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Although vasculo-protective effects of flavan-3-ols are widely accepted today, their impact on endothelial cell functions and molecular mechanisms of action involved is not completely understood. The aim of this study was to characterize the potential endothelium-protective effects of circulating epicatechin metabolites and to define underlying mechanisms of action by an integrated systems biology approach. Reduced leukocyte rolling over vascular endothelium was observed following epicatechin supplementation in a mouse model of inflammation. Integrative pathway analysis of transcriptome, miRNome and epigenome profiles of endothelial cells exposed to epicatechin metabolites revealed that by acting at these different levels of regulation, metabolites affect cellular pathways involved in endothelial permeability and interaction with immune cells. In-vitro experiments on endothelial cells confirmed that epicatechin metabolites reduce monocyte adhesion and their transendothelial migration. Altogether, our in-vivo and in-vitro results support the outcome of a systems biology based network analysis which suggests that epicatechin metabolites mediate their vasculoprotective effects through dynamic regulation of endothelial cell monocyte adhesion and permeability. This study illustrates complex and multimodal mechanisms of action by which epicatechin modulate endothelial cell integrity.

Orthotopic aortic transplantation using the sleeve technique reduces injury to the aorta with failure rate of only 10-20%. The time to anastomose the aorta in mice using the sleeve method was short and easy averaging 20 min, permitting studies of iso/allo grafts. The following article describes the aortic transplantation procedure used in our laboratory. The mice were anesthetized with a mixture of 1.5% volume isoflurane and 100% oxygen through a face mask. At this point, the segment of the aorta between the renal arteries and its bifurcation was separated from the vena cava, freely prepared and clampedat the proximal and distal segments with a single silk suture. Prior to the removal of the aorta, a saline solution containing heparin was injected into the inferior vena cava. Then the aorta was cut between the clamps and a saline heparin solution was used to flush the lumen. The sleeve technique with monofilament sutures was used in order to transplant the abdominal aorta in the orthotopic position.

Background: Cocoa flavanol intake, especially that of (-)-epicatechin, has been linked to beneficial effects on human cardiovascular function. However, cocoa also contains the methylxanthines theobromine and caffeine, which may also affect vascular function., Objective: We sought to determine whether an interaction between cocoa flavanols and methylxanthines exists that influences cocoa flavanol-dependent vascular effects., Design: Test drinks that contained various amounts of cocoa flavanols (0-820 mg) and methylxanthines (0-220 mg), either together or individually, were consumed by healthy volunteers (n = 47) in 4 different clinical studies-3 with a randomized, double-masked crossover design and 1 with 4 parallel crossover studies. Vascular status was assessed by measuring flow-mediated vasodilation (FMD), brachial pulse wave velocity (bPWV), circulating angiogenic cells (CACs), and blood pressure before and 2 h after the ingestion of test drinks., Results: Although cocoa flavanol intake increased FMD 2 h after intake, the consumption of cocoa flavanols with methylxanthines resulted in a greater enhancement of FMD. Methylxanthine intake alone did not result in statistically significant changes in FMD. Cocoa flavanol ingestion alone decreased bPWV and diastolic blood pressure and increased CACs. Each of these changes was more pronounced when cocoa flavanols and methylxanthines were ingested together. It is important to note that the area under the curve of the plasma concentration of (-)-epicatechin metabolites over time was higher after the co-ingestion of cocoa flavanols and methylxanthines than after the intake of cocoa flavanols alone. Similar results were obtained when pure (-)-epicatechin and the methylxanthines theobromine and caffeine were consumed together., Conclusion: A substantial interaction between cocoa flavanols and methylxanthines exists at the level of absorption, in which the methylxanthines mediate an increased plasma concentration of (-)-epicatechin metabolites that coincides with enhanced vascular effects commonly ascribed to cocoa flavanol intake. This trial was registered at clinicaltrials.gov as NCT02149238., (© 2017 American Society for Nutrition.)

The Rho family of small GTPases has been analyzed in cardiac physiology and pathophysiology including myocardial infarction (MI) in the last years. Contradictory results show either a protective or a declined effect of RhoA and the RhoA effector Rho-associated protein kinase (ROCK) in myocardial ischemia and reperfusion injury that is associated with cardiomyocyte survival and caspase-3 activation. Cardiac-specific deletion of Rac1 reduced ischemia reperfusion injury in diabetic hearts, whereas cardiomyocyte specific overexpression of active Rac1 predisposes the heart to increased myocardial injury with enhanced contractile dysfunction. GTPase-activating proteins (GAPs) control the activation of Rho proteins through stimulation of GTP hydrolysis. However, the impact of GAPs in myocardial ischemia and reperfusion injury remains elusive. Here we analyzed the role of oligophrenin1 (OPHN1), a RhoGAP with Bin/Amphiphysin/Rvs (BAR) domain known to regulate the activity of RhoA, Rac1 and Cdc42 in MI. The expression of Ophn1, RhoA and Rac1 is strongly upregulated 24h after myocardial ischemia. Loss of OPHN1 induced enhanced activity of Rho effector molecules leading to elevated cardiomyocyte apoptosis and increased migration of inflammatory cells into the infarct border zone of OPHN1 deficient mice. Consequently, echocardiography 24h after myocardial ischemia revealed declined left ventricle function in OPHN1 deficient mice. Our results indicate that OPHN1 mediated regulation of RhoA, Rac1 and Cdc42 is crucial for the preservation of cardiac function after myocardial injury., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Aim: To determine the impact of red blood cell distribution width on outcome in anemic patients undergoing transcatheter aortic valve implantation (TAVI)., Methods: In a retrospective single center cohort study we determined the impact of baseline red cell distribution width (RDW) and anemia on outcome in 376 patients with aortic stenosis undergoing TAVI. All patients were discussed in the institutional heart team and declined for surgical aortic valve replacement due to high operative risk. Collected data included patient characteristics, imaging findings, periprocedural in hospital data, laboratory results and follow up data. Blood samples for hematology and biochemistry analysis were taken from every patient before and at fixed intervals up to 72 h after TAVI including blood count and creatinine. Descriptive statistics were used for patient's characteristics. Kaplan-Meier survival curves were used for time to event outcomes. A recursive partitioning regression and classification was used to investigate the association between potential risk factors and outcome variables., Results: Mean age in our study population was 81 ± 6.1 years. Anemia was prevalent in 63.6% (n = 239) of our patients. Age and creatinine were identified as risk factors for anemia. In our study population, anemia per se did influence 30-d mortality but did not predict longterm mortality. In contrast, a RDW > 14% showed to be highly predictable for a reduced short- and longterm survival in patients with aortic valve disease after TAVI procedure., Conclusion: Age and kidney function determine the degree of anemia. The anisocytosis of red blood cells in anemic patients supplements prognostic information in addition to that derived from the WHO-based definition of anemia.

S-nitrosation of macrophage migration inhibitory factor (MIF) has been shown to be cytoprotective in myocardial ischaemia/reperfusion (I/R) injury. Since the exact mechanism of action is unknown, we here characterise the cardioprotective effects of targeted intracellular accumulation of MIF in myocardial I/R injury. We used different in vivo, ex vivo and in vitro models of myocardial I/R and hypoxia/reoxygenation (H/R) injury to determine MIF levels by immunoblots and ELISA in different phases of reperfusion and reoxygenation, respectively. We discovered a rapid decrease of cardiac MIF that was specific to the early phase of reperfusion. Posttranslational modification of MIF via S-nitrosation--proofed by a modified version of the Biotin Switch Assay--prevented this rapid decrease, leading to a targeted intracellular accumulation of MIF in the early phase of reperfusion. Intracellular MIF accumulation preserved the intracellular ability of MIF to reduce oxidative stress as shown by hydrogen peroxide and aconitase activity measurements. Infarct size measurements by TTC staining showed an overall enhanced cardioprotective effect of this protein by reduction of reperfusion injury. In summary, we have unravelled a novel mechanism of MIF-mediated cardioprotection. Targeted intracellular accumulation of MIF by S-nitrosation may offer a novel therapeutic approach in the treatment of myocardial I/R-injury.

Cocoa flavanol (CF) intake improves endothelial function in patients with cardiovascular risk factors and disease. We investigated the effects of CF on surrogate markers of cardiovascular health in low risk, healthy, middle-aged individuals without history, signs or symptoms of CVD. In a 1-month, open-label, one-armed pilot study, bi-daily ingestion of 450 mg of CF led to a time-dependent increase in endothelial function (measured as flow-mediated vasodilation (FMD)) that plateaued after 2 weeks. Subsequently, in a randomised, controlled, double-masked, parallel-group dietary intervention trial (Clinicaltrials.gov: NCT01799005), 100 healthy, middle-aged (35-60 years) men and women consumed either the CF-containing drink (450 mg) or a nutrient-matched CF-free control bi-daily for 1 month. The primary end point was FMD. Secondary end points included plasma lipids and blood pressure, thus enabling the calculation of Framingham Risk Scores and pulse wave velocity. At 1 month, CF increased FMD over control by 1·2 % (95 % CI 1·0, 1·4 %). CF decreased systolic and diastolic blood pressure by 4·4 mmHg (95 % CI 7·9, 0·9 mmHg) and 3·9 mmHg (95 % CI 6·7, 0·9 mmHg), pulse wave velocity by 0·4 m/s (95 % CI 0·8, 0·04 m/s), total cholesterol by 0·20 mmol/l (95 % CI 0·39, 0·01 mmol/l) and LDL-cholesterol by 0·17 mmol/l (95 % CI 0·32, 0·02 mmol/l), whereas HDL-cholesterol increased by 0·10 mmol/l (95 % CI 0·04, 0·17 mmol/l). By applying the Framingham Risk Score, CF predicted a significant lowering of 10-year risk for CHD, myocardial infarction, CVD, death from CHD and CVD. In healthy individuals, regular CF intake improved accredited cardiovascular surrogates of cardiovascular risk, demonstrating that dietary flavanols have the potential to maintain cardiovascular health even in low-risk subjects.

Purpose: Development of AV-block is a frequent complication associated with transcatheter aortic valve implantation (TAVI). To date little is known about the predictive value of the HV-interval prior to TAVI with respect to the risk of AV-block development., Methods and Results: HV-interval was determined in 25 consecutive elderly patients with severe aortic valve stenosis (AS) before and immediately after TAVI. All patients subsequently underwent TAVI and 8 of these 25 patients (32%) developed complete AV-block during the TAVI procedure requiring permanent pacemaker implantation. Six of these 8 patients (75%) had marked HV prolongation (>54 ms). Pre-procedural HV-interval was significantly prolonged in the subgroup developing complete AV-block (62.1 ms±13.0 vs 49.2 ms±12.9; P=0.029). Prolongation of the HV-interval above 54 ms was associated with a higher rate of complete AV-block (sensitivity 75.0%, specificity 77.8%, P=0.01)., Conclusions: HV-interval was prolonged in approximately one third of our elderly patients with aortic valve stenosis and associated with a high rate of complete AV-block following TAVI. HV-interval is easily obtained during TAVI screening procedures, thus facilitating identification of patients at risk for complete AV-block due to TAVI and consequently enabling bespoke risk management.

We have recently shown that dipyrone (metamizole), a non-opioid analgesic, can nullify aspirin (acetylsalicylic acid; ASA) antiplatelet effects in patients with coronary artery disease (CAD). In this study, we analysed the aspirin and dipyrone drug-drug interaction in order to identify strategies to prevent the dipyrone induced inhibition of asprin antiplatelet effects. Platelet function was measured by arachidonic acid-induced light-transmission aggregometry, thromboxane (TX) B2- formation by immunoassay. Dipyrone metabolite plasma levels were determined by high-performance-liquid-chromatography (HPLC). In seven healthy individuals, in vitro ASA (30 µM/ 100 µM/ 300 µM/ 1,000 µM) and dipyrone (10 µM) coincubation revealed, that the aspirin and dipyrone interaction can be overcome by increasing doses of aspirin. In 36 aspirin and dipyrone comedicated CAD patients, addition of ASA (30 µM/ 100 µM) in vitro inhibited, but did not completely overcome the dipyrone induced reduction of aspirin antiplatelet effects. Notably, the inhibition of thromboxane formation in aspirin and dipyrone comedicated CAD patients coincided with dipyrone plasma levels. In a cross-over designed study in four healthy individuals, we were able to prove that inhibition of aspirin (100 mg/ day) effects by dipyrone (750 mg/ day) was reversible. Furthermore, aspirin (100 mg/ day) medication prior to dipyrone (750 mg/ day) intake prevented the inhibition of antiplatelet effects by dipyrone in 12 healthy individuals. In conclusion, aspirin medication prior to dipyrone intake preserves antiplatelet effects, circumventing the pharmacodynamic drug-drug interaction at the level of cyclooxygenase-1.

Dietary intervention studies suggest that flavan-3-ol intake can improve vascular function and reduce the risk of cardiovascular diseases (CVD). However, results from prospective studies failed to show a consistent beneficial effect. Associations between flavan-3-ol intake and CVD risk in the Norfolk arm of the European Prospective Investigation into Cancer and Nutrition (EPIC-Norfolk) were investigated. Data were available from 24,885 (11,252 men; 13,633 women) participants, recruited between 1993 and 1997 into the EPIC-Norfolk study. Flavan-3-ol intake was assessed using 7-day food diaries and the FLAVIOLA Flavanol Food Composition database. Missing data for plasma cholesterol and vitamin C were imputed using multiple imputation. Associations between flavan-3-ol intake and blood pressure at baseline were determined using linear regression models. Associations with CVD risk were estimated using Cox regression analyses. Median intake of total flavan-3-ols was 1034mg/d (range: 0-8531mg/d) for men and 970mg/d (0-6695mg/d) for women, median intake of flavan-3-ol monomers was 233mg/d (0-3248mg/d) for men and 217 (0-2712mg/d) for women. There were no consistent associations between flavan-3-ol monomer intake and baseline systolic and diastolic blood pressure (BP). After 286,147 person-years of follow-up, there were 8463 cardiovascular events and 1987 CVD related deaths; no consistent association between flavan-3-ol intake and CVD risk (HR 0.93, 95% CI: 0.87; 1.00; Q1 vs Q5) or mortality was observed (HR 0.93, 95% CI: 0.84; 1.04). Flavan-3-ol intake in EPIC-Norfolk is not sufficient to achieve a statistically significant reduction in CVD risk., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Aim: Inflammation is a hallmark of cardiac healing after myocardial infarction and it determines subsequent cardiovascular morbidity and mortality. The aim of the present study was to explore whether inflammation imaging with two perfluorocarbon (PFC) nanoemulsions and fluorine magnetic resonance imaging ((19)F MRI) is feasible at 3.0 T with sufficient signal-to-noise ratio (SNR) using explanted hearts, an (19)F surface coil and dedicated MR sequences., Methods and Results: Acute myocardial infarction (AMI) was induced by balloon angioplasty (50 min) of the distal left anterior descending artery in 12 pigs. One day thereafter, PFCs were injected intravenously to label circulating monocytes. Either emulsified perfluoro-15-crown-5 ether or already clinically applied perfluorooctyl bromide (PFOB) was applied. Four days after AMI and immediately after gadolinium administration, hearts were explanted and imaged with a 3.0 T Achieva MRI scanner. (19)F MRI could be acquired with an SNR of >15 using an in-plane resolution of 2 × 2 mm(2) within <20 min for both agents. Combined late gadolinium enhancement (LGE) and (19)F MRI revealed that (19)F signal was inhomogenously distributed across LGE myocardium reflecting patchy macrophage infiltration as confirmed by histology. In whole hearts, we found an apico-basal (19)F gradient within LGE-positive myocardium. The (19)F-positive volume was always smaller than LGE volume. Ex vivo experiments on isolated monocytes revealed that pig and human cells phagocytize PFCs even more avidly than mouse monocytes., Conclusion: This pilot study demonstrates that (19)F MRI at 3.0 T with clinically applicable PFOB is feasible, thus highlighting the potential of (19)F MRI to monitor the inflammatory response after AMI., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.)

Increased vascular stiffness, endothelial dysfunction, and isolated systolic hypertension are hallmarks of vascular aging. Regular cocoa flavanol (CF) intake can improve vascular function in healthy young and elderly at-risk individuals. However, the mechanisms underlying CF bioactivity remain largely unknown. We investigated the effects of CF intake on cardiovascular function in healthy young and elderly individuals without history, signs, or symptoms of cardiovascular disease by applying particular focus on functional endpoints relevant to cardiovascular aging. In a randomized, controlled, double-masked, parallel-group dietary intervention trial, 22 young (<35 years) and 20 elderly (50-80 year) healthy, male non-smokers consumed either a CF-containing drink (450 mg CF) or nutrient-matched, CF-free control drink bi-daily for 14 days. The primary endpoint was endothelial function as measured by flow-mediated vasodilation (FMD). Secondary endpoints included cardiac output, vascular stiffness, conductance of conduit and resistance arteries, and perfusion in the microcirculation. Following 2 weeks of CF intake, FMD improved in young (6.1 ± 0.7 vs. 7.6 ± 0.7 %, p < 0.001) and elderly (4.9 ± 0.6 vs. 6.3 ± 0.9 %, p < 0.001). Secondary outcomes demonstrated in both groups that CF intake decreased pulse wave velocity and lowered total peripheral resistance, and increased arteriolar and microvascular vasodilator capacity, red cell deformability, and diastolic blood pressure, while cardiac output remained affected. In the elderly, baseline systolic blood pressure was elevated, driven by an arterial-stiffness-related augmentation. CF intake decreased aortic augmentation index (-9 %) and thus systolic blood pressure (-7 mmHg; Clinicaltrials.gov: NCT01639781). CF intake reverses age-related burden of cardiovascular risk in healthy elderly, highlighting the potential of dietary flavanols to maintain cardiovascular health.

Purpose: Nitric oxide (NO) is constitutively produced and released from the endothelium and several blood cell types by the isoform 3 of the NO synthase (NOS3). We have shown that NO protects against myocardial ischemia/reperfusion (I/R) injury and that depletion of circulating NOS3 increases within 24 h of ischemia/reperfusion the size of myocardial infarction (MI) in chimeric mice devoid of circulating NOS3. In the current study we hypothesized that circulating NOS3 also affects remodeling of the left ventricle following reperfused MI., Methods: To analyze the role of circulating NOS3 we transplanted bone marrow of NOS3-/- and wild type (WT) mice into WT mice, producing chimerae expressing NOS3 only in vascular endothelium (BC-/EC+) or in both, blood cells and vascular endothelium (BC+/EC+). Both groups underwent 60 min of coronary occlusion in a closed-chest model of reperfused MI. During the 3 weeks post MI, structural and functional LV remodeling was serially assessed (24 h, 4 d, 1 w, 2 w and 3 w) by echocardiography. At 72 hours post MI, gene expression of several extracellular matrix (ECM) modifying molecules was determined by quantitative RT-PCR analysis. At 3 weeks post MI, hemodynamics were obtained by pressure catheter, scar size and collagen content were quantified post mortem by Gomori's One-step trichrome staining., Results: Three weeks post MI, LV end-systolic (53.2±5.9 μl; ***p≤0.001; n = 5) and end-diastolic volumes (82.7±5.6 μl; *p<0.05; n = 5) were significantly increased in BC-/EC+, along with decreased LV developed pressure (67.5±1.8 mm Hg; n = 18; ***p≤0.001) and increased scar size/left ventricle (19.5±1.5%; n = 13; **p≤0.01) compared to BC+/EC+ (ESV: 35.6±2.2 μl; EDV: 69.1±2.6 μl n = 8; LVDP: 83.2±3.2 mm Hg; n = 24; scar size/LV13.8±0.7%; n = 16). Myocardial scar of BC-/EC+ was characterized by increased total collagen content (20.2±0.8%; n = 13; ***p≤0.001) compared to BC+/EC+ (15.9±0.5; n = 16), and increased collagen type I and III subtypes., Conclusion: Circulating NOS3 ameliorates maladaptive left ventricular remodeling following reperfused myocardial infarction.

Aims: Degenerative aortic valve stenosis (AVS) is independently associated with endothelial dysfunction and increased levels of circulating endothelium-derived microparticles (EMPs) as a marker of compromised endothelial integrity. The aim of this study was to investigate whether therapy for severe AVS by transcatheter aortic valve implantation (TAVI) improves endothelial function and decreases EMPs., Methods and Results: Fifty-six patients with indication for TAVI due to symptomatic severe AVS were prospectively enrolled. Brachial wall shear stress (WSS), endothelial function and circulating microparticles (MPs) were measured before and three months following TAVI. Endothelial function was assessed as flow-mediated dilation (FMD) using ultrasound. MP subpopulations were discriminated by flow cytometry according to the expression of established surface antigens: CD31+/CD41-, CD144+ and CD62E+ as EMPs and CD41+ as platelet-derived MPs (PMPs). In patients with severe AVS, decreased brachial WSS was an independent predictor of low FMD. At three-month follow-up after TAVI, WSS and FMD increased along with decreased levels of EMPs as compared to pre TAVI. Decrease of CD31+/CD41-, CD144+ and CD62E+ EMP levels correlated with the increase of FMD., Conclusions: Therapy for AVS by TAVI was associated with improved endothelial function and integrity indicating beneficial effects of TAVI on systemic arterial function.

Dual antiplatelet therapy (DAPT) is recommended early after transcatheter aortic valve implantation (TAVI) procedure at the moment despite the lack of evidence. Two small randomized trials failed to demonstrate DAPT to be superior to aspirin alone in TAVI patients. However, it is known that there are substantial response variabilities to antiplatelet medication. We aimed to investigate high on-treatment platelet reactivity (HTPR), low on-treatment platelet reactivity (LTPR) to clopidogrel as well as HTPR to aspirin in patients undergoing TAVI procedure. We analyzed data of 140 TAVI patients in a real world observational study. Platelet function assays (clopidogrel-vasodilator-stimulated protein phosphorylation assay; aspirin-light-transmission aggregometry) have been performed during hospital course. Clinical complications were investigated during 30 days follow-up and defined using the valve academic research consortium standardized criteria. HTPR to clopidogrel occurred in 87 (62%) patients and LTPR in 9 (6.4%) patients. Aspirin antiplatelet effects were insufficient in 25 (18%) patients. Clinical complications were observed in 35 (25%) patients. Ischemic events occurred in 6 (4%), bleeding complications in 28 (20%) patients. There were no differences regarding the incidence of HTPR/LTPR in patients with overall complications, ischemic events or bleeding events. HTPR to clopidogrel is very frequent in TAVI patients. However bleeding complications are frequent and ischemic events are rare. Therefore, future clinical trials investigating the optimal antithrombotic regiment in TAVI patients should consider this high incidence of HTPR to clopidogrel and monitor clopidogrel antiplatelet effects carefully., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Introduction: The aim of our study was to develop a reproducible murine model of elastase-induced aneurysm formation combined with aortic transplantation., Methods: Adult male mice (n = 6-9 per group) underwent infrarenal, orthotopic transplantation of the aorta treated with elastase or left untreated. Subsequently, both groups of mice were monitored by ultrasound until 7 weeks after grafting., Results: Mice receiving an elastase-pretreated aorta developed aneurysms and exhibited a significantly increased diastolic vessel diameter compared to control grafted mice at 7 week after surgery (1.11 ± 0.10 mm vs. 0.75 ± 0.03 mm; p ≤ 0,001). Histopathological examination revealed disruption of medial elastin, an increase in collagen content and smooth muscle cells, and neointima formation in aneurysm grafts., Conclusions: We developed a reproducible murine model of elastase-induced aneurysm combined with aortic transplantation. This model may be suitable to investigate aneurysm-specific inflammatory processes and for use in gene-targeted animals.

Aims: Introduction of a novel contrast injection protocol during rotational C-arm CT (RCT) in cardiac catheterisation of patients with aortic stenosis for aortic root assessment., Methods and Results: Fifty-two patients underwent RCT imaging with contrast injection performed either into the aorta (Ao-RCT, n=25) or into the left ventricle (LV-RCT, n=27). Aortic annulus diameters were assessed in a multiplanar reconstruction view and compared with corresponding multidetector computed tomography (MDCT). LV contrast injection additionally enabled measurement of the left ventricular outflow tract (LVOT). LV-RCT improved the accuracy of annulus measurements and correlated well with MDCT data in comparison with Ao-RCT and MDCT (r=0.91, r=0.76, respectively). The Bland-Altman analysis showed smaller differences in MDCT and LV-RCT annulus measurements than between MDCT and Ao-RCT (LV-RCT: mean=0.4 mm, limits of agreement -1.5-2.3 mm vs. Ao-RCT: mean=0.1 mm, limits of agreement -3.4-3.6 mm). The inter-observer agreement for the annulus measurements was significantly increased for LV-RCT as calculated by the intra-class coefficient (ICC=0.85) in comparison with Ao-RCT (ICC=0.52)., Conclusions: Cardiac catheterisation including LV-RCT offers complementary assessment of left ventricular function, aortic valve anatomy, coronary angiography and arterial access routes. LV-RCT for aortic root measurements shows better correlation to MDCT than standard Ao-RCT protocols.

Dietary interventions with flavan-3-ols have shown beneficial effects on vascular function. The translation of these findings into the context of the health of the general public requires detailed information on habitual dietary intake. However, only limited data are currently available for European populations. Therefore, in the present study, we assessed the habitual intake of flavan-3-ol monomers, proanthocyanidins (PA) and theaflavins in the European Union (EU) and determined their main food sources using the EFSA (European Food Safety Authority) Comprehensive European Food Consumption Database. Data for adults aged 18-64 years were available from fourteen European countries, and intake was determined using the FLAVIOLA Flavanol Food Composition Database, developed for the present study and based on the latest US Department of Agriculture and Phenol-Explorer databases. The mean habitual intake of flavan-3-ol monomers, theaflavins and PA ranged from 181 mg/d (Czech Republic) to 793 mg/d (Ireland). The highest intakes of flavan-3-ol monomers and theaflavins were observed in Ireland (191/505 mg/d) and the lowest intakes in Spain (24/9 mg/d). In contrast, the daily intake of PA was highest in Spain (175 mg/d) and lowest in The Netherlands (96 mg/d). Main sources were tea (62%), pome fruits (11%), berries (3%) and cocoa products (3%). Tea was the major single contributor to monomer intake (75%), followed by pome fruits (6%). Pome fruits were also the main source of PA (28%). The present study provides important data on the population-based intake of flavanols in the EU and demonstrates that dietary intake amounts for flavan-3-ol monomers, PA and theaflavins vary significantly across European countries. The average habitual intake of flavan-3-ols is considerably below the amounts used in most dietary intervention studies.

Nitric oxide (NO) derived from endothelial NO synthase (NOS3) plays a central role in myocardial ischemia/reperfusion (I/R)-injury. Subsets of circulating blood cells, including red blood cells (RBCs), carry a NOS3 and contribute to blood pressure regulation and RBC nitrite/nitrate formation. We hypothesized that the circulating blood born NOS3 also modulates the severity of myocardial infarction in disease models. We cross-transplanted bone marrow in wild-type and NOS3(-/-) mice with wild-type mice, producing chimeras expressing NOS3 only in vascular endothelium (BC-/EC+) or in both blood cells and vascular endothelium (BC+/EC+). After 60-min closed-chest coronary occlusion followed by 24 h reperfusion, cardiac function, infarct size (IS), NOx levels, RBCs NO formation, RBC deformability, and vascular reactivity were assessed. At baseline, BC-/EC+ chimera had lower nitrite levels in blood plasma (BC-/EC+: 2.13 ± 0.27 μM vs. BC+/EC+ 3.17 ± 0.29 μM; *p < 0.05), reduced DAF FM associated fluorescence within RBCs (BC-/EC+: 538.4 ± 12.8 mean fluorescence intensity (MFI) vs. BC+/EC+: 619.6 ± 6.9 MFI; ***p < 0.001) and impaired erythrocyte deformability (BC-/EC+: 0.33 ± 0.01 elongation index (EI) vs. BC+/EC+: 0.36 ± 0.06 EI; *p < 0.05), while vascular reactivity remained unaffected. Area at risk did not differ, but infarct size was higher in BC-/EC+ (BC-/EC+: 26 ± 3 %; BC+/EC+: 14 ± 2 %; **p < 0.01), resulting in decreased ejection fraction (BC-/EC+ 46 ± 2 % vs. BC+/EC+: 52 ± 2 %; *p < 0.05) and increased end-systolic volume. Application of the NOS inhibitor S-ethylisothiourea hydrobromide was associated with larger infarct size in BC+/EC+, whereas infarct size in BC-/EC+ mice remained unaffected. Reduced infarct size, preserved cardiac function, NO levels in RBC and RBC deformability suggest a modulating role of circulating NOS3 in an acute model of myocardial I/R in chimeric mice.

Pulmonary vascular injury is a rare but life-threatening complication of Swan-Ganz catheterization. We report an 82-year old patient who underwent right heart catheterization by a balloon-tipped catheter because of suspected pulmonary hypertension. After deflation of the catheter in the wedge position, hemoptoe appeared associated with acute respiratory insufficiency requiring respiratory support by intubation and mechanical ventilation. Pulmonary angiography showed the formation of a false aneurysm of a segment artery of the left lower lobe. Immediate interventional therapy was performed by the implantation of two coated coronary stent grafts into the injured pulmonary artery thereby excluding the false aneurysm. Bleeding was stopped by this interventional approach while antegrade blood flow was maintained. Long term follow-up after 3 months showed an effective treatment with a completely thrombotic false aneurysm. However, despite oral anticoagulation and dual antiplatelet therapy, graft patency could not be achieved after 3 months. In summary, implantation of coated stents is a feasible and safe approach for the acute and long term treatment of potentially life-threatening condition of a pulmonary artery false aneurysm while treatment to achieve long term patency of the affected vessel still remains an issue to be resolved.

Endothelial nitric oxide synthase (NOS)3-derived nitric oxide (NO) modulates inotropic response and diastolic interval for optimal cardiac performance under non-inflammatory conditions. In sepsis, excessive NO production plays a key role in severe hypotension and myocardial dysfunction. We aimed to determine the role of NOS3 on myocardial performance, NO production, and time course of sepsis development. NOS3(-/-) and C57BL/6 wildtype mice were rendered septic by cecum ligation and puncture (CLP). Cardiac function was analyzed by serial echocardiography, in vivo pressure and isolated heart measurements. Cardiac output (CO) increased to 160 % of baseline at 10 h after sepsis induction followed by a decline to 63 % of baseline after 18 h in wildtype mice. CO was unaltered in septic NOS3(-/-) mice. Despite the hyperdynamic state, cardiac function and mean arterial pressure were impaired in septic wildtype as early as 6 h post CLP. At 12 h, cardiac function in septic wildtype was refractory to catecholamines in vivo and respective isolated hearts showed impaired pressure development and limited coronary flow reserve. Hemodynamics remained stable in NOS3(-/-) mice leading to significant survival benefit. Unselective NOS inhibition in septic NOS3(-/-) mice diminished this survival benefit. Plasma NO( x )- and local myocardial NO( x )- and NO levels (via NO spin trapping) demonstrated enhanced NO( x )- and bioactive NO levels in septic wildtype as compared to NOS3(-/-) mice. Significant contribution by inducible NOS (NOS2) during this early phase of sepsis was excluded. Our data suggest that NOS3 relevantly contributes to bioactive NO pool in developing sepsis resulting in impaired cardiac contractility.

Background: Transcatheter aortic valve implantation (TAVI) using the Medtronic CoreValve (MCV) system might represent an alternative to conventional redo surgery in older high-risk patients with a failing aortic valve bioprosthesis., Methods and Results: Symptomatic patients with failing aortic valve bioprosthesis, aged ≥65 years with a logistic EuroSCORE ≥10 % were considered for treatment. Local anesthesia was used to retrogradely implant the MCV system into the failing bioprosthetic valve. Clinical events were recorded and a transthoracic echocardiography was performed to evaluate the impact of MCV on hemodynamics after transcatheter aortic valve implantation. A total of 27 patients (aged 74.8±8 years, logistic EuroSCORE of 31±17%) were treated. In those with AS and AS and AR (n=25), the mean gradient declined from 42±16 mm Hg before to 18±8 mm Hg after MCV implantation (P<0.001), in those with AR the level declined by 2. There was no intraprocedural death and no procedural myocardial infarction. On the basis of the definitions of the Valvular Academic Research Consortium, the rate of major stroke was 7.4 %, of life-threatening bleeding 7.4%, of kidney failure stage III 7.4%, and of major access site complication 11.1 %, respectively. Within 30 days after the procedure, 2 patients died; 1 from stroke and 1 from cardiac failure (30-day mortality: 7.4%)., Conclusions: These results suggest that transfemoral mcv implantation into a wide range of degenerated aortic bioprosthetic valves - irrespective of the failure mode - is feasible, safe, and improves hemodynamics in older patients with higher risk for conventional aortic valve redo surgery.

Aims: To characterize the time course of tumor necrosis factor-α (TNF-α) serum levels along with myocardial perfusion and contractile function in patients with ST-segment elevation myocardial infarction (STEMI) and successful primary percutaneous coronary intervention (PCI)., Methods: Serum levels of TNF-α, interleukin 6 (IL-6), and C-reactive protein (CRP) were measured in 42 patients with STEMI before, one and 6 days after successful PCI. Myocardial perfusion was assessed by contrast-enhanced echocardiography (ceEcho), contractile function by unenhanced two-dimensional (2DE) and real-time three-dimensional echocardiography. In a subset of 18 patients, infarct size was quantified by late gadolinium enhancement cardiovascular magnetic resonance imaging (LGE-CMR) on day six., Results: TNF-α serum levels were in the upper normal range within the first 12 h from symptom onset and increased continuously until day six, while IL-6 and CRP increased subsequently with a peak on day one after STEMI. Serum TNF-α on day one after PCI correlated with perfusion defects, wall motion abnormalities, and infarct size (ceEcho: r = 0.52, p = 0.005; 2DE: r = 0.56, p = 0.002; LGE-CMR: r = 0.83-0.86; p < 0.0001). Using multiple regression linear analysis, infarct size on day six was predicted by serum TNF-α 1 day after PCI (p = 0.006, adjusted R (2) 0.638)., Conclusion: Our data reflect the clinical significance of early TNF-α elevation in patients with STEMI and primary PCI (Controlled Clinical Trials number, NCT00529607).

Cell-based therapy is considered a novel and potentially new strategy in regenerative medicine. But the efficacy of cell-based therapy has been limited by the poor survival of the transplanted cells in an ischaemic environment. The goal of the present study is to present a possibility to increase survival of the transplanted cardiomyocytes, by increasing the vascularization of the infarcted area. First, we injected endothelial progenitor cells (EPCs) to augment the vascular density in infarcted areas and to improve the benefit of a subsequent Tx of foetal cardiomyocytes. Serial echocardiography indeed showed significant improvement of the left ventricular function after application of EPC and a significant additive improvement after Tx of foetal cardiomyocytes. In contrast, repetitive EPC transplantation as a control group did not show an additional improvement after the second transplantation. Histologically, cells could be readily detected after Tx by BrdU-staining for EPC and by carboxy-fluorescein diacetate succinimidyl ester (CFSE)-staining for foetal cardiomyocytes. Staining for CD31 revealed a significant increase in vessel density in the infarction area compared with medium controls, possibly contributing to the benefit of transplanted foetal cardiomyocytes. Notably, a significant increase in the number of apoptotic cells was observed in cell-transplanted hearts accompanied by an increase in proliferation, collagen content and neutrophil infiltration, suggesting an active remodelling concomitant with sustained inflammatory processes. In conclusion, repetitive Tx of different cell types after myocardial infarction in rat hearts significantly improved left ventricular function and could represent a feasible option to enhance the benefit of cell therapy., (© 2012 The Authors Journal of Cellular and Molecular Medicine © 2012 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.)

Background: Cardiovascular mortality is markedly increased in chronic kidney disease (CKD) and may be explained in part by sympathetic hyperactivity. Impaired hyperoxic chemoreflex sensitivity (CHRS) has been attributed to an increased sympathetic tone. The aim of the present study was to examine whether chemosensor function is altered in patients with CKD., Methods and Results: We assessed CHRS in 20 patients with stage 3 CKD [glomerular filtration rate (GFR) 30-59 ml/min/1.73 m(2)], in 15 patients with stage 4 CKD [GFR 15-29 ml/min/1.73 m(2)], as well as in 35 age and gender matched patients without any evidence of CKD. The difference in the R-R intervals divided by the difference in the oxygen pressures before and after deactivation of the chemoreceptors by inhalation of pure oxygen was calculated as the CHRS. A CHRS below 3.0 ms/mmHg was defined as pathological. CHRS was significantly depressed in patients with stage 3 CKD (2.9 ± 0.9 ms/mmHg, P=0.005) and in patients with stage 4 CKD (2.1 ± 0.6 ms/mmHg, P<0.001), as compared with patients without CKD (6.7 ± 0.9 ms/mmHg). There was a negative correlation between serum creatinine and CHRS (r=-0.51; P<0.001). In patients with CKD, chemosensor deactivation decreased mean arterial pressure from 91 ± 4 mmHg to 87 ± 3 mmHg (P=0.03). Multivariate analysis showed that GFR (P=0.001) was the only independent predictor of a pathological CHRS., Conclusion: Using a relatively non-invasive bedside test we provide evidence for a blunted peripheral chemosensor function in chronic kidney disease. We thereby lay the basis for interventional studies assessing chemosensor function in chronic kidney disease., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Introduction: As yet, murine aortic grafts have merely been monitored histopathologically. The aim of our study was to examine how these grafts can be monitored in vivo and non-invasively by using high-resolution ultrasound microimaging to evaluate function and morphology. A further aim was to prove if this in vivo monitoring can be correlated to immunohistological data that indicates graft integrity., Methods: Murine infrarenal aortic isografts were orthotopically transplanted into 14 female mice (C57BL/6-Background) whereas a group of sham-operated animals (n = 10) served as controls. To assess the graft morphology and hemodynamics, we examined the mice over a post-operative period of 8 weeks with a sophisticated ultrasound system (Vevo 770, Visual Sonics)., Results: The non-invasive graft monitoring was feasible in all transplanted mice. We could demonstrate a regular post-transplant graft function and morphology, such as anterior/posterior wall displacement and wall thickness. Mild alterations of anterior wall motion dynamics could only be observed at the site of distal graft anastomosis (8 weeks after grafting (transplant vs. sham mice: 0.02 mm ± 0.01 vs. 0.03 mm ± 0.01, p<0.05). However, the integrity of the entire graft wall could be confirmed by histopathological evaluation of the grafts., Conclusions: With regard to graft patency, function and morphology, high resolution ultrasound microimaging has proven to be a valuable tool for longitudinal, non-invasive, in vivo graft monitoring in this murine aortic transplantation model. Consequently, this experimental animal model provides an excellent basis for molecular and pharmacological studies using genetically engineered mice., (Crown Copyright © 2011. Published by Elsevier Ireland Ltd. All rights reserved.)

Objectives: Here we assess the intrinsic functions of the chemokine receptor CXCR4 in remodeling after myocardial infarction (MI) using Cxcr4 heterozygous (Cxcr4(+/-)) mice., Background: Myocardial necrosis triggers complex remodeling and inflammatory changes. The chemokine CXCL12 has been implicated in protection and therapeutic regeneration after MI through recruiting angiogenic outgrowth cells, improving neovascularization and cardiac function, but the endogenous role of its receptor CXCR4 is unknown., Methods: MI was induced by ligation of the left descending artery. Langendoff perfusion, echocardiography, quantitative immunohistochemistry, flow cytometry, angiogenesis assays, and cardiomyocyte analysis were performed., Results: After 4 weeks, infarct size was reduced in Cxcr4(+/-) mice compared with wild-type mice and in respective bone marrow chimeras compared with controls. This was associated with altered inflammatory cell recruitment, decreased neutrophil content, delayed monocyte infiltration, and a predominance of Gr1(low) over classic Gr1(high) monocytes. Basal coronary flow and its recovery after MI were impaired in Cxcr4(+/-)mice, paralleled by reduced angiogenesis, myocardial vessel density, and endothelial cell count. Notably, no differences in cardiac function were seen in Cxcr4(+/-)mice compared with wild-type mice. Despite defective angiogenesis, Cxcr4(+/-) mouse hearts showed no difference in CXCL12, vascular endothelial growth factor or apoptosis-related gene expression. Electron microscopy revealed lipofuscin-like lipid accumulation in Cxcr4(+/-) mouse hearts and analysis of lipid extracts detected high levels of phosphatidylserine, which protect cardiomyocytes from hypoxic stress in vitro., Conclusions: CXCR4 plays a crucial role in endogenous remodeling processes after MI, contributing to inflammatory/progenitor cell recruitment and neovascularization, whereas its deficiency limits infarct size and causes adaptation to hypoxic stress. This should be carefully scrutinized when devising therapeutic strategies involving the CXCL12/CXCR4 axis., (Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Desmosomes are cell-cell adhesion sites and part of the intercalated discs, which couple adjacent cardiomyocytes. The connection is formed by the extracellular domains of desmosomal cadherins that are also linked to the cytoskeleton on the cytoplasmic side. To examine the contribution of the desmosomal cadherin desmoglein 2 to cardiomyocyte adhesion and cardiac function, mutant mice were prepared lacking a part of the extracellular adhesive domain of desmoglein 2. Most live born mutant mice presented normal overall cardiac morphology at 2 weeks. Some animals, however, displayed extensive fibrotic lesions. Later on, mutants developed ventricular dilation leading to cardiac insufficiency and eventually premature death. Upon histological examination, cardiomyocyte death by calcifying necrosis and replacement by fibrous tissue were observed. Fibrotic lesions were highly proliferative in 2-week-old mutants, whereas the fibrotic lesions of older mutants showed little proliferation indicating the completion of local muscle replacement by scar tissue. Disease progression correlated with increased mRNA expression of c-myc, ANF, BNF, CTGF and GDF15, which are markers for cardiac stress, remodeling and heart failure. Taken together, the desmoglein 2-mutant mice display features of dilative cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy, an inherited human heart disease with pronounced fibrosis and ventricular arrhythmias that has been linked to mutations in desmosomal proteins including desmoglein 2.

Objectives: This study sought to characterize the impact of hemodialysis (HD)-induced release of hemoglobin on the bioavailability of nitric oxide (NO) and endothelial function., Background: Patients on chronic HD suffer from endothelial dysfunction and a massively increased risk for cardiovascular events. Although dialysis-dependent and -independent factors are discussed, the exact mechanisms are not fully understood., Methods: In 14 HD patients (56+/-15 years of age), endothelial function was determined by measuring flow-mediated dilation (FMD) of the brachial artery using high-resolution ultrasound before and after treatment. The NO consumption activity of plasma isolated from patients before and after hemodialysis was studied with an NO-sensitive electrode., Results: HD impaired FMD (3.5+/-2.6% to 1.7+/-1.4%, p=0.04) without affecting brachial artery diameter (4.7+/-0.6 mm vs. 4.4+/-0.9 mm, p=0.27). This was accompanied by an increase in cell-free plasma hemoglobin (196+/-43 mg/l to 285+/-109 mg/l, p=0.01), which led to a decrease in the bioavailability of free NO by more than 70%. Oxidation of the released plasma ferrous hemoglobin prevented the consumption of NO. The amount of decompartmentalized hemoglobin after HD correlated inversely with the change in FMD (r=-0.65, p=0.041)., Conclusions: Our data support a role of HD-induced release of hemoglobin in the pathogenesis of endothelial dysfunction in patients with end-stage renal disease. Approaches that oxidize free plasma hemoglobin may restore NO bioavailability and may have potential beneficial effects on vascular function. (Influence of Hemodialysis on Endothel-Depending Dilatation of Peripheral Arteries; NCT00764192)., (Copyright (c) 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to investigate the effect of diagnostic transradial catheterization on vascular function of upstream brachial artery (BA)., Background: The transradial access has recently become an alternative to transfemoral cardiac catheterization. A potential caveat of this approach lies in possible sustained physical radial artery (RA) damage., Methods: We studied 30 patients (age 61 +/- 11 years) undergoing diagnostic coronary angiography with the transradial access (5-F). Endothelium-dependent, flow-mediated vasodilation (FMD) was measured before and at 6 and 24 h after catheterization of the right-sided RA and BA with high-resolution ultrasound. The left-sided RA served as a control., Results: Transradial catheterization significantly decreased FMD in the RA (overall mean 8.5 +/- 1.7% to 4.3 +/- 1.6%) and the upstream BA (overall mean 4.4 +/- 1.6% to 2.9 +/- 1.6%) at 6 h. Subgroup analysis showed that FMD of both arteries at 6 h was significantly lower in active smokers and that it only remained impaired at 24 h in this group, whereas nonsmoker FMD fully recovered. The degree of BA but not RA FMD dysfunction was related to the number of catheters used, with no change after 2 catheters, 1.9 +/- 1.2% decrease (6 h) and recovery (24 h) after 3 catheters, and 3.9 +/- 1.2% decrease (6 h) without recovery (24 h) after 4 to 5 catheters. The RA dysfunction correlated with the baseline diameter. The contralateral control RA exhibited no change ruling out systemic effects., Conclusions: Transradial catheterization not only leads to dysfunction of the RA but also the upstream BA, which is more severe and sustained in smokers and with increasing numbers of catheters.

As a novel and promising therapeutic strategy for heart failure, the application of different cell types is the subject of increasing research interest. In this study we investigated the effect of several cell types and microspheres (uniform polystyrene microspheres, 10 microm diameter) transplanted 4 weeks after induction of myocardial infarction in a rat model. Eight weeks after intramyocardial application of fibroblasts and microspheres, left ventricular function was significantly improved as demonstrated by isolated heart studies (Langendorff) and echocardiographic findings (LVDP fibroblasts 129 +/- 32.9 mmHg, LVDP microspheres 119.2 +/- 24.1 mmHg, fractional shortening (FS) microspheres 38.9 +/- 4.6%, FS fibroblasts 36.84 +/- 6.05%) in contrast to injection of macrophages or medium alone (LVDP medium 67 +/- 22.6 mmHg, LVDP macrophages 75.9 +/- 24.8 mmHg, FS macrophages 29.16 +/- 8.7%, FS medium 27.2 +/- 7.2%, P < 0.05). Signals of Bromodesoxy-Uridine (BrdU) labeled transplanted fibroblasts were detected in infarcted areas. Microspheres were recorded abundantly by autofluorescence. Significantly more apoptotic cells were observed in infarcted areas of macrophage (328.6 +/- 37.4 cells/mm(2)) and medium (338.7 +/- 16.5 cells/mm(2); P < 0.05) treated hearts compared to microsphere (233.2 +/- 16.8 cells/mm(2)) and fibroblast (232.2 +/- 19.1 cells/mm(2)) injected hearts. Neovascularization, as reflected by the density of CD 31 positive vessels in the infracted area, did not differ between the four groups studied. The increased number of macrophages in infarcted areas after fibroblast and microsphere injection (fibroblasts 94.7 +/- 7.1 cells/mm(2), microspheres 82.2 +/- 3.0 cells/mm(2), macrophages 56.02 +/- 9.93 cells/mm(2), medium 46.35 +/- 9.03 cells/mm(2), P < 0.05) suggests that the underlying mechanism of augmented left ventricular function might be based on inflammatory processes.

The nitrite anion is reduced to nitric oxide (NO*) as oxygen tension decreases. Whereas this pathway modulates hypoxic NO* signaling and mitochondrial respiration and limits myocardial infarction in mammalian species, the pathways to nitrite bioactivation remain uncertain. Studies suggest that hemoglobin and myoglobin may subserve a fundamental physiological function as hypoxia dependent nitrite reductases. Using myoglobin wild-type ((+/+)) and knockout ((-/-)) mice, we here test the central role of myoglobin as a functional nitrite reductase that regulates hypoxic NO* generation, controls cellular respiration, and therefore confirms a cytoprotective response to cardiac ischemia-reperfusion (I/R) injury. We find that myoglobin is responsible for nitrite-dependent NO* generation and cardiomyocyte protein iron-nitrosylation. Nitrite reduction to NO* by myoglobin dynamically inhibits cellular respiration and limits reactive oxygen species generation and mitochondrial enzyme oxidative inactivation after I/R injury. In isolated myoglobin(+/+) but not in myoglobin(-/-) hearts, nitrite treatment resulted in an improved recovery of postischemic left ventricular developed pressure of 29%. In vivo administration of nitrite reduced myocardial infarction by 61% in myoglobin(+/+) mice, whereas in myoglobin(-/-) mice nitrite had no protective effects. These data support an emerging paradigm that myoglobin and the heme globin family subserve a critical function as an intrinsic nitrite reductase that regulates responses to cellular hypoxia and reoxygenation [corrected]

Nitric oxide (NO), one of the most important vascular signaling molecules, is primarily produced by endothelial NO synthase (eNOS). eNOS is tightly regulated by its substrate l-arginine, cofactors and diverse interacting proteins. Interestingly, an NO synthase (NOS) was described within red blood cells (RBC NOS), and it was recently shown to significantly contribute to the intravascular NO pool and to regulate physiologically relevant mechanisms. However, the regulatory mechanisms and clinical implications of RBC NOS are unknown. The aim of this review is to highlight intracellular RBC NOS interactions and the role of RBC NOS in RBC homeostasis. Furthermore, macro- and microvascular diseases affected by RBC-derived NO are discussed.

Nitrite plays an eminent role in cardiovascular physiology and pathology, mediating hypoxic vasodilation, reducing ischemia-reperfusion injury, and regulating cardiac energetics and function. The role of circulating nitrite in critically ill patients has not been examined so far. To investigate whether whole blood nitrite can be determined reproducibly in an intensive care setting, 30 patients from a cardiology intensive care unit were enrolled in this study, no matter what the underlying disease. Blood was drawn from an arterial catheter and whole blood nitrite was determined, using a tri-iodide/ozone-based chemiluminescence assay after incubation with a ferricyanide-containing stabilization solution. Whole blood nitrite levels ranged from 35 to 1193 nmol/L (mean+/-SEM: 220+/-20 nmol/L). Myocardial infarction was associated with lower whole blood nitrite levels (200+/-53 nmol/L for elevated serum CK MB levels vs 432+/-95 nmol/L in the normal CK MB range, p=0.039). Neither impaired kidney function nor an inflammatory state was associated with higher or lower whole blood nitrite levels. In conclusion, whole blood nitrite can be measured easily and reproducibly in critically ill patients, regardless of renal function and inflammation. The origin of decreased nitrite levels in myocardial infarction is currently unclear and needs to be further elucidated.

Age-dependent alterations of the vessel wall may predispose older individuals to increased cardiovascular pathology. Aging is associated with an impaired bioactivity of nitric oxide (NO). Plasma nitrite reflects NO-synthase activity under fasting conditions and is an important storage pool of NO. To test the hypothesis that aging is associated with an impaired capacity of the vasculature to increase plasma nitrite during exercise, 29 young and 28 old healthy individuals (25 +/- 1 years and 58 +/- 2 years; P < 0.001) without major cardiovascular risk factors were enrolled. Exercise stress was similar in both groups. Baseline nitrite did not differ (107 +/- 8 vs. 82 +/- 10 nmol/l, young vs. old; n.s.) although a trend toward higher nitrite levels in young individuals was seen. In young subjects, exercise increased plasma nitrite by 38 +/- 7% (P < 0.001) compared to only 13 +/- 8% (P = n.s.) in older subjects. L-NMMA blocked increases of nitrite. Endothelial function, as defined by flow-mediated-dilation (FMD) of the brachial artery via ultrasound, was impaired in older subjects (5.4 +/- 0.4% vs. 6.7 +/- 0.3%; P < 0.01). Multivariate analysis showed that age (P = 0.007), BMI (P = 0.010), and LDL (P = 0.021) were independent predictors of nitrite increase. The fact that aging is associated with an impaired capacity of the vasculature to adequately increase nitrite to physiological stimuli may contribute to attenuated maintenance and further deterioration of vascular homeostasis with aging.

Myocardial necrosis triggers inflammatory changes and a complex cytokine cascade that are only incompletely understood. The chemokine receptor CCR1 mediates inflammatory recruitment in response to several ligands released by activated platelets and up-regulated after myocardial infarction (MI). Here, we assess the effect of CCR1 on remodelling after MI using Ccr1-deficient (Ccr1(-)(/-)) mice. MI was induced in Ccr1(-/-) or wild-type mice by proximal ligation of the left anterior descending (LAD). Mice were sacrificed and analysed at day 1, 4, 7, 14 and 21 after MI. While initial infarct areas and areas at risk did not differ between groups, infarct size increased to 20.6+/-8.4% of the left ventricle (LV) in wild-type mice by day 21 but remained at 11.2+/-1.2% of LV (P<0.05) in Ccr1(-/-) mice. This attenuation in infarct expansion was associated with preserved LV function, as analysed by isolated heart studies according to Langendorff. Left ventricular developed pressure was 84.5+/-19.8 mmHg in Ccr1(-/-) mice compared to 49.0+/-19.7 mmHg in wild-type mice (P<0.01) and coronary flow reserve was improved in Ccr1(-/-) mice. An altered post-infarct inflammatory pattern was observed in Ccr1(-/-) mice characterized by diminished neutrophil infiltration, accelerated monocyte/lymphocyte infiltration, decreased apoptosis, increased cell proliferation and earlier myofibroblast population in the infarcted tissue. In conclusion, functional impairment and structural remodelling after MI is reduced in the genetic absence of Ccr1 due to an abrogated early inflammatory recruitment of neutrophils and improved tissue healing, thus revealing a potential therapeutic target.

Cell transplantation has recently emerged as a novel therapy for ischemic heart disease. The presented study investigated the effect of intramyocardial transfer of human endothelial progenitor cells (EPCs) and stromal-cell derived factor-1alpha (SDF-1alpha) on left ventricular function in a chronic setting after myocardial infarction in cyclosporine treated rats. BrdU-labeled EPCs (10(6)), 10 microg SDF-1alpha, EPCs+SDF-1alpha or placebo medium were injected directly into the border infarct zone 4 weeks after acute myocardial infarction. Eight weeks after transplantation, echocardiography identified significantly improved fractional shortening after EPC or EPCs+SDF-1alpha injection as compared with injection of placebo medium. Investigating isolated hearts revealed a significant increase in left ventricular developing pressure after transplantation of SDF-1alpha or EPCs+SDF-1alpha. Furthermore, coronary flow rates were significantly elevated, especially after transplantation of EPCs+SDF-1alpha (under catecholamine stress 24.2 +/- 1.55 ml/min vs. 13.1 +/- 1 ml/min in the control) correlating with increased density of CD31+ vessel structures in the EPC as well as EPCs+SDF-1alpha groups, thus defining a higher rate of neovascularization. Notably, SDF-1alpha injected hearts showed only a trend towards improvement in coronary flow. BrdU+ signals were detected in infarct areas, partially integrating into vascular networks. The rate of apoptotic cells as well as the amount of inflammatory cells was significantly elevated in the placebo control group. In conclusion, transplantation of EPCs as well as EPCs+SDF-1alpha associated with improvement in cardiac function after infarction, which was attributable to enhanced neovascularization and decreased inflammation. These results imply a combined benefit of EPCs+SDF-1alpha in the treatment of myocardial infarction.

Sepsis is generally viewed as a disease aggravated by an inappropriate immune response encountered in the afflicted individual. As an important organ system frequently compromised by sepsis and always affected by septic shock, the cardiovascular system and its dysfunction during sepsis have been studied in clinical and basic research for more than 5 decades. Although a number of mediators and pathways have been shown to be associated with myocardial depression in sepsis, the precise cause remains unclear to date. There is currently no evidence supporting global ischemia as an underlying cause of myocardial dysfunction in sepsis; however, in septic patients with coexistent and possibly undiagnosed coronary artery disease, regional myocardial ischemia or infarction secondary to coronary artery disease may certainly occur. A circulating myocardial depressant factor in septic shock has long been proposed, and potential candidates for a myocardial depressant factor include cytokines, prostanoids, and nitric oxide, among others. Endothelial activation and induction of the coagulatory system also contribute to the pathophysiology in sepsis. Prompt and adequate antibiotic therapy accompanied by surgical removal of the infectious focus, if indicated and feasible, is the mainstay and also the only strictly causal line of therapy. In the presence of severe sepsis and septic shock, supportive treatment in addition to causal therapy is mandatory. The purpose of this review is to delineate some characteristics of septic myocardial dysfunction, to assess the most commonly cited and reported underlying mechanisms of cardiac dysfunction in sepsis, and to briefly outline current therapeutic strategies and possible future approaches.

Background: Raised concentrations of endotoxin (lipopolysaccharides, LPS) have been demonstrated in patients with chronic heart failure (CHF). Tolerance of monocytes to LPS can be induced by negative feedback mechanism through LPS itself, resulting in a downregulation of cytokine response to LPS challenge. As endotoxin desensitization has also been suggested for CHF, we investigated the response to LPS challenge in CHF patients., Methods: We prospectively studied 100 patients with CHF (62 +/- 13 years) and 21 controls (58 +/- 10 years, LVEF 60 +/- 3%). HLA-DR expression and TNFalpha generation of monocytes after ex vivo stimulation by LPS (stimulation with LPS 50 and 500 pg/ml) were determined. 46 CHF patients were in NYHA class II (LVEF 29 +/- 8%) and 54 in NYHA class III (LVEF 27 +/- 7%)., Results: HLA-DR expression in controls (25,837 +/- 7915 ABS/cell) was comparable to CHF NYHA II patients (23,720 +/- 8488 ABS/cell, n.s.), but lower in patients classified NYHA III (20,327 +/- 5073 ABS/cell, p < 0.01). Stimulated TNFalpha production ex vivo was higher in CHF NYHA III (LPS 50: 437 +/- 284; LPS 500: 946 +/- 500 pg/ml, each p < 0.05) and CHF NYHA II (LPS 50: 397 +/- 277; LPS 500: 933 +/- 483 pg/ml, each p < 0.05) compared to controls (LPS 50: 315 +/- 134; LPS 500: 715 +/- 339 pg/ml)., Conclusions: In chronic heart failure TNFalpha generation capacity increases while HLA-DR expression decreases compared to controls. Thus patients with CHF display enhanced susceptibility to inflammatory stimuli.

Background: A peak VO2 above 14 ml/min/kg at cardiopulmonary exercise testing and brain natriuretic peptide (BNP) levels is used to estimate survival in patients with chronic heart failure (CHF). Limited data, however, exist comparing the prognostic value of both markers simultaneously in patients with mild to moderate CHF., Methods: We prospectively studied 85 consecutive patients (59+/-13 years, 63 men) with CHF (mean LVEF 26+/-6%). All patients underwent cardiopulmonary exercise testing with determination of peak VO2 and measurement of plasma BNP at rest. The incidence of cardiac decompensation and cardiac death was recorded in the follow-up., Results: During a mean follow-up of 427+/-150 days, four deaths and ten cardiac decompensations occurred. Kaplan-Meier estimates of freedom from clinical events differed significantly for patients above and below the median BNP of 292 pg/ml and also for patients above and below a peak VO2 of 14 ml/min/kg (p<0.05 each). BNP and peak VO2 (area under the ROC 0.75 vs. 0.72) showed a comparable discrimination of CHF patients with adverse cardiac events. The prognostic information of BNP was at least as powerful as that derived from peak VO2. A BNP above 324 pg/ml was associated with a risk ratio of 8.8 for adverse cardiac events., Conclusions: In patients with mild to moderate CHF, BNP measurements appear to be an alternative to peak VO2 determined by cardiopulmonary exercise testing for the assessment of prognosis in CHF. BNP may facilitate the ambulatory management of patients with mild to moderate CHF since it is less expensive, less time-consuming, and free of procedural risk compared to exercise testing.