Transcatheter aortic valve replacement for severe aortic stenosis can improve long-term survival of nonagenarians as compared to an age- and sex-matched general population.

BACKGROUND: Nonagenarians are at increased risk for morbidity and mortality after transcatheter aortic valve replacement (TAVR) based solely on their age. The aim of our study was to evaluate survival of nonagenarians with severe aortic valve stenosis (AS) after TAVR as compared to an age- and sex-matched general population. METHODS: From 2009 to 2017, 1052 consecutive patients ≥80 years scheduled for TAVR were included. Patients were divided into three groups depending on their age at the time of the procedure: 80-84 (Group 1), 85-89 (Group 2) and ≥90 years (Group 3). Survival of patients treated with TAVR was compared to the life expectancy of an age- and sex-matched cohort in the general population. RESULTS: Nonagenarians were more likely to experience major access-site complications than their younger counterparts (7.6% Group 1 vs. 10.1% Group 2 vs. 17.6% Group 3, p=0.016). One-year mortality in nonagenarians was higher as compared to the general population (27.8% vs. 20.0%). After two years, the mortality curves between the TAVR patients and the general population converged (39.2% vs. 37.5%) and were lower after five years. CONCLUSIONS: During the observation period of five years, carefully selected nonagenarians treated with TAVR had at least the same mortality rate as an age- and sex-matched general population after two years despite procedure-associated complications. The negative prognostic impact of the severe AS was completely eliminated by TAVR.

Transfemoral versus transapical transcatheter aortic valve implantation: a single-centre experience.

OBJECTIVES: Transapical transcatheter aortic valve implantation (TAVI) is associated with increased mortality as compared to the transfemoral (TF) access. Possible mechanisms include different patient risk profiles as well as an intrinsic injury caused by the access route itself. METHODS: All consecutive patients scheduled for TAVI between January 2009 and June 2016 at a single centre were evaluated. A comparison of 30-day mortality and morbidity rates for patients undergoing TF or transapical (TA) TAVI was performed according to the criteria of the Valve Academic Research Consortium 2. RESULTS: During the investigated period, 1130 patients (TF: n = 619, TA: n = 511) were scheduled for TAVI. TA patients had a higher operative risk profile (logistic EuroSCORE: 24% vs 17%; P < 0.001). Unadjusted 30-day mortality rate was higher in TA than in TF patients, albeit this difference was not significant [TA: 6.7%, TF: 4.8%; odds ratio (OR) 1.3 (0.8-2.3); P = 0.216]. The multivariate logistic regression analysis revealed the logistic EuroSCORE and institutional experience, but not the access mode as independent predictors of 30-day mortality. Major access-site complications occurred with a similar frequency in both groups [TA: 9.4%; TF: 9.2%; OR 1.02 (0.68-1.53); P = 0.915]. Unadjusted long-term mortality rate was higher after TA TAVI. After adjustment, the Cox regression analysis revealed similar long-term mortality rates after TF and TA TAVI [hazard ratio 1.1 (0.88-1.36)]. CONCLUSIONS: The increased mortality of patients undergoing TA TAVI is associated with the patient risk profile and the institutional experience but not with the access mode itself.

Left ventricular ejection fraction of < 20%: Too bad for MitraClip© ?

OBJECTIVES: This study sought to investigate whether the percutaneous mitral regurgitation (MR) reduction with the MitraClip® system in end-stage heart failure patients with a left ventricular ejection fraction (LVEF) of <20% also effects beneficial outcome or whether the underlying myogenic problem is leading and therefore of prognostic relevance. BACKROUND: The interventional treatment of functional mitral regurgitation (FMR) with the MitraClip® system could improve the clinical and hemodynamic outcome in patients with severely impaired left ventricular function. MATERIALS AND METHODS: Between 2011 and 2016, a total of 147 patients with FMR were treated with MitraClip® at our institution. The cohort was divided into two groups: LVEF ≥ 20% (N = 126) and <20% (N = 21). Follow-up assessments included exercise capacity, 6-min walk test, probrain natriuretic peptide-measurement (ProBNP), echocardiography and right heart catheterization. Only three patients with an LVEF ≥ 20% and one patient with an LVEF < 20% were lost for follow-up. RESULTS: In the vast majority of patients, a reduction from severe to mild MR was demonstrated with no difference between both groups (P = 0.422). At follow-up, both subgroups experienced similar improvements in exercise capacity and hemodynamics. Patients with an LVEF < 20% were on average 5.8 years younger, while mortality rates were comparable in both groups (P = 0.760). CONCLUSION: By careful selection, even patients in the end stage of advanced LV dysfunction as the result of the underlying myogenic problem and the additional harmful effects of the high volume loading due to the FMR can exhibit significant clinical and hemodynamic improvement after MitraClip© therapy.

Impact of right and left ventricular systolic dysfunction on perioperative outcome and long-term survival after transcatheter aortic valve replacement.

BACKGROUND: Aim of the study was to determine the impact of right- and left-ventricular systolic dysfunction on perioperative outcome and long-term survival after TAVR. METHODS: Study population consisted of 702 TAVRs between 2009 and 2014, 345 by TF, 357 by TA route. RV and LV function were determined by TAPSE and LVEF measurement during baseline echocardiography. Patients were divided according to TAPSE (>18 mm/14-18 mm/<14 mm) and LVEF (>50%/30-50%/<30%) tertiles. Outcome at day-30 and Kaplan-Meier 4-year survival were analyzed. RESULTS: Impaired RV and LV-function did not adversely affect mortality, stroke, bleeding, and vascular-complications at 30 days. Patients with TAPSE < 14 mm displayed elevated rate of renal failure requiring dialysis (11%; P < 0.01). Kaplan-Meier survival was adversely affected by RV-systolic dysfunction RVSD (P < 0.01). Multivariate analysis revealed that impaired RVSD but not LVSD was an independent determinant for late mortality (hazard ratio TAPSE 14-18 mm: 1.53; P = 0.02; TAPSE <14 mm: 2.12; P < 0.01). CONCLUSIONS: Peri-operative mortality and risk of stroke after TAVR are not adversely affected by preexisting RV or LV dysfunction. Long-term survival is impaired in patients with RVSD. RVSD but not LVSD is an independent risk factor for late mortality. TAVR should be the preferred therapy for patients with RVSD and LVSD, especially when patient is suitable for TF.

Drug Coated Balloon Is Less Effective for Treatment of DES In-Stent Restenosis Both in Native Coronary Arteries and Saphenous Vein Grafts: Results From a Bicenter Registry.

BACKGROUND: The paclitaxel drug coated balloon (DCB) is an established treatment for bare metal stent (BMS) in-stent restenosis (ISR) in native coronary arteries. The evidence of DCB-application for drug eluting stent (DES) ISR both in native coronaries and saphenous vein grafts (SVG) is limited. Aim of our study was to compare the differential efficacy of DCB for treatment of BMS- and DES-ISR in native coronary vessels and SVGs. METHODS AND RESULTS: N = 135 DCB-treated patients with available follow up (FU) angiography were included in this retrospective study. Patients received treatment between April 2009 and March 2013 at 2 tertiary care hospitals in Germany. DCB was applied in BMS-ISR (n = 65; 48%) and DES-ISR (n = 70; 52%). DCB-treated lesions were located in native coronary arteries (n = 110; 81%; BMS-ISR: n = 58; 53%; DES-ISR: n = 52; 47%) and SVGs (n = 25; 19%; BMS-ISR: n = 7, 28%; DES-ISR: n = 18, 72%). Median FU was 12 months. Endpoints were binary restenosis and target lesion revascularization (TLR). Binary restenosis (29% vs. 57%; P < 0.01) and TLR (18% vs. 46%; P < 0.01) were significantly more frequent in DES-ISR versus BMS-ISR. In SVGs, TLR was required in 72% (DES-ISR) versus 14% (BMS-ISR); P = 0.02. In the Kaplan-Meier-analysis freedom from both endpoints was significantly decreased in the DES-lesions both in the total population (binary restenosis P < 0.01; TLR P < 0.01) and native coronaries (binary restenosis P = 0.02; TLR P = 0.04). CONCLUSIONS: DCB treatment is less effective in DES-ISR than in BMS-ISR. The diminished efficacy of DCB treatment is even more pronounced in DES-ISR located within degenerated SVGs.

Association between left atrial low-voltage area, serum apoptosis, and fibrosis biomarkers and incidence of silent cerebral events after catheter ablation of atrial fibrillation.

BACKGROUND: Silent cerebral events (SCE) have been identified on cerebral diffusion-weighted cerebral magnetic resonance imaging (DE-MRI) after catheter ablation (CA) of atrial fibrillation (AF). The purpose of this study was to investigate the impact of atrial remodeling on the incidence of SCE after AF CA. METHODS: Forty patients (67.8 ± 10 years, 47.5 % women) with symptomatic paroxysmal (n = 11, 27.5 %) or persistent AF undergoing AF CA were prospectively enrolled. LA fibrosis was estimated by intraprocedural bipolar voltage mapping in sinus rhythm. Apoptosis-stimulating fragment (Fas-Ligand) and amino terminal peptide from collagen III (PIIINP) concentrations were analyzed of LA and femoral vein blood. Cerebral DE-MRI was performed 1 to 2 days after CA of AF for detection of SCE. In nine patients (22.5 %), new SCE were detected on DE-MRI after AF CA. RESULTS: Patients with SCE had higher CHA2DS2-VASc score, larger left atrial diameter (LADmax), and higher surface area of left atrial low-voltage (24 ± 11.2 vs 3.5 ± 4.2 %, p < 0.0001). Concentrations of peripheral PIIINP (103.7 ± 25.9 vs 81.8 ± 16.7 pg/ml, p < 0.01) and Fas-Ligand (124.1 ± 22.4 vs 87.6 ± 19.4 pg/ml, p < 0.01) were significantly higher in patients with SCE and correlated to low-voltage surface area (p < 0.01). Multivariable logistic regression analysis revealed peripheral Fas-Ligand, LADmax, CHA2DS2-Vasc score, and LA low-voltage area proportion to be independent predictors for the development of SCE. CONCLUSIONS: LA remodeling, estimated by LADmax and LA low-voltage area, has significant relationship with the risk of SCE after AF ablation. Moreover, Fas-Ligand may act as an independent predictor for SCE in the context of AF CA.

Concomitant coronary intervention is associated with poorer early and late clinical outcomes in selected elderly patients receiving transcatheter aortic valve implantation.

OBJECTIVES: Significant coronary artery disease (CAD) is common among patients currently evaluated for transcatheter aortic valve implantation (TAVI). Limited data exist on the outcome of patients undergoing combined transcatheter treatment of aortic valve disease and CAD. The aim of the study was to analyse the impact of concomitant percutaneous coronary intervention (PCI) on early and late clinical outcomes of patients receiving TAVI. METHODS: TAVIs were performed through either transfemoral or transapical access using SAPIEN (XT), CoreValve or AcurateTA valves. PCI was decided by the interdisciplinary heart team and performed synchronously or as a staged procedure upfront. Standardized valve academic research consortium (VARC)-2 endpoints were used. In case of a staged approach, TAVI was defined as the index procedure. Thirty-day outcomes and Kaplan-Meier 2-year survival were analysed. RESULTS: Of 411 TAVIs, 65 (16%) received PCI. Mean age was 82 years (P = 0.92) and mean logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 21.7% (TAVI + PCI) and 20.3% (TAVI; P = 0.47). PCI was performed as staged procedure upfront (74%) or synchronously (26%). In 95% of PCIs, a single coronary artery was treated, and 71% received bare metal stents. Incidence of myocardial infarction (6 vs 1%; P = 0.01) and 30-day mortality (15 vs 5%; P = 0.01) were higher in the TAVI + PCI group, compared with the TAVI group. Synchronous (18%) vs staged (15%) approach for PCI had comparable early mortality (P = 1.0). Kaplan-Meier 2-year survival was poorer in the TAVI + PCI group (P = 0.03) with an odds ratio of 1.66 (P = 0.04). CONCLUSIONS: Concomitant PCI is--when based on current heart team practice--associated with increased early and late mortality in selected elderly patients undergoing TAVI.

Emergency cardiac surgery during transfemoral and transapical transcatheter aortic valve implantation: incidence, reasons, management, and outcome of 411 patients from a single center.

OBJECTIVES AND BACKGROUND: Transcatheter aortic valve implantation (TAVI) is increasingly performed in high-risk patients with severe aortic valve stenosis. Incidence and impact of emergency cardiac surgery (ECS) during TAVI is unclear. METHODS AND RESULTS: Two-hundred twenty one transapical (TA) and 190 transfemoral (TF) TAVIs were performed at our hospital between 01/2009 and 12/2012. Twenty patients (4.9%) required ECS, more frequently in the TF- (n = 11; 5.8%) than in the TA-group (n = 9; 4.1%; P = 0.017). ECS-cases were evenly distributed throughout the 4 years. Baseline characteristics of the ECS-patients were not different from the non-ECS-patients. Reasons were acute cardiac failure, coronary obstruction, annular rupture, valve migration, right- and left-ventricular perforation, severe paravalvular leakage, aortic dissection, and mitral valve damage. Surgical intervention consisted of peripheral CPB, switch to TA, thoracotomy and suture of perforated cardiac chambers and conventional aortic valve replacement with concomitant repair of associated cardiovascular injury. Thirty-day mortality was 35.0%, and 55.0% could be salvaged to hospital discharge. Kaplan-Meier 1-year survival curves were significantly impaired for patients requiring ECS (TF: P < 0.0001, HR 8.716; TA: P = 0.013, HR 2.813). CONCLUSIONS: Life-threatening complications requiring bail-out ECS occur in a substantial proportion during TAVI. ECS dramatically affects early and late outcome after TAVI. Under optimal conditions more than half of the ECS-patients can be salvaged. With the current technology of THV-systems ECS should be an integral part of the logistic conditions surrounding TAVI and is far from being futile in this patient population.

Simple, effective and safe vascular access site closure with the double-ProGlide preclose technique in 162 patients receiving transfemoral transcatheter aortic valve implantation.

OBJECTIVES: Aim of this study was to analyze feasibility, efficacy, and safety of a double-ProGlide preclose technique for access site closure after transfemoral transcatheter aortic valve implantation (TAVI). BACKGROUND: An effective and safe transcutaneous closure device is advantageous in transfemoral TAVI to avoid surgical cut down of the large caliber sheath insertion site. The use of two ProGlide sutures has not been described in this context in a large patient cohort. METHODS: ProGlide closure was used between 2010 and 2012 in 162 patients. ProGlide sutures were deployed in a preclose technique prior to insertion of the large caliber sheath. Success of the closure technique was defined as effective hemostasis and no further access site-related vascular or bleeding complications during the index hospitalization. RESULTS: Patients were 82 ± 5 years old with a logistic EuroSCORE of 16.7 ± 12.5. Edwards SAPIEN valves were used in 81.5% and Medtronic CoreValves in 18.5%. The overall success rate of the double-ProGlide technique was 93.9%. Success rate was only 40.0% under circumstances of prolonged high-dose heparinization. Success rate was 96.8% among the patients on dual-antiplatelet therapy (DAPT). All 10 ProGlide failures could effectively be managed by either percutaneous angioplasty or surgical reconstruction. The rate of VARC major vascular complications was 4.3%. Thirty-day mortality was 5.6%. CONCLUSION: The double-ProGlide preclose technique offers a simple, highly effective, and safe method for closure of the arterial access site after transfemoral TAVI. The double-ProGlide strategy results in low rates of major vascular complications and translates into favorable early outcome.

Cyclosporine A impairs norepinephrine-induced vascular contractility.

Usage of cyclosporine A (CsA) after kidney transplantation may be associated with development of nephrotoxicity and vasculopathy, but the mechanisms by which CsA causes vascular dysfunction are still under scrutiny. We established a transplantation model and investigated the effect of CsA on vascular contractility with the aid of a pressurized myograph in comparison with control and unilaterally nephrectomized rats. Results were correlated with mRNA expression studies of α- and ß-adrenoreceptors, in mesenteric resistance arteries versus the thoracic aorta. Consequences of everolimus on functional properties as well as adrenoreceptor expression were also studied. CsA significantly downregulated expression of mesenteric adrenoreceptors, whereas no effect on aortic adrenoreceptors was seen. Administration of everolimus had no influence on mRNA adrenoreceptor expression in mesenteric resistance arteries. Furthermore, contractile responses of mesenteric resistance arteries to norepinephrine were markedly reduced after treatment with CsA, while there was no difference in contraction by endothelin. Everolimus did not alter the contractility response at all. In summary, norepinephrine-induced, but not endothelin-induced, contractile responses of mesenteric resistance arteries are blunted in CsA-treated rats. This finding was accompanied by a marked downregulation of adrenoreceptors in mesenteric resistance arteries and was limited to the usage of CsA.

Eplerenone prevents salt-induced vascular stiffness in Zucker diabetic fatty rats: a preliminary report.

BACKGROUND: Aldosterone levels are elevated in a rat model of type 2 diabetes mellitus, the Zucker Diabetic fatty rat (ZDF). Moreover blood pressure in ZDF rats is salt-sensitive. The aim of this study was to examine the effect of the aldosterone antagonist eplerenone on structural and mechanical properties of resistance arteries of ZDF-rats on normal and high-salt diet. METHODS: After the development of diabetes, ZDF animals were fed either a normal salt diet (0.28%) or a high-salt diet (5.5%) starting at an age of 15 weeks. ZDF rats on high-salt diet were randomly assigned to eplerenone (100 mg/kg per day, in food) (ZDF+S+E), hydralazine (25 mg/kg per day) (ZDF+S+H), or no treatment (ZDF+S). Rats on normal salt-diet were assigned to eplerenone (ZDF+E) or no treatment (ZDF). Normoglycemic Zucker lean rats were also divided into two groups receiving normal (ZL) or high-salt diet (ZL+S) serving as controls. Systolic blood pressure was measured by tail cuff method. The experiment was terminated at an age of 25 weeks. Mesenteric resistance arteries were studied on a pressurized myograph. Specifically, vascular hypertrophy (media-to-lumen ratio) and vascular stiffness (strain and stress) were analyzed. After pressurized fixation histological analysis of collagen and elastin content was performed. RESULTS: Blood pressure was significantly higher in salt-loaded ZDF compared to ZDF. Eplerenone and hydralazine prevented this rise similarily, however, significance niveau was missed. Media-to-lumen ratio of mesenteric resistance arteries was significantly increased in ZDF+S when compared to ZDF and ZL. Both, eplerenone and hydralazine prevented salt-induced vascular hypertrophy. The strain curve of arteries of salt-loaded ZDF rats was significantly lower when compared to ZL and when compared to ZDF+S+E, but was not different compared to ZDF+S+H. Eplerenone, but not hydralazine shifted the strain-stress curve to the right indicating a vascular wall composition with less resistant components. This indicates increased vascular stiffness in salt-loaded ZDF rats, which could be prevented by eplerenone but not by hydralazine. Collagen content was increased in ZL and ZDF rats on high-salt diet. Eplerenone and hydralazine prevented the increase of collagen content. There was no difference in elastin content. CONCLUSION: Eplerenone and hydralazine prevented increased media-to-lumen ratio in salt-loaded ZDF-rats, indicating a regression of vascular hypertrophy, which is likely mediated by the blood pressure lowering-effect. Eplerenone has additionally the potential to prevent increased vascular stiffness in salt-loaded ZDF-rats. This suggests an effect of the specific aldosterone antagonist on adverse vascular wall remodelling.

Hyperaldosteronism and altered expression of an SGK1-dependent sodium transporter in ZDF rats leads to salt dependence of blood pressure.

This study was designed to test whether altered aldosterone-related sodium handling leads to salt-sensitive blood pressure in diabetes and thus may exaggerate end-organ damage. Zucker diabetic fatty (ZDF) rats, a model of type 2 diabetes, and Zucker lean (ZL) rats, as euglycemic controls, were divided into groups receiving normal (0.28%) (ZDF+N, ZL+N) and high-salt (5.5%) diets (ZDF+S, ZL+S) for 10 weeks. Renal mRNA expression of serum- and glucocorticoid-inducible kinase 1 (SGK1) and sodium transporters (for example, the epithelial sodium channel-α, ENaCα) were measured by quantitative reverse transcriptase-PCR. Vascular hypertrophy (media-to-lumen ratio, M/L) in mesenteric resistance arteries was assessed using a pressurized myograph. Systolic blood pressure (SBP) was significantly higher in ZDF+S vs. ZDF+N (146 ± 2 vs. 133 ± 3 mm Hg; P<0.05), whereas there was no difference between ZL+S and ZL+N (151 ± 3 vs. 147 ± 3 mm Hg). Plasma sodium concentration was higher in ZDF+S vs. ZDF+N, whereas there was no difference between ZL+S and ZL+N. Plasma aldosterone concentration (PAC) was higher in ZDF+N as compared with ZL+N (191 ± 23 vs. 95 ± 35 pg ml(-1); P<0.05). PAC decreased to zero in ZL+S, which was not the case in ZDF+S (0 ± 0 vs. 37 ± 2 pg ml(-1)). Salt loading decreased the mRNA expression of SGK1 in euglycemic controls (ZL+S 0.58 ± 0.2 vs. ZL+N 1.05 ± 0.05; P=0.05), whereas it significantly increased SGK1 expression in diabetic rats (ZDF+S 1.75 ± 0.15 vs. ZDF+N 0.92 ± 0.07; P<0.01). ENaCα mRNA expression paralleled these changes. The M/L of mesenteric resistance arteries was not different between ZDF+N and ZL+N. High salt significantly increased the M/L in ZDF+S vs. ZDF+N, but not in ZL+S vs. ZL+N. Systolic blood pressure in this model of type 2 diabetes mellitus is salt sensitive, leading to marked vascular remodeling. The underlying pathophysiological mechanism may be inappropriately high levels of aldosterone and up-regulation of SGK1-dependent renal sodium transport by ENaCα, leading to net increased sodium retention.

Endothelial cell seeding fails to prevent intimal hyperplasia following arterial injury in the rat carotid model.

PURPOSE: Aim of the study was to evaluate the therapeutic potential of endothelial cell seeding to inhibit the neointimal response after balloon injury of the rat carotid artery. METHODS AND RESULTS: Endothelial cells were isolated from peripheral blood after cytokine-stimulation (PB-EC), the bone marrow compartment (BM-EC), and the thoracic aorta (AO-EC) of male rats. The EC-populations were characterized by microscopy, cytofluorometry, and PCR-analysis, and displayed distinct patterns of RNA-expression of the EC-markers VEGF-receptor 1 and 2, and TIE2. 5 x 10(5) ECs were incubated in the freshly balloon-denuded arterial bed for 30 min achieving about 70% coverage with all 3 EC-populations. However, the neointimal response 2 weeks after the procedure was significantly aggravated in the EC-seeded carotids (I/M-ratio: non-seeded Control 1.00 +/- 0.10, PB-EC 1.53 +/- 0.07, BM-EC 1.64 +/- 0.12, and AO-EC 1.55 +/- 0.14; P < 0.05 vs. Control for all). We found evidence for an accelerated cell-turnover (TUNEL-assay, total cell-density, infiltration with CD45(pos) haematopoietic cells) especially in the adventitia of the treated vessels. CONCLUSION: Endothelial cell seeding fails to prevent intimal hyperplasia following arterial injury in the rat carotid model.

A systemic combination therapy with granulocyte-colony stimulating factor plus erythropoietin aggravates the healing process of balloon-injured rat carotid arteries.

OBJECTIVE: Percutaneous vascular interventions lead inevitably to a destruction of the endothelial lining at the site of injury. There are conflicting data on the therapeutic benefit of hematopoietic growth factors aiming at mobilisation of circulating endothelial cells to accelerate the reendothelialisation process. Aim of our study was to evaluate the impact of a maximised 7 day-combination therapy with G-CSF plus EPO on the healing process following balloon injury of the rat carotid artery. METHODS AND RESULTS: Osmotic pumps to systemically deliver G-CSF and EPO at saturating doses during the first seven days post injury were implanted into the peritoneal cavity of splenectomised male Sprague-Dawley rats. Cytokine treatment resulted in significantly elevated numbers of white blood cells, hematocrit levels, circulating hematopoietic stem cells, and-temporarily-circulating endothelial precursors. Functional reendothelialisation as assessed by Evan's blue staining on day 14 post injury was not affected by the cytokine treatment. The neointimal response was analysed on day 7 and 28 post injury, and was significantly higher at the day 7 timepoint (Cytokines: I/M-ratio 1.10+/-0.09 vs. Saline: 0.36+/-0.06). Cytokine treated rats also displayed higher rates of thrombotic occlusion (Cytokines: 25-33% vs. Saline: 0%). Serum levels of PAI-1, TGFbeta1, and PDGF-BB were not elevated in the cytokine treated rats. The proliferative rates both in the injured vessel wall and the surrounding adventitia as assessed by BrdU incorporation were significantly higher in the cytokine treated animals. The number of CD45(pos) hematopoietic cells was significantly higher in the adventitia of the cytokine treated rats. Vasa vasorum were not found to be significantly different. The increased neointimal response was not due to expression of G-CSF- or EPO-receptors on VSMCs within the vessel wall or myofibroblasts in the adventitia. CONCLUSION: The systemic administration of G-CSF plus EPO during the first week after balloon-injury impairs the vascular healing process by increasing the neointimal response and the risk for thrombotic occlusion.

General aneurysmatosis due to cheese consumption: complications of an endocarditis caused by Lactococcus cremoris.

We describe a case of endocarditis due to Lactococcus cremoris associated with cheese consumption, that caused multiple mycotic aneurysms. Antibiotic treatment combined with surgical and radiological interventions resulted in full recovery.

Evidence for a possible inhibitory interaction between the HO-1/CO- and Akt/NO-pathways in human endothelial cells.

OBJECTIVE: The protective properties of heme oxygenase 1 (HO-1) give reason to study this mechanism as a potential therapeutic target for inflammatory and cardiovascular diseases. Recent evidence suggests a possible interaction between the HO-1/CO- and the protein kinase Akt/NO-pathway. This study was designed to examine the effects of continuous HO-1 overexpression in endothelial cells. METHODS: Oncoretroviral vectors were constructed to achieve constitutive overexpression of HO-1, Akt, and green fluorescence protein in human umbilical vein endothelial cells. [(3)H]thymidine-incorporation and lipid-peroxidation were measured following exposure to heme and H(2)O(2). Expression of HO-1, Akt and its downstream-target endothelial NO-synthase were quantified by Western blot analysis. NO-synthase-activity was measured using the citrulline-conversion-assay. RESULTS: HO-1-overexpression reduced proliferative rates and DNA-synthesis of HUVEC, but provided potent protection from oxidative stress induced by heme and H(2)O(2). Phosphorylated-Akt and eNOS was downregulated in HO-1-HUVEC. eNOS-activity was reduced in HO-1-HUVEC. Co-infection with the Akt-retrovirus restored proliferative rates and eNOS-expression and -activity. CONCLUSION: Continuously elevated HO-1-activity protects EC from oxidative stress but inhibits Akt-mediated proliferation and eNOS-expression. This inhibitory feedback mechanism could be a limitation of HO-1 as a target for the treatment of vascular disease.

Myocardial hypertrophy and enhanced left ventricular contractility in Zucker diabetic fatty rats.

Heart failure is known to be a complication of insulin-dependent (IDDM) and noninsulin-dependent diabetes mellitus (NIDDM) even in the absence of coronary heart disease or hypertension. The mechanisms leading to diabetic cardiomyopathy are unknown. The aim of the study was to characterize structural and functional alterations in hyperinsulinemic Zucker diabetic fatty (ZDF) rats treated with or without insulin. Diabetic animals showed a twofold increase in cardiomyocyte volume with increased left ventricular ANP but not BNP mRNA levels in spite of a reduced plasma renin activity (PRA) 2 months after onset of diabetes compared to nondiabetic littermates. These changes were associated with an increase in left ventricular performance as assessed by echocardiography. Insulin treatment led to a significant increase in body weight (BW), total heart weight, myocardial protein content, and left ventricular mass (LVM). Perivascular fibrosis and laminin thickness were significantly augmented in diabetic rat myocardium irrespective of insulin treatment, whereas interstitial collagen I and fibronectin were similarly found in diabetic and control myocardium. Initial stages of diabetic cardiomyopathy in hyperinsulinemic rats are characterized by cardiomyocyte hypertrophy and enhanced cardiac contractility. It is suggested that hyperinsulinemia may be involved in cardiac hypertrophy.

Isolation and transplantation of autologous circulating endothelial cells into denuded vessels and prosthetic grafts: implications for cell-based vascular therapy.

BACKGROUND: Blood-borne endothelial cells originating from adult bone marrow were reported previously. These cells have the properties of an endothelial progenitor cell (EPC) and can be mobilized by cytokines and recruited to sites of neovascularization, where they differentiate into mature endothelial cells. Current protocols for isolation of EPCs from peripheral blood rely on enrichment and selection of CD34+ mononuclear cells. METHODS AND RESULTS: In this report, we describe a streamlined method for the isolation and expansion of EPCs from peripheral blood and evaluate their therapeutic potential for autologous cell-based therapy of injured blood vessels and prosthetic grafts. A subset of unfractionated mononuclear cells exhibited the potential to differentiate in vitro into endothelial cells under selective growth conditions. The cells were efficiently transduced ex vivo by a retroviral vector expressing the LacZ reporter gene and could be expanded to yield sufficient numbers for therapeutic applications. Transplantation of these cells into balloon-injured carotid arteries and into bioprosthetic grafts in rabbits led to rapid endothelialization of the denuded vessels and graft segments, resulting in significant reduction in neointima deposition. CONCLUSIONS: We conclude that transplantation of EPCs may play a crucial role in reestablishing endothelial integrity in injured vessels, thereby inhibiting neointimal hyperplasia. These findings may have implications for novel and practical cell-based therapies for vascular disease.

Vascular gene delivery of anticoagulants by transplantation of retrovirally-transduced endothelial progenitor cells.

OBJECTIVE: Recent studies have documented the presence of bone marrow-derived endothelial progenitor cells (EPC) in the circulation of several species. This study was designed to evaluate the use of engineered EPC for vascular gene delivery into angioplasty-induced arterial lesions. METHODS AND RESULTS: EPC could easily be isolated from whole bone marrow and peripheral blood of adult rats. Differentiation was induced by culture on fibronectin in the presence of endothelial specific growth factors. Rat EPC shared several phenotypic and functional properties with mature endothelial cells. Recombinant retroviruses were generated encoding for the anticoagulants tissue-type plasminogen activator (tPA) and hirudin. Efficient (>90%) ex vivo gene transfer could be achieved resulting in high levels of transgene production. Engineered EPC were locally infused into freshly balloon-injured carotid arteries. Analysis of day 7 vessels showed 73+/-10% luminal coverage of the lesioned arterial bed with transduced EPC. Sustained secretion of both anticoagulants could be detected in organ cultures of explanted arteries. EPC seeding inhibited dilation of the injured arterial segment and prevented reduction of media thickness. However, rapid repopulation with EPC failed to attenuate neointima formation in this model. CONCLUSIONS: Peripheral blood and bone marrow can be used as source for endothelial lineage cells. Cultured EPC can be genetically engineered by retroviral gene transfer and serve as cellular vehicles for vascular gene and drug delivery of anticoagulants. Local transplantation of EPC attenuates reendothelialization of angioplasty-injured arteries but fails to inhibit neointima proliferation.

Norepinephrine upregulates vascular endothelial growth factor in rat cardiac myocytes by a paracrine mechanism.

Norepinephrine has growth-promoting effects in cardiac myocytes. The present study in cultured neonatal rat cardiac myocytes tested the hypothesis that norepinephrine also stimulates expression of vascular endothelial growth factor (VEGF), an important angiogenic factor. As assessed by polymerase chain reaction cardiac myocytes and non-myocytes expressed all three isoforms of rat VEGF, with the short isoform (VEGF 121 ) preferentially expressed in non-myocytes. When cardiac myocytes were stimulated with 1 micro M norepinephrine for 24 h in the presence or absence of the specific alpha - and beta -adrenoceptor antagonists prazosin and propranolol, respectively, VEGF mRNA levels and splice variant pattern did not change, whereas atrial natriuretic peptide mRNA levels increased 3 to 4-fold. CoCl(2) increased VEGF mRNA levels in cardiac myocytes five-fold. When cardiac myocytes were cultured with conditioned medium from non-myocytes that had been stimulated with norepinephrine for 24 h VEGF mRNA increased 2-fold. The increase was blocked by antibodies neutralizing TGF beta. These data suggest that norepinephrine stimulates myocardial angiogenesis by a paracrine mechanism that involves cardiac non-myocytes and TGF beta.