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1.
Environ Toxicol Chem ; 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31233239

RESUMO

Activated carbon-amended bed sediments reduced total polychlorinated biphenyl (PCB) accumulation in 3 functionally different marine species, sandworms (Alitta virens), hard clams (Mercenaria mercenaria), and sheepshead minnows (Cyprinodon variegatus), during both clean and contaminated ongoing sediment inputs. Mesocosm experiments were conducted for 90 d to evaluate native, field-aged bed sediment PCBs, and ongoing input PCBs added 3 times a week. Simulated in situ remediation applied an activated carbon dose equal to the native organic carbon content that was premixed into the bed sediment for 1 mo. The highest bioaccumulation of native PCBs was in worms that remained in and directly ingested the sediment, whereas the highest bioaccumulation of the input PCBs was in fish that were exposed to the water column. When periodic PCB-contaminated sediment inputs were introduced to the water column, the activated carbon remedy had minimal effect on the input PCBs, whereas the native bed PCBs still dominated bioaccumulation in the control (no activated carbon). Therefore, remediation of only the local bedded sediment in environmental systems with ongoing contaminant inputs may have lower efficacy for fish and other pelagic and epibenthic organisms. While ongoing inputs continue to obscure remedial outcomes at contaminated sediment sites, the present study showed clear effectiveness of activated carbon amendment remediation on native PCBs despite these inputs but no remediation effectiveness for the input-associated PCBs (at least within the present study duration). Environ Toxicol Chem 2019:1-11. Published 2019 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

3.
N Engl J Med ; 380(26): 2541-2550, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-30946551

RESUMO

BACKGROUND: During the introduction of transcatheter aortic-valve replacement (TAVR) in the United States, requirements regarding procedural volume were mandated by the Centers for Medicare and Medicaid Services as a condition of reimbursement. A better understanding of the relationship between hospital volume of TAVR procedures and patient outcomes could inform policy decisions. METHODS: We analyzed data from the Transcatheter Valve Therapy Registry regarding procedural volumes and outcomes from 2015 through 2017. The primary analyses examined the association between hospital procedural volume as a continuous variable and risk-adjusted mortality at 30 days after transfemoral TAVR. Secondary analysis included risk-adjusted mortality according to quartile of hospital procedural volume. A sensitivity analysis was performed after exclusion of the first 12 months of transfemoral TAVR procedures at each hospital. RESULTS: Of 113,662 TAVR procedures performed at 555 hospitals by 2960 operators, 96,256 (84.7%) involved a transfemoral approach. There was a significant inverse association between annualized volume of transfemoral TAVR procedures and mortality. Adjusted 30-day mortality was higher and more variable at hospitals in the lowest-volume quartile (3.19%; 95% confidence interval [CI], 2.78 to 3.67) than at hospitals in the highest-volume quartile (2.66%; 95% CI, 2.48 to 2.85) (odds ratio, 1.21; P = 0.02). The difference in adjusted mortality between a mean annualized volume of 27 procedures in the lowest-volume quartile and 143 procedures in the highest-volume quartile was a relative reduction of 19.45% (95% CI, 8.63 to 30.26). After the exclusion of the first 12 months of TAVR procedures at each hospital, 30-day mortality remained higher in the lowest-volume quartile than in the highest-volume quartile (3.10% vs. 2.61%; odds ratio, 1.19; 95% CI, 1.01 to 1.40). CONCLUSIONS: An inverse volume-mortality association was observed for transfemoral TAVR procedures from 2015 through 2017. Mortality at 30 days was higher and more variable at hospitals with a low procedural volume than at hospitals with a high procedural volume. (Funded by the American College of Cardiology Foundation National Cardiovascular Data Registry and the Society of Thoracic Surgeons.).


Assuntos
Estenose da Valva Aórtica/cirurgia , Hospitais com Alto Volume de Atendimentos/estatística & dados numéricos , Hospitais com Baixo Volume de Atendimentos/estatística & dados numéricos , Substituição da Valva Aórtica Transcateter/mortalidade , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Centers for Medicare and Medicaid Services (U.S.) , Feminino , Mortalidade Hospitalar , Humanos , Reembolso de Seguro de Saúde/normas , Masculino , Estudos Retrospectivos , Substituição da Valva Aórtica Transcateter/métodos , Substituição da Valva Aórtica Transcateter/estatística & dados numéricos , Resultado do Tratamento , Estados Unidos/epidemiologia
6.
JACC Cardiovasc Interv ; 11(12): 1201-1203, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29860073
9.
Catheter Cardiovasc Interv ; 92(4): 757-765, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29171682

RESUMO

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is an alternative to surgical aortic valve replacement (SAVR) for patients with severe symptomatic aortic stenosis (AS) who are at intermediate and high risk for surgery. Commercial use of TAVR has expanded to patients with end stage renal disease (ESRD). OBJECTIVES: Compare in-hospital outcomes of TAVR versus SAVR in ESRD patients requiring hemodialysis (HD). METHODS: ESRD patients on HD undergoing TAVR (n = 328) or SAVR (n = 697) between 2012 and 2014 were identified in the National Inpatient Sample (NIS). Propensity-score matching method was used to minimize selection bias. Baseline characteristics and in-hospital outcomes were compared. RESULTS: TAVR patients were older (75.3 vs. 61.6 years, P < 0.001) and had more comorbidities, including congestive heart failure (16.2% vs. 7.5%), diabetes mellitus (28.4% vs. 22.5%), chronic lung disease (27.7% vs. 20.4%), and peripheral vascular disease (35.1% vs. 21.2%). Propensity-score matching yielded 175 pairs of patients matched on 30 baseline covariates. Overall in-hospital mortality was high (9.9%) and similar between TAVR and SAVR (8% vs. 10.3%, P = 0.58). TAVR was associated with shorter length of stay (LOS) (8 vs. 14 days, P < 0.001), lower hospitalization cost ($276,448 vs. $364,280, P = 0.01), lower in-hospital complications (60.6% vs. 76%, P = 0.003), and higher rate of home discharge (31.4% vs. 17.7%, P = 0.004) compared with SAVR. CONCLUSIONS: Regardless of treatment modality, patients with AS on HD have high in-hospital mortality. TAVR and SAVR have comparable in-hospital mortality in this population. However, TAVR is associated with shorter LOS, lower hospitalization costs, lower in-hospital complications, and higher rates of home discharge.

10.
Eur Heart J ; 39(15): 1224-1245, 2018 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28430909

RESUMO

The VARC (Valve Academic Research Consortium) for transcatheter aortic valve replacement set the standard for selecting appropriate clinical endpoints reflecting safety and effectiveness of transcatheter devices, and defining single and composite clinical endpoints for clinical trials. No such standardization exists for circumferentially sutured surgical valve paravalvular leak (PVL) closure. This document seeks to provide core principles, appropriate clinical endpoints, and endpoint definitions to be used in clinical trials of PVL closure devices. The PVL Academic Research Consortium met to review evidence and make recommendations for assessment of disease severity, data collection, and updated endpoint definitions. A 5-class grading scheme to evaluate PVL was developed in concordance with VARC recommendations. Unresolved issues in the field are outlined. The current PVL Academic Research Consortium provides recommendations for assessment of disease severity, data collection, and endpoint definitions. Future research in the field is warranted.

11.
J Am Soc Echocardiogr ; 31(2): 117-147, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29254695

RESUMO

The American College of Cardiology collaborated with the American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, European Association for Cardio-Thoracic Surgery, Heart Valve Society, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons to develop and evaluate Appropriate Use Criteria (AUC) for the treatment of patients with severe aortic stenosis (AS). This is the first AUC to address the topic of AS and its treatment options, including surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR). A number of common patient scenarios experienced in daily practice were developed along with assumptions and definitions for those scenarios, which were all created using guidelines, clinical trial data, and expert opinion in the field of AS. The 2014 AHA/ACC guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines(1) and its 2017 focused update paper (2) were used as the primary guiding references in developing these indications. The writing group identified 95 clinical scenarios based on patient symptoms and clinical presentation, and up to 6 potential treatment options for those patients. A separate, independent rating panel was asked to score each indication from 1 to 9, with 1-3 categorized as "Rarely Appropriate," 4-6 as "May Be Appropriate," and 7-9 as "Appropriate." After considering factors such as symptom status, left ventricular (LV) function, surgical risk, and the presence of concomitant coronary or other valve disease, the rating panel determined that either SAVR or TAVR is Appropriate in most patients with symptomatic AS at intermediate or high surgical risk; however, situations commonly arise in clinical practice in which the indications for SAVR or TAVR are less clear, including situations in which 1 form of valve replacement would appear reasonable when the other is less so, as do other circumstances in which neither intervention is the suitable treatment option. The purpose of this AUC is to provide guidance to clinicians in the care of patients with severe AS by identifying the reasonable treatment and intervention options available based on the myriad clinical scenarios with which patients present. This AUC document also serves as an educational and quality improvement tool to identify patterns of care and reduce the number of rarely appropriate interventions in clinical practice.

13.
J Am Coll Cardiol ; 69(16): 2067-2087, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28427582

RESUMO

The VARC (Valve Academic Research Consortium) for transcatheter aortic valve replacement set the standard for selecting appropriate clinical endpoints reflecting safety and effectiveness of transcatheter devices, and defining single and composite clinical endpoints for clinical trials. No such standardization exists for circumferentially sutured surgical valve paravalvular leak (PVL) closure. This document seeks to provide core principles, appropriate clinical endpoints, and endpoint definitions to be used in clinical trials of PVL closure devices. The PVL Academic Research Consortium met to review evidence and make recommendations for assessment of disease severity, data collection, and updated endpoint definitions. A 5-class grading scheme to evaluate PVL was developed in concordance with VARC recommendations. Unresolved issues in the field are outlined. The current PVL Academic Research Consortium provides recommendations for assessment of disease severity, data collection, and endpoint definitions. Future research in the field is warranted.


Assuntos
Valva Aórtica , Próteses Valvulares Cardíacas/efeitos adversos , Avaliação de Resultados (Cuidados de Saúde)/métodos , Substituição da Valva Aórtica Transcateter , Ensaios Clínicos como Assunto , Ecocardiografia , Humanos , Projetos de Pesquisa , Medição de Risco
14.
JACC Cardiovasc Imaging ; 10(4): 461-470, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28385256

RESUMO

Subclinical leaflet thrombosis was recently described in a randomized trial of transcatheter aortic valve replacement. It was subsequently demonstrated in a series of registries that this was a commonly observed imaging finding seen in all transcatheter and surgical bioprostheses. The phenomenon has aroused considerable interest due to the as-yet-undefined risk for later clinical events and the possibility of pharmacological intervention with anticoagulation. Subclinical leaflet thrombosis is easily detected noninvasively by technically suitable computed tomography (CT) with a high degree of concordance to transesophageal echocardiography findings. The CT hallmarks were noted to be hypoattenuated leaflet thickening (HALT) associated with reduced leaflet motion (RELM). The combination of HALT and RELM signified hypoattenuation affecting motion, the standardized imaging endpoint used. This paper describes the systematic CT evaluation methodology that was devised during the Portico trial investigation and U.S. Food and Drug Administration submission; it also highlights the need for an ongoing discussion among experts to enable, with the help of the Valve Academic Research Consortium, standardization of reporting of this imaging finding to cater to the present and future needs of clinical trials.


Assuntos
Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Valva Aórtica/fisiopatologia , Doenças Assintomáticas , Bioprótese , Ecocardiografia Transesofagiana , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/instrumentação , Humanos , Valor Preditivo dos Testes , Fatores de Risco , Índice de Gravidade de Doença , Trombose/etiologia , Trombose/terapia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/instrumentação , Resultado do Tratamento
15.
Catheter Cardiovasc Interv ; 89(5): 944-950, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28168809

RESUMO

OBJECTIVES: To describe the feasibility and safety of the Hopscotch Technique, a novel method to close paravalvular leaks. BACKGROUND: Successful closure of paravalvular leaks requires the complete seal of irregular defects, frequently interrupted by remaining sutures or tissue that converts a large defect into a complex series of contiguous smaller defects. Successful treatment with devices placed in a single space is impossible with constrained appearance and significant residual leak; therefore, new techniques to deploy smaller devices in the correct location are needed. METHODS: We retrospective analyzed all the patients with mitral PVLs undergoing percutaneous closure with the Hopscotch technique from November 2011 to January 2016. RESULTS: Sixteen procedures were performed in 15 patients (median age 66-year-old, 67% male, STS 3.9%), most of them with biological prostheses (73%). Mean PVL size was 12.5 mm located in the lateral position. Percutaneous transapical access was the final approach in nine procedures and success of the procedure was achieved in 12. Usually, the technique was performed by 1 Hopscotch crossing/jump; however, complex procedures requiring 2 or 3 crossings were utilized in 4 patients, even possible between aortic and mitral leaks along the aortic-mitral continuity. Residual mitral paravalvular regurgitation of ≤mild was achieved in 93% of procedures. CONCLUSIONS: The Hopscotch technique is feasible and safety for patients with mitral paravalvular leak when boundaries prevent full device expansion. © 2017 Wiley Periodicals, Inc.


Assuntos
Cateterismo Cardíaco/métodos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Idoso , Ecocardiografia Doppler em Cores , Ecocardiografia Tridimensional , Ecocardiografia Transesofagiana , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/diagnóstico , Falha de Prótese , Reoperação , Estudos Retrospectivos
16.
J Biomech ; 53: 15-21, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-28139202

RESUMO

The analysis is based on a finite element procedure to extract the contact forces between an implanted Nitinol stent and the surrounding host tissue using postoperative CT images. The methodology was applied for patients (N=46) which have undergone a TAVI procedure with the Medtronic CoreValve Revalving System (MCRS) to obtain corresponding deformation and force maps. The postoperative CT data were recorded for each patient in both systolic and diastolic phase of the heart cycle. Scalar parameters were defined, which map deformed geometry and contact force field to mechanically relevant quantities: radial dilatation, radial shape distortion, non-convex points, mean force, a force deviation measure and a pressure equivalent. The latter demonstrates that in the area of the aortic root, the added circumferential loading is of the same order as the baseline average blood pressure, thus leading to a doubling of the local mechanical load. Generally the force distribution along the stent is non-homogeneous. A comparison of systolic and diastolic data revealed slightly higher contact forces during the diastole, indicating that the stent has to carry more load in this phase. The geometrical and mechanical parameters were compared for two types of clinical complication: para-valvular leakage (PVL) and permanent pacemaker requirement (PPM). It was found that an increase in mean force can be associated with both complications; significantly for PVL and as a trend for PPM.


Assuntos
Valva Aórtica/fisiologia , Stents , Substituição da Valva Aórtica Transcateter , Ligas , Valva Aórtica/cirurgia , Diástole , Análise de Elementos Finitos , Humanos , Período Pós-Operatório , Sístole
19.
Ann Thorac Surg ; 103(3): 1021-1035, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27955994

RESUMO

BACKGROUND: The Society of Thoracic Surgeons (STS)/American College of Cardiology Transcatheter Valve Therapy (TVT) Registry captures all procedures with Food and Drug Administration-approved transcatheter valve devices performed in the United States, and is mandated as a condition of reimbursement by the Centers for Medicaid & Medicare Services. OBJECTIVES: This annual report focuses on patient characteristics, trends, and outcomes of transcatheter aortic and mitral valve catheter-based valve procedures in the United States. METHODS: We reviewed data for all patients receiving commercially approved devices from 2012 through December 31, 2015, that are entered in the TVT Registry. RESULTS: The 54,782 patients with transcatheter aortic valve replacement demonstrated decreases in expected risk of 30-day operative mortality (STS Predicted Risk of Mortality [PROM]) of 7% to 6% and transcatheter aortic valve replacement PROM (TVT PROM) of 4% to 3% (both p < 0.0001) from 2012 to 2015. Observed in-hospital mortality decreased from 5.7% to 2.9%, and 1-year mortality decreased from 25.8% to 21.6%. However, 30-day post-procedure pacemaker insertion increased from 8.8% in 2013 to 12.0% in 2015. The 2,556 patients who underwent transcatheter mitral leaflet clip in 2015 were similar to patients from 2013 to 2014, with hospital mortality of 2% and with mitral regurgitation reduced to grade ≤2 in 87% of patients (p < 0.0001). The 349 patients who underwent mitral valve-in-valve and mitral valve-in-ring procedures were high risk, with an STS PROM for mitral valve replacement of 11%. The observed hospital mortality was 7.2%, and 30-day post-procedure mortality was 8.5%. CONCLUSIONS: The TVT Registry is an innovative registry that that monitors quality, patient safety and trends for these rapidly evolving new technologies.


Assuntos
Estenose da Valva Aórtica/cirurgia , Estenose da Valva Mitral/cirurgia , Sistema de Registros , Substituição da Valva Aórtica Transcateter/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/diagnóstico , Estenose da Valva Mitral/mortalidade , Estudos Retrospectivos , Sociedades Médicas , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade , Resultado do Tratamento , Estados Unidos
20.
J Am Coll Cardiol ; 69(10): 1215-1230, 2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-27956264

RESUMO

BACKGROUND: The Society of Thoracic Surgeons (STS)/American College of Cardiology Transcatheter Valve Therapy (TVT) Registry captures all procedures with Food and Drug Administration-approved transcatheter valve devices performed in the United States, and is mandated as a condition of reimbursement by the Centers for Medicaid & Medicare Services. OBJECTIVES: This annual report focuses on patient characteristics, trends, and outcomes of transcatheter aortic and mitral valve catheter-based valve procedures in the United States. METHODS: We reviewed data for all patients receiving commercially approved devices from 2012 through December 31, 2015, that are entered in the TVT Registry. RESULTS: The 54,782 patients with transcatheter aortic valve replacement demonstrated decreases in expected risk of 30-day operative mortality (STS Predicted Risk of Mortality [PROM]) of 7% to 6% and transcatheter aortic valve replacement PROM (TVT PROM) of 4% to 3% (both p < 0.0001) from 2012 to 2015. Observed in-hospital mortality decreased from 5.7% to 2.9%, and 1-year mortality decreased from 25.8% to 21.6%. However, 30-day post-procedure pacemaker insertion increased from 8.8% in 2013 to 12.0% in 2015. The 2,556 patients who underwent transcatheter mitral leaflet clip in 2015 were similar to patients from 2013 to 2014, with hospital mortality of 2% and with mitral regurgitation reduced to grade ≤2 in 87% of patients (p < 0.0001). The 349 patients who underwent mitral valve-in-valve and mitral valve-in-ring procedures were high risk, with an STS PROM for mitral valve replacement of 11%. The observed hospital mortality was 7.2%, and 30-day post-procedure mortality was 8.5%. CONCLUSIONS: The TVT Registry is an innovative registry that that monitors quality, patient safety and trends for these rapidly evolving new technologies.


Assuntos
Cateterismo Cardíaco , Cardiologia , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/estatística & dados numéricos , Sistema de Registros , Sociedades Médicas , Cirurgia Torácica , Congressos como Assunto , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Estados Unidos
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