34 research outputs found

    Prosthesis-patient mismatch after aortic valve replacement in the PARTNER 2 trial and registry

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    Objectives This study aimed to compare incidence and impact of measured prosthesis-patient mismatch (PPMM) versus predicted PPM (PPMP) after surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR). Background TAVR studies have used measured effective orifice area indexed (EOAi) to body surface area (BSA) to define PPM, but most SAVR series have used predicted EOAi. This difference may contribute to discrepancies in incidence and outcomes of PPM between series. Methods The study analyzed SAVR patients from the PARTNER (Placement of Aortic Transcatheter Valves) 2A trial and TAVR patients from the PARTNER 2 SAPIEN 3 Intermediate Risk registry. PPM was classified as moderate if EOAi ≤0.85 cm2/m2 (≤0.70 if obese: body mass index ≥30 kg/m2) and severe if EOAi ≤0.65 cm2/m2 (≤0.55 if obese). PPMM was determined by the core lab–measured EOAi on 30-day echocardiogram. PPMP was determined by 2 methods: 1) using normal EOA reference values previously reported for each valve model and size (PPMP1; n = 929 SAVR, 1,069 TAVR) indexed to BSA; and 2) using normal reference EOA predicted from aortic annulus size measured by computed tomography (PPMP2; n = 864 TAVR only) indexed to BSA. Primary endpoint was the composite of 5-year all-cause death and rehospitalization. Results The incidence of moderate and severe PPMP was much lower than PPMM in both SAVR (PPMP1: 28.4% and 1.2% vs. PPMM: 31.0% and 23.6%) and TAVR (PPMP1: 21.0% and 0.1% and PPMP2: 17.0% and 0% vs. PPMM: 27.9% and 5.7%). The incidence of severe PPMM and severe PPMP1 was lower in TAVR versus SAVR (P < 0.001). The presence of PPM by any method was associated with higher transprosthetic gradient. Severe PPMP1 was independently associated with events in SAVR after adjustment for sex and Society of Thoracic Surgeons score (hazard ratio: 3.18;95% CI: 1.69-5.96; P < 0.001), whereas no association was observed between PPM by any method and outcomes in TAVR. Conclusions EOAi measured by echocardiography results in a higher incidence of PPM following SAVR or TAVR than PPM based on predicted EOAi. Severe PPMP is rare (<1.5%), but is associated with increased all-cause death and rehospitalization after SAVR, whereas it is absent following TAVR

    Role of inorganics on the biomass char gasification reactivity: A review involving reaction mechanisms and kinetics models

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    International audienceThis review article presents the effects of the inorganic elements and compounds on gasification and their mechanisms of action. The influence of inorganics on the gasification reaction have been described in the literature. However, the specific phenomena involved and the mechanisms of action are not stated with consensus. Therefore, the present review gathers the various mechanisms proposed by authors. Some have been demonstrated to be unlikely such as the mechanisms involving intercalation compounds or mechanical actions. In order to give more practical applications of this work, the review also gathers the gasification kinetic models that take these inorganic effects into account

    The influence of char preparation and biomass type on char steam gasification kinetics

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    A study was conducted to investigate the parameter that has influence on steam gasification kinetics between the biomass type and char preparation. Thermogravimetric analysis (TGA) was carried out on steam gasification of seven biomass samples as well as chars from three of these samples. Chars were prepared using three different sets of low heating rate (LHR) pyrolysis conditions including temperature and biomass bed geometry. It was shown by a characteristic time analysis that these pyrolysis conditions were not associated with a chemical regime in a large amount of devices. However, it has been shown experimentally that conditions used to prepare the char had a much lower influence on steam gasification kinetics than the biomass type

    Thirty-day outcomes of the Cardioband tricuspid system for patients with symptomatic functional tricuspid regurgitation: The TriBAND study.

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    BACKGROUND Severe tricuspid regurgitation (TR) has limited treatment options and is associated with high morbidity and mortality. AIMS We evaluated the safety and effectiveness of the Cardioband tricuspid valve reconstruction system from the ongoing European single-arm, multicentre, prospective TriBAND post-market clinical follow-up study. METHODS Eligible patients had chronic symptomatic functional TR despite diuretic therapy and were deemed candidates for transcatheter tricuspid repair by the local Heart Team. RESULTS Sixty-one patients had ≥severe functional TR. At baseline, 85% of patients were in NYHA Class III-IV, 94% had ≥severe TR (core laboratory-assessed) with 6.8% EuroSCORE II and 53% LVEF. Device success was 96.7%. At discharge, 59% (p<0.001) of patients achieved ≤moderate TR and 78% had at least one grade TR reduction. At 30 days, all-cause mortality and composite MAE rates were 1.6% and 19.7%, respectively; septolateral annular diameter was reduced by 20%, where 69% of patients achieved ≤moderate TR and 85% of patients had at least one grade TR reduction (all p<0.001). Mid-RVEDD, RA volume, and IVC diameter decreased by 10% (p=0.005), 21% (p<0.001), and 11% (p=0.022), respectively; 74% were in NYHA Class I-II (p<0.001) with improvements in overall KCCQ score by 17 points (p<0.001). CONCLUSIONS In the TriBAND study, the Cardioband tricuspid system demonstrated favourable outcomes at discharge and 30 days in a challenging patient population with symptomatic ≥severe functional TR. Results showed significant reductions in annular diameter and TR severity, accompanied by early evidence of right heart remodelling and improvements in functional status and quality of life
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