Refine
Year of publication
Has Fulltext
- yes (63)
Is part of the Bibliography
- no (63)
Keywords
- TAVI (4)
- alirocumab (4)
- Aortic stenosis (3)
- Inflammation (3)
- acute coronary syndrome (3)
- Cardiovascular biology (2)
- MitraClip (2)
- biomarker (2)
- 16 segment AHA model (1)
- Acute coronary syndrome (1)
Institute
Aims: Stroke is a major complication after transcatheter aortic valve implantation (TAVI). Although multifactorial, it remains unknown whether the valve deployment system itself has an impact on the incidence of early stroke. We performed a meta- and network analysis to investigate the 30-day stroke incidence of self-expandable (SEV) and balloon-expandable (BEV) valves after transfemoral TAVI.
Methods and results: Overall, 2723 articles were searched directly comparing the performance of SEV and BEV after transfemoral TAVI, from which 9 were included (3086 patients). Random effects models were used for meta- and network meta-analysis based on a frequentist framework. Thirty-day incidence of stroke was 1.8% in SEV and 3.1% in BEV (risk ratio of 0.62, 95% confidence interval (CI) 0.49–0.80, p = 0.004). Treatment ranking based on network analysis (P-score) revealed CoreValve with the best performance for 30-day stroke incidence (75.2%), whereas SAPIEN had the worst (19.0%). However, network analysis showed no inferiority of SAPIEN compared with CoreValve (odds ratio 2.24, 95% CI 0.70–7.2).
Conclusion: Our analysis indicates higher 30-day stroke incidence after transfemoral TAVI with BEV compared to SEV. We could not find evidence for superiority of a specific valve system. More randomized controlled trials with head-to-head comparison of SEV and BEV are needed to address this open question.
Bone vasculature provides protection and signals necessary to control stem cell quiescence and renewal1. Specifically, type H capillaries, which highly express Endomucin, constitute the endothelial niche supporting a microenvironment of osteoprogenitors and long-term hematopoietic stem cells2–4. The age-dependent decline in type H endothelial cells was shown to be associated with bone dysregulation and accumulation of hematopoietic stem cells, which display cell-intrinsic alterations and reduced functionality3. The regulation of bone vasculature by chronic diseases, such as heart failure is unknown. Here, we describe the effects of myocardial infarction and post-infarction heart failure on the vascular bone cell composition. We demonstrate an age-independent loss of type H bone endothelium in heart failure after myocardial infarction in both mice and in humans. Using single-cell RNA sequencing, we delineate the transcriptional heterogeneity of human bone marrow endothelium showing increased expression of inflammatory genes, including IL1B and MYC, in ischemic heart failure. Inhibition of NLRP3-dependent IL-1β production partially prevents the post-myocardial infarction loss of type H vasculature in mice. These results provide a rationale for using anti-inflammatory therapies to prevent or reverse the deterioration of vascular bone function in ischemic heart disease.
Cathepsin D (CatD) is a lysosomal aspartic proteinase and plays an important role in the degradation of proteins and in apoptotic processes induced by oxidative stress, cytokines, and aging. All of these stimuli are potent inducers of endothelial cell apoptosis. Therefore, we investigated the role of CatD in endothelial cell apoptosis and determined the underlying mechanisms. Incubation with 100-500 microm H2O2 for 12 h induced apoptosis in endothelial cells. To determine a role for CatD, we co-incubated endothelial cells with the CatD inhibitor pepstatin A. Pepstatin A as well as genetic knock down of CatD abolished H2O2-induced apoptosis. In contrast, overexpression of CatD wild type but not a catalytically inactive mutant of CatD (CatDD295N) induced apoptosis under basal conditions. To gain insights into the underlying mechanisms, we investigated the effect of CatD on reactive oxygen species (ROS) formation. Indeed, knocking down CatD expression reduced H2O2-induced ROS formation and apoptosis. The major redox regulator in endothelial cells is thioredoxin-1 (Trx), which plays a crucial role in apoptosis inhibition. Thus, we hypothesized that CatD may alter Trx protein levels and thereby promote formation of ROS and apoptosis. Incubation with 100 microm H2O2 for 6 h decreased Trx protein levels, whereas Trx mRNA was not altered. H2O2-induced Trx degradation was inhibited by pepstatin A and genetic knock down of CatD but not by other protease inhibitors. Incubation of unstimulated cell lysates with recombinant CatD significantly reduced Trx protein levels in vitro, which was completely blocked by pepstatin A pre-incubation. Overexpression of CatD reduced Trx protein in cells. Moreover, H2O2 incubation led to a translocation of Trx to the lysosomes prior to the induction of apoptosis. Taken together, CatD induces apoptosis via degradation of Trx protein, which is an essential anti-apoptotic and reactive oxygen species scavenging protein in endothelial cells.