Vascular Implantation Research Articles

Long-term Outcomes Associated With Open vs Endovascular Abdominal Aortic Aneurysm Repair in a Medicare-Matched Database

Endovascular aneurysm repair is associated with a significant reduction in perioperative mortality and morbidity compared with open aneurysm repair in the treatment of abdominal aortic aneurysm. However, this benefit decreases over time owing to increased reinterventions and late aneurysm rupture after endovascular repair. To compare long-term outcomes of endovascular vs open repair of abdominal aortic aneurysm. This multicenter retrospective cohort study used deidentified data with 6-year follow-up from the Medicare-matched Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database. Patients undergoing first-time elective endovascular or open abdominal aortic aneurysm repair from 2003 to 2018 were propensity score matched. Patients with ruptured abdominal aortic aneurysm, concomitant procedures, or prior history of abdominal aortic aneurysm repair, were excluded. Data were analyzed from January 1, 2003, to December 31, 2018. First-time elective endovascular or open repair for abdominal aortic aneurysm. The primary long-term outcome of interest was 6-year all-cause mortality, rupture, and reintervention. Secondary outcomes included 30-day mortality and perioperative complications. Among a total of 32 760 patients (median [IQR] age, 75 [70-80] years; 25 706 [78.5%] men) who underwent surgical abdominal aortic aneurysm repair, 28 281 patients underwent endovascular repair and 4479 patients underwent open repair. After propensity score matching, there were 2852 patients in each group. Open repair was associated with significantly lower 6-year mortality compared with endovascular repair (548 deaths [35.6%] vs 608 deaths [41.2%]; hazard ratio [HR], 0.83; 95% CI, 0.74-0.94; P = .002), with increases in mortality starting from 1 to 2 years (84 deaths [4.3%] vs 126 deaths [6.7%]; HR, 0.63; 95% CI, 0.48-0.83; P = .001) and 2 to 6 years (211 deaths [25.8%] vs 241 deaths [30.6%]; HR, 0.73; 95% CI, 0.61-0.88; P = .001). Open repair, compared with endovascular repair, also was associated with significantly lower rates of 6-year rupture (117 participants [5.8%] vs 149 participants [8.3%]; HR, 0.76; 95% CI, 0.60-0.97; P < .001) and reintervention (190 participants [11.6%] vs 267 participants [16.0%]; HR, 0.67; 95% CI, 0.55-0.80; P < .001). Open repair was associated with significantly higher odds of 30-day mortality (OR, 3.56; 95% CI, 2.41-5.26; P < .001) and complications. These findings suggest that overall mortality after elective abdominal aortic aneurysm repair was higher with endovascular repair than open repair despite reduced 30-day mortality and perioperative morbidity after endovascular repair. Endovascular repair additionally was associated with significantly higher rates of long-term rupture and reintervention. These findings emphasize the importance of careful patient selection and long-term follow-up surveillance for patients who undergo endovascular repair.

Effects of aggressive predilatation, sizing, and postdilatation strategy for coronary bioresorbable vascular scaffolds implantation.

The results of the recent Amsterdam Investigator-Initiated Absorb Strategy All-Comers trial showed that the predilatation, sizing, and postdilatation (PSP) technique did not lower the long-term rates of scaffold thrombosis and adverse events. We evaluated the impact of aggressive PSP bioresorbable vascular scaffold (BRS) implantation on the short- and long-term clinical outcomes. From June 2014 to December 2016, 150 patients with BRS implantation were enrolled and received successful percutaneous coronary intervention (PCI), of whom 104 received aggressive PSP technique (high-pressure predilatation and lesion preparation in addition to the traditional PSP technique). Short- and long-term outcomes were compared. All patients underwent successful PCI and BRS implantation with final Thrombolysis in Myocardial Infarction grade 3 flow. The baseline and procedure characteristics were similar in both groups. Debulking techniques were used in 13 (8.7%) patients. Intracoronary imaging modalities were used in 73 (48.7%) patients. After BRS implantation, no adverse events were observed within 30 days in both groups. During the mean follow-up period of 2.98 ± 0.77 years, 12 (8.0%) patients experienced major adverse cardiovascular events (MACEs), including one cardiovascular death (0.6%), three nonfatal myocardial infarction (2.0 %), and 11 target-vessel revascularization (7.3 %). Multivariate Cox regression analysis showed that aggressive PSP remained an independent protective factor for MACEs. Moreover, the use of intracoronary imaging and rotablation atherectomy was associated with better clinical outcomes. Lesion preparation by aggressive PSP in BRS implantation was associated with better long-term clinical outcomes.

Does a small-diameter rod-type tunneler reduce postoperative swelling? An evaluation using a canine arteriovenous graft model.

Sheath-type tunnelers are frequently used to create vascular access using vascular grafts. However, during vascular access creation, tunnelers damage the surrounding tissues, consequently causing problems, such as swelling, failure to heal, and infection. This study evaluated a novel rod-type tunneler that was designed to prevent tunneler-related tissue damage and its sequelae. We developed a small-diameter rod-type tunneler that reduces injuries during subcutaneous tunnel creation. The rod diameter of this tunneler is smaller than the vascular graft diameter being implanted. It has a structure in which a vascular graft is implanted at a target site by grasping and pulling the vascular graft. Three dogs were used in the experiment, and arteriovenous grafts were created using a rod-type and a sheath-type tunneler on the left and right thighs, respectively, with a different type of commercially available graft used in each dog. The edema of the tissues surrounding the vascular graft was measured at 11 sites by ultrasonography at prespecified intervals. Compared with implantation using a sheath-type tunneler, when the self-sealing Rapidax II was implanted using the small-diameter rod-type tunneler, the postimplantation edema (degree of change) decreased by 28-53% and 80-247% in the peri-vascular-graft area and within the loop, respectively. The MAXIFLO and SEALPTFE did not significantly reduce postoperative edema but exhibited a tendency for improved postimplantation tissue healing. The reduced-diameter rod-type tunneler may be a useful device for vascular graft implantation.

Tellurium-containing polymer coating with glutathione peroxidase mimics capability for surface modification of intravascular implants

Interventional therapy as an effective method has saved millions of lives of human, in which the interventional devices (e.g. central venous catheters, vascular stent, etc.) play a crucial role. However, undesirable implantation responses including thrombus formation, inflammation, and hyperplasia is still the life-threatening to the patients. In this study, a novel tellurium-functionalized polycarbonate-polyurethane (PCU-TeTe) was designed and synthesized by introducing ditelluride bonds (Te-Te) into the molecular structure of polymer. The developed PCU-TeTe showed an excellent catalytic activity in the nitric oxide (NO) release with a rate of 2.8 × 10-10 mol·cm−2·min−1, hence has multiple advanced functions in the blood environment. Both in vitro and ex vivo results of hemocompatibility showed that PCU-TeTe could substantially reduce the probability of thrombogenesis. Besides, PCU-TeTe could significantly promote endothelial cell (EC) proliferation while suppress the growth of smooth muscle cell (SMC) and macrophage (MA). Moreover, the in vivo results including qualitative and quantitative date (e.g. abdominal aorta hyperplasia) demonstrated that PCU-TeTe could not only promote healthy endothelialization, but also inhibit thrombus, inflammation and hyperplasia. Such tellurium-functionalized system could be a promising strategy for the design and fabrication of vascular materials or implants, especially for blood-contacting devices in the future.

Analysis of Functionalized Ferromagnetic Memory Alloys from the Perspective of Developing a Medical Vascular Implant

Durable biocompatible metal vascular implants are still one of the significant challenges of contemporary medicine. This work presents the preparation of ferromagnetic biomaterials with shape memory in metal strips based on FePd (30 at% Pd) that is either not doped or doped with Ga and Mn, coated with poly(benzofuran-co-arylacetic acid) or polyglutamic acid. The coating of the metal strips with polymers was achieved after the metal surface had been previously treated with open-air cold plasma. The final functionalization was performed to induce anti-thrombogenic/thrombolytic properties in the resulting materials. SEM-EDX microscopy and X-ray photoelectron microscopy (XPS) determined the morphology and composition of the metal strips covered with polymers. In vitro tests of standardized thromboplastin time (PTT) and prothrombin time (PT) were performed to evaluate the thrombogenicity of these biofunctionalized materials for future possible monitoring of the implant in patients.

Contemporary incidence, outcomes, and survival associated with endovascular aortic aneurysm repair conversion to open repair among Medicare beneficiaries

ObjectiveThe widespread application of endovascular abdominal aortic aneurysm repair (EVAR) has ushered in an era of requisite postoperative surveillance and the potential need for reintervention. The national prevalence and results of EVAR conversion to open repair, however, remain poorly defined. The purpose of this analysis was to define the incidence of open conversion and its associated outcomes. MethodsThe SVS Vascular Quality Initiative EVAR registry linked to Medicare claims via Vascular Implants Surveillance and Interventional Outcomes Network was queried for open conversions after initial EVAR procedures from 2003 to 2016. Cumulative conversion incidence within up to 5 years after EVAR and outcomes after open intervention were determined. Multivariable logistic regressions were used to identify independent predictors of conversion and mortality. ResultsAmong 15,937 EVAR patients, 309 (1.9%) underwent an open conversion: 43% (n = 132) early (<30 days) and 57% (n = 177) late (>30 days). The longitudinally observed rate of conversion was constant over time, as well as by geographic region. Independent predictors of conversion included female sex (hazard ratio [HR], 1.49; P < .001), aneurysm diameter or more than 6.0 cm at the time of index EVAR (HR, 1.74; P < .001), nonelective repair (compared with elective presentation: HR, 1.72; P < .001), and aortouni-iliac repairs (HR, 2.19; P < .001). In contrast, adjunctive operative procedures such as endo-anchors or cuff extensions (HR, 0.62; P = .06) were protective against long-term conversion. Both early (HR, 1.6; P < .001) and late (HR, 1.26; P = .07) open conversions were associated with significant 30-day (total cohort, 15%) and 1-year mortality (total cohort, 25%). Patients undergoing open conversion experienced high rates of 30-day readmission (42%) and cardiac (45%), renal (32%), and pulmonary (30%) complications. ConclusionsThis large, registry-based analysis is among the first to document the incidence and outcomes for open conversion after EVAR in a national cohort with long-term follow-up. Importantly, women, patients with large aneurysms, and complex anatomy, as well as urgent or emergent EVARs are at an increased risk for open conversion. It seems that more conversions are performed in the early postoperative period, despite perceptions that conversion is a delayed phenomenon. In all instances, conversion is associated with significant morbidity and mortality and highlights the importance of appropriate patient selection at the time of index EVAR.

In-hospital complications and long-term outcomes associated with timing of carotid endarterectomy

ObjectiveCarotid revascularization performed within 2 weeks of symptoms has proven to reduce risk of recurrent stroke in patients with symptomatic carotid artery stenosis. However, the optimal timing of revascularization within the 2-week window has yet to be determined. The objective of this study was to perform a comprehensive analysis of in-hospital and long-term outcomes of carotid endarterectomy (CEA) performed within different time intervals after most recent symptoms. MethodsWe analyzed 2003 to 2016 data from the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network. Only revascularizations performed for symptomatic carotid artery stenosis were included. Procedures were categorized as urgent (0-2 days from latest symptom), early (3-14 days), or late (15-180 days). The primary in-hospital outcome was stroke/death. The primary long-term outcomes of interest were 5-year recurrent ipsilateral stroke/death. Multivariable logistic regression, Kaplan-Meier analysis, and Cox regression were utilized to compare outcomes. ResultsA total of 18,970 revascularizations were included: 1130 (6.0%) urgent, 4643 (24.5%) early, and 13,197 (69.6%) late. Earlier CEA had increased odds of in-hospital stroke/death compared with late CEA (urgent: adjusted odds ratio, 1.9; 95% confidence interval [CI], 1.3-2.8; P = .001; early: adjusted odds ratio, 1.7; 95% CI, 1.3-2.2; P < .001). No differences were seen in 5-year risk of stroke/death (urgent: adjusted hazard ratio, 0.95; 95% CI, 0.79-1.15; P = .592; early: adjusted hazard ratio, 0.97; 95% CI, 0.87-1.07; P = .928). ConclusionsUrgent and early CEA were associated with increased perioperative risk without difference in 5-year outcomes compared with late CEA. Short-term recurrent stroke prevention could not be assessed. Updated population-based studies comparing recurrent stroke prevention with urgent or early revascularization vs best medical management are warranted.

Structure design and mechanical performance analysis of three kinds of bioresorbable poly-lactic acid (PLA) stents

Vascular stent implantation has become an important choice for the treatment of severe cardiovascular and cerebrovascular blockage. Rational design is vital to ensure the mechanical properties of the vascular stents, which are important both to the implantation and service as for clinical treatment of coronary heart disease. Therefore we proposed a wholly new non-uniform honeycomb stent E and compared with an inverted honeycomb-like shaped stent F and a honeycomb-like shaped stent G. To evaluate their properties, a finite element method (FEM) was used to simulate the implantation process (crimp, crimp recoil, expand, and expand recoil) of these three different kinds of stents. Results showed that the stent E exhibits better mechanical behaviour than the other two stents F and G as far as radial strength and axial shortening performances and that the distribution of equivalent stress among the stent E is more uniform than that among the other two stents F and G. After that, a three-point bending method was used to study the bending flexibility of these three vascular stents. Stent E shows high bending stiffness compared with stents F and G due to the existence of additional support bridges in its structure. This study can be helpful to the rational design of optimizable PLA stents for its practical clinical performance and therefore possibly improve the prognosis of patients.

Electrochemical Corrosion Behaviour Analysis of Mg-Alloys Used for Orthopaedics and Vascular Implants

Mg-alloys having bone liked mechanical properties are biodegradable, biocompatible and osteoconductive metallic materials are potential candidates used for orthopaedics and vascular implants. Therefore, present experimentation is an effort to analyse the corrosion behaviour of Mg based alloys such as AZ81 and ZM21 for their usage as bio-degradable implant materials. The corrosion behaviour is analysed using the electrochemical workstation. SEM and EDS are used for high-resolution images and composition of magnesium-based alloys. Using Potentiodynamic polarization curves and Nyquist plots, corrosion rates were observed for 3.0 hours studies on ZM21(193.53 mm/year) and AZ81 (24.22 mm/year) for Mg-alloys. AZ81 shows higher corrosion resistance than ZM21. The results of these experimental findings may be helpful for the designers and researchers in selecting and improving the clinical performance of Mg-based implants for biomedical applications.

Mechanisms of Calcification in Materials for Valvular and Vascular In Situ Tissue Engineering

Objective: In situ tissue engineering (TE) of vascular and valvular graft implants has rapidly progressed over the past two decades as it prospects a great alternative to autologous, xenografted, and non-biological materials for vessel and valve replacements. In this approach, a synthetic degradable valve or vessel replacement is implanted at the site of a diseased valve or vessel, where it gradually remodels into viable tissue.1 However promising, some possible challenges need to be assessed to ensure safe clinical translation of this technique.

Vascular implants - new aspects for in situ tissue engineering.

Conventional synthetic vascular grafts require ongoing anticoagulation, and autologous venous grafts are often not available in elderly patients. This review highlights the development of bioartificial vessels replacing brain‐dead donor‐ or animal‐deriving vessels with ongoing immune reactivity. The vision for such bio‐hybrids exists in a combination of biodegradable scaffolds and seeding with immune‐neutral cells, and here different cells sources such as autologous progenitor cells or stem cells are relevant. This kind of in situ tissue engineering depends on a suitable bioreactor system with elaborate monitoring systems, three‐dimensional (3D) visualization and a potential of cell conditioning into the direction of the targeted vascular cell phenotype. Necessary bioreactor tools for dynamic and pulsatile cultivation are described. In addition, a concept for design of vasa vasorum is outlined, that is needed for sustainable nutrition of the wall structure in large caliber vessels. For scaffold design and cell adhesion additives, different materials and technologies are discussed. 3D printing is introduced as a relatively new field with promising prospects, for example, to create complex geometries or micro‐structured surfaces for optimal cell adhesion and ingrowth in a standardized and custom designed procedure. Summarizing, a bio‐hybrid vascular prosthesis from a controlled biotechnological process is thus coming more and more into view. It has the potential to withstand strict approval requirements applied for advanced therapy medicinal products.

Dissections after bioresorbable vascular scaffold implantation in the POLAR ACS Registry.

IntroductionPercutaneous coronary intervention (PCI) is a common method of treatment for patients with coronary artery disease. One of the most common complications during the PCI procedure is coronary artery dissection. It usually requires an additional action to assure the patency of the treated vessel.AimThe aim of the publication is to describe the occurrence of coronary artery dissection after bioresorbable vascular scaffold (BVS) implantation. This selected type of PCI procedure is especially interesting because precise target vessel measurement before BVS implantation is required for optimal determination of scaffold size.Material and methodsBased on angiographic data gathered in the POLAR ACS Registry, we assessed the frequency of dissections, their localization, and severity. Based on data regarding patients’ demographic, clinical status, and details regarding treatment strategy, the factors that could have an influence on the dissection occurrence were identified.ResultsA group of 100 patients included in the analyses. Group A consisted of 9 patients. This group was defined as patients in whom the significant dissection occurred after the BVS implantation. Group B comprised 91 patients. Both groups were very similar according to demographic data. The frequency of predilatation was similar; post-dilatation was performed more often in group A but without statistical significance. The presence of calcification in the target lesion was an independent factor of dissection during the index PCI procedure.ConclusionsThe occurrence of significant dissection can be effectively treated, and the good angiographic results of this treatment immediately after the initial procedure translate into good clinical results in longer follow-up.

Genetic Factors of Idiopathic Recurrent Miscarriage in Kazakh Population.

Background:It seems that 50% of the possible causes of recurrent miscarriage do not have any explainable etiology and they require in-depth etiopathogenesis analysis. The purpose of this research was to study polymorphisms relationship of the immune response genes including Val249Ile CX3CR1 (rs3732379), CT60 G/A CTLA4 (rs3087243), and HLA DQA1, DQB1, DRB1 (major histocompatibility complex, class II) with development of idiopathic form of recurrent miscarriage (iRM) in Kazakh population.Methods:TagMan genotyping for 302 patients with iRM and 300 women with normal reproduction was performed. Molecular genetic studies were carried out by the TaqMan method of unified site-specific amplification and real-time genotyping using test systems. Statistical tests and Chi Square were carried out using PLINK, STATA13 software and p<0.05 was considered statistically significant.Results:It has been shown that carriage of unfavorable genotypes (Val/Ile, Val/Val) by the Val249Ile polymorphism of CX3CR1 gene increases the risk of developing iRM by 1.43 times. Search for associations of genes allelic variants of HLA class 2 complex with iRM revealed 501 allele in DQA1 locus, 0301 in DQB1 locus, 10, 12, 15, 16 alleles in DRB1 locus, which increase the risk of developing iRM in Kazakh population.Conclusion:The highly significant associations of immune response genes with development of iRM in Kazakh population indicate the possible involvement of the immune system interaction of mother cells with syncytiotrophoblast, which is realized by vascular defects and defective embryo implantation, causing termination of pregnancy.

Hierarchical-structured bacterial cellulose/potato starch tubes as potential small-diameter vascular grafts

To achieve long-term patent small-diameter (<6 mm) vascular implants, biomimetic vascular grafts have gained much attention in promoting in situ blood vessel regeneration. In this study, hierarchical-structured bacterial cellulose/potato starch (BC/PS) composites were biosynthesized by the addition of swollen PS. Investigations on the physicochemical properties of BC/PS composites showed that the properties could be improved and tailored by the addition of swollen PS. The composites displayed a morphology, water content, thermal properties, mechanical properties, and biocompatibility appropriate for vascular tissue engineering. Most importantly, the BC/PS grafts, with a dense inner surface and a circumferential macroporous outer layer, possessed 75% patency and promoted rapid blood vessel regeneration in in vivo assessment on rabbits, with complete endothelium monolayer, organized smooth muscle cells, rich new capillaries, and deposited extracellular matrix. Collectively, these findings demonstrate that hierarchical-structured BC/PS tubes hold great promise as artificial small-diameter vascular grafts.

Evaluation of the Effectiveness of Modified Pectoral Nerve Blocks Type II (PECS II) for Vascular Access Port Implantation Using Cephalic Vein Venesection.

The vascular access port implantation procedure can be performed using the venesection method by inserting a catheter into the cephalic vein in the region of the deltopectoral groove. This method eliminates the need for catheter tunneling. An alternative method to infiltration anaesthesia for port implantation may be a modified pectoral nerve block type II (PECS II). This study aimed to evaluate the effectiveness of modified PECS II for vascular access port implantation using cephalic vein venesection. This retrospective observational study was conducted at the 4th Military Clinical Hospital in Wroclaw, Poland. A group of 114 patients underwent the modified PECS II block and additional cutaneous infiltration anesthesia at the incision line. Pain intensity was assessed on the NRS scale measured intraoperatively at four points. The QoR-15 questionnaire was used to assess patient satisfaction during the first 24 h after surgery. The operator’s condition assessment score was used to assess surgical conditions and operator comfort. The analysis showed that the median pain intensity during vascular port implantation was 0. A statistically significant difference in pain intensity was demonstrated between the specialist’s group and the resident’s group at the second and third measurement points (p < 0.008; p < 0.012). The mean value on the QoR-15 scale was 132. There was a significant difference between the pain scores of the groups. The mean score in the pain position in the specialist’s group was 18 points and in the resident’s group, it was 19 points (p < 0.029). In conclusion, the present study revealed that the modified PECS II block is an effective and safe method of anesthesia for Port-A-Cath implantation.

A tough nitric oxide-eluting hydrogel coating suppresses neointimal hyperplasia on vascular stent

Vascular stent is viewed as one of the greatest advancements in interventional cardiology. However, current approved stents suffer from in-stent restenosis associated with neointimal hyperplasia or stent thrombosis. Herein, we develop a nitric oxide-eluting (NOE) hydrogel coating for vascular stents inspired by the biological functions of nitric oxide for cardiovascular system. Our NOE hydrogel is mechanically tough and could selectively facilitate the adhesion of endothelial cells. Besides, it is non-thrombotic and capable of inhibiting smooth muscle cells. Transcriptome analysis unravels the NOE hydrogel could modulate the inflammatory response and induce the relaxation of smooth muscle cells. In vivo study further demonstrates vascular stents coated with it promote rapid restoration of native endothelium, and persistently suppress inflammation and neointimal hyperplasia in both leporine and swine models. We expect such NOE hydrogel will open an avenue to the surface engineering of vascular implants for better clinical outcomes.

To Analyze the Causes, Mechanisms and Preventive Methods of Complications after Cerebral Vascular Stent Implantation

To Analyze the Causes, Mechanisms and Preventive Methods of Complications after Cerebral Vascular Stent Implantation

Abstract 12996: Prospective Study of Patient Reported Outcomes and Costs Associated With Same Day Discharge and Vascular Closure for Atrial Fibrillation Ablation

Introduction: Overnight stay after ablation for atrial fibrillation (AF) is standard practice, in part driven by the need for bedrest required to maintain hemostasis. We aimed to measure patient reported outcomes (PROs) and costs associated with same day discharge (SDD) for AF ablation and vascular closure device implantation in clinical practice. Methods: PROs were measured in 50 patients prospectively enrolled prior to AF ablation with post procedure treatment by complete vascular device closure (n=25) versus compression hemostasis (n=25). Health-system costs for SDD patients receiving vascular device closure were compared to matched controls with one-night stays who did not receive closure devices. Results: Patients receiving vascular device closure for AF ablation had mean age 65, 17% female, with mean CHA 2 DS 2 -VASc score 3. Mean number of venous sheaths was higher among patients receiving vascular device closure (3.8 vs. 3.1, p&lt;0.001), and there was 1 case of re-bleeding in a patient receiving vascular closure device (no other vascular complications). Same-day discharge rates (76% vs. 8.3%, p&lt;0.001), patient satisfaction with bedrest time (8.5 vs. 6, p=0.004) and with pain (8 vs. 5.1, p=0.009) were significantly higher among patients receiving vascular closure. For health-system costs, patients with vascular closure the mean age was 66, 36% were female, with a mean CHA 2 DS 2 -VASc score of 2 (p=NS for each vs. matched controls). SDD with vascular closure was associated with significantly lower facility, pharmacy, and disposable costs, but higher implant costs ( Table ). Overall costs for ablation were not different based on conservative estimates for overnight stay costs. Conclusions: Vascular closure for AF ablation improves patient experience in routine clinical care. Use of vascular closure and SDD after AF ablation reduces several components of health system costs, without an overall increase, and may be cost-saving in comparative healthcare systems.

Abstract 10514: Inguinal Fat Tissue Biopsy to Identify Transthyretin Amyloidosis in Patients Undergoing Transcatheter Aortic Valve Implantation

Background: Several studies have recently reported that transthyretin (ATTR) amyloidosis is present in patients with aortic stenosis (AS). This study aimed to 1) examine the utility of inguinal fat tissue biopsy in AS patients who underwent transcatheter aortic valve implantation (TAVI) to detect ATTR amyloidosis, 2) compare clinical characteristics between AS patients with ATTR (ATTR group) and those without ATTR (non-ATTR group). Methods and Results: We prospectively analyzed consecutive 56 patients who underwent transfemoral TAVI from December 2018 to December 2020 in our hospital. To screen ATTR in these patients, we performed inguinal fat tissue biopsy from cut down or puncture site during TAVI. Of 56 AS patients, 5 (8.9%) patients were diagnosed as ATTR by inguinal fat biopsy. Compared with non-ATTR group, ATTR group presented higher levels of B-type natriuretic peptide (BNP, 566.4 vs. 242.5 ng/ml, P=0.0045), higher levels of troponin I (0.053 vs. 0.024 ng/ml, P=0.003), lower left ventricular ejection fraction (LVEF, 49.3 vs. 60.3%, P=0.0035), larger left ventricular mass index (150.2 vs. 115.5 g/m 2 , P=0.019), larger aortic valve area (0.84 vs. 0.63 cm 2 , P=0.029) and lower peak velocity of aortic valve (3.8 vs. 4.4 m/s, P=0.041). In contrast, age, sex, STS score, clinical frailty scale, prevalence of diabetes, chronic kidney disease and AF, levels of albumin, and eGFR were comparable between the two groups. Electrocardiogram and other echocardiographic parameters including interventricular septal wall thickness, posterior wall thickness, stroke volume index and E/A ratio did not differ between the two groups. Although TAVI was successfully completed in all patients, the incidence of life-threatening bleeding and 30-day readmission was higher in ATTR group than in non-ATTR group (40.0 vs. 5.9%, P=0.011 and 20.0 vs. 0.0%, P=0.001). There was no difference in occurrence of myocardial infarction, stroke, acute kidney injury, major vascular complication, pacemaker implantation and 30-day mortality. Conclusions: In AS patients, especially in those with increased BNP and troponin I levels and low-flow low-gradient pattern, ATTR should be considered. In this population, inguinal fat tissue biopsy is a novel and safe approach to identify ATTR.

Bio-Performance of Hydrothermally and Plasma-Treated Titanium: The New Generation of Vascular Stents.

The research presented herein follows an urgent global need for the development of novel surface engineering techniques that would allow the fabrication of next-generation cardiovascular stents, which would drastically reduce cardiovascular diseases (CVD). The combination of hydrothermal treatment (HT) and treatment with highly reactive oxygen plasma (P) allowed for the formation of an oxygen-rich nanostructured surface. The morphology, surface roughness, chemical composition and wettability of the newly prepared oxide layer on the Ti substrate were characterized by scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) analysis. The alteration of surface characteristics influenced the material’s bio-performance; platelet aggregation and activation was reduced on surfaces treated by hydrothermal treatment, as well as after plasma treatment. Moreover, it was shown that surfaces treated by both treatment procedures (HT and P) promoted the adhesion and proliferation of vascular endothelial cells, while at the same time inhibiting the adhesion and proliferation of vascular smooth muscle cells. The combination of both techniques presents a novel approach for the fabrication of vascular implants, with superior characteristics.