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71.
Vinayak Bapat Vivek Rajagopal Christopher Meduri R. Saeid Farivar Antony Walton Stephen J. Duffy Robert Gooley Aubrey Almeida Michael J. Reardon Neal S. Kleiman Konstantinos Spargias Stratis Pattakos Martin K. Ng Michael Wilson David H. Adams Martin Leon Michael J. Mack Sharla Chenoweth Simon Redwood 《Journal of the American College of Cardiology》2018,71(1):12-21
Background
Transcatheter mitral valve replacement (TMVR) is a potential therapy for patients with symptomatic, severe mitral regurgitation (MR). The feasibility of this therapy remains to be defined.Objectives
The authors report their early experience with TMVR using a new valve system.Methods
The valve is a self-expanding, nitinol valve with bovine pericardial leaflets that is placed using a transapical delivery system. Patients with symptomatic MR who were deemed high or extreme risk by the local heart teams were enrolled in a global pilot study at 14 sites (United States, Australia, and Europe).Results
Fifty consecutively enrolled patients (mean age: 73 ± 9 years; 58.0% men; 84% secondary MR) underwent TMVR with the valve. The mean Society for Thoracic Surgery score was 6.4 ± 5.5%; 86% of patients were New York Heart Association functional class III or IV, and the mean left ventricular ejection fraction was 43 ± 12%. Device implant was successful in 48 patients with a median deployment time of 14 min (interquartile range: 12 to 17 min). The 30-day mortality was 14%, with no disabling strokes, or repeat interventions. Median follow-up was 173 days (interquartile range: 54 to 342 days). At latest follow-up, echocardiography confirmed mild or no residual MR in all patients who received implants. Improvements in symptom class (79% in New York Heart Association functional class I or II at follow-up; p < 0.0001 vs. baseline) and Minnesota Heart Failure Questionnaire scores (56.2 ± 26.8 vs. 31.7 ± 22.1; p = 0.011) were observed.Conclusions
TMVR with the valve was feasible in a study group at high or extreme risk for conventional mitral valve replacement. These results inform trial design of TMVR in lower-risk patients with severe mitral valve regurgitation (Evaluation of the Safety and Performance of the Twelve Intrepid Transcatheter Mitral Valve Replacement System in High Risk Patients with Severe, Symptomatic Mitral Regurgitation – The Twelve Intrepid TMVR Pilot Study; NCT02322840) 相似文献72.
73.
AB Majji M Ramappa SI Murthy PK Balne S Nalamada C Garudadri A Mathai U Gopinathan P Garg 《Ophthalmology》2012,119(9):1940-1941
74.
75.
Lennart van Gils Jochen Wöhrle David Hildick-Smith Sabine Bleiziffer Daniel J. Blackman Mohamed Abdel-Wahab Ulrich Gerckens Stephen Brecker Vinayak Bapat Thomas Modine Osama I. Soliman Andrey Nersesov Dominic Allocco Volkmar Falk Nicolas M. Van Mieghem 《JACC: Cardiovascular Interventions》2018,11(2):119-128
Objectives
The aim of this post hoc analysis from the RESPOND (Repositionable Lotus Valve System–Post-Market Evaluation of Real World Clinical Outcomes) post-market study was to assess the final implantation depth on the contrast aortogram after Lotus valve (Boston Scientific, Marlborough, Massachusetts) transcatheter aortic valve replacement (TAVR) and to correlate with permanent pacemaker implantation (PPI) and paravalvular leak (PVL).Background
Contrast aortography allows for the assessment of implantation depth and PVL during and after TAVR. Previous reports suggested an association between final device position and rates of PPI and PVL.Methods
The RESPOND study was a prospective, open-label, single-arm study in 41 centers evaluating outcomes after Lotus TAVR in routine clinical practice. Aortograms were collected at the Erasmus Medical Center and analyzed by researchers who were blinded to clinical outcomes. The primary analysis correlated implantation depth with PPI and PVL and required aortograms in a coaxial projection. The relation between implantation depth and need for PPI was assessed by multivariate logistic regression, adjusting for pre-defined confounders. A secondary analysis compared PVL analysis by contrast aortography with transthoracic echocardiography (TTE) performed by the independent core laboratory.Results
A total of 724 angiographic studies were included in this analysis. Mean Lotus implantation depth was 6.67 ± 2.19 mm. The overall PPI rate was 35%. PPI rate was lower with shallow implants (<6.5 mm: 21% vs. ≥6.5 mm: 41%; p < 0.001). After adjustment for confounders, implantation depth independently predicted need for PPI (odds ratio per 1-mm increment in depth: 1.200; 95% confidence interval: 1.091 to 1.319; p = 0.002). More than trivial PVL was present in 23% by contrast aortography and in 8% by TTE. Implantation depth was not correlated with PVL by contrast aortography or TTE (p = 0.342 and p = 0.149, respectively). PVL grading by contrast aortography and TTE was concordant in 77%.Conclusions
In this post hoc analysis of the RESPOND study PPI was highly correlated with implantation depth, whereas PVL was not. Higher Lotus implantation may reduce need for PPI. 相似文献76.
Immunosuppression and experimental amoebiasis in guinea-pigs 总被引:1,自引:0,他引:1
77.
Neil P. Fam Ralph Stephan von Bardeleben Mark Hensey Susheel K. Kodali Robert L. Smith Jörg Hausleiter Geraldine Ong Robert Boone Tobias Ruf Isaac George Molly Szerlip Michael Näbauer Faeez M. Ali Robert Moss Vinayak Bapat Katharina Schnitzler Felix Kreidel Jian Ye John G. Webb 《JACC: Cardiovascular Interventions》2021,14(5):501-511
ObjectivesThe purpose of this observational first-in-human experience was to investigate the feasibility and safety of the EVOQUE tricuspid valve replacement system and its impact on short-term clinical outcomes.BackgroundTranscatheter tricuspid intervention is a promising option for selected patients with severe tricuspid regurgitation (TR). Although transcatheter leaflet repair is an option for some, transcatheter tricuspid valve replacement (TTVR) may be applicable to a broader population.MethodsTwenty-five patients with severe TR underwent EVOQUE TTVR in a compassionate-use experience. The primary outcome was technical success, with NYHA (NYHA) functional class, TR grade, and major adverse cardiac and cerebrovascular events assessed at 30-day follow-up.ResultsAll patients (mean age 76 ± 3 years, 88% women) were at high surgical risk (mean Society of Thoracic Surgeons risk score 9.1 ± 2.3%), with 96% in NYHA functional class III or IV. TR etiology was predominantly functional, with mean tricuspid annular diameter of 44.8 ± 7.8 mm and mean tricuspid annular plane systolic excursion of 16 ± 2 mm. Technical success was 92%, with no intraprocedural mortality or conversion to surgery. At 30-day follow-up, mortality was 0%, 76% of patients were in NYHA functional class I or II, and TR grade was ≤2+ in 96%. Major bleeding occurred in 3 patients (12%), 2 patients (8%) required pacemaker implantation, and 1 patient (4%) required dialysis.ConclusionsThis first-in-human experience evaluating EVOQUE TTVR demonstrated high technical success, acceptable safety, and significant clinical improvement. Larger prospective studies are needed to confirm durability and safety and the impact on long-term clinical outcomes. 相似文献
78.
79.
Carolyn E. Come Alejandro A. Diaz Douglas Curran-Everett Nivedita Muralidhar Craig P. Hersh Jordan A. Zach Joyce Schroeder David A. Lynch Bartolome Celli George R. Washko 《Chest》2013,143(6):1607-1617
BackgroundCT scanning is increasingly used to characterize COPD. Although it is possible to obtain CT scan-measured lung lobe volumes, normal ranges remain unknown. Using COPDGene data, we developed reference equations for lobar volumes at maximal inflation (total lung capacity [TLC]) and relaxed exhalation (approximating functional residual capacity [FRC]).MethodsLinear regression was used to develop race-specific (non-Hispanic white [NHW], African American) reference equations for lobar volumes. Covariates included height and sex. Models were developed in a derivation cohort of 469 subjects with normal pulmonary function and validated in 546 similar subjects. These cohorts were combined to produce final prediction equations, which were applied to 2,191 subjects with old GOLD (Global Initiative for Chronic Obstructive Lung Disease) stage II to IV COPD.ResultsIn the derivation cohort, women had smaller lobar volumes than men. Height positively correlated with lobar volumes. Adjusting for height, NHWs had larger total lung and lobar volumes at TLC than African Americans; at FRC, NHWs only had larger lower lobes. Age and weight had no effect on lobar volumes at TLC but had small effects at FRC. In subjects with COPD at TLC, upper lobes exceeded 100% of predicted values in GOLD II disease; lower lobes were only inflated to this degree in subjects with GOLD IV disease. At FRC, gas trapping was severe irrespective of disease severity and appeared uniform across the lobes.ConclusionsReference equations for lobar volumes may be useful in assessing regional lung dysfunction and how it changes in response to pharmacologic therapies and surgical or endoscopic lung volume reduction. 相似文献
80.
Binding of hyperimmune serum opsonized merozoites of Plasmodium Yoelii nigerensis to trypsinized macrophages suggested it to be mediated by FcII receptor. Receptor blocking inhibition with monoclonal antibody 2.4G2 directed against Fc receptor for IgG1/IgG2b provided evidence that Fc delta 2b on macrophage played an important role in the merozoite-macrophage interactions. In addition, a neuraminidase sensitive receptor was noted to mediate the binding of P. yeelii merozoites in the absence of serum. Binding inhibition studies with two monosaccharides, D-mannose and alpha-methyl mannoside, indicated the role of Mannose/Fucose receptor on macrophage in this interaction. 相似文献