocardiographic parameters and vasopressor requirements in OHCA patients.

METHODS

We retrospectively analyzed adult patients with OHCA treated with targeted temperature management between December 2005 and September 2016 who underwent a transthoracic echocardiogram (TTE). Categorical variables were compared using 2-tailed Fisher's exact and Pearson's correlation coefficients and variance (r²) values were used to assess relationships between continuous variables.

RESULTS

Among 217 included patients, the mean age was 62 ± 12 years, including 74% males. The arrest was witnessed in 90%, the initial rhythm was shockable in 88%, and 58% received bystander CPR. At the time of TTE, 41% of patients were receiving vasopressors; this group of patients was older, had greater severity of illness, higher inpatient mortality and left ventricular ejection fraction (LVEF) was modestly lower (36.8 ± 17.1% vs. 41.4 ± 16.4%, P = 0.04). Stroke volume, cardiac power output and left ventricular stroke work index correlated with number of vasopressors (Pearson r -0.24 to -0.34, all P < 0.002), but the correlation with LVEF was weak (Pearson r -0.13, P = 0.06).

CONCLUSIONS

In patients after OHCA, left ventricular systolic dysfunction was associated with the need for vasopressors, and Doppler TTE hemodynamic parameters had higher correlation coefficients compared with vasopressor requirements than LVEF. This emphasizes the complex nature of shock after OHCA, including pathophysiologic processes not captured by TTE assessment alone.

Combined Therapy With Polyethylene Glycol-20k and MCC950 Preserves Post-Resuscitated Myocardial Function in a Rat Model of Cardiac Arrest and Cardiopulmonary Resuscitation

Background To investigate the therapeutic potential of combined therapy with polyethylene glycol-20k (PEG-20k) and MCC950 on post-resuscitation myocardial function in a rat model of cardiac arrest. Methods and Results Thirty rats were randomized into 5 groups: Sham, Control, PEG-20k, MCC950, PEG-20k+ MCC950. Except for sham, animals were subjected to 6 minutes of ventricular fibrillation followed by 8 minutes cardiopulmonary resuscitation. Two milliliters PEG-20k was administered by intravenous injection coincident with the start of cardiopulmonary resuscitation; MCC950 (10 mg/kg), a highly selective NLRP3 inflammasome inhibitor, was delivered immediately after restoration of spontaneous circulation. Myocardial function, sublingual microcirculation, mitochondrial function, plasma cardiac troponin I, and interleukin-1β, expression of proteins in SIRT1 (sirtuin 1)/PGC-1α (peroxisome proliferator-activated receptor gamma coactivator 1-alpha) and NLRP3 (the NOD-like receptor family protein 3) inflammasome pathways were evaluated. Following cardiopulmonary resuscitation, myocardial function was compromised with a significantly decreased cardiac output, ejection fraction, and increased myocardial performance index, cardiac troponin I. Sublingual microcirculation was disturbed with impaired perfused vessel density and microvascular flow index. Cardiac arrest reduced mitochondrial routine respiration, Complex I-linked respiration, respiratory control rates and oxidative phosphorylation coupling efficiency. PEG-20k or MCC950 alone restored mitochondrial respiratory function, restituted sublingual microcirculation, and preserved myocardial function, whereas a combination of PEG-20k and MCC950 further improved these aspects. PEG-20k restored the expression of SIRT1 and PGC-1α, and blunted activation of NLRP3 inflammasomes. MCC950 suppressed expression of cleaved-caspase-1/pro-caspase-1, ASC (apoptosis-associated speck-like protein), GSDMD [gasdermin d], and interleukin-1β. Conclusions Combined therapy with PEG-20k and MCC950 is superior to either therapy alone for preserving post-resuscitated myocardial function, restituting sublingual microcirculation at restoration of spontaneous circulation at 6 hours. The responsible mechanisms involve upregulated expression of SIRT1/PGC1-α in tandem with inhibition of NLRP3 inflammasomes.

Effect of the KCa3.1 blocker, senicapoc, on cerebral edema and cardiovascular function after cardiac arrest - A randomized experimental rat study

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Senicapoc was successfully administered intravenously.

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Senicapoc did not reduce cerebral edema 4 h after cardiac arrest.

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Senicapoc did not increase mean arterial pressure within 4 h from resuscitation.

Aim

Formation of cerebral edema and cardiovascular dysfunction may worsen brain injury following cardiac arrest. We hypothesized that administration of the intermediate calcium-activated potassium (KCa3.1) channel blocker, senicapoc, would reduce cerebral edema and augment mean arterial pressure in the early post-resuscitation period.

Method

Male Sprague-Dawley rats, aged 11–15 weeks, were utilized in the study. Rats were exposed to 8 min of asphyxial cardiac arrest. Shortly after resuscitation, rats were randomized to receive either vehicle or senicapoc (10 mg/kg) intravenously. The primary outcome was cerebral wet to dry weight ratio 4 h after resuscitation. Secondary outcomes included mean arterial pressure, cardiac output, norepinephrine dose, inflammatory cytokines and neuron specific enolase levels. Additionally, a sub-study was conducted to validate intravenous administration of senicapoc.

Results

The sub-study revealed that senicapoc-treated rats maintained a significantly higher mean arterial pressure during administration of SKA-31 (a KCa3.1 channel opener).

The plasma concentration of senicapoc was 1060 ± 303 ng/ml 4 h after administration. Senicapoc did not reduce cerebral edema or augment mean arterial pressure 4 h after resuscitation. Likewise, cardiac function and norepinephrine dose did not vary between groups. Inflammatory cytokines and neuron specific enolase levels increased in both groups after resuscitation with no difference between groups. Senicapoc enhanced the PaO₂/FiO₂ ratio significantly 4 h after resuscitation.

Conclusion

Senicapoc was successfully administered intravenously after resuscitation, but did not reduce cerebral edema or increase mean arterial pressure in the early post-resuscitation period.

Review of Hypothermia Protocol and Timing of the Echocardiogram

Targeted temperature management, also known as therapeutic hypothermia (TH), is recommended for out-of-hospital cardiac arrest (OHCA). Both internal or external methods of cooling can be applied. Individuals resuscitated from OHCA frequently develop postarrest myocardial dysfunction resulting in decreased cardiac output and left ventricular systolic function. This dysfunction is usually transient and improves with spontaneous recovery over time. Echocardiogram (ECHO) can be a vital tool for the assessment and management of these patients. This manuscript reviewed methods available for TH after OHCA and reviews role of ECHO in the diagnosis and prognosis in this setting.

Inhibiting Cardiac Mitochondrial Fatty Acid Oxidation Attenuates Myocardial Injury in a Rat Model of Cardiac Arrest

Mitochondrial fatty acid oxidation (FAO) is involved in myocardial damage after cardiopulmonary resuscitation (CPR). This study is aimed at investigating the effect of inhibiting mitochondrial FAO on myocardial injury and the underlying mechanisms of postresuscitation myocardial dysfunction. Rats were induced, subjected to 8 min of ventricular fibrillation, and underwent 6 min of CPR. Rats with return of spontaneous circulation (ROSC) were randomly divided into the Sham group, CPR group, and CPR + Trimetazidine (TMZ) group. Rats in the CPR + TMZ group were administered TMZ (10 mg/kg) at the onset of ROSC via the right external jugular vein, while rats in the CPR group were injected with equivalent volumes of vehicle. The sham rats were only administered equivalent volumes of vehicle. We found that the activities of enzymes related to cardiac mitochondrial FAO were partly improved after ROSC. TMZ, as a reversible inhibitor of 3-ketoacyl CoA thiolase, inhibited myocardial mitochondrial FAO after ROSC. In the CPR + TMZ group, the levels of mitochondrial injury in cardiac tissue were alleviated following attenuated myocardial damage and oxidative stress after ROSC. In addition, the disorder of cardiac mitochondrial metabolism was ameliorated, and specifically, the superfluous succinate related to mitochondrial reactive oxygen species (ROS) generation was decreased by inhibiting myocardial mitochondrial FAO with TMZ administration after ROSC. In conclusion, in the early period after ROSC, inhibiting cardiac mitochondrial FAO attenuated excessive cardiac ROS generation and preserved myocardial function, probably by alleviating the dysfunction of cardiac mitochondrial metabolism in a rat model of cardiac arrest.

Biventricular Unloading with Impella and Venoarterial Extracorporeal Membrane Oxygenation in Severe Refractory Cardiogenic Shock: Implications from the Combined Use of the Devices and Prognostic Risk Factors of Survival

Since mechanical circulatory support (MCS) devices have become integral component in the therapy of refractory cardiogenic shock (RCS), we identified 67 patients in biventricular support with Impella and venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO) for RCS between February 2013 and December 2019 and evaluated the risk factors of mortality in this setting. Mean age was 61.07 ± 10.7 and 54 (80.6%) patients were male. Main cause of RCS was acute myocardial infarction (AMI) (74.6%), while 44 (65.7%) were resuscitated prior to admission. The mean Simplified Acute Physiology Score II (SAPS II) and Sequential Organ Failure Assessment Score (SOFA) score on admission was 73.54 ± 16.03 and 12.25 ± 2.71, respectively, corresponding to an expected mortality of higher than 80%. Vasopressor doses and lactate levels were significantly decreased within 72 h on biventricular support (p < 0.05 for both). Overall, 17 (25.4%) patients were discharged to cardiac rehabilitation and 5 patients (7.5%) were bridged successfully to ventricular assist device implantation, leading to a total of 32.8% survival on hospital discharge. The 6-month survival was 31.3%. Lactate > 6 mmol/L, vasoactive score > 100 and pH < 7.26 on initiation of biventricular support, as well as Charlson comorbity index > 3 and prior resuscitation were independent predictors of survival. In conclusion, biventricular support with Impella and VA-ECMO in patients with RCS is feasible and efficient leading to a better survival than predicted through traditional risk scores, mainly via significant hemodynamic improvement and reduction in lactate levels.

Association of Timing of Electrocardiogram Acquisition After Return of Spontaneous Circulation With Coronary Angiography Findings in Patients With Out-of-Hospital Cardiac Arrest

IMPORTANCE

Electrocardiography (ECG) is an important tool to triage patients with out-of-hospital cardiac arrest (OHCA) after return of spontaneous circulation (ROSC). An immediate coronary angiography after ROSC is recommended only in patients with an ECG that is diagnostic of ST-segment elevation myocardial infarction (STEMI). To date, the benefit of this approach has not been demonstrated in patients with a post-ROSC ECG that is not diagnostic of STEMI.

OBJECTIVE

To assess whether the time from ROSC to ECG acquisition is associated with the diagnostic accuracy of ECG for STEMI.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, multicenter cohort study (the Post-ROSC Electrocardiogram After Cardiac Arrest study) analyzed consecutive patients older than 18 years who were resuscitated from OHCA between January 1, 2015, and December 31, 2018, and were admitted to 1 of the 3 participating centers in Europe (Pavia, Italy; Lugano, Switzerland; and Vienna, Austria).

EXPOSURE

Only patients who underwent coronary angiography during hospitalization and who acquired a post-ROSC ECG before the angiography were enrolled. Patients with a nonmedical cause of OHCAs were excluded.

MAIN OUTCOMES AND MEASURES

The primary end point was false-positive ECG findings, defined as the percentage of patients with post-ROSC ECG findings that met STEMI criteria but who did not show obstructive coronary artery disease on angiography that was worthy of percutaneous coronary angioplasty.

RESULTS

Of 586 consecutive patients who were admitted to the 3 participating centers, 370 were included in the analysis (287 men [77.6%]; median age, 62 years [interquartile range, 53-70 years]); 121 (32.7%) were enrolled in the participating center in Pavia, Italy; 38 (10.3%) in Lugano, Switzerland; and 211 (57.0%) in Vienna, Austria. The percentage of false-positive ECG findings in the first tertile of ROSC to ECG time (≤7 minutes) was significantly higher than that in the second (8-33 minutes) and third (>33 minutes) tertiles: 18.5% in the first tertile vs 7.2% in the second (odds ratio [OR], 0.34; 95% CI, 0.13-0.87; P = .02) and 5.8% in the third (OR, 0.27; 95% CI, 0.15-0.47; P < .001). These differences remained significant when adjusting for sex (≤7 minutes: reference; 8-33 minutes: OR, 0.32; 95% CI, 0.12-0.85; P = .02; >33 minutes: OR, 0.26; 95% CI, 0.14-0.47; P < .001), age (≤7 minutes: reference; 8-33 minutes: OR, 0.34; 95% CI, 0.13-0.89; P = .03; >33 minutes: OR, 0.27; 95% CI, 0.15-0.46; P < .001), number of segments with ST-elevation (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.15-0.81; P = .01; >33 minutes: OR, 0.28; 95% CI, 0.15-0.52; P < .001), QRS duration (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.14-0.87; P = .02; >33 minutes: OR, 0.27; 95% CI, 0.15-0.48; P < .001), heart rate (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.93; P = .04; >33 minutes: OR, 0.29; 95% CI, 0.15-0.55; P < .001), epinephrine administered (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.98; P = .045; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001), shockable initial rhythm (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.96; P = .04; >33 minutes: OR, 0.26; 95% CI, 0.15-0.46; P < .001), and 3 or more shocks administered (≤7 minutes: reference; 8-33 minutes: OR, 0.36; 95% CI, 0.13-1.00; P = .05; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001) in bivariable analyses.

CONCLUSIONS AND RELEVANCE

This study suggests that early ECG acquisition after ROSC in patients with OHCA is associated with a higher percentage of false-positive ECG findings for STEMI. It may be reasonable to delay post-ROSC ECG by at least 8 minutes after ROSC or repeat the acquisition if the first ECG is diagnostic of STEMI and is acquired early after ROSC.

Heart Rate and Neurological Outcomes in Patients Undergoing Targeted Temperature Management

INTRODUCTION

There is a paucity of data evaluating the impact of heart rate (HR) during Targeted Temperature Management (TTM) and neurologic outcomes. Current resuscitation guidelines do not specify a HR goal during TTM. We sought to determine the relationship between HR and neurologic outcomes in a single-center registry dataset.

METHODS

We retrospectively studied 432 consecutive patients who completed TTM (33°C) after cardiac arrest from 2008 to 2017. We evaluated the relationship between neurologic outcomes and HR during TTM. Pittsburgh Cerebral Performance Categories (CPC) at discharge were used to determine neurological recovery. Statistical analysis included chi square, Student's t-test and Mann-Whitney U. A logistic regression model was created to evaluate the strength of contribution of selected variables on the outcome of interest.

RESULTS

Approximately 94,000 HR data points from 432 patients were retrospectively analyzed; the mean HR was 82.17 bpm over the duration of TTM. Favorable neurological outcomes were seen in 160 (37%) patients. The mean HR in the patients with a favorable outcome was lower than the mean HR of those with an unfavorable outcome (79.98 bpm vs 85.67 bpm p < 0.001). Patients with an average HR of 60-91 bpm were 2.4 times more likely to have a favorable neurological outcome compared to than HR's < 60 or > 91 (odds ratio [OR] = 2.36, 95% confidence interval [CI] 1.61-3.46, p < 0.001). Specifically, mean HR's in the 73-82 bpm range had the greatest rate of favorable outcomes (OR 3.56, 95% CI 1.95-6.50), p < 0.001. Administration of epinephrine, a history of diabetes mellitus and hypertension all were associated with worse neurological outcomes independent of HR.

CONCLUSION

During TTM, mean HRs between 60-91 showed a positive association with favorable outcomes. It is unclear whether a specific HR should be targeted during TTM or if heart rates between 60-91 bpm might be a sign of less neurological damage.

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.

Prostaglandin E1 attenuates post‑cardiac arrest myocardial dysfunction through inhibition of mitochondria‑mediated cardiomyocyte apoptosis

Post‑cardiac arrest myocardial dysfunction (PAMD) is a leading cause of death in patients undergoing resuscitation patients following cardiac arrest (CA). Although prostaglandin E1 (PGE1) is a clinical drug used to mitigate ischemia injury, its effect on PAMD remains unknown. In the present study, the protective effects of PGE1 on PAMD were evaluated in a rat model of CA and in a hypoxia‑reoxygenation (H/R) in vitro model. Rats were randomly assigned to CA, CA+PGE1 or sham groups. Asphyxia for 8 min followed by cardiopulmonary resuscitation were performed in the CA and CA+PGE1 groups. PGE1 was intravenously administered at the onset of return of spontaneous circulation (ROSC). PGE1 treatment significantly increased the ejection fraction and cardiac output within 4 h following ROSC and improved the survival rate, compared with the CA group. Moreover, PGE1 inactivated GSK3β, prevented mitochondrial permeability transition pore (mPTP) opening, while reducing cytochrome c and cleaved caspase‑3 expression, as well as cardiomyocyte apoptosis in the rat model. To examine the underlying mechanism, H/R H9c2 cells were treated with PGE1 at the start of reoxygenation. The changes in GSK3β activity, mPTP opening, cytochrome c and cleaved caspase‑3 expression, and apoptosis of H9c2 cells were consistent with those noted in vivo. The results indicated that PGE1 attenuated PAMD by inhibiting mitochondria‑mediated cardiomyocyte apoptosis.

Percutaneous mechanical circulatory support and survival in patients resuscitated from Out of Hospital cardiac arrest: A study from the CARES surveillance group

INTRODUCTION

Maintenance of cardiac function is required for successful outcome after out-of-hospital cardiac arrest (OHCA). Cardiac function can be augmented using a mechanical circulatory support (MCS) device, most commonly an intra-aortic balloon pump (IABP) or Impella®.

OBJECTIVE

Our objective is to assess whether the use of a MCS is associated with improved survival in patients resuscitated from OHCA in Michigan.

METHODS

We matched cardiac arrest cases during 2014-2017 from the Cardiac Arrest Registry to Enhance Survival (CARES) in Michigan and the Michigan Inpatient Database (MIDB) using probabilistic linkage. Multilevel logistic regression tested the association between MCS and the primary outcome of survival to hospital discharge.

RESULTS

A total of 3790 CARES cases were matched with the MIDB and 1131 (29.8%) survived to hospital discharge. A small number were treated with MCS, an IABP (n = 183) or Impella® (n = 50). IABP use was associated with an improved outcome (unadjusted OR = 2.16, 95%CI [1.59, 2.93]), while use of Impella® approached significance (OR = 1.72, 95% CI [0.96, 3.06]). Use of MCS was associated with improved outcome (unadjusted OR = 2.07, 95% CI [1.55, 2.77]). In a multivariable model, MCS use was no longer independently associated with improved outcome (OR_adj = 0.95, 95% CI [0.69, 1.31]). In the subset of subjects with cardiogenic shock (N = 725), MCS was associated with improved survival in univariate (unadjusted OR = 1.84, 95% CI [1.24, 2.73]) but not multi-variable modeling (OR_adj = 1.14, 95% CI [0.74, 1.77]).

CONCLUSION

Use of MCS was infrequent in patients resuscitated from OHCA and was not independently associated with improvement in post arrest survival after adjusting for covariates.

Cardiac Complications Following Cardiac Surgery Procedures

BACKGROUND

Elderly patients and those with multiple concomitant disorders are nowadays qualified for cardiac surgery procedures, which is related to higher incidence of the postoperative complications.

AIM

The aim of this study was a retrospective analysis of the perioperative factors potentially contributing to occurrence of cardiac incidents after cardiac surgery procedures.

METHODS

Data of 552 patients of the cardiac surgery clinic were collected and analyzed. Data concerning medical history, previous treatment, laboratory results, additional tests results, operation and hospitalization period were examined.

RESULTS

In the study population of 552 patients, cardiac complications were observed in 49.5% of them. Among cardiac complications, the most frequent were supraventricular tachycardia (30.1%) and atrial fibrillation (27.4%). Postoperative bradycardia occurred in 5.25% patients, half of whom required temporary cardiac pacing.

CONCLUSIONS

The risk of incidence of cardiac complications after cardiac surgery procedures depends mostly on patient's age, EuroSCORE Logistic (ESL) score, left ventricular ejection fraction, myocardial hypertrophy, presence of paroxysmal AF and coincidence of nephrological complications. The necessity of performing more than one heart defibrillation after removing aortic cross-clamp favors early postoperative bradycardia. Considering the outcomes of this study, continuing reperfusion at least until 1/3 of the aortic cross-clamp time brings no additional benefits to the patients.

Cardiac function after cardiac arrest: what do we know?

Postcardiac arrest myocardial dysfunction (PCAMD) is a frequent complication faced during post-resuscitation care that adversely impacts survival and neurological outcome. Both mechanical and electrical factors contribute to the occurrence of PCAMD. Prearrest ventricular function, the cause of cardiac arrest, global ischemia, resuscitation factors, ischemia/reperfusion injury and post-resuscitation treatments contribute to the severity of PCMAD. The pathophysiology of PCAMD is complex and include myocytes energy failure, impaired contractility, cardiac edema, mitochondrial damage, activation of inflammatory pathways and the coagulation cascade, persistent ischemic injury and myocardial stiffness. Hypotension and low cardiac output with vasopressor/inotropes need are frequent after resuscitation. However, clinical, hemodynamic and laboratory signs of shock are frequently altered by cardiac arrest pathophysiology and post-resuscitation treatment, potentially being misleading and not fully reflecting the severity of postcardiac arrest syndrome. Even if validated criteria are lacking, an extensive hemodynamic evaluation is useful to define a "benign" and a "malign" form of myocardial dysfunction and circulatory shock, potentially having treatment and prognostic implications. Cardiac output is frequently decreased after cardiac arrest, particularly in patients treated with target temperature management (TTM); however, it is not independently associated with outcome. Sinus bradycardia during TTM seems independently associated with survival and good neurological outcome, representing a promising prognostic indicator. Higher mean arterial pressure (MAP) seems to be associated with improved survival and cerebral function after cardiac arrest; however, two recent randomized clinical trials failed to replicate these results. Recommendations on hemodynamic optimization are relatively poor and are largely based on general principle of intensive care medicine.

Intravenous calcium as a pressor in a swine model of hypoxic pseudo-pulseless electrical mechanical activity-a preliminary report

BACKGROUND

Pseudo-pulseless electrical activity (pseudo-PEA) is a lifeless form of profound cardiac shock characterized by measurable cardiac mechanical activity without clinically detectable pulses. Pseudo-PEA may constitute up to 40% of reported cases of cardiac arrest. Resuscitation from pseudo-PEA is often associated with hypotension refractory to catecholamine pressors. We hypothesized that this post-resuscitation state may be associated with hypocalcemic hypotension responsive to intravenous calcium.

METHODS

Using pre-existing data from our hypoxic swine pseudo-PEA model, we measured blood pressure, hemodynamics, and electrolytes. Physiological data were analyzed on a heartbeat by heartbeat basis. The midpoint of the calcium response was defined using change of curvature feature detection. Hemodynamic parameters were shifted such that the value at the midpoint was equal to zero.

RESULTS

In 9 animals with refractory hypotension, we administered 37 boluses of intravenous calcium in the dosage range of 5-20 mg. Comparisons were made between the average values in the time period 40-37 s before the midpoint and 35-40 s after the midpoint. Of the 37 administered boluses, 34 manifested a change in the blood pressure, with mean aortic pressure, systolic and diastolic pressures all increasing post bolus administration.

CONCLUSIONS

Administration of intravenous calcium may be associated with a pressor-like response in refractory hypotension after resuscitation from pseudo-PEA. Relative ionized hypocalcemia may cause hypotension after resuscitation from pseudo-PEA. Therapy with intravenous calcium should be further investigated in this setting.

Carbon monoxide improves haemodynamics during extracorporeal resuscitation in pigs

AIMS

Heart disease of different aetiology remains the leading cause of cardiac arrest (CA). Despite efforts to improve the quality of cardiopulmonary resuscitation (CPR), subsequent myocardial and systemic damage after CA still present a major long-term burden. Low-dose carbon monoxide (CO) is known to exert protective effects in cardiovascular pathophysiology but clinical applications are challenged by unfavourable delivery modes. We tested the hypothesis that extracorporeal resuscitation (E-CPR) in combination with controlled fast onset CO delivery results in improved cardiac physiology and haemodynamics. Damage-associated molecular pattern (DAMP) signalling may be part of the molecular mechanism.

METHODS AND RESULTS

In an established porcine model, E-CPR was performed. While E-CPR leads to similar results as compared to a conventional CPR strategy, CO delivery in combination with E-CPR demonstrated significant cardioprotection. Cardiac performance analysis using echocardiography and thermodilution techniques showed a CO-dependent improved cardiac function compared to severe myocardial dysfunction in CPR and E-CPR (left ventricular ejection fraction: Sham 49 ± 5; CPR 26 ± 2; E-CPR 25 ± 2; CO-E-CPR 31 ± 4; P < 0.05). While sublingual microcirculation was significantly compromised in CPR and E-CPR, CO delivery demonstrated a significant improvement in microvascular function (microvascular flow index: Sham 2.9 ± 0.1; CPR 2.2 ± 0.1; E-CPR 1.8 ± 0.1; CO-E-CPR 2.7 ± 0.1; P < 0.01). Histological and serological myocardial damage markers were significantly reduced (hsTroponin-T Sham 0.01 ± 0.001; CPR 1.9 ± 0.2; E-CPR 3.5 ± 1.2; CO-E-CPR 0.5 ± 0.2 ng/mL; P < 0.05). DAMP signalling was decreased ipse facto leading to influence of cardioprotective heat shock and cyclooxygenase response.

CONCLUSIONS

CO treatment restores myocardial function and improves systemic macro- and microhaemodynamics in E-CPR through a reduction in DAMPs.

Risks According to the Timing and Frequency of Hypotension Episodes in Postanoxic Comatose Patients

The aim of this study was to assess the risk of unfavorable outcomes according to the timing of hypotension episodes in cardiac arrest patients. This prospectively conducted multicenter observational study included 1373 out-of-hospital cardiac arrest patients treated with 33 °C targeted temperature management (TTM). Unfavorable neurological outcome and the incidence of complications were analyzed according to the timing of hypotension. Compared with hypotension before TTM initiation (adjusted hazard ratio (aHR) 1.51), hypotension within 6 h after TTM initiation was associated with an increased risk of unfavorable neurologic outcome (aHR 1.693), and after 24 h of TTM, was connected with decreased risk (aHR 1.277). The risk of unfavorable neurological outcome was gradually reduced over time after TTM initiation. Hypotension, persisting both before and during TTM, demonstrated a greater risk (aHR 2) than transient hypotension (aHR 1.265). Hypotension was correlated with various complications. Differences in lactate levels were persistent, regardless of the initial fluid therapy (p < 0.001). Hypotension showed a strong correlation with unfavorable neurological outcome, especially in the early phase after TTM initiation, and complications. It is essential to manage hypotension that occurs at the beginning of TTM initiation to recover cerebral function in cardiac arrest patients.

Rate of intra-arrest epinephrine administration and early post-arrest organ failure after in-hospital cardiac arrest

INTRODUCTION

Data supporting epinephrine administration during resuscitation of in-hospital cardiac arrest (IHCA) are limited. We hypothesized that more frequent epinephrine administration would predict greater early end-organ dysfunction and worse outcomes after IHCA.

METHODS

We performed a retrospective cohort study including patients resuscitated from IHCA at one of 67 hospitals between 2010 and 2019 who were ultimately cared for at a single tertiary care hospital. Our primary exposure of interest was rate of intra-arrest epinephrine bolus administration (mg/min). We considered several outcomes, including severity of early cardiovascular failure (modeled using Sequential Organ Failure Assessment (SOFA) cardiovascular subscore), early neurological and early global illness severity injury (modeled as Pittsburgh Cardiac Arrest Category (PCAC)). We used generalized linear models to test for independent associations between rate of epinephrine administration and outcomes.

RESULTS

We included 695 eligible patients. Mean age was 62 ± 15 years, 416 (60%) were male and 172 (26%) had an initial shockable rhythm. Median arrest duration was 16 [IQR 9-25] min, and median rate of epinephrine administration was 0.2 [IQR 0.1-0.3] mg/min. Higher rate of epinephrine predicted worse PCAC, and lower survival in patients with initial shockable rhythms. There was no association between rate of epinephrine and other outcomes.

CONCLUSION

Higher rates of epinephrine administration during IHCA are associated with more severe early global illness severity.

Comparison of Dopamine and Norepinephrine Use for the Treatment of Hypotension in Out-Of-Hospital Cardiac Arrest Patients with Return of Spontaneous Circulation

In patients experiencing out-of-hospital cardiac arrest (OHCA), hypotension is common after return of spontaneous circulation (ROSC). Both dopamine and norepinephrine are recommended as inotropic therapeutic agents. This study aimed to determine the impact of the use of these two medications on hypotension. This is a multicenter retrospective cohort study. OHCA patients with ROSC were divided into three groups according to the post resuscitation inotropic agent used for treatment in the emergency department, namely, dopamine, norepinephrine, and dopamine and norepinephrine combined therapy. Thirty-day survival and favorable neurologic performance were analyzed among the three study groups. The 30-day survival and favorable neurologic performance rates in the three study groups were 12.5%, 13.0%, and 6.8% as well as 4.9%, 4.3%, and 1.2%, respectively. On controlling the potential confounding factors by logistic regression, there was no difference between dopamine and norepinephrine treatment in survival and neurologic performance (adjusted odds ratio (aOR): 1.0, 95% confidence interval (CI) 0.48-2.06; aOR: 0.8, 95% CI: 0.28-2.53). The dopamine and norepinephrine combined treatment group had worse outcome (aOR: 0.6, 95% CI: 0.35-1.18; aOR: 0.2, 95% CI: 0.05-0.89). In conclusion, there was no significant difference in post-ROSC hypotension treatment between dopamine and norepinephrine in 30-day survival and favorable neurologic performance rates.

Comprehensive Cardiac Care After Cardiac Arrest

Cardiac arrest (CA) results in multiorgan ischemia until return of spontaneous circulation and often is followed by a low-flow shock state. Upon restoration of circulation and organ perfusion, resuscitative teams must act quickly to achieve clinical stability while simultaneously addressing the underlying etiology of the initial event. Optimal cardiovascular care demands focused management of the post-cardiac arrest syndrome and associated shock. Acute coronary syndrome should be considered and managed in a timely manner, because early revascularization improves patient outcomes and may suppress refractory arrhythmias. This review outlines the diagnostic and therapeutic considerations that define optimal cardiovascular care after CA.

N-acetylcysteine alleviates post-resuscitation myocardial dysfunction and improves survival outcomes via partly inhibiting NLRP3 inflammasome induced-pyroptosis

Background

NOD-like receptor 3 (NLRP3) inflammasome is necessary to initiate acute sterile inflammation. Increasing evidence indicates the activation of NLRP3 inflammasome induced pyroptosis is closely related to reactive oxygen species (ROS) in the sterile inflammatory response triggered by ischemia/reperfusion (I/R) injury. N-acetylcysteine (NAC) is an antioxidant and plays a protective role in local myocardial I/R injury, while its effect on post-resuscitation myocardial dysfunction, as well as its mechanisms, remain elusive. In this study, we aimed to investigate the effect of NAC on post-resuscitation myocardial dysfunction in a cardiac arrest rat model, and whether its underlying mechanism may be linked to ROS and NLRP3 inflammasome-induced pyroptosis.

Methods

The rats were randomized into three groups: (1) sham group, (2) cardiopulmonary resuscitation (CPR) group, and (3) CPR + NAC group. CPR group and CPR + NAC group went through the induction of ventricular fibrillation (VF) and resuscitation. After return of spontaneous circulation (ROSC), rats in the CPR and CPR + NAC groups were again randomly divided into two subgroups, ROSC 6 h and ROSC 72 h, for further analysis. Hemodynamic measurements and myocardial function were measured by echocardiography, and western blot was used to detect the expression of proteins.

Results

Results showed that after treatment with NAC, there was significantly better myocardial function and survival duration; protein expression levels of NLRP3, adaptor apoptosis-associated speck-like protein (ASC), Cleaved-Caspase-1 and gasdermin D (GSDMD) in myocardial tissues were significantly decreased; and inflammatory cytokines levels were reduced. The marker of oxidative stress malondialdehyde (MDA) decreased and superoxide dismutase (SOD) increased with NAC treatment.

Conclusions

NAC improved myocardial dysfunction and prolonged animal survival duration in a rat model of cardiac arrest. Moreover, possibly by partly inhibiting ROS-mediated NLRP3 inflammasome-induced pryoptosis.

Shock Severity and Hospital Mortality In Out of Hospital Cardiac Arrest Patients Treated With Targeted Temperature Management

BACKGROUND

Shock in patients resuscitated after out of hospital cardiac arrest (OHCA) is associated with an increased risk of mortality. We sought to determine the associations between lactate level, mean arterial pressure (MAP), and vasopressor/inotrope doses with mortality.

METHODS

Retrospective cohort study of adult patients with OHCA of presumed cardiac etiology treated with targeted temperature management (TTM) between December 2005 and September 2016. Multivariable logistic regression was performed to determine predictors of hospital death.

RESULTS

Among 268 included patients, the median age was 64 (55, 71.8) years, including 27% females. OHCA was witnessed in 89%, OHCA rhythm was shockable in 87%, and bystander CPR was provided in 64%. Vasopressors were required during the first 24 h in 60%. Hospital mortality occurred in 104 (38.8%) patients. Higher initial lactate, peak Vasoactive-Inotropic Score (VIS), and lower mean 24-h MAP were associated with higher hospital mortality (all P < 0.001). After multivariable regression, both higher initial lactate (adjusted OR 1.15 per 1 mmol/L higher, 95% CI 1.00-1.31, P = 0.03) and higher peak VIS (adjusted OR 1.20 per 10 units higher, 95% CI 1.10-1.54, P = 0.003) were associated with higher hospital mortality, but mMAP was not (P = 0.92). However, patients with a mMAP < 70 mm Hg remained at higher risk of hospital mortality after multivariable adjustment (adjusted OR 9.30, 95% CI 1.39-62.02, P = 0.02).

CONCLUSIONS

In patients treated with TTM after OHCA, greater shock severity, as reflected by higher lactate levels, mMAP < 70 mmHg, and higher vasopressor requirements during the first 24 h was associated with an increased rate of hospital mortality.

Neurological outcome in patients after successful resuscitation in out-of-hospital settings

Neurological outcome is an important determinant of death in admitted survivors after out-of-hospital cardiac arrest (OHCA). Studies demonstrated several significant pre-hospital predictors of ischemic brain injury (time to resuscitation, time of resuscitation, and cause of OHCA). Our aim was to evaluate the relationship between post-resuscitation clinical parameters and neurological outcome in OHCA patients, when all recommended therapeutic strategies, including hypothermia, were on board. We retrospectively included consecutive 110 patients, admitted to the medical ICU after successful resuscitation due to OHCA. Neurological outcome was defined by cerebral performance category (CPC) scale I-V. CPC categories I-II defined good neurological outcome and CPC categories III-V severe ischemic brain injury. Therapeutic measures were aimed to achieve optimal circulation and oxygenation, early percutaneous coronary interventions (PCI) in acute coronary syndromes (ACS), and therapeutic hypothermia to improve survival and neurological outcome of OHCA patients. We observed good neurological outcome in 37.2% and severe ischemic brain injury in 62.7% of patients. Severe ischemic brain injury was associated significantly with known pre-hospital data (older age, cause of OHCA, and longer resuscitations), but also with increased admission lactate, in-hospital complications (involuntary muscular contractions/seizures, heart failure, cardiogenic shock, acute kidney injury, and mortality), and inotropic and vasopressor support. Good neurological outcome was associated with early PCI, dual antiplatelet therapy, and better survival. We conclude that in OHCA patients, post-resuscitation early PCI and dual antiplatelet therapy in ACS were significantly associated with good neurological outcome, but severe ischemic brain injury was associated with several in-hospital complications and the need for vasopressor and inotropic support.

Stearic acid methyl ester affords neuroprotection and improves functional outcomes after cardiac arrest

Cardiac arrest causes neuronal damage and functional impairments that can result in learning/memory dysfunction after ischemia. We previously identified a saturated fatty acid (stearic acid methyl ester, SAME) that was released from the superior cervical ganglion (sympathetic ganglion). The function of stearic acid methyl ester is currently unknown. Here, we show that SAME can inhibit the detrimental effects of global cerebral ischemia (i.e. cardiac arrest). Treatment with SAME in the presence of asphyxial cardiac arrest (ACA) revived learning and working memory deficits. Similarly, SAME-treated hippocampal slices after oxygen-glucose deprivation inhibited neuronal cell death. Moreover, SAME afforded neuroprotection against ACA in the CA1 region of the hippocampus, reduced ionized calcium-binding adapter molecule 1 expression and inflammatory cytokines/chemokines, with restoration in mitochondria respiration. Altogether, we describe a unique and uncharted role of saturated fatty acids in the brain that may have important implications against cerebral ischemia.

Successful Heart Transplantation after Cardiopulmonary Resuscitation of Donors

BACKGROUND

 Heart transplantation (HTx) is the best therapy for end-stage heart failure. Unfortunately, death on the waiting list remains a problem. Decreasing the number of rejected organs could increase the donor pool.

METHODS

 A total of 144 patients underwent HTx at our department between 2010 and 2019. Of them, 27 patients received organs of donors with cardiopulmonary resuscitation (CPR) prior to organ donation (donor CPR) and were compared with patients who received organs without CPR (control; n = 117).

RESULTS

 We did not observe any disadvantage in the outcome of the donor CPR group compared with the control group. Postoperative morbidity and 1-year survival (control: 72%; donor CPR: 82%; p = 0.35) did not show any differences. We found no impact of the CPR time as well as the duration between CPR and organ donation, but we found an improved survival rate for donors suffering from anoxic brain injury compared with cerebral injury (p = 0.04).

CONCLUSIONS

 Donor organs should not be rejected for HTx due to resuscitation prior to donation. The need for CPR does not affect the graft function after HTx in both short- and mid-term outcomes. We encourage the use of these organs to increase the donor pool and preserve good results.

Utility and Challenges of an Early Invasive Strategy in Patients Resuscitated From Out-of-Hospital Cardiac Arrest

Out-of-hospital cardiac arrest (OHCA) is frequently triggered by acute myocardial ischemia. Coronary angiography is an important component of post-resuscitation care for patients with OHCA without an evident noncardiac cause, to identify underlying coronary artery disease and allow revascularization. Most patients undergoing coronary angiography after OHCA have obstructive coronary artery disease, and nearly one-half of patients have acute coronary occlusion. Early coronary angiography and percutaneous coronary intervention after OHCA have been associated with improved survival in observational studies, but these studies demonstrate selection bias, and randomized trials are lacking. Selection of patients for coronary angiography after OHCA can be challenging, particularly in comatose patients whose outcomes are driven primarily by anoxic brain injury. As for other patients with acute coronary syndromes, patients with ST-segment elevation after OHCA have a high probability of acute coronary occlusion warranting emergent coronary angiography. Patients with cardiogenic shock after OHCA are a high-risk population also requiring emergent coronary angiography. Among patients in stable condition after OHCA without ST-segment elevation, other clinical predictors can be used to identify those needing early coronary angiography to identify obstructive coronary artery disease. Despite the challenges with early neurological prognostication in comatose patients with OHCA, those with multiple objective markers of poor prognosis appear less likely to benefit from revascularization, and early coronary angiography may be reasonably deferred in appropriately selected patients meeting these criteria. The authors propose an algorithm to guide patient selection for coronary angiography after OHCA that combines clinical predictors of acute coronary occlusion and early clinical predictors of severe brain injury.

[Preclinical management of cardiac arrest-extracorporeal cardiopulmonary resuscitation]

BACKGROUND

The chances of surviving out-of-hospital cardiac arrest (OHCA) are still very low. Despite intensive efforts the outcome has remained relatively poor over many years. In specific situations, new technologies, such as extracorporeal cardiopulmonary resuscitation (eCPR) could significantly improve survival with a good neurological outcome.

OBJECTIVE

Does the immediate restoration of circulation and reoxygenation via eCPR influence the survival rate after OHCA? Is eCPR the new link in the chain of survival?

MATERIAL AND METHODS

Discussion of current study results and guideline recommendations.

RESULTS

The overall survival rates after OHCA have remained at 10-30% over many years. Despite low case numbers more recent retrospective studies showed that an improved outcome can be achieved with eCPR. In selected patient collectives survival with a favorable neurological outcome is possible in 38% of the cases.

CONCLUSION

Survival after cardiac arrest and the subsequent quality of life dependent on many different factors. The time factor, i.e. the avoidance of a no-flow phase and reduction of the low-flow phase is of fundamental importance. The immediate restoration of the circulation and oxygen supply by eCPR can significantly improve survival; however, large randomized, controlled trials are currently not available.

Exploratory analysis of myocardial function after extracorporeal cardiopulmonary resuscitation vs conventional cardiopulmonary resuscitation

Objective

Ventricular unloading is associated with myocardial recovery. We sought to evaluate the association of extracorporeal cardiopulmonary resuscitation (ECPR) on myocardial function after cardiac arrest. We conducted a retrospective exploratory analysis, comparing ejection fraction (EF) after adult cardiac arrest, between ECPR and conventional CPR.

Results

Among 1119 cases of cardiac arrest, 116 had an echocardiogram post-return of spontaneous circulation (ROSC) and were included. Thirty-eight patients had ≥ 2 echocardiograms. ECPR patients had differences in age, hypertension and chronic heart failure. ECPR patients had a lower EF post-ROSC (24% vs 45%; p < 0.01) and were more likely to undergo percutaneous coronary intervention (25% vs 3%; p < 0.01). In multivariate analysis, only ECPR use (β-coeff: 10.4 [95% CI 3.68–17.13]; p < 0.01) independently predicted improved myocardial function. In this exploratory study, EF after cardiac arrest may be more likely to improve among ECPR patients than CCPR patients. Our methodology should be replicated to confirm or refute the validity of our findings.

Cellular Stress and General Pathological Processes

From the viewpoint of the general pathology, most of the human diseases are associated with a limited number of pathogenic processes such as inflammation, tumor growth, thrombosis, necrosis, fibrosis, atrophy, pathological hypertrophy, dysplasia and metaplasia. The phenomenon of chronic low-grade inflammation could be attributed to non-classical forms of inflammation, which include many neurodegenerative processes, pathological variants of insulin resistance, atherosclerosis, and other manifestations of the endothelial dysfunction. Individual and universal manifestations of cellular stress could be considered as a basic element of all these pathologies, which has both physiological and pathophysiological significance. The review examines the causes, main phenomena, developmental directions and outcomes of cellular stress using a phylogenetically conservative set of genes and their activation pathways, as well as tissue stress and its role in inflammatory and para-inflammatory processes. The main ways towards the realization of cellular stress and its functional blocks were outlined. The main stages of tissue stress and the classification of its typical manifestations, as well as its participation in the development of the classical and non-classical variants of the inflammatory process, were also described. The mechanisms of cellular and tissue stress are structured into the complex systems, which include networks that enable the exchange of information with multidirectional signaling pathways which together make these systems internally contradictory, and the result of their effects is often unpredictable. However, the possible solutions require new theoretical and methodological approaches, one of which includes the transition to integral criteria, which plausibly reflect the holistic image of these processes.

Two-dimensional echocardiography after return of spontaneous circulation and its association with in-hospital survival after in-hospital cardiopulmonary resuscitation

This retrospective cohort study investigated the association between in-hospital survival and two-dimensional (2D) echocardiography within 24 hours after the return of spontaneous circulation (ROSC) in patients who underwent in-hospital cardiopulmonary resuscitation (ICPR) after in-hospital cardiopulmonary arrest (IHCA). The 2D-echo and non-2D-echo groups comprised eligible patients who underwent transthoracic 2D echocardiography performed by the cardiology team within 24 hours after ROSC and those who did not, respectively. After propensity score (PS) matching, 142 and 284 patients in the 2D-echo and non-2D-echo groups, respectively, were included. A logistic regression analysis showed that the likelihood of in-hospital survival was 2.35-fold higher in the 2D-echo group than in the non-2D-echo group (P < 0.001). Regarding IHCA aetiology, in-hospital survival after cardiac arrest of a cardiac cause was 2.51-fold more likely in the 2D-echo group than in the non-2D-echo group (P < 0.001), with no significant inter-group difference in survival after cardiac arrest of a non-cardiac cause (P = 0.120). In this study, 2D echocardiography performed within 24 hours after ROSC was associated with better in-hospital survival outcomes for patients who underwent ICPR for IHCA with a cardiac aetiology. Thus, 2D echocardiography may be performed within 24 hours after ROSC in patients experiencing IHCA to enable better treatment.

Resistin and Cardiac Arrest-A Prospective Study

The systemic response to ischemia-reperfusion that occurs after a cardiac arrest (CA) followed by the return of spontaneous circulation leads to endothelial toxicity and cytokine production, both responsible for the subsequent occurrence of severe cardiocirculatory dysfunction and early death. Resistin is emerging as a biomarker of proinflammatory status and myocardial ischemic injury and as a mediator of endothelial dysfunction. The study aimed to analyze the possible associations between several clinical and biological variables and the serum levels of resistin in CA survivors. Forty patients with out-of-hospital resuscitated CA, were enrolled in the study. Demographic, clinical and laboratory data (including serum resistin measurements at admission and at 6, 12, 24, 48 and 72 h) were recorded. For resistin, we calculated the area under the curve (AUC) using the trapezoidal method with measurements from 0 to 12 h, 0 to 24 h, 0 to 48 h and 0 to 72 h. Fifteen (37.5%) patients died in the first 72 h after CA. Cardiovascular comorbidities were present in 65% of patients. The majority of patients had post-CA shock (29 (72.5%)). Resistin serum levels rose in the first 12–24 h and decreased in the next 48–72 h. In univariate analysis, advanced age, longer duration of resuscitation, high sequential organ failure assessment score, high lactate levels, presence of cardiovascular comorbidities and the post-CA shock were associated with higher resistin levels. In multivariate analysis, post-CA shock or cardiovascular comorbidities were independently associated with higher AUCs for resistin for 0–12 h and 0–24 h. The only identified variable to independently predict higher AUCs for resistin for 0–48 h and 0–72 h was the presence of post-CA shock. Our data demonstrate strong independent correlation between high serum resistin levels, cardiac comorbidities and post-CA shock. The impact of the post-CA shock on serum concentration of resistin was greater than that of cardiac comorbidities.

The Impact of Emergency Interventions and Patient Characteristics on the Risk of Heart Failure in Patients with Nontraumatic OHCA

Background

Since out-of-hospital cardiac arrest- (OHCA-) related dysfunction (ischemic/reperfusion injury and inflammatory response) might result in long-term impairment, we suspect that new-onset heart failure might be common in long-term survivors. However, these relationships had not been well addressed, and we aimed to analyze the impact of emergency interventions and patient characteristics on the risk of new-onset heart failure in patients with nontraumatic OHCA.

Methods

The Taiwanese government healthcare database contains data for 49,101 nontraumatic OHCA adult patients from 2011-2012, which were analyzed in this study. Nontraumatic OHCA patients who survived to the intensive care unit (ICU) were included as the study group (n = 7,321). Matched patients (n = 21,963) were recruited as a comparison group. Patients with any history of heart failure or cardiac arrest were not included in either group. All patients were followed-up for 6 months for the identification of new-onset heart failure. Adjustments were made for demographics, age, emergency interventions, and comorbidities as potential risk factors.

Results

In all, 3.84% (n = 281) of OHCA patients suffered new-onset heart failure, while only 1.24% (n = 272) of matched patients in the comparison group suffered new-onset heart failure. Strong risk factors for heart failure were age (60-75 years, HR: 11.4; 95% CI: 9-14.4), medical history (myocardial infarction, HR: 2.47; 95% CI: 2.05-2.98 and cardiomyopathy, HR: 2.94; 95% CI: 1.45-5.94), and comorbidities during hospitalization (ischemic heart disease, HR: 4.5; 95% CI: 3.46-5.86). Only extracorporeal membrane oxygenation (ECMO) decreased the risk of heart failure. Most (53.6%) heart failure events occurred within 60 days after OHCA.

Conclusion

An age from 61 to 75 years, a history of myocardial infarction or cardiomyopathy, and ischemic heart disease or infection as comorbidities occurring during hospitalization were strong risk factors for new-onset heart failure in OHCA patients. However, ECMO could decrease this risk. More importantly, most heart failure events occurred within 60 days after OHCA.

Search for Therapeutic Agents for Cardiac Arrest Using a Drug Discovery Tool and Large-Scale Medical Information Database

The survival rate of cardiac arrest patients is less than 10%; therefore, development of a therapeutic strategy that improves their prognosis is necessary. Herein, we searched data collected from medical facilities throughout Japan for drugs that improve the survival rate of cardiac arrest patients. Candidate drugs, which could improve the prognosis of cardiac arrest patients, were extracted using “TargetMine,” a drug discovery tool. We investigated whether the candidate drugs were among the drugs administered within 1 month after cardiac arrest in data of cardiac arrest cases obtained from the Japan Medical Data Center. Logistic regression analysis was performed, with the explanatory variables being the presence or absence of the administration of those candidate drugs that were administered to ≥10 patients and the objective variable being the “survival discharge.” Adjusted odds ratios for survival discharge were calculated using propensity scores for drugs that significantly improved the proportion of survival discharge; the influence of covariates, such as patient background, medical history, and treatment factors, was excluded by the inverse probability-of-treatment weighted method. Using the search strategy, we extracted 165 drugs with vasodilator activity as candidate drugs. Drugs not approved in Japan, oral medicines, and external medicines were excluded. Then, we investigated whether the candidate drugs were administered to the 2,227 cardiac arrest patients included in this study. The results of the logistic regression analysis showed that three (isosorbide dinitrate, nitroglycerin, and nicardipine) of seven drugs that were administered to ≥10 patients showed significant association with improvement in the proportion of survival discharge. Further analyses using propensity scores revealed that the adjusted odds ratios for survival discharge for patients administered isosorbide dinitrate, nitroglycerin, and nicardipine were 3.35, 5.44, and 4.58, respectively. Thus, it can be suggested that isosorbide dinitrate, nitroglycerin, and nicardipine could be novel therapeutic agents for improving the prognosis of cardiac arrest patients.

Anticoagulation therapy could improve the restoration of sinus rhythm and spontaneous circulation in hospital patients with CPR

Objective

To analyse the role of anticoagulation therapy in cardiopulmonary resuscitation (CPR) following an in-hospital cardiac arrest.

Methods

This single-centre retrospective cohort study enrolled patients treated with in-hospital CPR that met the inclusion and exclusion criteria. The patients were divided into a without anticoagulation group and an anticoagulation group. The main outcome measures were the restoration of spontaneous respiration, restoration of sinus rhythm (ROSR), restoration of spontaneous circulation (ROSC) and the hospital mortality.

Results

The study analysed 344 patients: 272 in the without anticoagulation group and 72 in the anticoagulation group. Multiple logistic regression analyses demonstrated that anticoagulation therapy improved ROSR (adjusted odds ratio [OR] 2.21, 95% confidence interval [CI] 1.23, 3.96) and ROSC (adjusted OR 1.91, 95% CI 1.08, 3.40), but it did not improve the restoration of spontaneous respiration (adjusted OR 1.64, 95% CI 0.72, 3.76) and hospital survival (adjusted OR 0.90, 95% CI 0.40, 1.99).

Conclusion

Anticoagulation therapy improved ROSR and ROSC, but did not decrease the mortality rate of hospitalized patients undergoing CPR following in-hospital cardiac arrest.

Hydrogen Inhalation is Superior to Mild Hypothermia for Improving Neurological Outcome and Survival in a Cardiac Arrest Model of Spontaneously Hypertensive Rat

BACKGROUND

Postcardiac arrest syndrome is the consequence of whole-body ischemia-reperfusion events that lead to multiple organ failure and eventually to death. Recent animal studies demonstrated that inhalation of hydrogen greatly mitigates postresuscitation myocardial dysfunction and brain injury. However, the influence of underlying heart disease on the efficacy of hydrogen is still unknown. In the present study, we investigated the effects of hydrogen inhalation on neurological outcome and survival in a cardiac arrest model of spontaneously hypertensive rat (SHR).

METHODS

Cardiopulmonary resuscitation was initiated after 4 min of untreated ventricular fibrillation in 40 SHRs. Immediately after successful resuscitation, animals were randomized to be ventilated with 98% oxygen and 2% nitrogen under normothermia (Ctrl), 2% nitrogen under hypothermia (TH), 2% hydrogen under normothermia (H2), or 2% hydrogen under hypothermia (H2+TH) for 2 h. Hypothermia was maintained at 33°C for 2 h. Animals were observed up to 96 h for assessment of survival and neurologic recovery.

RESULTS

No statistical differences in baseline measurements were observed among groups and all the animals were successfully resuscitated. Compared with Ctrl, serum cardiac troponin T measured at 5 h and myocardial damage score measured at 96 h after resuscitation were markedly reduced in H2, TH, and H2+TH groups. Compared with Ctrl and TH, astroglial protein S100 beta measured during the earlier postresuscitation period, and neurological deficit score and neuronal damage score measured at 96 h were considerably lower in both H2 and H2+TH groups. Ninety-six hours survival rates were significantly higher in the H2 (80.0%) and H2+TH (90.0%) groups than TH (30.0%) and to Ctrl (30.0%).

CONCLUSIONS

Hydrogen inhaling was superior to mild hypothermia for improving neurological outcome and survival in cardiac arrest and resuscitation model of systemic hypertension rats.

Can Systemic Thrombolysis Improve Prognosis of Cardiac Arrest Patients During Cardiopulmonary Resuscitation? A Systematic Review and Meta-Analysis

BACKGROUND

Cardiac arrests are caused in most cases by thromboembolic diseases, such as acute myocardial infarction (AMI) and pulmonary embolism (PE).

OBJECTIVE

We aimed to ascertain the associations of thrombolytic therapy with potential benefits among cardiac arrest patients during cardiopulmonary resuscitation (CPR).

METHODS

We searched PubMed, Embase, and Cochrane databases for studies that evaluated systemic thrombolysis in cardiac arrest patients. The primary outcome was survival to hospital discharge, and secondary outcomes included return of spontaneous circulation (ROSC), 24-h survival rate, hospital admission rate, and bleeding complications.

RESULTS

Nine studies with a total of 4384 cardiac arrest patients were pooled in the meta-analysis, including 1084 patients receiving systemic thrombolysis and 3300 patients receiving traditional treatments. Compared with conventional therapies, the use of systemic thrombolysis did not significantly improve survival to hospital discharge (13.5% vs. 10.8%; risk ratio [RR] 1.13; 95% confidence interval [CI] 0.92-1.39; p = 0.24, I² = 35%), ROSC (50.9% vs. 44.3%; RR 1.29; 95% CI 1.00-1.66; p = 0.05, I² = 73%), and 24-h survival (28.1% vs. 25.6%; RR 1.25; 95% CI 0.88-1.77; p = 0.22, I² = 63%). We observed higher hospital admission rates for patients receiving systemic thrombolysis (43.4% vs. 30.6%; RR 1.53; 95% CI 1.04-2.24; p = 0.03, I² = 87%). In addition, higher risk of bleeding was observed in the thrombolysis group (8.8% vs. 5.0%; RR 1.65; 95% CI 1.16-2.35; p = 0.005, I² = 7%).

CONCLUSIONS

Systemic thrombolysis during CPR did not improve hospital discharge rate, ROSC, and 24-h survival for cardiac arrest patients. Patients receiving thrombolytic therapy have a higher risk of bleeding. More high-quality studies are needed to confirm our results.

Molecular Understanding of the Cardiomodulation in Myocardial Infarction and the Mechanism of Vitamin E Protections

:

Myocardial infarction is a major cause of deaths globally. Modulation of several molecular mechanisms occurs during the initial stages of myocardial ischemia prior to permanent cardiac tissue damage, which involves both pathogenic as well as survival pathways in the cardiomyocyte. Currently, there is increasing evidence regarding the cardioprotective role of vitamin E in alleviating the disease. This fat-soluble vitamin does not only act as a powerful antioxidant; but it also has the ability to regulate several intracellular signalling pathways including HIF-1, PPAR-γ, Nrf-2, and NF-κB that influence the expression of a number of genes and their protein products. Essentially, it inhibits the molecular progression of tissue damage and preserves myocardial tissue viability. This review aims to summarize the molecular understanding of the cardiomodulation in myocardial infarction as well as the mechanism of vitamin E protection.

Effects of Polyethylene Glycol-20k on Postresuscitation Myocardial and Cerebral Function in a Rat Model of Cardiopulmonary Resuscitation

OBJECTIVES

Polyethylene glycol-20k is a hybrid cell impermeant that reduces ischemia injury and improves microcirculatory flow during and following low flow states through nonenergy-dependent water transfer in the microcirculation. We investigated the effects of polyethylene glycol-20k on postresuscitation microcirculation, myocardial and cerebral function, and duration of survival in a rat model of cardiopulmonary resuscitation.

DESIGN

Ventricular fibrillation was induced in 20 male Sprague Dawley rats and untreated for 6 minutes. Animals were randomized into two groups (n = 10 for each group): polyethylene glycol-20k and control. Polyethylene glycol-20k (10% solution in saline, 10% estimated blood volume) and vehicle (saline) were administered at the beginning of cardiopulmonary resuscitation by continuous IV infusion. Resuscitation was attempted after 8 minutes of cardiopulmonary resuscitation.

SETTING

University-Affiliated Research Laboratory.

SUBJECTS

Sprague Dawley Rats.

INTERVENTIONS

Polyethylene glycol-20k.

MEASUREMENTS AND MAIN RESULTS

Buccal microcirculation was measured at baseline, 1, 3, and 6 hours after return of spontaneous circulation using a side-stream dark-field imaging device. Myocardial function was measured by echocardiography at baseline and every hour postresuscitation for 6 hours. The animals were then returned to their cage and observed for an additional 72 hours. Neurologic Deficit Scores were recorded at 24, 48, and 72 hours after resuscitation. Postresuscitation ejection fraction, cardiac output, and myocardial performance index were significantly improved in animals treated with polyethylene glycol-20k (p < 0.05). Perfused buccal vessel density and microcirculatory flow index values were significantly higher at all time points in the polyethylene glycol-20k group compared with the control group. Postresuscitation cerebral function and survival rate were also significantly improved in animals that received polyethylene glycol-20k.

CONCLUSIONS

Administration of polyethylene glycol-20k following cardiopulmonary resuscitation improves postresuscitation myocardial and cerebral function, buccal microcirculation, and survival in a rat model of cardiopulmonary resuscitation.

Tissue-Specific Metabolic Profiles After Prolonged Cardiac Arrest Reveal Brain Metabolome Dysfunction Predominantly After Resuscitation

Background

Cardiac arrest (CA) has been a leading cause of death for many decades. Despite years of research, we still do not understand how each organ responds to the reintroduction of blood flow after prolonged CA. Following changes in metabolites of individual organs after CA and resuscitation gives context to the efficiency and limitations of current resuscitation protocols.

Methods and Results

Adult male Sprague–Dawley rats were arbitrarily assigned into 3 groups: control, 20 minutes of CA, or 20 minutes of CA followed by 30 minutes of cardiopulmonary bypass resuscitation. The rats were euthanized by decapitation to harvest brain, heart, kidney, and liver tissues. The obtained tissue samples were analyzed by ultra‐high‐performance liquid chromatography–high‐accuracy mass spectrometry for comprehensive metabolomics evaluation. After resuscitation, the brain showed decreased glycolysis metabolites and fatty acids and increased amino acids compared with control. Similarly, the heart displayed alterations mostly in amino acids. The kidney showed decreased amino acid and fatty acid pools with severely increased tricarboxylic acid cycle metabolites following resuscitation, while the liver showed minimal alterations with slight changes in the lipid pool. Each tissue has a distinct pattern of metabolite changes after ischemia/reperfusion. Furthermore, resuscitation worsens the metabolic dysregulation in the brain and kidney, while it normalizes metabolism in the heart.

Conclusions

Developing metabolic profiles using a global metabolome analysis identifies the variable nature of metabolites in individual organs after CA and reperfusion, establishing a stark contrast between the normalized heart and liver and the exacerbated brain and kidney, only after the reestablishment of blood circulation.

Extracorporeal membrane oxygenation mitigates myocardial injury and improves survival in porcine model of ventricular fibrillation cardiac arrest

INTRODUCTION

Despite decades of improved strategy in conventional cardiopulmonary resuscitation (CCPR), survival rates of favorable neurological outcome after cardiac arrest (CA) remains poor. It is indicated that the survival rate of successful resuscitation of extracorporeal membrane oxygenation (ECMO) is superior to that of CCPR. But the effect of ECMO in heart is unclear. We aimed to investigate whether ECMO produces cardiac protection by ameliorating post-ischemia reperfusion myocardial injury and myocardial apoptosis.

METHODS

After undergoing 8-min untreated ventricle fibrillation (VF) and 6-min basic life support, 20 male pigs were ultimately used in this study and randomly divided into two groups: CCPR group (n = 10) and extracorporeal CPR (ECPR) group (n = 10). Hemodynamics and blood samples were obtained at baseline and 1, 2, 4, and 6 h during resuscitation. The successfully resuscitated pigs were sacrificed at 6 h after return of spontaneous circulation (ROSC), and the hearts were removed and analyzed under electron microscopy, and immunohistochemistry, quantitative real-time polymerase chain reaction, and immunofluorescence staining assay were performed to evaluate myocardial injury and myocardial apoptosis.

RESULTS

There were no significant differences at basic hemodynamic status between the two groups. The survival rate of ECPR was significantly higher than CCPR group (10/10 [100%] vs. 4/10 [40%], P = 0.04). Compared to CCPR group, ECPR group exhibited a better outcome in hemodynamic function. Cardiac function was significantly impaired after ROSC in both groups, but left ventricular ejection fraction (LVEF) was significantly elevated in ECPR group than CCPR group. The expression of myocardial injury biomarkers (CK-MB, cTNI, H-FABP), endothelial injury biomarker (sP-selectin), and cardiac function biomarker (BNP) were remarkably increased after ROSC in both groups, but low levels in ECPR group than in CCPR group. Cardiomyocytes injury was attenuated in ECPR group under transmission electron microscopy (TEM). Typical apoptotic nuclei of cardiomyocytes were significantly reduced and oxidative damage were attenuated in ECPR group.

CONCLUSIONS

During prolonged VF-induced CA, ECPR contributes to improving hemodynamics, attenuating myocardial ischemia-reperfusion injury, ameliorating myocardial ultra structure, improving cardiac function, and elevating survival rate by preventing oxidative damage, regulating energy metabolism, inhibiting cardiomyocyte apoptosis.

Pediatric Post–Cardiac Arrest Care: A Scientific Statement From the American Heart Association

Successful resuscitation from cardiac arrest results in a post–cardiac arrest syndrome, which can evolve in the days to weeks after return of sustained circulation. The components of post–cardiac arrest syndrome are brain injury, myocardial dysfunction, systemic ischemia/reperfusion response, and persistent precipitating pathophysiology. Pediatric post–cardiac arrest care focuses on anticipating, identifying, and treating this complex physiology to improve survival and neurological outcomes. This scientific statement on post–cardiac arrest care is the result of a consensus process that included pediatric and adult emergency medicine, critical care, cardiac critical care, cardiology, neurology, and nursing specialists who analyzed the past 20 years of pediatric cardiac arrest, adult cardiac arrest, and pediatric critical illness peer-reviewed published literature. The statement summarizes the epidemiology, pathophysiology, management, and prognostication after return of sustained circulation after cardiac arrest, and it provides consensus on the current evidence supporting elements of pediatric post–cardiac arrest care.

Intra-Arrest Administration of Cyclosporine and Methylprednisolone Does Not Reduce Postarrest Myocardial Dysfunction

Objective

To determine whether the administration of intra-arrest cyclosporine (CCY) and methylprednisolone (MP) preserves left ventricular ejection fraction (LVEF) and cardiac output (CO) after return of spontaneous circulation (ROSC).

Methods

Eleven, 25-30kg female swine were randomized to receive 10mg/kg CCY + 40mg MP or placebo, anesthetized and given a transthoracic shock to induce ventricular fibrillation. After 8 minutes, standard CPR was started. After two additional minutes, the experimental agent was administered. Animals with ROSC were supported for up to 12h with norepinephrine as needed. Echocardiography was performed at baseline, and 1, 2, 6 and 12h post-ROSC. Analysis was performed using generalized estimating equations (GEE) after downsampling continuously sampled data to 5 minute epochs.

Results

Eight animals (64%) achieved ROSC after a median of 7 [IQR 5-13] min of CPR, 2 [ IQR 1-3] doses of epinephrine and 2 [IQR 1-5] defibrillation shocks. Animals receiving CCY+MP had higher post ROSC MAP (GEE coefficient -10.2, P = <0.01), but reduced cardiac output (GEE coefficient 0.8, P = <0.01) compared to placebo. There was no difference in LVEF or vasopressor use between arms.

Conclusions

Intra-arrest cyclosporine and methylprednisolone decreased post-arrest cardiac output and increased mean arterial pressure without affecting left ventricular ejection fraction.