Background: MicroRNAs (miR) have been proposed as novel biomarkers in patients with cardiovascular disease. The release kinetics of miRs in patients with acute myocardial infarction (AMI) are difficult to establish. Methods: We analyzed the release kinetics of circulating muscle-enriched miRs (miR-1, miR-21, miR-208a, miR-133a) measured by TaqMan polymerase chain reaction in patients with hypertrophic obstructive cardiomyopathy undergoing transcoronary ablation of septal hypertrophy (TASH), a procedure mimicking AMI. Consecutive patients (n=21) undergoing TASH were included. Serum samples were collected prior to and at 15, 30, 45, 60, 75, 90, and 105 min, and 2, 4, 8, and 24 h after TASH. Results: Circulating concentrations of miR-1 significant increased already after 15 min (>4-fold; P<0.01) with a peak after 75 min (>60-fold; P<0.001). MiR-21 concentrations did not increase during all time points. Concentrations of miR-133a were significantly increased at 15 minutes (2.9-fold; P<0.001). MiR-133a reached a plateau between 75 min and 480min (>50-fold change) and decreases afterwards (30-fold change at 24 hours). MiR-208a concentrations rise the first 75 min (>2-fold; P=0.01) without further increase during all time points. Serum concentrations of miR-1 positively correlated with the hs-cTnT release during the first 120 min after induction of myocardial infarction (r2=0.95; P<0.001). Similar correlations could be observed for miR-133a (r2=0.97; P<0.001). The serum concentrations of miR-21 and miR-208a did not show any significant correlation with hs-cTnT. Conclusion: miR-1, miR-208a, and miR-133a continuously rose during the first 4 h after induction of AMI. In particular, miR-1 and miR-133a were significantly increased at early time points. These results demonstrate the release kinetics of miRNAs, which are helpful for developing their potential use as biomarkers in patients with acute coronary syndrome.

Background: Cardiopulmonary resuscitation (CPR) is associated with low success rates and high variability in outcomes. Extracorporeal life support (ECLS) systems provide sufficient perfusion of vital organs during treatment of the cardiac arrest (CA) cause. The routine use of ECLS is still under investigation. This study aimed to identify predictors of mortality in patients with in-hospital cardiac arrest (IHCA) undergoing ECLS treatment. Method: We retrospectively studied the characteristics and clinical outcomes of 48 patients with IHCA and veno-arterial ECLS treatment during on-going CPR treated between January 2009 and December 2012. Left ventricular ejection fraction (LVEF) and laboratory measurements were analysed. LVEF at baseline was taken from the medical report before CA and was further evaluated after ECLS implantation and then every 24 h during and after successful weaning from ECLS. Survival was determined from time of cardiac arrest to 30 days. Results: The 30-day survival rate was 31.3% (15 of 48 patients). Baseline characteristics, initial laboratory measurements, baseline LVEF as well as LVEF after ECLS treatment were not significantly different between survivors and non-survivors. There was no difference regarding median CPR duration (survivors 40.5 min [IQR 18.8-51.5] vs. non-survivors 31.0 min [IQR 20.0-49.0]; P=0.80) and duration of ECLS system implantation time (survivors 21.0 min [IQR 10.0-29.5] vs. non-survivors 15.0 min [IQR 9.5-22.5]; P=0.39). The interval between CA and start of ECLS system set up did not show a significant difference among the groups (survivor 21.5 min [IQR 10.0-32.3] vs. non-survivor 17.5 min [IQR 5.0-30.0]; P=0.56). ECLS treatment duration was not significantly different between the two groups (survivors: 69.0 hours [IQR 21.0–178.0] vs. non-survivors 39.0 hours [IQR 5.0–129.0]; P=0.24). Conclusion: In prolonged IHCA with failing conventional measures rapid initiation of an adequate organ perfusion by means of ECLS may help to improve the outcome.

Background: Renal sympathetic denervation (RSD) represents a treatment option for patients with resistant arterial hypertension (HT). However, in several pat. (8-13%) even RSD is without any effect. Predicting parameters have not yet been described in detail for these non-responders. The angiogenetic factor soluble fms-like tyrosine kinase-1 (sFLT-1) is associated with endothelial dysfunction (EDF) and HT. Furthermore, a relation between essential HT and increased serum levels of Intercellular Cell Adhesion Molecule-1 (ICAM-1) and Vascular Cell Adhesion Molecule-1 (VCAM-1), as specific markers for EDF, has been reported. Thus, in the present study we aimed to evaluate, whether sFLT-1, ICAM-1 and VCAM-1 are predictive markers for adequate blood pressure reduction after RSD. Methods: A total of 55 consecutive patients. undergoing RSD (age:63.5±10.2yrs) were included to this study. We compared the serum levels of sFLT-1, ICAM-1 and VCAM-1 of responders and non-responders at baseline and 6 months after RSD. A non-responder was defined as an unsuccessful blood pressure (BP) reduction of <10 mmHg in the ambulatory 24 hours blood pressure measurement (ABPM) after 6 months follow up. Results: Significant systolic BP reduction of 28.1 [±8.9] mmHg (RRsys-baseline: 166 [SD: 9.3] mmHg; p<0.01) was documented in 46 (83.6%) patients in the 24-h ABPM 6 months after RSD. 9 patients were classified as non-resp. with a mean systolic BP reduction of 7.1 [±1.49] mmHg (RRsys-baseline: 162 [SD: 6.4] mmHg). sFLT-1 baseline levels of resp. were significantly higher as compared to non-resp.(149.9pg/ml [IQR: 126.7-177.9] vs. 110.2pg/ml [IQR: 77.0-135.1]; p<0.001). Accordingly,ICAM-1 and VCAM-1 baseline levels of resp. were significantly higher as compared to non-resp. (ICAM-1: 370.6 ng/ml [IQR: 262.9 – 544.5] vs. 240.4ng/ml [IQR: 207.6-324.5]; p< 0.001; VCAM-1: 1011.0 ng/ml [IQR: 804.9-1326.0] vs. 815.1 ng/ml [IQR: 673.7-999.8]; p<0.001). In both, resp. and non-resp., no significant changes of sFLT-1, ICAM-1 and VCAM-1 levels were measured 6 months after RSD. The predictive value of s-FLT-1, ICAM-1 and VCAM-1 serum levels at baseline, as markers for adequate RSD related BP reduction, was examined by ROC-analysis (AUC: s-FLT-1: 0.82 [0.718; 0.921,p<0.001; AUC ICAM-1: 0.754 [0.654; 0.854], p<0.001; VCAM-1: 0.684 [0.564; 804],p=0.01). Conclusion: Even RSD is an effective therapy option for resistant HT, several pat. do not respond for not yet clarified reasons. This study identified for the first time sFLT-1, ICAM-1 and VCAM-1 as potential markers with a predictive value indicating a responder or non-responder after RSD.

Background: Monocyte heterogeneity is increasingly regarded to play substantial role in several inflammatory disorders, including ischemic heart disease. The lack of a standardized and easily applicable flow cytometry (FCM) method for sequential murine monocyte subset analysis is a major limitation for studying the monocytic compartment in different mouse models of inflammation. In this study we used a newly established multiparameter FCM platform to analyze the intra-individual kinetics of circulating monocyte in a mouse model of myocardial infarction (MI). Methods: By applying a novel single-tube 12-antibody/6-colour FCM panel we first analyzed blood samples from 180 healthy age-matched male C57BL/6 mice. Minimal-volume sequential blood sampling (18-20 μl) was further used to display a longitudinal kinetics of distinct granulocyte, monocyte and macrophage subsets in mice following MI induction (1, 2, 3, 5, 7, 14 and 21 days after MI, n=10) or sham surgery (n=7). Functional cardiac parameters from recent to chronic myocardial infarction were recorded by sequential cardiac magnetic resonance imaging. Results: Following cross-sectional analysis we could provide, for the very first time, a detailed description of absolute numbers, relative subset composition and biological variation of circulating Ly6ChighCD43low "classical" (135.6±7 cells/μl; coefficient of variation, CV 68.8%), Ly6ClowCD43high "non-classical" (86.1±3.3 cells/μl; CV 51.1%), and Ly6CintCD43int "intermediate" (16±0.7 cells/μl; CV 59.3%) monocyte subsets in C57BL/6 mice. Using intra-individual longitudinal measurements after MI induction, a time-course of classical and non-classical monocytosis was recorded. This approach enabled a significant reduction of monocyte subset dispersion across all investigated time points following MI. Notably, we could detect a significant, previously not reported overlap in the global pattern of myeloid cell kinetics between MI and sham-operated animals. Conclusions: We describe for the first time a detailed quantification of circulating monocyte subsets in steady state and infarction-associated inflammatory response in mice. Application of minimal-volume intravital flow cytometry may help to reduce the impact of biological variability, whereas confounding effects of surgical sham procedures on the peripheral leukocyte compartment should always be considered when investigating a mouse model of myocardial infarction.

BACKGROUND:The release kinetics of cardiac troponin T measured with conventional vs high-sensitivity cardiac troponin T (hs-cTnT) assays in patients with acute myocardial infarction (AMI) is difficult to establish.METHODS:We analyzed the release kinetics of cTnT measured by fourth generation and high-sensitivity assays, creatine kinase-MB (CK-MB), and myoglobin in patients with hypertrophic obstructive cardiomyopathy undergoing transcoronary ablation of septal hypertrophy (TASH), a model of AMI. Consecutive patients (n = 21) undergoing TASH were included. Serum and EDTA-plasma samples were collected before and at 15, 30, 45, 60, 75, 90, and 105 min, and 2, 4, 8, and 24 h after TASH.RESULTS:cTnT concentrations measured by the hs assay were significantly increased at 15 min [21.4 ng/L, interquartile range (IQR) 13.3-39.7 ng/L vs 11.3 ng/L, IQR 6.0-18.8 ng/L at baseline; P = 0.031]. In comparison, cTnT concentrations measured by the conventional fourth generation assay increased significantly at 60 min (30.0 ng/L, IQR 20.0-30.0 ng/L vs <10.0 ng/L, IQR <10.0-10.0 ng/L; P < 0.01), CK-MB at 90 min (8.4 μg/L, IQR 6.9-14.4 μg/L vs 0.9 μg/L, IQR 0.4-1.1 μg/L; P < 0.01), and myoglobin at 30 min (188.0 μg/L, IQR 154.0-233.0 μg/L vs 38.0 μg/L, IQR 28.0-56.0; P < 0.01).CONCLUSIONS:cTnT concentrations measured by the hs assay were significantly increased after TASH at all of the time points, with a doubling at 15 min after induction of AMI, confirming earlier evidence of myocardial injury compared to the fourth generation cTnT assay and CK-MB and myoglobin.

Recently, we demonstrated that a fully differentiated tissue developed on a ventricular septal occluder that had been implanted due to infarct‐related septum rupture. We suggested that this tissue originated from circulating stem cells. The aim of the present study was to evaluate this hypothesis and to investigate the physiological differentiation and transdifferentiation potential of circulating stem cells. We developed an animal model in which a freely floating membrane was inserted into each the left ventricle and the descending aorta. Membranes were removed after pre‐specified intervals of 3 days, and 2, 6 and 12 weeks; the newly developed tissue was evaluated using quantitative RT‐PCR, immunohistochemistry and in situ hybridization. The contribution of stem cells was directly evaluated in another group of animals that were by treated with granulocyte macrophage colony‐stimulating factor (GM‐CSF) early after implantation. We demonstrated the time‐dependent generation of a fully differentiated tissue composed of fibroblasts, myofibroblasts, smooth muscle cells, endothelial cells and new blood vessels. Cells differentiated into early cardiomyocytes on membranes implanted in the left ventricles but not on those implanted in the aortas. Stem cell mobilization with GM‐CSF led to more rapid tissue growth and differentiation. The GM‐CSF effect on cell proliferation outlasted the treat ment period by several weeks. Circulating stem cells contributed to the development of a fully differentiated tissue on membranes placed within the left ventricle or descending aorta under physiological conditions. Early cardiomyocyte generation was identified only on membranes positioned within the left ventricle.

An important goal in cardiology is to minimize myocardial necrosis and to support a discrete but resilient scar formation after myocardial infarction (MI). Macrophages are a type of cells that influence cardiac remodelling during MI. Therefore, the goal of the present study was to investigate their transcriptional profile and to identify the type of activation during scar tissue formation. Ligature of the left anterior descending coronary artery was performed in mice. Macrophages were isolated from infarcted tissue using magnetic cell sorting after 5 days. The total RNA of macrophages was subjected to microarray analysis and compared with RNA from MI and LV-control. mRNA abundance of relevant targets was validated by quantitative real-time PCR 2, 5 and 10 days after MI (qRT-PCR). Immunohistochemistry was performed to localize activation type-specific proteins. The genome scan revealed 68 targets predominantly expressed by macrophages after MI. Among these targets, an increased mRNA abundance of genes, involved in both the classically (tumour necrosis factor alpha, interleukin 6, interleukin 1beta) and the alternatively (arginase 1 and 2, mannose receptor C type 1, chitinase 3-like 3) activated phenotype of macrophages, was found 5 days after MI. This observation was confirmed by qRT-PCR. Using immunohistochemistry, we confirmed that tumour necrosis factor alpha, representing the classical activation, is strongly transcribed early after ligature (2 days). It was decreased after 5 and 10 days. Five days after MI, we found a fundamental change towards alternative activation of macrophages with up-regulation of arginase 1. Our results demonstrate that macrophages are differentially activated during different phases of scar tissue formation after MI. During the early inflammatory phase, macrophages are predominantly classically activated, whereas their phenotype changes during the important transition from inflammation to scar tissue formation into an alternatively activated type.