Comparison of dual antiplatelet therapy versus oral anticoagulation following transcatheter aortic valve replacement: A retrospective single-center registry analysis

Background: The choice of optimal antithrombotic regimen after transcatheter aortic valve replace-ment (TAVR) remains a matter of debate. The objective of this study was to compare both efficacy and safety outcomes based on the type of antithrombotic therapy prescribed after TAVR Methods: This is a retrospective analysis of 514 consecutive patients treated with either dual antiplate¬let therapy (DAPT) (n = 315; 61.3%) or oral anticoagulation (OAC) plus clopidogrel (n = 199; 38.7%) for a minimum of 3 months after TAVR followed by antiplatelet monotherapy or OAC only, respectively. Patients had pre-defined clinical and echocardiographic follow-ups at 30 days, 6 and 12 months. The key efficacy endpoint was a composite of all-cause death, myocardial infarction, stroke and valve throm¬bosis at 1 year. The key safety endpoint was the occurrence of life-threatening/major bleeding at 1 year. Results: Baseline characteristics did not differ between both groups, except for a higher incidence of atrial fibrillation in the OAC group. No significant differences in both efficacy and safety endpoints were observed at 30 days and 6 months. At 1 year, the key efficacy endpoint occurred in 21.5% of the DAPT group compared to 19.7% of the OAC group (p = 0.61). The key safety endpoint occurred in 25.1% and 27.8%, respectively (p = 0.53). However, after 1 year valve thrombosis was reported in 8 (2.5%) patients in the DAPT group but not in the OAC group (p = 0.02). Conclusions: OAC after TAVR seems to reduce the risk of clinical valve thrombosis without a statisti-cally significant increase in bleeding complications

Vasoactive intestinal polypeptide mediates circadian rhythms in Mammalian olfactory bulb and olfaction

Accumulating evidence suggests that the olfactory bulbs (OBs) function as an independent circadian system regulating daily rhythms in olfactory performance. However, the cells and signals in the olfactory system that generate and coordinate these circadian rhythms are unknown. Using real-time imaging of gene expression, we found that the isolated olfactory epithelium and OB, but not the piriform cortex, express similar, sustained circadian rhythms in PERIOD2 (PER2). In vivo, PER2 expression in the OB of mice is circadian, approximately doubling with a peak around subjective dusk. Furthermore, mice exhibit circadian rhythms in odor detection performance with a peak at approximately subjective dusk. We also found that circadian rhythms in gene expression and odor detection performance require vasoactive intestinal polypeptide (VIP) or its receptor VPAC2R. VIP is expressed, in a circadian manner, in interneurons in the external plexiform and periglomerular layers, whereas VPAC2R is expressed in mitral and external tufted cells in the OB. Together, these results indicate that VIP signaling modulates the output from the OB to maintain circadian rhythms in the mammalian olfactory system.Fil: Kang Miller, Jae Eun. Washington University in St. Louis; Estados UnidosFil: Granados Fuentes, Daniel. Washington University in St. Louis; Estados UnidosFil: Wang, Thomas. Washington University in St. Louis; Estados UnidosFil: Marpegan, Luciano. Washington University in St. Louis; Estados Unidos. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Holy, Timothy E.. Washington University in St. Louis; Estados UnidosFil: Herzog, Erik D.. Washington University in St. Louis; Estados Unido

Guggulsterone, an anti-inflammatory phytosterol, inhibits tissue factor and arterial thrombosis

Background: The phytosterol guggulsterone is a potent anti-inflammatory mediator with less side effects than classic steroids. This study assesses the impact of guggulsterone on tissue factor (TF) expression and thrombus formation. Methods and results: Guggulsterone inhibited TNF-α-induced endothelial TF protein expression and surface activity in a concentration-dependent manner; in contrast, dexamethasone did not affect TNF-α-induced TF expression. Guggulsterone enhanced endothelial tissue factor pathway inhibitor and impaired plasminogen activator inhibitor-1 as well as vascular cell adhesion molecule-1 protein. Real-time polymerase chain reaction revealed that guggulsterone inhibited TNF-α-induced TF mRNA expression; moreover, it impaired activation of the MAP kinases JNK and p38, while that of ERK remained unaffected. In vivo, guggulsterone inhibited TF activity and photochemical injury induced thrombotic occlusion of mouse carotid artery. Guggulsterone also inhibited TF expression, proliferation, and migration of vascular smooth muscle cells in a concentration-dependent manner. Conclusions: Guggulsterone inhibits TF expression in vascular cells as well as thrombus formation in vivo; moreover, it impairs vascular smooth muscle cell activation. Hence, this phytosterol offers novel therapeutic options, in particular in inflammatory diseases associated with an increased risk of thrombosi

Clinical outcomes of a balloon-expandable stent for symptomatic obstructions of the subclavian or innominate arteries

Background: Upper-extremity peripheral arterial disease (PAD) may present with a broad spectrum of signs and symptoms. If an endovascular treatment is planned, percutaneous angioplasty and stent placement may lead to a better patency compared to percutaneous angioplasty alone. We assessed the characteristics and clinical course of patients with upper-extremity PAD who received angioplasty and a balloon-expandable stent. Patients and methods: We analyzed data from consecutive patients treated with angioplasty and placement of a balloon-expandable BeSmooth Peripheral Stent System$^{®}$ (Bentley, Germany) at the Angiology Department (University Hospital Zurich) between 2018 and 2022. The primary outcome was re-intervention at the target lesion within 6 months from index angioplasty and during available follow-up. The study was approved by the local ethical commission. Results: A total of 27 patients were treated. The median age was 70 (Q1-Q3: 60-74) years and 59% were men. The subclavian artery (74%) represented the most frequently treated target lesion, followed by the innominate artery (26%). The mean improvement in blood pressure in the treated arm was 21 (95%CI 7 to 35) mmHg at 24 hours and 29 (95%CI 15 to 43) mmHg at 6 months. At 6 months, 2 (8%) patients required a target lesion re-intervention. During the remaining follow-up period up to 24 months, one of these two patients required additional intervention and a total of 3 (11%) patients died due to sepsis, cancer, and unknown causes, respectively. Conclusions: Percutaneous catheter-based treatment with a balloon-expandable stent for symptomatic upper extremity PAD appeared to be effective and safe

Clinical outcomes of ultrasound-assisted coagulation monitoring-adjusted catheter-directed thrombolysis for acute pulmonary embolism

BACKGROUND Ultrasound-assisted catheter-directed thrombolysis (USAT) may reverse right ventricular dysfunction due to acute pulmonary embolism (PE) with a favorable safety profile. METHODS We studied intermediate-high- and high-risk acute PE patients who underwent USAT at the University Hospital Zurich, 2018-2022. The USAT regimen included alteplase 10 mg per catheter over 15 h, therapeutic-dosed heparin, and dosage adaptations based on routinely monitored coagulation parameters, notably anti-factor Xa activity and fibrinogen. We focused on the mean pulmonary arterial pressure (mPAP) and the National Early Warning Score (NEWS) before and after USAT, and reported the incidence of hemodynamic decompensation, PE recurrence, major bleeding, and death over 30 days. RESULTS We included 161 patients: 96 (59.6 %) were men and the mean age was 67.8 (SD 14.6) years. Mean PAP decreased from a mean of 35.6 (SD 9.8) to 25.6 (SD 8.2) mmHg, whereas the NEWS decreased from a median of 5 (Q1-Q3 4-6) to 3 (Q1-Q3 2-4) points. No cases of hemodynamic decompensation occurred. One (0.6 %) patient had an episode of recurrent PE. Two (1.2 %) major bleeding events occurred, including one (0.6 %) intracranial, fatal hemorrhage in a patient with high-risk PE, severe heparin overdosing, and a recent head trauma (with negative CT scan of the brain performed at baseline). No other deaths occurred. CONCLUSIONS USAT resulted in a rapid improvement of hemodynamic parameters among patients with intermediate-high risk acute PE and selected ones with high-risk acute PE, without any recorded deaths related to PE itself. A strategy including USAT, therapeutic-dosed heparin, and routinely monitored coagulation parameters may partly explain the overall very low rate of major bleeding

Antibody-mediated PCSK9 neutralization worsens outcome after bare-metal stent implantation in mice

AIMS Despite advances in pharmacotherapy and device innovation, in-stent restenosis (ISR) and stent thrombosis (ST) remain serious complications following percutaneous coronary intervention (PCI) procedure with stent implantation. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an enzyme involved in plasma cholesterol homeostasis and recently emerged as a therapeutic target for hypercholesterolemia. Antibody-based PCSK9 inhibition is increasingly used in different subsets of patients, including those undergoing PCI. However, whether PCSK9 inhibition affects outcome after stent implantation remains unknown. METHODS AND RESULTS 12 to 14 weeks old C57Bl/6 mice underwent carotid artery bare-metal stent implantation. Compared to sham intervention, stent implantation was associated with increased expression of several inflammatory mediators, including PCSK9. The increase in PCSK9 protein expression was confirmed in the stented vascular tissue, but not in plasma. To inhibit PCSK9, alirocumab was administered weekly to mice before stent implantation. After 6 weeks, histological examination revealed increased intimal hyperplasia in the stented segment of alirocumab-treated animals compared to controls. In vitro, alirocumab promoted migration and inhibited the onset of senescence in primary human vascular smooth muscle cells (VSMC). Conversely, it blunted the migration and increased the senescence of endothelial cells (EC). CONCLUSION Antibody-based PCSK9 inhibition promotes in-stent intimal hyperplasia and blunts vascular healing by increasing VSMC migration, while reducing that of EC. This effect is likely mediated, at least in part, by a differential effect on VSMC and EC senescence. The herein-reported data warrant additional investigations concerning the use of PCSK9 inhibitors in patients undergoing PCI with stent implantation

PI3K/p110α inhibition selectively interferes with arterial thrombosis and neointima formation, but not re-endothelialization: potential implications for drug-eluting stent design

Background Impaired re-endothelialization and stent thrombosis are a safety concern associated with drug-eluting stents (DES). PI3K/p110α controls cellular wound healing pathways, thereby representing an emerging drug target to modulate vascular homoeostasis after injury. Methods and results PI3K/p110α was inhibited by treatment with the small molecule inhibitor PIK75 or a specific siRNA. Arterial thrombosis, neointima formation, and re-endothelialization were studied in a murine carotid artery injury model. Proliferation and migration of human vascular smooth muscle cell (VSMC) and endothelial cell (EC) were assessed by cell number and Boyden chamber, respectively. Endothelial senescence was evaluated by the β-galactosidase assay, endothelial dysfunction by organ chambers for isometric tension. Arterial thrombus formation was delayed in mice treated with PIK75 when compared with controls. PIK75 impaired arterial expression and activity of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1); in contrast, plasma clotting and platelet aggregation did not differ. In VSMC and EC, PIK75 inhibited expression and activity of TF and PAI-1. These effects occurred at the transcriptional level via the RhoA signalling cascade and the transcription factor NFkB. Furthermore, inhibition of PI3K/p110α with PIK75 or a specific siRNA selectively impaired proliferation and migration of VSMC while sparing EC completely. Treatment with PIK75 did not induce endothelial senescence nor inhibit endothelium-dependent relaxations. In line with this observation, treatment with PIK75 selectively inhibited neointima formation without affecting re-endothelialization following vascular injury. Conclusion Following vascular injury, PI3K/p110α inhibition selectively interferes with arterial thrombosis and neointima formation, but not re-endothelialization. Hence, PI3K/p110α represents an attractive new target in DES desig

Major adverse limb events in patients with femoro-popliteal and below-the-knee peripheral arterial disease treated with either sirolimus-coated balloon or standard uncoated balloon angioplasty: a structured protocol summary of the "SirPAD" randomized controlled trial

BACKGROUND: Peripheral arterial disease is a progressive atherosclerotic disease with symptoms ranging from an intermittent claudication to acute critical limb ischemia and amputations. Drug-coated balloons and stents were developed to prevent neo-intimal proliferation and restenosis after percutaneous transluminal angioplasty. Randomized controlled trials showed that drug-coated, notably paclitaxel-coated, devices reduce restenosis, late lumen loss, and the need for target lesion re-vascularization compared with uncoated ones. However, the size of these trials was too small to prove superiority for "hard" clinical outcomes. Moreover, available studies were characterized by too restrictive eligibility criteria. Finally, it remains unclear whether paclitaxel-coated balloons may impair long-term survival. Alternative drug-coated balloons, the so-called limus-based analogs, have been approved for clinical use in patients with peripheral arterial disease. By encapsulating sirolimus in phospholipid drug nanocarriers, they optimize adhesion properties of sirolimus and provide better bioavailability. METHODS: In this investigator-initiated all-comer open-label phase III randomized controlled trial, we will evaluate whether sirolimus-coated balloon angioplasty is non-inferior and eventually superior, according to a predefined hierarchical analysis, to uncoated balloon angioplasty in adults with infra-inguinal peripheral arterial disease requiring endovascular angioplasty. Key exclusion criteria are pregnancy or breastfeeding, known intolerance or allergy to sirolimus, and participation in a clinical trial during the previous 3 months. The primary efficacy outcome is the composite of two clinically relevant non-subjective "hard" outcomes: unplanned major amputation of the target limb and endovascular or surgical target lesion re-vascularization for critical limb ischemia occurring within 1 year of randomization. The primary safety outcome includes death from all causes. DISCUSSION: By focusing on clinically relevant outcomes, this study will provide useful information on the efficacy and safety of sirolimus-coated balloon catheters for infra-inguinal peripheral arterial disease in a representative ("all-comer") population of unselected patients. As regulatory agencies had raised safety concerns in patients exposed to paclitaxel-coated devices (versus uncoated ones), collect mortality data up to 5 years after randomization will be collected

Sirt1 inhibition promotes in vivo arterial thrombosis and tissue factor expression in stimulated cells

Aims The mammalian silent information regulator-two 1 (Sirt1) blunts the noxious effects of cardiovascular risk factors such as type 2 diabetes mellitus and obesity. Nevertheless, the role of Sirt1 in regulating the expression of tissue factor (TF), the key trigger of coagulation, and arterial thrombus formation remains unknown. Methods and results Human as well as mouse cell lines were used for in vitro experiments, and C57Bl/6 mice for in vivo procedures. Sirt1 inhibition by splitomicin or sirtinol enhanced cytokine-induced endothelial TF protein expression as well as surface activity, while TF pathway inhibitor protein expression did not change. Sirt1 inhibition further enhanced TF mRNA expression, TF promoter activity, and nuclear translocation as well as DNA binding of the p65 subunit of nuclear factor-kappa B (NFκB/p65). Sirt1 siRNA enhanced TF protein and mRNA expression, and this effect was reduced in NFκB/p65−/− mouse embryonic fibroblasts reconstituted with non-acetylatable Lys310-mutant NFκB/p65. Activation of the mitogen-activated protein kinases p38, c-Jun NH2-terminal kinase, and p44/42 (ERK) remained unaffected. In vivo, mice treated with the Sirt1 inhibitor splitomicin exhibited enhanced TF activity in the arterial vessel wall and accelerated carotid artery thrombus formation in a photochemical injury model. Conclusion We provide pharmacological and genetic evidence that Sirt1 inhibition enhances TF expression and activity by increasing NFκB/p65 activation in human endothelial cells. Furthermore, Sirt1 inhibition induces arterial thrombus formation in vivo. Hence, modulation of Sirt1 may offer novel therapeutic options for targeting thrombosi