German Cardiac Arrest Registry (G-CAR)-results of the pilot phase.

BACKGROUND: In Europe, more than 300,000 persons per year experience out-of-hospital cardiac arrest (OHCA). Despite medical progress, only few patients survive with good neurological outcome. For many issues, evidence from randomized trials is scarce. OHCA often occurs for cardiac causes. Therefore, we established the national, prospective, multicentre German Cardiac Arrest Registry (G-CAR). Herein, we describe the first results of the pilot phase. RESULTS: Over a period of 16 months, 15 centres included 559 consecutive OHCA patients aged ≥ 18 years. The median age of the patients was 66 years (interquartile range 57;75). Layperson resuscitation was performed in 60.5% of all OHCA cases which were not observed by emergency medical services. The initial rhythm was shockable in 46.4%, and 29.1% of patients had ongoing CPR on hospital admission. Main presumed causes of OHCA were acute coronary syndromes (ACS) and/or cardiogenic shock in 54.8%, with ST-elevation myocardial infarction being the most common aetiology (34.6%). In total, 62.9% of the patients underwent coronary angiography; percutaneous coronary intervention (PCI) was performed in 61.4%. Targeted temperature management was performed in 44.5%. Overall in-hospital mortality was 70.5%, with anoxic brain damage being the main presumed cause of death (38.8%). Extracorporeal cardiopulmonary resuscitation (eCPR) was performed in 11.0%. In these patients, the in-hospital mortality rate was 85.2%. CONCLUSIONS: G-CAR is a multicentre German registry for adult OHCA patients with a focus on cardiac and interventional treatment aspects. The results of the 16-month pilot phase are shown herein. In parallel with further analyses, scaling up of G-CAR to a national level is envisaged. Trial registration ClinicalTrials.gov identifier: NCT05142124.

Accredited cardiac arrest centers facilitate eCPR and improve neurological outcome.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) remains a frequent medical emergency with low survival rates even after a return of spontaneous circulation (ROSC). Growing evidence supports formation of dedicated teams in scenarios like cardiogenic shock to improve prognosis. Thus, the European Resuscitation Council (ERC) recommended introduction of Cardiac Arrest Centers (CAC) in their 2015 guidelines. Here, we aimed to elucidate the effects of newly introduced CACs in Germany regarding survival rate and neurological outcome. METHODS: A multicenter retrospective observational cohort study was performed at three university hospitals and outcomes after OHCA were compared before and after CAC accreditation. Primary outcomes were survival until discharge and favorable neurological status (CPC 1 or 2) at discharge. RESULTS: In total 784 patients (368 before and 416 after CAC accreditation) were analyzed. Rates of immediate percutaneous coronary intervention (40 vs. 52%, p = 0.01) and implementation of extracorporeal CPR (8 vs. 13%, p < 0.05) increased after CAC accreditation. Likelihood of favorable neurological status at discharge was higher after CAC accreditation (71 vs. 87%, p < 0.01), whereas overall survival remained similar (35 vs. 35%, p > 0.99). CONCLUSION: CAC accreditation is linked to higher rates of favorable neurological outcome and unchanged overall survival.

Outcome of Patients Managed by Percutaneous Left Ventricular Assist Device Implantation During On-Hours and Off-Hours.

Percutaneous left ventricular assist devices (pVADs) may be used in patients with cardiogenic shock (CS) to stabilize hemodynamics and maintain sufficient end-organ perfusion. Vascular complications are commonly observed in patients with pVAD support. We aimed to assess the relationship between pVAD implantation time and access-site complication rates. This retrospective observational study included all patients who underwent pVAD insertion for the treatment of CS at our university hospital between 2014 and 2021 (n = 224). Depending on the pVAD insertion time, the patients were assigned to the on-hours (n = 120) or off-hours group (n = 104). Both groups had comparable baseline characteristics and comorbidities. The rate of access-site-related complications was higher in the off-hours group than in the on-hours group (26% vs. 10%, p = 0.002). Premature discontinuation of pVAD support to prevent limb ischemia or manage access-site bleeding was required more often in the off-hours group than in the on-hours group (14% vs. 5%, p = 0.016). Pre-existing peripheral artery disease and implantation time off-hours were independent predictors for access-siterelated vascular complications. In conclusion, patients with CS in whom pVAD was inserted during off-hours had higher rates of access-site-related complications and premature discontinuation of pVAD support than those in whom pVAD was inserted during on-hours.

Evaluation of risk factors for cytomegalovirus DNAemia after end of regular prophylaxis after heart transplantation.

BACKGROUND: Cytomegalovirus (CMV) infections after heart transplantation (HTx) can cause cardiac allograft vasculopathy. Consequently, monitoring and prophylaxis for cytomegalovirus deoxyribonucleic acid (CMV-DNAemia) within the first weeks after HTx is recommended. METHODS: All patients who underwent HTx between September 2010 and 2021 surviving the first 90 days (n = 196) were retrospectively reviewed. The patients were divided on the prevalence of CMV-DNAemia during the first postoperative year after the end of the prophylaxis. A total of n = 35 (20.1%) developed CMV-DNAemia (CMV group) and were compared to patients without CMV-DNAemia (controls, n = 139). The remaining patients (n = 22) were excluded due to incomplete data. RESULTS: Positive donors and negative recipients (D+/R-) and negative donors and positive recipients (D-/R+) serology was significantly increased and D-/R- decreased in the CMV group (p < .01). Furthermore, the mean age was 57.7 ± 8.7 years but only 53.6 ± 10.0 years for controls (p = .03). Additionally, the intensive care unit (p = .02) and total hospital stay (p = .03) after HTx were approximately 50% longer. Interestingly, the incidence of CMV-DNAemia during prophylaxis was only numerically increased in the CMV group (5.7%, respectively, 0.7%, p = .10), the same effect was also observed for postoperative infections. Multivariate analyses confirmed that D+/R- and D-/R+ CMV immunoglobulin G match were independent risk factors for postprophylaxis CMV-DNAemia. CONCLUSION: Our data should raise awareness of CMV-DNAemia after the termination of regular prophylaxis, as this affects one in five HTx patients. Especially old recipients as well as D+/R- and D-/R+ serology share an elevated risk of late CMV-DNAemia. For these patients, prolongation, or repetition of CMV prophylaxis, including antiviral drugs and CMV immunoglobulins, may be considered.

Cocoa flavanols improve peakVO2 and exercise capacity in a randomized double blinded clinical trial in healthy elderly people.

Background: Loss of functional capacity is one of the hallmarks in cardiovascular aging. Cocoa flavanols (CF) exert favorable effects on endothelial function, blood pressure, and inflammation. These cardiovascular health markers worsen with increasing age and limit functional exercise capacity. Aim: To investigate the effect of CF on cardiorespiratory-fitness in healthy elderly people. Methods: In a randomized, double-masked, placebo-controlled, parallel-group dietary intervention trial, 68 healthy elderly people (55-79 years, 28 female) received either 500 mg of CF or a nutrient-matched control capsule twice a day for 30 days. Primary endpoint was defined as peak oxygen consumption (VO2) in a cardiopulmonary exercise test (CPET). Secondary endpoints were oxygen pulse (VO2 per heart rate (HR)), resting blood pressure (BP), and resting vascular function. Results: After 30 days of CF intake peakVO2 increased by 190 ml min-1 (95% CI 1-371 ml min-1) and peakVO2 per kg by 2.5 ml (min kg)-1 (95% CI 0.30-4.2 ml (min kg)-1). O2-pulse increased by 1.7 ml (95% CI 0.29-3.2 ml) and max exercise capacity by 9.6 W (95% CI 2.1-17.7 W). CF decreased resting systolic and diastolic BP by 5.4 mmHg (95% CI -10.7 to -0.1 mmHg) and 2.9 mmHg (95% CI -5.5 to -0.4 mmHg), respectively. Flow-mediated vasodilation (FMD) increased by an absolute 1.3% (95% CI 0.76-1.79%) in the CF group. Indexes of pulmonary function were not affected. No changes for primary and secondary endpoints were detected in control. Conclusion: CF substantially improve markers of cardiorespiratory fitness in healthy elderly humans highlighting their potential to preserve cardiovascular health with increasing age.

Lactate versus Phosphate as Biomarkers to Aid Mechanical Circulatory Support Decisions in Patients with Out-of-Hospital Cardiac Arrest and Return of Spontaneous Circulation.

AIMS: Identifying patients who may benefit from mechanical circulatory support (MCS) after out-of-hospital cardiac arrest (OHCA) and return of spontaneous circulation (ROSC) remains challenging; thus, a search for helpful biomarkers is warranted. We aimed to evaluate phosphate and lactate levels on admission regarding their associations with survival with and without MCS. METHODS: In 224 OHCA patients who achieved ROSC, the initial phosphate and lactate levels were investigated to discriminate in-hospital mortality by receiver operating characteristic (ROC) curves. According to the Youden Index (YI) from the respective ROC, the groups were risk stratified by both biomarkers, and 30-day mortality was analyzed in patients with and without MCS. RESULTS: Within the entire collective, MCS was not associated with a better chance of survival. Both phosphate and lactate level elevations showed good yet comparable discriminations to predict mortality (areas under the curve: 0.80 vs. 0.79, p = 0.74). In patients with initial phosphate values > 2.2 mmol/L (>YI), 30-day mortality within the MCS cohort was lower (HR 2.3, 95% CI: 1.4-3.7; p = 0.0037). In patients with lower phosphate levels and groups stratified by lactate, 30-day mortality was similar in patients with and without MCS. CONCLUSIONS: We found a significant association between survival and MCS therapy in patients with phosphate levels above 2.2 mmol/L (Youden Index), and a similar discrimination of patient overall survival by lactate and phosphate. Prospective studies should assess the possible independent prognostic value of phosphate and its clearance for MCS efficiency.

Elevated Initial Serum Phosphate Levels Predict Higher Mortality and Impaired Neurological Outcome in Cardiac Arrest Patients with Return of Spontaneous Circulation.

Purpose: Although a moderate proportion of cardiac arrest (CA) patients achieve a return of spontaneous circulation (ROSC), few survive to discharge, mostly with poor neurological development. As serum phosphate levels were described as elevated after cardiopulmonary resuscitation (CPR), we asked whether these elevations would predict a higher risk of mortality and impaired neurological outcome in CA patients following ROSC. Methods: Initial serum phosphate levels, survival, and neurologic status at discharge of 488 non-traumatic CA patients treated at a single German hospital after achieving ROSC were analyzed. The cut-off value of phosphate for mortality prediction was determined using the receiver operator characteristic (ROC) curve, and patients were divided accordingly for comparison. Results were validated by analyzing phosphate levels in a multi-centric cohort containing 3299 CA patients from the eICU database of the United States. Results: In the German cohort, ROC analysis showed a 90% specificity for phosphate levels >2.7 mmol/L to predict mortality (AUC: 0.76, p < 0.0001), and phosphate level elevations were associated with higher in-hospital mortality (crude odds ratio 3.04, 95% CI 2.32 to 4.08). Patients with initial phosphate levels >2.7 mmol/L had significantly higher mortality in both analyzed collectives (p < 0.0001). Similarly, patients from the German cohort who initially had higher phosphate levels also showed a higher proportion of impaired neurological status at discharge and morphological signs of brain injury. Conclusions: In CA patients following ROSC, initial serum phosphate levels >2.7 mmol/L predict higher mortality and impaired neurological outcome. Our data suggests that phosphate determination might improve the preciseness of the overall and neurologic prognostication in patients after CPR following ROSC.

Donor Noradrenaline Support Is Not Associated with Decreased Survival in Heart Transplant Recipients.

Objective: Although the application of higher doses of norepinephrine (NE) in potential organ donors is a frequent reason for heart decline, its associations with outcomes after heart transplantation (HTx) are discussed controversially. Therefore, we aimed to explore donor NE support's potential impact on outcomes in our single-center heart transplant cohort. Methods: All patients who had undergone HTx in our center between September 2010 and April 2022 (n = 241) were screened for eligibility. From those, all patients with complete data on donor NE support (n = 238) were included. Recipients were divided into three groups according to their donor NE support: without support (n = 26), with low support of 0.01−0.2 µg/kg/min (n = 132), and with high support of > 0.2 µg/kg/min (n = 80). Receiver operating characteristics (ROC) and Kaplan Meier analysis was used to investigate the association of donor NE support and mortality after heart transplantation. Recipient and donor variables, including peri- and postoperative characteristics, were reviewed and compared. Results: NE support in donors ranged between 0 and 2.94 µg/kg/min (median 0.13 µg/kg/min, IQR 0.05−0.26 µg/kg/min). No association between donor NE support and mortality after HTx was observed (AUC for overall survival 0.494). Neither Kaplan-Meier analysis in survival up to 5 years after transplantation (Log Rank p = 0.284) nor group comparisons showed significant differences between the groups. With few exceptions, baseline characteristics in recipients and donors were comparable between the groups. Regarding peri- and postoperative parameters, increasing donor NE support was associated with a longer duration of mechanical ventilation (68 h and 95 h vs. 47 h), longer postoperative IMC/ICU stay (14 vs. 15 vs. 19 days), and a higher need for mechanical life support post-HTx (26% and 39% vs. 12%). Conclusion: In this retrospective analysis, NE support in donors prior to heart transplantation was unrelated to differing survival after heart transplantation. However, higher doses of donor NE were associated with prolonged ventilation, longer duration on IMC/ICU, and a higher need for extracorporeal life support in recipients post-HTx.

Incidence of Acute Kidney Injury Is Lower in High-Risk Patients Undergoing Percutaneous Coronary Intervention Supported with Impella Compared to ECMO.

Acute kidney injury (AKI) is a common complication post-PCI. Here, in a single-center observational registry, we compared the frequency of AKI in patients at elevated risk for AKI (based on Mehran risk stratification scoring) who underwent VA-ECMO- or Impella-supported high-risk PCI. A total of 28 patients scheduled for elective high-risk PCI with mechanical circulatory support were studied prospectively. All patients were turned down for surgery due to exceedingly high risk. Allocation to VA-ECMO (n=11) or Impella (n=17) was performed according to site-specific restrictions on the daily availability of the VA-ECMO platform as a prospective enrollment and performed prior to initiation of PCI. We analyzed AKI incidence as our primary endpoint, as well as PCI success, duration, and peripheral complications. All patients were successfully revascularized and had MCS weaned at the end of the procedure. Baseline GFR and procedural contrast media were similar. Despite similar risks for AKI as calculated by the Mehran score (35 ± 18.9 vs. 31 ± 16.6 %; p=0.55), patients supported by Impella during PCI demonstrated a reduced incidence of AKI (55 vs. 12 %; p=0.03). MCS-assisted high-risk PCI with VA-ECMO or Impella is feasible. However, Impella is associated with a shorter procedure time and a lower incidence of AKI.

Sublingual microcirculation predicts survival after out-of-hospital cardiac arrest.

BACKGROUND: Despite successful resuscitation with return of spontaneous circulation (ROSC), the prediction of survival in patients suffering out-of-hospital cardiac arrest (OHCA) remains difficult. Several studies have shown alterations in sublingual microcirculation in the critical ill. We hypothesized that early alterations in sublingual microcirculation may predict short-term survival after OHCA. METHODS: We prospectively included all adults admitted to our university hospital between April and September 2019 with ROSC following OHCA. Sidestream dark-field microscopy to obtain sublingual microcirculation was performed at admission and after 6, 12 and 24 hours. Primary outcome was survival until discharge. RESULTS: Twenty-five patients were included. Six hours after ROSC, the proportion of perfused small vessels (PPVsmall ) was lower in non-survivors than in survivors (85 ± 7.9 vs. 75 ± 6.6%; p = .01). PPVsmall did not correlate with serum lactate. Stratification for survival with cutoff values >78.4% for PPVsmall 6 h post-admission and <5.15 mmol/l for initial serum lactate as suggested by ROC-Analyses results in a positive predictive value of 100% and a negative one of 67% for our study population. CONCLUSION: Estimating short-term prognosis of OHCA patients with ROSC may be supported by measuring the PPVsmall at the sublingual microcirculation 6 hours after admission.

Local gastric RAAS inhibition improves gastric microvascular perfusion in dogs.

During circulatory shock, gastrointestinal microcirculation is impaired, especially via activation of the renin-angiotensin-aldosterone system. Therefore, inhibition of the renin-angiotensin-aldosterone system might be beneficial in maintaining splanchnic microcirculation. The aim of this study was to analyze whether locally applied losartan influences gastric mucosal perfusion (µflow, µvelo) and oxygenation (µHbO2) without systemic hemodynamic changes. In repetitive experiments six anesthetized dogs received 30 mg losartan topically on the oral and gastric mucosa during normovolemia and hemorrhage (-20% blood volume). Microcirculatory variables were measured with reflectance spectrometry, laser Doppler flowmetry and incident dark field imaging. Transpulmonary thermodilution and pulse contour analysis were used to measure systemic hemodynamic variables. Gastric barrier function was assessed via differential absorption of inert sugars. During normovolemia, losartan increased gastric µflow from 99 ± 6 aU to 147 ± 17 aU and µvelo from 17 ± 1 aU to 19 ± 1 aU. During hemorrhage, losartan did not improve µflow. µvelo decreased from 17 ± 1 aU to 14 ± 1 aU in the control group. Application of losartan did not significantly alter µvelo (16 ± 1 aU) compared to the control group and to baseline levels (17 ± 1 aU). No effects of topical losartan on macrohemodynamic variables or microcirculatory oxygenation were detected. Gastric microcirculatory perfusion is at least partly regulated by local angiotensin receptors. Topical application of losartan improves local perfusion via vasodilation without significant effects on systemic hemodynamics. During mild hemorrhage losartan had minor effects on regional perfusion, probably because of a pronounced upstream vasoconstriction.