Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock: Results of the ECMO-CS Randomized Clinical Trial.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly being used for circulatory support in patients with cardiogenic shock, although the evidence supporting its use in this context remains insufficient. The ECMO-CS trial (Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock) aimed to compare immediate implementation of VA-ECMO versus an initially conservative therapy (allowing downstream use of VA-ECMO) in patients with rapidly deteriorating or severe cardiogenic shock. METHODS: This multicenter, randomized, investigator-initiated, academic clinical trial included patients with either rapidly deteriorating or severe cardiogenic shock. Patients were randomly assigned to immediate VA-ECMO or no immediate VA-ECMO. Other diagnostic and therapeutic procedures were performed as per current standards of care. In the early conservative group, VA-ECMO could be used downstream in case of worsening hemodynamic status. The primary end point was the composite of death from any cause, resuscitated circulatory arrest, and implementation of another mechanical circulatory support device at 30 days. RESULTS: A total of 122 patients were randomized; after excluding 5 patients because of the absence of informed consent, 117 subjects were included in the analysis, of whom 58 were randomized to immediate VA-ECMO and 59 to no immediate VA-ECMO. The composite primary end point occurred in 37 (63.8%) and 42 (71.2%) patients in the immediate VA-ECMO and the no early VA-ECMO groups, respectively (hazard ratio, 0.72 [95% CI, 0.46-1.12]; P=0.21). VA-ECMO was used in 23 (39%) of no early VA-ECMO patients. The 30-day incidence of resuscitated cardiac arrest (10.3.% versus 13.6%; risk difference, -3.2 [95% CI, -15.0 to 8.5]), all-cause mortality (50.0% versus 47.5%; risk difference, 2.5 [95% CI, -15.6 to 20.7]), serious adverse events (60.3% versus 61.0%; risk difference, -0.7 [95% CI, -18.4 to 17.0]), sepsis, pneumonia, stroke, leg ischemia, and bleeding was not statistically different between the immediate VA-ECMO and the no immediate VA-ECMO groups. CONCLUSIONS: Immediate implementation of VA-ECMO in patients with rapidly deteriorating or severe cardiogenic shock did not improve clinical outcomes compared with an early conservative strategy that permitted downstream use of VA-ECMO in case of worsening hemodynamic status. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02301819.

Venoarterial extracorporeal membrane oxygenation in patients with infarct-related cardiogenic shock: an individual patient data meta-analysis of randomised trials.

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used in patients with cardiogenic shock despite the lack of evidence from adequately powered randomised clinical trials. Three trials reported so far were underpowered to detect a survival benefit; we therefore conducted an individual patient-based meta-analysis to assess the effect of VA-ECMO on 30-day death rate. METHODS: Randomised clinical trials comparing early routine use of VA-ECMO versus optimal medical therapy alone in patients presenting with infarct-related cardiogenic shock were identified by searching MEDLINE, Cochrane Central Register of Controlled Trials, Embase, and trial registries until June 12, 2023. Trials were included if at least all-cause death rate 30 days after in-hospital randomisation was reported and trial investigators agreed to collaborate (ie, providing individual patient data). Odds ratios (ORs) as primary outcome measure were pooled using logistic regression models. This study is registered with PROSPERO (CRD42023431258). FINDINGS: Four trials (n=567 patients; 284 VA-ECMO, 283 control) were identified and included. Overall, there was no significant reduction of 30-day death rate with the early use of VA-ECMO (OR 0·93; 95% CI 0·66-1·29). Complication rates were higher with VA-ECMO for major bleeding (OR 2·44; 95% CI 1·55-3·84) and peripheral ischaemic vascular complications (OR 3·53; 95% CI 1·70-7·34). Prespecified subgroup analyses were consistent and did not show any benefit for VA-ECMO (pinteraction ≥0·079). INTERPRETATION: VA-ECMO did not reduce 30-day death rate compared with medical therapy alone in patients with infarct-related cardiogenic shock, and an increase in major bleeding and vascular complications was observed. A careful review of the indication for VA-ECMO in this setting is warranted. FUNDING: Foundation Institut für Herzinfarktforschung.

What is cardiogenic shock? New clinical criteria urgently needed.

PURPOSE OF REVIEW: Cardiogenic shock is a clinical syndrome with different causes and a complex pathophysiology. Recent evidence from clinical trials evokes the urgent need for redefining clinical diagnostic criteria to be compliant with the definition of cardiogenic shock and current diagnostic methods. RECENT FINDINGS: Conflicting results from randomized clinical trials investigating mechanical circulatory support in patients with cardiogenic shock have elicited several extremely important questions. At minimum, it is questionable whether survivors of cardiac arrest should be included in trials focused on cardiogenic shock. Moreover, considering the wide availability of ultrasound and hemodynamic monitors capable of arterial pressure analysis, the current clinical diagnostic criteria based on the presence of hypotension and hypoperfusion have become insufficient. As such, new clinical criteria for the diagnosis of cardiogenic shock should include evidence of low cardiac output and appropriate ventricular filling pressure. SUMMARY: Clinical diagnostic criteria for cardiogenic shock should be revised to better define cardiac pump failure as a primary cause of hemodynamic compromise.

Efficacy and Safety of Low-Dose Colchicine after Myocardial Infarction.

BACKGROUND: Experimental and clinical evidence supports the role of inflammation in atherosclerosis and its complications. Colchicine is an orally administered, potent antiinflammatory medication that is indicated for the treatment of gout and pericarditis. METHODS: We performed a randomized, double-blind trial involving patients recruited within 30 days after a myocardial infarction. The patients were randomly assigned to receive either low-dose colchicine (0.5 mg once daily) or placebo. The primary efficacy end point was a composite of death from cardiovascular causes, resuscitated cardiac arrest, myocardial infarction, stroke, or urgent hospitalization for angina leading to coronary revascularization. The components of the primary end point and safety were also assessed. RESULTS: A total of 4745 patients were enrolled; 2366 patients were assigned to the colchicine group, and 2379 to the placebo group. Patients were followed for a median of 22.6 months. The primary end point occurred in 5.5% of the patients in the colchicine group, as compared with 7.1% of those in the placebo group (hazard ratio, 0.77; 95% confidence interval [CI], 0.61 to 0.96; P = 0.02). The hazard ratios were 0.84 (95% CI, 0.46 to 1.52) for death from cardiovascular causes, 0.83 (95% CI, 0.25 to 2.73) for resuscitated cardiac arrest, 0.91 (95% CI, 0.68 to 1.21) for myocardial infarction, 0.26 (95% CI, 0.10 to 0.70) for stroke, and 0.50 (95% CI, 0.31 to 0.81) for urgent hospitalization for angina leading to coronary revascularization. Diarrhea was reported in 9.7% of the patients in the colchicine group and in 8.9% of those in the placebo group (P = 0.35). Pneumonia was reported as a serious adverse event in 0.9% of the patients in the colchicine group and in 0.4% of those in the placebo group (P = 0.03). CONCLUSIONS: Among patients with a recent myocardial infarction, colchicine at a dose of 0.5 mg daily led to a significantly lower risk of ischemic cardiovascular events than placebo. (Funded by the Government of Quebec and others; COLCOT ClinicalTrials.gov number, NCT02551094.).

Acute Severe Heart Failure Reduces Heart Rate Variability: An Experimental Study in a Porcine Model.

There are substantial differences in autonomic nervous system activation among heart (cardiac) failure (CF) patients. The effect of acute CF on autonomic function has not been well explored. The aim of our study was to assess the effect of experimental acute CF on heart rate variability (HRV). Twenty-four female pigs with a mean body weight of 45 kg were used. Acute severe CF was induced by global myocardial hypoxia. In each subject, two 5-min electrocardiogram segments were analyzed and compared: before the induction of myocardial hypoxia and >60 min after the development of severe CF. HRV was assessed by time-domain, frequency-domain and nonlinear analytic methods. The induction of acute CF led to a significant decrease in cardiac output, left ventricular ejection fraction and an increase in heart rate. The development of acute CF was associated with a significant reduction in the standard deviation of intervals between normal beats (50.8 [20.5−88.1] ms versus 5.9 [2.4−11.7] ms, p < 0.001). Uniform HRV reduction was also observed in other time-domain and major nonlinear analytic methods. Similarly, frequency-domain HRV parameters were significantly changed. Acute severe CF induced by global myocardial hypoxia is associated with a significant reduction in HRV.

Relation between Mid-Regional Pro-Adrenomedullin in Patients with Chronic Heart Failure and the Dose of Diuretics in 2-Year Follow-Up-Data from FAR NHL Registry.

Background and Objectives: The aim of this paper is to evaluate the impact of humoral substance mid-regional pro-adrenomedullin (MR-proADM) on the two-year survival of patients with chronic heart failure and relate it to the dosage of furosemide. Materials and Methods: The data is taken from the stable systolic heart failure (EF < 50%) FAR NHL registry (FARmacology and NeuroHumoraL activation). The primary endpoint at two-year follow-up was death, heart transplantation, or LVAD implantation. Results: A total of 1088 patients were enrolled in the FAR NHL registry; MR-proADM levels were available for 569 of them. The mean age was 65 years, and 81% were male. The aetiology of HF was ischemic heart disease in 53% and dilated cardiomyopathy in 41% of patients. The mean EF was 31 ± 9%. Statistically significant differences (p < 0.001) were obtained in several parameters: patients with higher MR-proADM levels were older, rated higher in NYHA class, suffered more often from lower limb oedema, and had more comorbidities such as hypertension, atrial fibrillation, diabetes, and renal impairment. MR-proADM level was related to furosemide dose. Patients taking higher doses of diuretics had higher MR-proADM levels. The mean MR-proADM level without furosemide (n = 122) was 0.62 (±0.55) nmol/L, with low dose (n = 113) 1−39 mg/day was 0.67 (±0.30) nmol/L, with mid dose (n = 202) 40−79 mg/day was 0.72 (±0.34) nmol/L, with high dose (n = 58) 80−119 mg/day was 0.85 (±0.40) nmol/L, and with maximum dose (n = 74) ≥120 mg/day was 1.07 (±0.76) nmol/L, p < 0.001. Patients with higher MR-proADM levels were more likely to achieve the primary endpoint at a two-year follow-up (p < 0.001) according to multivariant analysis. Conclusions: Elevated plasma MR-proADM levels in patients with chronic heart failure are associated with an increased risk of death and hospitalization. Higher MR-proADM levels in combination with increased use of loop diuretics reflect residual congestion and are associated with a higher risk of severe disease progression.

Biochemical markers for clinical monitoring of tissue perfusion.

The assessment and monitoring of the tissue perfusion is extremely important in critical conditions involving circulatory shock. There is a wide range of established methods for the assessment of cardiac output as a surrogate of oxygen delivery to the peripheral tissues. However, the evaluation of whether particular oxygen delivery is sufficient to ensure cellular metabolic demands is more challenging. In recent years, specific biochemical parameters have been described to indicate the status between tissue oxygen demands and supply. In this review, the authors summarize the application of some of these biochemical markers, including mixed venous oxygen saturation (SvO2), lactate, central venous-arterial carbon dioxide difference (PCO2 gap), and PCO2 gap/central arterial-to-venous oxygen difference (Ca-vO2) for hemodynamic assessment of tissue perfusion. The thorough monitoring of the adequacy of tissue perfusion and oxygen supply in critical conditions is essential for the selection of the most appropriate therapeutic strategy and it is associated with improved clinical outcomes.

Optimal use of lipid-lowering therapy after acute coronary syndromes: A Position Paper endorsed by the International Lipid Expert Panel (ILEP).

Atherosclerotic cardiovascular disease (ASCVD) and consequent acute coronary syndromes (ACS) are substantial contributors to morbidity and mortality across Europe. Much of these diseases burden is modifiable, in particular by lipid-lowering therapy (LLT). Current guidelines are based on the sound premise that with respect to low density lipoprotein cholesterol (LDL-C), "lower is better for longer", and the recent data have strongly emphasized the need of also "the earlier the better". In addition to statins, which have been available for several decades, the availability of ezetimibe and inhibitors of proprotein convertase subtilisin/kexin type 9 (PCSK9) are additional very effective approach to LLT, especially for those at very high and extremely high cardiovascular risk. LLT is initiated as a response to an individual's calculated risk of future ASCVD and is intensified over time in order to meet treatment goals. However, in real-life clinical practice goals are not met in a substantial proportion of patients. This Position Paper complements existing guidelines on the management of lipids in patients following ACS. Bearing in mind the very high risk of further events in ACS, we propose practical solutions focusing on immediate combination therapy in strict clinical scenarios, to improve access and adherence to LLT in these patients. We also define an 'Extremely High Risk' group of individuals following ACS, completing the attempt made in the recent European guidelines, and suggest mechanisms to urgently address lipid-medicated cardiovascular risk in these patients.

Bypassing out-of-hospital cardiac arrest patients to a regional cardiac center: Impact on hemodynamic parameters and outcomes.

INTRODUCTION: Current guidelines recommend systematic care for patients who experience out-of-hospital cardiac arrest (OHCA) and the development of cardiac arrest centers (CACs). However, data regarding prolonged transport time of these often hemodynamically unstable patients are limited. METHODS: Data from a prospective OHCA registry of a regional CAC collected between 2013 and 2017, when all OHCA patients from the district were required to be transferred directly to the CAC, were analyzed. Patients were divided into two subgroups: CAC, when the CAC was the nearest hospital; and bypass, when OHCA occurred in a region of another local hospital but the subject was transferred directly to the CAC (7 hospitals in the district). Data included transport time, baseline characteristics, hemodynamic and laboratory parameters on admission (systolic blood pressure, lactate, pH, oxygen saturation, body temperature, and initial doses of vasopressors and inotropes), and final outcomes (30-day in-hospital mortality, intensive care unit stay, days on artificial ventilation, and cerebral performance capacity at 1 year). RESULTS: A total of 258 subjects experienced OHCA in the study period; however, 27 were excluded due to insufficient data and 17 for secondary transfer to CAC. As such, 214 patients were analyzed, 111 in the CAC group and 103 in the bypass group. The median transport time was significantly longer for the bypass group than the CAC group (40.5 min [IQR 28.3-55.0 min] versus 20.0 min [IQR 13.0-34.0], respectively; p˂0.0001). There were no differences in 30-day in-hospital mortality, 1-year neurological outcome, or median length of mechanical ventilation. There were no differences in baseline characteristics, initial hemodynamic parameters on admission, catecholamine dosage(s). CONCLUSION: Individuals who experienced OHCA and taken to a CAC incurred significantly prolonged transport times; however, hemodynamic parameters and/or outcomes were not affected. These findings shows the safety of bypassing local hospitals for a CAC.

Effect of Alirocumab on Mortality After Acute Coronary Syndromes.

BACKGROUND: Previous trials of PCSK9 (proprotein convertase subtilisin-kexin type 9) inhibitors demonstrated reductions in major adverse cardiovascular events, but not death. We assessed the effects of alirocumab on death after index acute coronary syndrome. METHODS: ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) was a double-blind, randomized comparison of alirocumab or placebo in 18 924 patients who had an ACS 1 to 12 months previously and elevated atherogenic lipoproteins despite intensive statin therapy. Alirocumab dose was blindly titrated to target achieved low-density lipoprotein cholesterol (LDL-C) between 25 and 50 mg/dL. We examined the effects of treatment on all-cause death and its components, cardiovascular and noncardiovascular death, with log-rank testing. Joint semiparametric models tested associations between nonfatal cardiovascular events and cardiovascular or noncardiovascular death. RESULTS: Median follow-up was 2.8 years. Death occurred in 334 (3.5%) and 392 (4.1%) patients, respectively, in the alirocumab and placebo groups (hazard ratio [HR], 0.85; 95% CI, 0.73 to 0.98; P=0.03, nominal P value). This resulted from nonsignificantly fewer cardiovascular (240 [2.5%] vs 271 [2.9%]; HR, 0.88; 95% CI, 0.74 to 1.05; P=0.15) and noncardiovascular (94 [1.0%] vs 121 [1.3%]; HR, 0.77; 95% CI, 0.59 to 1.01; P=0.06) deaths with alirocumab. In a prespecified analysis of 8242 patients eligible for ≥3 years follow-up, alirocumab reduced death (HR, 0.78; 95% CI, 0.65 to 0.94; P=0.01). Patients with nonfatal cardiovascular events were at increased risk for cardiovascular and noncardiovascular deaths ( P<0.0001 for the associations). Alirocumab reduced total nonfatal cardiovascular events ( P<0.001) and thereby may have attenuated the number of cardiovascular and noncardiovascular deaths. A post hoc analysis found that, compared to patients with lower LDL-C, patients with baseline LDL-C ≥100 mg/dL (2.59 mmol/L) had a greater absolute risk of death and a larger mortality benefit from alirocumab (HR, 0.71; 95% CI, 0.56 to 0.90; Pinteraction=0.007). In the alirocumab group, all-cause death declined with achieved LDL-C at 4 months of treatment, to a level of approximately 30 mg/dL (adjusted P=0.017 for linear trend). CONCLUSIONS: Alirocumab added to intensive statin therapy has the potential to reduce death after acute coronary syndrome, particularly if treatment is maintained for ≥3 years, if baseline LDL-C is ≥100 mg/dL, or if achieved LDL-C is low. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01663402.

Effects of the chymase inhibitor fulacimstat on adverse cardiac remodeling after acute myocardial infarction-Results of the Chymase Inhibitor in Adverse Remodeling after Myocardial Infarction (CHIARA MIA) 2 trial.

BACKGROUND: Adverse cardiac remodeling is a major risk factor for the development of post myocardial infarction (MI) heart failure (HF). This study investigates the effects of the chymase inhibitor fulacimstat on adverse cardiac remodeling after acute ST-segment-elevation myocardial infarction (STEMI). METHODS: In this double-blind, randomized, placebo-controlled trial patients with first STEMI were eligible. To preferentially enrich patients at high risk of adverse remodeling, main inclusion criteria were a left-ventricular ejection fraction (LVEF) ≤45% and an infarct size >10% on day 5 to 9 post MI as measured by cardiac MRI. Patients were then randomized to 6 months treatment with either 25 mg fulacimstat (n = 54) or placebo (n = 53) twice daily on top of standard of care starting day 6 to 12 post MI. The changes in LVEF, LV end-diastolic volume index (LVEDVI), and LV end-systolic volume index (LVESVI) from baseline to 6 months were analyzed by a central blinded cardiac MRI core laboratory. RESULTS: Fulacimstat was safe and well tolerated and achieved mean total trough concentrations that were approximately tenfold higher than those predicted to be required for minimal therapeutic activity. Comparable changes in LVEF (fulacimstat: 3.5% ±â€¯5.4%, placebo: 4.0% ±â€¯5.0%, P = .69), LVEDVI (fulacimstat: 7.3 ±â€¯13.3 mL/m2, placebo: 5.1 ±â€¯18.9 mL/m2, P = .54), and LVESVI (fulacimstat: 2.3 ±â€¯11.2 mL/m2, placebo: 0.6 ±â€¯14.8 mL/m2, P = .56) were observed in both treatment arms. CONCLUSION: Fulacimstat was safe and well tolerated in patients with left-ventricular dysfunction (LVD) after first STEMI but had no effect on cardiac remodeling.

Increasing venoarterial extracorporeal membrane oxygenation flow puts higher demands on left ventricular work in a porcine model of chronic heart failure.

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (VA ECMO) is widely used in the treatment of circulatory failure, but repeatedly, its negative effects on the left ventricle (LV) have been observed. The purpose of this study is to assess the influence of increasing extracorporeal blood flow (EBF) on LV performance during VA ECMO therapy of decompensated chronic heart failure. METHODS: A porcine model of low-output chronic heart failure was developed by long-term fast cardiac pacing. Subsequently, under total anesthesia and artificial ventilation, VA ECMO was introduced to a total of five swine with profound signs of chronic cardiac decompensation. LV performance and organ specific parameters were recorded at different levels of EBF using a pulmonary artery catheter, a pressure-volume loop catheter positioned in the LV, and arterial flow probes on systemic arteries. RESULTS: Tachycardia-induced cardiomyopathy led to decompensated chronic heart failure with mean cardiac output of 2.9 ± 0.4 L/min, severe LV dilation, and systemic hypoperfusion. By increasing the EBF from minimal flow to 5 L/min, we observed a gradual increase of LV peak pressure from 49 ± 15 to 73 ± 11 mmHg (P = 0.001) and an improvement in organ perfusion. On the other hand, cardiac performance parameters revealed higher demands put on LV function: LV end-diastolic pressure increased from 7 ± 2 to 15 ± 3 mmHg, end-diastolic volume increased from 189 ± 26 to 218 ± 30 mL, end-systolic volume increased from 139 ± 17 to 167 ± 15 mL (all P < 0.001), and stroke work increased from 1434 ± 941 to 1892 ± 1036 mmHg*mL (P < 0.05). LV ejection fraction and isovolumetric contractility index did not change significantly. CONCLUSIONS: In decompensated chronic heart failure, excessive VA ECMO flow increases demands and has negative effects on the workload of LV. To protect the myocardium from harm, VA ECMO flow should be adjusted with respect to not only systemic perfusion, but also to LV parameters.

LUCAS II Device for Cardiopulmonary Resuscitation in a Nonselective Out-of-Hospital Cardiac Arrest Population Leads to Worse 30-Day Survival Rate Than Manual Chest Compressions.

BACKGROUND: The LUCAS (Lund University Cardiopulmonary Assist System; Physio-Control Inc./Jolife AB, Lund, Sweden) was developed for automatic chest compressions during cardiopulmonary resuscitation (CPR). Evidence on the use of this device in out-of-hospital cardiac arrest (OHCA) suggests that it should not be used routinely because it has no superior effects. OBJECTIVE: The aim of this study was to compare the effect of CPR for OHCA with and without LUCAS via a regional nonurban emergency medical service (EMS) physician-present prehospital medical system. METHODS: We analyzed a prospective registry of all consecutive OHCA patients in four EMS stations. Two of them used a LUCAS device in all CPR, and the EMS crews in the other two stations used manual CPR. Individuals with contraindication to LUCAS or with EMS-witnessed arrest were excluded. RESULTS: Data from 278 patients were included in the analysis, 144 with LUCAS and 134 with manual CPR. There were more witnessed arrests in the LUCAS group (79.17% vs. 64.18%; p = 0.0074) and patients in the LUCAS group were older (p = 0.03). We found no significant difference in return of spontaneous circulation (30.6% in non-LUCAS vs. 25% in LUCAS; p = 0.35). In the LUCAS group, we observed significantly more conversions from nonshockable to shockable rhythm (20.7% vs. 10.10%; p = 0.04). The 30-day survival rate was significantly lower in the LUCAS group (5.07% vs. 16.31% in the non-LUCAS group; p = 0.044). At 180-day follow-up, we observed no significant difference (5.45% in non-LUCAS vs. 9.42% in LUCAS; p = 0.25). CONCLUSIONS: Use of the LUCAS system decreased survival rate in OHCA patients. Significantly higher 30-day mortality was seen in LUCAS-treated patients.

Continual measurement of arterial dP/dtmax enables minimally invasive monitoring of left ventricular contractility in patients with acute heart failure.

BACKGROUND: Continuous, reliable evaluation of left ventricular (LV) contractile function in patients with advanced heart failure requiring intensive care remains challenging. Continual monitoring of dP/dtmax from the arterial line has recently become available in hemodynamic monitoring. However, the relationship between arterial dP/dtmax and LV dP/dtmax remains unclear. This study aimed to determine the relationship between arterial dP/dtmax and LV dP/dtmax assessed using echocardiography in patients with acute heart failure. METHODS: Forty-eight patients (mean age 70.4 years [65% male]) with acute heart failure requiring intensive care and hemodynamic monitoring were recruited. Hemodynamic variables, including arterial dP/dtmax, were continually monitored using arterial line pressure waveform analysis. LV dP/dtmax was assessed using continuous-wave Doppler analysis of mitral regurgitation flow. RESULTS: Values from continual arterial dP/dtmax monitoring were significantly correlated with LV dP/dtmax assessed using echocardiography (r = 0.70 [95% confidence interval (CI) 0.51-0.82]; P < 0.0001). Linear regression analysis revealed that LV dP/dtmax = 1.25 × (arterial dP/dtmax) (P < 0.0001). Arterial dP/dtmax was also significantly correlated with stroke volume (SV) (r = 0.63; P < 0.0001) and cardiac output (CO) (r = 0.42; P = 0.0289). In contrast, arterial dP/dtmax was not correlated with SV variation, dynamic arterial elastance, heart rate, systemic vascular resistance (SVR), or mean arterial pressure. Markedly stronger agreement between arterial and LV dP/dtmax was observed in subgroups with higher SVR (N = 28; r = 0.91; P <  0.0001), lower CO (N = 26; r = 0.81; P <  0.0001), and lower SV (N = 25; r = 0.60; P = 0.0014). A weak correlation was observed in the subjects with lower SVR (N = 20; r = 0.61; P = 0.0004); in the subgroups with higher CO (N = 22) and higher SV (N = 23), no significant correlation was found. CONCLUSION: Our results suggest that in patients with acute heart failure requiring intensive care with an arterial line, continuous calculation of arterial dP/dtmax may be used for monitoring LV contractility, especially in those with higher SVR, lower CO, and lower SV, such as in patients experiencing cardiogenic shock. On the other hand, there was only a weak or no significant correlation in the subgroups with higher CO, higher SV, and lower SVR.

Association of neuron-specific enolase values with outcomes in cardiac arrest survivors is dependent on the time of sample collection.

BACKGROUND: Despite marked advances in intensive cardiology care, current options for outcome prediction in cardiac arrest survivors remain significantly limited. The aim of our study was, therefore, to compare the day-specific association of neuron-specific enolase (NSE) with outcomes in out-of-hospital cardiac arrest (OHCA) survivors treated with hypothermia. METHODS: Eligible patients were OHCA survivors treated with targeted temperature management at 33 °C for 24 h using an endovascular device. Blood samples for NSE levels measurement were drawn on days 1, 2, 3, and 4 after hospital admission. Thirty-day neurological outcomes according to the Cerebral Performance Category (CPC) scale and 12-month mortality were evaluated as clinical end points. RESULTS: A total of 153 cardiac arrest survivors (mean age 64.2 years) were enrolled in the present study. Using ROC analysis, optimal cutoff values of NSE for prediction of CPC 3-5 score on specific days were determined as: day 1 > 20.4 mcg/L (sensitivity 63.3%; specificity 82.1%; P = 0.002); day 2 > 29.0 mcg/L (72.5%; 94.4%; P < 0.001); and day 3 > 20.7 mcg/L (94.4%; 86.7%; P < 0.001). The highest predictive value, however, was observed on day 4 > 19.4 mcg/L (93.5%; 91.0%; P < 0.001); NSE value >50.2 mcg/L at day 4 was associated with poor outcome with 100% specificity and 42% sensitivity. Moreover, NSE levels measured on all individual days also predicted 12-month mortality (P < 0.001); the highest predictive value for death was observed on day 3 > 18.1 mcg/L (85.3%; 72.0%; P < 0.001). Significant association with prognosis was found also for changes in NSE at different time points. An NSE level on day 4 > 20.0 mcg/L, together with a change > 0.0 mcg/L from day 3 to day 4, predicted poor outcome (CPC 3-5) with 100% specificity and 73% sensitivity. CONCLUSIONS: Our results suggest that NSE levels are a useful tool for predicting 30-day neurological outcome and long-term mortality in OHCA survivors treated with targeted temperature management at 33 °C. The highest associations of NSE with outcomes were observed on day 4 and day 3 after cardiac arrest.

Ischemic Postconditioning and Nitric Oxide Administration Failed to Confer Protective Effects in a Porcine Model of Extracorporeal Cardiopulmonary Resuscitation.

The protective effects of ischemic postconditioning (IPC) and nitric oxide (NO) administration have been demonstrated in several ischemic scenarios. However, current evidence regarding the effect of IPC and NO in extracorporeal cardiopulmonary resuscitation remains lacking. Fifteen female swine (body weight 45 kg) underwent veno-arterial extracorporeal membrane oxygenation (ECMO) implantation; cardiac arrest-ventricular fibrillation was induced by rapid ventricular pacing. After 20 min of cardiac arrest, blood flow was restored by increasing the ECMO flow rate to 4.5 L/min. The animals (five per group) were then randomly assigned to receive IPC (three cycles of 3 min ischemia and reperfusion), NO (80 ppm via oxygenator), or mild hypothermia (HT; 33.0°C). Cerebral oximetry and aortic blood pressure were monitored continuously. After 90 min of reperfusion, blood samples were drawn for the measurement of troponin I, myoglobin, creatine-phosphokinase, alanine aminotransferase, neuron-specific enolase, cystatin C, and reactive oxygen metabolite (ROM) levels. Significantly higher blood pressure and cerebral oxygen saturation values were observed in the HT group compared with the IPC and NO groups (P < 0.05). The levels of troponin I, myoglobin, creatine phosphokinase, and alanine aminotransferase were significantly lower in the HT group (P < 0.05); levels of neuron-specific enolase, cystatin C, and ROM were not significantly different. IPC and NO were comparable in all monitored parameters. The results of the present study indicate that IPC and NO administration are not superior interventions to HT for the maintenance of blood pressure, cerebral oxygenation, organ protection, and suppression of oxidative stress following extracorporeal cardiopulmonary resuscitation.

Inducibility of ventricular fibrillation during mild therapeutic hypothermia: electrophysiological study in a swine model.

INTRODUCTION: Mild therapeutic hypothermia (MTH) is being used after cardiac arrest for its expected improvement in neurological outcome. Safety of MTH concerning inducibility of malignant arrhythmias has not been satisfactorily demonstrated. This study compares inducibility of ventricular fibrillation (VF) before and after induction of MTH in a whole body swine model and evaluates possible interaction with changing potassium plasma levels. METHODS: The extracorporeal cooling was introduced in fully anesthetized swine (n = 6) to provide MTH. Inducibility of VF was studied by programmed ventricular stimulation three times in each animal under the following: during normothermia (NT), after reaching the core temperature of 32°C (HT) and after another 60 minutes of stable hypothermia (HT60). Inducibility of VF, effective refractory period of the ventricles (ERP), QTc interval and potassium plasma levels were measured. RESULTS: Starting at normothermia of 38.7 (IQR 38.2; 39.8)°C, HT was achieved within 54 (39; 59) minutes and the core temperature was further maintained constant. Overall, the inducibility of VF was 100% (18/18 attempts) at NT, 83% (15/18) after reaching HT (P = 0.23) and 39% (7/18) at HT60 (P = 0.0001) using the same protocol. Similarly, ERP prolonged from 140 (130; 150) ms at NT to 206 (190; 220) ms when reaching HT (P < 0.001) and remained 206 (193; 220) ms at HT60. QTc interval was inversely proportional to the core temperature and extended from 376 (362; 395) at NT to 570 (545; 599) ms at HT. Potassium plasma level changed spontaneously: decreased during cooling from 4.1 (3.9; 4.8) to 3.7 (3.4; 4.1) mmol/L at HT (P < 0.01), then began to increase and returned to baseline level at HT60 (4.6 (4.4; 5.0) mmol/L, P = NS). CONCLUSIONS: According to our swine model, MTH does not increase the risk of VF induction by ventricular pacing in healthy hearts. Moreover, when combined with normokalemia, MTH exerts an antiarrhythmic effect despite prolonged QTc interval.

Increasing venoarterial extracorporeal membrane oxygenation flow negatively affects left ventricular performance in a porcine model of cardiogenic shock.

BACKGROUND: The aim of this study was to assess the relationship between extracorporeal blood flow (EBF) and left ventricular (LV) performance during venoarterial extracorporeal membrane oxygenation (VA ECMO) therapy. METHODS: Five swine (body weight 45 kg) underwent VA ECMO implantation under general anesthesia and artificial ventilation. Subsequently, acute cardiogenic shock with signs of tissue hypoxia was induced. Hemodynamic and cardiac performance parameters were then measured at different levels of EBF (ranging from 1 to 5 L/min) using arterial and venous catheters, a pulmonary artery catheter and a pressure-volume loop catheter introduced into the left ventricle. RESULTS: Myocardial hypoxia resulted in a decline in mean (±SEM) cardiac output to 2.8 ± 0.3 L/min and systolic blood pressure (SBP) to 60 ± 7 mmHg. With an increase in EBF from 1 to 5 L/min, SBP increased to 97 ± 8 mmHg (P < 0.001); however, increasing EBF from 1 to 5 L/min significantly negatively influences several cardiac performance parameters: cardiac output decreased form 2.8 ± 0.3 L/min to 1.86 ± 0.53 L/min (P < 0.001), LV end-systolic volume increased from 64 ± 11 mL to 83 ± 14 mL (P < 0.001), LV stroke volume decreased from 48 ± 9 mL to 40 ± 8 mL (P = 0.045), LV ejection fraction decreased from 43 ± 3 % to 32 ± 3 % (P < 0.001) and stroke work increased from 2096 ± 342 mmHg mL to 3031 ± 404 mmHg mL (P < 0.001). LV end-diastolic pressure and volume were not significantly affected. CONCLUSIONS: The results of the present study indicate that higher levels of VA ECMO blood flow in cardiogenic shock may negatively affect LV function. Therefore, it appears that to mitigate negative effects on LV function, optimal VA ECMO blood flow should be set as low as possible to allow adequate tissue perfusion.

Statins for acute coronary syndrome.

BACKGROUND: The early period following the onset of acute coronary syndrome (ACS) represents a critical stage of coronary heart disease, with a high risk of recurrent events and deaths. The short-term effects of early treatment with statins on patient-relevant outcomes in patients suffering from ACS are unclear. This is an update of a review previously published in 2011. OBJECTIVES: To assess the effects, both harms and benefits, of early administered statins in patients with ACS, in terms of mortality and cardiovascular events. SEARCH METHODS: We updated the searches of CENTRAL (2013, Issue 3), MEDLINE (Ovid) (1946 to April Week 1 2013), EMBASE (Ovid) (1947 to 2013 Week 14), and CINAHL (EBSCO) (1938 to 2013) on 12 April 2013. We applied no language restrictions. We supplemented the search by contacting experts in the field, by reviewing the reference lists of reviews and editorials on the topic, and by searching trial registries. SELECTION CRITERIA: Randomized controlled trials (RCTs) comparing statins with placebo or usual care, with initiation of statin therapy within 14 days following the onset of ACS, follow-up of at least 30 days, and reporting at least one clinical outcome. DATA COLLECTION AND ANALYSIS: Two authors independently assessed risk of bias and extracted data. We calculated risk ratios (RRs) for all outcomes in the treatment and control groups and pooled data using random-effects models. MAIN RESULTS: Eighteen studies (14,303 patients) compared early statin treatment versus placebo or no treatment in patients with ACS. The new search did not identify any new studies for inclusion. There were some concerns about risk of bias and imprecision of summary estimates. Based on moderate quality evidence, early statin therapy did not decrease the combined primary outcome of death, non-fatal myocardial infarction, and stroke at one month (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.80 to 1.08) or four months (RR 0.93, 95% CI 0.81 to 1.06) of follow-up when compared to placebo or no treatment. There were no statistically significant risk reductions from statins for total death, total myocardial infarction, total stroke, cardiovascular death, revascularization procedures, and acute heart failure at one month or at four months, although there were favorable trends related to statin use for each of these endpoints. Moderate quality evidence suggests that the incidence of unstable angina was significantly reduced at four months following ACS (RR 0.76, 95% CI 0.59 to 0.96). There were nine individuals with myopathy (elevated creatinine kinase levels more than 10 times the upper limit of normal) in statin-treated patients (0.13%) versus one (0.015%) in the control groups. Serious muscle toxicity was mostly limited to patients treated with simvastatin 80 mg. AUTHORS' CONCLUSIONS: Based on moderate quality evidence, due to concerns about risk of bias and imprecision, initiation of statin therapy within 14 days following ACS does not reduce death, myocardial infarction, or stroke up to four months, but reduces the occurrence of unstable angina at four months following ACS. Serious side effects were rare.