Search

Background Human parvovirus B19 (B19V) infection and damage of circulating angiogenic cells (CAC) results in dysfunctional endogenous vascular repair (DEVR) with secondary end-organ damage. Trafficking of CAC is regulated by SDF-1α and the respective receptor CXCR4. We thus tested the hypothesis of a deregulated CXCR4/SDF-1α axis in symptomatic B19V-cardiomyopathy. Methods CAC were infected in vitro with B19V and transfected with B19V-components. Read-out were: CXCR4-expression and migratory capacity at increasing doses of SDF-1α. In 31 patients with chronic B19V-cardiomyopathy compared to 20 controls read-outs were from blood: migratory capacity, CXCR4 expression on CAC, serum SDF-1α; from cardiac biopsies: SDF-1α mRNA, HIF-1α mRNA, microvascular density, resident cardiac stem cells (CSC), transcardiac gradients of CAC. Results In vitro B19V-infected CAC showed up-regulation of surface CXCR4 with increased migratory capacity further enhanced by elevated SDF-1α concentrations. Overexpression of the B19V capsid protein VP2 was associated with this effect. Chronic B19V-cardiomyopathy patients showed increased numbers of ischaemia mobilised CAC but DEVR as well as diminished numbers of CAC after transcardiac passage. Cardiac microvascular density and CSC were significantly reduced in B19V-cardiomyopathy. Conclusions We thus conclude that B19V infection has a direct VP2-mediated negative impact on trafficking of CAC in the presence of impaired cardiac regeneration.

People with physical disabilities (PD) suffer from consequences due to lack of physical activity and consequently, are at increased risk of chronic diseases. We aimed to evaluate the ability of a motorised assistive device for dynamic standing with weight-bearing in addition to standard state-of-the-art therapy to improve clinical outcome in a meta-analysis of available studies. A total of 11 studies were identified from different European countries analysing the effect of the dynamic device Innowalk. Raw data of nine studies were pooled including a total of 31 patients observed between 2009 and 2017. Standardised questionnaires and physical outcomes were examined in this exploratory meta-analysis. We recorded patients’ characteristics, duration, intensity, and location of usage as well as general clinical outcomes and improvement of passive range of motion (PROM). The analysed population consisted in 90% cases of patients younger than 18 years of age. Patients were severely disabled individuals (aged 8 (6–10) years; 58% male; 67% non-ambulatory, 86% cerebral palsy). A total of 94% used the Innowalk in a home-based or day-care setting. For nearly all individuals (94%), improvements were recorded for: walking or weight-bearing transfer (n= 13), control/strength of the trunk or head (n= 6), joint mobility (n= 14), sleep (n= 4 out of 6/67%), or muscle strength (n= 17), vital functions (n= 16), bowel function (n= 10), attention/orientation (n= 2). PROM of the hip (flexion, abduction, and adduction) significantly (p< 0.001 for multiple comparisons) increased after 1 month (p< 0.05 flexion, adduction) and further after 5 months (p< 0.05 each) in contrast (p< 0.05 each) to a control group with state-of-the-art therapy. Similarly, PROM showed a trend towards improvement in dorsal extension of the ankle (p= 0.07). In summary, this is the first report of a novel device with additional benefit to standard therapy for severe PD. These intriguing results warrant the planned prospective randomised controlled trial to prove the concept and mechanism of action of this device.

Aims: Human parvovirus B19 (B19V) infection directly induces apoptosis and modulates CXCR4 expression of infected marrow-derived circulating angiogenic cells (CACs). This leads to dysfunctional endogenous vascular repair. Treatment for B19V-associated disease is restricted to symptomatic treatment. Telbivudine, a thymidine analogue, established in antiviral treatment for chronic hepatitis B, modulates pathways that might influence induction of apoptosis. Therefore, we tested the hypothesis of whether telbivudine influences B19V-induced apoptosis of CAC. Methods and Results: Pretreatment of two CAC-lines, early outgrowth endothelial progenitor cells (eo-EPC) and endothelial colony-forming cells (ECFC) with telbivudine before in vitro infection with B19V significantly reduced active caspase-3 protein expression (−39% and −40%, both p < 0.005). Expression of Baculoviral Inhibitor of apoptosis Repeat-Containing protein 3 (BIRC3) was significantly downregulated by in vitro B19V infection in ECFC measured by qRT-PCR. BIRC3 downregulation was abrogated with telbivudine pretreatment (p < 0.001). This was confirmed by single gene PCR (p = 0.017) and Western blot analysis. In contrast, the missing effect of B19V on angiogenic gene expression postulates a post-transcriptional modulation of CXCR4. Conclusions: We for the first time show a treatment approach to reduce B19V-induced apoptosis. Telbivudine reverses B19V-induced dysregulation of BIRC3, thus, intervening in the apoptosis pathway and protecting susceptible cells from cell death. This approach could lead to an effective B19V treatment to reduce B19V-related disease.

BackgroundPatients with cardiomyopathy show a significantly increased risk for thromboembolic events due to a hypercoagulable state and platelet dysfunction. The pathophysiologic mechanism underlying the increasing platelet activity in patients with cardiomyopathy remains unclear. We performed a clinical study to elucidate the link between myocardial tissue alterations and platelet activation in patients with cardiomyopathy.MethodsA total of 30 patients with suspected cardiomyopathy and 10 healthy control patients were included in our study. Hemodynamic parameters were measured by catheterization and echocardiography. Endomyocardial biopsies were taken to determine myocardial inflammation. Flow cytometry was performed to examine the platelet activation by quantification of p-selectin and thrombospondin expression on platelets.ResultsThe p-selectin (8.46±3.67AU) and thrombospondin (26.56±23.21AU) expression was significantly correlated with the amount of CD3+ T cells (p-selectin: r=0.573, p

Human parvovirus B19 (B19V) DNA is highly prevalent in endothelial cells lining up intramyocardial arterioles and postcapillary venules of patients with chronic myocarditis and cardiomyopathies. We addressed the question of a possible stimulation of B19V gene expression in endothelial cells by infection with adenoviruses. Adenovirus infection led to a strong augmentation of B19V structural and nonstructural proteins in individual endothelial cells infected with B19V or transfected with an infectious B19V genome. Transactivation was mostly mediated at the level of transcription and not due to adenovirus-mediated induction of second-strand synthesis from the single-stranded parvoviral genome. The main adenoviral functions required were E1A and E4orf6, which displayed synergistic effects. Furthermore, a limited B19V genome replication could be demonstrated in endothelial cells and adenovirus infection induced the appearance of putative dimeric replication intermediates. Thus the almost complete block in B19V gene expression seen in endothelial cells can be abrogated by infection with other viruses.

Aims Coxsackievirus B3 (CVB3)-induced myocarditis, initially considered a sole immune-mediated disease, also results from a direct CVB3-mediated injury of the cardiomyocytes. Mesenchymal stem cells (MSCs) have, besides immunomodulatory, also anti-apoptotic features. In view of clinical translation, we first analysed whether MSCs can be infected by CVB3. Next, we explored whether and how MSCs could reduce the direct CVB3-mediated cardiomyocyte injury and viral progeny release, in vitro, in the absence of immune cells. Finally, we investigated whether MSC application could improve murine acute CVB3-induced myocarditis. Methods and results Phase contrast pictures and MTS viability assay demonstrated that MSCs did not suffer from CVB3 infection 4-12-24-48 h after CVB3 infection. Coxsackievirus B3 RNA copy number decreased in this time frame, suggesting that no CVB3 replication took place. Co-culture of MSCs with CVB3-infected HL-1 cardiomyocytes resulted in a reduction of CVB3-induced HL-1 apoptosis, oxidative stress, intracellular viral particle production, and viral progeny release in a nitric oxide (NO)-dependent manner. Moreover, MSCs required priming via interferon-γ (IFN-γ) to exert their protective effects. In vivo, MSC application improved the contractility and relaxation parameters in CVB3-induced myocarditis, which was paralleled with a reduction in cardiac apoptosis, cardiomyocyte damage, left ventricular tumour necrosis factor-α mRNA expression, and cardiac mononuclear cell activation. Mesenchymal stem cells reduced the CVB3-induced CD4- and CD8- T cell activation in an NO-dependent way and required IFN-γ priming. Conclusion We conclude that MSCs improve murine acute CVB3-induced myocarditis via their anti-apoptotic and immunomodulatory properties, which occur in an NO-dependent manner and require priming via IFN-γ.

BACKGROUND In a phase 1 study, we investigated whether interferon beta reduced endothelial damage in patients with cardiac persistence of human parvovirus B19 (B19V) infection. METHODS AND RESULTS In vitro, B19V infected cultivated endothelial cells (ECs), which led to a reduction in their viability (P = .007). Interferon beta suppressed B19V replication by 63% (P = .008) in ECs and increased their viability (P = .021). Circulating mature apoptotic ECs (CMAECs [CD45(-)CD146(+) cells expressing von Willebrand factor and annexin V]) and circulating progenitor cells (CPCs [CD34(+)KDR(+) cells]) were quantified by flow cytometry in 9 symptomatic patients with cardiac B19V infection before and after 6 months of interferon beta therapy (16 MU) and were compared to levels in 9 healthy control subjects. Endothelial dysfunction was measured using flow-mediated dilatation of the forearm. Patients with B19V persistence had significantly higher (P = .04) levels of CMAECs than did control subjects, which normalized after treatment (mean +/- standard deviation, 0.06% +/-0.08% vs 0.01% +/- 0.006%; P = .008). Similar improvement was shown for flow-mediated dilatation (P = .04) in the treatment group only (P = .017 for the comparison with untreated patients with B19V persistence n = 5). There were significantly higher numbers of CPCs in patients with B19V persistence before therapy (mean +/- standard deviation, 0.04% +/- 0.05% vs 0.01% +/- 0.004%; P = .02; than in control subjects, which normalized after treatment (P = .03). CONCLUSION Thus, we present (for the first time, to our knowledge) a modulation of virally induced chronic endothelial damage-specifically, EC apoptosis and endothelial regeneration.

Regulatory T cells (Treg) migrate into allografts and induce tolerance of the graft. Immunosuppressive Tregare found among CD4+CD25++T cells and specifically express the forkhead/winged transcription factor FOXP3. We hypothesized that activated T cells and Tregmight modulate the ongoing inflammation of the cardiac allograft (CA) and that the chronic inflammatory environment might influence the balance between these distinct cell types. We therefore quantified levels of activated T cells and CD4+CD25++Tregin the cardiac and systemic circulation in heart transplant recipients. To determine the influence of the allograft passage on these cells, transcardiac gradients were evaluated in CA recipients ( n = 22) compared with controls ( n = 18). Systemic levels of circulating Tregwere significantly lower in CA recipients (8.9 ± 1.3 μl) compared with controls (15.8 ± 1.6 μl; P = 0.002). Similarly, the proportion of Tregrelated to the total leukocyte number was significantly lower in CA recipients ( P < 0.01). In contrast, systemic levels of circulating activated CD4+T cells and of circulating plasmacytoid dendritic cells were similar in both groups. In transplant patients, numbers of Tregsignificantly decreased during transcardiac passage (3.0 ± 0.3 to 2.4 ± 0.3% of CD4+T cells, P < 0.01), and FOXP3+T cells invaded into the allograft. In contrast, numbers of activated CD4+T cells increased during passage through the allograft, even in the presence of effective immunosuppression. In conclusion, numbers of circulating immunosuppressive Tregare reduced in transplant recipients. Recruitment of Treginto the cardiac allograft during transcoronary passage may induce graft tolerance during subclinical inflammation potentially influencing allograft vasculopathy.

Anticoagulation in cardioversion for atrial fibrillation is performed using unfractionated heparin and oral anticoagulants. TEE-guided cardioversion, after achievement of therapeutic anticoagulation (1-3 days), may be an alternative to the traditional procedure (3-week anticoagulation followed by cardioversion). The quality of anticoagulation in atrial fibrillation has not been investigated in a randomised trial with TEE-guided cardioversion. We analysed respective data from the ACE trial on the quality of conventional anticoagulation, where most participating centres chose the TEE-guided approach.In a randomised, prospective, multicentre trial, we analysed the efficacy of unfractionated heparin plus phenprocoumon in 248 patients on an intention-to-treat basis. There were 2373 evaluable anticoagulation measurements (out of 2925 measurements) and 4 categories of anticoagulation quality (under-, target, over- and severe over-anticoagulation). Of patients with evaluable measurements, 88% received short-term anticoagulation (4 weeks) in TEE-guided cardioversion.The median time to achieve therapeutic anticoagulation (aPTTor =60 and80 s or INRor =2 and3) was 3 days. Anticoagulation values were out of therapeutic range in 69.5% of measurements during 4- or 7-week follow-up, and never within therapeutic range in 10% of patients. Of the 15 primary endpoints observed (death, thromboembolism and major bleeding complications), only 3 were in patients with anticoagulation measurements within therapeutic range.In this study setting, with predominance of 4 weeks anticoagulation in TEE-guided cardioversion for atrial fibrillation, therapeutic anticoagulation was reached within 3 days using conventional anticoagulation. Despite careful dose adjustments, anticoagulation was out of therapeutic range in almost 70% of total measurements and 80% of primary endpoints.

Caroline Schmidt-Lucke, Heinz-Peter SchultheissCharité Medical University Berlin, Campus Benjamin Franklin, Dept. of Cardiology and Pulmology, GermanyAbstract: Non-ST elevation acute coronary syndrome (NSTE-ACS) refers to a cardiovascular disorder characterized by intracoronary thrombus formation on a disrupted atherosclerotic plaque with partial or transient occlusion. Generation of thrombin resulting from exposure of collagen leads to activation of platelets and conversion of fibrinogen to fibrin, thus forming a platelet-rich thrombus. The main therapeutic objective is to protect the patient from thrombotic complications, independent of the choice of antithrombotic agents. The management of NSTE myocardial infarction (MI) is constantly evolving. For primarily conservative strategy, enoxaparin has been proven superior to unfractioned heparin (UFH). With early invasive strategy providing better clinical outcome compared with conservative strategy, the effectiveness of enoxaparin in reducing death and MI rates is now being reconsidered in the era of poly-pharmacotherapy, early percutaneous coronary interventions and drug eluting stents. Bleeding complications can be minimized by avoiding cross-over from UFH to enoxaparin or vice versa, or by reducing the dosage of enoxaparin. We review the studies of enoxaparin and discuss its current role in the contemporary treatment of NSTE-ACS.Keywords: low-molecular weight heparin, NSTEMI, treatment

Aims Statin therapy is associated with improved endothelial vasodilator function. The clinical availability of ezetimibe, a potent novel cholesterol absorption inhibitor, enables to differentiate lipid-lowering effects from potential non-lipid-lowering (pleiotropic) mechanisms of statins. Methods and results Forearm blood flow (FBF) responses to acetylcholine (ACH) and sodium nitroprusside (SNP) were measured by venous occlusion plethysmography in four prospectively defined groups of patients with stable coronary artery disease (CAD) before and after 4 weeks of lipid-lowering therapy. Group A ( n =15): de novo monotherapy with 10 mg/day ezetimibe; Group B ( n =15): 10 mg/day ezetimibe as an add-on to chronic simvastatin therapy with 20 mg/day; Group C ( n =15): dose escalation from chronic 10 to 40 mg/day atorvastatin; and Group D ( n =15): de novo monotherapy with 40 mg/day atorvastatin. After 4 weeks of therapy, LDL cholesterol levels were significantly reduced in all four groups. Neither ezetimibe monotherapy (Group A) nor ezetimibe combined with 20 mg simvastatin (Group B) was associated with an increase in ACH-mediated FBF responses after 4 weeks. In contrast, dose escalation of atorvastatin from 10 to 40 mg/day (Group C) or de novo therapy with 40 mg atorvastatin/day (Group D) was associated with a significant increase in ACH-mediated FBF responses ( P

Combined hyperlipidemia is associated with endothelial dysfunction. Atorvastatin has lipid-lowering and pleiotropic properties, including a protective effect on endothelial function. This study investigated the short- and medium-term effects of therapy with atorvastatin and of its discontinuation on lipid lowering and endothelial function. In 33 patients with combined hyperlipidemia who had been randomized and treated for 6 weeks with 40 mg of atorvastatin twice daily (n = 23) or placebo (n = 10), fasting lipid levels and flow-mediated dilation (FMD) of the brachial artery were measured at baseline, after 12 hours, 1 week, and 6 weeks during therapy, and 36 hours after discontinuation of therapy. Thereafter, all patients received 20 mg/day of atorvastatin for another 6 weeks. In the atorvastatin group, low-density lipoprotein cholesterol was decreased by 30% and 46% after 1 and 6 weeks, respectively (p

Background— The maintenance of endothelial integrity plays a critical role in preventing atherosclerotic disease progression. Endothelial progenitor cells (EPCs) were experimentally shown to incorporate into sites of neovascularization and home to sites of endothelial denudation. Circulating EPCs may thus provide an endogenous repair mechanism to counteract ongoing risk factor–induced endothelial injury and to replace dysfunctional endothelium. Methods and Results— In 120 individuals (43 control subjects, 44 patients with stable coronary artery disease, and 33 patients with acute coronary syndromes), circulating EPCs were defined by the surface markers CD34 + KDR + and analyzed by flow cytometry. Cardiovascular events (cardiovascular death, unstable angina, myocardial infarction, PTCA, CABG, or ischemic stroke) served as outcome variables over a median follow-up period of 10 months. Patients suffering from cardiovascular events had significantly lower numbers of EPCs ( P P =0.0009). By multivariate analysis, reduced EPC levels were a significant, independent predictor of poor prognosis, even after adjustment for traditional cardiovascular risk factors and disease activity (hazard ratio, 3.9; P Conclusions— Reduced levels of circulating EPCs independently predict atherosclerotic disease progression, thus supporting an important role for endogenous vascular repair to modulate the clinical course of coronary artery disease.

To relate levels of vascular endothelial growth factor (VEGF) and its soluble receptor, sFlt-1, with endothelial function in healthy smokers.Plasma levels of VEGF and sFlt-1 were measured by ELISA in 22 healthy smokers and 22 matched healthy non-smoking controls, and compared to flow- (FMD) and acetylcholine-mediated (AMD) vasodilatation (endothelial-dependent) (EDV) and nitroglycerine-mediated (NMD) vasodilatation (endothelial-independent) of lower extremities were measured with plethysmography.Smokers and controls had similar plasma VEGF levels, but sFlt-1 levels were lower in smokers than in controls (p0.01). AMD was lower in smokers compared to controls (p0.05), but FMD and NMD levels were similar. Smokers and controls with high AMD (12 ml/100 ml tissue/min) had significantly lower plasma VEGF levels (p0.001). An inverse correlation was found in both groups, between VEGF and AMD (smokers: r=-0.6, p0.01; controls: r=-0.71, p0.005) and with FMD (smokers: r=-0.56, p0.05; controls: r=-0.58, p0.005). There were no significant correlations between sFlt-1 with VEGF levels or endothelial-dependent dilatation.In conclusion, healthy smokers demonstrate abnormal AMD, and an inverse correlation between plasma VEGF levels (but not sFlt-1) with indices of endothelial dysfunction (FMD and AMD) exists. VEGF, and not sFlt-1, may be related to the pathogenesis of endothelial dysfunction in healthy smoking individuals.

Background— Anticoagulation in cardioversion of atrial fibrillation is currently performed with unfractionated heparin (UFH) and oral anticoagulants, with or without guidance by transesophageal echocardiography (TEE). Low-molecular-weight heparins may reduce the risk of bleeding, may obviate the need for intravenous access, and do not require frequent anticoagulation monitoring. Methods and Results— In a randomized, prospective multicenter trial, we compared the safety and efficacy of enoxaparin administered subcutaneously with intravenous UFH followed by the oral anticoagulant phenprocoumon in 496 patients scheduled for cardioversion of atrial fibrillation of >48 hours’ and ≤1 year’s duration. Patients were stratified to cardioversion with (n=431) and without (n=65) guidance by TEE. The study aimed to demonstrate noninferiority of enoxaparin compared with UFH+phenprocoumon with regard to the incidence of embolic events, all-cause death, and major bleeding complications. Secondary end points included successful cardioversion, maintenance of sinus rhythm until study end, and minor bleeding complications. Of 496 randomized patients, 428 were analyzed per protocol. Enoxaparin was noninferior to UFH+phenprocoumon with regard to the incidence of the composite primary end point in a per-protocol analysis (7 of 216 patients versus 12 of 212 patients, respectively; P =0.016) and in an intention-to-treat analysis (7 of 248 patients versus 12 of 248 patients, respectively; P =0.013). There was no significant difference between the 2 groups in the number of patients reverted to sinus rhythm. Conclusions— Enoxaparin is noninferior to UFH+phenprocoumon for prevention of ischemic and embolic events, bleeding complications, and death in TEE-guided cardioversion of atrial fibrillation. Its easier application and more stable anticoagulation may make it the preferred drug for initiation of anticoagulation in this setting.

In evidence-based weight-loss programs weight regain is common after an initial weight reduction. Eating slowly significantly lowers meal energy intake and hunger ratings. Despite this knowledge, obese individuals do not implement this behaviour. We, thus tested the hypothesis of changing eating behaviour with an intra-oral medical device leading to constant weight reduction in overweight and obesity. Six obese patients (6 men, age 56 ± 14, BMI 29 ± 2 kg / m2) with increased CVRF profile were included in this prospective study. All patients had been treated for obesity during the last 10 years in a single centre and had at least 3 frustrate evidence-based diets. Patients received a novel non-invasive intra-oral medical device to slow eating time. Further advice included not to count calories, to avoid any other form of diet, to take their time with their meals, and to eat whatever they liked. This device was used only during meals for the first 4 to 8 weeks for a total of 88 [20–160] hours. Follow-up period was 23 [15–38] months. During this period, patients lost 11% [5–20%] (p5%, and 67% (4/6) achieved a >10% bodyweight loss. In the course of the study, altered eating patterns were observed. There were no complications with the medical device. Of note, all patients continued to lose weight after the initial intervention period (p

Human parvovirus B19 (B19V) is a common pathogen in microvascular disease and cardiomyopathy, owing to infection of endothelial cells. B19V replication, however, is almost restricted to erythroid progenitor cells (ErPCs). Endothelial regeneration attributable to bone marrow-derived circulating angiogenic cells (CACs) is a prerequisite for organ function. Because of many similarities of ErPCs and CACs, we hypothesized that B19V is a perpetrator of impaired endogenous endothelial regeneration. B19V DNA and messenger RNA from endomyocardial biopsy specimens, bone marrow specimens, and circulating progenitor cells were quantified by polymerase chain reaction analysis. The highest B19V DNA concentrations were found in CD34(+)KDR(+) cells from 17 patients with chronic B19V-associated cardiomyopathy. B19V replication intermediates could be detected in nearly half of the patients. Furthermore, chronic B19V infection was associated with impaired endothelial regenerative capacity. B19V infection of CACs in vitro resulted in expression of transcripts encoding B19V proteins. The capsid protein VP1 was identified as a novel inducer of apoptosis, as were nonstructural proteins. Inhibition studies identified so-called death receptor signaling with activation of caspase-8 and caspase-10 to be responsible for apoptosis induction. B19V causally impaired endothelial regeneration with spreading of B19V in CACs in an animal model in vivo. We thus conclude that B19V infection and damage to CACs result in dysfunctional endogenous vascular repair, supporting the emergence of primary bone marrow disease with secondary end-organ damage.

Background: In cutaneous laser Doppler flow (LDF)-recordings, various forms of flowmotion or vasoactivity can be observed. It is still a matter of dispute, whether flowmotion is a phenomenon of physiological or pathophysiological conditions. Therefore, we tested the hypothesis of increased vasoactivity being typical for patients with various degrees of acute and chronic anemia as well as with chronic obstructive pulmonary disease (COPD). Patients and methods: We examined 12 healthy controls, 14 patients with COPD with a PO2 below 60 mmHg, 16 patients with chronic and 7 patients with acute anemia with an Hb below 12 g/dl. We used a simple LDF-technique on the dorsum of the forefoot. The regularity of blood flow frequencies was determined by calculation of the coefficient of variation. Results: Periods without vasoactivity (i.e constant flow pattern) were 21% in normal controls, 7% in patients with COPD and 2% in patients with acute or chronic anemia. Mean frequencies in the four groups varied between 3.8 and 4.8 cpm, with significant changes only in the group with acute blood loss. However, vasoactivity was significantly more regular in the COPD- and anemia-groups as compared to normal controls, with coefficients of variation of 47.4% for controls, 31.8% for COPD- and 29.3% for chronic and 35.1% for acute anemia-patients. Conclusions: The present paper shows that cutaneous vasoactivity is more regular in the three examined clinical entities of systemic tissue hypo-oxygenation, i.e. chronic and acute anemia and severe COPD as compared to healthy control subjects. Therefore, we hypothesize that increased vasoactivity constitutes a regulatory defense mechanism in cases of reduced oxygenation, by improving microcirculatory blood flow distribution.

AimsCirculating endothelial progenitor cells (EPC), involved in endothelial regeneration, neovascularisation, and determination of prognosis in cardiovascular disease can be characterised with functional assays or using immunofluorescence and flow cytometry. Combinations of markers, including CD34+KDR+ or CD133+KDR+, are used. This approach, however may not consider all characteristics of EPC. The lack of a standardised protocol with regards to reagents and gating strategies may account for the widespread inter-laboratory variations in quantification of EPC. We, therefore developed a novel protocol adapted from the standardised so-called ISHAGE protocol for enumeration of haematopoietic stem cells to enable comparison of clinical and laboratory data.Methods and resultsIn 25 control subjects, 65 patients with coronary artery disease (CAD; 40 stable CAD, 25 acute coronary syndrome/acute myocardial infarction (ACS)), EPC were quantified using the following approach: Whole blood was incubated with CD45, KDR, and CD34. The ISHAGE sequential strategy was used, and finally, CD45(dim)CD34(+) cells were quantified for KDR. A minimum of 100 CD34(+) events were collected. For comparison, CD45(+)CD34(+) and CD45(-)CD34(+) were analysed simultaneously. The number of CD45(dim)CD34(+)KDR(+) cells only were significantly higher in healthy controls compared to patients with CAD or ACS (p = 0.005 each, pConclusionOur newly established protocol adopted from the standardised ISHAGE protocol achieved higher accuracy in EPC enumeration confirming previous findings with respect to the correlation of EPC with disease activity and the increase of EPC during statin therapy. The data of this study show the CD45(dim) fraction to harbour EPC.

BACKGROUND: Circulating progenitor cells (CPC) contribute to the homeostasis of the vessel wall, and a reduced CPC count predicts cardiovascular morbidity and mortality. We tested the hypothesis that CPC count improves cardiovascular risk stratification and that this is modulated by low-grade inflammation. METHODOLOGY/PRINCIPAL FINDINGS: We pooled data from 4 longitudinal studies, including a total of 1,057 patients having CPC determined and major adverse cardiovascular events (MACE) collected. We recorded cardiovascular risk factors and high-sensitive C-reactive protein (hsCRP) level. Risk estimates were derived from Cox proportional hazard analyses. CPC count and/or hsCRP level were added to a reference model including age, sex, cardiovascular risk factors, prevalent CVD, chronic renal failure (CRF) and medications. The sample was composed of high-risk individuals, as 76.3% had prevalent CVD and 31.6% had CRF. There were 331 (31.3%) incident MACE during an average 1.7+/-1.1 year follow-up time. CPC count was independently associated with incident MACE even after correction for hsCRP. According to C-statistics, models including CPC yielded a non-significant improvement in accuracy of MACE prediction. However, the integrated discrimination improvement index (IDI) showed better performance of models including CPC compared to the reference model and models including hsCRP in identifying MACE. CPC count also yielded significant net reclassification improvements (NRI) for CV death, non-fatal AMI and other CV events. The effect of CPC was independent of hsCRP, but there was a significant more-than-additive interaction between low CPC count and raised hsCRP level in predicting incident MACE. CONCLUSIONS/SIGNIFICANCE: In high risk individuals, a reduced CPC count helps identifying more patients at higher risk of MACE over the short term, especially in combination with a raised hsCRP level.

In patients with coronary artery disease (CAD), higher numbers of circulating endothelial progenitor cells (EPC) favourably influence clinical outcome. Controversially, increased apoptosis of endothelial cells (EC) may reflect vascular damage. Statins have been shown to improve vascular damage and enhance EPC function and numbers. The availability of ezetimibe, a potent novel cholesterol absorption inhibitor, allows to distinguish between lipid-lowering and pleiotropic properties of statins.43 patients with CAD were assigned to receive either: de novo atorvastatin (group A; n=17), ezetimibe as add-on to chronic statin therapy (group B; n=14), or dose escalation of atorvastatin (group C; n=12) over 4 weeks. Circulating apoptotic EC (CD45-CD146+vWF+Annexin-V+) and EPC (CD34+KDR+) were quantified using flow cytometry. LDL cholesterol levels were significantly reduced in all treatment arms. Both statin groups, group A and group C, showed significantly reduced circulating apoptotic EC by 50% each (p0.01). On the other hand, there was a significant doubling in the numbers of circulating EPC in group A and group C (p0.005, each). Consequently, the endothelial damage-index calculated from numbers of circulating apoptotic mature EC related to EPC numbers, was improved in group A by 79% (p0.01) and in group C by 70% (p0.05). In contrast, sole LDL reduction by ezetimibe exerted no effect on any of the different circulating endothelial cell types.Thus, the improvement in numbers of EPC and reduction of mature apoptotic EC after 4 weeks of statin therapy, document a novel pleiotropic effect of statin therapy in patients with CAD.

To estimate, from the perspective of Statutory Health Insurance (SHI, third-party payer) in Germany, the economic consequences of using the subcutaneous low-molecular-weight heparin (LMWH) enoxaparin instead of intravenous unfractionated heparin followed by oral phenprocoumon (UFH/PPC) for anticoagulation in patients undergoing transesophageal echocardiography (TEE)-guided early electrical cardioversion (ECV) of persisting nonvalvular atrial fibrillation (AF) without intracardiac clot.The incremental cost for the enoxaparin-based regimen versus the UFH/PPC-based regimen was chosen as the target variable. A decision-analytic model considering the in- and outpatient sectors was used to quantify the target variable. Resource use during in- and outpatient treatment was taken from the Anticoagulation in Cardioversion using Enoxaparin (ACE) trial and from expert interviews with cardiologists in Germany in order to reflect the day-to-day conditions of clinical practice. Costs were given by SHI expenses for inpatient treatment and for medical services, drugs, disposables, and laboratory tests during outpatient treatment. These costs were determined by multiplying utilized resource items by the price or tariff of each item based on German healthcare regulations for the reference period of 2003/2004. According to the ACE trial, the evaluation encompassed 28 (26-30) treatment days with two consecutive phases. Phase I with 5 (3-12) days comprised diagnostics, start of anticoagulation, and ECV. Phase II with the remaining days consisted of continued anticoagulation and patient monitoring. The dosage of enoxaparin was 1 mg/kg bodyweight twice daily in treatment phase I followed by 40 mg twice daily with a bodyweight65 kg or 60 mg twice daily with a BWor =65 kg in treatment phase II. The daily dosages of UFH by continuous infusion and overlapping PPC were adjusted to an International Normalized Ratio of 2.0-3.0 in treatment phase I followed by 2.25mg PPC once daily in treatment phase II. Patients with any comorbidity and complication level (CCL) and those with low comorbidity and complications expected to occur in rare cases only (low-risk patients) were analyzed separately. In each base-case analysis, exclusively point estimates of all respective model parameters were applied.There were savings of 339 euro and 579 euro per patient receiving the enoxaparin-based regimen versus the UFH/PPC-based regimen in the case of patients with any CCL and of low-risk patients, respectively (1 euro approximate, equals $US1.25; first quarter 2004 values). In comprehensive sensitivity analyzes, the robustness of the model and its results was shown. First, the impact of the model parameters on the target variable for each patient group was quantified in a deterministic model. Secondly, the dependency of the target variable on random variables was described for each patient group using Monte Carlo simulation. Irrespective of the patient group, the cost weight and the base rate of hospitals for inpatient ECV in phase I turned out to have the greatest impact on the savings obtained by the enoxaparin-based regimen. In the case of patients with any CCL, this impact was about 1.4-fold of that of the probability of enoxaparin patients undergoing outpatient ECV in phase I. In the case of low-risk patients, the impact of the cost weight and the base rate of hospitals for inpatient ECV in phase I was about 4.1-fold of that of the price of enoxaparin 60 mg prefilled syringes in the outpatient sector. In 79% and 93% of 10,000 simulated comparisons each versus the UFH/PPC-based regimen, there were savings obtained by the enoxaparin-based regimen in patients with any CCL and in low-risk patients, respectively.Results of this evaluation showed that an enoxaparin-based regimen for TEE-guided ECV of AF in patients without intracardiac clot offers SHI in Germany a considerable saving potential when used instead of an UFH/PPC-based regimen.

Asymmetric dimethylarginine (ADMA) plasma levels have been shown to be elevated in diseases related to endothelial dysfunction such as hypertension, hyperlipidemia, diabetes mellitus, and others. It has been shown that ADMA predicts cardiovascular mortality in patients who have coronary heart disease (CHD). However, the question whether ADMA is an independent risk factor for CHD still remains unresolved.The CARDIAC study is a multicenter case-control study, designed to detect differences in ADMA plasma levels between patients with CHD and controls from the general population. We included in our analysis 131 cases and 131 controls, matched for age, sex, and body mass index.We found that cases had higher ADMA plasma levels than controls (0.70 micromol/L [0.59-0.87 micromol/L] vs 0.60 micromol/L [0.54-0.69 micromol/L], P.001). To evaluate the predictive power of ADMA regarding CHD, we calculated 2 multivariate logistic regression models including laboratory parameters and traditional risk factors. The odds ratio for ADMA in the multivariate model including the laboratory characteristics was 2.59 (1.61-4.17; P.001); the odds ratio for the multivariate model including other risk factors was 6.04 (2.56-14.25; P.001) for the third tertile (0.72 micromol/L) versus the first (0.58 micromol/L).We conclude from the results of our study that ADMA is an independent risk factor for CHD.

The mode and duration of anticoagulation in the setting of cardioversion of atrial fibrillation—either with or without guidance by transesophageal echocardiography (TEE)—is still an unresolved issue. Oral anticoagulation with warfarin or phenprocoumon is frequently used but may be associated with an increased risk of bleeding complications or, conversely, episodes of undercoagulation. Moreover, it takes several days to reach full anticoagulation with oral compounds. This phase may be covered with intravenous heparin but this requires prolonged hospitalization. Low-molecular weight heparin is an attractive alternative as it not only provides a safe and predictable level of anticoagulation with few side effects but can also be administered safely on an outpatient basis. In addition, anticoagulation monitoring is usually unnecessary. The ACE study (Anticoagulation in Cardioversion using Enoxaparin) compared the safety and efficacy of subcutaneous enoxaparin with intravenous heparin/oral phenprocoumon before and after cardioversion (stratified to TEE guidance or no TEE guidance). This article summarizes the study rationale and design. The results will be published shortly.

Shear stress modulates vascular structure and function through cytoskeletal remodeling and activation of signaling cascades. Elevated vascular endothelial growth factor (VEGF) concentrations are seen in atherosclerotic disease and after active increase of perfusion. Levels of soluble vascular cell adhesion molecule (sVCAM-1) are increased in atherosclerotic disease without strict correlation to disease progression. In vitro, increased shear stress induces a biphasic response of sVCAM-1. No data are available on in vivo downregulation of VEGF or sVCAM-1 in humans. In 24 healthy individuals, vascular function of lower extremities was assessed by plethysmography measuring flow-mediated dilation and through intra-arterial infusion of acetylcholine and nitroglycerine. Ten healthy individuals were challenged with cycle exercise testing. Cytokines were measured from citrate plasma from cubital and femoral vein blood. Plasma concentrations of VEGF and sVCAM-1 correlated with endothelium-dependent dilation. Two hours after acetylcholine-induced shear stress, plasma concentrations of sVCAM-1 levels were reduced by 31% (p

The role of low frequency flowmotion in physiological or pathophysiological settings is unclear. We performed various series of experiments in young anesthetized New Zealand white (NZW) rabbits. Many animals exhibited flowmotion during control conditions. However, they very often seemed to be in unstable physiological conditions, and our preset inclusion criteria (as to arterial pressure and blood gases) were frequently not met.Therefore, in a first series, we correlated these systematically with the incidence of flowmotion. Eleven of 35 anesthetized rabbits, subjected to extensive surgery, showed flowmotion with a median frequency of 1.5 cpm and a relative "amplitude" of 32%. Arterial pressure was 10 mmHg lower, bicarbonate, base-excess, and PCO(2) values and relative blood flow were also significantly lower compared to animals not exhibiting flowmotion. In a second series, we tested whether flowmotion could be induced by an isolated metabolic acidosis in animals meeting the inclusion criteria and not showing flowmotion at control. Here, flowmotion was induced in 9/10 cases (p < 0.01) 30 min after the start of an HCl-infusion. In a third study, we related the onset of flowmotion to the pressure/flow autoregulation curve. At locally reduced blood pressure all 23 rabbits exhibited flowmotion (p < 0,00001) in the gastrocnemius and the tenuissimus muscles, with maximum flowmotion at a locally reduced blood pressure of 30 mmHg; the LDF-flux level showing 67% of control flow.These results support the concept that low frequency periodic hemodynamics are a characteristic of pathophysiological conditions like hypoperfusion or acidosis rather than indicating a normal physiological state.

Peripheral circulation usually refers to the vasculature of the upper and lower extremities. Apart from bones and joints, the two systems supplied by the peripheral circulation are skeletal muscle and skin. All considerations made below assume an unimpaired cardiac function and venous return.

There were several errors present in figure 1 of this manuscript. In figure 1A the same image is presented for non-infected MSC 48h as for CVB3-infected 48h. The image of CVB3-infected 48h is wrongly positioned in place of CVB3-infected 24h. In addition, appropriate headings were not displayed above the images of Figure 1A. The correct figure is presented below: The authors apologize for the error.