10 research outputs found
Transaortic transcatheter aortic valve implantation: Results of the Polish arm of the ROUTE registry
Background: Transaortic (TAo) transcatheter aortic valve implantation (TAVI) is an alterÂnative approach in patients considered to be at high risk for classical open surgery with poor peripheral vessel access. The purpose of this study was to determine the feasibility of using TAo access for TAVI procedures employing the Edwards SAPIEN transcatheter heart valve. The primary objective was to determine overall 30-day mortality.
Methods: A total of 32 patients with severe aortic valve stenosis underwent TAo-TAVI using Edwards SAPIEN bioprostheses. Postoperative results were collected according to the Registry of the Utilization Of the TAo-TAVI approach using the Edwards SAPIEN Valve (ROUTE) study protocol. Complications were assessed using Valve Academic Research Consortium- 2 (VARC-2) criteria.
Results: The mean age of the population was 80.9 ± 5.2 years, with 53.1% being female. All patients received either the SAPIEN XT or the SAPIEN 3 bioprosthesis (Edwards Lifesciences). Device success was achieved in 100% of cases. One (3.25%) patient subsequently suffered an aortic dissection and required ascending aorta replacement. Paravalvular leakage was absent or mild in 26 (81%) patients, and moderate in 6 (19%) patients. Other complications included permanent pacemaker implantation in 2 (6.5%), and transient post operative delirium in 2 (6.5%) patients. The total hospital stay was 6.7 ± 2.4 days. New York Heart Association class decreased significantly on follow-up. Thirty-day mortality rate was 2 (6.5%) patients.
Conclusions: Use of TAo access for TAVI procedures has a reasonable clinical outcome and is a safe alternative to the transfemoral and transapical approaches, especially for patients with high-risk peripheral vessel access
Toll-like receptor 3 signalling mediates angiogenic response upon shock wave treatment of ischaemic muscle
Aims Shock wave therapy (SWT) represents a clinically widely used angiogenic and thus regenerative approach for the treatment of ischaemic heart or limb disease. Despite promising results in preclinical and clinical trials, the exact mechanism of action remains unknown. Toll-like receptor 3, which is part of the innate immunity, is activated by binding doublestranded (ds) RNA. It plays a key role in inflammation, a process that is needed also for angiogenesis. We hypothesize that SWT causes cellular cavitation without damaging the target cells, thus liberating cytoplasmic RNA that in turn activates TLR3. Methods and results SWT induces TLR3 and IFN-b1 gene expression as well as RNA liberation from endothelial cells in a time-dependant manner. Conditioned medium from SWT-treated HUVECs induced TLR3 signalling in reporter cells. The response was lost when the medium was treated with RNase III to abolish dsRNAs or when TLR3 was silenced using siRNAs. In a mouse hind limb ischaemia model using wt and TLR3 2/2 mice (n Œ 6), SWT induced angiogenesis and arteriogenesis only in wt animals. These effects were accompanied by improved blood perfusion of treated limbs. Analysis of main molecules of the TLR3 pathways confirmed TLR3 signalling in vivo following SWT. Conclusion Our data reveal a central role of the innate immune system, namely Toll-like receptor 3, to mediate angiogenesis upon release of cytoplasmic RNAs by mechanotransduction of SWT. -
Low energy shock wave therapy induces angiogenesis in acute hind-limb ischemia via VEGF receptor 2 phosphorylation
Objectives: Low energy shock waves have been shown to induce angiogenesis, improve left ventricular ejection fraction and decrease angina symptoms in patients suffering from chronic ischemic heart disease. Whether there is as well an effect in acute ischemia was not yet investigated.
Methods: Hind-limb ischemia was induced in 10â12 weeks old male C57/Bl6 wild-type mice by excision of the left femoral artery. Animals were randomly divided in a treatment group (SWT, 300 shock waves at 0.1 mJ/mm2, 5 Hz) and untreated controls (CTR), n = 10 per group. The treatment group received shock wave therapy immediately after surgery.
Results: Higher gene expression and protein levels of angiogenic factors VEGF-A and PlGF, as well as their receptors Flt-1 and KDR have been found. This resulted in significantly more vessels per high-power field in SWT compared to controls. Improvement of blood perfusion in treatment animals was confirmed by laser Doppler perfusion imaging. Receptor tyrosine kinase profiler revealed significant phosphorylation of VEGF receptor 2 as an underlying mechanism of action. The effect of VEGF signaling was abolished upon incubation with a VEGFR2 inhibitor indicating that the effect is indeed VEGFR 2 dependent.
Conclusions: Low energy shock wave treatment induces angiogenesis in acute ischemia via VEGF receptor 2 stimulation and shows the same promising effects as known from chronic myocardial ischemia. It may therefore develop as an adjunct to the treatment armentarium of acute muscle ischemia in limbs and myocardium
Shock wave treatment induces angiogenesis and mobilizes endogenous CD31/CD34-positive endothelial cells in a hindlimb ischemia model: Implications for angiogenesis and vasculogenesis
ObjectivesShock waves have been shown to induce recruitment of intravenously injected endothelial progenitor cells to ischemic hind limbs in rats. We hypothesized that shock wave treatment as sole therapy would induce angiogenesis in this ischemia model and would lead to mobilization of endogenous endothelial (progenitor) cells.MethodsA total of 18 rats, aged 5 weeks old, were subdivided into 3 groups: sham (n = 6), ischemic muscle with shock wave treatment (shock wave treatment group, n = 6), and without shock wave treatment (control, n = 6). Hind limb ischemia was induced by ligation of the femoral artery. Three weeks later, shock wave treatment (300 impulses at 0.1 mJ/mm2) was applied to the adductor muscle; the controls were left untreated. Muscle samples were analyzed using real-time polymerase chain reaction for angiogenic factors and chemoattractants for endothelial progenitor cell mobilization. Fluorescence activated cell sorting analysis of the peripheral blood was performed for CD31/CD34-positive cells. Perfusion was measured using laser Doppler imaging. Functional improvement was evaluated by walking analysis.ResultsAngiogenic factors/endothelial progenitor cell chemoattractants, stromal cell-derived factor-1 and vascular endothelial growth factor, were increased in the treatment group, as shown by real-time polymerase chain reaction, indicating the mobilization of endothelial progenitor cells. Fluorescence activated cell sorting analysis of the peripheral blood revealed high numbers of CD31/CD34-positive cells in the treatment group. Greater numbers of capillaries were found in the treated muscles. Blood perfusion increased markedly in the treatment group and led to functional restoration, as shown by the results from the walking analysis.ConclusionsShock wave therapy therefore could develop into a feasible alternative to stem cell therapy in regenerative medicine, in particular for ischemic heart and limb disease
VEGF-A protein expression and stimulation of VEGF receptor 2.
<p>A, Pivotal growth factor VEGF-A protein was measured 4 weeks after left femoral artery excision and shock wave treatment by western blot analysis of muscle samples. VEGF-A protein was significantly increased in the treatment group (SWT) compared to untreated controls (CTR). *p<.05. B, Profiler assays were used to investigate the role of receptor tyrosine kinase after shock wave treatment. Results indicate that shock waves stimulate phosphorylation of VEGF receptor 2 whereas there was no effect observed on VEGFR1 phosphorylation. Increase in VEGFR2 phosphorylation is nearly five-fold compared to untreated controls. C, Western blot of HUVECs under hypoxic conditions showing clearly higher protein levels of VEGF-A after shock wave treatment. D, Western blot of phoshpo-p44/42 MAPK (ERK1/2) shows that VEGF signaling is abolished in shock wave treated HUVECs that were pre-incubated with VEGF receptor 2 inhibitor Vandetanib. This finding indicates that shock wave effects are VEGFR2-dependent. E, Relative protein levels of VEGF 24 hours after shock wave treatment of human umbilical vein endothelial cells (HUVECs) as assessed by angiogenesis profiler. F, Relative protein levels of PlGF 24 hours after treatment of HUVECs.</p
Increase of angiogenic factors in shock wave treated ischemic muscle.
<p>Significantly elevated mRNA levels of angiogenic growth factors A, VEGF-A and B, PlGF 72 hours after shock wave treatment (SWT). In line with these findings their main receptors C, Flt-1 and D, KDR were significantly upregulated in the treatment group compared to untreated controls (CTR). *p<.05.</p
Higher numbers of capillary sprouts from aortic rings in the treatment group.
<p>A, Representative pictures from light microscope of untreated (CTR) and shock wave treated (SWT) mouse aortic rings depicting higher numbers of sprouts in the treatment group 7 days following SWT. B, Quantification of sprouts revealed a significant increase in the treatment group, *p<.05, nâ=â6â8 per group. C, Immunofluorescence confirmed that sprouts consist of endothelial cells (red: lectin endothelial staining, blue: DAPI nucleus counterstaining).</p
Increase of capillary and arteriole density in ischemic muscle.
<p>A, Representative views of immunofluorescence stainings for DAPI (cell nuclei) and CD31 (endothelial cells). Magnification x400; B, Increase of capillary density in treated ischemic muscle. Immunofluorescence staining for CD31-positive cells revealed significantly higher numbers of capillaries per high power field (HPF) 4 weeks after shock wave therapy (SWT). *p<.05. C, Representative views of immunofluorescence stainings for arterioles (CD31â endothelial cells, alpha-SMA â smooth muscle cells). Magnification x200; D, Quantification of arteriole staining revealed significantly more arterioles per HPF in shock wave treated muscle. *p<.05.</p