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Development of a wind gust model to estimate gust speeds and their return periods
Spatially dense observations of gust speeds are necessary for various applications, but their availability is limited in space and time. This work presents an approach to help to overcome this problem. The main objective is the generation of synthetic wind gust velocities. With this aim, theoretical wind and gust distributions are estimated from 10 yr of hourly observations collected at 123 synoptic weather stations provided by the German Weather Service. As pre-processing, an exposure correction is applied on measurements of the mean wind velocity to reduce the influence of local urban and topographic effects. The wind gust model is built as a transfer function between distribution parameters of wind and gust velocities. The aim of this procedure is to estimate the parameters of gusts at stations where only wind speed data is available. These parameters can be used to generate synthetic gusts, which can improve the accuracy of return periods at test sites with a lack of observations. The second objective is to determine return periods much longer than the nominal length of the original time series by considering extreme value statistics. Estimates for both local maximum return periods and average return periods for single historical events are provided. The comparison of maximum and average return periods shows that even storms with short average return periods may lead to local wind gusts with return periods of several decades. Despite uncertainties caused by the short length of the observational records, the method leads to consistent results, enabling a wide range of possible applications
CD44v/CD44s expression patterns are associated with the survival of pancreatic carcinoma patients
Molecular ecological chemistry in Arctic fjords at different stages of deglaciation (2016) - Cruise No. MSM56 – July 2 – July 25, 2016 – Longyearbyen (Norway) – Reykjavík (Iceland)
Physical oceanography during MARIA S. MERIAN cruise MSM56 (MECAF)
Data presented here were collected during the cruise MSM56 (Project MECAF) with the RV Maria S. Merian from Longyearbyen, Svalbard, Norway to Reykjavik, Iceland (July 01, 2016 to July 23, 2016). In total, 56 vertical CTD-hauls were conducted with the onboard CTD: in general, a deep cast up to bottom depth. The CTD system used was a Sea-Bird Electronics Inc. SBE 911plus, attached to a SBE 32 Carousel Water Sampler containing 24x 10-liter bottles. The system was equipped with: double temperature and conductivity probes, a pressure sensor (Digiquartz), an oxygen sensor (SBE 43), an altimeter (Benthos) and a chlorophyll fluorometer combined with a turbidity sensor (WET Labs ECO-AFL/FL). The sensors were pre-calibrated by the manufacturers for the ECO- AFL/FL additionally a post-cruise-calibration was done by the manufacturer. The data were recorded with the Seasave V 7.22 software and processed using SeaBird SBE Data Processing software. Data are visually checked. The ship position was derived from the shipboard GPS-system linked to the CTD data. The time zone is given in UTC. Salinity was quality checked by reference samples [n=20], measured with an Optimare Precision Salinometer (OPS S/N 003) 4 month after the cruise (S1: R² 0.9571)
PASCAL mitral valve repair system versus MitraClip: comparison of transcatheter edge-to-edge strategies in complex primary mitral regurgitation
Background!#!The PASCAL system is a novel device for edge-to-edge treatment of mitral regurgitation (MR). The aim of this study was to compare the safety and efficacy of the PASCAL to the MitraClip system in a highly selected group of patients with complex primary mitral regurgitation (PMR) defined as effective regurgitant orifice area (MR-EROA) ≥ 0.40 cm!##!Methods!#!38 patients with complex PMR undergoing mitral intervention using PASCAL (n = 22) or MitraClip (n = 16) were enrolled. Primary efficacy endpoints were procedural success and degree of residual MR at discharge. The rate of major adverse events (MAE) according to the Mitral Valve Academic Consortium (MVARC) criteria was chosen as the primary safety endpoint.!##!Results!#!Patient collectives did not differ relevantly regarding pertinent baseline parameters. Patients` median age was 83.0 [77.5-85.3] years (PASCAL) and 82.5 [76.5-86.5] years (MitraClip). MR-EROA at baseline was 0.70 [0.68-0.83] cm!##!Conclusion!#!In this highly selected patient group with complex PMR both systems exhibited equal procedural safety. MitraClip and PASCAL reduced qualitative and semi-quantitative parameters of MR to an at least comparable extent
Dynamics of Cognitive Function in Patients with Heart Failure Following Transcatheter Mitral Valve Repair
Aims: Interventional transcatheter edge-to-edge mitral valve repair (TMVR) is an established treatment option for patients with severe mitral regurgitation (MR) and high operative risk. Cognitive impairment is one of the most common conditions among often extensive comorbidities in these patients. The specific patterns of cognitive decline and particularly the effect of TMVR are not well described. Thus, this study aimed to investigate into the impact of TMVR on cognitive impairment, exercise capacity, and quality of life. Methods: Cognitive function (executive, naming, memory, attention, language, abstraction, and orientation) was assessed with the standardized Montreal Cognitive Assessment test (MoCA; range between 0 and 30 points) before and 3 months after TMVR in 72 consecutive patients alongside echocardiographic examination and assessment of exercise capacity (six-minute walk test) as well as quality-of-life questionnaires (Minnesota living with heart failure questionnaire, MLHF-Q). Results: Patients’ median age was 81 [76.0; 84.5] years, 39.7% were female with a median EuroScore II of 4.4% [2.9; 7.7]. The assessment of cognitive function showed a significant improvement of the cumulative MoCA-Test result (from 22.0 [19.0; 24.5] to 24 [22.0; 26.0]; p < 0.001) with significant changes in the subcategories executive (p < 0.001), attention (p < 0.001), abstraction (p < 0.001), and memory (p < 0.001). In addition, quality of life (from 47.5 [25.0; 69.3] to 24.0 [12.0; 40.0]; p < 0.001) and exercise capacity (from 220.0 m [160.0; 320.0] to 280.0 m [200.0; 380.0]; p = 0.003) increased significantly 3 months after the TMVR procedure. Conclusions: TMVR leads to a significant improvement of cognitive function, exercise capacity, and quality of life in patients with chronic heart failure in 3 months follow up and again highlights the benefit of the evermore established TMVR procedure for patients with high operative risk
Pre-Procedural Right Ventricular Longitudinal Strain and Post-Procedural Tricuspid Regurgitation Predict Mortality in Patients Undergoing Transcatheter Aortic Valve Implantation (TAVI)
Background: Right ventricular (RV) dysfunction has been linked to worse outcomes in patients undergoing TAVI. Assessment of RV function is challenging due to its complex morphology. RV longitudinal strain (LS) assessed by speckle-tracking echocardiography (STE) is a novel measure that may overcome most of the limitations of conventional echocardiographic parameters of RV function. The aim of current study was to assess the prognostic value of RV LS in patients undergoing TAVI and to assess echocardiographic predictors of long-term mortality. Methods and results: A retrospective analysis of all consecutive patients who underwent TAVI at our hospital between 1 January 2015 and 1 June 2016. Indication for TAVI was approved by a local heart-team. Echocardiographic data at baseline and after TAVI were re-analyzed and RV LS was measured in all patients with adequate image quality. A total of 229 patients were included in our study (mean age 83.8 ± 5 years, 62% women, mean EuroSCORE II 5.7 ± 5%). All-cause mortality occurred in 17.3% over a mean follow-up of 929 ± 373 days. In multivariate analysis, only baseline average RV free-wall LS (HR 1.05, 95% CI (1.01 to 1.10), p = 0.049) and more than mild tricuspid valve regurgitation (TR) after TAVI (HR 4.39, 95% CI (2.22 to 8.70), p < 0.001) independently increased the risk of all-cause mortality at long- term follow-up (2.5 years), while conventional echocardiographic parameters of RV function did not predict mortality. Conclusion: Pre-procedural RV LS and post-procedural tricuspid regurgitation significantly predicted long-term all-cause mortality in patients undergoing TAVI while conventional echocardiographic parameters of RV function failed in predicting long-term outcome. RV longitudinal strain by STE should be considered in the routine echocardiographic assessments of patients with severe AS
Transient acute right coronary artery deformation during transcatheter interventional tricuspid repair with the Cardioband tricuspid system
Background: The Cardioband tricuspid valve reconstruction system is a size-adjustable tricuspid reconstruction device for interventional treatment of tricuspid regurgitation (TR). Contraction of the device after successful implantation can be associated with an acute deformation of the right coronary artery (RCA). Aims: The aim of this study was to provide data on the persistence and clinical significance of acute RCA deformation following Cardioband implant procedures. Methods: Data from all patients with intraprocedural RCA deformation during Cardioband implantation were collected from four centres between October 2018 and January 2020. Control angiographies were performed in all of these patients before discharge. Results: RCA deformation occurred in 14 out of 51 patients. Follow-up coronary angiography showed a complete resolution of deformation in all cases while patients remained clinically asymptomatic and had an uneventful post-interventional course. Intraprocedural coronary stent implantation was performed in two of the earlier cases according to the personal assessment of the implanters. Conclusions: RCA deformation is relatively frequent following interventional tricuspid annuloplasty but appears to be completely reversible in the absence of flow impairment or vascular damage. Based on our early experience watchful waiting is the most appropriate strategy to avoid unnecessary coronary interventions
Transcatheter Treatment of Secondary Tricuspid Regurgitation With Direct Annuloplasty Results From a Multicenter Real-World Experience
Background: Treatment options for secondary tricuspid regurgitation (TR) remain limited. Early real-world data of a new percutaneous direct annuloplasty system for tricuspid repair were examined. Methods: The first 60 patients treated with the Cardioband tricuspid valve repair system at 4 centers were included in this retrospective study. The primary efficacy end point was technical success with reduction of TR >= 2 grades at discharge. Combined primary safety end point was major adverse events (death, myocardial infarction, cardiothoracic surgery, and stroke) at 30 days. Results: Median patient age was 76 years (73-82), median EuroScore II was 3.9% (2.2-8.1), heart failure with preserved ejection fraction was present in 78%, and 81.7% were in the New York Heart Association class III/IV. Massive or torrential TR was found in 51.7%, and severe TR in 48.3%. The primary efficacy end point was achieved in 45%, while 60.3% of patients had less-than-severe TR at discharge. Vena contracta was reduced by 47% from 12.9 +/- 4.8 to 7.0 +/- 3.4 mm (P<0.001). Overall, the majority of patients (81.7%) improved at least by 1 New York Heart Association class. At follow-up 81.3% of patients presented in the New York Heart Association class I or II. The primary safety end point occurred in 4 patients with 2 in-hospital deaths, both not device related. Right coronary artery complications (vessel perforation or stent implantation) occurred in 9 patients (15%). Procedural time decreased from 298 to 185 minutes (P<0.001) with efficacy remaining stable (P=0.817) when comparing procedure numbers 11 or more to the earliest 5 procedures per center. Conclusions: This first real-world experience suggests that transcatheter treatment of advanced secondary TR using direct annuloplasty is feasible and reasonably safe early in the learning curve, with significant symptomatic benefit. Further studies are warranted to provide data on long-term outcome and patient prognosis
Transcatheter valve repair of tricuspid regurgitation with the PASCAL system: TriCLASP study 30-day results
Background Severe tricuspid regurgitation (TR) is independently associated with increased morbidity and mortality. Percutaneous transcatheter approaches may offer an alternative for patients not amenable to surgery. Methods TriCLASP is a prospective, single-arm, multicenter European post-market clinical follow-up study (NCT04614402) to evaluate the safety and performance of the PASCAL system (Edwards Lifesciences) in patients with severe or greater TR. At 30 days, a composite of major adverse events (MAEs) adjudicated by a clinical events committee, echocardiographic parameters adjudicated by core laboratory, and clinical, functional, and quality-of-life measures were evaluated. Results Mean age of the 74 enrolled patients was 80.3 years, with 58.1% female, 90.5% systemic hypertension, and 77.0% in New York Heart Association (NYHA) class III/IV. Mean Society for Thoracic Surgeons score (MV repair) was 9.0%. TR severity was significantly reduced at discharge (p < 0.001) and sustained at 30 days (p < 0.001), and 90.0% of patients achieved <= moderate TR. The composite MAE rate at 30 days was 3.0%, including 4 events in 2 patients: cardiovascular mortality 1.5%, stroke 1.5%, renal complications requiring unplanned dialysis or renal replacement therapy 1.5%, and severe bleeding 1.5%. There were no nonelective tricuspid valve reinterventions, major access site and vascular complications, major cardiac structural complications, or device embolizations. NYHA class I/II was achieved in 55.8%, 6-minute walk distance improved by 38.2 m (p < 0.001), and Kansas City cardiomyopathy questionnaire scores improved by 13.4 points (p < 0.001). Conclusion Experience with the PASCAL transcatheter valve repair system in a European post-market setting confirms favorable safety and effectiveness at 30 days. TR significantly reduced, and clinical, functional, and quality-of-life outcomes significantly improved. This study is ongoing. Clinical Trial Registration: The study is ongoing and registered on as NCT04614402. The current analysis is an interim report