209 research outputs found
Serial Morphological and Functional Assessment of Drug-Eluting Balloon for In-Stent Restenotic Lesions Mechanisms of Action Evaluated With Angiography, Optical Coherence Tomography, and Fractional Flow Reserve
ObjectivesThis study sought to elucidate the underlying mechanism through which drug-eluting balloons (DEB) restore coronary blood flow, by assessing the coronary vessel before, immediately after, and at 6-month follow-up with angiography, optical coherence tomography (OCT), and fractional flow reserve (FFR).BackgroundIn-stent restenosis (ISR) treatment remains challenging. Drug-eluting balloons have been shown to be a valid treatment option in several studies. These studies focused on efficiency of the device, whereas the mechanisms of action of DEB in ISR treatment have not been investigated.MethodsIn this prospective, single-center observational study, patients with ISR were treated with a second-generation DEB. Serial angiographic, OCT, and FFR measurements were performed before and after the procedure, as well as at 6-month follow-up.ResultsTwenty-five patients were assigned to DEB treatment, with an angiographic and device success of 100% and 92%, respectively. Late luminal loss was 0.01 ± 0.43 mm. Median percent changes [interquartile range] between pre-and post-procedure, and post-procedure and follow-up were, respectively: lumen volume 75.1% increase [43.7 to 115.0], and 8% increase [−14.0 to 25.8]; stent volume 23.7% increase [15.5 to 40.0], and −1.2% decrease [−6.9 to 5.9]; and neointimal volume −14.4% decrease [−29.2 to −9.5], and −15.8% decrease [−38.1 to 28.3]. The FFR gradient along the treated stent (difference in FFR between the distal and the proximal stent edge) was 0.37 ± 0.18 pre-procedure, 0.06 ± 0.04 post-procedure, and 0.05 ± 0.05 at follow-up. In all post-procedural OCT images, intrastent dissections were seen, which were sealed at follow-up OCT.ConclusionsDEB restore coronary blood flow by means of a short-term mechanical effect, causing an increase in lumen and stent volumes and compression of neointimal hyperplasia (with intra-stent dissections). Due to the local drug effect, patency persists and may even improve at follow-up, with further increase in lumen volume, decrease in neointimal volume, and complete sealing of neointimal dissections
Расчет электромагнитного поля в электронных модулях с использованием интеграла Зоммерфельда
Излагается подход с использованием интеграла Зоммерфельда. Метод позволяет избежать интегрирования в комплексной области и снизить объем вычислений по сравнению с известными методами
Randomized comparison between 3-month Cre8 DES vs. 1-month Vision/Multilink8 BMS neointimal coverage assessed by OCT evaluation: The DEMONSTRATE study
AbstractBackgroundIt has been hypothesized that incomplete endothelialization and delayed vascular healing may trigger stent thrombosis events after drug-eluting stent (DES) implantation. We aimed to demonstrate non-inferiority in terms of neointimal coverage of novel Cre8 DES at 3months, compared to Vision/Multilink8 Bare Metal Stent (BMS) at 1month.MethodsThe ranDomizEd coMparisOn betweeN novel Cre8 DES and BMS to assess neoinTimal coveRAge by OCT Evaluation (DEMONSTRATE) was a multicenter, randomized, parallel group study. Thirty-eight patients undergoing angioplasty of de-novo coronary lesion were randomized to Cre8 (19) or Vision/Multilink8 (19) stent placement at 6 OCT-experienced centers. Primary end-point was the Ratio of Uncovered to Total Stent Struts Per Cross Section (RUTTS) score of <30%, determined by OCT at 3 and 1months for Cre8 and Vision/Multilink8, respectively. Percentage of uncovered/malapposed stent struts, neointimal growth and thickness were the main secondary end-points.ResultsThe primary end-point of RUTTS score <30% occurred in 99.8% (899/901) of Cre8 struts and in 99.6% (1116/1121) of Vision/Multilink8 struts (difference 0.2, CI 95% −0.2 to 0.6, p for noninferiority <0.001). The percentage of uncovered/malapposed struts was comparable (0.36±0.64 vs. 0.12±0.24, p=0.145) in the two study groups, while both neointimal percentage area (8.46±5.29 vs. 19.84±15.93, p<0.001) and thickness (0.07±0.04 vs. 0.16±0.12, p<0.001) were significantly reduced by Cre8 stent.ConclusionsThe Cre8 DES at 3months has comparable strut coverage to Vision/Multilink8 BMS at 1month while preserving a greater efficacy in neo-intima formation reduction. Further studies to assess clinical implication of these Cre8 characteristics are warranted
The impact of frailty on adverse outcomes after transcatheter aortic valve replacement in older adults: A retrospective cohort study
BACKGROUND: Transcatheter aortic valve replacement (TAVR) is an effective alternative to surgical aortic valve replacement for patients who are at increased surgical risk. Consequently, frailty is common in patients undergoing TAVR. OBJECTIVES: This study aims to investigate the impact of frailty on outcomes following TAVR. METHODS: A retrospective cohort study was conducted, including all TAVR candidates who visited the geriatric outpatient clinic for preoperative screening. Frailty status was assessed according to the Groningen Frailty Indicator. The primary outcome of the study was defined as the occurrence of postoperative complications, and this was evaluated according to the Clavien-Dindo classification. An additional analysis was performed to assess the impact of frailty on 1-year all-cause mortality and complications within 30 days of TAVR according to the Valve Academic Research Consortium (VARC-2) criteria. The VARC-2 criteria provide harmonized endpoint definitions for TAVR studies. RESULTS: In total, 431 patients with a mean age of 80.8 ± 6.2 years were included, of whom 56% were female. Frailty was present in 36% of the participants. Frailty was associated with a higher risk of the composite outcome of complications [adjusted odds ratio (OR): 1.55 (95% confidence interval, CI: 1.03-2.34)], 30-day mortality [adjusted OR: 4.84 (95% CI: 1.62-14.49)], 3-month mortality [adjusted OR: 2.52 (95% CI: 1.00-6.28)] and 1-year mortality [adjusted OR: 2.96 (95% CI: 1.46-6.00)]. CONCLUSIONS: Frailty is common in TAVR patients and is associated with an increased overall risk of postoperative complications, particularly mortality. Increased optimization of screening and treatment of frailty in the guidelines for valvular heart diseases is recommended
Late onset of new conduction disturbances requiring permanent pacemaker implantation following TAVI
Background: The timing of onset and associated predictors of late new conduction disturbances (CDs) leading to permanent pacemaker implantation (PPI) following transcatheter aortic valve implantation (TAVI) are still unknown, however, essential for an early and safe discharge. This study aimed to investigate the timing of onset and associated predictors of late onset CDs in patients requiring PPI (LCP) following TAVI. Methods and results: We performed retrospective analysis of prospectively collected data from five large volume centres in Europe. Post-TAVI electrocardiograms and telemetry data were evaluated in patients with a PPI post-TAVI to identify the onset of new advanced CDs. Early onset CDs were defined as within 48 hours after procedure, and late onset CDs as after 48 hours. A total of 2804 patients were included for analysis. The PPI rate was 12%, of which 18% was due to late onset CDs (>48 hours). Independent predictors for LCP were pre-existing non-specific intraventricular conduction delay, pre-existing right bundle branch block, self-expandable valves and predilation. At least one of these risk factors was present in 98% of patients with LCP. Patients with a balloon-expandable valve without predilation did not develop CDs requiring PPI after 48 hours. Conclusions: Safe early discharge might be feasible in patients without CDs in the first 48 hours after TAVI if no risk factors for LCP are present
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