PLASMA DEVICE

DOEpatents

Baker, W.R.; Brathenahl, A.; Furth, H.P.

1962-04-10

A device for producing a confined high temperature plasma is described. In the device the concave inner surface of an outer annular electrode is disposed concentrically about and facing the convex outer face of an inner annular electrode across which electrodes a high potential is applied to produce an electric field there between. Means is provided to create a magnetic field perpendicular to the electric field and a gas is supplied at reduced pressure in the area therebetween. Upon application of the high potential, the gas between the electrodes is ionized, heated, and under the influence of the electric and magnetic fields there is produced a rotating annular plasma disk. The ionized plasma has high dielectric constant properties. The device is useful as a fast discharge rate capacitor, in controlled thermonuclear research, and other high temperature gas applications. (AEC)

Micro-Fresnel Zone Plate Optical Devices Using Densely Accumulated Ray Points

NASA Technical Reports Server (NTRS)

Choi, Sang H. (Inventor); Park, Yeonjoon (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor)

2011-01-01

An embodiment generally relates to an optical device suitable for use with an optical medium for the storage and retrieval of data. The optical device includes an illumination means for providing a beam of optical radiation of wavelength .lamda. and an optical path that the beam of optical radiation follows. The optical device also includes a diffractive optical element defined by a plurality of annular sections. The plurality of annular sections having a first material alternately disposed with a plurality of annular sections comprising a second material. The diffractive optical element generates a plurality of focal points and densely accumulated ray points with phase contrast phenomena and the optical medium is positioned at a selected focal point or ray point of the diffractive optical element.

Leaflet area as a determinant of tricuspid regurgitation severity in patients with pulmonary hypertension.

PubMed

Afilalo, Jonathan; Grapsa, Julia; Nihoyannopoulos, Petros; Beaudoin, Jonathan; Gibbs, J Simon R; Channick, Richard N; Langleben, David; Rudski, Lawrence G; Hua, Lanqi; Handschumacher, Mark D; Picard, Michael H; Levine, Robert A

2015-05-01

Tricuspid regurgitation (TR) is a risk factor for mortality in pulmonary hypertension (PH). TR severity varies among patients with comparable degrees of PH and right ventricular remodeling. The contribution of leaflet adaptation to the pathophysiology of TR has yet to be examined. We hypothesized that tricuspid leaflet area (TLA) is increased in PH, and that the adequacy of this increase relative to right ventricular remodeling determines TR severity. A prospective cohort of 255 patients with PH from pre and postcapillary pathogeneses was assembled from 2 centers. Patients underwent a 3-dimensional echocardiogram focused on the tricuspid apparatus. TLA was measured with the Omni 4D software package. Compared with normal controls, patients with PH had a 2-fold increase in right ventricular volumes, 62% increase in annular area, and 49% increase in TLA. Those with severe TR demonstrated inadequate increase in TLA relative to the closure area, such that the ratio of TLA:closure area <1.78 was highly predictive of severe TR (odds ratio, 68.7; 95% confidence interval, 16.2-292.7). The median vena contracta width was 8.5 mm in the group with small TLA and large closure area as opposed to 4.8 mm in the group with large TLA and large closure area. TLA plays a significant role in determining which patients with PH develop severe functional TR. The ratio of TLA:closure area, reflecting the balance between leaflet adaptation versus annular dilation and tethering forces, is an indicator of TR severity that may identify which patients stand to benefit from leaflet augmentation during tricuspid valve repair. © 2015 American Heart Association, Inc.

Electron beam diagnostic system using computed tomography and an annular sensor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elmer, John W.; Teruya, Alan T.

2015-08-11

A system for analyzing an electron beam including a circular electron beam diagnostic sensor adapted to receive the electron beam, the circular electron beam diagnostic sensor having a central axis; an annular sensor structure operatively connected to the circular electron beam diagnostic sensor, wherein the sensor structure receives the electron beam; a system for sweeping the electron beam radially outward from the central axis of the circular electron beam diagnostic sensor to the annular sensor structure wherein the electron beam is intercepted by the annular sensor structure; and a device for measuring the electron beam that is intercepted by themore » annular sensor structure.« less

Electron beam diagnostic system using computed tomography and an annular sensor

DOEpatents

Elmer, John W.; Teruya, Alan T.

2014-07-29

A system for analyzing an electron beam including a circular electron beam diagnostic sensor adapted to receive the electron beam, the circular electron beam diagnostic sensor having a central axis; an annular sensor structure operatively connected to the circular electron beam diagnostic sensor, wherein the sensor structure receives the electron beam; a system for sweeping the electron beam radially outward from the central axis of the circular electron beam diagnostic sensor to the annular sensor structure wherein the electron beam is intercepted by the annular sensor structure; and a device for measuring the electron beam that is intercepted by the annular sensor structure.

Lens fiber organization in four avian species: a scanning electron microscopic study.

PubMed

Willekens, B; Vrensen, G

1985-01-01

The three-dimensional organization of the eye lenses of the chicken, the canary, the song-thrush and the kestrel was studied using light and scanning electron microscopy. The lenses of birds are characterized by the presence of two distinct compartments: the annular pad and the main lens body, separated by a cavum lenticuli. The annular pad fibers had a hexagonal circumference all contained a round nucleus and except for the canary were smooth-surfaced and lacking anchoring devices. In the canary, however, the annular pad fibers were studded with edge protrusions and ball-and-socket junctions. The semicircular main lens body fibers of all four species were studded with ball-and-socket junctions and edge protrusions. In contrast with mammals these anchoring devices were present throughout the lens up to the embryonal nucleus. Superficially the main lens body fibers were extremely flat. Additionally membrane elevations and depressions and globular elements were found on these central fibers in three species, the kestrel being the exception. At the transition between annular pad and main lens body the fibers turned their course and the nuclei became oval and disappeared in the deeper aspect of the main lens body. The cavum lenticuli was filled with globules tied off from the annular pad fibers. It seems attractive to assume that the presence of a separated annular pad, a cavum lenticuli filled with globular elements, the extreme flatness of the superficial central fibers and the studding of these central fibers with anchoring devices up to the embryonal nucleus are morphological expressions of the mouldability of the bird's eye lenses and consequently would explain their efficient accommodative mechanism including formation of a lenticonus. The presence of nuclei in the annular pad fibers and their typical change at the transitional zone between annular pad and main lens body are suggestive for a two-phased differentiation in bird's lens fibers: differentiation of the germinative epithelial cells to annular pad fibers which migrate to the main lens body after which they differentiate further to main lens body fibers.

Port closure techniques.

PubMed

Shaher, Z

2007-08-01

Laparoscopic trocars do create wounds. This article aims to review and list different techniques used for closure of the fascia incision at trocar sites. A literature search was performed for articles dealing with closure techniques. The author searched this subject in English on Medline by combining the words "trocar" and "hernia," as well as "Deschamps" and "Reverdin." All articles reporting techniques with their references were reviewed. The articles described many techniques in addition to classical closure using curved needles, including Grice needle, Maciol needles, Endoclose device, Carter-Thomason device, Tahoe ligature device, Endo-Judge device, eXit puncture closure device, Lowsley retractor, spinal cord needles, dual hemostat, suture carrier, Riverdin and Deschamps needles, and Gore-Tex closure device. Three main groups of techniques were found with favor of extracorporeal manipulations under direct visualization. Old methods are sufficient and cost-effective.

Annular Momentum Control Device (AMCD). Volume 1: Laboratory model development

NASA Technical Reports Server (NTRS)

1975-01-01

The annular momentum control device (AMCD) a thin hoop-like wheel with neither shaft nor spokes is described. The wheel floats in a magnetic field and can be rotated by a segmented motor. Potential advantages of such a wheel are low weight, configuration flexibility, a wheel that stiffens with increased speed, vibration isolation, and increased reliability. The analysis, design, fabrication, and testing is described of the laboratory model of the AMCD.

Comparison of cost-effectiveness and postoperative outcome of device closure and open surgery closure techniques for treatment of patent ductus arteriosus.

PubMed

Ahmadi, Alireza; Sabri, Mohammadreza; Bigdelian, Hamid; Dehghan, Bahar; Gharipour, Mojgan

2014-01-01

Various devices have been recently employed for percutaneous closure of the patent ductus arteriosus (PDA). Although the high effectiveness of device closure techniques has been clearly determined, a few studies have focused on the cost-effectiveness and also postoperative complications of these procedures in comparison with open surgery. The present study aimed to evaluate the clinical outcome and cost-effectiveness of PDA occlusion by Amplatzer and coil device in comparisong with open surgery. In this cross-sectional study, a randomized sample of 201 patients aged 1 month to 16 years (105 patients with device closure and 96 patients with surgical closure) was selected. The ratio of total pulmonary blood flow to total systemic blood flow, the Qp/Qs ratio, was measured using a pulmonary artery catheter. The cost analysis included direct medical care costs associated with device implantation and open surgery, as well as professional fees. All costs were calculated in Iranian Rials and then converted to US dollars. There was no statistical difference in mean Qp/Qs ratio before the procedure between the device closure group and the open surgery group (2.1 ± 0.7 versus 1.7 ± 0.6, P = 0.090). The mean measured costs were overall higher in the device closure group than in open closure group (948.87 ± 548.76 US$ versus 743.70 ± 696.91 US$, P < 0.001). This difference remained significant after adjustment for age and gender (Standardized Beta = 0.160, P = 0.031). PDA closure with the Amplatzer ductal occluder (1053.05 ± 525.73 US$) or with Nit-Occlud coils (PFM) (912.73 ± 565.94 US$, P < 0.001) was more expensive than that via open surgery. However, the Cook detachable spring coils device closure (605.65 ± 194.62 US$, P = 0.650) had a non-significant cost difference with open surgery. No event was observed in the device closure group regarding in-hospital mortality or morbidity; however, in another group, 2 in-hospital deaths occurred, two patients experienced pneumonia and seizure, and one suffered electrolyte abnormalities including hyponatremia and hypocalcemia. Although open surgery seems to be less expensive than device closure technique, because of lower mortality and morbidity, the latter group is more preferable.

Comparison of V-Loc™ 180 wound closure device and Quill™ PDO knotless tissue-closure device for intradermal closure in a porcine in vivo model: evaluation of biomechanical wound strength.

PubMed

Gingras, Kristen; Zaruby, Jeffrey; Maul, Don

2012-05-01

The objective of this study was to compare the biomechanical strength of two barbed suture devices: V-Loc™ 180 Wound Closure Device and Quill™ PDO Knotless Tissue-Closure Device following primary cosmetic skin closures in a porcine dermal model. This prospective randomized, controlled in vivo trial compared size 3/0 V-Loc™ 180 device to size 2/0 Quill™ PDO device. Both products were tested for dermal closure in adult porcine models and evaluated at five timepoints. At postoperative days 0, 3, 7, 14, and 28 sutured tissue regions were excised post mortem and tested for intradermal wound holding strength. Wounds closed with V-Loc™ 180 device were stronger than Quill™ PDO device at days 0, 3, 7, and 14 with these differences being significant (p < 0.05) at days 3 and 7. At day 3, the average maximum load of V-Loc™ 180 was 13.53 kgf and Quill™ PDO was 10.38 kgf (p = 0.002). At day 7, the average maximum load of V-Loc™ 180 was 10.4 kgf and Quill™ PDO was 7.56 kgf (p = 0.001). Throughout the duration of the study, there was no suture extrusion or tissue distortion and all wounds healed with no major complications. In this study, V-Loc™ 180 device was significantly stronger than Quill™ PDO device during the critical phases of wound healing in skin. Copyright © 2012 Wiley Periodicals, Inc.

Percutaneous device closure of patent ductus arteriosus with pulmonary artery hypertension: long-term results.

PubMed

Vijayalakshmi, Ishwarappa Balekundri; Setty, Natraj; Narasimhan, Chitra; Singla, Vivek; Manjunath, Cholenahalli Nanjappa

2014-12-01

Device closure of patent ductus arteriosus (PDA) is treatment of choice. But device closure in presence of pulmonary artery hypertension (PAH) remains a challenge. Data on patient selection, technical considerations, and complications are limited. To know the challenges and efficacy of device closure of PDA with PAH. Out of 1,325 cases of device closure of PDA, 246 (18.6%) with PAH formed the study material. To test the feasibility, chosen device is used to occlude PDA for ten minutes without oxygen inhalation. The device is released only if PAH reduced. PAH decreased in all except in 1 patient after closure with muscular ventricular septal occluder (MVSDO), pulmonary artery pressure (PAP) transiently increased (became supra-systemic), without significant reduction in aortic pressure. Device embolized in 8 patients (3.3%). Percutaneous retrieval was done in 4 (by snare in 2 and by fixing the cable to device in 2) and replaced with bigger devices. The surgical removal of the embolized MVSDO and ligation was done in 4 cases. All patients were on oral sildenafil and bosentan until PAP regressed to normal. Follow up was from 6 months to 9 years. No residual shunt in any patient on follow-up. The PAP regressed to normal in all except 5 cases (2.03%) of Down's syndrome with systemic PAP. Device closure of PDA with PAH is feasible, safe in all age groups. Temporary PDA occlusion with device is effective and time saving for evaluating pulmonary vascular reactivity. Device embolization in aorta is higher with severe PAH. Novel method of retrieval is effective. © 2014, Wiley Periodicals, Inc.

A Practical Scoring System to Select Optimally Sized Devices for Percutaneous Patent Foramen Ovale Closure.

PubMed

Venturini, Joseph M; Retzer, Elizabeth M; Estrada, J Raider; Mediratta, Anuj; Friant, Janet; Nathan, Sandeep; Paul, Jonathan D; Blair, John; Lang, Roberto M; Shah, Atman P

2016-10-01

Patent foramen ovale (PFO) has been linked to cryptogenic stroke, and closure has been reported to improve clinical outcomes. However, there are no clear guidelines to direct device sizing. This study sought to use patient characteristics and echocardiographic findings to create a prediction score for device sizing. This was a retrospective review of patients undergoing percutaneous PFO closure at our institution between July 2010 and December 2014. Demographic and clinical characteristics were recorded, and all pre- and intraprocedural echocardiography results were evaluated. Thirty-six patients underwent percutaneous PFO closure during the study period. All procedures were performed using an Amplatzer Septal Occluder "Cribriform" (ASOC) device in one of three disc diameters: 25, 30, or 35 mm. Closure was indicated for cryptogenic stroke/transient ischemic attack in 75% of cases. Every case (100%) was successful with durable shunt correction at the 6-month follow-up without complications of erosion or device embolization. The presence of atrial septal aneurysm (ASA) ( p = 0.027) and PFO tunnel length >10 mm ( p = 0.038) were independently associated with increased device size. A scoring system of 1 point for male sex, 1 point for ASA, and 1 point for PFO tunnel >10 mm long was associated with the size of closure device implanted ( p = 0.006). A simple scoring system may be used to select an optimally sized device for percutaneous PFO closure using the ASOC device.

Analysis and simulation of a magnetic bearing suspension system for a laboratory model annular momentum control device

NASA Technical Reports Server (NTRS)

Groom, N. J.; Woolley, C. T.; Joshi, S. M.

1981-01-01

A linear analysis and the results of a nonlinear simulation of a magnetic bearing suspension system which uses permanent magnet flux biasing are presented. The magnetic bearing suspension is part of a 4068 N-m-s (3000 lb-ft-sec) laboratory model annular momentum control device (AMCD). The simulation includes rigid body rim dynamics, linear and nonlinear axial actuators, linear radial actuators, axial and radial rim warp, and power supply and power driver current limits.

40 CFR 63.946 - Inspection and monitoring requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... its foundation mountings; broken, cracked, or otherwise damaged seals or gaskets on closure devices; and broken or missing hatches, access covers, caps, or other closure devices. (2) The owner or...; broken, cracked, or otherwise damaged seals or gaskets on closure devices; and broken or missing hatches...

40 CFR 63.1047 - Inspection and monitoring requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... separator wall; broken, cracked, or otherwise damaged seals or gaskets on closure devices; and broken or... the surface of the liquid in the separator; broken, cracked, or otherwise damaged seals or gaskets on closure devices; and broken or missing hatches, access covers, caps, or other closure devices. (ii) The...

Anatomy of the patent foramen ovale for the interventionalist.

PubMed

McKenzie, Jeff A; Edwards, William D; Hagler, Donald J

2009-05-01

Patent foramen ovale (PFO) is an interatrial communication whose management is controversial. Several manufacturers have submitted protocols for Food and Drug Administration (FDA) approval of their PFO closure device. The purpose of this study was to define anatomy relevant to percutaneous PFO closure, validate the clinical observation that most PFOs contain little tissue rim at the aorta, comment on proposed closure guidelines, and to discuss approaches to PFO closure. From the Mayo Clinic Tissue Registry, five normal hearts with PFO were selected from each sex from the first 10 decades of life (n = 100). Measurements (mm) included PFO length, diameter, and distance from FO-superior vena cava (SVC) and FO-aortic annulus (AoAn). Patient age, weight, and height were obtained from autopsy reports, and body surface area (BSA) was calculated. PFO length and diameter increased with age (P = 0.029 and 0.001, respectively), and FO-SVC and FO-AoAn increased with BSA (P

Changes in mitral annular and left ventricular dimensions and left ventricular pressure-volume relations after off-pump treatment of mitral regurgitation with the Coapsys device.

PubMed

Fukamachi, Kiyotaka; Popović, Zoran B; Inoue, Masahiro; Doi, Kazuyoshi; Schenk, Soren; Ootaki, Yoshio; Kopcak, Michael W; McCarthy, Patrick M

2004-03-01

The objective of this study was to evaluate the changes in mitral annular and left ventricular dimensions and left ventricular pressure-volume relations produced by the Myocor Coapsys device that has been developed to treat functional mitral regurgitation (MR) off-pump. The Coapsys device, which consists of anterior and posterior epicardial pads connected by a sub-valvular chord, was implanted in seven dogs with functional MR resulting from pacing induced cardiomyopathy. The Coapsys device was then sized by drawing the posterior leaflet and annulus toward the anterior leaflet. During sizing, MR grade was assessed using color flow Doppler echocardiography. Final device size was selected when MR was eliminated or minimized. Following implantation, heart failure was maintained by continued pacing for a period of 8 weeks. Mitral annular and left ventricular dimensions and left ventricular pressure-volume relations were evaluated by two-dimensional echocardiography and a conductance catheter, respectively, at pre-sizing, post-sizing, and after 8 weeks. All implants were performed on beating hearts without cardiopulmonary bypass. Mean MR grade was reduced from 2.9+/-0.7 at pre-sizing to 0.7+/-0.8 at post-sizing (P<0.001), and was maintained at 0.8+/-0.8 after 8 weeks (P<0.01). The septal-lateral dimensions were significantly reduced at both mitral annular level [2.4+/-0.2 cm at pre-sizing, 1.5+/-0.3 cm at post-sizing (P<0.001) and 1.8+/-0.3 cm after 8 weeks (P<0.05)] and mid-papillary level [4.1+/-0.4 cm at pre-sizing, 2.4+/-0.2 cm at post-sizing (P<0.001) and 3.3+/-0.4 cm after 8 weeks (P<0.001)]. The end-systolic pressure-volume relation shifted leftward at post-sizing with a significantly steeper slope (P=0.03). There was a significant (P=0.03) leftward shift of the end-diastolic pressure-volume relation at post-sizing. After 8 weeks, these changes in pressure-volume relations tended to return to pre-sizing relations. The Coapsys device significantly reduced MR by treating both the mitral annular dilatation and the papillary muscle displacement. Despite these significant dimensional changes, the Coapsys device did not negatively affect the left ventricular pressure-volume relations.

All optical detection of picosecond spin-wave dynamics in 2D annular antidot lattice

NASA Astrophysics Data System (ADS)

Porwal, Nikita; Mondal, Sucheta; Choudhury, Samiran; De, Anulekha; Sinha, Jaivardhan; Barman, Anjan; Datta, Prasanta Kumar

2018-02-01

Novel magnetic structures with precisely controlled dimensions and shapes at the nanoscale have potential applications in spin logic, spintronics and other spin-based communication devices. We report the fabrication of 2D bi-structure magnonic crystal in the form of embedded nanodots in a periodic Ni80Fe20 antidot lattice structure (annular antidot) by focused ion-beam lithography. The spin-wave spectra of the annular antidot sample, studied for the first time by a time-resolved magneto-optic Kerr effect microscopy show a remarkable variation with bias field, which is important for the above device applications. The optically induced spin-wave spectra show multiple modes in the frequency range 14.7 GHz-3.5 GHz due to collective interactions between the dots and antidots as well as the annular elements within the whole array. Numerical simulations qualitatively reproduce the experimental results, and simulated mode profiles reveal the spatial distribution of the spin-wave modes and internal magnetic fields responsible for these observations. It is observed that the internal field strength increases by about 200 Oe inside each dot embedded within the hole of annular antidot lattice as compared to pure antidot lattice and pure dot lattice. The stray field for the annular antidot lattice is found to be significant (0.8 kOe) as opposed to the negligible values of the same for the pure dot lattice and pure antidot lattice. Our findings open up new possibilities for development of novel artificial crystals.

Atrial septum defect closure device in a beating heart, from the perspective of a researcher in artificial organs.

PubMed

Tomizawa, Yasuko

2012-12-01

Transcatheter closure of atrial septum defect (ASD) with a closure device is increasing, but the history of clinical use of this procedure is still short, and the efficacy and long-term safety remain unproved. The total number of closure devices implanted throughout the world has not been counted accurately. Therefore, the probability of complications occurring after implantation is uncertain. Device-related complications that occur suddenly late after implantation are life-threatening, and quite often necessitate emergency surgical intervention. In Japanese medical journals, authors reporting closure devices have mentioned no complications and problems in their facilities. Detailed studies of device-related complications and device removal have not been reported in Japan. In fact, this literature search found an unexpectedly large number of reports of various adverse events from many overseas countries. When follow-up duration is short and the number of patients is small, the incidence of complications cannot be determined. Rare complications may emerge in a large series with a long observation period. Consequently, the actual number of incidents related to ASD closure devices is possibly several times higher than the number reported. Guidelines for long-term patient management for patients with an implanted closure device are necessary and post-marketing surveillance is appropriate. Development of a national database, a worldwide registration system, and continuous information disclosure will improve the quality of treatment. The devices currently available are not ideal in view of reports of late complications requiring urgent surgery and the need for life-long follow-up. An ideal device should be free from complications during life, and reliability is indispensable.

Short-term safety and efficacy of left atrial appendage closure with the WATCHMAN device in patients with small left atrial appendage ostia.

PubMed

Venkataraman, Ganesh; Strickberger, S Adam; Doshi, Shephal; Ellis, Christopher R; Lakkireddy, Dhanunjaya; Whalen, S Patrick; Cuoco, Frank

2018-01-01

Left atrial appendage (LAA) closure with the WATCHMAN device, according to FDA labelling, is recommended in patients with a maximal LAA ostial width between 17 and 31 mm. The safety and efficacy of LAA closure in patients with a maximal LAA ostial width < 17 mm has not been evaluated. The goal of this study was to determine the acute and short-term safety and efficacy of LAA closure with the WATCHMAN device in patients with a maximal LAA ostial width < 17 mm. Thirty-two consecutive patients with a maximal LAA ostial width < 17 mm as determined by a screening transesophageal echocardiogram (TEE) underwent LAA closure with the WATCHMAN device between March 2015 and November 2016 at five medical centers, and were included in this study. Mean age, body mass index (BMI), and CHA 2 DS 2 -VASC score were 70.8 ± 8.6 years, 29.3 ± 6.5 kg/m 2 , and 3.9 ±1.2, respectively. At the screening TEE, mean maximal LAA ostial width and depth were 15.6 ± 0.6 mm (range 14-16) and 23.2 ± 4.5 mm (range 13-31), respectively. Successful LAA closure with the WATCHMAN device was achieved in 31 of 32 patients (97%), with no major complications. TEE performed 45 days after LAA closure demonstrated no peridevice leak > 5 mm and no device related thrombi. Warfarin was discontinued in all 31 patients 45 days after LAA closure. LAA closure with the WATCHMAN device can be successfully and safely achieved in patients with a maximal LAA ostial width < 17 mm. © 2017 Wiley Periodicals, Inc.

Echocardiographic predictors of coil vs device closure in patients undergoing percutaneous patent ductus arteriosus closure.

PubMed

Roushdy, Alaa; Abd El Razek, Yasmeen; Mamdouh Tawfik, Ahmed

2018-01-01

To determine anatomic and hemodynamic echocardiographic predictors for patent ductus arteriosus (PDA) device vs coil closure. Seventy-six patients who were referred for elective transcatheter PDA closure were enrolled in the study. All patients underwent full echocardiogram including measurement of the PDA pulmonary end diameter, color flow width and extent, peak and end-diastolic Doppler gradients across the duct, diastolic flow reversal, left atrial dimensions and volume, left ventricular sphericity index, and volumes. The study group was subdivided into 2 subgroups based on the mode of PDA closure whether by coil (n = 42) or device (n = 34). Using univariate analysis there was a highly significant difference between the 2 groups as regard the pulmonary end diameter measured in both the suprasternal and parasternal short-axis views as well as the color flow width and color flow extent (P < .0001). The device closure group had statistically significant higher end-systolic and end-diastolic volumes indexed, left atrial volume, and diastolic flow reversal. Receiver operating characteristic curve analysis showed a pulmonary end diameter cutoff point from the suprasternal view > 2.5 mm and from parasternal short-axis view > 2.61 mm to have the highest balanced sensitivity and specificity to predict the likelihood for device closure (AUC 0.971 and 0.979 respectively). The pulmonary end diameter measured from the suprasternal view was the most independent predictor of device closure. The selection between PDA coil or device closure can be done on the basis of multiple anatomic and hemodynamic echocardiographic variables. © 2017 Wiley Periodicals, Inc.

Overview of magnetic suspension research at Langley Research Center

NASA Technical Reports Server (NTRS)

Groom, Nelson J.

1992-01-01

An overview of research in small- and large-gap magnetic suspension systems at LaRC is presented. The overview is limited to systems which have been built as laboratory models or engineering models. Small-gap systems applications include the Annular Momentum Control Device (AMCD), which is a momentum storage device for the stabilization and control of spacecraft, and the Annular Suspension and Pointing System (ASPS), which is a general purpose pointing mount designed to provide orientation, mechanical isolation, and fine pointing space experiments. These devices are described and control and linearization approaches for the magnetic suspension systems for these devices are discussed. Large-gap systems applications at LaRC have been almost exclusively wind tunnel magnetic suspension systems. A brief description of these efforts is also presented.

Transcutaneous closure of chronic broncho-pleuro-cutaneous fistula by duct occluder device

PubMed Central

Marwah, Vikas; Ravikumar, R; Rajput, Ashok Kumar; Singh, Amandeep

2016-01-01

Bronchopleural fistula (BPF) is a well known complication of several pulmonary conditions posing challenging management problem and is often associated with high morbidity and mortality. Though no consensus exists on a definite closure management algorithm, strategies for closure widely include various methods like tube thoracostomy with suction, open surgical closure, bronchoscopy directed glue, coiling and sealants which now also includes use of occlusion devices. We report a case in which a novel method of delivery and closure of recurrent post-operative broncho-pleuro-cutaneous fistula by a duct occluder device was done transcutaneously which has not been previously described in literature. PMID:27051115

Early decision-analytic modeling - a case study on vascular closure devices.

PubMed

Brandes, Alina; Sinner, Moritz F; Kääb, Stefan; Rogowski, Wolf H

2015-10-27

As economic considerations become more important in healthcare reimbursement, decisions about the further development of medical innovations need to take into account not only medical need and potential clinical effectiveness, but also cost-effectiveness. Already early in the innovation process economic evaluations can support decisions on development in specific indications or patient groups by anticipating future reimbursement and implementation decisions. One potential concept for early assessment is value-based pricing. The objective is to assess the feasibility of value-based pricing and product design for a hypothetical vascular closure device in the pre-clinical stage which aims at decreasing bleeding events. A deterministic decision-analytic model was developed to estimate the cost-effectiveness of established vascular closure devices from the perspective of the Statutory Health Insurance system. To identify early benchmarks for pricing and product design, three strategies of determining the product's value are explored: 1) savings from complications avoided by the new device; 2) valuation of the avoided complications based on an assumed willingness-to-pay-threshold (the efficiency frontier approach); 3) value associated with modifying the care pathways within which the device would be applied. Use of established vascular closure devices is dominated by manual compression. The hypothetical vascular closure device reduces overall complication rates at higher costs than manual compression. Maximum cost savings of only about €4 per catheterization could be realized by applying the hypothetical device. Extrapolation of an efficiency frontier is only possible for one subgroup where vascular closure devices are not a dominated strategy. Modifying care in terms of same-day discharge of patients treated with vascular closure devices could result in cost savings of €400-600 per catheterization. It was partially feasible to calculate value-based prices for the novel closure device which can be used to inform product design. However, modifying the care pathway may generate much more value from the payers' perspective than modifying the device per se. Manufacturers should thus explore the feasibility of combining reimbursement of their product with arrangements that make same-day discharge attractive also for hospitals. Due to the early nature of the product, the results are afflicted with substantial uncertainty.

Comparison of two spectral domain optical coherence tomography devices for angle-closure assessment.

PubMed

Quek, Desmond T; Narayanaswamy, Arun K; Tun, Tin A; Htoon, Hla M; Baskaran, Mani; Perera, Shamira A; Aung, Tin

2012-08-03

To compare two spectral domain optical coherence tomography (SD-OCT) devices for the identification of angle structures and the presence of angle closure. This was a prospective comparative study. Consecutive patients underwent gonioscopy and anterior segment imaging using two SD-OCT devices (iVue and Cirrus). Images were evaluated for the ability to detect angle structures such as Schwalbe's line (SL), trabecular meshwork (TM), Schlemm's canal (SC), and scleral spur (SS), and the presence of angle closure. Angle closure was defined as iris contact with the angle wall anterior to the SS on SD-OCT, and nonvisibility of the posterior TM on gonioscopy. Angle closure in an eye was defined as ≥two quadrants of closed angles. AC1 statistic was used to assess the agreement between devices. Of the 69 subjects studied (46.4% male, 84.1% Chinese, mean age 64.0 ± 10.5 years), 40 subjects (40 eyes, 58.0%) had angle closure on gonioscopy. The most identifiable structure on Cirrus SD-OCT was the SS (82.2%) and SL on iVue SD-OCT (74.5%). Angle closure was indeterminable in 14.5% and 50.7% of Cirrus and iVue scans (P < 0.001), respectively. Interdevice agreement for angle closure was moderately strong (AC1 = 0.67), but agreement with gonioscopy was only fair (AC1 = 0.35 and 0.50 for Cirrus and iVue, respectively). It was more difficult to determine angle closure status with iVue compared with Cirrus SD-OCT. There was fair agreement between both devices with gonioscopy for identifying angle closure.

[Percutaneous closure of atrial septal defects with the Amplatzer® device: 15 years of experience].

PubMed

Zabal-Cerdeira, Carlos; García-Montes, José Antonio; Sandoval-Jones, Juan Pablo; Calderón-Colmenero, Juan; Patiño-Bahena, Emilia; Juanico-Enríquez, Antonio; Buendía-Hernández, Alfonso

2014-01-01

Percutaneous closure of atrial septal defects is an alternative to surgical treatment. We report the results of percutaneous closure of atrial septal defects with the Amplatzer(®) device. We include patients taken to the catheterization laboratory from September 1997 to December 2011. We proceeded with defect closure in 721 patients and in 85 the defect was considered not suitable for closure. The stretched diameter of the defect was 23±6.7mm (limits, 5-42). All devices were positioned successfully. In 15 cases (2.1%) the device was changed due to instability and in 6 (0.8%) the device embolized within the first 24h, 4 were retrieved and repositioned (final success with intention to treat 719/806-89.2%). Immediate control showed complete closure in 247 patients (34.3%), leak through the device in 395 (54.9%), mild residual leak in 75 (10.4%) and moderate in 2 (0.3%). We have follow-up in 626 patients (87.1%) for 33±27.5 months, with headache in 54 (8.6%), new supraventricular arrhythmia in 10 (1.6%), puncture site complications in 4 (0.6%), and stroke in one (0.1%). The design of the Amplatzer(®) device allows effective closure of atrial septal defects with a simple technique and patient safety. Copyright © 2013 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

Contemporary outcomes of percutaneous closure of patent ductus arteriosus in adolescents and adults.

PubMed

P, Sudhakar; Jose, John; George, Oommen K

Catheter based treatment has gained wide acceptance for management of patent ductus arteriosus (PDA) ever since its introduction. Percutaneous closure in adults can be challenging because of anatomical factors including large sizes, associated pulmonary arterial hypertension (PAH) and co-morbidities. This study aimed to provide comprehensive contemporary data on the safety and efficacy of percutaneous device closure of PDA in adult and adolescent population at a large referral center. This single-center retrospective analysis included 70 patients (33 adolescents and 37 adults) who underwent successful percutaneous device closure of PDA between January 2011 and February 2017.Baseline patient demographics, clinical characteristics, procedural and device related variables, and immediate outcomes during hospital stay were recorded. Patients were followed up for residual shunt and complications. Of 70 PDA device closure cases, 71.4% were females; the mean age was 23 years (range:10-58years). Devices used were 4-Cook's detachable coils, 64-occluders (ADO-I and II, Lifetech, Cardi-O-Fix), 1-vascular plug and 1-ventricular septal occluder device. Device success was achieved in all including those with very large PDAs. At 24-h post-procedure, the success rate of transcatheter intervention was 95.7%. At 6-months follow up, complete closure was observed in all (mean follow up duration-531days). In patients with severe PAH, significant immediate and sustained reduction of the mean pulmonary pressure was observed(77mmHg to 33mmHg;P=0.014). No procedure-related complications including death, device embolization and stenosis of aorta or pulmonary artery occurred. In contemporary practice, percutaneous device closure is an effective and safe treatment option for adolescent and adult PDA patients. Copyright © 2017. Published by Elsevier B.V.

Suitability of Exoseal Vascular Closure Device for Antegrade Femoral Artery Puncture Site Closure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmelter, Christopher, E-mail: christopher.schmelter@klinikum-ingolstadt.de; Liebl, Andrea; Poullos, Nektarios

Purpose. To assess the efficacy and safety of the Exoseal vascular closure device for antegrade puncture of the femoral artery. Methods. In a prospective study from February 2011 to January 2012, a total of 93 consecutive patients received a total of 100 interventional procedures via an antegrade puncture of the femoral artery. An Exoseal vascular closure device (6F) was used for closure in all cases. Puncture technique, duration of manual compression, and use of compression bandages were documented. All patients were monitored by vascular ultrasound and color-coded duplex sonography of their respective femoral artery puncture site within 12 to 36more » h after angiography to check for vascular complications. Results. In 100 antegrade interventional procedures, the Exoseal vascular closure device was applied successfully for closure of the femoral artery puncture site in 96 cases (96 of 100, 96.0 %). The vascular closure device could not be deployed in one case as a result of kinking of the vascular sheath introducer and in three cases because the bioabsorbable plug was not properly delivered to the extravascular space adjacent to the arterial puncture site, but instead fully removed with the delivery system (4.0 %). Twelve to 36 h after the procedure, vascular ultrasound revealed no complications at the femoral artery puncture site in 93 cases (93.0 %). Minor vascular complications were found in seven cases (7.0 %), with four cases (4.0 %) of pseudoaneurysm and three cases (3.0 %) of significant late bleeding, none of which required surgery. Conclusion. The Exoseal vascular closure device was safely used for antegrade puncture of the femoral artery, with a high rate of procedural success (96.0 %), a low rate of minor vascular complications (7.0 %), and no major adverse events.« less

Patent foramen ovale closure using a bioabsorbable closure device: safety and efficacy at 6-month follow-up.

PubMed

Van den Branden, Ben J; Post, Martijn C; Plokker, Herbert W; ten Berg, Jurriën M; Suttorp, Maarten J

2010-09-01

The aim of this study was to assess the mid-term safety and efficacy of percutaneous patent foramen ovale (PFO) closure using a bioabsorbable device (BioSTAR, NMT Medical, Boston, Massachusetts). Closure of PFO in patients with cryptogenic stroke has proven to be safe and effective using different types of permanent devices. All consecutive patients who underwent percutaneous PFO closure with the bioabsorbable closure device between November 2007 and January 2009 were included. Residual shunt was assessed using contrast transthoracic echocardiography. Sixty-two patients (55% women, mean age 47.7 ± 11.8 years) underwent PFO closure. The in-hospital complications were a surgical device retrieval in 2 patients (3.2%), device reposition in 1 (1.6%), and a minimal groin hematoma in 6 patients (9.7%). The short-term complications at 1-month follow-up (n = 60) were a transient ischemic attack in the presence of a residual shunt in 1 patient and new supraventricular tachycardia in 7 patients (11.3%). At 6-month follow-up (n = 60), 1 patient without residual shunt developed a transient ischemic attack and 1 developed atrial fibrillation. A mild or moderate residual shunt was noted in 51.7%, 33.9%, and 23.7% after 1-day, 1-month, and 6-month follow-up, respectively. A large shunt was present in 8.3%, 3.4%, and 0% after 1-day, 1-month, and 6-month follow-up. Closure of PFO using the bioabsorbable device is associated with a low complication rate and a low recurrence rate of embolic events. However, a relatively high percentage of mild or moderate residual shunting is still present at 6-month follow-up. Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Transcatheter umbrella closure of valvular and paravalvular leaks.

PubMed

Hourihan, M; Perry, S B; Mandell, V S; Keane, J F; Rome, J J; Bittl, J A; Lock, J E

1992-11-15

Our aim was to adapt the technique of transcatheter umbrella closure of intracardiac defects for closure of valvular and paravalvular defects. The double-umbrella device developed by Rashkind and Cuaso has been safely and effectively delivered across a host of intracardiac defects, but transcatheter closure of valvular and paravalvular leaks has not been reported. Between February 1987 and September 1990, eight patients who were believed to be poor operative candidates were taken to the catheterization laboratory for transcatheter double-umbrella closure of a valvular or a paravalvular leak. Four patients had a paravalvular leak around a prosthetic aortic valve. The other four patients had a valvular leak: one patient with a regurgitant native aortic valve after a Stansel procedure and three patients with a regurgitant porcine valve in a left ventricular apex to descending aorta conduit. Placement of a double-umbrella device was attempted in seven of the eight patients and was successful in all seven. Device placement was not attempted in one patient because of the crescentic shape of his defect. Two patients required two devices for each closure; the other five required only one device each. Angiography, performed on six patients after device closure, demonstrated that three patients had a completely occluded defect, two had trivial residual flow and one patient had mild residual flow through the device. All significant complications occurred in one patient who had hemolysis and oliguria that resolved when the initial umbrella was replaced by a larger device. In addition, two devices migrated to the patient's pulmonary arteries but were retrieved in the catheterization laboratory without difficulty. No other early or late complications occurred in 21 to 50 months of follow-up. Of the four patients with a paravalvular leak, the one who did not receive a device died at operation, one patient died at operation for an associated defect (in the operating room the umbrella was found securely in place across the paraaortic defect) and two patients are clinically well at home after 21 and 32 months, respectively. Of the four patients with closure of a valvular leak, one patient remains well at home 50 months later, one patient died at operation for associated defects and two patients had additional successful surgical treatment and remain well 29 months after device placement. Transcatheter umbrella closure appears to be a reasonable alternative for closure of a valvular or paravalvular leak in patients who are poor operative candidates.

Predicting Peri-Device Leakage of Left Atrial Appendage Device Closure Using Novel Three-Dimensional Geometric CT Analysis.

PubMed

Chung, Hyemoon; Jeon, Byunghwan; Chang, Hyuk-Jae; Han, Dongjin; Shim, Hackjoon; Cho, In Jeong; Shim, Chi Young; Hong, Geu-Ru; Kim, Jung-Sun; Jang, Yangsoo; Chung, Namsik

2015-12-01

After left atrial appendage (LAA) device closure, peri-device leakage into the LAA persists due to incomplete occlusion. We hypothesized that pre-procedural three-dimensional (3D) geometric analysis of the interatrial septum (IAS) and LAA orifice can predict this leakage. We investigated the predictive parameters of LAA device closure obtained from baseline cardiac computerized tomography (CT) using a novel 3D analysis system. We conducted a retrospective study of 22 patients who underwent LAA device closure. We defined peri-device leakage as the presence of a Doppler signal inside the LAA after device deployment (group 2, n = 5) compared with patients without peri-device leakage (group 1, n = 17). Conventional parameters were measured by cardiac CT. Angles θ and φ were defined between the IAS plane and the line, linking the LAA orifice center and foramen ovale. Group 2 exhibited significantly better left atrial (LA) function than group 1 (p = 0.031). Pre-procedural θ was also larger in this group (41.9° vs. 52.3°, p = 0.019). The LAA cauliflower-type morphology was more common in group 2. Overall, the patients' LA reserve significantly decreased after the procedure (21.7 mm(3) vs. 17.8 mm(3), p = 0.035). However, we observed no significant interval changes in pre- and post-procedural values of θ and φ in either group (all p > 0.05). Angles between the IAS and LAA orifice might be a novel anatomical parameter for predicting peri-device leakage after LAA device closure. In addition, 3D CT analysis of the LA and LAA orifice could be used to identify clinically favorable candidates for LAA device closure.

Goose-neck snare-assisted transcatheter ASD closure: A safety procedure for large and complex ASDs.

PubMed

Butera, Gianfranco; Lovin, Nicusor; Basile, Domenica Paola; Carminati, Mario

2016-04-01

To report on a new technique that increases the safety of percutaneous atrial septal defect (ASD) closure using a goose-neck snare system. ASD transcatheter closure is a widespread procedure. However, in some cases, ASDs may be large and with soft rims. In these situation, a potential risk exists for device malposition or embolization. When transesophageal echocardiography (TEE) evaluation and balloon sizing showed large defects with floppy rims the chosen Amplatzer device was implanted in a standard way. In large defects with floppy rims, before release a 5-mm goose-neck snare with its 4 Fr catheter was placed across the delivery cable and fixed to catch the screwing mechanism of implanted Amplatzer device. The delivery cable was unscrewed and the device reached its final position without any tension. If the position was considered satisfactory the device was released from the goose-neck snare. Thirteen patients had a snare-assisted ASD transcatheter closure. Median device size was 24 mm (range 14-38 mm). Retrieval or repositioning of the device using the goose-neck snare was performed in four cases: in three patients, because of device malposition after delivery cable release and in one patient, because of unsuitability of closure of a second significant defect. Furthermore, in two subjects with multiple ASDs, a second fenestration looked quite significant with the device still attached to the delivery cable while it appeared smaller after release. Snare-assisted Amplatzer ASD device placement is a new method for ASD percutaneous closure and adds safety to the procedure. © 2016 Wiley Periodicals, Inc.

Device for controlling the pouring of molten materials

DOEpatents

Moore, A.F.; Duncan, A.L.

1994-02-15

A device is described for controlling the pouring of a molten material from a crucible or other container. The device includes an annular retainer ring for mounting in the drain opening in the bottom of a conventional crucible, the retainer ring defining a opening there through. The device also includes a plug member having an annular forward end portion for force-fit reception in the opening of the retainer ring to selectively seal the opening and for being selectively forced through the opening. The plug member has a rear end portion for being positioned within the crucible, the rear end portion including stop means for prohibiting the rear end portion from passing through the opening in the retainer ring when the forward end portion is selectively forced through the opening. The plug member defines at least one, and preferably a plurality of flutes, each extending from a point rearward the annular forward end portion of the plug member, and forward the stop means, to a point rearward of the stop means. The flutes permit fluid communication between the interior and exterior of the crucible when the forward end portion of the plug member is forced through the opening in the retaining ring such that the molten material is allowed to flow from the crucible. 5 figures.

Predictive Factors for Patients Undergoing ASD Device Occlusion Who "Crossover" to Surgery.

PubMed

Mulukutla, Venkatachalam; Qureshi, Athar M; Pignatelli, Ricardo; Ing, Frank F

2018-03-01

The aim of this study was to define characteristics of those patients who are referred for device closure of an Atrial septal defect (ASD), but identified to "crossover" surgery. All patients who underwent surgical and device (Amplatzer or Helex occluder) closures of secundum ASDs from 2001 to 2010 were reviewed and organized into three groups: surgical closure, device closure, and "crossover" group. 369 patients underwent ASD closure (265 device, 104 surgical). 42 of the 265 patients referred for device closure "crossed over" to the surgical group at various stages of the catheterization procedure. The device group had defect size measuring 14.2 mm (mean) and an ASD index (Defect Size (mm)/BSA) of 14.0 compared to the corresponding values in the surgical group (20.1 mm, ASD index 25.9) (P < 0.001) and in the "crossover" group (20.7 mm, 22.6 ASD index) (P < 0.001). 79 patients in the device group had a deficient rim, and 86% were located in the retroaortic region. 33 patients in the "crossover" group had deficient rims with 70% deficiency in the posterior/inferior rim. The device group with deficient rims had an ASD index of 14.7 compared with the crossover group ASD index of 23.8 (P < 0.001). Comparing the device and "crossover" groups, an ASD index greater than 23.7 had a 90% specificity in "crossing over" to surgery. The crossover and surgical groups had statistically larger ASD defect size indexes compared with the device group. Deficient rim in the posterior/inferior rim is associated with a large ASD size index which is a predictive factor for crossing over to surgery. Catheterization did not negatively impact surgical results in the "crossover" group.

Perventricular double-device closure of wide-spaced multi-hole perimembranous ventricular septal defect.

PubMed

Liang, Fei; Hongxin, Li; Zhang, Hai-Zhou; Wenbin, Guo; Zou, Cheng-Wei; Farhaj, Zeeshan

2017-04-17

Device closure of a wide-spaced multi-hole PmVSD is difficult to succeed in percutaneous approach. This study is to evaluate the feasibility, safety and efficacy of perventricular device closure of wide-spaced multi-hole PmVSD using a double-device implanting technique. Sixteen patients with wide-spaced multi-hole PmVSD underwent perventricular closure with two devices through an inferior median sternotomy approach under transesophageal echocardiographic guidance. The largest hole and its adjacent small holes were occluded with an optimal-sized device. The far-away residual hole was occluded with the other device using a probe-assisted delivery system. All patients were followed up for a period of 1 to 4 years to determine the residual shunt, atrioventricular block and the adjacent valvular function. The number of the holes of the PmVSD was 2 to 4. The maximum distance between the holes was 5.0 to 10.0 mm (median, 6.4 mm). The diameter of the largest hole was 2.5 to 7.0 mm (median, 3.6 mm). The success rate of double-device closure was 100%. Immediate residual shunts were found in 6 patients (38%), and incomplete right bundle branch block at discharge occurred in 3 cases (19%). Both complications decreased to 6% at 1-year follow-up. Neither of them had a severe device-related complication. Perventricular closure of a wide-spaced multi-hole PmVSD using a double-device implanting technique is feasible, safe, and efficacious. In multi-hole PmVSDs with the distance between the holes of more than 5 mm, double-device implantation may achieve a complete occlusion.

Challenges in device closure of a large patent ductus arteriosus in infants weighing less than 6 kg.

PubMed

Vijayalakshmi, I B; Chitra, Narasimhan; Praveen, Jayan; Prasanna, Simha Rao

2013-02-01

Transcatheter closure of patent ductus arteriosus (PDA) has replaced surgery in most institutions. Despite improvements in techniques and the devices available, closure of large PDA in very small infants remains a challenge. To assess the challenges, feasibility, and efficacy of device closure of large PDA, in infants weighing ≤6 kg. Analysis of device closure of a PDA was done in 61 infants ≤6 kg. Their ages, ranged from 9 days-12 months (mean 8.9 months), weight ranged from 2.2 to 6 kg (mean 5.3 kg), and PDA measured 3.2-8.7 mm (mean 4.8 mm). The fluoroscopy time was 3-18 minutes. The largest device used was 12 × 10 mm. Successful device placement was achieved in 60/61 infants (98.4%). Mild aortic obstruction occurred in 2 cases (3.3%), as the device got displaced towards the aorta after release. The device embolized in 2 cases (3.3%). In one it was retrieved by a novel method like fastening the screw in the aorta and was closed with a 4 × 6 ADO II. In the other infant, with a single kidney, died of uremia after device retrieval. Mild left pulmonary artery (LPA) obstruction occurred in one case (1.6%). Four cases (6.6%) had minor vascular complications. The postprocedure weight gain after 3 months was between 2.5 kg ± 250 mg. Device closure of large PDA in infants weighing ≤6 kg with left ventricular failure is challenging but possible, safe and effective. Retrieval of embolized device could be tricky. © 2012, Wiley Periodicals, Inc.

ASD Closure in Structural Heart Disease.

PubMed

Wiktor, Dominik M; Carroll, John D

2018-04-17

While the safety and efficacy of percutaneous ASD closure has been established, new data have recently emerged regarding the negative impact of residual iatrogenic ASD (iASD) following left heart structural interventions. Additionally, new devices with potential advantages have recently been studied. We will review here the potential indications for closure of iASD along with new generation closure devices and potential late complications requiring long-term follow-up. With the expansion of left-heart structural interventions and large-bore transseptal access, there has been growing experience gained with management of residual iASD. Some recently published reports have implicated residual iASD after these procedures as a potential source of diminished clinical outcomes and mortality. Additionally, recent trials investigating new generation closure devices as well as expanding knowledge regarding late complications of percutaneous ASD closure have been published. While percutaneous ASD closure is no longer a novel approach to managing septal defects, there are several contemporary issues related to residual iASD following large-bore transseptal access and new generation devices which serve as an impetus for this review. Ongoing attention to potential late complications and decreasing their incidence with ongoing study is clearly needed.

Tulip deformity with Cera atrial septal defect devices: a report of 3 cases.

PubMed

Kohli, Vikas

2015-02-01

Device closure of secundum atrial septal defect (ASD) is the treatment of choice when anatomy is favourable. Amplatzer device has remained the gold standard for closure of ASD. Cobra deformity is a well-reported problem with devices. Recently, Tulip deformity has been reported in a single case. We report a series of cases where we noted Tulip deformity along with inability to retract the device in the sheath in Cera Lifetech devices. This resulted in prolongation of procedure, excessive fluoroscopic exposure and additional interventional procedures not usually anticipated in ASD device closure. We believe that the problem is due to the stiffness of the device resulting in its inability to be retracted into the sheath. We also report a unique way of retrieving the device.

Transcatheter closure of post-operative residual ventricular septal defect using a patent ductus arteriosus closure device in an adult: a case report.

PubMed

Djer, Mulyadi M; Idris, Nikmah S; Alwi, Idrus; Wijaya, Ika P

2014-07-01

Transcatheter closure of perimembranous and muscular ventricular septal defect (VSD) has been performed widely and it has more advantages compare to surgery. However, transcatheter closure of residual VSD post operation of complex congenital heart disease is still challenging because of the complexity of anatomy and concern about device stability, so the operator should meticulously choose the most appropriate technique and device. We would like to report a case of transcatheter closure of residual VSD post Rastelli operation in a patient with double outlet right ventricle (DORV), sub-aortic VSD, severe infundibulum pulmonary stenosis (PS) and single coronary artery. The patient had undergone operations for four times, but he still had intractable heart failure that did not response to medications. On the first attempt. we closed the VSD using a VSD occluder, unfortunately the device embolized into the descending aorta, but fortunately we was able to snare it out. Then we decided to close the VSD using a patent ductus arteriosus (PDA occluder). On transesophageal echocardiography (TEE) and angiography evaluation, the device position was stable. Post transcatheter VSD closure, the patient clinical condition improved significantly and he could finally be discharged after a long post-surgery hospitalization. Based on this experience we concluded that the transcatheter closure of residual VSD in complex CHD using PDA occluder could be an effective alternative treatment.

The TopClosure® 3S System, for skin stretching and a secure wound closure.

PubMed

Topaz, Moris; Carmel, Narin-Nard; Silberman, Adi; Li, Ming Sen; Li, Yong Zhong

2012-07-01

The principle of stretching wound margins for primary wound closure is commonly practiced and used for various skin defects, leading at times to excessive tension and complications during wound closure. Different surgical techniques, skin stretching devices and tissue expanders have been utilized to address this issue. Previously designed skin stretching devices resulted in considerable morbidity. They were invasive by nature and associated with relatively high localized tissue pressure, frequently leading to necrosis, damage and tearing of skin at the wound margins. To assess the clinical effectiveness and performance and, to determine the safety of TopClosure® for gradual, controlled, temporary, noninvasive and invasive applications for skin stretching and secure wound closing, the TopClosure® device was applied to 20 patients for preoperative skin lesion removal and to secure closure of a variety of wound sizes. TopClosure® was reinforced with adhesives, staples and/or surgical sutures, depending on the circumstances of the wound and the surgeon's judgment. TopClosure® was used prior to, during and/or after surgery to reduce tension across wound edges. No significant complications or adverse events were associated with its use. TopClosure® was effectively used for preoperative skin expansion in preparation for dermal resection (e.g., congenital nevi). It aided closure of large wounds involving significant loss of skin and soft tissue by mobilizing skin and subcutaneous tissue, thus avoiding the need for skin grafts or flaps. Following surgery, it was used to secure closure of wounds under tension, thus improving wound aesthetics. A sample case study will be presented. We designed TopClosure®, an innovative device, to modify the currently practiced concept of wound closure by applying minimal stress to the skin, away from damaged wound edges, with flexible force vectors and versatile methods of attachment to the skin, in a noninvasive or invasive manner.

Performance characteristics of a novel blood bag in-line closure device and subsequent product quality assessment

PubMed Central

Serrano, Katherine; Levin, Elena; Culibrk, Brankica; Weiss, Sandra; Scammell, Ken; Boecker, Wolfgang F; Devine, Dana V

2010-01-01

BACKGROUND In high-volume processing environments, manual breakage of in-line closures can result in repetitive strain injury (RSI). Furthermore, these closures may be incorrectly opened causing shear-induced hemolysis. To overcome the variability of in-line closure use and minimize RSI, Fresenius Kabi developed a new in-line closure, the CompoFlow, with mechanical openers. STUDY DESIGN AND METHODS The consistency of the performance of the CompoFlow closure device was assessed, as was its effect on component quality. A total of 188 RBC units using CompoFlow blood bag systems and 43 using the standard bag systems were produced using the buffy coat manufacturing method. Twenty-six CompoFlow platelet (PLT) concentrates and 10 control concentrates were prepared from pools of four buffy coats. RBCs were assessed on Days 1, 21, and 42 for cellular variables and hemolysis. PLTs were assessed on Days 1, 3, and 7 for morphology, CD62P expression, glucose, lactate, and pH. A total of 308 closures were excised after processing and the apertures were measured using digital image analysis. RESULTS The use of the CompoFlow device significantly improved the mean extraction time with 0.46 ± 0.11 sec/mL for the CompoFlow units and 0.52 ± 0.13 sec/mL for the control units. The CompoFlow closures showed a highly reproducible aperture after opening (coefficient of variation, 15%) and the device always remained opened. PLT and RBC products showed acceptable storage variables with no differences between CompoFlow and control. CONCLUSIONS The CompoFlow closure devices improved the level of process control and processing time of blood component production with no negative effects on product quality. PMID:20529007

Prospective Comparison of Collagen Plug (Angio-Seal™) and Suture-Mediated (the Closer S™) Closure Devices at Femoral Access Sites

PubMed Central

Park, Yulri; Choo, Sung Wook; Lee, Sung Hoon; Shin, Sung Wook; Do, Young Soo; Byun, Hong Sik; Park, Kwang Bo; Jeon, Pyoung

2005-01-01

Objective Rapid and effective hemostasis at femoral puncture sites minimizes both the hospital stay and patient discomfort. Therefore, a variety of arterial closure devices have been developed to facilitate the closure of femoral arteriotomy. The objective of this prospective study was to compare the efficacy of two different closure devices; a collagen plug device (Angio-Seal) and a suture-mediated closure device (the Closer S). Materials and Methods From March 28, 2003 to August 31, 2004, we conducted a prospective study in which 1,676 cases of 1,180 patients were treated with two different types of closure device. Angio-Seal was used in 961 cases and the Closer S in 715 cases. The efficacy of the closure devices was assessed, as well as complications occurring at the puncture sites. Results Successful immediate hemostasis was achieved in 95.2% of the cases treated with Angio-Seal, and in 89.5% of the cases treated with the Closer S (p < 0.05). The rates of minor and major complications occurring between the two groups were not significantly different. In the Closer S group, we observed four major complications (0.6%), that consisted of one massive retroperitoneal hemorrhage (surgically explored) and three pseudoaneurysms. In the Angio-Seal group, we observed three major complications (0.3%) that consisted of one femoral artery occlusion, one case of infection treated with intravenous antibiotics and one pseudoaneurysm. Conclusion The use of Angio-Seal was found to be more effective than that of the Closer S with regard to the immediate hemostasis of the femoral puncture sites. However, we detected no significant differences in the rate at which complications occurred. PMID:16374083

Locking support for nuclear fuel assemblies

DOEpatents

Ledin, Eric

1980-01-01

A locking device for supporting and locking a nuclear fuel assembly within a cylindrical bore formed by a support plate, the locking device including a support and locking sleeve having upwardly extending fingers forming wedge shaped contact portions arranged for interaction between an annular tapered surface on the fuel assembly and the support plate bore as well as downwardly extending fingers having wedge shaped contact portions arranged for interaction between an annularly tapered surface on the support plate bore and the fuel assembly whereby the sleeve tends to support and lock the fuel assembly in place within the bore by its own weight while facilitating removal and/or replacement of the fuel assembly.

Tactical Sensors for Dispersed TNF (Tactical Nuclear Force) Units. Appendix 1.Tactical Sensory Survey.

DTIC Science & Technology

1983-06-30

activating a separate transmitter, audible alarm, or contact closure. This sensor is compatible with any device that utilizes an input pulse or...transmitter, audible alarm, or contact closure. This sensor is compatible *i with any device that utilizes an output to produce an alarm. 110-4769-002. This...used to generate an alarm by activating a separate transmitter, audible alarm, or contact closure. This sensor is compatible with any device that

Design of radial phononic crystal using annular soft material with low-frequency resonant elastic structures

NASA Astrophysics Data System (ADS)

Gao, Nansha; Wu, Jiu Hui; Yu, Lie; Xin, Hang

2016-10-01

Using FEM, we theoretically study the vibration properties of radial phononic crystal (RPC) with annular soft material. The band structures, transmission spectra, and displacement fields of eigenmode are given to estimate the starting and cut-off frequency of band gaps. Numerical calculation results show that RPC with annular soft material can yield low-frequency band gaps below 350 Hz. Annular soft material decreases equivalent stiffness of the whole structure effectively, and makes corresponding band gaps move to the lower frequency range. Physical mechanism behind band gaps is the coupling effect between long or traveling wave in plate matrix and the vibrations of corrugations. By changing geometrical dimensions of plate thickness e, the length of silicone rubber h2, and the corrugation width b, we can control the location and width of the first band gap. These research conclusions of RPC structure with annular soft material can potentially be applied to optimize band gaps, generate filters, and design acoustic devices.

Transcatheter closure of patent ductus arteriosus: past, present and future.

PubMed

Baruteau, Alban-Elouen; Hascoët, Sébastien; Baruteau, Julien; Boudjemline, Younes; Lambert, Virginie; Angel, Claude-Yves; Belli, Emre; Petit, Jérôme; Pass, Robert

2014-02-01

This review aims to describe the past history, present techniques and future directions in transcatheter treatment of patent ductus arteriosus (PDA). Transcatheter PDA closure is the standard of care in most cases and PDA closure is indicated in any patient with signs of left ventricular volume overload due to a ductus. In cases of left-to-right PDA with severe pulmonary arterial hypertension, closure may be performed under specific conditions. The management of clinically silent or very tiny PDAs remains highly controversial. Techniques have evolved and the transcatheter approach to PDA closure is now feasible and safe with current devices. Coils and the Amplatzer Duct Occluder are used most frequently for PDA closure worldwide, with a high occlusion rate and few complications. Transcatheter PDA closure in preterm or low-bodyweight infants remains a highly challenging procedure and further device and catheter design development is indicated before transcatheter closure is the treatment of choice in this delicate patient population. The evolution of transcatheter PDA closure from just 40 years ago with 18F sheaths to device delivery via a 3F sheath is remarkable and it is anticipated that further improvements will result in better safety and efficacy of transcatheter PDA closure techniques. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

MANTA, a novel plug-based vascular closure device for large bore arteriotomies: technical report.

PubMed

van Gils, Lennart; Daemen, Joost; Walters, Greg; Sorzano, Todd; Grintz, Todd; Nardone, Sam; Lenzen, Mattie; De Jaegere, Peter P T; Roubin, Gary; Van Mieghem, Nicolas M

2016-09-18

Catheter-based interventions have become a less invasive alternative to conventional surgical techniques for a wide array of cardiovascular diseases but often create large arteriotomies. A completely percutaneous technique is attractive as it may reduce the overall complication rate and procedure time. Currently, large bore arteriotomy closure relies on suture-based techniques. Access-site complications are not uncommon and often seem related to closure device failure. The MANTA VCD is a novel collagen-based closure device that specifically targets arteriotomies between 10 and 22 Fr. This technical report discusses the MANTA design concept, practical instructions for use and preliminary clinical experience.

Initial experience with the Cardiva Boomerang vascular closure device in diagnostic catheterization.

PubMed

Doyle, Brendan J; Godfrey, Michael J; Lennon, Ryan J; Ryan, James L; Bresnahan, John F; Rihal, Charanjit S; Ting, Henry H

2007-02-01

The authors studied the safety and efficacy of the Cardiva Boomerang vascular closure device in patients undergoing diagnostic cardiac catheterization. Conventional vascular closure devices (sutures, collagen plugs, or metal clips) have been associated with catastrophic complications including arterial occlusion and foreign body infections; furthermore, they cannot be utilized in patients with peripheral vascular disease or vascular access site in a vessel other than the common femoral artery. The Cardiva Boomerang device facilitates vascular hemostasis without leaving any foreign body behind at the access site, can be used in peripheral vascular disease, and can be used in vessels other than the common femoral artery A total of 96 patients undergoing transfemoral diagnostic cardiac catheterization were included in this study, including 25 (26%) patients with contraindications to conventional closure devices. Femoral angiography was performed prior to deployment of the Cardiva Boomerang closure device. Patients were ambulated at 1 hr after hemostasis was achieved. The device was successfully deployed and hemostasis achieved with the device alone in 95 (99%) patients. The device failed to deploy in 1 (1%) patient and required conversion to standard manual compression. Minor complications were observed in 5 (5%) patients. No patients experienced major complications including femoral hematoma > 4 cm, red blood cell transfusion, retroperitoneal bleed, arteriovenous fistula, pseudoaneurysm, infection, arterial occlusion, or vascular surgery. The Cardiva Boomerang device is safe and effective in patients undergoing diagnostic cardiac catheterization using the transfemoral approach, facilitating early ambulation with low rates of vascular complications. (c) 2006 Wiley-Liss, Inc.

Durability of central aortic valve closure in patients with continuous flow left ventricular assist devices.

PubMed

McKellar, Stephen H; Deo, Salil; Daly, Richard C; Durham, Lucian A; Joyce, Lyle D; Stulak, John M; Park, Soon J

2014-01-01

A competent aortic valve is essential to providing effective left ventricular assist device support. We have adopted a practice of central aortic valve closure by placing a simple coaptation stitch at left ventricular assist device implantation in patients with significant aortic insufficiency. We conducted a follow-up study to evaluate the efficacy and durability of this procedure. The study included patients who had undergone continuous flow left ventricular assist device implantation. The patients were divided into 2 groups, those who did not require any aortic procedure because the valve was competent and those who underwent central aortic valve closure for mild or greater aortic regurgitation. The clinical endpoints were mortality, progression or recurrence of aortic insufficiency, and reoperation for aortic valve pathologic features. Aortic insufficiency was measured qualitatively from mild to severe on a scale of 0 to 5. A total of 123 patients received continuous flow left ventricular assist devices from February 2007 to August 2011. Of those, 18 (15%) underwent central aortic valve closure at left ventricular assist device implantation because of significant aortic insufficiency (1.8 ± 1.4) and 105 who did not (competent aortic valve, 0.15 ± 0.43; P < .01). At follow-up (median, 312 days; range, 0-1429 days), the mean aortic insufficiency score remained low for the patients with central aortic valve closure (0.27 ± 0.46) in contrast to those without central aortic valve closure who experienced aortic insufficiency progression (0.78 ± 0.89; P = .02). In addition, the proportion of patients with more than mild aortic insufficiency was significantly less in the central aortic valve closure group (0% vs 18%; P = .05). The patients in the central aortic valve closure group were significantly older and had a greater incidence of renal failure at baseline. The 30-day mortality was greater in the central aortic valve closure group, but the late survival was similar between the 2 groups. No reoperations were required for recurrent aortic insufficiency. The results of our study have shown that repair of aortic insufficiency with a simple central coaptation stitch is effective and durable in left ventricular assist device-supported patients, with follow-up extending into 2 years. Although aortic insufficiency progressed over time in those with minimal native valve regurgitation initially, no such progression was noted in those with central aortic valve closure. Additional investigation is needed to evaluate whether prophylactic central aortic valve closure should be performed at left ventricular assist device implantation to avoid problematic aortic regurgitation developing over time, in particular in patients undergoing left ventricular assist device implantation for life-long (destination therapy) support. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

The Flatstent versus the conventional umbrella devices in the percutaneous closure of patent foramen ovale.

PubMed

Aral, Mert; Mullen, Michael

2015-05-01

Patent foramen ovale (PFO) has been associated with paradoxical embolism leading to stroke/transient ischemic attack, migraine, and neurological decompression sickness. In search for the optimal device that would achieve effective clinical closure with minimal complications, a better device selection based on PFO anatomy and improvements in device design is needed. The Flatstent is a new device designed to treat the highly prevalent long-tunnel PFOs from within, minimizing the amount of material left behind in an attempt to reduce device-related complications. The objective is to compare the safety and efficacy of the novel Flatstent versus the conventional umbrella devices in the transcatheter closure of PFO in a nonrandomized, retrospective, single-center study. Between March 2010 and March 2013, 88 patients underwent PFO closure at The Heart Hospital, London with either the novel Flatstent or one of the four conventionally used umbrella devices (GORE Helex Septal Occluder, Occlutech Figulla Flex, Biostar Septal Occluder, and Amplatzer PFO Occluder) depending on their PFO anatomy. Patients were then evaluated with contrast transthoracic echocardiography (TTE) and/or transoesophageal echocardiography (TOE) at 6 weeks and 1 year after the procedure. The residual shunt and complication rates between the Flatstent and umbrella devices were compared. The Flatstent was used in 27 patients (30.7%), whereas 61 patients (69.3%) received one of the four umbrella devices. Primary efficacy point of clinical closure defined as grade 0 or grade 1; residual shunt was achieved in 81.3% in the Flatstent cohort and 80.3% in the umbrella device group at 6 weeks follow-up. At 1 year, the clinical closure rates reached 92.6 and 91.8%. There were two device embolizations, one in each cohort during the immediate postoperative period (<24 hrs), with successful retrieval. One patient in the umbrella device group developed transient atrial fibrillation, which was controlled medically. Event recurrence rate was 0% at 1 year. No difference was found in closure or complication rates between the Flatstent and the umbrella devices. With appropriate preassessment of the PFO anatomy, the Flatstent works as a safe and effective method of treating the PFO from within the tunnel, especially in those with long-tunnel PFOs. Longer follow-up is needed to establish superiority. © 2014 Wiley Periodicals, Inc.

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2012 CFR

2012-04-01

... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2013 CFR

2013-04-01

... OF THE TREASURY ALCOHOL LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2010 CFR

2010-04-01

... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2014 CFR

2014-04-01

... OF THE TREASURY ALCOHOL LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2011 CFR

2011-04-01

... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

Transcatheter Closure of Patent Foramen Ovale: Devices and Technique.

PubMed

Price, Matthew J

2017-10-01

Transcatheter closure of a patent foramen ovale (PFO) reduces the risk of recurrent cryptogenic stroke compared with medical therapy. PFO closure is a prophylactic procedure, and will not provide the patient with symptomatic improvement, except in cases of hypoxemia due to right-to-left shunt or possibly migraine headaches. Therefore, appropriate patient selection is critical, and procedural safety is paramount. Herein, we review key characteristics of the devices currently available for transcatheter PFO closure within the United States, and highlight key technical aspects of the PFO closure procedure that will maximize procedural success. Copyright © 2017 Elsevier Inc. All rights reserved.

Transapical access closure: the TA PLUG device†

PubMed Central

Brinks, Henriette; Nietlispach, Fabian; Göber, Volkhard; Englberger, Lars; Wenaweser, Peter; Meier, Bernhard; Carrel, Thierry; Huber, Christoph

2013-01-01

OBJECTIVES Percutaneous closure of the transapical (TA) access site for large-calibre devices is an unsolved issue. We report the first experimental data on the TA PLUG device for true-percutaneous closure following large apical access for transcatheter aortic valve implantation. METHODS The TA PLUG, a self-sealing full-core closure device, was implanted in an acute animal study in six pigs (60.2 ± 0.7 kg). All the pigs received 100 IU/kg of heparin. The targeted activated clotting time was left to normalize spontaneously. After accessing the left ventricular apex with a 39 French introducer, the closure plug device was delivered with a 33 French over-the-wire system under fluoroscopic guidance into the apex. Time to full haemostasis as well as rate of bleeding was recorded. Self-anchoring properties were assessed by haemodynamic push stress under adrenalin challenge. An additional feasibility study was conducted in four pigs (58.4 ± 1.1 kg) with full surgical exposure of the apex, and assessed device anchoring by pull-force measurements with 0.5 Newton (N) increments. All the animals were electively sacrified. Post-mortem analysis of the heart was performed and the renal embolic index assessed. RESULTS Of six apical closure devices, five were correctly inserted and fully deployed at the first attempt. One became blocked in the delivery system and was placed successfully at the second attempt. In all the animals, complete haemostasis was immediate and no leak was recorded during the 5-h observation period. Neither leak nor any device dislodgement was observed under haemodynamic push stress with repeated left ventricular peak pressure of up to 220 mmHg. In the feasibility study assessing pull-stressing, device migration occurred at a force of 3.3 ± 0.5 N corresponding to 247.5 mmHg. Post-mortem analyses confirmed full expansion of all devices at the intended target. No macroscopic damage was identified at the surrounding myocardium. The renal embolic index was zero. CONCLUSIONS True-percutaneous left ventricular apex closure following large access is feasible with the self-sealing TA PLUG. The device allows for immediate haemostasis and a reliable anchoring in the acute animal setting. This is the first report of a true-percutaneous closure for large-calibre transcatheter aortic valve implantation access. PMID:23842759

Intraoperative Transesophageal Echocardiography and Right Ventricular Failure After Left Ventricular Assist Device Implantation.

PubMed

Silverton, Natalie A; Patel, Ravi; Zimmerman, Josh; Ma, Jianing; Stoddard, Greg; Selzman, Craig; Morrissey, Candice K

2018-02-15

To determine whether intraoperative measures of right ventricular (RV) function using transesophageal echocardiography are associated with subsequent RV failure after left ventricular assist device (LVAD) implantation. Retrospective, nonrandomized, observational study. Single tertiary-level, university-affiliated hospital. The study comprised 100 patients with systolic heart failure undergoing elective LVAD implantation. Transesophageal echocardiographic images before and after cardiopulmonary bypass were analyzed to quantify RV function using tricuspid annular plane systolic excursion (TAPSE), tricuspid annular systolic velocity (S'), fractional area change (FAC), RV global longitudinal strain, and RV free wall strain. A chart review was performed to determine which patients subsequently developed RV failure (right ventricular assist device placement or prolonged inotrope requirement ≥14 days). Nineteen patients (19%) subsequently developed RV failure. Postbypass FAC was the only measure of RV function that distinguished between the RV failure and non-RV failure groups (21.2% v 26.5%; p = 0.04). The sensitivity, specificity, and area under the curve of an abnormal RV FAC (<35%) for RV failure after LVAD implantation were 84%, 20%, and 0.52, respectively. No other intraoperative measure of RV function was associated with subsequent RV failure. RV failure increased ventilator time, intensive care unit and hospital length of stay, and mortality. Intraoperative measures of RV function such as tricuspid annular plane systolic excursion, tricuspid annular systolic velocity, and RV strain were not associated with RV failure after LVAD implantation. Decreased postbypass FAC was significantly associated with RV failure but showed poor discrimination. Copyright © 2018 Elsevier Inc. All rights reserved.

Double emulsions from a capillary array injection microfluidic device.

PubMed

Shang, Luoran; Cheng, Yao; Wang, Jie; Ding, Haibo; Rong, Fei; Zhao, Yuanjin; Gu, Zhongze

2014-09-21

A facile microfluidic device was developed by inserting an annular capillary array into a collection channel for single-step emulsification of double emulsions. By inserting multiple inner-phase solutions into the capillary array, multicomponent double emulsions or microcapsules with inner droplets of different content could also be obtained from the device.

Vascular closure devices in stroke patients receiving tissue plasminogen activator: A retrospective analysis from an academic tertiary medical center and a teaching community hospital stroke database.

PubMed

Patil, Mangaladevi S; Jayaraman, Mahesh V; Ahn, Sun H

2017-06-01

To determine the safety and effectiveness of vascular closure devices in prevention of access site complications in acute stroke patient receiving intravenous (IV) and/or intra-arterial (IA) IV tissue plasminogen activator (tPA). All patients with acute stroke onset treated with IV and/or IA tPA closed with vascular closure device and adult age (>18 years) were identified from an academic tertiary medical center and a teaching community hospital stroke database for 9 years (from March 2005 to June 2014). A total of 69 patients were included in the study. The mean age was 68.86±16.70 years and 49.2% female. All accesses were under fluoroscopic guidance into the right common femoral artery. We observed a 5.8% complication rate in patients receiving IV and/or IA tPA closed with vascular closure device. Access site complications included 3 cases of hematoma and 1 case of residual oozing. One patient required transfusion due to access site hematoma. Three patients were on aspirin and heparin and 1 was on no prior anticoagulation. Vascular closure device access site hemorrhagic complication rate in those receiving IV and/or IA tPA is low and similar to reported rates in those not receiving thrombolytic therapy. Vascular closure device use in patients receiving thrombolytic therapy is safe and effectively achieves hemostasis. Copyright © 2017 Elsevier B.V. All rights reserved.

Transcatheter closure of patent ductus arteriosus in children weighing 10 kg or less: Initial experience at Sohag University Hospital.

PubMed

Ali, Safaa; El Sisi, Amel

2016-04-01

To assess the challenges, feasibility, and efficacy of device closure of patent ductus arteriosus (PDA) in small children weighing ⩽10 kg for different types of devices used in an initial experience at Sohag University hospital. Between March 2011 and September 2014, 91 patients with PDA underwent transcatheter closure in our institute, among whom 54 weighed ⩽10 kg. All of these patients underwent transcatheter closure of PDA using either a Cook Detachable Coil, PFM Nit-Occlud, or Amplatzer duct occluder. A retrospective review of the treatment results and adverse events was performed. Successful device placement was achieved in 53/54 small children (98.1%). The median minimum PDA diameter was 2.4 mm [interquartile range (IQR, 1.8-3.5 mm), median weight 8 kg (IQR, 7-10 kg), and median age 10 months (IQR, 8-17 months)]. Mild aortic obstruction occurred in one case (1.9%), as the device became displaced towards the aorta after release. The device embolized in one case (1.9%) and no retrieval attempt was made. Five cases (9.3%) had minor vascular complications. With the current availability of devices for PDA closure, transcatheter closure of PDA is considered safe and efficacious in small children weighing ⩽10 kg with good mid-term outcome. The procedure had a low rate of high-severity adverse events even with the initial experience of the catheterization laboratory.

Closure of Patent Foramen Ovale versus Medical Therapy after Cryptogenic Stroke: Meta-Analysis of Five Randomized Controlled Trials with 3440 Patients

PubMed Central

Sá, Michel Pompeu Barros Oliveira; de Oliveira Neto, Luiz de Albuquerque Pereira; do Nascimento, Gabriella Caroline Sales; Vieira, Erik Everton da Silva; Martins, Gabriel Lopes; Rodrigues, Karine Coelho; Nascimento, Giulia Cioffi; de Menezes, Alexandre Motta; Lins, Ricardo Felipe de Albuquerque; Silva, Frederico Pires Vasconcelos; Lima, Ricardo Carvalho

2018-01-01

Objective We aimed to determine whether patent foramen ovale closure reduces the risk of stroke, also assessing some safety outcomes. Introduction The clinical benefit of closing a patent foramen ovale after a cryptogenic stroke has been an open question for several decades, so that it is necessary to review the current state of published medical data in this regard. Methods MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LI-LACS, Google Scholar and reference lists of relevant articles were searched for randomized controlled trials that reported any of the following outcomes: stroke, death, major bleeding or atrial fibrillation. Five studies fulfilled our eligibility criteria and included 3440 patients (1829 for patent foramen ovale closure and 1611 for medical therapy). Results The risk ratio (RR) for stroke in the "device closure" group compared with the "medical therapy" showed a statistically significant difference between the groups, favouring the "device closure" group (RR 0.400; 95% CI 0.183-0.873, P=0.021). There was no statistically significant difference between the groups regarding the safety outcomes death and major bleeding, but we observed an increase in the risk of atrial fibrillation in the "device closure group (RR 4.000; 95% CI 2.262-7.092, P<0.001). We also observed that the larger the proportion of effective closure, the lower the risk of stroke. Conclusion This meta-analysis found that stroke rates are lower with percutaneously implanted device closure than with medical therapy alone, being these rates modulated by the rates of effective closure. PMID:29617507

Remotely operated pipe connector

DOEpatents

Josefiak, Leonard J.; Cramer, Charles E.

1988-01-01

An apparatus for remotely assembling and disassembling a Graylock type coctor between a pipe and a closure for the pipe includes a base and a receptacle on the base for the closure. The pipe is moved into position vertically above the closure by a suitable positioning device such that the flange on the pipe is immediately adjacent and concentric with the flange on the closure. A moving device then moves two semicircular collars from a position free of the closure to a position such that the interior cam groove of each collar contacts the two flanges. Finally, a tensioning device automatically allows remote tightening and loosening of a nut and bolt assembly on each side of the collar to cause a seal ring located between the flanges to be compressed and to seal the closure. Release of the pipe and the connector is accomplished in the reverse order. Preferably, the nut and bolt assembly includes an elongate shaft portion on which a removable sleeve is located.

AMPLATZER versus Figulla occluder for transcatheter patent foramen ovale closure.

PubMed

Trabattoni, Daniela; Gaspardone, Achille; Sgueglia, Gregory A; Fabbiocchi, Franco; Gioffrè, Gaetano; Montorsi, Piero; Calligaris, Giuseppe; Iamele, Maria; De Santis, Antonella; Bartorelli, Antonio L

2017-04-20

The aim of this observational study was to compare acute and 12-month results of percutaneous closure of patent foramen ovale (PFO) with two occluder devices. Between June 2007 and October 2014, 406 consecutive patients (48.1±13.3 years, 243 women) underwent percutaneous PFO closure with either the AMPLATZER (n=179) or the Figulla (n=227) device after a stroke or a transient ischaemic attack ascribed to the PFO. A right-to-left shunt grade >1 was previously detected in all patients and atrial septal aneurysm was present in 111 (27.5%) patients. Patients were followed up with a contrast transthoracic echocardiogram and clinically at 24 hours, six months, and 12 months after the procedure. A high procedural success was observed in both groups. Despite a trend towards a higher incidence of acute residual shunt immediately after device deployment among Figulla occluder patients, a residual grade ≥2 right-to-left shunt was observed in 4.5% of patients, independently of the device used for PFO closure. The only difference reported after Figulla device implantation was a lower rate of supraventricular arrhythmias (9% vs. 17%, p=0.02). According to this two-centre study, PFO closure appears safe and effective with the Figulla occluder as well as with the AMPLATZER device.

CIRSE Vascular Closure Device Registry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reekers, Jim A., E-mail: j.a.reekers@amc.uva.nl; Mueller-Huelsbeck, Stefan; Libicher, Martin

2011-02-15

Purpose: Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods: The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results: Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0-14.5] for antegrade access and 1.8% (95% CI 1.1-2.9) for retrograde access (Pmore » = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only <0.5% of patients. Postdeployment bleeding occurred in 6.4%, and most these (51.5%) could be managed with light manual compression. During follow-up, other device-related complications were reported in 1.3%: seven false aneurysms, three hematoma >5.9 cm, and two vessel occlusions. Conclusion: The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters.« less

CIRSE Vascular Closure Device Registry

PubMed Central

Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria

2010-01-01

Purpose Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0–14.5] for antegrade access and 1.8% (95% CI 1.1–2.9) for retrograde access (P = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only <0.5% of patients. Postdeployment bleeding occurred in 6.4%, and most these (51.5%) could be managed with light manual compression. During follow-up, other device-related complications were reported in 1.3%: seven false aneurysms, three hematoma >5.9 cm, and two vessel occlusions. Conclusion The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters. PMID:20981425

Annular resonators for high-power chemical lasers

NASA Astrophysics Data System (ADS)

Wade, Richard C.

1993-08-01

Resonators capable of extracting highly coherent energy from DF and HF chemical laser annular gain media have been under investigation for weapon application since 1974. This survey article traces the background of interest in these devices, describes the various concepts that have been experimentally and analytically investigated, and discusses the issues associated with their operation. From the discussion of issues, preferred concepts are selected. Applicability of these concepts to high-power operation is addressed through discussions of past and ongoing high-power demonstration programs and the issues facing their application to weapon sized devices capable of strategic and tactical missions such as ballistic missile defense (BMD), theater missile defense (TMD), and anti satellite (ASAT).

Safety of Percutaneous Patent Ductus Arteriosus Closure: An Unselected Multicenter Population Experience

PubMed Central

El‐Said, Howaida G.; Bratincsak, Andras; Foerster, Susan R.; Murphy, Joshua J.; Vincent, Julie; Holzer, Ralf; Porras, Diego; Moore, John; Bergersen, Lisa

2013-01-01

Background The technique and safety of transcatheter patent ductus arteriosus (PDA) closure have evolved during the past 20 years. We sought to report a multicenter experience of PDA closure with a focus on the rate of adverse events (AE) and a review of institutional practice differences. Methods and Results Outcome data on transcatheter PDA closure were collected at 8 centers prospectively using a multicenter registry (Congenital Cardiac Catheterization Project on Outcome Registry). Between February 2007 and June 2010, 496 PDA closures were recorded using a device in 338 (68%) or coils in 158 (32%). Most patients had an isolated PDA (90%). Fifty percent of patients were between 6 months and 3 years old, with only 40 patients (8%) <6 months old. Median minimum PDA diameter was 2.5 mm (range 1 to 12 mm; IQR 2 to 3 mm) for device closure and 1 mm (range 0.5 to 6 mm; IQR 1 to 2 mm) for coil closure (P<0.001). A device rather than coil was used in patients <3 years, weight <11 kg, and with a PDA minimum diameter >2 mm (all P<0.001). Three of 8 centers exclusively used a device for PDAs with a diameter >1.5 mm. In 9% of cases (n=46), an AE occurred; however, only 11 (2%) were classified as high severity. Younger age was associated with a higher AE rate. Coil‐related AEs were more common than device‐related AEs (10% versus 2%, P<0.001). Conclusions PDA closure in the present era has a very low rate of complications, although these are higher in younger children. Technical intervention‐related events were more common in coil procedures compared with device procedures. For PDAs ≤2.5 mm in diameter, institutional differences in preference for device versus coil exist. PMID:24284214

The Annular Suspension and Pointing (ASP) system for space experiments and predicted pointing accuracies

NASA Technical Reports Server (NTRS)

Anderson, W. W.; Joshi, S. M.

1975-01-01

An annular suspension and pointing system consisting of pointing assemblies for coarse and vernier pointing is described. The first assembly is attached to a carrier spacecraft (e.g., the space shuttle) and consists of an azimuth gimbal and an elevation gimbal which provide 'coarse' pointing. The second or vernier pointing assembly is made up of magnetic actuators of suspension and fine pointing, roll motor segments, and an instrument or experiment mounting plate around which is attached a continuous annular rim similar to that used in the annular momentum control device. The rim provides appropriate magnetic circuits for the actuators and the roll motor segments for any instrument roll position. The results of a study to determine the pointing accuracy of the system in the presence of crew motion disturbances are presented. Typical 3 sigma worst-case errors are found to be of the order of 0.001 arc-second.

Hybrid multiphase CFD simulation for liquid-liquid interfacial area prediction in annular centrifugal contactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wardle, K.E.

2013-07-01

Liquid-liquid contacting equipment used in solvent extraction processes has the dual purpose of mixing and separating two immiscible fluids. Consequently, such devices inherently encompass a wide variety of multiphase flow regimes. A hybrid multiphase computational fluid dynamics (CFD) solver which combines the Eulerian multi-fluid method with VOF (volume of fluid) sharp interface capturing has been developed for application to annular centrifugal contactors. This solver has been extended to enable prediction of mean droplet size and liquid-liquid interfacial area through a single moment population balance method. Simulations of liquid-liquid mixing in a simplified geometry and a model annular centrifugal contactor aremore » reported with droplet breakup/coalescence models being calibrated versus available experimental data. Quantitative comparison is made for two different housing vane geometries and it is found that the predicted droplet size is significantly smaller for vane geometries which result in higher annular liquid holdup.« less

Left Atrial Appendage Closure for Stroke Prevention: Devices, Techniques, and Efficacy.

PubMed

Iskandar, Sandia; Vacek, James; Lavu, Madhav; Lakkireddy, Dhanunjaya

2016-05-01

Left atrial appendage closure can be performed either surgically or percutaneously. Surgical approaches include direct suture, excision and suture, stapling, and clipping. Percutaneous approaches include endocardial, epicardial, and hybrid endocardial-epicardial techniques. Left atrial appendage anatomy is highly variable and complex; therefore, preprocedural imaging is crucial to determine device selection and sizing, which contribute to procedural success and reduction of complications. Currently, the WATCHMAN is the only device that is approved for left atrial appendage closure in the United States. Copyright © 2016 Elsevier Inc. All rights reserved.

Cooling arrangement for a superconducting coil

DOEpatents

Herd, K.G.; Laskaris, E.T.

1998-06-30

A superconducting device is disclosed, such as a superconducting rotor for a generator or motor. A vacuum enclosure has an interior wall surrounding a cavity containing a vacuum. A superconductive coil is placed in the cavity. A generally-annularly-arranged, thermally-conductive sheet has an inward-facing surface contacting generally the entire outward-facing surface of the superconductive coil. A generally-annularly-arranged coolant tube contains a cryogenic fluid and contacts a generally-circumferential portion of the outward-facing surface of the sheet. A generally-annularly-arranged, thermally-insulative coil overwrap generally circumferentially surrounds the sheet. The coolant tube and the inward-facing surface of the coil overwrap together contact generally the entire outward-facing surface of the sheet. 3 figs.

Sweat collection capsule

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Delaplaine, R. W. (Inventor)

1980-01-01

A sweat collection capsule permitting quantitative collection of sweat is described. The device consists of a frame held immobile on the skin, a closure secured to the frame and absorbent material located next to the skin in a cavity formed by the frame and the closure. The absorbent material may be removed from the device by removing the closure from the frame while the frame is held immobile on the skin.

Safety and feasibility of intra-operative device closure of atrial septal defect with transthoracic minimal invasion.

PubMed

Chen, Qiang; Cao, Hua; Zhang, Gui-Can; Chen, Liang-Wan; Chen, Dao-Zhong

2012-01-01

The study aims to evaluate the safety and feasibility of intra-operative device closure of atrial septal defect with transthoracic minimal invasion. From May 2006 to June 2009, 252 patients with secundum-type atrial septal defect closure were enrolled in our institution. The patients were divided into two groups, with 182 patients in group I with intra-operative device closure and 72 in group II with surgical closure. In group I, the patients' age ranged from 3 months to 62 years (mean±standard deviation, 19.0±16.7 years). This approach involved a transthoracic minimal invasion that was performed after full evaluation of the atrial septal defect by transthoracic echocardiography, deploying the device through the delivery sheath to occlude the atrial septal defect. In group I, 180 patients were occluded successfully under this approach. The size of the occluder device implanted ranged from 6 to 48 mm. Minor complications occurred, which included transient arrhythmias (n=23) and pleural effusion (n=15). Two patients with postoperative cardiac arrest were successfully cardiopulmonary resuscitated. Another two patients with occluder dislodged back into the right atrium were turned to surgical repair with cardiopulmonary bypass on the postoperative day. In group II, all patients were occluded successfully, and almost all patients needed blood transfusion and suffered from various minor complications. All discharged patients were followed up for 1-5 years. During this period, we found no recurrence, no thrombosis, even no device failure. In our comparative studies, group II had significantly longer intensive care unit (ICU) stay and hospital stay than group I (p<0.05). The cost for group I was less than group II (p<0.05). Intra-operative device closure of atrial septal defect with transthoracic minimal invasion is a safe and feasible technique. It had the advantages of cost savings, yielding better cosmetic results, and leaving less trauma than surgical closure.

Intraoperative device closure of atrial septal defects with inferior vena cava rim deficiency: a safe alternative to surgical repair.

PubMed

Chen, Qiang; Chen, Liang-Wan; Cao, Hua; Zhang, Gui-Can; Chen, Dao-Zhong; Zhang, Hui

2011-03-01

Our objective was to evaluate the safety and feasibility of intraoperative device closure of atrial septal defects with inferior vena cava rim deficiency. From January 2005 to December 2008, we enrolled 65 patients who had a secundum atrial septal defect with inferior vena cava rim deficiency closure in our institution. Patients were divided into 2 groups: 35 patients in group I underwent intraoperative device closure with a right lateral minithoracotomy and 30 in group II underwent open cardiac repair with a right lateral thoracotomy and cardiopulmonary bypass. Intraoperative device closure involved a minimal intercostal incision that was performed after full evaluation of the atrial septal defect by transthoracic echocardiography and the insertion of the device through the delivery sheath to occlude the atrial septal defect. The procedure was successful in all patients. In group I, the diameter of the atrial septal defect ranged from 30 to 44 mm (mean, 35.3 ± 3.9 mm), and the size of the implanted occluder ranged from 34 to 48 mm (mean, 40 ± 2.1 mm). The total occlusion rate was 82.9% immediately after the operation, 97.1% at 3 months, and 100% at 12 and 24 months of follow-up. In group II, all patients had successful closure. A follow-up period of 12 to 24 months was obtained in both groups. During the follow-up, there was no recurrence, thrombosis, or device failure. In our comparative studies, group II had significantly longer operative time, intensive care unit stay, and hospital stay than group I (P < .001). The cost of group I was less than that of group II (20,450.9 ± 840.8 RMB vs 25,884.9 ± 701.8; P < .001). Intraoperative device closure of atrial septal defects with inferior vena cava rim deficiency is a safe and feasible technique. It has the advantages of cost savings, cosmetic results, and less trauma than surgical closure. Early and midterm results are encouraging. Crown Copyright © 2011. Published by Mosby, Inc. All rights reserved.

Device closure of secundum atrial septal defect's and the risk of cardiac erosion.

PubMed

Thomson, J D R; Qureshi, S A

2015-12-01

Cardiac erosion related to transcatheter atrial septal defect closure devices is of increasing concern. Erosion is reported to have occurred with most of currently available occluder devices. Perhaps due to the very large number of implants worldwide, the Amplatzer (St Jude) occluder is associated with the majority of cardiac erosion events reported in the literature. Best current estimates of the incidence of erosion with the St Jude device are between one and three cases per 1000 implants. Most events occur early after implantation and it is rare, although not unheard of, for events to occur after a year following device insertion. It is important that those involved with closure programmes are vigilant for the problem, because device-related erosion is associated with a significant mortality risk. Despite considerable debate, the risk factors (either patient or device) for erosion remain unclear and require further investigation. Currently available data sets have focussed largely on erosion cohorts and are unable to place these cases in appropriate context with non-erosion closure cases. What is certain is that programmes implanting these devices must take care to implant appropriately sized devices and have in place plans to ensure that patients are both well informed and can access help and advice in the event of developing symptoms.

Design, construction and testing of annular diffusers for high speed civil transportation combustor applications

NASA Technical Reports Server (NTRS)

Okhio, Cyril B.

1995-01-01

A theoretical and an experimental design study of subsonic flow through curved-wall annular diffusers is being carried out in order to establish the most pertinent design parameters for such devices and the implications of their application in the design of engine components in the aerospace industries. This investigation consists of solving numerically the full Navier Stokes and Continuity equations for the time-mean flow. Various models of turbulence are being evaluated for adoption throughout the study and comparisons would be made with experimental data where they exist. Assessment of diffuser performance based on the dissipated mechanical energy would also be made. The experimental work involves the application of Computer Aided Design software tool to the development of a suitable annular diffuser geometry and the subsequent downloading of such data to a CNC machine at Central State University. The results of the investigations are expected to indicate that more cost effective component design of such devices as effective component design of such devices as diffusers which normally contain complex flows can still be achieved. In this regard a review paper was accepted and presented at the First International Conference on High Speed Civil Transportation Research held at North Carolina A&T in December of 1994.

Retrograde transcatheter device closure of a complex paravalvular leak after bioprosthetic pulmonary valve replacement in a pediatric patient.

PubMed

Chikkabyrappa, Sathish; Mosca, Ralph S; McElhinney, Doff B

2016-06-01

We report a case of retrograde transcatheter device closure of a complex paravalvular leak (PVL) after bioprosthetic pulmonary valve replacement (PVR) in a 13-year-old patient with congenital pulmonary valve stenosis. There are prior reports of pulmonary PVL closure after PVR in adults (Seery and Slack, Congenit Heart Dis 2014;9:E19-F22), but indications for and technical considerations in PVL closure after bioprosthetic PVR, particularly in children, are not well defined. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Percutaneous device closure of atrial septal defect results in very early and sustained changes of right and left heart function.

PubMed

Monfredi, Oliver; Luckie, Matthew; Mirjafari, Hoda; Willard, Terence; Buckley, Helen; Griffiths, Linda; Clarke, Bernard; Mahadevan, Vaikom S

2013-08-20

To investigate the echocardiographic effects of percutaneous closure of secundum atrial septal defect (ASD) in adults and assess which pre-closure parameters predict good response to closure. ASD is a common congenital heart disease often undiscovered until adulthood. ASD closure has been revolutionized by the use of percutaneous devices. The effects of these procedures on echocardiographic parameters are not well characterized. Patients undergoing percutaneous device closure of ASD between June 2007 and June 2009 had 3 sequential echocardiograms reviewed: pre-procedure, immediate post-procedure (24 hours) and 6-8 weeks post-procedure. Significant changes from baseline were investigated using paired t-test/1-way ANOVA. Pearson correlation (2-tailed) tests were used to categorize patients as 'good responders' to closure in terms of selected parameters. 129 echocardiograms in 43 consecutive patients were included. Remodeling of both ventricles occurred immediately following ASD closure and was sustained. Right ventricular (RV) diameter in diastole decreased by 13.5% and 19.3% compared to baseline at 24 hours and 6-8 weeks post-closure, respectively (p<0.05); Left ventricular (LV) diameter in diastole increased by 8.5% and 15.6%, respectively (p<0.05). Functional parameters of the RV also demonstrated early and sustained decreases (TAPSE decreased by 8.3% and 17% compared to baseline at 24 hours and 6-8 weeks post-closure, respectively (p<0.05)). Smaller RV baseline diameter appeared to predict good response to closure. Percutaneous ASD closure has immediate, sustained benefits on multiple echocardiographic parameters. Good responders have smaller RV at baseline, suggesting early closure is preferable. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Angle closure glaucoma in congenital ectropion uvea.

PubMed

Wang, Grace M; Thuente, Daniel; Bohnsack, Brenda L

2018-06-01

Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months) and required additional surgery (cycloablation or trabeculectomy). Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control.

Changes in Mitral Annular Geometry after Aortic Valve Replacement: A Three-Dimensional Transesophageal Echocardiographic Study

PubMed Central

Mahmood, Feroze; Warraich, Haider J.; Gorman, Joseph H.; Gorman, Robert C.; Chen, Tzong-Huei; Panzica, Peter; Maslow, Andrew; Khabbaz, Kamal

2014-01-01

Background and aim of the study Intraoperative real-time three-dimensional transesophageal echocardiography (RT-3D TEE) was used to examine the geometric changes that occur in the mitral annulus immediately after aortic valve replacement (AVR). Methods A total of 35 patients undergoing elective surgical AVR under cardiopulmonary bypass was enrolled in the study. Intraoperative RT-3D TEE was used prospectively to acquire volumetric echocardiographic datasets immediately before and after AVR. The 3D echocardiographic data were analyzed offline using TomTec® Mitral Valve Assessment software to assess changes in specific mitral annular geometric parameters. Results Datasets were successfully acquired and analyzed for all patients. A significant reduction was noted in the mitral annular area (-16.3%, p <0.001), circumference (-8.9% p <0.001) and the anteroposterior (-6.3%, p = 0.019) and anterolateral-posteromedial (-10.5%, p <0.001) diameters. A greater reduction was noted in the anterior annulus length compared to the posterior annulus length (10.5% versus 62%, p <0.05) after AVR. No significant change was seen in the non-planarity angle, coaptation depth, and closure line length. During the period of data acquisition before and after AVR, no significant change was noted in the central venous pressure or left ventricular end-diastolic diameter. Conclusion The mitral annulus undergoes significant geometric changes immediately after AVR Notably, a 16.3% reduction was observed in the mitral annular area. The anterior annulus underwent a greater reduction in length compared to the posterior annulus, which suggested the existence of a mechanical compression by the prosthetic valve. PMID:23409347

Self-expanding nanoplatinum-coated nitinol devices for atrial septal defect and patent ductus arteriosus closure: a swine model.

PubMed

Lertsapcharoen, Pornthep; Khongphatthanayothin, Apichai; La-orkhun, Vidhavas; Supachokchaiwattana, Pentip; Charoonrut, Phingphol

2006-01-01

Our purpose was to evaluate self-expanding nanoplatinum-coated nitinol devices for transcatheter closure of atrial septal defects and patent ductus arteriosus in a swine model. The devices were braided from platinum-activated nitinol wires and filled with polyester to enhance thrombogenicity. The platinum activation of the nitinol wires was carried out with the help of Nanofusion technology. The coating of platinum covers the exposed surface of the nitinol wires and prevents the release of nickel into the blood stream after the implantation of the device but does not affect its shape memory, which makes the device self-expanding after it is loaded from the catheter. Atrial septal defects were created in 12 piglets by balloon dilation of the patent foramen ovale. The size of the device was selected on the basis of the diameter of the balloon and the size of the defect, measured by transthoracic echocardiography. The devices were successfully deployed in all 12 piglets under fluoroscopic study. Transthoracic color Doppler echocardiograms showed complete closure of the atrial septal defect within 15 minutes of device implantation. Twelve patent ductus arteriosus closure devices were deployed in the right or left subclavian arteries in 10 piglets. Angiograms showed complete occlusion of the subclavian arteries within a few minutes of device deployment. In the atrial septal defect cases, the autopsy findings showed complete organizing fibrin thrombus formation and complete neo-endothelialization on the outer surface of the devices within one week and six weeks of implantation, respectively. The use of self-expanding nanoplatinum-coated nitinol devices for the transcatheter closure of atrial septal defects and patent ductus arteriosus is feasible. The excellent occlusion result and complete neo-endothelialization of the devices in the swine model is an indication of the potential of these devices in human application.

Transcatheter closure of patent ductus arteriosus in children weighing 10 kg or less: Initial experience at Sohag University Hospital

PubMed Central

Ali, Safaa; El Sisi, Amel

2015-01-01

Aim To assess the challenges, feasibility, and efficacy of device closure of patent ductus arteriosus (PDA) in small children weighing ⩽10 kg for different types of devices used in an initial experience at Sohag University hospital. Methods Between March 2011 and September 2014, 91 patients with PDA underwent transcatheter closure in our institute, among whom 54 weighed ⩽10 kg. All of these patients underwent transcatheter closure of PDA using either a Cook Detachable Coil, PFM Nit-Occlud, or Amplatzer duct occluder. A retrospective review of the treatment results and adverse events was performed. Results Successful device placement was achieved in 53/54 small children (98.1%). The median minimum PDA diameter was 2.4 mm [interquartile range (IQR, 1.8–3.5 mm), median weight 8 kg (IQR, 7–10 kg), and median age 10 months (IQR, 8–17 months)]. Mild aortic obstruction occurred in one case (1.9%), as the device became displaced towards the aorta after release. The device embolized in one case (1.9%) and no retrieval attempt was made. Five cases (9.3%) had minor vascular complications. Conclusion With the current availability of devices for PDA closure, transcatheter closure of PDA is considered safe and efficacious in small children weighing ⩽10 kg with good mid-term outcome. The procedure had a low rate of high-severity adverse events even with the initial experience of the catheterization laboratory. PMID:27053899

Fabrication and evaluation of variable focus and large deformation plano-convex microlens based on non-ionic poly(vinyl chloride)/dibutyl adipate gels

NASA Astrophysics Data System (ADS)

Kim, Sang-Youn; Yeo, Myoung; Shin, Eun-Jae; Park, Won-Hyeong; Jang, Jong-Seok; Nam, Byeong-Uk; Bae, Jin Woo

2015-11-01

In this paper, we propose a variable focus microlens module based on a transparent, electroactive, and non-ionic PVC/DBA gel. A non-ionic PVC/DBA (nPVC) gel on an ITO glass was confined beneath a rigid annular electrode, and applied pressure squeezed a bulge of the nPVC gel into the annular electrode, resulting in a hemispherical plano-convex nPVC gel microlens. The proposed nPVC gel microlens was analyzed and optimized. When voltage is applied to the circular perimeter (the annular electrode) of this fabricated microlens, electrically induced creep deformation of the nPVC gel occurs, changing its optical focal length. The focal length remarkably increases from 3.8 mm up to 14.3 mm with increasing applied voltages from 300 V to 800 V. Due to its compact, transparent, and electroactive characteristics, the proposed nPVC gel microlens can be easily inserted into small consumer electronic devices, such as digital cameras, camcorders, cell phones, and other portable optical devices.

Self-testing security sensor for monitoring closure of vault doors and the like

DOEpatents

Cawthorne, Duane C.

1997-05-27

A self-testing device is provided for a monitoring system for monitoring whether a closure member such as a door or window is closed. The monitoring system includes a switch unit mounted on the frame of the closure member being monitored and including magnetically biased switches connected in one or more electrical monitoring circuits, and a door magnet unit mounted on the closure member being monitored. The door magnet includes one or more permanent magnets that produce a magnetic field which, when the closure member is closed, cause said switches to assume a first state. When the closure member is opened, the switches switch to a second, alarm state. The self-testing device is electrically controllable from a remote location and produces a canceling or diverting magnetic field which simulates the effect of movement of the closure member from the closed position thereof without any actual movement of the member.

Self-testing security sensor for monitoring closure of vault doors and the like

DOEpatents

Cawthorne, D.C.

1997-05-27

A self-testing device is provided for a monitoring system for monitoring whether a closure member such as a door or window is closed. The monitoring system includes a switch unit mounted on the frame of the closure member being monitored and including magnetically biased switches connected in one or more electrical monitoring circuits, and a door magnet unit mounted on the closure member being monitored. The door magnet includes one or more permanent magnets that produce a magnetic field which, when the closure member is closed, cause said switches to assume a first state. When the closure member is opened, the switches switch to a second, alarm state. The self-testing device is electrically controllable from a remote location and produces a canceling or diverting magnetic field which simulates the effect of movement of the closure member from the closed position thereof without any actual movement of the member. 5 figs.

Self-expanding platinum-coated nitinol devices for transcatheter closure of atrial septal defect: prevention of nickel release.

PubMed

Lertsapcharoen, Pornthep; Khongphatthanayothin, Apichai; Srimahachota, Suphot; Leelanukrom, Ruenreong

2008-06-01

A variety of nitinol-containing devices for transcatheter closure of atrial septal defects (ASD) has been widely used. However, there is concern about the release of nickel after nitinol device implantation. In this study, a platinum-coated nitinol device was braided from nanoplatinum-coated nitinol wires in order to prevent nickel release. The serum nickel levels before and after device implantation and the 1-year results were evaluated. Thirty-one patients, aged 4-59 years, and weighing 13.7-90.0 kg, underwent transcatheter closure. Blood samples for serum nickel levels were taken before, 1 day, 1 week, 1 month and 3 months after implantation. Twenty-nine (93.6%) patients had a successful implantation. The mean ASD diameter was 19.7 +/- 4.8 mm (range 10-30 mm). Procedure-related complications included transient brachial plexus injury in 1 patient and transient dysrhythmia in 4 patients. All 29 patients had complete closure within 1 month after implantation. The mean serum nickel levels at baseline and at 1 day, 1 week, 1 month and 3 months after implantation were 0.65 +/- 0.28, 0.63 +/- 0.18, 0.67 +/- 0.34, 0.55 +/- 0.16, 0.52 +/- 0.14 ng/ml, respectively. There was no significant difference in serum nickel levels before and after implantation. There were no device-related complications at 1-year follow up. Transcatheter ASD closure using a platinum-coated nitinol device can be performed safely and successfully with good outcomes. Nano-coating of platinum on nitinol wires can prevent nickel release following device implantation.

Mechanism of valvular regurgitation.

PubMed

Khoo, Nee S; Smallhorn, Jeffery F

2011-10-01

Despite improvements in surgical techniques, valvular regurgitation results in major morbidity in children with heart disease. Functional anatomy, mechanisms of valve closure and adaptation to changing hemodynamic stress in normal mitral and tricuspid valves are complex and only partially understood. As well, pathology of atrioventricular valve regurgitation is further complicated by congenital valve abnormalities involving leaflet tissue, supporting chordal apparatus and displaced papillary muscles. This review provides a current understanding of the mechanisms that result in atrioventricular valve failure. Mitral valve leaflets have contractile elements, in addition to atrial muscle modulation of leaflet tension. When placed under mechanical tethering stress, the mitral valve adapts by leaflet expansion, which increases coaptation surface reserve and chordal thickening. Both pediatric and adult studies are increasingly reporting on the importance of subvalvar apparatus function in maintaining valve competency. The maintenance of efficient valve function is accomplished by a complex series of events involving atrial and annular contraction, annular deformation, active leaflet tension, chordal transmission of papillary muscle contractions and ventricular contraction.

Device for installing rocket engines

NASA Technical Reports Server (NTRS)

George, T. R., Jr. (Inventor)

1976-01-01

A device for installing rocket engines is reported that is supported at a cant relative to vertical by an axially extensible, tiltable pedestal. A lifting platform supports the rocket engine at its thrust chamber exit, including a mount having a concentric base characterized by a concave bearing surface, a plurality of uniformly spaced legs extended radially from the base, and an annular receiver coaxially aligned with the base and affixed to the distal ends of said legs for receiving the thrust chamber exit. The lifting platform rests on a seat concentrically related to the pedestal and affixed to an extended end portion thereof having a convex bearing surface mated in sliding engagement with the concave bearing surface of the annular base for accommodating a rocking motion of the platform.

Tube coupling device

NASA Technical Reports Server (NTRS)

Myers, William N. (Inventor); Hein, Leopold A. (Inventor)

1987-01-01

A first annular ring of a tube coupling device has a keyed opening sized to fit around the nut region of a male coupling, and a second annular ring has a keyed opening sized to fit around the nut of a female coupling. Each ring has mating ratchet teeth and these rings are biased together, thereby engaging these teeth and preventing rotation of these rings. This in turn prevents the rotation of the male nut region with respect to the female nut. For tube-to-bulkhead locking, one facet of one ring is notched, and a pin is pressed into an opening in the bulkhead. This pin is sized to fit within one of the notches in the ring, thereby preventing rotation of this ring with respect to the bulkhead.

Short-Term Safety and Efficacy of Femoral Vascular Closure after Percutaneous Coronary Intervention with Combination of the Boomerang(TM) Device and Intravenous Protamine Sulfate.

PubMed

Chen, Ching-Pei; Huang, Huang-Kai; Hsia, Chien-Hsun; Chang, Yung-Ming; Lin, Lee-Shin; Lee, Cheng-Liang

2013-11-01

The Cardiva Boomerang(TM) is a device used to perform femoral vascular closure. It facilitates passive hemostasis at the arteriotomy site, leaving no residual foreign body. We performed a controlled, randomized study of 60 patients undergoing percutaneous coronary intervention. Patients were randomized into two groups (30 per group) to undergo vascular closure with the Boomerang(TM) or the Perclose(TM) suture-based device after the intravenous administration of protamine sulfate. We compared overall success rates, patient-reported pain, length of time to achieve hemostasis and mobilization of the patient, and the frequency of complications in the two groups. Overall success rates using the Boomerang(TM) and Perclose(TM) devices were similarly high, at 93% and 97%, respectively. The Boomerang(TM) was significantly quicker to deploy than the PercloseTM, device deployment time, median (Q1-Q3), [2.00 (1.33-2.75) vs. 3.84 (2.75-4.38) mins, p < 0.001)]. The pain score was significantly lower in the Boomerang(TM) group (1.1 ± 1.7 vs. 6.4 ± 2.9, p < 0.001). The time the device remained in the artery and manual compression time were significantly longer with the Boomerang(TM) (p < 0.001), as well as the time taken to achieve hemostasis and time to ambulation. There were no major complications in either group and no significant differences between the groups in the frequency of minor complications. We conclude that when used in combination with intravenous protamine sulfate, the Boomerang(TM) device is as safe and effective as the Perclose(TM) device for femoral vascular closure, but quicker to deploy and less painful to patients. Boomerang; Percutaneous intervention; Vascular closure device.

Endonasal Suturing of Nasoseptal Flap to Nasopharyngeal Fascia Using the V-Loc™ Wound Closure Device: 2-Dimensional Operative Video.

PubMed

Zwagerman, Nathan T; Geltzeiler, Mathew N; Wang, Eric W; Fernandez-Miranda, Juan C; Snyderman, Carl H; Gardner, Paul A

2018-05-30

We present a case of cerebrospinal fluid (CSF) leak after endoscopic endonasal resection of a large clival chordoma in an obese patient. The leak was at the lower reconstruction at the craniocervical junction and had failed repositioning. Using the V-Loc™ wound closure device (Covidien, New Haven, Connecticut) to suture the nasoseptal flap to the nasopharyngeal fascia, a water-tight seal was created and, along with a lumbar drain, the patient healed successfully.CSF leak after an endoscopic endonasal approach (EEA) to intradural pathologies remains one of the more common complications.1-4 Various closure techniques have been developed5-8 with success in mitigating this risk, but all have their limitations and rely on multiple layers including vascularized flaps like the nasoseptal flap.9-11 Endonasal suturing of graft materials offers the advantage of creating a water-tight seal. We present the use of the V-Loc™ wound closure device (Covidien) to successfully seal a postoperative CSF leak. The absorbable V-Loc™ wound closure device does not require the surgeon to tie knots, which is the most challenging step in a deep, 2-dimensional corridor. The suture is barbed and is anchored by threading the needle through a prefabricated loop at the end of the suture which locks in place. Each throw of the suture through tissue maintains the suture line as the barbs catch the tissue and prevent retraction. After successful closure, the needle can simply be cut off.The V-Loc™ wound closure device (Covidien) is a safe and effective adjunct to reconstruction after endoscopic endonasal skull base surgery as it provides an option for graft/flap suturing.A written release from the patient whose name or likeness is submitted as part of this Work is on file.

Patent ductus arteriosus closure using an Amplatzer™ ventricular septal defect closure device

PubMed Central

Fernando, Rajeev; Koranne, Ketan; Loyalka, Pranav; Kar, Biswajit; Gregoric, Igor

2013-01-01

The ductus arteriosus originates from the persistence of the distal portion of the left sixth aortic arch. It connects the descending aorta (immediately distal to the left subclavian artery) to the roof of the main pulmonary artery, near the origin of the left pulmonary artery. Persistence of the duct beyond 48 h after birth is abnormal and results in patent ductus arteriosus (PDA). PDA is rare in adults because it is usually discovered and treated in childhood. Mechanical closure remains the definitive therapy because the patency of ductus arteriosus may lead to multiple complications, depending on the size and flow through the ductus. PDA closure is indicated in patients with symptoms and evidence of left heart enlargement, and in patients with elevated pulmonary pressures when reversal is possible. Transcatheter closure is the preferred technique in adults because it avoids sternotomy, reduces the length of hospital stay and is associated with fewer complications compared with surgery. First demonstrated in 1967, both the technique and the occluder devices used have since evolved. However, designing an ideal PDA occluder has been a challenge due to the variability in size, shape and orientation of PDAs. The present article describes a case involving a 35-year-old woman who presented to the Center for Advanced Heart Failure (Houston, USA) with congestive heart failure due to a large PDA, which was successfully occluded using an Amplatzer (St Jude Medical, USA) muscular ventricular septal defect closure device. The wider waist and dual-retention discs of these ventricular septal defect closure devices may be important factors to consider in the future development of devices for the occlusion of large PDAs. PMID:24294051

Patent ductus arteriosus closure using an Amplatzer(™) ventricular septal defect closure device.

PubMed

Fernando, Rajeev; Koranne, Ketan; Loyalka, Pranav; Kar, Biswajit; Gregoric, Igor

2013-01-01

The ductus arteriosus originates from the persistence of the distal portion of the left sixth aortic arch. It connects the descending aorta (immediately distal to the left subclavian artery) to the roof of the main pulmonary artery, near the origin of the left pulmonary artery. Persistence of the duct beyond 48 h after birth is abnormal and results in patent ductus arteriosus (PDA). PDA is rare in adults because it is usually discovered and treated in childhood. Mechanical closure remains the definitive therapy because the patency of ductus arteriosus may lead to multiple complications, depending on the size and flow through the ductus. PDA closure is indicated in patients with symptoms and evidence of left heart enlargement, and in patients with elevated pulmonary pressures when reversal is possible. Transcatheter closure is the preferred technique in adults because it avoids sternotomy, reduces the length of hospital stay and is associated with fewer complications compared with surgery. First demonstrated in 1967, both the technique and the occluder devices used have since evolved. However, designing an ideal PDA occluder has been a challenge due to the variability in size, shape and orientation of PDAs. The present article describes a case involving a 35-year-old woman who presented to the Center for Advanced Heart Failure (Houston, USA) with congestive heart failure due to a large PDA, which was successfully occluded using an Amplatzer (St Jude Medical, USA) muscular ventricular septal defect closure device. The wider waist and dual-retention discs of these ventricular septal defect closure devices may be important factors to consider in the future development of devices for the occlusion of large PDAs.

Torus elements used in effective shock absorber

NASA Technical Reports Server (NTRS)

Cunningham, P.; Platus, D. L.

1966-01-01

Energy absorbing device forces torus elements to revolve annularly between two concentric tubes when a load is applied to one tube. Interference forces can be varied by using torus elements of different thicknesses. The device operates repeatedly in compression or tension, and under problems of large onset rate tolerance or structural overload.

ANNULAR IMPACTOR SAMPLING DEVICE

DOEpatents

Tait, G.W.C.

1959-03-31

A high-rate air sampler capable of sampling alphaemitting particles as small as 0.5 microns is described. The device is a cylindrical shaped cup that fits in front of a suction tube and which has sticky grease coating along its base. Suction forces contaminated air against the periodically monitored particle absorbing grease.

Prediction of left ventricular dysfunction after device closure of patent ductus arteriosus: proposal for a new functional classification.

PubMed

Kiran, Viralam S; Tiwari, Ashish

2018-04-06

The aims of this study were to determine the incidence and correlates of left ventricular (LV) dysfunction amongst percutaneous patent ductus arteriosus (PDA) device closure patients, and to propose an indexed parameter for predicting LV dysfunction. In a retrospective cross-sectional analysis of 30 months duration, 447 patients who underwent PDA device closure were studied. The diameter of the PDA at the pulmonary artery end was measured in the angiograms in all patients and was indexed for their body surface area. The indexed PDA size was categorised into group A (1-2.9 mm/m², 35/447), B (3-5.9 mm/m², 254/447), C (6-8.9 mm/m², 66/447) and D (>9 mm/m², 35/447). Systolic LV function was evaluated using echocardiography at frequent intervals. Overall, 62.63% of the patients were female (280/447). At baseline, all 447 patients had normal LV function. LV dysfunction was seen in 102/447 (22.8%) patients with 2.8% in category A (1/35), 10.6% in category B (27/254), 34.1% in category C (42/123) and 91.4% in category D (32/35) after PDA device closure. Correlation of indexed PDA size and LV dysfunction was statistically significant (p<0.05). Accurate prediction of LV dysfunction is important in risk stratification, ICU management and counselling in PDA device closures. Indexed PDA size correlates well with post-procedural LV dysfunction. The authors propose a new classification of PDA utilising this accurate, reproducible and easy to perform parameter, which does not involve any extra cost, for risk stratification and early management in device closure of PDA.

Study of the Synchronous Operation of an Annular Field Reversed Configuration Plasma Device

DTIC Science & Technology

2008-05-05

of pulsed diagnostics were developed to explore the operational characteristics of a 40 -cm outer diameter annular theta pinch and its pre-ionization...Optimized pre-ionization conditions, neutral gas densities, and plasma transition energies were determined for the 40 cm annulus in both argon and xenon...MSNW 100 25 10 10 150 Formation 1985 HBQM U Wash 300 22 5 5 30 Formation 1986 TRX-2 STI 100 24 13 10 100 Confinement 1987 CSS U Wash 100 45 3 40 60

Intrinsic rotation from a residual stress at the boundary of a cylindrical laboratory plasma.

PubMed

Yan, Z; Xu, M; Diamond, P H; Holland, C; Müller, S H; Tynan, G R; Yu, J H

2010-02-12

An azimuthally symmetric radially sheared azimuthal flow is driven by a nondiffusive, or residual, turbulent stress localized to a narrow annular region at the boundary of a cylindrical magnetized helicon plasma device. A no-slip condition, imposed by ion-neutral flow damping outside the annular region, combined with a diffusive stress arising from turbulent and collisional viscous damping in the central plasma region, leads to net plasma rotation in the absence of momentum input.

Transcatheter closure of the left atrial appendage: initial experience with the WATCHMAN device

PubMed Central

Ding, Jiandong; Zhu, Jian; Lu, Jing; Ding, Xiuxia; Zhang, Xiaoli; Lu, Wenbin; Ao, Mingqiang; Ma, Genshan

2015-01-01

Background: Atrial fibrillation (AF) is the most commonly encountered clinical arrhythmia, accounting for approximately one third of hospitalizations for cardiac rhythm disturbance. In patients with non-valvular AF, approximately 90% of thrombi are thought to arise from the left atrial appendage (LAA). Anticoagulation with warfarin has been the mainstay of therapy to reduce stroke risk in these patients; however, it is not without its complications including bleeding and drug interactions. Percutaneous left atrial appendage closure can be an alternative to warfarin treatment in patients with AF at high risk for thromboembolic events and/or bleeding complications. Methods: Patients with atrial fibrillation and CHADSVASc score ≥ 2, not eligible for anticoagulation, were submitted to left atrial appendage closure using the WATCHMAN device. The procedure was performed under general anaesthesia, and was guided by fluoroscopy and transoesophageal echocardiography. Results: Percutaneous LAA closure with the WATCHMAN device was performed in all patients. At 45-day follow-up no recurrent major adverse events and especially no thromboembolic events occurred. Conclusions: Transcatheter closure of the LAA with the WATCHMAN device is generally safe and feasible. Long-term follow-up will further reveal the risk and benefits of this therapy. PMID:26629008

Percutaneous closure of secundum type atrial septal defects: More than 5-year follow-up

PubMed Central

Snijder, Roel JR; Suttorp, Maarten J; Berg, Jurriën M Ten; Post, Martijn C

2015-01-01

AIM: To investigate long-term efficacy of two different devices more than five years after percutaneous atrial septal defect (ASD) closure in adults. METHODS: All patients who underwent percutaneous closure of an ASD in the St. Antonius Hospital, Nieuwegein, The Netherlands, between February 1998 and December 2006 were included. Percutaneous closure took place under general anaesthesia and transesophageal echocardiographic monitoring. Transthoracic echocardiography (TTE) was performed 24 h post-procedure to visualize the device position and to look for residual shunting using color Doppler. All complications were registered. All patients were invited for an outpatient visit and contrast TTE more than 5-years after closure. Efficacy was based on the presence of a residual right-to-left shunt (RLS), graded as minimal, moderate or severe. The presence of a residual left-to-right shunt (LRS) was diagnosed using color Doppler, and was not graded. Descriptive statistics were used for patients’ characteristics. Univariate analysis was used to identify predictors for residual shunting. RESULTS: In total, 104 patients (mean age 45.5 ± 17.1 years) underwent percutaneous ASD closure using an Amplatzer device (ASO) in 76 patients and a Cardioseal/Starflex device (CS/SF) in 28 patients. The mean follow-up was 6.4 ± 3.4 years. Device migration occurred in 4 patients of whom two cases occurred during the index hospitalization (1 ASO, 1 CS/SF). The other 2 cases of device migration occurred during the first 6 mo of follow-up (2 CS/SF). The recurrent thrombo-embolic event rate was similar in both groups: 0.4% per follow-up year. More than 12 mo post-ASD closure and latest follow-up, new-onset supraventricular tachyarrhythmia’s occurred in 3.9% and 0% for the ASO and CS/SF group, respectively. The RLS rate at latest follow-up was 17.4% (minimal 10.9%, moderate 2.2%, severe 4.3%) and 45.5% (minimal 27.3%, moderate 18.2%, severe 0%) for the ASO- and CS/SF groups, respectively. There was no residual LRS in both groups. CONCLUSION: Percutaneous ASD closure has good long-term safety and efficacy profiles. The residual RLS rate seems to be high more than 5 years after closure, especially in the CS/SF. Residual LRS was not observed. PMID:25810815

Percutaneous management of coronary sinus atrial septal defect: two cases representing the spectrum for device closure and a review of the literature.

PubMed

Sandeep, Nefthi; Slack, Michael C

2014-10-01

Coronary sinus atrial septal defects are the rarest defects of the atrial septum comprising <1% of the five different types of atrial septal defects. Despite the widespread adoption of percutaneous device closure of secundum atrial septal defects, the published experience with percutaneous device closure of coronary sinus atrial septal defects is limited to only a few isolated case reports because of uncertainty regarding safety and efficacy. Open-heart surgical repair remains the treatment of choice for coronary sinus atrial septal defects, although this may not be the only treatment option in selected cases. Herein we describe our own experience with two patients with different clinical presentations and our method of successful percutaneous coronary sinus atrial septal defect closure in each. We then present a review of the anatomic spectrum of coronary sinus atrial septal defects along with a review of contemporary surgical and percutaneous device treatment.

[Closure of wide patent ductus arteriosus using a fenestrated muscular VSD occluder device in a pediatric patient with Down syndrome and pulmonary hypertension].

PubMed

Güvenç, Osman; Saygı, Murat; Demir, İbrahim Halil; Ödemiş, Ender

2017-06-01

Patients with wide patent ductus arteriosus and significant pulmonary hypertension not treated in time constitute a significant problem for cardiologists. For these patients, tests that could aid in decision-making for further planning include reversibility and balloon occlusion tests performed in the catheterization laboratory. Devices developed for the closure of ductus as well as different devices with off-label use may be employed in patients scheduled for transcatheter occlusion. When result of reversibility test is borderline positive, the use of fenestrated device may be applicable for selected patients. Presently described is case of a 10-year-old patient with Down syndrome who had a wide ductus and systemic pulmonary hypertension. Transcatheter closure procedure was performed with off-label use of a fenestrated muscular ventricular septal defect occluder device.

Transseptal Guidewire Stabilization for Device Closure of a Large Pulmonary Arteriovenous Malformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joseph, George, E-mail: joseph59@gmail.com; Kunwar, Brajesh Kumar, E-mail: kunwar_brajesh@yahoo.com

A 46-year-old man presenting with massive hemoptysis was found to have a large pulmonary arteriovenous malformation (PAVM) in the right lung. Closure of the PAVM with an Amplatzer-type duct occluder was hampered by inability to advance the device delivery sheath into the PAVM due to vessel tortuosity and inadequate guidewire support. Atrial septal puncture was performed and a femorofemoral arteriovenous guidewire loop through the right pulmonary artery, PAVM, and left atrium was created. Traction on both ends of the guidewire loop allowed advancement of the device delivery sheath into the PAVM and successful completion of the procedure. Transseptal guidewire stabilizationmore » can be a valuable option during device closure of large PAVMs when advancement, stability, or kinking of the device delivery sheath is an issue.« less

Current topics in surgery for multiple ventricular septal defects.

PubMed

Yoshimura, Naoki; Fukahara, Kazuaki; Yamashita, Akio; Doki, Yoshinori; Takeuchi, Katsunori; Higuma, Tomonori; Senda, Kazutaka; Toge, Masayoshi; Matsuo, Tatsuro; Nagura, Saori; Aoki, Masaya; Sakata, Kimimasa; Sakai, Mari

2016-04-01

In this review article, we describe several topics, including the sandwich technique, the transatrial re-endocardialization technique, the limited apical left ventriculotomy approach and device closure. The sandwich technique was introduced for the closure of muscular ventricular septal defects (VSD) by sandwiching the septum between two felt patches placed in the left and right ventricle. This technique requires neither the transection of muscular trabeculae nor ventriculotomy. Although the sandwich technique has resulted in the improvement of surgical outcomes, cases of postoperative cardiac dysfunction have been reported. Multiple smaller VSDs have been closed with transatrial re-endocardialization. Septal dysfunction may be avoided through this technique, in which the septal trabeculae are approximated in two layers of superficial, endocardial running sutures. Recently, a number of reports have recommended a limited apical left ventriculotomy approach. With this technique, a much shorter incision of around 1 cm at the apex of the left ventricle may be sufficient for achieving the complete closure of apical muscular VSDs. The transcatheter or perventricular device closure of muscular VSDs has increasingly been performed with good results. Although favorable early and mid-term results of device closure have been reported, this method is not always safer or less invasive than surgical closure. Long-term evaluations should be performed to determine whether the right and left ventricular functions are affected by treatment with relatively large devices in the heart.

Left Atrial Appendage Eccentricity and Irregularity Are Associated With Residual Leaks After Percutaneous Closure.

PubMed

Rajwani, Adil; Shirazi, Masoumeh G; Disney, Patrick J S; Wong, Dennis T L; Teo, Karen S L; Delacroix, Sinny; Chokka, Ramesh G; Young, Glenn D; Worthley, Stephen G

2015-12-01

Predictors of residual leak following percutaneous LAA closure were evaluated. Left atrial appendage (LAA) closure aims to exclude this structure from the circulation, typically using a circular occluder. A noncircular orifice is frequently encountered however, and fibrous remodeling of the LAA in atrial fibrillation may restrict orifice deformation. Noncircularity may thus be implicated in the occurrence of residual leak despite an appropriately oversized device. Pre-procedural multislice computerized tomography was used to quantify LAA orifice eccentricity and irregularity. Univariate predictors of residual leak were identified with respect to the orifice, device, and relevant clinical variables, with the nature of any correlations then further evaluated. Eccentricity and irregularity indexes of the orifice in 31 individuals were correlated with residual leak even where the device was appropriately oversized. An eccentricity index of 0.15 predicted a residual leak with 85% sensitivity and 59% specificity. An irregularity index of 0.05 predicted a significant residual leak ≥3 mm with 100% sensitivity and 86% specificity. Orifice size, device size, degree of device oversize, left atrial volume, and pulmonary artery pressure were not predictors of residual leak. Eccentricity and irregularity of the LAA orifice are implicated in residual leak after percutaneous closure even where there is appropriate device over-size. Irregularity index in particular is a novel predictor of residual leak, supporting a closer consideration of orifice morphology before closure. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Apparatus and method for burning a lean, premixed fuel/air mixture with low NOx emission

DOEpatents

Kostiuk, Larry W.; Cheng, Robert K.

1996-01-01

An apparatus for enabling a burner to stably burn a lean fuel/air mixture. The burner directs the lean fuel/air mixture in a stream. The apparatus comprises an annular flame stabilizer; and a device for mounting the flame stabilizer in the fuel/air mixture stream. The burner may include a body having an internal bore, in which case, the annular flame stabilizer is shaped to conform to the cross-sectional shape of the bore, is spaced from the bore by a distance greater than about 0.5 mm, and the mounting device mounts the flame stabilizer in the bore. An apparatus for burning a gaseous fuel with low NOx emissions comprises a device for premixing air with the fuel to provide a lean fuel/air mixture; a nozzle having an internal bore through which the lean fuel/air mixture passes in a stream; and a flame stabilizer mounted in the stream of the lean fuel/air mixture. The flame stabilizer may be mounted in the internal bore, in which case, it is shaped and is spaced from the bore as just described. In a method of burning a lean fuel/air mixture, a lean fuel/air mixture is provided, and is directed in a stream; an annular eddy is created in the stream of the lean fuel/air mixture; and the lean fuel/air mixture is ignited at the eddy.

Use of percutaneous closure devices in the removal of central venous catheters from inadvertent arterial catheterizations.

PubMed

Guimaraes, M; Uflacker, R; Schonholz, C; Hannegan, C; Selby, B

2008-06-01

Although rare, misplacement of central venous catheters in supra-aortic arteries is potentially fatal. Five patients had safe catheters removal using percutaneous closure devices. Three patients were coagulopathic, 3 under intensive care and 1 in immediate postoperative limb amputation. Patients were treated successfully, with immediate hemostasis and without complications in a mean follow-up of 12.5 months. Although the number of patients is small, the closure devices proved to be safe. This is a minimally invasive alternative technique in the management of large bore catheters removed from non-compressible puncture sites such as subclavian and brachiocephalic arteries.

40 CFR 63.962 - Standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... shall control air emissions from the individual drain system using one or a combination of the following... closure device. (3) Junction box control requirements. Each junction box shall be equipped with controls as follows: (i) The junction box shall be equipped with a closure device (e.g., manhole cover, access...

40 CFR 63.962 - Standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... shall control air emissions from the individual drain system using one or a combination of the following... closure device. (3) Junction box control requirements. Each junction box shall be equipped with controls as follows: (i) The junction box shall be equipped with a closure device (e.g., manhole cover, access...

40 CFR 63.962 - Standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... shall control air emissions from the individual drain system using one or a combination of the following... closure device. (3) Junction box control requirements. Each junction box shall be equipped with controls as follows: (i) The junction box shall be equipped with a closure device (e.g., manhole cover, access...

40 CFR 63.962 - Standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... shall control air emissions from the individual drain system using one or a combination of the following... closure device. (3) Junction box control requirements. Each junction box shall be equipped with controls as follows: (i) The junction box shall be equipped with a closure device (e.g., manhole cover, access...

Validation of CTF Droplet Entrainment and Annular/Mist Closure Models using Riso Steam/Water Experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wysocki, Aaron J.; Salko, Robert K.

This report summarizes the work done to validate the droplet entrainment and de-entrainment models as well as two-phase closure models in the CTF code by comparison with experimental data obtained at Riso National Laboratory. The Riso data included a series of over 250 steam/water experiments that were performed in both tube and annulus geometries over a range of various pressures and outlet qualities. Experimental conditions were set so that the majority of cases were in the annular/mist ow regime. Measurements included liquid lm ow rate, droplet ow rate, lm thickness, and two-phase pressure drop. CTF was used to model 180more » of the tubular geometry cases, matching experimental geometry, outlet pressure, and outlet ow quality to experimental values. CTF results were compared to the experimental data at the outlet of the test section in terms of vapor and entrained liquid ow fractions, pressure drop per unit length, and liquid lm thickness. The entire process of generating CTF input decks, running cases, extracting data, and generating comparison plots was scripted using Python and Matplotlib for a completely automated validation process. All test cases and scripting tools have been committed to the COBRA-TF master repository and selected cases have been added to the continuous testing system to serve as regression tests. The dierences between the CTF- and experimentally-calculated ow fraction values were con- sistent with previous calculations by Wurtz, who applied the same entrainment correlation to the same data. It has been found that CTF's entrainment/de-entrainment predictive capability in the annular/mist ow regime for this particular facility is comparable to the licensed industry code, COBRAG. While lm and droplet predictions are generally good, it has been found that accuracy is diminished at lower ow qualities. This nding is consistent with the noted deciencies in the Wurtz entrainment model employed by CTF. The CTF predicted two-phase pressure drop in the annular/mist ow regime has been found to be highly inaccurate, exhibiting a clear bias with respect to the experimental data. This inaccuracy led to an investigation that revealed deciencies in the implementation of the annular/mist interfacial friction model, which should be investigated further in the future. Looking to published COBRAG results for this same facility reveal it exhibits no bias with regard to experimental pressure drop results. In addition to the problems with pressure drop prediction, the lm thickness was also signicantly under-predicted by CTF compared to both experimental data and Wurtz's analytical calculations. Film thickness is calculated using a simple geometric relationship and lm void fraction in CTF, which is dependent on slip ratio and interfacial friction. It is possible that the issues aecting the pressure drop and lm void prediction are related.« less

Transcatheter closure of large patent ductus arteriosus using custom made devices.

PubMed

Rohit, Manoj Kumar; Gupta, Ankur

2017-05-01

There has been a paradigm shift in the transcatheter closure of patent ductus arteriosus (PDA) over the last 45 years. With the availability of various coils, plugs and occluders, PDA of almost all shapes and sizes are amenable to transcatheter closure. However, very large PDA diagnosed late in life are being referred for surgical closure in the absence of availability of large size devices, especially in developing countries. In this case series, we have described four patients with large PDA, three of which were closed by transcatheter custom made PDA occluders. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

Preliminary experience with a new device for delayed sternal closure strategy in cardiac surgery.

PubMed

Santini, Francesco; Onorati, Francesco; Telesca, Mariassunta; Faggian, Giuseppe; Mazzucco, Alessandro

2012-06-01

Open chest management with delayed sternal closure (DSC) is a valuable strategy in the management of patients with postcardiotomy hemodynamic instability or severe coagulopathy. The conventional extemporized material available for off-label sternal stenting however may limit its efficacy. We evaluated outcomes of patients with refractory severe postcardiotomy cardiogenic shock (SPCCS) treated with DSC using a novel temporary sternal spreader (NTSS) which allows myocardial recovery by progressive controlled approximation of the sternal edges. Seven patients (4 male, mean age 66.5 ± 5 years) with refractory SPCCS showing acute hemodynamic instability at sternal closure, were implanted with the NTSS, consisting of stainless-steel branches linked to 2 diverging plates of polyether-ether ketone, whose progressive opening/closing mechanism can be controlled from outside the chest with a rotating steel wire. The sternal wound was closed by an elastic membrane to achieve a sterile field. Swan-Ganz monitoring was employed, and clinical outcomes evaluated. The device was successfully implanted in all patients without device-related complications or failures. Progressive approximation of sternal edges, titrated on cardiac index values, was successfully completed allowing subsequent uneventful sternal closure in all. Mean time from SPCCS to sternal closure was 70 ± 21 hours. No patient developed infective complications or late hemodynamic instability after device removal and sternal closure. One patient (14%) died of multiorgan failure on postoperative day 9. Despite the limited number of patients enrolled, the NTSS proved safe and effective in allowing complete myocardial recovery after SPCCS, avoiding hemodynamic instability related to abrupt sternal closure, with no occurrence of infective complications.

Multiphysics analysis of liquid metal annular linear induction pumps: A project overview

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maidana, Carlos Omar; Nieminen, Juha E.

Liquid metal-cooled fission reactors are both moderated and cooled by a liquid metal solution. These reactors are typically very compact and they can be used in regular electric power production, for naval and space propulsion systems or in fission surface power systems for planetary exploration. The coupling between the electromagnetics and thermo-fluid mechanical phenomena observed in liquid metal thermo-magnetic systems for nuclear and space applications gives rise to complex engineering magnetohydrodynamics and numerical problems. It is known that electromagnetic pumps have a number of advantages over rotating mechanisms: absence of moving parts, low noise and vibration level, simplicity of flowmore » rate regulation, easy maintenance and so on. However, while developing annular linear induction pumps, we are faced with a significant problem of magnetohydrodynamic instability arising in the device. The complex flow behavior in this type of devices includes a time-varying Lorentz force and pressure pulsation due to the time-varying electromagnetic fields and the induced convective currents that originates from the liquid metal flow, leading to instability problems along the device geometry. The determinations of the geometry and electrical configuration of liquid metal thermo-magnetic devices give rise to a complex inverse magnetohydrodynamic field problem were techniques for global optimization should be used, magnetohydrodynamics instabilities understood –or quantified- and multiphysics models developed and analyzed. Lastly, we present a project overview as well as a few computational models developed to study liquid metal annular linear induction pumps using first principles and the a few results of our multi-physics analysis.« less

Multiphysics analysis of liquid metal annular linear induction pumps: A project overview

DOE PAGES

Maidana, Carlos Omar; Nieminen, Juha E.

2016-03-14

Liquid metal-cooled fission reactors are both moderated and cooled by a liquid metal solution. These reactors are typically very compact and they can be used in regular electric power production, for naval and space propulsion systems or in fission surface power systems for planetary exploration. The coupling between the electromagnetics and thermo-fluid mechanical phenomena observed in liquid metal thermo-magnetic systems for nuclear and space applications gives rise to complex engineering magnetohydrodynamics and numerical problems. It is known that electromagnetic pumps have a number of advantages over rotating mechanisms: absence of moving parts, low noise and vibration level, simplicity of flowmore » rate regulation, easy maintenance and so on. However, while developing annular linear induction pumps, we are faced with a significant problem of magnetohydrodynamic instability arising in the device. The complex flow behavior in this type of devices includes a time-varying Lorentz force and pressure pulsation due to the time-varying electromagnetic fields and the induced convective currents that originates from the liquid metal flow, leading to instability problems along the device geometry. The determinations of the geometry and electrical configuration of liquid metal thermo-magnetic devices give rise to a complex inverse magnetohydrodynamic field problem were techniques for global optimization should be used, magnetohydrodynamics instabilities understood –or quantified- and multiphysics models developed and analyzed. Lastly, we present a project overview as well as a few computational models developed to study liquid metal annular linear induction pumps using first principles and the a few results of our multi-physics analysis.« less

Gas centrifuge purge method

DOEpatents

Theurich, Gordon R.

1976-01-01

1. In a method of separating isotopes in a high speed gas centrifuge wherein a vertically oriented cylindrical rotor bowl is adapted to rotate about its axis within an evacuated chamber, and wherein an annular molecular pump having an intake end and a discharge end encircles the uppermost portion of said rotor bowl, said molecular pump being attached along its periphery in a leak-tight manner to said evacuated chamber, and wherein end cap closure means are affixed to the upper end of said rotor bowl, and a process gas withdrawal and insertion system enters said bowl through said end cap closure means, said evacuated chamber, molecular pump and end cap defining an upper zone at the discharge end of said molecular pump, said evacuated chamber, molecular pump and rotor bowl defining a lower annular zone at the intake end of said molecular pump, a method for removing gases from said upper and lower zones during centrifuge operation with a minimum loss of process gas from said rotor bowl, comprising, in combination: continuously measuring the pressure in said upper zone, pumping gas from said lower zone from the time the pressure in said upper zone equals a first preselected value until the pressure in said upper zone is equal to a second preselected value, said first preselected value being greater than said second preselected value, and continuously pumping gas from said upper zone from the time the pressure in said upper zone equals a third preselected value until the pressure in said upper zone is equal to a fourth preselected value, said third preselected value being greater than said first, second and fourth preselected values.

Right ventricular pressure response to exercise in adults with isolated ventricular septal defect closed in early childhood.

PubMed

Moller, Thomas; Lindberg, Harald; Lund, May Brit; Holmstrom, Henrik; Dohlen, Gaute; Thaulow, Erik

2018-06-01

We previously demonstrated an abnormally high right ventricular systolic pressure response to exercise in 50% of adolescents operated on for isolated ventricular septal defect. The present study investigated the prevalence of abnormal right ventricular systolic pressure response in 20 adult (age 30-45 years) patients who underwent surgery for early ventricular septal defect closure and its association with impaired ventricular function, pulmonary function, or exercise capacity. The patients underwent cardiopulmonary tests, including exercise stress echocardiography. Five of 19 patients (26%) presented an abnormal right ventricular systolic pressure response to exercise ⩾ 52 mmHg. Right ventricular systolic function was mixed, with normal tricuspid annular plane systolic excursion and fractional area change, but abnormal tricuspid annular systolic motion velocity (median 6.7 cm/second) and isovolumetric acceleration (median 0.8 m/second2). Left ventricular systolic and diastolic function was normal at rest as measured by the peak systolic velocity of the lateral wall and isovolumic acceleration, early diastolic velocity, and ratio of early diastolic flow to tissue velocity, except for ejection fraction (median 53%). The myocardial performance index was abnormal for both the left and right ventricle. Peak oxygen uptake was normal (mean z score -0.4, 95% CI -2.8-0.3). There was no association between an abnormal right ventricular systolic pressure response during exercise and right or left ventricular function, pulmonary function, or exercise capacity. Abnormal right ventricular pressure response is not more frequent in adult patients compared with adolescents. This does not support the theory of progressive pulmonary vascular disease following closure of left-to-right shunts.

Theoretical and measured electric field distributions within an annular phased array: consideration of source antennas.

PubMed

Zhang, Y; Joines, W T; Jirtle, R L; Samulski, T V

1993-08-01

The magnitude of E-field patterns generated by an annular array prototype device has been calculated and measured. Two models were used to describe the radiating sources: a simple linear dipole and a stripline antenna model. The stripline model includes detailed geometry of the actual antennas used in the prototype and an estimate of the antenna current based on microstrip transmission line theory. This more detailed model yields better agreement with the measured field patterns, reducing the rms discrepancy by a factor of about 6 (from approximately 23 to 4%) in the central region of interest where the SEM is within 25% of the maximum. We conclude that accurate modeling of source current distributions is important for determining SEM distributions associated with such heating devices.

Transcatheter closure of ventricular septal defect with Occlutech Duct Occluder.

PubMed

Atik-Ugan, Sezen; Saltik, Irfan Levent

2018-04-01

Patent ductus arteriosus occluders are used for transcatheter closure of ventricular septal defects, as well as for closure of patent ductus arteriosus. The Occlutech Duct Occluder is a newly introduced device for transcatheter closure of patent ductus arteriosus. Here, we present a case in which the Occlutech Duct Occluder was successfully used on a patient for the closure of a perimembraneous ventricular septal defect.

Enhanced optical transmission through double-overlapped annular aperture array

NASA Astrophysics Data System (ADS)

Wang, Chaonan; Bai, Ming; Jin, Ming

2012-07-01

In this paper, transmission properties through an array of concentric or eccentric double-overlapped annular apertures (CDOAAs or EDOAAs) are investigated. It is demonstrated that local surface plasmon-assisted TE11-like modes in CDOAAs exhibit a blue shift with the increasing overlapped factor. For EDOAAs with asymmetric annular apertures in both directions, a new resonant peak can be excited at a larger wavelength using linearly polarised light, which corresponds to extreme field localisation around the narrowest gap attributed to the gap plasmons' excitation and is quite sensitive to the offset of the eccentric centre island. These properties provide a possible method to achieve multiplexed and tunable wavelength selection using different local surface plasmon resonances and are of significant potential applicable value to the designing of tunable optical devices.

40 CFR 63.906 - Inspection and monitoring requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... between the roof and the tank wall; broken, cracked, or otherwise damaged seals or gaskets on closure devices; and broken or missing hatches, access covers, caps, or other closure devices. (2) The owner or... air pollution control equipment designated as such a written explanation of the reasons why the...

40 CFR 63.1046 - Test methods and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... vapor leakage could occur) on the cover and associated closure devices shall be checked. Potential leak... test, the cover and closure devices shall be secured in the closed position. (3) The detection... constituent. (4) The detection instrument shall be calibrated before use on each day of its use by the...

40 CFR 63.964 - Inspection and monitoring requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... Defects include, but are not limited to, visible cracks, holes, or gaps in the closure devices; broken..., visible cracks, holes, or gaps in the closure devices; broken, cracked, or otherwise damaged seals or..., visible cracks, holes, gaps, or other open spaces in the sewer line joints, seals, or other emission...

40 CFR 63.964 - Inspection and monitoring requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... Defects include, but are not limited to, visible cracks, holes, or gaps in the closure devices; broken..., visible cracks, holes, or gaps in the closure devices; broken, cracked, or otherwise damaged seals or..., visible cracks, holes, gaps, or other open spaces in the sewer line joints, seals, or other emission...

Thermic sealing in femoral catheterisation: First experience with the Secure Device.

PubMed

Sacherer, Michael; Kolesnik, Ewald; von Lewinski, Friederike; Verheyen, Nicolas; Brandner, Karin; Wallner, Markus; Eaton, Deborah M; Luha, Olev; Zweiker, Robert; von Lewinski, Dirk

2018-04-03

Devices currently used to achieve hemostasis of the femoral artery following percutaneous cardiac catheterization are associated with vascular complications and remnants of artificial materials are retained at the puncture site. The SECURE arterial closure device induces hemostasis by utilizing thermal energy, which causes collagen shrinking and swelling. In comparison to established devices, it has the advantage of leaving no foreign material in the body following closing. This study was designed to evaluate the efficacy and safety of the SECURE device to close the puncture site following percutaneous cardiac catheterization. The SECURE device was evaluated in a prospective non-randomized single-centre trial with patients undergoing 6 F invasive cardiac procedures. A total of 67 patients were enrolled and the device was utilized in 63 patients. 50 diagnostic and 13 interventional cases were evaluated. Femoral artery puncture closure was performed immediately after completion of the procedure. Time to hemostasis (TTH), time to ambulation (TTA) and data regarding short-term and 30-day clinical follow-up were recorded. Mean TTH was 4:30 ± 2:15 min in the overall observational group. A subpopulation of patients receiving anticoagulants had a TTH of 4:53 ± 1:43 min. There were two access site complications (hematoma > 5 cm). No major adverse events were identified during hospitalization or at the 30 day follow-up. The new SECURE device demonstrates that it is feasible in diagnostic and interventional cardiac catheterization. With respect to safety, the SECURE device was non-inferior to other closure devices as tested in the ISAR closure trial.

Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture: Original Research Article: Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture

DOE PAGES

Pan, Wenxiao; Galvin, Janine; Huang, Wei Ling; ...

2018-03-25

In this paper we aim to develop a validated device-scale CFD model that can predict quantitatively both hydrodynamics and CO 2 capture efficiency for an amine-based solvent absorber column with random Pall ring packing. A Eulerian porous-media approach and a two-fluid model were employed, in which the momentum and mass transfer equations were closed by literature-based empirical closure models. We proposed a hierarchical approach for calibrating the parameters in the closure models to make them accurate for the packed column. Specifically, a parameter for momentum transfer in the closure was first calibrated based on data from a single experiment. Withmore » this calibrated parameter, a parameter in the closure for mass transfer was next calibrated under a single operating condition. Last, the closure of the wetting area was calibrated for each gas velocity at three different liquid flow rates. For each calibration, cross validations were pursued using the experimental data under operating conditions different from those used for calibrations. This hierarchical approach can be generally applied to develop validated device-scale CFD models for different absorption columns.« less

Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture: Original Research Article: Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Wenxiao; Galvin, Janine; Huang, Wei Ling

In this paper we aim to develop a validated device-scale CFD model that can predict quantitatively both hydrodynamics and CO 2 capture efficiency for an amine-based solvent absorber column with random Pall ring packing. A Eulerian porous-media approach and a two-fluid model were employed, in which the momentum and mass transfer equations were closed by literature-based empirical closure models. We proposed a hierarchical approach for calibrating the parameters in the closure models to make them accurate for the packed column. Specifically, a parameter for momentum transfer in the closure was first calibrated based on data from a single experiment. Withmore » this calibrated parameter, a parameter in the closure for mass transfer was next calibrated under a single operating condition. Last, the closure of the wetting area was calibrated for each gas velocity at three different liquid flow rates. For each calibration, cross validations were pursued using the experimental data under operating conditions different from those used for calibrations. This hierarchical approach can be generally applied to develop validated device-scale CFD models for different absorption columns.« less

Seven-year follow-up of percutaneous closure of patent foramen ovale.

PubMed

Mirzada, Naqibullah; Ladenvall, Per; Hansson, Per-Olof; Johansson, Magnus Carl; Furenäs, Eva; Eriksson, Peter; Dellborg, Mikael

2013-12-01

Observational studies favor percutaneous closure of patent foramen ovale (PFO) over medical treatment to reduce recurrent stroke while randomized trials fail to demonstrate significant superiority of percutaneous PFO closure. Few long-term studies are available post PFO closure. This study reports long-term clinical outcomes after percutaneous PFO closure. Between 1997 and 2006, 86 consecutive eligible patients with cerebrovascular events, presumably related to PFO, underwent percutaneous PFO closure. All 86 patients were invited to a long-term follow-up, which was carried out during 2011 and 2012. Percutaneous PFO closure was successfully performed in 85 of 86 patients. The follow-up rate was 100%. No cardiovascular or cerebrovascular deaths occurred. Two patients (both women) died from lung cancer during follow-up. Follow-up visits were conducted for 64 patients and the remaining 20 patients were followed up by phone. The mean follow-up time was 7.3 years (5 to 12.4 years). Mean age at PFO closure was 49 years. One patient had a minor stroke one month after PFO closure and a transient ischemic attack (TIA) two years afterwards. One other patient suffered from a TIA six years after closure. No long-term device-related complications were observed. Percutaneous PFO closure was associated with very low risk of recurrent stroke and is suitable in most patients. We observed no mortality and no long-term device-related complications related to PFO closure, indicating that percutaneous PFO closure is a safe and efficient treatment even in the long term.

Study design of the CLOSURE I Trial: a prospective, multicenter, randomized, controlled trial to evaluate the safety and efficacy of the STARFlex septal closure system versus best medical therapy in patients with stroke or transient ischemic attack due to presumed paradoxical embolism through a patent foramen ovale.

PubMed

Furlan, Anthony J; Reisman, Mark; Massaro, Joseph; Mauri, Laura; Adams, Harold; Albers, Gregory W; Felberg, Robert; Herrmann, Howard; Kar, Saibal; Landzberg, Michael; Raizner, Albert; Wechsler, Lawrence

2010-12-01

Some strokes of unknown etiology may be the result of a paradoxical embolism traversing through a nonfused foramen ovale (patent foramen ovale [PFO]). The utility of percutaneously placed devices for treatment of patients with cryptogenic stroke or transient ischemic attack (TIA) and PFO is unknown. In addition, there are no clear data about the utility of medical interventions or other surgical procedures in this situation. Despite limited data, many patients are being treated with PFO closure devices. Thus, there is a strong need for clinical trials that test the potential efficacy of PFO occlusive devices in this situation. To address this gap in medical knowledge, we designed the CLOSURE I trial, a randomized, clinical trial comparing the use of a percutaneously placed PFO occlusive device and best medical therapy versus best medical therapy alone for prevention of recurrent ischemic neurologic symptoms among persons with TIA or ischemic stroke. This prospective, multicenter, randomized, controlled trial has finished enrollment. Two-year follow-up for all 910 patients is required. The primary end point is the 2-year incidence of stroke or TIA, all-cause mortality for the first 30 days, and neurologic mortality from ≥ 31 days of follow-up, as adjudicated by a panel of physicians who are unaware of treatment allocation. This article describes the rationale and study design of CLOSURE I. This trial should provide information as to whether the STARFlex septal closure system is safe and more effective than best medical therapy alone in preventing recurrent stroke/TIA and mortality in patients with PFO and whether the STARFlex septal closure device can demonstrate superiority compared with best medical therapy alone. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00201461.

The convertible flywheel

NASA Astrophysics Data System (ADS)

Ginsburg, B. R.

The design and testing of a new twin-disk composite flywheel is described. It is the first flywheel to store 2 kW-hr of energy and the first to successfully combine the advantages of composite materials with metal hubs, thus providing a system-ready flywheel with high energy storage and high torque capabilities. The use of flywheels in space for energy storage in satellites and space stations is examined. The convertibility of the present flywheel to provide the next generation Annular Momentum Control Device or Annular Suspension and Pointing System is discussed.

75 FR 69089 - Guidance for Industry and Food and Drug Administration Staff; Class II Special Controls Guidance...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-10

...: Tissue Adhesive With Adjunct Wound Closure Device Intended for the Topical Approximation of Skin... Document: Tissue Adhesive with Adjunct Wound Closure Device Intended for the Topical Approximation of Skin... intended for the topical approximation of skin may comply with the requirement of special controls for...

Transcatheter patent foramen ovale closure versus medical therapy for cryptogenic stroke: a meta-analysis of randomized clinical trials.

PubMed

Riaz, Irbaz Bin; Dhoble, Abhijeet; Mizyed, Ahmad; Hsu, Chiu-Hsieh; Husnain, Muhammad; Lee, Justin Z; Lotun, Kapildeo; Lee, Kwan S

2013-12-11

There is an association between cryptogenic stroke and patent foramen ovale (PFO). The optimal treatment strategy for secondary prevention remains unclear. The purpose of this study was to analyze aggregate data examining the safety and efficacy of transcatheter device closure versus standard medical therapy in patients with PFO and cryptogenic stroke. A search of published data identified 3 randomized clinical trials for inclusion. The primary outcome was a composite end-point of death, stroke and transient-ischemic attack (TIA). Pre-defined subgroup analysis was performed with respect to baseline characteristics including age, sex, atrial septal aneurysm and shunt size. Data was synthesized using a random effects model and results presented as hazard ratios (HRs) with 95% confidence intervals (CIs). A cohort of 2,303 patients with a history of cryptogenic stroke and PFO were randomized to device closure (n = 1150) and medical therapy (n = 1153). Mean follow-up was 2.5 years. Transcatheter closure was not superior to medical therapy in the secondary prevention of stroke or TIA in intention-to-treat analysis (HR: 0.66, 95% CI: 0.43 to 1.01; p = 0.056). However, the results were statistically significant using per-protocol analysis (HR: 0.64, 95% CI: 0.41 to 0.98; p = 0.043). Males had significant benefit with device closure (HR: 0.48, 95% CI: 0.24 to 0.96; p = 0.038). In this meta-analysis, using intention-to-treat analysis, transcatheter device closure of PFO was not superior to standard medical therapy in the secondary prevention of cryptogenic stroke. Transcatheter closure was superior using per-protocol analysis.

Leaflet Area as a Determinant of Tricuspid Regurgitation Severity in Patients with Pulmonary Hypertension

PubMed Central

Afilalo, Jonathan; Grapsa, Julia; Nihoyannopoulos, Petros; Beaudoin, Jonathan; Gibbs, J. Simon R.; Channick, Richard N.; Langleben, David; Rudski, Lawrence G.; Hua, Lanqi; Handschumacher, Mark D.; Picard, Michael H.; Levine, Robert A.

2015-01-01

Background Tricuspid regurgitation (TR) is a risk factor for mortality in pulmonary hypertension (PH). TR severity varies among patients with comparable degrees of PH and right ventricular (RV) remodeling. The contribution of leaflet adaptation to the pathophysiology of TR has yet to be examined. We hypothesized that tricuspid leaflet area (TLA) is increased in PH, and that its size relative to RV remodeling determines TR severity. Methods and Results A prospective cohort of 255 patients with PH from pre- and post-capillary etiologies was assembled from two centers. Patients underwent a 3-D echocardiogram focused on the tricuspid apparatus. TLA was measured with the Omni custom software package. Compared with normal controls, PH patients had a twofold increase in RV volumes, 62% increase in annulus area, and 49% increase in TLA. Those with severe TR demonstrated inadequate increase in TLA relative to the closure area, such that the ratio of TLA-to-closure area <1.78 was highly predictive of severe TR (odds ratio 68.7; 95% CI 16.2, 292.7). The median vena contracta width was 8.5 mm in the group with small TLA and large closure area as opposed to 4.8 mm in the group with large TLA and large closure area. Conclusions TLA plays a significant role in determining which patients with PH develop severe functional TR. The ratio of TLA-to-closure area, reflecting the balance between leaflet adaptation vs. annular dilation and tethering forces, is an indicator of TR severity that may identify which patients stand to benefit from leaflet augmentation during tricuspid valve repair. PMID:25977303

Percutaneous closure of patent arterial ducts in patients from high altitude: a sub-Saharan experience.

PubMed

Tefera, Endale; Qureshi, Shakeel A; Bermudez-Cañete, Ramòn; Rubio, Lola

2015-01-01

At high altitude, patent arterial ducts tend to be larger and associated with pulmonary hypertension. Patent ductus arteriosus device closure in this background could be challenging. We report our experience with percutaneous closure of patent arterial ducts using a variety of devices in patients residing in a high altitude. This is a retrospective review of the case records of 145 patients (age 9 months-20 years, mean 5.6 ± 3.9 years, and weight 7-54 kg, mean 17.7 ± 9.4) with duct sizes ranging between 2 and 21 mm, (mean, 5.8 ± 2.7) who underwent percutaneous closure of patent arterial ducts. One hundred thirty-six (93.8%) of the patients were from a geographic area of 2100-2800 m above sea level. Successful device closure was achieved in 143 cases. It was difficult to achieve device stability in two patients with expansile ducts. Therefore, they were treated surgically. The devices used were various types of duct occluder devices in 131 patients, while atrial and ventricular septal occluders were used in eight patients. For the group, mean systolic pulmonary artery (PA) pressure decreased from 47.0 ± 16.7 mmHg before occlusion to 29.0 ± 7.4 mmHg after occlusion (P ≤ 0.001)., mean diastolic PA pressure from 25.0 ± 10.9 mmHg to 14.8 ± 6.0 mmHg and the average mean PA pressure decreased from 35.9 ± 13.5 mmHg to 21.1 ± 6.5 mmHg. Complications (4.8%) included device and coil embolization, bleeding, and pulse loss. On follow-up (mean duration of 36.1 ± 12.1 months, range 12-62 months), 137 patients were in functional class 1, 3 had residual shunt, 2 had device migration and one patient had persisting pulse loss. Successful duct closure was achieved in the vast majority of patients, even though the ducts were larger and significant number of them had pulmonary hypertension in this high altitude group. There was a relatively higher incidence of residual shunts and device migration in this series, generally due to the nonavailability of optimal device and surgical support. Long-term follow-up is required before we can draw conclusions with regard to the sustainability of drop in PA pressures. Septal Occluder devices may be a possible alternative for large tubular or window-type ducts with severe pulmonary hypertension, where there may be concerns about the size and stability of duct occluder devices.

Nickel elution properties of contemporary interatrial shunt closure devices.

PubMed

Verma, Divya Ratan; Khan, Muhammad F; Tandar, Anwar; Rajasekaran, Namakkal S; Neuharth, Renée; Patel, Amit N; Muhlestein, Joseph B; Badger, Rodney S

2015-02-01

We sought to compare nickel elution properties of contemporary interatrial shunt closure devices in vitro. There are two United States Food and Drug Administration (FDA)-approved devices for percutaneous closure of secundum atrial septal defect: the Amplatzer septal occluder (ASO; St Jude Medical Corporation) and Gore Helex septal occluder (HSO; W.L. Gore & Associates). The new Gore septal occluder (GSO) device is in clinical trials. These are also used off-label for patent foramen ovale closure in highly selected patients. These devices have high nickel content. Nickel allergy is the most common reason for surgical device explantation. Nickel elution properties of contemporary devices remain unknown. We compared nickel elution properties of 4 devices - ASO, GSO, HSO, and sternal wire (SW) - while Dulbecco's phosphate-buffered saline (DPBS) served as control. Three samples of each device were submerged in DPBS. Nickel content was measured at 14 intervals over 90 days. Nickel elution at 24 hours, compared to control (0.005 ± 0.0 mg/L), was significantly higher for ASO (2.98 ± 1.65 mg/L; P=.04) and SW (0.03 ± 0.014 mg/L; P=.03). Nickel levels at 90 days, compared to control (0.005 ± 0.0 mg/L) and adjusting for multiple comparisons, were significantly higher for ASO (19.80 ± 2.30 mg/L; P=.01) and similar for HSO (P=.34), GSO (P=.34), and SW (P=.34). ASO had significantly higher nickel elution compared to HSO, GSO, and SW (P=.01). There is substantial variability in nickel elution; devices with less exposed nickel (HSO and GSO) have minimal elution. The safety of low nickel elution devices in patients with nickel allergy needs to be evaluated in prospective trials.

Novel percutaneous suture-mediated patent foramen ovale closure technique. Early results of the NobleStitch EL Italian Registry.

PubMed

Gaspardone, Achille; De Marco, Federico; Sgueglia, Gregory A; De Santis, Antonella; Iamele, Maria; D'Ascoli, Emanuela; Tusa, Maurizio; Corciu, Anca; Mullen, Michael; Nobles, Anthony; Carminati, Mario; Bedogni, Francesco

2018-04-03

To assess the efficacy of a novel percutaneous "device-less" suture mediated patent foramen ovale (PFO) closure system. Between June 2016 and October 2017, a prospective registry aimed at assessing the safety and efficacy of the NobleStitch EL (HeartStitch, Fountain Valley, CA) suture-based PFO closure system was carried out at 12 sites in Italy. Among 200 consecutive evaluated patients, 192 were considered suitable for suture-mediated PFO closure (44±13 years, 114 women). Suture of the septum with the NobleStitch EL system was carried out successfully in 186 (96%) patients. Median fluoroscopy time was 16.1 (13.0-22.5) minutes and contrast volume 200 (150-270) ml. At 206±130 days follow-up, microbubbles transthoracic echocardiography with Valsalva maneuver revealed no RLS (grade 0) in 139 (75%) patients and RLS grade ≤1 in 166 (89%) patients. Significant RLS was present in 20 (11%) patients (grade 2 and 3 in 11 and 9 patients, respectively). There were no device-related complications. The early results of this first Italian Registry indicates that the suture mediated "deviceless" closure of PFO is feasible in the majority of septal anatomies, provides an effective closure of PFO comparable to traditional devices with an excellent safety profile at medium term follow-up.

Device for separating CO2 from fossil-fueled power plant emissions

DOEpatents

Burchell, Timothy D [Oak Ridge, TN; Judkins, Roddie R [Knoxville, TN; Wilson, Kirk A [Knoxville, TN

2002-04-23

A gas separation device includes an inner conduit, and a concentric outer conduit. An electrically conductive filter media, preferably a carbon fiber composite molecular sieve, is provided in the annular space between the inner conduit and the outer conduit. Gas flows through the inner conduit and the annular space between the inner conduit and the outer conduit, so as to contact the filter media. The filter media preferentially adsorbs at least one constituent of the gas stream. The filter media is regenerated by causing an electric current to flow through the filter media. The inner conduit and outer conduit are preferably electrically conductive whereby the regeneration of the filter media can be electrically stimulated. The invention is particularly useful for the removal of CO.sub.2 from the exhaust gases of fossil-fueled power plants.

The CDRH helix. A phase I clinical trial.

PubMed

Shimm, D S; Cetas, T C; Hynynen, K H; Buechler, D N; Anhalt, D P; Sykes, H F; Cassady, J R

1989-04-01

Seventeen patients have been given regional hyperthermia treatments using the Center for Devices and Radiologic Health (CDRH) Helix, a resonant helical coil unit. Most of these patients had large, clinically advanced tumors, whose mean volume exceeded 1000 cc. Mean maximum, minimum, and average temperatures were 40.6, 38.6, and 39.6 degrees C, respectively, for all sites combined. The pelvic heating capabilities of the CDRH Helix and the BSD-1000 annular phased array were compared, and generally were equivalent. Although the Helix could be used in a wider variety of locations, and was more comfortable and easier to use than the BSD-1000 annular phased array, neither device was particularly effective in generating clinically useful temperatures; the Helix is currently under investigation for use in regional-systemic hyperthermia in combination with antineoplastic drugs and biologic response modifiers.

Hydrodynamic characteristics of a novel annular spouted bed with multiple air nozzles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gong, X.W.; Hu, G.X.; Li, Y.H.

A novel spouted bed, namely, an annular spouted bed with multiple air nozzles, has been proposed for drying, pyrolysis, and gasification of coal particulates. It consists of two homocentric upright cylinders with some annularly located spouting air nozzles between inner and outer cylinders. Experiments have been performed to study hydrodynamic characteristics of this device. The test materials studied are ash particle, soy bean, and black bean. Three distinct spouting stages have been examined and outlined with the hold-ups increase. In the fully developed spouting stage, three flow behaviors of particles have been observed and delimited. The effects of nozzle modemore » and spouting velocity on the maximum spouting height of the dense-phase region, spoutable static bed height, and spouting pressure drop in the bed have been investigated experimentally.« less

Percutaneous closure of a large patent ductus arteriosus in a preterm newborn weighing 1400 g without using arterial sheath: an innovative technique.

PubMed

Garg, Gaurav; Garg, Vishal; Prakash, Amit

2018-03-01

Percutaneous closure of patent ductus arteriosus is well established in infants weighing >5 kg, but data regarding outcome of preterm especially very low birth weight infants is minimal. Although surgical ligation of patent ductus arteriosus is the preferred and well-accepted modality of treatment after failure of drug therapy in preterm infants, it has also got its own demerits in such a small and fragile subset. Device closure in infants weighing <1.5 kg is rarely attempted because of high chances of complications, especially acute arterial injury due to the arterial sheath. We received a 1.4-kg ventilator-dependent infant for closure of large patent ductus arteriosus. Percutaneous closure of patent ductus arteriosus was done successfully and the infant was discharged on room air with a weight of 1.8 kg. We present here an innovative technique in which successful patent ductus arteriosus device closure was done in a 1.4-kg infant without using arterial sheath.

Computer fluid dynamics (CFD) study of a micro annular gear pump

NASA Astrophysics Data System (ADS)

Stan, Liviu-Constantin; Cǎlimǎnescu, Ioan

2016-12-01

Micro technology makes it possible to design products simply, efficiently and sustainably and at the same time, opens up the creation of new functionalities. The field of application of the micro annular gear pumps lies in analytical instrumentation, mechanical and plant engineering, chemical and pharmaceutical process engineering as well as in new markets like fuel cells or biotechnology, organic electronics or aerospace. The purpose of this paper is to investigate by using the powerful ANSYS 16 CFX module the hydrodynamic behavior of an 8/9 teeth annular gear pump. The solving of solids evolving inside fluids was very cumbersome until the advent of the Ansys immersed solid technology. By deploying this technology for very special topics like the CFD analysis of Micro annular gear pumps, credible and reliable results may be pulled leading thus the way for more in depth studies like geometrical a functional optimization of the existing devices. This paper is a valuable guide for the professionals working in the design field of micro pumps handing them a new and powerful design tool.

Modeling Subgrid Scale Droplet Deposition in Multiphase-CFD

NASA Astrophysics Data System (ADS)

Agostinelli, Giulia; Baglietto, Emilio

2017-11-01

The development of first-principle-based constitutive equations for the Eulerian-Eulerian CFD modeling of annular flow is a major priority to extend the applicability of multiphase CFD (M-CFD) across all two-phase flow regimes. Two key mechanisms need to be incorporated in the M-CFD framework, the entrainment of droplets from the liquid film, and their deposition. Here we focus first on the aspect of deposition leveraging a separate effects approach. Current two-field methods in M-CFD do not include appropriate local closures to describe the deposition of droplets in annular flow conditions. As many integral correlations for deposition have been proposed for lumped parameters methods applications, few attempts exist in literature to extend their applicability to CFD simulations. The integral nature of the approach limits its applicability to fully developed flow conditions, without geometrical or flow variations, therefore negating the scope of CFD application. A new approach is proposed here that leverages local quantities to predict the subgrid-scale deposition rate. The methodology is first tested into a three-field approach CFD model.

Device and method for imploding a microsphere with a fast liner

DOEpatents

Thode, Lester E.

1981-01-01

A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner to drive the fast liner to implode a microsphere.

Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

DOEpatents

Thode, Lester E.

1981-01-01

A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

Transcatheter Closure of Patent Ductus Arteriosus in Children with the Occlutech Duct Occluder.

PubMed

Bilici, Meki; Demir, Fikri; Akın, Alper; Türe, Mehmet; Balık, Hasan; Kuyumcu, Mahir

2017-12-01

The aim of this study was to evaluate the feasibility, efficacy and safety of transcatheter closure of patent ductus arteriosus (PDA) with the Occlutech duct occluder (ODO) in children. We reviewed the clinical records of 71 patients who underwent percutaneous closure of PDA with an ODO between September 2014 and August 2016. The Occlutech duct occluder was applied to 71 patients during the study period (September 2014-August 2016), and the results were analyzed in this study. Forty-two of the patients were female and 29 male. The median age was 20.5 months (range, 6-194 months) and median weight was 16 kg (range, 6-68 kg). The PDA was classified as type A in 54 patients (76.1%), type E in 14 (19.7%), type C in 2 (2.8%) and type B in 1 (1.4%) based on the Krichenko classification. A standard ODO device was used for the transcatheter closure procedure in 66 patients and the long-shank ODO device in 5. In the echocardiographic measurement of PDA, the median smallest diameter was 2.7 mm (range, 1.5-7.0 mm), and in the angiographic measurement, the median smallest diameter was 2.5 mm (range, 1.5-6.5 mm). All 71 patients underwent successful PDA closure with the ODO. Angiography following the procedure showed complete closure in 47 patients (66.2%), mild residual shunt in 13 patients (18.3%) and a trivial shunt in 11 patients (15.5%). Color flow Doppler echocardiogpaphy at 24 h post-implantation showed that complete closure was achieved in 65 patients (91.5%), and 6 patients (8.5%) had mild residual shunt. All patients (100%) had complete closure at 30 days of follow-up. The results of this study showed that the Occlutech PDA occluder device is safe and effective in the closure of PDA. As the pulmonary artery side of the device is wider than the aortic side, protrusion toward the aortic side and embolization are prevented, but there is residual shunt in the early period, although this residual shunt disappeared after a few months.

Feasibility and safety of a new generation of gore septal occluder device in children.

PubMed

Lombardi, Maristella; Tagliente, Maria R; Pirolo, Teodoro; Massari, Elena; Milella, Leonardo; Vairo, Ugo

2016-12-01

Transcatheter closure of an ostium secundum atrial septal defect (ASD) is now considered the standard care for most of children with the appropriate anatomy, and is a relatively well-tolerated procedure to reduce the clinical sequelae of ASD, with a low complication rate. The present case reports describe our clinical experience of the percutaneous closure of a secundum ASD in 10 children between December 2011 and November 2012, by means of a new generation of device, the GORE Septal Occluder device. The implantation was successful in all except two cases, the device being properly placed and deployed without malposition or embolization in the catheterization laboratory. No complications were related to the procedure. The successful implant was confirmed and no major adverse events were documented in the following 3-12 months. The new GORE Septal Occluder device appears to be a feasible, well-tolerated and successful tool for the closure of an ASD of 15 mm or less in childhood.

Cost-effectiveness analysis of different devices used for the closure of small-to-medium-sized patent ductus arteriosus in pediatric patients

PubMed Central

El-Saiedi, Sonia A; El Sisi, Amal M; Mandour, Rodina Sobhy; Abdel-Aziz, Doaa M; Attia, Wael A

2017-01-01

Aims: In this study, we examined the differences in cost and effectiveness of various devices used for the closure of small to medium sized patent ductus arteriosus (PDA). Setting and Design: We retrospectively studied 116 patients who underwent closure of small PDAs between January 2010 and January 2015. Subjects and Methods: Three types of devices were used: the Amplatzer duct occluder (ADO) II, the cook detachable coil and the Nit Occlud coil (NOC). Immediate and late complications were recorded and patients were followed up for 3 months after the procedure. Statistical Methods: All statistical calculations were performed using Statistical Package for the Social Science software. P <0.05 were considered significant. Results: We successfully deployed ADO II devices in 33 out of 35 cases, cook detachable coils in 36 out of 40 cases and NOCs in 38 out of 41 cases. In the remaining nine cases, the first device was unsuitable or embolized and required retrieval and replacement with another device. Eleven patients (9.5%) developed vascular complications and required anticoagulation therapy. Patients who had hemolysis or vascular complications remained longer in the intensive care unit, with consequently higher total cost (P = 0.016). Also, the need for a second device increased the cost per patient. Conclusions: The cook detachable coil is the most cost-effective device for closure of small-to medium-sized PDAs. Calculations of the incremental cost-effectiveness. (ICE) revealed that the Cook detachable coil had less ICE than the ADO II and NOC. The NOC was more effective with fewer complications. PMID:28566822

Effects of transcatheter closure of Fontan fenestration on exercise tolerance. kidecho@yahoo.com.

PubMed

Momenah, Tarek S; Eltayb, Haifa; Oakley, Reida El; Qethamy, Howeida Al; Faraidi, Yahya Al

2008-05-01

Baffle fenestration is associated with a significantly better outcome in standard and high-risk patients undergoing completion of Fontan. We report the effects of subsequent transcatheter closure of fenestration on exercise capacity and oxygen saturation. Sixteen patients with a mean age of 10.3 years underwent Amplatzer septal occluder (ASO) device transcatheter closure of Fontan fenestration. All had a fenestrated Fontan operation 6 month to 8 years prior to the procedure. A stress test was performed before and after device closure of fenestration in 14 patients (2 patients did not tolerate stress test before the procedure). The fenestrations in all patients were successfully occluded with the use of the Amplatzer device occluder. No complications occurred during or after the procedure. O2 saturation increased from a mean 85.1 +/- 7.89% to 94.5 +/- 3.63% (p < 0.01) at rest and from 66.2 +/- 12.86% to 87.2 +/- 8.64% (p < 0.01) following exercise. Exercise duration has also increased from 8.22 +/- 2.74 min to 10.29 +/- 1.91 min (p < 0.05). Transcatheter closure of Fontan fenestration increases the duration of exercise capacity and increases O2 saturation at rest and after exercise.

Annular phased-array high-intensity focused ultrasound device for image-guided therapy of uterine fibroids.

PubMed

Held, Robert Thomas; Zderic, Vesna; Nguyen, Thuc Nghi; Vaezy, Shahram

2006-02-01

An ultrasound (US), image-guided high-intensity focused ultrasound (HIFU) device was developed for noninvasive ablation of uterine fibroids. The HIFU device was an annular phased array, with a focal depth range of 30-60 mm, a natural focus of 50 mm, and a resonant frequency of 3 MHz. The in-house control software was developed to operate the HIFU electronics drive system for inducing tissue coagulation at different distances from the array. A novel imaging algorithm was developed to minimize the HIFU-induced noise in the US images. The device was able to produce lesions in bovine serum albumin-embedded polyacrylamide gels and excised pig liver. The lesions could be seen on the US images as hyperechoic regions. Depths ranging from 30 to 60 mm were sonicated at acoustic intensities of 4100 and 6100 W/cm2 for 15 s each, with the latter producing average lesion volumes at least 63% larger than the former. Tissue sonication patterns that began distal to the transducer produced longer lesions than those that began proximally. The variation in lesion dimensions indicates the possible development of HIFU protocols that increase HIFU throughput and shorten tumor treatment times.

Successful Retrieval of an Embolized Vascular Closure Device (Angio-Seal{sup ®}) After Peripheral Angioplasty

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jud, Philipp, E-mail: philipp.jud@medunigraz.at; Portugaller, Rupert; Bohlsen, Dennis

A 55-year-old male with peripheral arterial disease underwent angioplasty of the right lower limb arteries via antegrade femoral access. Angio-Seal{sup ®} closure device was used to treat the puncture site, whereby the intravascular sealing anchor accidentally embolized into the malleolar region of the right posterior tibial artery. Successful retrieval of the anchor was accomplished by a SpiderFX embolic protection device. This technique may be a useful approach to retrieve embolized foreign bodies via endovascular access.

Device-less patent foramen ovale closure by radiofrequency thermal energy.

PubMed

Walpoth, Nazan B; Habermacher, Kathrin; Moarof, Igal; Watson, Sandy; Wahl, Andreas; Windecker, Stephan; Schönenberger, Christa; Meier, Bernhard

2008-02-23

The goal of this study was to assess the feasibility, safety and success of a system which uses radiofrequency energy (RFE) rather than a device for percutaneous closure of patent foramen ovale (PFO). Sixteen patients (10 men, 6 women, mean age 50 years) were included in the study. All of them had a proven PFO with documented right-to-left shunt (RLS) after Valsalva manoeuvre (VM) during transoesophageal echocardiography (TEE). The patients had an average PFO diameter of 6 +/- 2 mm at TEE and an average of 23 +/- 4 microembolic signals (MES) in power M-mode transcranial Doppler sonography (pm-TCD), measured over the middle cerebral artery. An atrial septal aneurysm (ASA) was present in 7 patients (44%). Balloon measurement, performed in all patients, revealed a stretched PFO diameter of 8 +/- 3 mm. In 2 patients (stretched diameter 11 and 14 mm respectively, both with ASA >10 mm), radiofrequency was not applied (PFO too large) and the PFO was closed with an Amplatzer PFO occluder instead. A 6-month follow-up TEE was performed in all patients. There were no serious adverse events during the procedure or at follow-up (12 months average). TEE 6 months after the first RFE procedure showed complete closure of the PFO in 50% of the patients (7/14). Closure appeared to be influenced by PFO diameter, complete closure being achieved in 89% (7/8) with a balloon-stretched diameter < or =7 mm but in none of the patients >7 mm. Only one of the complete closure patients had an ASA. Of the remainder, 4 (29%) had an ASA. Although the PFO was not completely closed in this group, some reduction in the diameter of the PFO and in MES was documented by TEE and pm-TCD with VM. Five of the 7 residual shunt patients received an Amplatzer PFO occluder. Except for one patient with a minimal residual shunt, all showed complete closure of PFO at 6-month follow-up TEE and pm-TCD with VM. The other two refused a closure device. The results confirm that radiofrequency closure of the PFO is safe albeit less efficacious and more complex than device closure. The technique in its current state should not be attempted in patients with a balloon-stretched PFO diameter >7 mm and an ASA.

Superconducting magnet cooling system

DOEpatents

Vander Arend, Peter C.; Fowler, William B.

1977-01-01

A device is provided for cooling a conductor to the superconducting state. The conductor is positioned within an inner conduit through which is flowing a supercooled liquid coolant in physical contact with the conductor. The inner conduit is positioned within an outer conduit so that an annular open space is formed therebetween. Through the annular space is flowing coolant in the boiling liquid state. Heat generated by the conductor is transferred by convection within the supercooled liquid coolant to the inner wall of the inner conduit and then is removed by the boiling liquid coolant, making the heat removal from the conductor relatively independent of conductor length.

Association of aortic stiffness to brain natriuretic peptide in children before and after device closure of patent ductus arteriosus

PubMed Central

Mahfouz, Ragab A.; Alzaiat, Ahmad; Gad, Marwa

2014-01-01

Objectives We evaluated the influence of device closure for patent ductus arteriosus (PDA) on the aortic stiffness index (ASI) and brain natriuretic peptide (BNP) and their association with cardiac function. Patients and methods ASI and echocardiography assessment before and after treatment (16 ± 9 months) in 48 children with PDA (mean age 10 ± 4.5) and 52 control children (mean age 9.7 ± 4.6). BNP level was measured pre-closure for all children, and was measured six months after closure only for children with PDA. Results ASI was higher in PDA patients than in controls (P < 0.001). ASI correlated with age (P < 0.05), LVEF% (P < 0.01), E/E′ (<0.03), pulmonary artery pressure (P < 0.001), and BNP (P < 0.001). ASI and BNP significantly decreased after closure (P < 0.001). ASI and BNP were independent predictors for post-closure systolic dysfunction (P < 0.001and <0.005, respectively). Receiver operating curve (ROC) analysis showed that ASI ⩾ 13.5, BNP level ⩾75 pg/ml and basal mean pulmonary artery pressure (PAP) ⩾ 23 were powerful predictors for post-closure systolic function. Conclusion ASI is significantly associated with BNP and basal PAP in children with PDA. After device closure, aortic distensibility improved significantly and was associated with significant improvement in both systolic and diastolic functions. ASI can be used for monitoring the course of patients with PDA, and may give opportunities for early intervention. PMID:25544819

Digital micromirror device based ophthalmoscope with concentric circle scanning.

PubMed

Damodaran, Mathi; Vienola, Kari V; Braaf, Boy; Vermeer, Koenraad A; de Boer, Johannes F

2017-05-01

Retinal imaging is demonstrated using a novel scanning light ophthalmoscope based on a digital micromirror device with 810 nm illumination. Concentric circles were used as scan patterns, which facilitated fixation by a human subject for imaging. An annular illumination was implemented in the system to reduce the background caused by corneal reflections and thereby to enhance the signal-to-noise ratio. A 1.9-fold increase in the signal-to-noise ratio was found by using an annular illumination aperture compared to a circular illumination aperture, resulting in a 5-fold increase in imaging speed and a better signal-to-noise ratio compared to our previous system. We tested the imaging performance of our system by performing non-mydriatic imaging on two subjects at a speed of 7 Hz with a maximum 20° (diameter) field of view. The images were shot noise limited and clearly show various anatomical features of the retina with high contrast.

Digital micromirror device based ophthalmoscope with concentric circle scanning

PubMed Central

Damodaran, Mathi; Vienola, Kari V.; Braaf, Boy; Vermeer, Koenraad A.; de Boer, Johannes F.

2017-01-01

Retinal imaging is demonstrated using a novel scanning light ophthalmoscope based on a digital micromirror device with 810 nm illumination. Concentric circles were used as scan patterns, which facilitated fixation by a human subject for imaging. An annular illumination was implemented in the system to reduce the background caused by corneal reflections and thereby to enhance the signal-to-noise ratio. A 1.9-fold increase in the signal-to-noise ratio was found by using an annular illumination aperture compared to a circular illumination aperture, resulting in a 5-fold increase in imaging speed and a better signal-to-noise ratio compared to our previous system. We tested the imaging performance of our system by performing non-mydriatic imaging on two subjects at a speed of 7 Hz with a maximum 20° (diameter) field of view. The images were shot noise limited and clearly show various anatomical features of the retina with high contrast. PMID:28663905

Clinically apparent long-term electric disturbances in the acute and very long-term of patent foramen ovale device-based closure.

PubMed

Rigatelli, Gianluca; Zuin, Marco; Pedon, Luigi; Zecchel, Roberto; Dell'Avvocata, Fabio; Carrozza, Antonio; Zennaro, Marco; Pastore, Gianni; Zanon, Francesco

2017-03-01

Incidence of electrical disturbances in patients submitted to transcatheter patent foramen ovale (PFO) closure has not been fully clarified in a large population. The aim of the study is to assess the incidence of atrial fibrillation, supraventricular tachi-arrhythmias, and atrio-ventricular block in the acute and very long-term follow-up. We reviewed the medical and instrumental data of 1000 consecutive patients (mean age 47.3±17.1years) prospectively enrolled in two centers over a 13-year period (February 1999 to February 2012) for right-to-left (R-to-L) shunt ICE-aided catheter-based closure using different devices. Successful transcatheter PFO closure was achieved in 99.8% of the patients. Implanted devices were: Amplatzer PFO Occluder in 463 patients (46.3%), Amplatzer ASD Cribriform Occluder in 420 patients (42.0%), Premere Occlusion System in 95 patients (9.5%), and Biostar Occluder in 22 patients (2.2%). Postprocedural electrical complications occurred in 5.9% of patients. The only independent predictors of electrophysiological complications were female gender (OR 2.3, 0.5-5.1 [95% CI], p<0.001) and device disk >30mm (OR 5.0, 1.2-7.2 [95% CI], p<0.001). On a mean follow-up of 12 .3±0.6years (minimum 4- maximum 17years), electrical complications occurred in 1.4% of patients including one only case of complete AVB and 5 cases of permanent AF. The only independent predictors were female gender (OR 2.3, 0.5-5.1 [95% CI], p<0.001) and device disk >30mm (OR 5.0, 1.2-7.2 [95% CI], p<0.001). Device-based closure of PFO using different devices, appeared very safe from an electrophysiological point of view with low incidence of electrical disturbances even in the very long-term follow-up. Copyright © 2016 Elsevier Inc. All rights reserved.

Left atrial appendage closure with the Watchman device in patients with a contraindication for oral anticoagulation: the ASAP study (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology).

PubMed

Reddy, Vivek Y; Möbius-Winkler, Sven; Miller, Marc A; Neuzil, Petr; Schuler, Gerhard; Wiebe, Jens; Sick, Peter; Sievert, Horst

2013-06-25

The purpose of this study was to assess the safety and efficacy of left atrial appendage (LAA) closure in nonvalvular atrial fibrillation (AF) patients ineligible for warfarin therapy. The PROTECT AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) trial demonstrated that LAA closure with the Watchman device (Boston Scientific, Natick, Massachusetts) was noninferior to warfarin therapy. However, the PROTECT AF trial only included patients who were candidates for warfarin, and even patients randomly assigned to the LAA closure arm received concomitant warfarin for 6 weeks after Watchman implantation. A multicenter, prospective, nonrandomized study was conducted of LAA closure with the Watchman device in 150 patients with nonvalvular AF and CHADS₂ (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack) score ≥1, who were considered ineligible for warfarin. The primary efficacy endpoint was the combined events of ischemic stroke, hemorrhagic stroke, systemic embolism, and cardiovascular/unexplained death. The mean CHADS₂ score and CHA₂DS₂-VASc (CHADS₂ score plus 2 points for age ≥75 years and 1 point for vascular disease, age 65 to 74 years, or female sex) score were 2.8 ± 1.2 and 4.4 ± 1.7, respectively. History of hemorrhagic/bleeding tendencies (93%) was the most common reason for warfarin ineligibility. Mean duration of follow-up was 14.4 ± 8.6 months. Serious procedure- or device-related safety events occurred in 8.7% of patients (13 of 150 patients). All-cause stroke or systemic embolism occurred in 4 patients (2.3% per year): ischemic stroke in 3 patients (1.7% per year) and hemorrhagic stroke in 1 patient (0.6% per year). This ischemic stroke rate was less than that expected (7.3% per year) based on the CHADS₂ scores of the patient cohort. LAA closure with the Watchman device can be safely performed without a warfarin transition, and is a reasonable alternative to consider for patients at high risk for stroke but with contraindications to systemic oral anticoagulation. (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology [ASAP]; NCT00851578). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Sizing of patent ductus arteriosus in adults for transcatheter closure using the balloon pull-through technique.

PubMed

Shafi, Nabil A; Singh, Gagan D; Smith, Thomas W; Rogers, Jason H

2018-05-01

To describe a novel balloon sizing technique used during adult transcatheter patent ductus arteriosus (PDA) closure. In addition, to determine the clinical and procedural outcomes in six patients who underwent PDA balloon sizing with subsequent deployment of a PDA occluder device. Transcatheter PDA closure in adults has excellent safety and procedural outcomes. However, PDA sizing in adults can be challenging due to variable defect size, high flow state, or anatomical complexity. We describe a series of six cases where the balloon- pull through technique was successfully performed for PDA sizing prior to transcatheter closure. Consecutive adult patients undergoing adult PDA closure at our institution were studied retrospectively. A partially inflated sizing balloon was pulled through the defect from the aorta into the pulmonary artery and the balloon waist diameter was measured. Procedural success and clinical outcomes were obtained. Six adult patients underwent successful balloon pull-through technique for PDA sizing during transcatheter PDA closure, since conventional angiography often gave suboptimal opacification of the defect. All PDAs were treated with closure devices based on balloon PDA sizing with complete closure and no complications. In three patients that underwent preprocedure computed tomography, the balloon size matched the CT derived measurements. The balloon pull-through technique for PDA sizing is a safe and accurate sizing modality in adults undergoing transcatheter PDA closure. © 2017 Wiley Periodicals, Inc.

Closure device for lead-acid batteries

DOEpatents

Ledjeff, Konstantin

1983-01-01

A closure device for lead-acid batteries includes a filter of granulated activated carbon treated to be hydrophobic combined with means for preventing explosion of emitted hydrogen and oxygen gas. The explosion prevention means includes a vertical open-end tube within the closure housing for maintaining a liquid level above side wall openings in an adjacent closed end tube. Gases vent from the battery through a nozzle directed inside the closed end tube against an impingement surface to remove acid droplets. The gases then flow through the side wall openings and the liquid level to quench any possible ignition prior to entering the activated carbon filter. A wick in the activated carbon filter conducts condensed liquid back to the closure housing to replenish the liquid level limited by the open-end tube.

Simultaneous in- and out-of-plane Mitral Valve Annular Force Measurements.

PubMed

Skov, Søren N; Røpcke, Diana M; Telling, Kristine; Ilkjær, Christine; Tjørnild, Marcell J; Nygaard, Hans; Nielsen, Sten L; Jensen, Morten O

2015-06-01

Mitral valve repair with annuloplasty is often favoured over total valve replacement. In order to develop and optimize new annuloplasty ring designs, it is important to study the complex biomechanical behaviour of the valve annulus and the subvalvular apparatus with simultaneous in- and out-of-plane restraining force measurements. A new flat D-shaped mitral valve annular force transducer was developed. The transducer was mounted with strain gauges to measure strain and calibrated to provide simultaneous restraining forces in- and out of the mitral annular plane. The force transducer was implanted and evaluated in an 80 kg porcine experimental model. Accumulation of out-of-plane restraining forces, creating strain in the anterior segment were 0.7 ± 0.0 N (towards apex) and an average force accumulation of 1.5 ± 0.3 N, creating strain in the commissural segments (away from apex). The accumulations of in-plane restraining forces, creating strain on the inner side of the ring were 1.7 ± 0.2 N (away from ring center). A new mitral annular force transducer was successfully developed and evaluated in vivo. The transducer was able to measure forces simultaneously in different planes. Initial indications point towards overall agreement with previous individual force measurements in- and out-of the mitral annular plane. This can provide more detailed insight into the annular force distribution, and could potentially improve the level of evidence based mitral valve repair and support the development of future mitral annuloplasty devices.

[Lung perfusion studies after percutaneous closure of patent ductus arteriosus using the Amplatzer Duct Occluder in children].

PubMed

Parra-Bravo, José Rafael; Apolonio-Martínez, Adriana; Estrada-Loza, María de Jesús; Beirana-Palencia, Luisa Gracia; Ramírez-Portillo, César Iván

2015-01-01

The closure of patent ductus arteriosus with multiple devices has been associated with a reduction in lung perfusion. We evaluated the pulmonary perfusion after percutaneous closure of patent ductus arteriosus with the Amplatzer Duct Occluder device using perfusion lung scan. Thirty patients underwent successful percutaneous patent ductus arteriosus occlusions using the Amplatzer Duct Occluder device were included in this study. Lung perfusion scans were preformed 6 months after the procedure. Peak flow velocities and protrusion of the device were analyzed by Doppler echocardiography. A left lung perfusion<40% was considered abnormal. The device implantation was successful in all patients. Average perfusion of left lung was 44.7±4.9% (37.8-61.4). Five patients (16.6%) showed decreased perfusion of the left lung. Age, low weight, the length of the ductus arteriosus and the minimum and maximum diameter/length of the ductus arteriosus ratio were statistically significant in patients with abnormalities of lung perfusion. It was observed protrusion the device in 6 patients with a higher maximum flow rate in the left pulmonary artery. The left lung perfusion may be compromised after percutaneous closure of patent ductus arteriosus with the Amplatzer Duct Occluder. The increased flow velocity in the origin of the left pulmonary artery can be a poor indicator of reduction in pulmonary perfusion and can occur in the absence of protrusion of the device. Copyright © 2014 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

Hidden (end-on) patent ductus arteriosus: recognition and device closure.

PubMed

Garg, Naveen; Madan, Bevunahalli Kantharaj

2016-02-01

Sometimes, it is difficult to visualize a patent ductus arteriosus and deploy a device in the standard lateral view because of an end-on orientation. The right anterior oblique view may be helpful by separating the ductus arteriosus from the aorta. This study was undertaken to evaluate the incidence of end-on patent ductus arteriosus and the utility of the right anterior oblique view during device closure. Aortography was performed in lateral and right anterior oblique views before, during, and after successful device deployment in 117 consecutive patients. When a ductus arteriosus was not clearly visible in the lateral view due to overlapping by the aorta, it was termed "right anterior oblique view useful". The types of patent ductus arteriosus were A, B, C, and E in 86 (73.5%), 20 (17.1%), 4 (3.4%), and 7 (6.0%) patients, respectively. An end-on ductus arteriosus was present in 24 (20.5%) patients (14 type B, 10 type A). The right anterior oblique view was useful during device closure in 15 (12.8%) cases (all end-on type). Among all cases of end-on patent ductus arteriosus, it was useful in 62.5% (most type B and a few type A). In all of these, the device appeared obliquely oriented and foreshortened in the lateral view but fully profiled in the right anterior oblique view. Recognizing an end-on patent ductus arteriosus and utilizing the right anterior oblique view simplified device closure. For ducts well-profiled in the lateral view, the right anterior oblique view is unnecessary and avoidable. © The Author(s) 2016.

Low coke fuel injector for a gas turbine engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, J.R.

This patent describes a gas turbine carbureting device for disposal in a down-stream flowing compressor discharge air flow. It comprises: a spin chamber defined by a generally annular housing including a closed forward end having a continuous unobstructed inner surface and an open aft end wherein the forward end is upstream of the aft end with respect tot he compressor discharge airflow; at least one exhaust tube having an inlet disposed within the spin chamber wherein the exhaust tube is radially spaced apart from the annular housing and which together with the annular housing forms at least in part amore » first annular air passage leading to the forward end; the housing having a fuel entrance and a swirling air entrance to the first annular air passage and spaced axially apart from each other, and wherein the swirling air entrance and fuel entrance are downstream of the closer forward end with respect to the compressor discharge flow; and wherein the first air passage is formed for flowing swirling air from the swirling air passage to the aft end in an upstream direction with respect to the compressor discharge flow and the exhaust tube inlet is disposed within the swirl chamber so as to reverse the axial direction of the swirling air off the forward end from an upstream direction to a downstream direction through the exhaust tube.« less

Intestinal adhesion to the abdominal wall after skin closure with octylcyanoacrylate.

PubMed

Chaya, Miguel; Reyes-Cuervo, Humberto; Cruz, Vivian; Barroso, Gerardo; Garcia-León, Fernando

2004-08-01

Octylcyanoacrylate tissue adhesive glue is a wound closure device recently approved by the U.S. Food and Drug Administration. Few complications have been reported regarding the liquid adhesive entering the wound. The following report involves a patient who developed intestinal occlusion secondary to octylcyanoacrylate used for skin closure in laparoscopic surgery.

Closure of patent ductus arteriosus in children, small infants, and premature babies with Amplatzer duct occluder II additional sizes: multicenter study.

PubMed

Sungur, Metin; Karakurt, Cemsit; Ozbarlas, Nazan; Baspinar, Osman

2013-08-01

To evaluate safety and efficacy of closure of patent ductus arteriosus (PDA) with Amplatzer duct occluder II Additional Sizes (ADO II AS) and to report early and midterm results of the device in children and very young symptomatic infants. Retrospective analysis of angiographic data of 60 children from four pediatric cardiology centers. The median patient age and weight were 6.5 (0.5-168) months and 6.8 (1.19-57) kg, respectively. In the study, 26 children had a body weight of ≤ 6 kg. Of these 26 children, 9 had a body weight of ≤ 3 kg. The median narrowest diameter of PDA was 2 (1.2-4) mm. Ductal anatomy was Type A in 29, Type B in 2, Type C in 11, Type D in 1, and Type E in 16 patients, and a residual PDA after surgery in 1 patient. Closure with ADO II AS was achieved in 58 (96.6%) of 60 attempted cases. In two infants, the device was not released because of significant residual shunt. ADO II was used in one, and the other was sent to surgery. Complete closure was observed in all ADO II AS deployed children by the next day on echocardiography. Median follow-up was 12 (1-18) months. Neither death nor any major complications occurred. Our study shows that closure of medium and small sized PDA by using ADO II AS device is effective and safe in children. The use of the device will expand the field of application of PDA closure in small infants. © 2013 Wiley Periodicals, Inc.

Percutaneous closure of patent foramen ovale in patients with cryptogenic embolism: a network meta-analysis.

PubMed

Stortecky, Stefan; da Costa, Bruno R; Mattle, Heinrich P; Carroll, John; Hornung, Marius; Sievert, Horst; Trelle, Sven; Windecker, Stephan; Meier, Bernhard; Jüni, Peter

2015-01-07

Up to 40% of ischaemic strokes are cryptogenic. A strong association between cryptogenic stroke and the prevalence of patent foramen ovale (PFO) suggests paradoxical embolism via PFO as a potential cause. Randomized trials failed to demonstrate superiority of PFO closure over medical therapy. Randomized trials comparing percutaneous PFO closure against medical therapy or devices head-to-head published or presented by March 2013 were identified through a systematic search. We performed a network meta-analysis to determine the effectiveness and safety of PFO closure with different devices when compared with medical therapy. We included four randomized trials (2963 patients with 9309 patient-years). Investigated devices were Amplatzer (AMP), STARFlex (STF), and HELEX (HLX). Patients allocated to PFO closure with AMP were less likely to experience a stroke than patients allocated to medical therapy [rate ratio (RR) 0.39; 95% CI: 0.17-0.84]. No significant differences were found for STF (RR 1.01; 95% CI: 0.44-2.41), and HLX (RR, 0.71; 95% CI: 0.17-2.78) when compared with medical therapy. The probability to be best in preventing strokes was 77.1% for AMP, 20.9% for HLX, 1.7% for STF, and 0.4% for medical therapy. No significant differences were found for transient ischaemic attack and death. The risk of new-onset atrial fibrillation was more pronounced for STF (RR 7.67; 95% CI: 3.25-19.63), than AMP (RR 2.14; 95% CI: 1.00-4.62) and HLX (RR 1.33; 95%-CI 0.33-4.50), when compared with medical therapy. The effectiveness of PFO closure depends on the device used. PFO closure with AMP appears superior to medical therapy in preventing strokes in patients with cryptogenic embolism. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Rationale and design of a randomised clinical trial comparing vascular closure device and manual compression to achieve haemostasis after diagnostic coronary angiography: the Instrumental Sealing of ARterial puncture site - CLOSURE device versus manual compression (ISAR-CLOSURE) trial.

PubMed

Xhepa, Erion; Byrne, Robert A; Schulz, Stefanie; Helde, Sandra; Gewalt, Senta; Cassese, Salvatore; Linhardt, Maryam; Ibrahim, Tareq; Mehilli, Julinda; Hoppe, Katharina; Grupp, Katharina; Kufner, Sebastian; Böttiger, Corinna; Hoppmann, Petra; Burgdorf, Christof; Fusaro, Massimiliano; Ott, Ilka; Schneider, Simon; Hengstenberg, Christian; Schunkert, Heribert; Laugwitz, Karl-Ludwig; Kastrati, Adnan

2014-06-01

Vascular closure devices (VCD) have been introduced into clinical practice with the aim of increasing the procedural efficiency and clinical safety of coronary angiography. However, clinical studies comparing VCD and manual compression have yielded mixed results, and large randomised clinical trials comparing the two strategies are missing. Moreover, comparative efficacy studies between different VCD in routine clinical use are lacking. The Instrumental Sealing of ARterial puncture site - CLOSURE device versus manual compression (ISAR-CLOSURE) trial is a prospective, randomised clinical trial designed to compare the outcomes associated with the use of VCD or manual compression to achieve femoral haemostasis. The test hypothesis is that femoral haemostasis after coronary angiography achieved using VCD is not inferior to manual compression in terms of access-site-related vascular complications. Patients undergoing coronary angiography via the common femoral artery will be randomised in a 1:1:1 fashion to receive FemoSeal VCD, EXOSEAL VCD or manual compression. The primary endpoint is the incidence of the composite of arterial access-related complications (haematoma ≥5 cm, pseudoaneurysm, arteriovenous fistula, access-site-related bleeding, acute ipsilateral leg ischaemia, the need for vascular surgical/interventional treatment or documented local infection) at 30 days after randomisation. According to power calculations based on non-inferiority hypothesis testing, enrolment of 4,500 patients is planned. The trial is registered at www.clinicaltrials.gov (study identifier: NCT01389375). The safety of VCD as compared to manual compression in patients undergoing transfemoral coronary angiography remains an issue of clinical equipoise. The aim of the ISAR-CLOSURE trial is to assess whether femoral haemostasis achieved through the use of VCD is non-inferior to manual compression in terms of access-site-related vascular complications.

Comparison of three patent foramen ovale closure devices in a randomized trial (Amplatzer versus CardioSEAL-STARflex versus Helex occluder).

PubMed

Taaffe, Margaret; Fischer, Evelyn; Baranowski, Andreas; Majunke, Nicolas; Heinisch, Corinna; Leetz, Michaela; Hein, Ralph; Bayard, Yves; Büscheck, Franziska; Reschke, Madlen; Hoffmann, Ilona; Wunderlich, Nina; Wilson, Neil; Sievert, Horst

2008-05-01

This randomized trial compared procedural complications and 30-day clinical outcomes of 3 patent foramen ovale (PFO) closure devices (Amplatzer, Helex, and CardioSEAL-STARflex). It examined 660 patients (361 men, 299 women, mean age 49.3+/-1.9 years), with 220 patients per group. All patients had a history of paradoxical embolism. All PFO closures were successful technically. Exchange of devices for others was most frequently required for the Helex occluder (7 of 220) and 2 of 220 in either of the other groups. Three device embolizations in the Helex group were retrieved and replaced successfully. One patient with a Helex occluder developed a transient ischemic attack and recovered without treatment. A hemopericardium in that group was punctured without affecting the device. One tamponade in the Amplatzer group required surgical device explantation. In 8 of 660 patients in the CardioSEAL-STARflex group, thrombi resolved after anticoagulation. Sixteen patients (11 in the CardioSEAL-STARflex group, 3 in the Amplatzer group, and 2 in the Helex group) had episodes of atrial fibrillation. PFOs were closed completely in 143 of 220 patients (65%) in the Amplatzer group, 116 of 220 patients (52.7%) in the Helex group, and 137 of 220 patients (62.3%) in the CardioSEAL-STARflex group at 30 days with significant differences between the Helex and Amplatzer occluders (p=0.0005) and the Helex and CardioSEAL-STARflex occluders (p=0.0003). PFO closure can be performed safely with each device. In conclusion, the Helex occluder embolized more frequently. Device thrombus formation and paroxysmal atrial fibrillation were more common with the CardioSEAL-STARflex occluder.

Biomechanical Testing and Histologic Examination of Intradermal Skin Closure in Dogs Using Barbed Suture Device and Non-Barbed Monofilament Suture.

PubMed

Law, Andy Y; Butler, James R; Patnaik, Sourav S; Cooley, James A; Elder, Steven H

2017-01-01

To compare the biomechanical strength and histologic features of 3-0 Glycomer™ 631 barbed suture (V-LOC™ 90 Absorbable Wound Closure Device, Covidien, Mansfield, MA) to non-barbed 3-0 Glycomer™ 631 suture (Biosyn™, Covidien) for intradermal skin wound closure in the dog. Randomized, factorial, in vivo. Eighteen purpose-bred, mature male, and female hound dogs. Eighteen adult hound dogs were randomly assigned to 1 of 3 groups designated by postoperative day of assessment. Six skin incisions were made along the dorsum in the thoracolumbar region of each dog with an equal number (n=3) randomly assigned to closure with barbed or non-barbed suture. Six dogs were euthanatized on postoperative days 3, 10, and 14, respectively. Two additional incisions were made on each dog after euthanasia for baseline data (Day 0). The skin incision specimens were harvested for biomechanical testing and histologic evaluation. Non-barbed closure had significantly higher maximum load at failure (P<.001) and stiffness (P<.001) than barbed closure regardless of day. The average tissue reaction score was significantly higher for barbed closure (P=.008), regardless of day. Suturing time for barbed closures was significantly shorter. There was no significant difference in frequency of complications between closures. Barbed Glycomer™ 631 closures had a significantly lower maximum load at failure and stiffness, and higher average tissue reaction scores, but showed no difference in short term outcome for intradermal closure of dorsally located skin incisions in dogs. © 2016 The American College of Veterinary Surgeons.

Device for temporarily closing duct-formers in well completion apparatus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zandmer, H.M.; Zandmer, S.M.

A duct-forming device is disclosed for use in a well completion apparatus of the kind, wherein a bore hole casing is positioned in a bore hole and duct-forming devices of alkali- and acid resistant metal-such as steel-are secured at spaced levels to the casing in alignment with holes machined in the casing wall. In accordance with the invention, a closure device is arranged within the duct-forming device which permits flow of predetermined amounts of liquid, such as acid, from the interior of the casing through the duct-forming device and into the producing formation, while gradually being moved by the liquidmore » into a position in which such fluid flow is prevented. After the fluid flow has been stopped by the closure device and when the formation pressure exceeds the pressure within the duct-forming device and the casing, fluid from the formation then forces the closure device toward and into the casing space to permit thereafter free flow of formation fluid into the duct-forming device and the casing or of pressurized treatment liquid from the casing into the formation. The inventive arrangement permits inter alia the establishment of a sufficient and substantially uniform feeding rate of treatment liquid, such as acid, from the casing into the producing formation through all the duct-formers in preparation for subsequent acidification or other treatments, such as sand fracking.« less

Cost-Effectiveness of Percutaneous Closure of the Left Atrial Appendage in Atrial Fibrillation Based on Results From PROTECT AF Versus PREVAIL.

PubMed

Freeman, James V; Hutton, David W; Barnes, Geoffrey D; Zhu, Ruo P; Owens, Douglas K; Garber, Alan M; Go, Alan S; Hlatky, Mark A; Heidenreich, Paul A; Wang, Paul J; Al-Ahmad, Amin; Turakhia, Mintu P

2016-06-01

Randomized trials of left atrial appendage (LAA) closure with the Watchman device have shown varying results, and its cost effectiveness compared with anticoagulation has not been evaluated using all available contemporary trial data. We used a Markov decision model to estimate lifetime quality-adjusted survival, costs, and cost effectiveness of LAA closure with Watchman, compared directly with warfarin and indirectly with dabigatran, using data from the long-term (mean 3.8 year) follow-up of Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation (PROTECT AF) and Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation (PREVAIL) randomized trials. Using data from PROTECT AF, the incremental cost-effectiveness ratios compared with warfarin and dabigatran were $20 486 and $23 422 per quality-adjusted life year, respectively. Using data from PREVAIL, LAA closure was dominated by warfarin and dabigatran, meaning that it was less effective (8.44, 8.54, and 8.59 quality-adjusted life years, respectively) and more costly. At a willingness-to-pay threshold of $50 000 per quality-adjusted life year, LAA closure was cost effective 90% and 9% of the time under PROTECT AF and PREVAIL assumptions, respectively. These results were sensitive to the rates of ischemic stroke and intracranial hemorrhage for LAA closure and medical anticoagulation. Using data from the PROTECT AF trial, LAA closure with the Watchman device was cost effective; using PREVAIL trial data, Watchman was more costly and less effective than warfarin and dabigatran. PROTECT AF enrolled more patients and has substantially longer follow-up time, allowing greater statistical certainty with the cost-effectiveness results. However, longer-term trial results and postmarketing surveillance of major adverse events will be vital to determining the value of the Watchman in clinical practice. © 2016 American Heart Association, Inc.

Long-term outcomes of patent foramen ovale closure or medical therapy after cryptogenic stroke: A meta-analysis of randomized trials.

PubMed

Abdelaziz, Hesham K; Saad, Marwan; Abuomara, Hossamaldin Z; Nairooz, Ramez; Pothineni, Naga Venkata K; Madmani, Mohamed E; Roberts, David H; Mahmud, Ehtisham

2018-05-04

To examine long-term clinical outcomes with transcatheter patent foramen ovale (PFO) closure versus medical therapy alone in patients with cryptogenic stroke. A long-standing debate regarding the optimal approach for the management of patients with PFO after a cryptogenic stroke exists. An electronic search was performed for randomized clinical trials (RCTs) reporting clinical outcomes with PFO closure vs. medical therapy alone after stroke. Random effects DerSimonian-Laird risk ratios (RR) were calculated. The main outcome was recurrence of stroke. Other outcomes included transient ischemic attack (TIA), new-onset atrial fibrillation/flutter (AF/AFL), major bleeding, serious adverse events, and device-related complications. All-cause mortality was also examined. Five RCTs with a total of 3,440 patients were included. At a mean follow-up of 4.02 ± 1.57 years, PFO closure was associated with less recurrence of stroke (RR = 0.43; 95% CI 0.19-0.91; P = .027) compared with medical therapy alone. No difference was observed between both strategies for TIA (P = .21), major bleeding (P = .69), serious adverse events (P = .35), and all-cause death (P = .48). However, PFO closure, was associated with increased new-onset AF/AFL (P < .001), risk of pulmonary embolism (P = .04), and device-related complications (P < .001). On a subgroup analysis, stroke recurrence rate remained lower in PFO closure arm regardless of the type of closure device used (P interaction  = .50), or the presence of substantial shunt in the majority of study population (P interaction  = .13). Transcatheter PFO closure reduces the recurrence of stroke compared with medical therapy alone, with no significant safety concerns. Close follow-up of patients after PFO closure is recommended to detect new-onset atrial arrhythmias. © 2018 Wiley Periodicals, Inc.

Extradiscal ultrasound thermal therapy (ExDUSTT): evaluation in ex vivo and in vivo spine models (Invited Paper)

NASA Astrophysics Data System (ADS)

Diederich, Chris J.; Kinsey, Adam; Nau, William H.; Shu, Richard; Lotz, Jeffrey C.

2005-04-01

The application of heat to intervertebral discs is being clinically investigated for the treatment of discogenic back pain. The purpose of this study was to develop and test the feasibility of small ultrasound applicators that can be endoscopically placed adjacent to the disc, and deliver heating energy into the disc without puncturing the annular wall. Prototype devices were fabricated using curvilinear transducers (2.5-3.5 mm wide x 10 mm long, 5.4 - 6.5 MHz) that produce a narrow penetrating beam extending along the length of the ultrasound element. The transducer was affixed to either a flexible or rigid delivery catheter, and enclosed within an asymmetric coupling balloon with water-cooling flow. Bench measurements demonstrated 35-60% acoustic efficiencies, high-power output capabilities, and lightly focused beam patterns. The heating characteristics of these devices were evaluated with ex vivo and in vivo experiments within lumbar and cervical spine segments from sheep models and human cadaveric spine. The applicators were positioned adjacent to the annular wall of the surgically exposed discs. Ultrasound energy was focused directly into the disc to avoid heating the vertebral bodies. Multi-point thermocouple probes were placed throughout the disc to characterize the resultant temperature distributions. These studies demonstrated that ultrasound energy from these applicators penetrated the annular wall of the disc, and produced thermal coagulative temperatures of >60-65°C as far as 10 mm into the tissue. This study also showed that lower power levels and temperatures delivered for 10 minutes can generate a cytotoxic thermal dose of t43°C >240 min penetrating 5-10 mm from the annular wall.

Intra-operative device closure of perimembranous ventricular septal defect without cardiopulmonary bypass under guidance of trans-epicardial echocardiography: a single center experience.

PubMed

Sun, Yong; Zhu, Peng; Zhou, Pengyu; Guo, Yilong; Zheng, Shao-Yi

2016-05-27

Intraoperative device closure of perimembranous ventricular septal defect(VSD) through a lower mini-sternotomy is safe, less invasive, and has excellent surgical and cosmetic outcomes. Our study is to evaluate the feasibility of closing VSD under guidance of trans-epicardial echocardiography. We reviewed the clinical course of 41 patients referred to our institution for minimally invasive closure of perimembranous VSD. The trans-epicardial echocardiography(TEE) was used to monitor the whole procedure to guide the positioning of device and evaluate the operative effect instantly after operation. The procedure was successfully done in 38 patients(92.6 %) with mean age of 1.2 ± 1.5 years(range 0.5-6.1 years),mean weight of 10.78 ± 6.87 kg(range 5.2 ~ 26 kg) and VSD size of 5.1 ± 1.13 mm(range 5 ~ 10 mm). Three cases failed, including two cases whose guide-wires could not pass through VSDs and one case whose occluder could not repair VSD well. Three patients had tiny residual shunts because of the shifting of occluders. There were no major complications such as arrhythmia, valve regurgitation and the failure of occluder during follow-up(Mean 2.3 ± 1.2 years). TEE provided superior imaging of shapes and surrounding structures of the VSDs, and guide-wires passing through VSDs. Intraoperative device closure of perimembranous VSD through a lower mini-sternotomy without cardiopulmonary bypass appears to be a safe and effective procedure. The use of trans-epicardial echocardiography provides useful information for intraoperative device closure of VSD.

Design and rationale of the AngioSeal versus the Radial approach In acute coronary SyndromE (ARISE) trial: a randomized comparison of a vascular closure device versus the radial approach to prevent vascular access site complications in non-ST-segment elevation acute coronary syndrome patients.

PubMed

de Andrade, Pedro Beraldo; E Mattos, Luiz Alberto Piva; Tebet, Marden André; Rinaldi, Fábio Salerno; Esteves, Vinícius Cardozo; Nogueira, Ederlon Ferreira; França, João Ítalo Dias; de Andrade, Mônica Vieira Athanazio; Barbosa, Robson Alves; Labrunie, André; Abizaid, Alexandre Antônio Cunha; Sousa, Amanda Guerra de Moraes Rego

2013-12-18

Arterial access is a major site of bleeding complications after invasive coronary procedures. Among strategies to decrease vascular complications, the radial approach is an established one. Vascular closure devices provide more comfort to patients and decrease hemostasis and need for bed rest. However, the inconsistency of data proving their safety limits their routine adoption as a strategy to prevent vascular complications, requiring evidence through adequately designed randomized trials. The aim of this study is to compare the radial versus femoral approach using a vascular closure device for the incidence of arterial puncture site vascular complications among non-ST-segment elevation acute coronary syndrome patients submitted to an early invasive strategy. ARISE is a national, multicenter, non-inferiority randomized clinical trial. Two hundred patients with non-ST-segment elevation acute coronary syndrome will be randomized to either radial or femoral access using a vascular closure device. The primary outcome is the occurrence of vascular complications at an arterial puncture site 30 days after the procedure, including major bleeding, retroperitoneal hematoma, compartment syndrome, hematoma ≥ 5 cm, pseudoaneurysm, arterio-venous fistula, infection, limb ischemia, arterial occlusion, adjacent nerve injury or the need for vascular surgical repair. Enrollment was initiated in September 2012, and until October 2013 91 patients were included. The inclusion phase is expected to last until the second half of 2014. The ARISE trial will help define the role of a vascular closure device as a bleeding avoidance strategy in patients with NSTEACS. ClinicalTrials.gov identifier: NCT01653587.

Percutaneous closure of patent foramen ovale without echocardiographic guidance.

PubMed

Jamshidi, Peiman; Wahl, Andreas; Windecker, Stephan; Schwerzmann, Markus; Seiler, Christian; Meier, Bernhard

2007-01-01

A percutaneous patent foramen ovale (PFO) closure procedure includes transesophageal or intracardiac echocardiographic guidance at many centers. We investigated the feasibility and complications of the PFO closure without echocardiography. A total of 420 consecutive patients (185 women and 235 men, mean age 51 +/- 12 years) underwent percutaneous PFO closure without echocardiographic guidance using 7 different devices. Of these, 106 patients (25%) had an associated atrial septal aneurysm. The implantation was successful in 418 patients (99%). There were 12 procedural complications (3%), including embolization of the device or of parts of it with successful percutaneous removal in 5 cases, pericardial tamponade requiring pericardiocentesis in 1 patient, air embolism with transient symptoms in 3 patients, and vascular access problems in 3 patients. In none of the cases, echocardiography had to be summoned during the case or its lack was associated with acute or subsequent problems. The fluoroscopy time and procedure time were 5.4 +/- 2.7 and 25 +/- 17 minutes, respectively. Transthoracic contrast echocardiography, 24 hours after device implantation, detected a residual shunt in 19% of the patients. Percutaneous PFO closure with fluoroscopic guidance only is feasible and has low complication rates, especially with Amplatzer PFO Occluders. The added time and cost of echocardiography during the procedure is not warranted.

Catheter closure of patent foramen ovale in patients with cryptogenic cerebrovascular accidents: initial experiences in Japan.

PubMed

Kijima, Yasufumi; Akagi, Teiji; Nakagawa, Koji; Taniguchi, Manabu; Ueoka, Akira; Deguchi, Kentaro; Toh, Norihisa; Oe, Hiroki; Kusano, Kengo; Sano, Shunji; Ito, Hiroshi

2014-01-01

Although numerous studies have shown an association between a patent foramen ovale (PFO) and cryptogenic cerebrovascular accidents (CVA), there has been no definitive control study that demonstrated the benefit of percutaneous device closure of a PFO compared to medical therapy in patients with CVA. Additionally, few clinical data exist for Japanese patients in this field. We demonstrate the initial experiences in catheter closure of a PFO as secondary prevention of CVA in Japan. Catheter closure of a PFO was attempted in 7 patients who were diagnosed with cryptogenic CVA. Mean age at the procedure was 54 ± 19 years. The presence of spontaneous interatrial right-to-left shunts was demonstrated by transesophageal contrast echocardiography without Valsalva maneuver in all of the patients. Amplatzer Cribriform device (n = 4) or Amplatzer PFO Occluder (n = 3) was used for the procedure and was successfully deployed. Device-related complications were not observed at the time of the procedure or during the follow-up period (mean period of 16 ± 9 months). Catheter closure of a PFO could be safely performed with Amplatzer Cribriform or Amplatzer PFO Occluder. This procedure may contribute to prevention of recurrent cryptogenic CVA in Japanese patients.

[Right patent ductus arteriosus with an ipsilateral aortic arch: percutaneous closure with amplatzer devices].

PubMed

Santiago, Justo; Acuña, Manuel; Arispe, Elizabeth; Camargo, Ronaldo; Neves, Juliana; Arnoni, Daniel; Fontes, Valmir F; Pedra, Carlos A

2007-03-01

The association of a right aortic arch with an ipsilateral patent ductus arteriosus is rare, especially when there are no other intracardiac anomalies. We report three female patients aged 26, 35 and 9 years with this combination in whom previous attempts at surgical closure by thoracotomy and sternotomy were unsuccessful and who subsequently underwent successful percutaneous closure of the defects using Amplatzer devices. In two patients, although angiography demonstrated the presence of type-A patent ductus arteriosus, it was not possible to determine the minimum diameter accurately and it was necessary to measure it using a sizing balloon. An Amplatzer duct occluder was used in two patients and an Amplatzer muscular ventricular septal defect occluder, in the other. In all patients, full closure was confirmed in the catheterization laboratory and the patients were discharged on the same day with no complications. Percutaneous closure of a right patent ductus arteriosus associated with a right aortic arch is feasible, safe and effective.

Stent-Grafts in the Management of Hemorrhagic Complications Related to Hemostatic Closure Devices: Report of Two Cases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giansante Abud, Daniel; Mounayer, Charbel; Saint-Maurice, Jean Pierre

We report 2 cases of hemorrhagic complications related to use of the Angio-Seal hemostatic closure device that were successfully managed with stent-grafts. Two patients with subarachnoid hemorrhage were referred to our departments for endovascular treatment of ruptured intracranial aneurysms. The treatment was performed through a femoral access; the sheaths were removed immediately after the procedures, and the punctures sites closed by Angio-Seals. Both patients presented clinical signs of hypovolemic shock after treatment. The diagnosis of active bleeding through the puncture site was made by emergency digital subtraction angiography. The lesions were managed with stent-grafts. The use of stent-grafts proved tomore » be efficient in the management of these life-threatening hemorrhagic complications following the use of the Angio-Seal hemostatic closure device.« less

Patient Satisfaction After Femoral Arterial Access Site Closure Using the ExoSeal{sup ®} Vascular Closure Device Compared to Manual Compression: A Prospective Intra-individual Comparative Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pieper, Claus Christian, E-mail: claus.christian.pieper@ukb.uni-bonn.de; Thomas, Daniel, E-mail: daniel.thomas@ukb.uni-bonn.de; Nadal, Jennifer, E-mail: jennifer.nadal@ukb.uni-bonn.de

PurposeTo intra-individually compare discomfort levels and patient satisfaction after arterial access closure using the ExoSeal{sup ®} vascular closure device (VCD) and manual compression (MC) in a prospective study design.MethodsPatients undergoing two planned interventions from 07/2013 to 09/2014 could participate in the study. Access closure was performed with an ExoSeal{sup ®}-VCD in one and MC in the other intervention. Patients were clinically and sonographically examined and were given questionnaires 1 day after intervention [groin- and back-pain during bedrest (100-point visual analog scale; 0: no pain); comfortability of bedrest (10-point Likert scale, 1: comfortable), satisfaction with closure (10-point Likert scale, 1: very satisfied)].more » Results were analyzed in a cross-over design.Results48 patients (29 male, median age 62.5 (32–88) years) were included. An ExoSeal{sup ®}-VCD was used first in 25 cases. As four of these subsequently refused MC as second intervention, data from 44 patients could be analyzed. All closures were technically successful (successful device deployment) without major complications. Groin- and back-pain after VCD-use/MC was 0 (0–15) vs. 10 (0–80) and 0 (0–75) vs. 25 (0–90), respectively (p < 0.0001). Bedrest after VCD-use was more comfortable than after MC [1 (range 1–7) vs. 6 (2–10); p < 0.0001]. Satisfaction with the closure procedure and with the intervention in general was higher after VCD-use compared to MC [1 (1–3) vs. 5 (2–10) and 1 (1–2) vs. 2 (1–4), respectively; p < 0.0001].ConclusionIntra-individual comparison showed pain levels and discomfort to be significantly lower after ExoSeal{sup ®} use compared to MC. VCD closure was associated with higher satisfaction both with the closure itself and with the intervention in general.« less

Outcomes of mechanical stapling for postlaryngectomy open pharyngotomy closure.

PubMed

Paddle, Paul; Husain, Inna; McHugh, Lauren; Franco, Ramon

2017-03-01

A total laryngectomy (TL) is performed as a primary or salvage therapy for laryngeal carcinoma. Pharyngotomy closure after TL is typically performed using manual sutures. Automatic stapling devices are routinely used in thoracoabdominal surgery, but have not been widely accepted for use in pharyngotomy closure. Previously described closed stapling techniques of pharyngeal closure do not allow direct evaluation of surgical margins and are limited to endolaryngeal disease. We describe an open technique for pharyngotomy closure using a mechanical stapling device. Retrospective review. A review was conducted of 16 total laryngectomies performed from May 2008 to August 2015 utilizing an Ethicon Endopath ETS Compact-Flex 45 stapler. Sixteen patients (15 male, one female), mean age 69 years, received open TL (14 salvage, two primary) with endostapler pharyngeal closure and primary tracheoesophageal puncture (TEP). Surgical time averaged 218 minutes. Median time to swallowing was 4 days (range, 2-240 days) and mean hospital stay 6 days (range, 3-10 days). Fistula incidence was 31% (5/16) overall and 36% (5/14) in the postradiation patients. Mechanical stapling is a simple method for postlaryngectomy open pharyngotomy closure. This technique allows evaluation of margins, easy primary TEP, and the opportunity for early swallowing and shorter hospital stays. In addition, it can be performed for closure of salvage laryngectomies with rates of fistula formation similar to that found in the literature using suture closure techniques. Future studies are necessary to compare oncological results and surgical complications between the open and closed stapling techniques and to traditional suture closure. 4 Laryngoscope, 127:605-610, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Efficient semiconductor light-emitting device and method

DOEpatents

Choquette, Kent D.; Lear, Kevin L.; Schneider, Jr., Richard P.

1996-01-01

A semiconductor light-emitting device and method. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL).

Efficient semiconductor light-emitting device and method

DOEpatents

Choquette, K.D.; Lear, K.L.; Schneider, R.P. Jr.

1996-02-20

A semiconductor light-emitting device and method are disclosed. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL). 12 figs.

Primary limited lumbar discectomy with an annulus closure device: one-year clinical and radiographic results from a prospective, multi-center study.

PubMed

Lequin, Michiel B; Barth, Martin; Thomė, Claudius; Bouma, Gerrit J

2012-12-01

Discectomy as a treatment for herniated lumbar discs results in outcomes after surgery that are not uniformly positive. Surgeons face the dilemma between limited nucleus removal which is associated with a higher risk of recurrence, or more aggressive nucleus removal which may lead to disc height loss and persistent back-pain. annulus closure devices may allow for the benefits of limited nucleus removal without the increased risk of recurrence. This is an interim report of an ongoing 24-month post-marketing study of the Barricaid® annulus closure device, consisting of a flexible polymer mesh that blocks the defect, held in place by a titanium bone anchor. We prospectively enrolled 45 patients at four hospitals, and implanted the Barricaid® after a limited discectomy. annulus defect size and volume of removed nucleus were recorded. Reherniations were reported, pain and function were monitored and imaging was performed at regular intervals during 24 months of follow-up. At 12 months postsurgery, pain and function were significantly improved, comparing favorably to reported results from limited discectomy. Disc height has been well maintained. One reherniation has occurred (2.4%), which was associated with a misplaced device. No device fracture, subsidence or migration has been observed. The use of an annulus closure device may provide a reduction in reherniation rate for lumbar discectomy patients with large annulus defects who are at the greatest risk of recurrence. Using such a device should provide the surgeon increased confidence in minimizing nucleus removal, which, in turn, may preserve disc height and biomechanics, reducing degeneration and associated poor clinical outcomes in the long-term. A randomized multicenter study evaluating limited discectomy with and without the Barricaid® is currently underway, and will provide a higher level of evidence.

Efficacy and safety of percutaneous left atrial appendage closure to prevent thromboembolic events in atrial fibrillation patients with high stroke and bleeding risk.

PubMed

Seeger, Julia; Bothner, Carlo; Dahme, Tillman; Gonska, Birgid; Scharnbeck, Dominik; Markovic, Sinisa; Rottbauer, Wolfgang; Wöhrle, Jochen

2016-03-01

The randomized PROTECT AF trial demonstrated non-inferiority of left atrial appendage (LAA) closure to oral anticoagulation with warfarin. Current guidelines give a class IIb recommendation for LAA closure. We evaluated the efficacy and safety of LAA closure in a consecutive series of non-valvular atrial fibrillation patients with contraindications to long-term oral anticoagulation or at high bleeding risk. 101 consecutive non-valvular atrial fibrillation patients (age 74.7 ± 7.5 years) at high risk for stroke (CHA2DS2-VASc Score 4.4 ± 1.6) and high bleeding risk (HAS-BLED Score 4.2 ± 1.3) received LAA closure with either the Watchman closure device (n = 38) or the Amplatzer cardiac plug (n = 63). Dual antiplatelet therapy with aspirin and clopidogrel was recommended for 3-6 months after device implantation, followed by long-term antiplatelet therapy with aspirin. No anticoagulation was given after device implantation. Mean follow-up was 400 days. One patient (1 %) experienced a transient ischemic attack, and two patients (2 %) suffered from ischemic stroke. While on recommended antiplatelet therapy, bleeding occurred in 12/101 patients (12 %). Bleeding was significantly reduced with 3 compared with 6 months dual antiplatelet therapy (3.0 vs. 16.2 %, p < 0.05) while ischemic or thrombotic events were similar. Left atrial appendage closure in patients with non-valvular atrial fibrillation and high risk for stroke and bleeding events effectively prevented stroke and reduced cerebral ischemic events compared to expected stroke rate according to CHA2DS2-VASc Score. Dual antiplatelet therapy for 3 months reduced the rate of bleeding events compared to 6 months therapy with no increase of thrombotic events.

Coherent Structures and Chaos Control in High-Power Microwave Devices

DTIC Science & Technology

2006-06-29

Theory of Multiresonator Cylindrical Magnetrons 2. High - Power Klystron Research 9 2.1. Determination of the Current Limit on the Confinement of Finite...Size Bunched Pencil Beams in High - Power Relativistic Klystrons 2.2. Exploration of the Possibility of Magnetic Cusp Formation in Highly Bunched...Annular Beams in High - Power Relativistic Klystrons 3. Development of Ellipse-Shaped Ribbon-Beam Theory for HPM Device Applications 12 3.1. Theory of

Mitral leaflet geometry perturbations with papillary muscle displacement and annular dilatation: an in-vitro study of ischemic mitral regurgitation.

PubMed

He, Shengqiu; Jimenez, Jorge; He, Zhaoming; Yoganathan, Ajit P

2003-05-01

Perturbations of leaflet geometry are the final end point through which left ventricular (LV) ischemia causes incomplete mitral leaflet closure and resultant mitral regurgitation (MR). Geometric inconsistencies observed with valvular or subvalvular structural alterations raise several questions. A new in-vitro LV flexible bag model was developed in order to visualize and analyze leaflet geometric changes under simulated pathological ischemic MR conditions. Papillary muscle (PM) displacement and annular dilatation decreased leaflet coaptation length, leading to significant MR. Symmetrical PM displacement shifted the coaptation line towards the leaflet edges and created central gaps along this line. Asymmetric PM displacement generated diametrically uneven coaptation with a tent-shaped leaflet at the tethered PM side, while the leaflet bulged at the opposite side towards the left atrium. Leaflet geometry during systole is affected by subvalvular structures. Asymmetric PM displacement, which may occur in regional or acute myocardial infarction, induces irregular deformation of the leaflet's coaptation line and, as a result, MR at the tethered side. Direct visualization of leaflet perturbation under these simulated pathological conditions may promote understanding of mechanisms present in ischemic MR.

Percutaneous closure of patent ductus arteriosus in children using amplatzer duct occluder II: relationship between PDA type and risk of device protrusion into the descending aorta.

PubMed

Masri, Samer; El Rassi, Issam; Arabi, Mariam; Tabbakh, Anas; Bitar, Fadi

2015-08-01

To compare the efficacy and safety of Amplatzer Duct Occluder II (ADOII) among the various patent ductus arteriosus (PDA) types, and to assess the association between development of aortic obstruction and the PDA type in terms of measurable parameters as the device angulation and distance of upper end protrusion into the aortic lumen. Retrospective cohort study involving 50 consecutive subjects who underwent ADO II device closure of PDA. The median age and weight at intervention were 13 months (5.5 months to 18 years) and 11 (6-67) kg respectively. The median smallest ductal diameter by angiography was 3.2 (1.9-5.4) mm. Thirty two patients had type A PDA, 5 had type C, 5 had type D, and 8 had type E. Residual shunt was seen in only 1 patient who had a tubular PDA and resolved within 2 months of the procedure. No device embolization or pulmonary side protrusion were noted. There was a 16% aortic protrusion rate. The median distance of protrusion of the upper end of the device into the aortic lumen was 3.1 (0-9) mm and the median angle formed between the aortic end of the device and the PDA take-off was 10.4 (0-80.6) degrees. These latter parameters of aortic obstruction were significantly higher in the non-conical PDA group as compared to the conical PDA. Nevertheless, there was no significant coarctation due to aortic retention disc protrusion. Device closure of PDA using the ADO II is a safe procedure for chosen types of PDA. We demonstrated a novel technique for objective assessment of device protrusion into the descending aorta based on measurable parameters. ADOII device closure of non-conical PDAs warrants closer follow ups. © 2015 Wiley Periodicals, Inc.

A Challenging Case of Patent Ductus Arteriosus Device Closure in an Adult with Unconventional Views and Catheters

PubMed Central

Garg, Naveen; Raja, Deep Chandh; Khanna, Roopali; Kumar, Sudeep

2018-01-01

Abnormally oriented patent ductus arteriosus is expected in adults, which can lead to difficulties while attempting a device closure. Alternate angiographic views like the “right anterior oblique view,” “retrograde approach” and in rare cases, as elicited in the following case scenario, special catheters like the “Tiger® catheter” can aid in crossing the lesion and completion of the procedure successfully. PMID:29876027

A high-throughput three-dimensional cell migration assay for toxicity screening with mobile device-based macroscopic image analysis

PubMed Central

Timm, David M.; Chen, Jianbo; Sing, David; Gage, Jacob A.; Haisler, William L.; Neeley, Shane K.; Raphael, Robert M.; Dehghani, Mehdi; Rosenblatt, Kevin P.; Killian, T. C.; Tseng, Hubert; Souza, Glauco R.

2013-01-01

There is a growing demand for in vitro assays for toxicity screening in three-dimensional (3D) environments. In this study, 3D cell culture using magnetic levitation was used to create an assay in which cells were patterned into 3D rings that close over time. The rate of closure was determined from time-lapse images taken with a mobile device and related to drug concentration. Rings of human embryonic kidney cells (HEK293) and tracheal smooth muscle cells (SMCs) were tested with ibuprofen and sodium dodecyl sulfate (SDS). Ring closure correlated with the viability and migration of cells in two dimensions (2D). Images taken using a mobile device were similar in analysis to images taken with a microscope. Ring closure may serve as a promising label-free and quantitative assay for high-throughput in vivo toxicity in 3D cultures. PMID:24141454

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Gabriel, E-mail: dr.changabriel@gmail.com; Quek, Lawrence Hwee Han, E-mail: lawrence-quek@ttsh.com.sg; Tan, Glenn Leong Wei, E-mail: glenn-tan@ttsh.com.sg

BackgroundInsertion of a carotid chimney graft during thoracic endovascular aortic repair (Ch-TEVAR) is a recognized technique to extend the proximal landing zone into the aortic arch in the treatment of thoracic aortic disease. Conventional technique requires surgical exposure of the carotid artery for insertion of the carotid chimney graft.MethodologyWe describe our experience in the use of a suture-mediated closure device in percutaneous Ch-TEVAR in four patients.ResultsSuccessful hemostasis was achieved in all four patients. No complications related to the carotid puncture were recorded.ConclusionWe conclude that using suture-mediated closure device for carotid closure appears feasible and deserves further studies as a potentialmore » alternative to conventional surgical approach.« less

Loop-anchor purse-string closure of gastrotomy in NOTES(R) procedures: survival studies in a porcine model.

PubMed

Romanelli, John R; Desilets, David J; Chapman, Christopher N; Surti, Vihar C; Lovewell, Carolanne; Earle, David B

2010-12-01

Transgastric NOTES(®) procedures remain without a simple method to close the gastrotomy. In four survival swine studies, we have tested a novel gastric closure device: the loop-anchor purse-string (LAPS) closure system. In four anesthetized pigs, an endoscopic gastrotomy was performed. Four loop anchors were arrayed in a 2-cm square pattern around the gastrotomy. The endoscope was passed into the abdominal cavity, and the gastrotomy was cinched closed. Procedure times ranged from 50-180 minutes. Three pigs survived 14 days. One animal was sacrificed early due to signs of sepsis. Another animal developed fevers and was treated with antibiotics. At necropsy, there were no abscesses, including in the septic animal. Histologic examination revealed evidence of healing in all animals. The LAPS system holds promise with early success in an animal model. Future human studies are needed to determine viability as a human visceral closure device.

The effect of acute mechanical left ventricular unloading on ovine tricuspid annular size and geometry.

PubMed

Malinowski, Marcin; Wilton, Penny; Khaghani, Asghar; Brown, Michael; Langholz, David; Hooker, Victoria; Eberhart, Lenora; Hooker, Robert L; Timek, Tomasz A

2016-09-01

Left ventricular assist device (LVAD) implantation may alter right ventricular shape and function and lead to tricuspid regurgitation. This in turn has been reported to be a determinant of right ventricular (RV) failure after LVAD implantation, but the effect of mechanical left ventricular (LV) unloading on the tricuspid annulus is unknown. The aim of the study was to provide insight into the effect of LVAD support on tricuspid annular geometry and dynamics that may help to optimize LV unloading with the least deleterious effect on the right-sided geometry. In seven open-chest anaesthetized sheep, nine sonomicrometry crystals were implanted on the right ventricle. Additional nine crystals were implanted around the tricuspid annulus, with one crystal at each commissure defining three separate annular regions: anterior, posterior and septal. Left ventricular unloading was achieved by connecting a cannula in the left atrium and the aorta to a continuous-flow pump. The pump was used for 15 min at a full flow of 3.8 ± 0.3 l/min. Epicardial echocardiography was used to assess the degree of tricuspid insufficiency. Haemodynamic, echocardiographic and sonomicrometry data were collected before and during full unloading. Tricuspid annular area, and the regional and total perimeter were calculated from crystal coordinates, while 3D annular geometry was expressed as the orthogonal distance of each annular crystal to the least squares plane of all annular crystals. There was no significant tricuspid regurgitation observed either before or during LV unloading. Right ventricular free wall to septum diameter increased significantly at end-diastole during unloading from 23.6 ± 5.8 to 26.3 ± 6.5 mm (P = 0.009), but the right ventricular volume, tricuspid annular area and total perimeter did not change from baseline. However, the septal part of the annulus significantly decreased its maximal length (38.6 ± 8.1 to 37.9 ± 8.2 mm, P = 0.03). Annular contraction was not altered. The tricuspid annulus had a complex 3D saddle-shaped geometry that was unaffected during experimental conditions. In healthy sheep hearts, left ventricular unloading increased septal-free wall RV diameter and reduced the length of the septal annulus, without altering the motion or geometry of the tricuspid annulus. Acute left ventricular unloading alone in healthy sheep was not sufficient to significantly perturb tricuspid annular dynamics and result in tricuspid insufficiency. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

PLASMA DEVICE

DOEpatents

Gow, J.D.; Wilcox, J.M.

1961-12-26

A device is designed for producing and confining highenergy plasma from which neutrons are generated in copious quantities. A rotating sheath of electrons is established in a radial electric field and axial magnetic field produced within the device. The electron sheath serves as a strong ionizing medium to gas introdueed thereto and also functions as an extremely effective heating mechanism to the resulting plasma. In addition, improved confinement of the plasma is obtained by ring magnetic mirror fields produced at the ends of the device. Such ring mirror fields are defined by the magnetic field lines at the ends of the device diverging radially outward from the axis of the device and thereafter converging at spatial annular surfaces disposed concentrically thereabout. (AFC)

Enclosed ground-flare incinerator

DOEpatents

Wiseman, Thomas R.

2000-01-01

An improved ground flare is provided comprising a stack, two or more burner assemblies, and a servicing port so that some of the burner assemblies can be serviced while others remain in operation. The burner assemblies comprise a burner conduit and nozzles which are individually fitted to the stack's burner chamber and are each removably supported in the chamber. Each burner conduit is sealed to and sandwiched between a waste gas inlet port and a matching a closure port on the other side of the stack. The closure port can be opened for physically releasing the burner conduit and supplying sufficient axial movement room for extracting the conduit from the socket, thereby releasing the conduit for hand removal through a servicing port. Preferably, the lower end of the stack is formed of one or more axially displaced lower tubular shells which are concentrically spaced for forming annular inlets for admitting combustion air. An upper tubular exhaust stack, similarly formed, admits additional combustion air for increasing the efficiency of combustion, increasing the flow of exhausted for improved atmospheric dispersion and for cooling the upper stack.

Immediate and mid-term clinical course after percutaneous closure of paravalvular leakage.

PubMed

Sánchez-Recalde, Angel; Moreno, Raúl; Galeote, Guillermo; Jimenez-Valero, Santiago; Calvo, Luis; Sevillano, Joel Hernández; Arroyo-Ucar, Eduardo; López, Teresa; Mesa, José M; López-Sendón, José L

2014-08-01

Percutaneous closure of paravalvular leakage is an alternative to surgery in high-risk patients, but its use has been limited by a lack of specific devices. More appropriate devices-like the Amplatzer Vascular Plug III-have recently been developed, but information about their efficacy and safety is still scarce. The objective of the present study was to assess the mid-term results of paravalvular leakage closure with this device. We analyzed the clinical and echocardiographic course both in-hospital and mid-term (13 [9] months) in a series of 20 consecutive patients (age, 68 years; logistic EuroSCORE, 29) with paravalvular leakage and attempted percutaneous closure. Closure was attempted for 23 leaks (17 mitral and 6 aortic) during 22 procedures in 20 patients. Implantation was successful in 87% of the leaks and the procedure was successful in 83%-with success being defined as a reduction in regurgitation of ≥ 1 degree. Survival at 1 year was 64.7% and survival free of the composite event of death/surgery was 58.8%. The degree of residual regurgitation was not associated with mortality but was associated with functional status. Survivors showed significant improvement in functional class. Percutaneous closure of leakage with the Amplatzer Vascular Plug III is safe and efficient in the mid-term. However, mortality among high-risk patients is high independently of the degree of residual regurgitation, indicating that these procedures are performed when heart disease has reached an advanced stage. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Fenestrated Transcatheter ASD Closure in Adults with Diastolic Dysfunction and/or Pulmonary Hypertension: Case Series and Review of the Literature.

PubMed

Abdelkarim, Ayman; Levi, Daniel S; Tran, Bao; Ghobrial, Joanna; Aboulhosn, Jamil

2016-12-01

This study aims to evaluate the safety and efficacy of transcatheter fenestrated ASD closure and to summarize the literature regarding the published techniques and outcomes of transcatheter partial ASD closure. Patients with left ventricular diastolic dysfunction (LVDD) or right ventricular (RV) dysfunction and/or pulmonary hypertension (PHT) may suffer untoward consequences of complete closure of an ostium secundum atrial septal defect (ASD). Therefore, for patients that fall under these categories we suggest partial occlusion of the defect, which may be better tolerated than complete defect closure. After obtaining IRB approval, a search for patients that have undergone percutaneous ASD closure was performed in the Ahmanson/UCLA Adult Congenital Heart Disease Center database to identify which patients received a fenestrated ASD closure device. Eight consecutive patients ranging between 22 and 83 years of age (mean 48 years) with PHT and/or LVDD or RV dysfunction who underwent fenestrated transcatheter ASD closure at UCLA were identified. None of the subjects experienced complications related to the procedure. Postprocedure clinical evaluation showed improvement in symptoms and exercise capacity. Available follow-up transthoracic echocardiography data (mean 4 months, range 0-20 months) demonstrated patent fenestrations in four of eight patients. None of the patients had thromboembolic or infectious complications and there were no device migrations, erosions or embolizations. Partial ASD occlusion in patients with diastolic dysfunction or RV dysfunction and/or PHT is safe and may be better tolerated than complete ASD closure in selected patients. © 2016 Wiley Periodicals, Inc.

Microfluidic step-emulsification in a cylindrical geometry

NASA Astrophysics Data System (ADS)

Chakraborty, Indrajit; Leshansky, Alexander M.

2016-11-01

The model microfluidic device for high-throughput droplet generation in a confined cylindrical geometry is investigated numerically. The device comprises of core-annular pressure-driven flow of two immiscible viscous liquids through a cylindrical capillary connected co-axially to a tube of a larger diameter through a sudden expansion, mimicking the microfluidic step-emulsifier (1). To study this problem, the numerical simulations of axisymmetric Navier-Stokes equations have been carried out using an interface capturing procedure based on coupled level set and volume-of-fluid (CLSVOF) methods. The accuracy of the numerical method was favorably tested vs. the predictions of the linear stability analysis of core-annular two-phase flow in a cylindrical capillary. Three distinct flow regimes can be identified: the dripping (D) instability near the entrance to the capillary, the step- (S) and the balloon- (B) emulsification at the step-like expansion. Based on the simulation results we present the phase diagram quantifying transitions between various regimes in plane of the capillary number and the flow-rate ratio. MICROFLUSA EU H2020 project.

Formation of annular plasma downstream by magnetic aperture in the helicon experimental device

NASA Astrophysics Data System (ADS)

Ghosh, Soumen; Yadav, S.; Barada, K. K.; Chattopadhyay, P. K.; Ghosh, J.; Pal, R.; Bora, D.

2017-02-01

In the Helicon eXperimental (HeX) device, the geometric aperture is fixed, but the position of the magnetic aperture can be varied. Working with Argon gas in the pressure range of 1 - 10 × 10 - 4 mbar, an annular plasma (density ˜ 10 16 m - 3 ) is formed downstream, always in front of the magnetic aperture. This occurs irrespective of the relative position of the geometric aperture or the presence of a radial electric field. This is in contrary to the earlier proposition made by others that a radial electric field is necessary to produce a hollow plasma profile. Instead, the ionization of neutrals in the radially outer region by the tail electrons, rotating fast due to gradient-B drift in the azimuthal direction, seems to account for the observed off-axis density peaking in the present experiment. This also explains the variation of the plasma annulus diameter seen here by changing the input radio frequency power ( 100 - 800 W ) .

Enhancement of magneto-optical Faraday effects and extraordinary optical transmission in a tri-layer structure with rectangular annular arrays.

PubMed

Lei, Chengxin; Chen, Leyi; Tang, Zhixiong; Li, Daoyong; Cheng, Zhenzhi; Tang, Shaolong; Du, Youwei

2016-02-15

The properties of optics and magneto-optical Faraday effects in a metal-dielectric tri-layer structure with subwavelength rectangular annular arrays are investigated. It is noteworthy that we obtained the strongly enhanced Faraday rotation of the desired sign along with high transmittance by optimizing the parameters of the nanostructure in the visible spectral ranges. In this system, we obtained two extraordinary optical transmission (EOT) resonant peaks with enhanced Faraday rotations, whose signs are opposite, which may provide the possibility of designing multi-channel magneto-optical devices. Study results show that the maximum of the figure of merit (FOM) of the structure can be obtained between two EOT resonant peaks accompanied by an enhanced Faraday rotation. The positions of the maximum value of the FOM and resonant peaks of transmission along with a large Faraday rotation can be tailored by simply adjusting the geometric parameters of our models. These research findings are of great importance for future applications of magneto-optical devices.

A Planar Hall Thruster for Investigating Electron Mobility in ExB Devices (Preprint)

DTIC Science & Technology

2007-08-24

Hall thruster that emits and collects the Hall current across a planar discharge channel is described. The planar Hall thruster (PHT) is being investigated for use as a test bed to study electron mobility in ExB devices. The planar geometry attempts to de-couple the complex electron motion found in annular thrusters by using simplified geometry. During this initial test, the PHT was operated at discharge voltages between 50-150 V to verify operability and stability of the device. Hall current was emitted by hollow cathode electron sources and

Stratifying photo plots into volume classes...by crown closure comparator

Treesearch

Robert C. Aldrich

1967-01-01

As an aid to aerial photo interpretation, a Crown Closure Comparator has been developed. Printed as a positive film transparency, this device shows tree crowns as open dots on a black background. The Comparator is used to stratify I-acre plots into broad volume classes on single aerial photos using 4 crown-diameter and 9 crown-closure classes. It can also be used for...

Multigrid calculation of three-dimensional viscous cascade flows

NASA Technical Reports Server (NTRS)

Arnone, A.; Liou, M.-S.; Povinelli, L. A.

1991-01-01

A 3-D code for viscous cascade flow prediction was developed. The space discretization uses a cell-centered scheme with eigenvalue scaling to weigh the artificial dissipation terms. Computational efficiency of a four stage Runge-Kutta scheme is enhanced by using variable coefficients, implicit residual smoothing, and a full multigrid method. The Baldwin-Lomax eddy viscosity model is used for turbulence closure. A zonal, nonperiodic grid is used to minimize mesh distortion in and downstream of the throat region. Applications are presented for an annular vane with and without end wall contouring, and for a large scale linear cascade. The calculation is validated by comparing with experiments and by studying grid dependency.

Multigrid calculation of three-dimensional viscous cascade flows

NASA Technical Reports Server (NTRS)

Arnone, A.; Liou, M.-S.; Povinelli, L. A.

1991-01-01

A three-dimensional code for viscous cascade flow prediction has been developed. The space discretization uses a cell-centered scheme with eigenvalue scaling to weigh the artificial dissipation terms. Computational efficiency of a four-stage Runge-Kutta scheme is enhanced by using variable coefficients, implicit residual smoothing, and a full-multigrid method. The Baldwin-Lomax eddy-viscosity model is used for turbulence closure. A zonal, nonperiodic grid is used to minimize mesh distortion in and downstream of the throat region. Applications are presented for an annular vane with and without end wall contouring, and for a large-scale linear cascade. The calculation is validated by comparing with experiments and by studying grid dependency.

[Feasibility of device closure for multiple atrial septal defects using 3D printing and ultrasound-guided intervention technique].

PubMed

Qiu, X; Lü, B; Xu, N; Yan, C W; Ouyang, W B; Liu, Y; Zhang, F W; Yue, Z Q; Pang, K J; Pan, X B

2017-04-25

Objective: To investigate the feasibility of trans-catheter closure of multiple atrial septal defects (ASD) monitored by trans-thoracic echocardiography (TTE) under the guidance of 3D printing heart model. Methods: Between April and August 2016, a total of 21 patients (8 male and 13 female) with multiple ASD in Fuwai Hospital of Chinese Academy of Medical Sciences underwent CT scan and 3-dimensional echocardiography for heart disease model produced by 3D printing technique. The best occlusion program was determined through the simulation test on the model. Percutaneous device closure of multiple ASD was performed follow the predetermined program guided by TTE. Clinical follow-up including electrocardiogram and TTE was arranged at 1 month after the procedure. Results: The trans-catheter procedure was successful in all 21 patients using a single atrial septal occluder. Mild residual shunt was found in 5 patient in the immediate postoperative period, 3 of them were disappeared during postoperative follow-up. There was no death, vascular damage, arrhythmia, device migration, thromboembolism, valvular dysfunction during the follow-up period. Conclusion: The use of 3D printing heart model provides a useful reference for transcatheter device closure of multiple ASD achieving through ultrasound-guided intervention technique, which appears to be safe and feasible with good outcomes of short-term follow-up.

[Outcome of transcatheter closure of perimembranous ventricular septal defect with modified double-disk occluder device].

PubMed

Liu, Jing; You, Xiao-hua; Zhao, Xian-xian; Hu, Jian-qiang; Cao, Jiang; Xu, Rong-liang; Wu, Hong; Chen, Shao-ping; Zhang, Jian-liang; Zheng, Xing; Qin, Yong-wen

2010-04-01

To evaluate the efficacy and adverse effects of transcatheter closure of perimembranous ventricular septal defect (pmVSD) with modified double-disk occluder device (MDVO). Clinical data including clinical examination, electrocardiography daily after the procedure for a week, chest-X-rays and TTE before discharge and at 3-5 days after the procedure were analyzed from 604 patients underwent percutaneous closure of a pmVSD with MDVO at our department between December 2001 and December 2008. Procedure was successful in 576 out of 604 patients (95.4%) and 583 VSD occluders were placed. Endocarditis, thromboembolism, or deaths were not observed after procedure. Conduction block occurred in 81 patients (56 RBBB, 14 LBBB) and transient nonparoxysmal ventricular tachycardia in 31 patients after the procedure. Complete heart block occurred in 11 patients, 9 of them recovered in 3 weeks, permanent pacemaker was implanted in 2 patients (one had transient III degrees AVB before the procedure, the other underwent simultaneous closure of ventricular septal defect and atrial septal defect). Trivial/small residual shunts were found in 69 patients (12.0%). The residual shunts disappeared in 31 patients and remained unchanged in 38 patients (6.6%) 7 days after procedures. Aortic regurgitation developed in 5 patients (2 trivial/small, 3 small/moderate), and tricuspid regurgitation was present in 35 patients (32 trivial/small, 3 moderate). Five patients developed haemolysis (device retrieved via catheter in 1 patient due to persistent haemolysis, the other 4 patients recovered 3-14 days post procedure). Pseudoaneurysm of femoral artery occurred in 1 patient, and disappeared by pressure dressing. Device was successfully replaced in 2 patients with either device embolization (n = 1) or device misplacement (n = 1) after device retrieval by catheter. It is safe and effective to close congenital perimembranous ventricular septal defect with domestic-made occluder device.

Transcranial Doppler quantification of residual shunt after percutaneous patent foramen ovale closure: correlation of device efficacy with intracardiac anatomic measures.

PubMed

Sorensen, Sherman G; Spruance, Spotswood L; Smout, Randall; Horn, Susan

2012-06-01

Percutaneous, mechanical closure of defects of the atrial septum fails to completely resolve shunting in up to 20% of cases. Little is known about the factors associated with device failure. We measured the left atrial opening (X), right atrial opening (Z), tunnel length (Y), septum secundum, device-septum primum separation, and tunnel compressibility of the patent foramen ovale (PFO) in 301 patients with cryptogenic neurological events, PFO anatomy, and severe Valsalva shunting (Spencer Grade 5-5+). All patients then underwent percutaneous closure with the GORE®HELEX Septal Occluder device and were evaluated at 3 months for residual shunt by transcranial Doppler (TCD). Severe residual Valsalva shunt (TCD Grade 5-5+) was found at 3 months in 21 of 301 (7%) patients. X, Y, and Z were associated with failure with a high degree of statistical significance, whereas the width of the septum secundum, device-septum primum separation, and tunnel compressibility were not. An unanticipated finding was that 14 of 35 (40%) patients sized with a large balloon failed compared with 9 of 280 (3%) sized with a small balloon (P < 0.0001). In the multivariate logistic regression model, X (P = < 0.0001) and balloon size (P < 0.0001) were both strong predictors of failure. In an intracardiac echocardiography-defined PFO population, characterized by severe baseline Valsalva shunt and a high incidence of persistent (rest) shunting, association of six intracardiac measurements to closure device failure by multivariate logistic regression showed that the width of the left atrial opening was a strong predictor of residual shunting. An unanticipated finding was that use of a large sizing balloon was also strongly associated with failure. ©2012, Wiley Periodicals, Inc.

Comparison of effectiveness and cost of patent ductus arteriosus device occlusion versus surgical ligation of patent ductus arteriosus.

PubMed

Zulqarnain, Arif; Younas, Muhammad; Waqar, Tariq; Beg, Ahsan; Asma, Touseef; Baig, Mirza Ahmad Raza

2016-01-01

Comparison of effectiveness and cost of transcatheter occlusion of patent ductus arteriosus (PDA) with surgical ligation of PDA. This retrospective comparative study was conducted in the pediatric cardiology department of Ch. Pervaiz Elahi Institute of Cardiology Multan, Pakistan. Data of 250 patients who underwent patent ductus arteriosus (PDA) closure either surgical or trans-catheter closure using SHSMA Occluder having weight >5 kg from April 2012 to October 2015 were included in this study. SPSS version 20 was used for data analysis. Quantitative variables were compared using independent sample t-test. Chi-square test and fishers exact was used for qualitative variables. P-value <0.05 was considered statistically significant. There were one hundred and twenty (120) patients who underwent transcatheter occlusion of PDA using SHSMA occluder (PDA Device Group) and one hundred and thirty (130) patients who underwent surgical ligation of PDA (Surgical Group). Incidence of residual shunting was two (1.5%) in surgical group and 0 (0.0%) in PDA Device group for one month follow up period. There were 4 (3.1%) major complications in surgical group. The rate of blood transfusions were high in surgical group (p-value 0.04). Hospital stay time was significantly less in PDA Device group (P-value <0.001). Total procedural cost was 110695+1054 Pakistani rupees in PDA Device group and 92414+3512 in surgical group (p-value <0.001). The cost of PDA device closure was 16.52% higher than the surgical ligation of PDA. There was no operative mortality. The transcatheter closure of PDA is an effective and less invasive method as compared to the surgical ligation. There is a lower rate of complications and the cost is not much high as compared to surgical PDA ligation.

Tunable high-q superconducting notch filter

DOEpatents

Pang, C.S.; Falco, C.M.; Kampwirth, R.T.; Schuller, I.K.

1979-11-29

A superconducting notch filter is made of three substrates disposed in a cryogenic environment. A superconducting material is disposed on one substrate in a pattern of a circle and an annular ring connected together. The second substrate has a corresponding pattern to form a parallel plate capacitor and the second substrate has the circle and annular ring connected by a superconducting spiral that forms an inductor. The third substrate has a superconducting spiral that is placed parallel to the first superconducting spiral to form a transformer. Relative motion of the first substrate with respect to the second is effected from outside the cryogenic environment to vary the capacitance and hence the frequency of the resonant circuit formed by the superconducting devices.

77 FR 55496 - Notice of Temporary Closure of Public Lands in Eastern Lassen County, California, and Western...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-10

... protection and State, local and Federal officials involved with enforcement. This closure is necessary to.... Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay...

Cost effectiveness of left atrial appendage closure with the Watchman device for atrial fibrillation patients with absolute contraindications to warfarin

PubMed Central

Reddy, Vivek Y.; Akehurst, Ronald L.; Armstrong, Shannon O.; Amorosi, Stacey L.; Brereton, Nic; Hertz, Deanna S.; Holmes, David R.

2016-01-01

Abstract Aims Atrial fibrillation (AF) patients with contraindications to oral anticoagulation have had few options for stroke prevention. Recently, a novel oral anticoagulant, apixaban, and percutaneous left atrial appendage closure (LAAC) have emerged as safe and effective therapies for stroke risk reduction in these patients. This analysis assessed the cost effectiveness of LAAC with the Watchman device relative to apixaban and aspirin therapy in patients with non-valvular AF and contraindications to warfarin therapy. Methods and results A cost-effectiveness model was constructed using data from three studies on stroke prevention in patients with contraindications: the ASAP study evaluating the Watchman device, the ACTIVE A trial of aspirin and clopidogrel, and the AVERROES trial evaluating apixaban. The cost-effectiveness analysis was conducted from a German healthcare payer perspective over a 20-year time horizon. Left atrial appendage closure yielded more quality-adjusted life years (QALYs) than aspirin and apixaban by 2 and 4 years, respectively. At 5 years, LAAC was cost effective compared with aspirin with an incremental cost-effectiveness ratio (ICER) of €16 971. Left atrial appendage closure was cost effective compared with apixaban at 7 years with an ICER of €9040. Left atrial appendage closure was cost saving and more effective than aspirin and apixaban at 8 years and remained so throughout the 20-year time horizon. Conclusions This analysis demonstrates that LAAC with the Watchman device is a cost-effective and cost-saving solution for stroke risk reduction in patients with non-valvular AF who are at risk for stroke but have contraindications to warfarin. PMID:26838691

Atrial septal defect closure with the new Cardia Ultrasept II™ device with interposed Goretex patch: Mexican experience - has the perforation of Ivalon's membrane been solved?

PubMed

Mijangos-Vázquez, Roberto; García-Montes, Antonio J; Soto-López, Elena M; Guarner-Lans, Verónica; Zabal, Carlos

2018-05-01

The objective of this study was to demonstrate the safety and feasibility of using the new Cardia Ultrasept II™ device with interposed Goretex patch referring to the perforation of polyvinyl alcohol membrane. Great advances have been made in the development of devices for closure of atrial septal defect. The Cardia Ultrasept II™ with interposed Goretex patch is the modified last generation of Cardia devices, having the advantage of a super-low profile within the atria and an integral locking delivery-retrieval mechanism that ensures safe deployment. In addition, with the interposition of the Goretex, it has been possible to abolish perforation of Ivalon's membrane as a complication.Methods and resultsPatients with ostium secundum atrial septal defect with surrounding rims with a minimum length of 5 mm and who underwent atrial septal defect closure with the new Ultrasept II™ with Goretex patch were included from two paediatric cardiac centres. Primary end point was to determine perforation of the Goretex membrane at follow-up; secondary end point included right ventricular diastolic diameter. In total, 30 patients underwent atrial septal defect closure at a median age of 6 (1-29) years. At follow-up for 6 (range, 1-15) months, freedom from perforations was 100%. A continuous decrease in right ventricular diastolic diameter was found with an initial median of 30 (25-49) mm and after catheterisation of 27.5 (18-33) mm, p=0.01, and Z-score of 2.6 (1.7-3.6) versus 1.9 (1-2.9) after procedure, p=0.01. The new modified generation of the Ultrasept II™ device with interposed Goretex patch is a good alternative to achieve atrial septal defect closure safely and feasibly with no membrane perforation at follow-up.

MAGNETIC END CLOSURES FOR PLASMA CONFINING AND HEATING DEVICES

DOEpatents

Post, R.F.

1963-08-20

More effective magnetic closure field regions for various open-ended containment magnetic fields used in fusion reactor devices are provided by several spaced, coaxially-aligned solenoids utilized to produce a series of nodal field regions of uniform or, preferably, of incrementally increasing intensity separated by lower intensity regions outwardly from the ends of said containment zone. Plasma sources may also be provided to inject plasma into said lower intensity areas to increase plasma density therein. Plasma may then be transported, by plasma diffusion mechanisms provided by the nodal fields, into the containment field. With correlated plasma densities and nodal field spacings approximating the mean free partl cle collision path length in the zones between the nodal fields, optimum closure effectiveness is obtained. (AEC)

Use of an Amplatzer Device for Endoscopic Closure of a Large Bronchopleural Fistula following Lobectomy for a Stage I Squamous Cell Carcinoma.

PubMed

Ottevaere, A; Slabbynck, H; Vermeersch, P; Rogiers, P; Galdermans, D; De Droogh, E; Bedert, L

2013-01-01

Bronchopleural fistulas can occur as a rare but severe complication after pulmonary resection. Established guidelines for the proper treatment of patients with bronchopleural fistulas do not exist. Apart from attempts to close the fistula, emphasis is placed on preventive measures, early treatment with antibiotics, drainage of the empyema and aggressive nutritional and rehabilitative support. For inoperable patients, endoscopic procedures are the only therapeutic option. Unfortunately, large (>8 mm) or central bronchopleural fistulas are usually not suitable for such endoscopic management. Recently, some groups have published a few case reports about a novel technique for the endobronchial closure of bronchopleural fistulas, using an Amplatzer device, originally designed for transcatheter closure of cardiac septal defects. We applied the same technique as a life-saving treatment in a ventilated patient who was considered inoperable due to a high oxygen need. The operation was successful. The patient could be weaned from ventilation and was eventually discharged from the hospital to a rehabilitation facility several weeks after the insertion of the device. Until now, endoscopic techniques have only been useful for the treatment of small, peripheral, bronchopleural fistulas and even then only as a bridge to surgery in high-risk surgical patients. In this case report, we demonstrate that the use of an Amplatzer device can expand the importance of endoscopic techniques in the treatment of bronchopleural fistulas. An Amplatzer device, for endobronchial closure, can indeed be administered for large and central bronchopleural fistulas. Moreover, it can be considered as a definite alternative to surgery in inoperable patients.

Management of a large atrial septal occluder embolized to the left ventricular outflow tract without the use of cardiac surgery.

PubMed

Loh, Joshua P; Satler, Lowell F; Slack, Michael C

2014-09-01

Transcatheter closure of secundum-type atrial septal defects (ASDs) using the AMPLATZER™ Septal Occluder (ASO) has been in use for more than a decade since its US Food and Drug Administration approval in 2001. Device embolization remains an uncommon complication, which can sometimes occur after the initial deployment. Previous reports of ASO devices embolized to the left ventricle have primarily been managed by open-heart surgical retrieval. We present a case of an ASO device embolized to the left ventricular outflow tract (LVOT) 18 hr after initial implantation, which was successfully retrieved percutaneously, followed by successful closure of the ASD using a larger device. © 2014 Wiley Periodicals, Inc.

Device for testing closure disks at high rates of change of pressure

DOEpatents

Merten, Jr., Charles W.

1993-11-09

A device for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A means is also disclosed for transmitting a tensile load from a piston to a hollow notched plug and for sealing the means for transmitting load within a hole in a piston.

Intracardiac echocardiography: use during transcatheter device closure of a patent ductus arteriosus in a dog.

PubMed

Chetboul, V; Damoiseaux, C; Behr, L; Morlet, A; Moise, N S; Gouni, V; Lavennes, M; Pouchelon, J-L; Laborde, F; Borenstein, N

2017-06-01

Intracardiac echocardiography (ICE) is used in humans for percutaneous interventional procedures, such as transcatheter device closures. Intracardiac echocardiography provides high-resolution imaging of cardiac structures with two-dimensional, M-mode, Doppler, and also three-dimensional modalities. The present report describes application of ICE during transcatheter occlusion of patent ductus arteriosus using a canine ductal occluder in a dog for which transesophageal echocardiography could not provide an optimal acoustic window. Copyright © 2017 Elsevier B.V. All rights reserved.

49 CFR 173.226 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone A.

Code of Federal Regulations, 2011 CFR

2011-10-01

...; (3) Have screw-type closures that are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in...

49 CFR 173.226 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone A.

Code of Federal Regulations, 2012 CFR

2012-10-01

...; (3) Have screw-type closures that are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in...

49 CFR 173.226 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone A.

Code of Federal Regulations, 2013 CFR

2013-10-01

...; (3) Have screw-type closures that are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in...

49 CFR 173.226 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone A.

Code of Federal Regulations, 2010 CFR

2010-10-01

...; (3) Have screw-type closures that are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in...

49 CFR 173.226 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone A.

Code of Federal Regulations, 2014 CFR

2014-10-01

...; (3) Have screw-type closures that are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in...

Torque sensor having a spoked sensor element support structure

NASA Technical Reports Server (NTRS)

Lurie, Boris J. (Inventor); Schier, J. Alan (Inventor)

1990-01-01

Piezoelectric sensor devices are attached across pairs of circularly arranged spokes arrayed on the periphery of an annular ring. The sensor devices each include a preloaded steel ball mounting arrangement for mounting a piezoelectric sensor element. A first circular interface plate on one side of the sensor structure attaches to alternate one of the spokes, and a circular interface plate on the opposite side of the same diameter as the first interface plate attaches to the remaining spokes.

Transcatheter closure, mini-invasive closure and open-heart surgical repair for treatment of perimembranous ventricular septal defects in children: a protocol for a network meta-analysis.

PubMed

You, Tao; Yi, Kang; Ding, Zhao-Hong; Hou, Xiao-Dong; Liu, Xing-Guang; Wang, Xin-Kuan; Ge, Long; Tian, Jin-Hui

2017-06-21

Both transcatheter device closure and surgical repair are effective treatments with excellent midterm outcomes for perimembranous ventricular septal defects (pmVSDs) in children. The mini-invasive periventricular device occlusion technique has become prevalent in research and application, but evidence is limited for the assessment of transcatheter closure, mini-invasive closure and open-heart surgical repair. This study comprehensively compares the efficacy, safety and costs of transcatheter closure, mini-invasive closure and open-heart surgical repair for treatment of pmVSDs in children using Bayesian network meta-analysis. A systematic search will be performed using Chinese Biomedical Literature Database, China National Knowledge Infrastructure, PubMed, EMBASE.com and the Cochrane Central Register of Controlled Trials to include random controlled trials, prospective or retrospective cohort studies comparing the efficacy, safety and costs of transcatheter closure, mini-invasive closure and open-heart surgical repair. The risk of bias for the included prospective or retrospective cohort studies will be evaluated according to the risk of bias in non-randomised studies of interventions (ROBINS-I). For random controlled trials, we will use risk of bias tool from Cochrane Handbook version 5.1.0. A Bayesian network meta-analysis will be conducted using R-3.3.2 software. Ethical approval and patient consent are not required since this study is a network meta-analysis based on published trials. The results of this network meta-analysis will be submitted to a peer-reviewed journal for publication. CRD42016053352. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Left ventricular remodeling and change of systolic function after closure of patent ductus arteriosus in adults: device and surgical closure.

PubMed

Jeong, Young-Hoon; Yun, Tae-Jin; Song, Jong-Min; Park, Jung-Jun; Seo, Dong-Man; Koh, Jae-Kon; Lee, Se-Whan; Kim, Mi-Jeong; Kang, Duk-Hyun; Song, Jae-Kwan

2007-09-01

Left ventricular (LV) remodeling and predictors of LV systolic function late after closure of patent ductus arteriosus (PDA) in adults remain to be clearly demonstrated. In 45 patients with PDA, including 28 patients who received successful occlusion using the Amplatzer device (AD group) (AGA, Golden Valley, MN) and 17 patients who received surgical closure (OP group), echocardiography studies were performed before closure and 1 day (AD group) or within 7 days (OP group) after closure, and then were repeated at > or = 6 months (17 +/- 13 months). In both groups, LV ejection fraction (EF) and end-diastolic volume index were significantly decreased immediately after closure, whereas end-systolic volume index did not change. During the long-term follow-up period, end-systolic as well as end-diastolic volume indices decreased significantly in both groups and LV EF recovered compared to the immediate postclosure state. However, LV EF remained low compared to the preclosure state. Five patients (11.1%) including 3 patients in the AD group and 2 patients in the OP group showed persistent late LV systolic dysfunction (EF <50%). In stepwise, multiple logistic regression analysis, preclosure EF was the only independent predictor of late normal postclosure EF (odds ratio, 1.230; 95% CI, 1.054-1.434; P = .008). Receiver operating characteristic curve analysis showed that preclosure EF > or = 62% had a sensitivity of 72% and a specificity of 83% for predicting late normal LV EF after closure. Left ventricular EF remains low late after PDA closure compared with preclosure state in adults. Preclosure LV EF is the best index to predict late postclosure LV EF.

Percutaneous patent foramen ovale closure: the Paradoxical Cerebral Embolism Prevention Registry.

PubMed

Paiva, Luís; Dinis, Paulo; Providência, Rui; Costa, Marco; Margalho, Susana; Goncalves, Lino

2015-03-01

The natural history and therapeutic interventions for secondary prevention after a cerebrovascular event in patients with patent foramen ovale (PFO) are not yet established. This study aims to assess the safety and efficacy of percutaneous PFO closure in a population of patients with ischemic cerebrovascular disease of unknown etiology. This prospective observational study included patients with a history of cryptogenic transient ischemic attack (TIA) or stroke who underwent percutaneous PFO closure. The effectiveness of the device for the secondary prevention of TIA or stroke was assessed by comparing observed events in the sample with expected events for this clinical setting. The sample included 193 cases of percutaneous PFO closure (age 46.4 ± 13.1 years, 62.2% female) with a mean follow-up of 4.3 ± 2.2 years, corresponding to a total exposure to ischemic events of 542 patient-years. The high-risk characteristics of the PFO were assessed prior to device implantation. There were seven primary endpoint events during follow-up (1.3 per 100 patient-years), corresponding to a relative risk reduction of 68.2% in recurrent TIA or stroke compared to medical therapy alone. The procedure was associated with a low rate of device- or intervention-related complications (1.5%). In this long-term registry, percutaneous PFO closure was shown to be a safe and effective therapy for the secondary prevention of cryptogenic stroke or TIA. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Bacterial Composition of Biofilms Collected From Two Service Areas in a Metropolitan Drinking Water Distribution System

EPA Science Inventory

The development and succession of bacteria were examined by 16S rRNA gene clone libraries generated from various biofilms within a metropolitan water distribution system. Biofilms were obtained from off-line devices using polycarbonate coupons from annular reactors incubated for ...

Usefulness of Tricuspid Annular Diameter to Predict Late Right Sided Heart Failure in Patients With Left Ventricular Assist Device.

PubMed

Nakanishi, Koki; Homma, Shunichi; Han, Jiho; Takayama, Hiroo; Colombo, Paolo C; Yuzefpolskaya, Melana; Garan, Arthur R; Farr, Maryjane A; Kurlansky, Paul; Di Tullio, Marco R; Naka, Yoshifumi; Takeda, Koji

2018-07-01

Although late-onset right-sided heart failure is recognized as a clinical problem in the treatment of patients with left ventricular assist devices (LVADs), the mechanism and predictors are unknown. Tricuspid valve (TV) deformation leads to the restriction of the leaflet motion and decreased coaptation, resulting in a functional tricuspid regurgitation that may act as a surrogate marker of late right-sided heart failure. This study aimed to investigate the association of preoperative TV deformation (annulus dilatation and leaflet tethering) with late right-sided heart failure development after continuous-flow LVAD implantation. The study cohort consisted of 274 patients who underwent 2-dimensional echocardiography before LVAD implantation. TV annulus diameter and tethering distance were measured in an apical 4-chamber view. Late right-sided heart failure was defined as right-sided heart failure requiring readmission and medical and/or surgical treatment after initial LVAD implantation. During a mean follow-up of 25.1 ± 19.0 months after LVAD implantation, late right-sided heart failure occurred in 33 patients (12.0%). Multivariate Cox proportional hazard analysis demonstrated that TV annulus diameter (hazard ratio 1.221 per 1 mm, p <0.001) was significantly associated with late right-sided heart failure development, whereas leaflet tethering distance was not. The best cut-off value of the TV annular diameter was 41 mm (area under the curve 0.787). Kaplan-Meier analysis showed that patients with dilated TV annulus (TV annular diameter ≥41 mm) exhibited a significantly higher late right-sided heart failure occurrence than those without TV annular enlargement (log-rank p <0.001). In conclusion, preoperative TV annulus diameter, but not leaflet tethering distance, predicted the occurrence of late right-sided heart failure after LVAD implantation. Copyright © 2018 Elsevier Inc. All rights reserved.

Closure of patent foramen ovale: when and how?

PubMed

Lisignoli, Veronica; Lanzone, Alberto M; Zavalloni, Dennis; Pagnotta, Paolo; Presbitero, Patrizia

2007-10-01

Percutaneous closure of a patent foramen ovale (PFO) was performed in 98 consecutive patients (mean age 52.5 +/- 13 years, 61 women). Indications included recurrent transient ischaemic attack (47%), cryptogenic stroke (34%), peripheral embolism (11%), disabling migraine with aura (4%), professional scuba diving (1 pt) and severe platypnea-orthodeoxia syndrome (1 pt). Each PFO was characterized by transesophageal echocardiography (TEE) according to anatomy, degree of shunt (1-mild, 2-moderate, 3-severe), right atrial anatomical features relevant for PFO closure (such as presence of an Eustachian valve, Chiari network, lipomatosis or absence of septum secundum) with a new classification scheme. According to this classification successful device delivery was obtained in 100% of pts. Major complications included heparin-induced thrombocytopenia in 1 pt and device dislodgment in 1 pt; minor complications were mostly related to the catheter introduction site (2 pts) and mild immediate shunt (2 pts). In conclusion, percutaneous PFO closure based on strict anatomic criteria is a safe procedure with minimal periprocedural complications.

Pan-nitinol occluder and special delivery device for closure of patent ductus arteriosus: a canine-model feasibility study.

PubMed

Jiang, Hai-bin; Bai, Yuan; Zong, Gang-jun; Han, Lin; Li, Wei-ping; Lu, Yang; Qin, Yong-wen; Zhao, Xian-xian

2013-01-01

The aim of this study was to evaluate a new type of occluder for patent ductus arteriosus. Patent ductus arteriosus was established in a canine model by anastomosing a length of autologous jugular vein to the descending aorta and the left pulmonary artery in an end-to-side fashion. Transcatheter closure of each patent ductus arteriosus was performed on 10 dogs, which were then monitored for as long as 6 months with aortography, echocardiography, and histologic evaluation. Transcatheter closure with use of the novel pan-nitinol device was successful in all canine models. Postoperative echocardiography showed that the location and shape of the occluders were normal, without any residual shunting. Further histologic evaluation confirmed that the occluder surface was completely endothelialized 3 months after implantation. Transcatheter patent ductus arteriosus closure with the pan-nitinol occluder can be performed safely and successfully in a canine model and shows good biological compatibility and low mortality rates.

Transcatheter closure of left ventricle to right atrial communication using cera duct occluder.

PubMed

Ganesan, Gnanavelu; Paul, G Justin; Mahadevan, Vaikom S

Left ventricle-right atrial communication could be congenital (Gerbode defect) or acquired as a complication of surgery or infective endocarditis and leads to volume overloading of pulmonary circulation. Two types, direct and indirect types are known depending on the involvement of septal tricuspid leaflet. Transcatheter closure of this defect is feasible and appears an attractive alternative to surgical management. Various devices like Amplatzer duct occluder I, II, Muscular ventricular septal defect device etc. have been used to close this defect. We report two patients, a preteen boy with direct left ventricle-right atrial communication as post operative complication and an adult female with indirect communication who underwent transcatheter closure with Cera duct occluder (Lifetech Scientific (Shenzhen), China). Copyright © 2017. Published by Elsevier B.V.

Hemolysis induced by PMIVSD occluder.

PubMed

Rao, D Sheshagiri; Barik, Ramachandra; Siva Prasad, Akula

2016-09-01

Hemolysis related to occluder, prosthetic valve, and prosthetic ring used for mitral valve annuloplasty are not very unusual. However, hemolysis related to transcathetor closure of post-myocardial infarction ventricular septal defect (PMIVSD) is infrequent. A close follow-up for spontaneous resolution with or without blood transfusion has been reported in a few cases. Occasionally, surgical retrieval is unavoidable or lifelong blood transfusion is required if surgery cannot be done because of higher risk. In this illustration, we have showed a close follow-up of a case of hemolysis induced by atrial septal occluder used for VSD closure after myocardial infarction. Despite successful device closure of PMIVSD which is difficult, a close watch is needed for complications like residual leak, device embolization, and hemolysis. Copyright © 2016 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Amplatzer angled duct occluder for closure of patent ductus arteriosus larger than the aorta in an infant.

PubMed

Vijayalakshmi, I B; Chitra, N; Rajasri, R; Prabhudeva, A N

2005-01-01

Transcatheter closure of patent ductus arteriosus (PDA) by Amplatzer duct occluder is the treatment of choice. However, closure of very large ducts in infants with low weight is a challenge for the interventionalist because a large device may obstruct the aorta or left pulmonary artery. Difficulty is also encountered in advancing the device around the curve of the right ventricular outflow tract toward the pulmonary artery; this curve is tight, more or less at a right angle in infants, leading to kinking of the sheath, which increases fluoroscopic time. This is the first reported case of a very large PDA (8.7 mm), larger than the aorta (8.2 mm), successfully closed by an Amplatzer angled duct occluder in an infant weighing 5 kg.

46 CFR 151.15-10 - Cargo gauging devices.

Code of Federal Regulations, 2010 CFR

2010-10-01

... contains definitions and requirements for types of gauging devices specified in Table 151.05. (a) Open... the cargo and its vapors. Examples of this type are gauge hatch, ullage hole. (b) Restricted. A... closure device in that opening. When not in use, this type gauging device is closed to maintain the...

Evaluation of innovative devices to control traffic entering from low-volume access points within a land closure.

DOT National Transportation Integrated Search

2014-04-01

This report describes the methodology and results of analyses performed to identify and evaluate : alternative methods to control traffic entering a lane closure on a two-lane, two-way road from low-volume : access points. Researchers documented the ...

Digital controller design: Analysis of the annular suspension pointing system

NASA Technical Reports Server (NTRS)

Kuo, B. C.

1979-01-01

The Annular Suspension and Pointing System (ASPS) is a payload auxiliary pointing device of the Space Shuttle. The ASPS is comprised of two major subassemblies, a vernier and a coarse pointing subsystem. The experiment is attached to a mounting plate/rim combination which is suspended on magnetic bearing/actuators (MBA) strategically located about the rim. Fine pointing is achieved by gimballing the plate/rim within the MBA gaps. Control about the experiment line-of-sight is obtained through the use of a non-contacting rim drive and positioning torquer. All sensors used to close the servo loops on the vernier system are noncontacting elements. Therefore, the experiment is a free-flyer constrained only by the magnetic forces generated by the control loops.

APPARATUS FOR PRODUCING HIGH VELOCITY SHOCK WAVES IN GASES

DOEpatents

Scott, F.R.; Josephson, V.

1960-02-01

>A device for producing a high-energy ionized gas region comprises an evacuated tapered insulating vessel and a substantially hemispherical insulating cap hermetically affixed to the large end of the vessel, an annular electrode having a diameter equal to and supported in the interior wall of the vessel at the large end and having a conductive portion inside the vessel, a second electrode supported at the small end of the vessel, means connected to the vessel for introducing a selected gas therein, a source of high potential having two poles. means for connecting one pole of the high potential source to the annular electrode, and means for connecting the other pole of the potential source to the second electrode.

Improved ion detector

DOEpatents

Tullis, A.M.

1986-01-30

An improved ion detector device of the ionization detection device chamber type comprises an ionization chamber having a central electrode therein surrounded by a cylindrical electrode member within the chamber with a collar frictionally fitted around at least one of the electrodes. The collar has electrical contact means carried in an annular groove in an inner bore of the collar to contact the outer surface of the electrode to provide electrical contact between an external terminal and the electrode without the need to solder leads to the electrode.

Vapordynamic thermosyphon - heat transfer two-phase device for wide applications

NASA Astrophysics Data System (ADS)

Vasiliev, Leonard; Vasiliev, Leonid; Zhuravlyov, Alexander; Shapovalov, Aleksander; Rodin, Aleksei

2015-12-01

Vapordynamic thermosyphon (VDT) is an efficient heat transfer device. The two-phase flow generation and dynamic interaction between the liquid slugs and vapor bubbles in the annular minichannel of the VDT condenser are the main features of such thermosyphon, which allowed to increase its thermodynamic efficiency. VDT can transfer heat in horizontal position over a long distance. The condenser is nearly isothermal with the length of tens of meters. The VDT evaporators may have different forms. Some practical applications of VDT are considered.

Thromboembolism after WATCHMANTM in a clopidogrel non-responder: A case for concern?

PubMed

Venkataraman, Ganesh; Bliden, Kevin P; Tantry, Udaya S; Gurbel, Paul A

2017-11-11

Atrial fibrillation (AF) is associated with an increased risk of stroke and thromboembolism (TE). The WATCHMAN TM left atrial appendage (LAA) closure device is indicated to reduce the risk of TE from the LAA in patients with non-valvular AF. Here, we present a case of a patient with device-related thrombus who suffered a TE event two months after WATCHMAN TM LAA closure and two weeks after switching from aspirin plus warfarin to aspirin plus clopidogrel therapy. Laboratory investigation identified the patient to be hypercoagulable and to be a non-responder to clopidogrel therapy. We discuss the potential role of platelet function testing to prevent device-related thrombi. © 2017 Wiley Periodicals, Inc.

Transcatheter closure of patent foramen ovale for secondary prevention of ischemic stroke: Quantitative synthesis of pooled randomized trial data.

PubMed

Hakeem, Abdul; Cilingiroglu, Mehmet; Katramados, Angelos; Boudoulas, Konstantinos Dean; Iliescu, Cezar; Gundogdu, Betul; Marmagkiolis, Konstantinos

2018-01-14

To evaluate the safety and efficacy of percutaneous device closure of patent foramen ovale (PFO) for secondary prevention of ischemic stroke BACKGROUND: Stroke remains the leading cause of serious long-term disability in the United States. The effectiveness of a percutaneous PFO closure in the prevention of recurrent cryptogenic strokes has not been established. We performed a literature search using PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Google Scholar, and Internet-based sources from January 2003 to September 2017. Randomized controlled trails (RCTs) comparing percutaneous PFO closure to medical therapy alone. Five RCTs (CLOSURE I, PC Trial, REDUCE, RESPECT, and CLOSE) with 1,829 patients in the device group and 1,611 patients in the medical group met inclusion criteria. The cumulative incidence of recurrent stroke was 2.02% in the PFO closure arm and 4.4% in the medical therapy group (RR 0.42, 95%CI 0.20, 0.91; P = 0.03). There was no difference in the incidence of death [0.7% vs. 0.9%; RR 0.76 (95% CI 0.35, 1.64), P = 0.49] or adverse events during the follow-up period [24.6% vs. 23.7% (RR 1.03; 95% CI 0.91, 1.16), P = 0.65] between the closure and medical therapy groups. Incidence of atrial fibrillation was significantly higher in closure group compared to medical therapy [4% vs. 0.6% (RR 4.73; 95% CI 2.09, 10.70), P = 0.0002]. The comparative effectiveness of PFO closure (compared to medical therapy) was significantly more pronounced in those younger than 45 years, males, larger shunts and disc design platforms (P < 0.05). Based on the results of this analysis of randomized trial data, percutaneous PFO closure appears to be a safe and effective therapeutic option for the secondary prevention of ischemic stroke in patients with PFO and cryptogenic stroke. © 2018 Wiley Periodicals, Inc.

An experimental investigation of two large annular diffusers with swirling and distorted inflow

NASA Technical Reports Server (NTRS)

Eckert, W. T.; Johnston, J. P.; Simons, T. D.; Mort, K. W.; Page, V. R.

1980-01-01

Two annular diffusers downstream of a nacelle-mounted fan were tested for aerodynamic performance, measured in terms of two static pressure recovery parameters (one near the diffuser exit plane and one about three diameters downstream in the settling duct) in the presence of several inflow conditions. The two diffusers each had an inlet diameter of 1.84 m, an area ratio of 2.3, and an equivalent cone angle of 11.5, but were distinguished by centerbodies of different lengths. The dependence of diffuser performance on various combinations of swirling, radially distorted, and/or azimuthally distorted inflow was examined. Swirling flow and distortions in the axial velocity profile in the annulus upstream of the diffuser inlet were caused by the intrinsic flow patterns downstream of a fan in a duct and by artificial intensification of the distortions. Azimuthal distortions or defects were generated by the addition of four artificial devices (screens and fences). Pressure recovery data indicated beneficial effects of both radial distortion (for a limited range of distortion levels) and inflow swirl. Small amounts of azimuthal distortion created by the artificial devices produced only small effects on diffuser performance. A large artificial distortion device was required to produce enough azimuthal flow distortion to significantly degrade the diffuser static pressure recovery.

Patent Ductus Arteriosus closure in preterms less than 2kg: Surgery versus transcatheter.

PubMed

Pamukcu, Ozge; Tuncay, Aydin; Narin, Nazmi; Baykan, Ali; Korkmaz, Levent; Argun, Mustafa; Ozyurt, Abdullah; Sunkak, Suleyman; Uzum, Kazim

2018-01-01

As new devices come into the market, percutaneous techniques improve and interventionalists become more experienced; percutaneous closure gets more common in preterms. In this study we aimed to compare efficacy and safety of Patent Ductus Arteriosus closure surgically versus transcatheter method in preterms <2kg. Best of our knowledge this study is the first one that compares outcomes of surgery and percutaneous Patent Ductus Arteriosus closure in preterms. Between the dates July 1997 to October 2014 in our center Patent Ductus Arteriosus of 26 patients <2kg were closed percutaneously (Group A) and 31 less than 2kg operated (Group B). Weight of patients in percutaneous Patent Ductus Arteriosus closure group was significantly more than the surgery group. Mean gestational age of the patients in Group A was 30±1.8weeks, in group B was 28.6±3.5weeks. In group A; all cases were closed successfully except 4 cases: device embolization in 2, cardiac tamponade and iatrogenic aortic coarctation were seen. Pneumomediastinum and chylothorax were the major complications of the surgery group. There was no statistically significance between complication and success rates between two groups. Percutaneous Patent Ductus Arteriosus closure is the candidate for taking the place of surgery in preterms. However, it is not applied routinely; can only be done in fully equipped large centers by experienced interventionalists. Copyright © 2017 Elsevier B.V. All rights reserved.

Use of the Boomerang catalyst advantage closure device to facilitate complex multistaged percutaneous revascularization procedures for the treatment of critical limb ischemia.

PubMed

Garcia, Joel A; Casserly, Ivan P

2009-07-01

An increasing spectrum of complex peripheral arterial disease may be successfully treated using percutaneous revascularization techniques. A pair of challenging peripheral revascularization procedures in patients with critical limb ischemia is presented, where an array of interventional tools and techniques were required, and the off-label use of the Boomerang catalyst system closure device was important in managing a variety of complex arterial access issues and ultimately allowing procedural success. Copyright 2009 Wiley-Liss, Inc.

Device for testing closure disks at high rates of change of pressure

DOEpatents

Merten, C.W. Jr.

1993-11-09

A device is described for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A means is also disclosed for transmitting a tensile load from a piston to a hollow notched plug and for sealing the means for transmitting load within a hole in a piston. 5 figures.

Catheter-based closure of the patent ductus arteriosus in lower weight infants.

PubMed

Pavlek, Leeann R; Slaughter, Jonathan L; Berman, Darren P; Backes, Carl H

2018-06-13

Risks associated with drug therapy and surgical ligation have led health care providers to consider alternative strategies for patent ductus arteriosus (PDA) closure. Catheter-based PDA closure is the procedure of choice for ductal closure in adults, children, and infants ≥6kg. Given evidence among older counterparts, interest in catheter-based closure of the PDA in lower weight (<6kg) infants is growing. Among these smaller infants, the goals of this review are to: (1) provide an overview of the procedure; (2) review the types of PDA closure devices; (3) review the technical success (feasibility); (4) review the risks (safety profile); (5) discuss the quality of evidence on procedural efficacy; (6) consider areas for future research. The review provided herein suggests that catheter-based PDA closure is technically feasible, but the lack of comparative trials precludes determination of the optimal strategy for ductal closure in this subgroup of infants. Copyright © 2018 Elsevier Inc. All rights reserved.

Synchronous response modelling and control of an annular momentum control device

NASA Astrophysics Data System (ADS)

Hockney, Richard; Johnson, Bruce G.; Misovec, Kathleen

1988-08-01

Research on the synchronous response modelling and control of an advanced Annular Momentun Control Device (AMCD) used to control the attitude of a spacecraft is described. For the flexible rotor AMCD, two sources of synchronous vibrations were identified. One source, which corresponds to the mass unbalance problem of rigid rotors suspended in conventional bearings, is caused by measurement errors of the rotor center of mass position. The other sources of synchronous vibrations is misalignment between the hub and flywheel masses of the AMCD. Four different control algorithms were examined. These were lead-lag compensators that mimic conventional bearing dynamics, tracking notch filters used in the feedback loop, tracking differential-notch filters, and model-based compensators. The tracking differential-notch filters were shown to have a number of advantages over more conventional approaches for both rigid-body rotor applications and flexible rotor applications such as the AMCD. Hardware implementation schemes for the tracking differential-notch filter were investigated. A simple design was developed that can be implemented with analog multipliers and low bandwidth, digital hardware.

Synchronous response modelling and control of an annular momentum control device

NASA Technical Reports Server (NTRS)

Hockney, Richard; Johnson, Bruce G.; Misovec, Kathleen

1988-01-01

Research on the synchronous response modelling and control of an advanced Annular Momentun Control Device (AMCD) used to control the attitude of a spacecraft is described. For the flexible rotor AMCD, two sources of synchronous vibrations were identified. One source, which corresponds to the mass unbalance problem of rigid rotors suspended in conventional bearings, is caused by measurement errors of the rotor center of mass position. The other sources of synchronous vibrations is misalignment between the hub and flywheel masses of the AMCD. Four different control algorithms were examined. These were lead-lag compensators that mimic conventional bearing dynamics, tracking notch filters used in the feedback loop, tracking differential-notch filters, and model-based compensators. The tracking differential-notch filters were shown to have a number of advantages over more conventional approaches for both rigid-body rotor applications and flexible rotor applications such as the AMCD. Hardware implementation schemes for the tracking differential-notch filter were investigated. A simple design was developed that can be implemented with analog multipliers and low bandwidth, digital hardware.

Tissue loads applied by a novel medical device for closing large wounds.

PubMed

Katzengold, Rona; Topaz, Moris; Gefen, Amit

2016-02-01

Closure of large soft tissue defects following surgery or trauma as well as closure of large chronic wounds constitutes substantial but common reconstructive challenges. In such cases, an attempt to use conventional suturing will result in high-tension closure, therefore alternative external skin stretching systems were developed. These types of devices were meant to reduce local mechanical loads in the skin and the underlying tissues, taking advantage of the viscoelastic properties of the skin, especially mechanical creep, for primary wound closure. Studies have shown the clinical advantages of skin stretching systems, however, quantitative bioengineering models, demonstrating closure of large wounds, are lacking. Here we present finite element (FE) modeling of the TopClosure(®) tension relief system (TRS) and its biomechanical efficacy in three (real) wound cases, compared with the alternative of a conventional surgical suturing closure technique. Our simulations showed that peak effective stresses on the skin were at least an order of magnitude greater (and sometimes nearly 2 orders-of-magnitude greater) when tension sutures were used with respect to the corresponding TRS data. For the tension suture simulations, the tensile stress was in the range of 415-648 MPa and in the TRS simulations, it was 16-30 MPa. Based on the present computational FE modeling, the TRS reduces localized tissue deformations and stress concentrations in skin and underlying tissues while closing large wounds, compared to the deformations and stresses that are inflicted during the process of suturing. This substantial reduction of loads allows surgeons to better employ the viscoelastic properties of the skin for primary wound closure. Copyright © 2015 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

Closure of tubular patent ductus arteriosus with the Amplatzer Vascular Plug IV: feasibility and safety.

PubMed

Baruteau, Alban-Elouen; Lambert, Virginie; Riou, Jean-Yves; Angel, Claude-Yves; Belli, Emre; Petit, Jérôme

2015-01-01

Closure of tubular patent ductus arteriosus remains a challenging procedure. Anecdotal use of Amplatzer Vascular Plug IV for tubular ductus closure has been reported but feasibility and safety in a consecutive patients' series remain unknown. We performed a monocenter prospective study at the Marie Lannelongue Hospital in Paris, France. From 2009 to 2014, a total of 47 patients (39 infants, 3 children, and 5 adults) underwent ductus closure with the Plug IV. Ductus morphology was a type E in 34 (72.3%) patients and a type C in 13 (27.7%) patients. Ductus closure occurred in 39 (83.0%) infants at a median age of seven months (range: 3-23 months) and a median weight of 6.9 kg (range: 4.1-17.0 kg). A past history of prematurity and very low birth weight was found in 33 (70.2%) of them. Twelve (25.5%) patients had pulmonary hypertension. Mean Plug IV diameter was 1.9 ± 0.1 mm larger than the mean maximal ductus diameter. Early complete closure of the ductus was obtained in all patients. Early migration of an undersized Plug IV occurred in one (2.1%) patient and was suitable for percutaneous device retrieval. After a mean follow-up of 3.4 ± 1.4 years, all patients are alive and asymptomatic, no late complication occurred. Transcatheter closure of tubular ductus with the Amplatzer Vascular Plug IV can be safe and effective, with a 100% early occlusion rate. This device, suitable for a 4F sheath, is a new alternative for tubular ductus closure in low-body-weight infants. © The Author(s) 2014.

Effect of transcatheter closure of baffle leaks following senning or mustard atrial redirection surgery on oxygen saturations and polycythaemia.

PubMed

Bentham, James; English, Kate; Hares, Dominic; Gibbs, John; Thomson, John

2012-10-01

The aim of this study was to describe the clinical importance and methods of transcatheter closure of systemic venous baffle leaks after atrial redirection procedures for transposed great vessels. Until the late 1970s, atrial redirection surgery was the principal surgical palliative approach to manage transposed great vessels. Baffle leaks are among the many long-term complications of this type of surgery, and their prevalence increases over time. The clinical consequences of baffle leaks in this population are poorly understood, and the indications for closure are incompletely defined. During outpatient follow-up of 126 patients after atrial redirection surgery, 15 baffle leaks were detected in 11 patients. All underwent transcatheter closure using either an occluding device or a covered stent if there was concomitant baffle obstruction. The average age at the time of the procedure was 26 years (range 6 to 42). Ten of 11 patients were cyanosed at rest or on a simple walk test (median oxygen saturation level 80%, range 65% to 96%). Six of 11 patients were polycythemic before leak closure (median hemoglobin concentration 19 g/dl, range 13.8 to 23). After closure, there was a significant improvement in saturation (median 97%, p <0.0001) and a significant reduction in hemoglobin concentration at 6 months after the procedure (median 14.8 g/dl, p <0.05). There were no procedural adverse events. One patient experienced late device embolization necessitating surgical removal. In conclusion, transcatheter closure of baffle leaks is a technically feasible although frequently complex and lengthy procedure. Closure is associated with an improvement in oxygen saturations and a reduction in polycythaemia. Copyright © 2012 Elsevier Inc. All rights reserved.

Results of the combined U.S. Multicenter Pivotal Study and the Continuing Access Study of the Nit-Occlud PDA device for percutaneous closure of patent ductus arteriosus.

PubMed

Moore, John W; Greene, Jessica; Palomares, Salvadore; Javois, Alexander; Owada, Carl Y; Cheatham, John P; Hoyer, Mark H; Jones, Thomas K; Levi, Daniel S

2014-12-01

This study aimed to compare the efficacy and safety of the Nit-Occlud PDA device (PFM Medical, Cologne, Germany) to benchmarks designed as objective performance criteria (OPC). The Nit-Occlud PDA is a nitinol coil-type patent ductus arteriosus (PDA) occluder with a reverse cone configuration, which is implanted using a controlled delivery system. Patients with <4-mm minimum diameter PDA were prospectively enrolled in the Pivotal and the Continuing Access Studies from 15 sites in the United States and were followed up for 12 months post-procedure. Investigator-reported outcomes were compared to OPC including a composite success criterion, efficacy criteria of successful closure (clinical and echocardiographic), and safety criteria incidence of adverse events (serious and of total). The Pivotal Study enrolled patients between November 1, 2002 and October 31, 2005, and the Continuing Access Study enrolled additional patients between September 1, 2006 and October 31, 2007. A total of 357 patients were enrolled, and 347 had successful device implantations. After 12 months, 96.8% had complete echocardiographic closure (OPC = 85%) and 98.1% had clinical closure (OPC = 95%). There were no deaths or serious adverse events (OPC = 1%). The total adverse event rate was 4.7% (OPC = 6%). Composite success was 95.1% in the study patients (OPC = 80%). Closure of small- and medium-sized PDA with the Nit-Occlud PDA is effective and safe when compared with OPC. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Transcatheter closure of atrial septal defect with amplatzer septal occluder in adults: immediate, short, and intermediate-term results.

PubMed

Behjati, Mostafa; Rafiei, Mansour; Soltani, Mohammad Hossein; Emami, Mahmoud; Dehghani, Majid

2011-01-01

The transcatheter closure of the atrial septal defect (ASD) has become an alternative technique to surgical procedures. The aim of this study was to assess the immediate, short, and intermediate-term results of the transcatheter closure of the secundum ASD with the Amplatzer Septal Occluder (ASO) in adult Iranian patients. Between December 2004 and July 2008, the transcatheter closure of the ASD using the ASO was attempted in 58 consecutive, adult patients. The mean age of the patients was 37.1 ± 12.7 years (range = 19 - 75 years). All the procedures were performed under local anesthesia with transthoracic or transesophageal echocardiography and fluoroscopic guidance. The stretched diameter of the ASD was determined with a balloon sizing catheter, and device selection was based on and matched to the stretched diameter of the septal defect. Transthoracic echocardiography was performed immediately after the release of the device and before discharge. Further follow-up at one month, six months, and yearly thereafter included physical examination, electrocardiography, and transthoracic echocardiography. The mean ASD diameter, as measured by esophageal echocardiography, was 24.8 ± 5.4 mm (range = 13 - 34 mm). The mean stretched diameter, as measured by the balloon catheter, was 27.1 ± 6.4 mm (range = 12.5 - 39 mm). Deployment of the ASO was successful in 52 (89.6%) patients and failed in 6 (10.4%). Four patients experienced severe complications, 1 had tamponade requiring drainage, 2 had device embolization to the left atrium and right ventricular outflow tract, and 1 had late wire fracture (surgical removal and repair of the ASD). The position of two large devices (34 mm and 36 mm) was considered unsuitable and unstable after implantation and resulted in the removal of these devices. Minor complications included transient complete atrioventricular block in 1 patient, paroxysmal supra tachycardia in 3 patients, atrial flutter in 1 patient, and angina pectoris with transient ST elevation in 2 patients. The mean follow-up period was 32.5 ± 18.5 months. Echocardiography at 24 hours, 1 month, 6 months, and 12 months after the procedure showed residual shunts in 11 (21%), 3 (5.8%), 2 (3.8%), and 2 (3.8%) patients, respectively. At follow-up (12.8 months to 48.5 months, mean ± SD = 32.5 ± 18.5 months), complete closure was documented in 50 (96.2 %) of the 52 cases. At the end of the follow-up, 2 (3.8%) patients had residual shunts: The shunt was moderate in 1 (1.9%) patient and small in the other (1.9%). The overall success rate of the transcatheter closure of the ASD was 86% (50 of 58 cases). The transcatheter closure of the secundum ASD in our adult patient population using the ASO was associated with high degrees of success, minimal procedural complication rates, and excellent short and midterm results. The use of this device, however, requires thorough attention in that the procedure may be ineffective or the device may embolize. Further experience and long-term follow-up are required before a widespread clinical use can be recommended.

Comparison of effectiveness and cost of patent ductus arteriosus device occlusion versus surgical ligation of patent ductus arteriosus

PubMed Central

Zulqarnain, Arif; Younas, Muhammad; Waqar, Tariq; Beg, Ahsan; Asma, Touseef; Baig, Mirza Ahmad Raza

2016-01-01

Objectives: Comparison of effectiveness and cost of transcatheter occlusion of patent ductus arteriosus (PDA) with surgical ligation of PDA. Methods: This retrospective comparative study was conducted in the pediatric cardiology department of Ch. Pervaiz Elahi Institute of Cardiology Multan, Pakistan. Data of 250 patients who underwent patent ductus arteriosus (PDA) closure either surgical or trans-catheter closure using SHSMA Occluder having weight >5 kg from April 2012 to October 2015 were included in this study. SPSS version 20 was used for data analysis. Quantitative variables were compared using independent sample t-test. Chi-square test and fishers exact was used for qualitative variables. P-value <0.05 was considered statistically significant. Results: There were one hundred and twenty (120) patients who underwent transcatheter occlusion of PDA using SHSMA occluder (PDA Device Group) and one hundred and thirty (130) patients who underwent surgical ligation of PDA (Surgical Group). Incidence of residual shunting was two (1.5%) in surgical group and 0 (0.0%) in PDA Device group for one month follow up period. There were 4 (3.1%) major complications in surgical group. The rate of blood transfusions were high in surgical group (p-value 0.04). Hospital stay time was significantly less in PDA Device group (P-value <0.001). Total procedural cost was 110695+1054 Pakistani rupees in PDA Device group and 92414+3512 in surgical group (p-value <0.001). The cost of PDA device closure was 16.52% higher than the surgical ligation of PDA. There was no operative mortality. Conclusion: The transcatheter closure of PDA is an effective and less invasive method as compared to the surgical ligation. There is a lower rate of complications and the cost is not much high as compared to surgical PDA ligation. PMID:27648051

A novel one-shot circular stapler closure for atrial septal defect in a beating-heart porcine model.

PubMed

Tarui, Tatsuya; Tomita, Shigeyuki; Ishikawa, Norihiko; Ohtake, Hiroshi; Watanabe, Go

2015-02-01

In surgical atrial septal defect (ASD) closure, there are no techniques or devices that can close the ASD accurately in a short time under a beating heart. We have developed a simple and automatic ASD closure technique using a circular stapler. This study assessed the feasibility and efficacy of a new circular stapler closure for ASD. Under a continuous beating heart, hand-sewn patch plasty ASD closure was performed in 6 pigs (group A) and circular stapler ASD closure was performed in 6 pigs (group B). The time to close the ASD and the effectiveness of the closure were compared. Closure was significantly faster in group B (10.5 ± 1.0 seconds) than in group A (664 ± 10 seconds; p < 0.05). There was no leakage at the closure site, and sufficient tolerance was confirmed. A circular stapler can be used to treat ASD faster than hand-sewn patch plasty, with sufficient pressure tolerance in a beating heart porcine model. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Transcatheter closure of patent ductus arteriosus: 11 years of clinical experience in Cipto Mangunkusumo Hospital, Jakarta, Indonesia.

PubMed

Djer, Mulyadi M; Saputro, Dimas Dwi; Putra, Sukman Tulus; Idris, Nikmah Salamia

2015-06-01

Transcatheter closure of patent ductus arteriosus (PDA) has been suggested to be the standard treatment of PDA. Although, in general, the procedure shows a high successful rate, outcomes may vary among pediatric cardiology centers. To evaluate the effectiveness of transcatheter closure of PDA in Cipto Mangunkusumo Hospital, Jakarta, Indonesia, this was a retrospective study on patients who underwent transcatheter closure of PDA in Cipto Mangunkusumo Hospital during the period of 2002-2013. Hospital registry was reviewed and data about patients' characteristics, PDA severity, procedure, and outcomes were retrieved. There were 298 patients, of whom 90 were males, who underwent transcatheter closure of PDA during the study period. Median age was 3.4 years (1 months-18 years), and median body weight was 12 (3.6-59) kg. The diameter of PDA ranged from 1.1 to 15.4 mm with a median of 3.7 mm. Device could be deployed in all patients, in which most were the Amplatzer ductal occluder (69.8 %) and the remainders were coils. Median fluoroscopy time was 15.4 (1.5-87) min, and procedure time was 76 (30-200) min. Complete closure was achieved in most patients (97.3 %), whereas device migration occurred in a minority (0.3 %) of patients. No major complication occurred during or after the procedure. Transient anemia and bradycardia were found in 3.7 and 1.3 % patients, respectively. Most patients were discharged from the hospital at 1 day after the procedure. Transcatheter closure method is a safe and effective procedure to close PDA.

New devices and techniques for endoscopic closure of gastrointestinal perforations

PubMed Central

Li, Yue; Wu, Jian-Hua; Meng, Yan; Zhang, Qiang; Gong, Wei; Liu, Si-De

2016-01-01

Gastrointestinal perforations, which need to be managed quickly, are associated with high morbidity and mortality. Treatments used to close these perforations range from surgery to endoscopic therapy. Nowadays, with the development of new devices and techniques, endoscopic therapy is becoming more popular. However, there are different indications and clinical efficacies between different methods, because of the diverse properties of endoscopic devices and techniques. Successful management also depends on other factors, such as the precise location of the perforation, its size and the length of time between the occurrence and diagnosis. In this study, we performed a comprehensive review of various devices and introduced the different techniques that are considered effective to treat gastrointestinal perforations. In addition, we focused on the different methods used to achieve successful closure, based on the literature and our clinical experiences. PMID:27672268

Successful use of a left ventricular apical access and closure device for second-generation transapical aortic valve implantation.

PubMed

Conradi, Lenard; Seiffert, Moritz; Shimamura, Kazuo; Schirmer, Johannes; Blankenberg, Stefan; Reichenspurner, Hermann; Diemert, Patrick; Treede, Hendrik

2014-09-01

Transcatheter aortic valve implantation (TAVI) has become routine for the treatment of high-risk patients with aortic stenosis. We assessed safety and feasibility of a left ventricular apical access and closure device combined with second-generation transapical (TA) TAVI transcatheter heart valves (THV). Three elderly, comorbid patients (logEuroSCORE I 13.0-31.1%) received transapical aortic valve implantation (TA-AVI) via the Apica ASC device (Apica Cardiovascular Ltd., Galway, Ireland) using second-generation THV (Medtronic Engager [Medtronic 3F Therapeutics, Santa Ana, California, United States], JenaValve [JenaValve Technology GmbH, Munich, Germany], Symetis Acurate [Symetis S.A., Ecublens, Switzerland]). Access was gained using a non-rib-spreading technique and a novel access and closure device. THV deployment was successful with excellent hemodynamic outcome (no PVL, n = 2; trace PVL, n = 1; mean transvalvular gradients, 5-19 mm Hg) and complete apical hemostasis. No periprocedural major adverse events occurred and Valve Academic Research Consortium-2-defined composite end point of device success was met in all cases. Safety and feasibility of TA-AVI using the ASC device with second-generation THV was demonstrated. Combining latest available technology is a major step toward improved functional outcome and decreased surgical trauma in TA-AVI. Potentially, technical enhancements may eventually pave the way toward a fully percutaneous TA-AVI procedure. Georg Thieme Verlag KG Stuttgart · New York.

Laceration of the Common Femoral Artery Following Deployment of the StarClose{sup TM} Vascular Closure System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonsalves, Michael, E-mail: drmag1975@gmail.com; Walkden, Miles, E-mail: rwalkden@nhs.net; Belli, Anna Maria, E-mail: Anna.Belli@stgeorges.nhs.u

2008-07-15

StarClose is a novel arterial closure device which achieves hemostasis, following arteriotomy, via a nitinol clip deployed on the outer arterial wall. Since its introduction to the market, several studies have shown StarClose to be both safe and effective, with few major complications encountered. We report a case of common femoral artery laceration following deployment of the StarClose vascular closure system. We conclude that the injury occurred secondary to intravascular misplacement of the nitinol clip.

Transcatheter device closure of pseudoaneurysms of the left ventricular wall: An emerging therapeutic option.

PubMed

Madan, Tarun; Juneja, Manish; Raval, Abhishek; Thakkar, Bhavesh

2016-02-01

Left ventricular pseudoaneurysm is a rare but serious complication of acute myocardial infarction and cardiac surgery. While surgical intervention is the conventional therapeutic option, transcatheter closure can be considered in selected patients with suitable morphology of the pseudoaneurysm. We report a case of successful transcatheter closure of a left ventricular pseudoaneurysm orifice and isolation of the sac using an Amplatzer septal occluder. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Transcatheter closure of Patent Ductus Arteriosus through only venous route.

PubMed

Sheikh, Abdul Malik; Duke, Abdul Karim; Sattar, Hina

2018-03-01

Patent ductus arteriosus is a common congenital cardiac defect comprising 5-10% of all these defects in term neonates. Although open chest and video-assisted interruption are still in use, transcatheter occlusion has rapidly become the first choice for patent ductus arteriosus closure in the appropriate patient. Percutaneous closure of patent ductus arteriosus is widely done by transvenous approach guided by aortic access. We present the case of a 2 year old girl who underwent patent ductus arteriosus device occlusion with transvenous access only.

Transcatheter Closure of Patent Foramen Ovale in Patients with Platypnea-Orthodeoxia: Results of a Multicentric French Registry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guerin, P.; Lambert, V.; Godart, F.

Background. Dyspnea and the decrease in arterial saturation in the upright position in elderly subjects is described as platypnea-orthodeoxia syndrome (POS). POS is secondary to the occurrence of an atrial right-to-left shunt through a patent foramen ovale (PFO). Methods. This French multicentric study reports on 78 patients (mean age 67 {+-} 11.3 years) with POS who had transcatheter closure of the PFO; frequently associated diseases were pneumonectomy (n = 36) and an ascending aortic aneurysm (n = 11). In all patients, the diagnosis was confirmed by transthoracic or/and transesophageal echocardiography. Five different closure devices were used: Amplatz (n = 45),more » Cardioseal (n = 13), Sideris (n = 11), Das Angel Wings (n = 8) and Starflex (n = 1). Closure was successful in 76 patients (97%). Results. Oxygen saturation increased immediately after occlusion from 84.6 {+-} 10.7% to 95.1 {+-} 6.4% (p < 0.001) and dyspnea improved from grade 2.7 {+-} 0.7 to grade 1 {+-} 1 (p < 0.001). A small residual shunt was immediately observed in 5 patients (3 with the Cardioseal device, 1 with the Sideris and 1 with the Amplatz) leading to the implantation of a second device in one case (Cardioseal). Two early deaths occurred unrelated to the procedure (one due to sepsis probably related to pneumonectomy, another due to respiratory insufficiency). Other complications were: a small shunt between the aorta and the left atrium, two atrial fibrillations and a left-sided thrombus which disappeared with anticoagulant therapy. At a mean follow-up of 15 {+-} 12 months, there were 7 late deaths related to the underlying disease. Conclusion. Percutaneous occlusion of the foramen ovale is safe and gives excellent results thanks to continuing improvement in available devices. This technique enables some patients in an unstable condition to avoid a surgical closure.« less

Surgical repair of tricuspid valve leaflet tear following percutaneous closure of perimembranous ventricular septal defect using Amplatzer duct occluder I: Report of two cases

PubMed Central

Kuwelker, Saatchi Mahesh; Shetty, Devi Prasad; Dalvi, Bharat

2017-01-01

Tricuspid valve (TV) injury following transcatheter closure of perimembranous ventricular septal defect (PMVSD) with Amplatzer ductal occluder I (ADO I), requiring surgical repair, is rare. We report two cases of TV tear involving the anterior and septal leaflets following PMVSD closure using ADO I. In both the patients, the subvalvular apparatus remained unaffected. The patients presented with severe tricuspid regurgitation (TR) 6 weeks and 3 months following the device closure. They underwent surgical repair with patch augmentation of the TV leaflets. Postoperatively, both are asymptomatic with a mild residual TR. PMID:28163430

A new cable-tie based sternal closure system: description of the device, technique of implantation and first clinical evaluation

PubMed Central

2012-01-01

Background Wire closure still remains the preferred technique despite reasonable disadvantages. Associated complications, such as infection and sternal instability, cause time- and cost-consuming therapies. We present a new tool for sternal closure with its first clinical experience and results. Methods The sternal ZipFixTM System is based on the cable-tie principle. It primarily consists of biocompatible Poly-Ether-Ether-Ketone implants and is predominantly used peristernally through the intercostal space. The system provides a large implant-to-bone contact for better force distribution and for avoiding bone cut through. Results 50 patients were closed with the ZipFixTM system. No sternal instability was observed at 30 days. Two patients developed a mediastinitis that necessitated the removal of the device; however, the ZipFixTM were intact and the sternum remained stable. Conclusions In our initial evaluation, the short-term results have shown that the sternal ZipFixTM can be used safely and effectively. It is fast, easy to use and serves as a potential alternative for traditional wire closure. PMID:22731778

Acoustic streaming related to minor loss phenomenon in differentially heated elements of thermoacoustic devices

NASA Astrophysics Data System (ADS)

Mironov, Mikhail; Gusev, Vitalyi; Auregan, Yves; Lotton, Pierrick; Bruneau, Michel; Piatakov, Pavel

2002-08-01

It is demonstrated that the differentially heated stack, the heart of all thermoacoustic devices, provides a source of streaming additional to those associated with Reynolds stresses in quasi-unidirectional gas flow. This source of streaming is related to temperature-induced asymmetry in the generation of vortices and turbulence near the stack ends. The asymmetry of the hydrodynamic effects in an otherwise geometrically symmetric stack is due to the temperature difference between stack ends. The proposed mechanism of streaming excitation in annular thermoacoustic devices operates even in the absence of thermo-viscous interaction of sound waves with resonator walls. copyright 2002 Acoustical Society of America.

Resistor holder

DOEpatents

Broadhurst, John H.

1989-01-01

A resistor device for use with electrostatic particle accelerators includes a resistor element positioned within a tubular housing having a fixed end cap at one end thereof and a movable end cap at the other end thereof. The tubular housing, fixed end cap, and movable end cap serve as an electromagnetic field for the resistor element. Conductive disks engage opposite ends of the resistor element and concentrically position the resistor element within the tubular housing. Helical springs engage the conductive disks and the end caps to yieldably support the movable end caps and resistor element for yieldable axial movement relative to the tubular housing. An annular conducting ring is secured to the tubular housing and is spaced radially from the movable end cap and cooperates with the latter to define an annular spark gap.

Quality of life assessment in the randomized PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) trial of patients at risk for stroke with nonvalvular atrial fibrillation.

PubMed

Alli, Oluseun; Doshi, Shepal; Kar, Saibal; Reddy, Vivek; Sievert, Horst; Mullin, Chris; Swarup, Vijay; Whisenant, Brian; Holmes, David

2013-04-30

This study sought to assess quality of life parameters in a subset of patients enrolled in the PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) trial. The PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) trial demonstrated that in patients with nonvalvular atrial fibrillation (AF) and CHADS2 (congestive heart failure, hypertension, age, diabetes mellitus, and prior stroke, transient ischemic attack, or thromboembolism) score ≥1, a left atrial appendage closure device is noninferior to long-term warfarin for stroke prevention. Given this equivalency, quality of life (QOL) indicators are an important metric for evaluating these 2 different strategies. QOL using the Short-Form 12 Health Survey, version 2, measurement tool was obtained at baseline and 12 months in a subset of 547 patients in the PROTECT AF trial (361 device and 186 warfarin patients). The analysis cohort consisted of patients for whom either paired quality of life data were available after 12 months of follow-up or for patients who died. With the device, the total physical score improved in 34.9% and was unchanged in 29.9% versus warfarin in whom 24.7% were improved and 31.7% were unchanged (p = 0.01). Mental health improvement occurred in 33.0% of the device group versus 22.6% in the warfarin group (p = 0.06). There was a significant improvement in QOL in patients randomized to device for total physical score, physical function, and in physical role limitation compared to control. There were significant differences in the change in total physical score among warfarin naive and not-warfarin naive subgroups in the device group compared to control, but larger gains were seen with the warfarin naive subgroup with a 12-month change of 1.3 ± 8.8 versus -3.6 ± 6.7 (p = 0.0004) device compared to warfarin. Patients with nonvalvular AF at risk for stroke treated with left atrial appendage closure have favorable QOL changes at 12 months versus patients treated with warfarin. (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation [WATCHMAN PROTECT]; NCT00129545). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Prospective evaluation of the feasibility, safety, and efficacy of Cocoon Duct Occluder for transcatheter closure of large patent ductus arteriosus: A single-center study with short- and medium-term follow-up results

PubMed Central

Sinha, Santosh Kumar; Razi, Mahmadula; Pandey, Rama Niwas; Kumar, Prakash; Krishna, Vinay; Jha, Mukesh Jitendra; Mishra, Vikas; Asif, Mohammad; Abdali, Nasar; Tewari, Pradyot; Thakur, Ramesh; Pandey, Umeshwar; Varma, Chandra Mohan

2017-01-01

Objective: To evaluate the feasibility, safety, and efficacy of a novel Cocoon Duct Occluder device for the transcatheter closure (TCC) of large patent ductus arteriosus (PDA). Methods: In this prospective, non-randomized study, consecutive patients with large PDA (narrowest diameter: ≥3.5/4.0 mm in symptomatic/asymptomatic patients, respectively), who underwent TCC with Cocoon Duct Occluder at our institute between November, 2012 and June, 2016 were examined. TCC was performed using the standard technique, and devices were antegradely delivered via 6–10F delivery sheaths. Device embolization, residual shunt, hemolysis, left pulmonary artery (LPA) stenosis, procedural and fluoroscopy time, and mortality were assessed. Patients were followed-up by transthoracic echocardiography with color Doppler imaging at 24 h (D1), 1 month (D30), and 6 months (D180) after implantation. Results: A total of 57 patients (age: 11.7±2.8 years; weight: 22.3±3.5 kg) were enrolled. The mean narrowest diameter was 7.4±0.7 mm. The PDA closure was successfully performed in each patient. Fluoroscopy and procedural time was 6.7±3.2 min and 23.9±2.7 min, respectively. Postprocedural angiography revealed that 49 (85.9%) patients had immediate and complete closure, whereas 8 (14.1%) had residual shunt. Color Doppler imaging at D1 revealed complete closure in 52 (91.3%) patients. At D30, complete closure was reported in all patients and was maintained at D180. Hemolysis, embolization, obstruction of LPA or descending aorta, and death were not reported till D180. Conclusion: TCC using Cocoon Duct Occluder is feasible, safe, and effective in the management of patients with large PDA, with excellent results on short- and medium-term follow-up. PMID:29145233

A magnetic bearing control approach using flux feedback

NASA Technical Reports Server (NTRS)

Groom, Nelson J.

1989-01-01

A magnetic bearing control approach using flux feedback is described and test results for a laboratory model magnetic bearing actuator are presented. Test results were obtained using a magnetic bearing test fixture, which is also described. The magnetic bearing actuator consists of elements similar to those used in a laboratory test model Annular Momentum Control Device (AMCD).

Management of hidradenitis suppurativa wounds with an internal vacuum-assisted closure device.

PubMed

Chen, Y Erin; Gerstle, Theodore; Verma, Kapil; Treiser, Matthew D; Kimball, Alexandra B; Orgill, Dennis P

2014-03-01

Hidradenitis suppurativa is a chronic, debilitating disease that is difficult to treat. Once medical management fails, wide local excision offers the best chance for cure. However, the resultant wound often proves too large or contaminated for immediate closure. The authors performed a retrospective chart review of hidradenitis cases managed surgically between 2005 and 2010. Data collected included patient characteristics, management method, and outcomes. Approximately half of the patients received internal vacuum-assisted closure therapy using the vacuum-assisted closure system and delayed closure and half of the patients received immediate primary closure at the time of their excision. Delayed closure consisted of closing the majority of the wound in a linear fashion following internal vacuum-assisted closure while accepting healing by means of secondary intention for small wound areas. Patients managed with internal vacuum-assisted closure had wounds on average four times larger in area than patients managed without internal vacuum-assisted closure. In both groups, all wounds were eventually closed primarily. Healing times averaged 2.2 months with internal vacuum-assisted closure and 2.7 months without. At an average follow-up time of 2.3 months, all patients with internal vacuum-assisted closure had no recurrence of their local disease. Severe hidradenitis presents a treatment challenge, as surgical excisions are often complicated by difficult closures and unsatisfactory recurrence rates. This study demonstrates that wide local excision with reasonable outcomes can be achieved using accelerated delayed primary closure. This method uses internal vacuum-assisted closure as a bridge between excision and delayed primary closure, facilitating closure without recurrence in large, heavily contaminated wounds. Therapeutic, III.

Is the new Occlutech duct occluder an appropriate device for transcatheter closure of patent ductus arteriosus?

PubMed

Godart, François; Houeijeh, Ali; Domanski, Olivia; Guillaume, Marie-Paule; Brard, Mélanie; Lucron, Hugues

2018-06-15

To describe our initial experience with the Occlutech Duct Occluder (ODO) for percutaneous closure of patent ductus arteriosus (PDA). Retrospective review of patients undergoing transcatheter PDA closure with the ODO in 2 academic centers. From April 2013 to September 2017, 42 patients underwent PDA closure. Median age at implantation was 34 months (range 4 months-68 years) and median weight was 12 kg (range 4.1-57 kg). Ducts were Krichenko type A duct (n = 34), type E (n = 6), and type C (n = 2). The mean duct diameter was 3.76 mm (range 1.69 to 9.95 mm, median 3.1 mm). Implantation succeeded in all. There was neither device embolization nor hemolysis. At device release, immediate angiogram showed a small residual shunt in 54.7%. During follow-up, Doppler echocardiography demonstrated 71% of full occlusion at day one, rising to 95% at one month and 100% at one year and half after implantation. The mean maximal systolic pressure gradient in left pulmonary artery was 4.2 ± 4.3 mm and across the distal aortic arch 5.4 ± 4.7 mm Hg. No patient had any significant stenosis with clinical relevance. ODO is safe and effective in transcatheter closure of PDA including relatively large sized ducts. The results are satisfactory with a high level of full occlusion and a low rate of complications. Further evaluation with larger studies and longer follow-up will be required to confirm these preliminary good results. Copyright © 2018. Published by Elsevier B.V.

Gas powered fluid gun with recoil mitigation

DOEpatents

Grubelich, Mark C; Yonas, Gerold

2013-11-12

A gas powered fluid gun for propelling a stream or slug of a fluid at high velocity toward a target. Recoil mitigation is provided that reduces or eliminates the associated recoil forces, with minimal or no backwash. By launching a quantity of water in the opposite direction, net momentum forces are reduced or eliminated. Examples of recoil mitigation devices include a cone for making a conical fluid sheet, a device forming multiple impinging streams of fluid, a cavitating venturi, one or more spinning vanes, or an annular tangential entry/exit.

Gas powered fluid gun with recoil mitigation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grubelich, Mark C.; Yonas, Gerold

A gas powered fluid gun for propelling a stream or slug of a fluid at high velocity toward a target. Recoil mitigation is provided that reduces or eliminates the associated recoil forces, with minimal or no backwash. By launching a quantity of water in the opposite direction, net momentum forces are reduced or eliminated. Examples of recoil mitigation devices include a cone for making a conical fluid sheet, a device forming multiple impinging streams of fluid, a cavitating venturi, one or more spinning vanes, or an annular tangential entry/exit.

21 CFR 878.4011 - Tissue adhesive with adjunct wound closure device for topical approximation of skin.

Code of Federal Regulations, 2014 CFR

2014-04-01

... ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY... approximated skin edges of wounds from surgical incisions, including punctures from minimally invasive surgery...

21 CFR 878.4011 - Tissue adhesive with adjunct wound closure device for topical approximation of skin.

Code of Federal Regulations, 2012 CFR

2012-04-01

... ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY... approximated skin edges of wounds from surgical incisions, including punctures from minimally invasive surgery...

21 CFR 878.4011 - Tissue adhesive with adjunct wound closure device for topical approximation of skin.

Code of Federal Regulations, 2013 CFR

2013-04-01

... ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY... approximated skin edges of wounds from surgical incisions, including punctures from minimally invasive surgery...

Electrode geometry for electrostatic generators and motors

DOEpatents

Post, Richard F.

2016-02-23

An electrostatic (ES) device is described with electrodes that improve its performance metrics. Devices include ES generators and ES motors, which are comprised of one or more stators (stationary members) and one or more rotors (rotatable members). The stator and rotors are configured as a pair of concentric cylindrical structures and aligned about a common axis. The stator and rotor are comprised of an ensemble of discrete, longitudinal electrodes, which are axially oriented in an annular arrangement. The shape of the electrodes described herein enables the ES device to function at voltages significantly greater than that of the existing art, resulting in devices with greater power-handling capability and overall efficiency. Electrode shapes include, but are not limited to, rods, corrugated sheets and emulations thereof.

49 CFR 178.338-11 - Discharge control devices.

Code of Federal Regulations, 2011 CFR

2011-10-01

... water capacity, remote means of automatic closure must be installed at the ends of the cargo tank in at... control system. (ii) On a cargo tank motor vehicle of 3,500 gallons water capacity or less, at least one remote means of automatic closure must be installed on the end of the cargo tank farthest away from the...

A Quick Guide to Paravalvular Leak Closure

PubMed Central

Gafoor, Sameer; Franke, Jennifer; Bertog, Stefan; Lam, Simon; Vaskelyte, Laura; Hofmann, Ilona; Matic, Predrag

2015-01-01

Paravalvular leak (PVL) is a seldomly covered aspect of structural heart disease. However, this is a condition that frequently presents after valvular replacement. This article will cover the diagnosising and treating PVL (i.e. imaging, access, and device selection). In addition, specific aspects of aortic and mitral PVL closure will be covered in this review. PMID:29588686

Gas arc constriction for plasma arc welding

NASA Technical Reports Server (NTRS)

McGee, William F. (Inventor); Rybicki, Daniel J. (Inventor)

1994-01-01

A welding torch for plasma arc welding apparatus has an inert gas applied circumferentially about the arc column externally of the constricting nozzle so as to apply a constricting force on the arc after it has exited the nozzle orifice and downstream of the auxiliary shielding gas. The constricting inert gas is supplied to a plenum chamber about the body of the torch and exits through a series of circumferentially disposed orifices in an annular wall forming a closure at the forward end of the constricting gas plenum chamber. The constricting force of the circumferential gas flow about the arc concentrates and focuses the arc column into a more narrow and dense column of energy after exiting the nozzle orifice so that the arc better retains its energy density prior to contacting the workpiece.

Cost-Effectiveness of Percutaneous Closure of the Left Atrial Appendage in Atrial Fibrillation Based on Results from PROTECT AF vs. PREVAIL

PubMed Central

Freeman, James V.; Hutton, David W.; Barnes, Geoffrey D.; Zhu, Ruo P.; Owens, Douglas K.; Garber, Alan M.; Go, Alan S.; Hlatky, Mark A.; Heidenreich, Paul A.; Wang, Paul J.; Al-Ahmad, Amin; Turakhia, Mintu P.

2016-01-01

Background Randomized trials of left atrial appendage (LAA) closure with the Watchman device have shown varying results, and its cost-effectiveness compared to anticoagulation has not been evaluated using all available contemporary trial data. Methods and Results We used a Markov decision model to estimate lifetime quality-adjusted survival, costs, and cost-effectiveness of LAA closure with Watchman, compared directly with warfarin and indirectly with dabigatran, using data from the long-term (mean 3.8 year) follow-up of PROTECT AF and PREVAIL randomized trials. Using data from PROTECT AF, the incremental cost-effectiveness ratios (ICER) compared to warfarin and dabigatran were $20,486 and $23,422 per quality adjusted life year (QALY), respectively. Using data from PREVAIL, LAA closure was dominated by warfarin and dabigatran, meaning that it was less effective (8.44, 8.54, and 8.59 QALYs, respectively) and more costly. At a willingness-to-pay-threshold of $50,000 per QALY, LAA closure was cost-effective 90% and 9% of the time under PROTECT AF and PREVAIL assumptions, respectively. These results were sensitive to the rates of ischemic stroke and intracranial hemorrhage for LAA closure and medical anticoagulation. Conclusions Using data from the PROTECT AF trial, LAA closure with the Watchman device was cost-effective; using PREVAIL trial data, Watchman was more costly and less effective than warfarin and dabigatran. PROTECT AF enrolled more patients and has substantially longer follow-up time, allowing greater statistical certainty with the cost-effectiveness results. However, longer term trial results and post-marketing surveillance of major adverse events will be vital to determining the value of the Watchman in clinical practice. PMID:27307517

Permanent Magnet Ecr Plasma Source With Magnetic Field Optimization

DOEpatents

Doughty, Frank C.; Spencer, John E.

2000-12-19

In a plasma-producing device, an optimized magnet field for electron cyclotron resonance plasma generation is provided by a shaped pole piece. The shaped pole piece adjusts spacing between the magnet and the resonance zone, creates a convex or concave resonance zone, and decreases stray fields between the resonance zone and the workpiece. For a cylindrical permanent magnet, the pole piece includes a disk adjacent the magnet together with an annular cylindrical sidewall structure axially aligned with the magnet and extending from the base around the permanent magnet. The pole piece directs magnetic field lines into the resonance zone, moving the resonance zone further from the face of the magnet. Additional permanent magnets or magnet arrays may be utilized to control field contours on a local scale. Rather than a permeable material, the sidewall structure may be composed of an annular cylindrical magnetic material having a polarity opposite that of the permanent magnet, creating convex regions in the resonance zone. An annular disk-shaped recurve section at the end of the sidewall structure forms magnetic mirrors keeping the plasma off the pole piece. A recurve section composed of magnetic material having a radial polarity forms convex regions and/or magnetic mirrors within the resonance zone.

A Prospective, Randomized, Double-Blind Multicenter Study Comparing Continuous Diffusion of Oxygen Therapy to Sham Therapy in the Treatment of Diabetic Foot Ulcers.

PubMed

Niederauer, Mark Q; Michalek, Joel E; Armstrong, David G

2017-09-01

Over the past generation, preclinical data have suggested that there is a potential physiologic benefit to applying oxygen topically to wounds. However, we are unaware of any studies in the literature that have robustly assessed whether this would lead to a higher proportion of healing in similarly treated people without oxygen. Therefore, the purpose of this study was to assess this in people being treated for chronic diabetic foot ulcers (DFUs). We enrolled and randomized 100 subjects with DFUs (79% male, aged 58.3 ± 12.1 years) to receive either active continuous diffusion of oxygen (CDO) therapy using an active CDO device, or an otherwise fully operational sham device that provided moist wound therapy (MWT) without delivering oxygen. Patients were followed until closure or 12 weeks, whichever was sooner. Patients, treating physicians and independent evaluators were blinded to the study arm. All patients received identical offloading, dressings and follow-up. There were no significant differences in assessed descriptive characteristics between the treatment arms ( P > .05 for all). A significantly higher proportion of people healed in the active arm compared to sham (46% vs 22%, P = .02). This relative effect became greater in more chronic wounds (42.5% vs 13.5%, P = .006). Patients randomized to the active device experienced significantly faster rates of closure relative to the sham ( P < .001). The results of this study suggest that continuously diffused oxygen over a wound leads to significantly higher rates of closure, and faster time to closure, compared to similarly treated patients receiving standard therapy coupled with a sham device. Furthermore, the relative efficacy appears to improve the more the therapy may be needed (more chronic and larger wounds).

Transcatheter closure of patent ductus arteriosus using the AMPLATZER™ duct occluder II (ADO II).

PubMed

Gruenstein, Daniel H; Ebeid, Makram; Radtke, Wolfgang; Moore, Phillip; Holzer, Ralf; Justino, Henri

2017-05-01

The study purpose is to evaluate the safety and efficacy of the ADO II device for closure of patent ductus arteriosus (PDA) in children. Transcatheter treatment of PDA has been evolving for 40+ years and is the treatment of choice. The AMPLATZER™ Duct Occluder (ADO) device was developed for larger diameter ducts and is not ideal in all PDAs. ADO II was developed for small to moderate-sized ducts. This is a single-arm, multicenter study evaluating safety and efficacy of the ADO II device. Patients <18 years were screened for a PDA ≤5.5 mm in diameter and 3-12 mm in length. Right and left heart catheterization was performed, and hemodynamic data were obtained at the time of implant. The diameter of the left pulmonary artery (LPA) and descending aorta, and the presence of any pre-existing pressure gradients across the LPA or aortic arch were assessed at baseline and 6 months post-implant. A total of 192 patients were enrolled. The median implant time was 74 min. Median fluoroscopy time was 12 min. A retrograde (aortic) approach was used in 33% of procedures and demonstrated a statistically significant reduction in fluoroscopy time (P value = 0.0018) compared to an antegrade approach. The device was successfully implanted in 93% of patients, with complete closure in 98% of successful implantations. In this prospective study, the ADO II was safe and effective for closure of small to moderate PDAs. Implantation is simple and the ability for retrograde aortic delivery reduces procedure-related radiation exposure. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Percutaneous treatment of atrial septal defects, muscular ventricular septal defects and patent ductus arteriosus in infants under one year of age.

PubMed

Prada, Fredy; Mortera, Carlos; Bartrons, Joaquim; Rissech, Miguel; Jiménez, Lorenzo; Carretero, Juan; Llevadias, Judit; Araica, Mireya

2009-09-01

Amplatzer devices are used for the percutaneous closure of ostium secundum atrial septal defects, muscular ventricular septal defects and patent ductus arteriosus. However, very little experience has been gained in using these devices in infants under 1 year of age. Between January 2001 and January 2008, 22 symptomatic infants aged under 1 year underwent percutaneous treatment: three had an ostium secundum atrial septal defect, 15 had patent ductus arteriosus, and four had a muscular ventricular septal defect. All the procedures were completed successfully. No immediate or medium-term complications were observed. Closure of these types of defect using an Amplatzer device in infants under 1 year of age, who would otherwise require surgery, is a safe and effective procedure.

78 FR 67365 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-12

... reduce the risk of life-threatening bleeding events in patients with non-valvular atrial fibrillation who... premarket approval application regarding the Boston Scientific WATCHMAN Left Atrial Appendage (LAA) Closure... placed in the left atrial appendage. This device is intended to prevent thrombus embolization from the...

Options for Closure of the Infected Abdomen

PubMed Central

Campbell, Chris A.; Rosenberger, Laura H.; Politano, Amani D.; Davies, Stephen W.; Riccio, Lin M.; Sawyer, Robert G.

2012-01-01

Abstract Background The infected abdomen poses substantial challenges to surgeons, and often, both temporary and definitive closure techniques are required. We reviewed the options available to close the abdominal wall defect encountered frequently during and after the management of complicated intra-abdominal infections. Methods A comprehensive review was performed of the techniques and literature on abdominal closure in the setting of intra-abdominal infection. Results Temporary abdominal closure options include the Wittmann Patch, Bogota bag, vacuum-assisted closure (VAC), the AbThera™ device, and synthetic or biologic mesh. Definitive reconstruction has been described with mesh, components separation, and autologous tissue transfer. Conclusion Reconstructing the infected abdomen, both temporarily and definitively, can be accomplished with various techniques, each of which is associated with unique advantages and disadvantages. Appropriate judgment is required to optimize surgical outcomes in these complex cases. PMID:23216525

Design, Construction and Testing of Annular Diffusers for High Speed Civil Transportation Combustor Applications

NASA Technical Reports Server (NTRS)

Okhio, Cyril B.

1996-01-01

A theoretical and an experimental design study of subsonic flow through curved-wall annular diffusers has been initiated under this award in order to establish the most pertinent design parameters and hence performance characteristics for such devices, an the implications of their application in the design of engine components in the aerospace industries. The diffusers under this study are expected to contain appreciable regions of stall and the effects of swirl on their performance are being studied. The experimental work involves the application of Computer Aided Design software tool to the development of a suitable annular diffuse geometry and the subsequent downloading of such data to a CNC machine at Central State University (CSU). Two experimental run segments have been completed so far during FY-95 involving flow visualization and diffuser performance evaluation based on Kinetic Energy Dissipation. The method of calculation of the performance of diffusers based on pressure recovery coefficient has been shown to have some shortcomings and so the kinetic energy dissipation approach has been introduced in the run segment two with some success. The application of the discretized, full Navier Stokes and Continuity equations to the numerical study of the problem described above for the time-mean flow is expected to follow. Various models of turbulence are being evaluated for adoption throughout the study and comparisons would be made with experimental data where they exist. Assessment of diffuser performance based on the dissipated mechanical energy would also be made. The result of the investigations are expected to indicate that more cost effective component design of such devices as diffusers which normally contain complex flows can still be achieved.

Arrhythmias after transcatheter closure of perimembranous ventricular septal defects with a modified double-disk occluder: early and long-term results.

PubMed

Li, Pan; Zhao, Xian-xian; Zheng, Xing; Qin, Yong-wen

2012-07-01

With the development of interventional techniques and devices, transcatheter closure of perimembranous ventricular septal defect has been widely performed. However, there has been a lack of long-term follow-up results about postoperative ECG changes of PmVSD patients. We report our experience of early and late arrhythmias after transcatheter closure of PmVSD with a modified double-disk occluder (MDVO). We performed a retrospective review of 79 patients (47 males, 32 females) between September 2002 and May 2007 who underwent transcatheter closure of perimembranous ventricular septal defect. Symmetric and asymmetric PmVSD occluders were used. The diameter of the evaluated defects ranged from 3 to 12 mm, as measured by TTE and 3 to 15 mm by left ventriculography. Most cases of PmVSD were treated successfully with a single procedure, resulting in a successful closure rate of 97% (77/79 patients). There was no death in any of the patients. After the operation, 79 patients were followed-up for a range of 10-76 months (35.3 ± 17.4 months). In this series, 11 cases of incomplete right bundle branch block and five cases of complete right bundle branch block occurred during the early period after operation. During long-term follow-up, these issues declined in prevalence to five and four cases, respectively. Moreover, reversible third-degree AVB occurred during closure or after the procedure, and two of the three patients with reversible AVB received a temporary heart pacemaker implantation. These patients recovered 1 h, 6 days, and 9 days later, respectively. During 10-76 months of follow-up, no complications occurred in any of the patients, including residual shunt, severe aortic valve, or tricuspid valve regurgitation. Device closure of perimembranous ventricular septal defects with a modified double-disk occluder (MDVO) resulted in excellent closure rates and acceptably low arrhythmia rates.

The Impact of Turtle Excluder Devices and Fisheries Closures on Loggerhead and Kemp's Ridley Strandings in the Western Gulf of Mexico

USGS Publications Warehouse

Lewison, R.L.; Crowder, L.B.; Shaver, D.J.

2003-01-01

The Sea Turtle Stranding and Salvage Network has been monitoring turtle strandings for more than 20 years in the United States. High numbers of strandings in the early to mid-1980s prompted regulations to require turtle excluder devices (TEDs) on shrimping vessels (trawlers). Following year-round TED implementation in 1991, however, stranding levels in the Gulf of Mexico increased. We evaluated the efficacy of TEDs and other management actions (e.g., fisheries closures) on loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) turtle populations by analyzing a long-term, stranding data set from the western Gulf of Mexico. Our analyses suggest that both sea turtle population growth and shrimping activity have contributed to the observed increase in strandings. Compliance with regulations requiring turtle excluder devices was a significant factor in accounting for annual stranding variability: low compliance was correlated with high levels of strandings. Our projections suggest that improved compliance with TED regulations will reduce strandings to levels that, in conjunction with other protective measures, should promote population recoveries for loggerhead and Kemp's ridley turtles. Local, seasonal fisheries closures, concurrent with TED enforcement, could reduce strandings to even lower levels. A seasonal closure adjacent to a recently established Kemp's ridley nesting beach may also reduce mortality of nesting adults and thus promote long-term population persistence by fostering the establishment of a robust secondary nesting site.

Transcatheter closure of atrial septal defects type 2 in children under 3 years of age.

PubMed

Knop, Mateusz T; Białkowski, Jacek; Szkutnik, Małgorzata; Fiszer, Roland; Smerdziński, Sebastian; Gałeczka, Michał; Litwin, Linda

2018-06-04

Atrial septal defect type II (ASD), according to current standards, is closed percutaneously usually after the child has reached the age of 4-5 years. There are limited data regarding such treatment in smaller infants. To evaluate feasibility, safety and efficacy of percutaneous ASD closure in children under 3 years of age. Overall group of 149 children < 3 years with hemodynamically significant ASD, who underwent effective transcatheter ASD closure in one tertiary center between 1999 and 2014 were included. Mean procedural age of treated children was 2,2 years and weight 12,5 kg. In all nitinol wire mesh devices were applied (mostly Amplatzer Septal Occluders). ASD was closed by standard technique (except few cases when left disc of implant was inserted initially into right pulmonary vein to prevent oblique position of the device). Complications related to the procedure were divided into major and minor ones. There were 97 children with a single ASD and 52 with double/multiple ASD. No death, no implant embolization, and one major complications occurred during procedure and in follow-up. ASD was completely closed in all but 8 patients with double/multiple ASD. Right ventricle diameter normalization occurred in all during 1 year follow-up. In majority of the patients in follow-up an acceleration of physical development and resolution of accompanying morbidity was observed. Percutaneous ASD device closure can be performer safely in children below 3 years of age with low risk of complication during and after the procedure.

Hybrid approach to surgical correction of tetralogy of Fallot in all patients with functioning Blalock Taussig shunts.

PubMed

Sivakumar, Kothandam; Krishnan, Prasad; Pieris, Rajeeva; Francis, Edwin

2007-08-01

In total surgical correction of tetralogy of Fallot (TOF) with functioning Blalock Taussig shunts (BTS), shunt take down increased surgical time, bleeding, and might injure phrenic and recurrent laryngeal nerve and thoracic duct. A routine hybrid approach using transcatheter BTS closure immediately before total surgical correction of TOF in all patients might reduce these problems. We analyze the safety and feasibility of this approach. Transcatheter BTS closure was achieved using single or multiple stainless steel embolization coils, Amplatzer vascular plugs, or duct occluders. When coils were released without control by bioptome forceps, coil migration in larger shunts was prevented by proximal or distal balloon occlusion. This routine hybrid strategy was followed in 22 consecutive patients aged 1-13 years over 4-year-period and 21 procedures were successful. Among the 16 patients attempted with coils, 13 had successful closure, 2 needed Amplatzer duct occluder devices, and 1 sent for surgical shunt takedown due to acute angulation of the shunt. New Amplatzer vascular plugs were used in six patients. Bioptome was used in six patients and proximal or distal balloon occlusion of flow was used in three patients. Four patients had closure of associated aortopulmonary or chest wall collaterals. Hybrid approach using routine transcatheter closure of all BTS immediately before surgical correction of TOF shunts with coils/plugs/devices is safe, feasible, and reproducible. Copyright (c) 2007 Wiley-Liss, Inc.

A megawatt-level surface wave oscillator in Y-band with large oversized structure driven by annular relativistic electron beam.

PubMed

Wang, Jianguo; Wang, Guangqiang; Wang, Dongyang; Li, Shuang; Zeng, Peng

2018-05-03

High power vacuum electronic devices of millimeter wave to terahertz regime are attracting extensive interests due to their potential applications in science and technologies. In this paper, the design and experimental results of a powerful compact oversized surface wave oscillator (SWO) in Y-band are presented. The cylindrical slow wave structure (SWS) with rectangular corrugations and large diameter about 6.8 times the radiation wavelength is proposed to support the surface wave interacting with annular relativistic electron beam. By choosing appropriate beam parameters, the beam-wave interaction takes place near the π-point of TM 01 mode dispersion curve, giving high coupling impedance and temporal growth rate compared with higher TM 0n modes. The fundamental mode operation of the device is verified by the particle-in-cell (PIC) simulation results, which also indicate its capability of tens of megawatts power output in the Y-band. Finally, a compact experimental setup is completed to validate our design. Measurement results show that a terahertz pulse with frequency in the range of 0.319-0.349 THz, duration of about 2 ns and radiation power of about 2.1 MW has been generated.

A highly attenuating and frequency tailorable annular hole phononic crystal for surface acoustic waves.

PubMed

Ash, B J; Worsfold, S R; Vukusic, P; Nash, G R

2017-08-02

Surface acoustic wave (SAW) devices are widely used for signal processing, sensing and increasingly for lab-on-a-chip applications. Phononic crystals can control the propagation of SAW, analogous to photonic crystals, enabling components such as waveguides and cavities. Here we present an approach for the realisation of robust, tailorable SAW phononic crystals, based on annular holes patterned in a SAW substrate. Using simulations and experiments, we show that this geometry supports local resonances which create highly attenuating phononic bandgaps at frequencies with negligible coupling of SAWs into other modes, even for relatively shallow features. The enormous bandgap attenuation is up to an order-of-magnitude larger than that achieved with a pillar phononic crystal of the same size, enabling effective phononic crystals to be made up of smaller numbers of elements. This work transforms the ability to exploit phononic crystals for developing novel SAW device concepts, mirroring contemporary progress in photonic crystals.The control and manipulation of propagating sound waves on a surface has applications in on-chip signal processing and sensing. Here, Ash et al. deviate from standard designs and fabricate frequency tailorable phononic crystals with an order-of-magnitude increase in attenuation.

The modeling and design of the Annular Suspension and Pointing System /ASPS/. [for Space Shuttle

NASA Technical Reports Server (NTRS)

Kuo, B. C.; Lin, W. C. W.

1979-01-01

The Annular Suspension and Pointing System (ASPS) is a payload auxiliary pointing device of the Space Shuttle. The ASPS is comprised of two major subassemblies, a vernier and a coarse pointing subsystem. The three functions provided by the ASPS are related to the pointing of the payload, centering the payload in the magnetic actuator assembly, and tracking the payload mounting plate and shuttle motions by the coarse gimbals. The equations of motion of a simplified planar model of the ASPS are derived. Attention is given to a state diagram of the dynamics of the ASPS with position-plus-rate controller, the nonlinear spring characteristic for the wire-cable torque of the ASPS, the design of the analog ASPS through decoupling and pole placement, and the time response of different components of the continuous control system.

Wide acceptance angle, high concentration ratio, optical collector

NASA Technical Reports Server (NTRS)

Kruer, Mark A. (Inventor)

1991-01-01

A cassegrain optical system provides improved collection of off-axis light yet is still characterized by a high concentration ratio. The optical system includes a primary mirror for collecting incoming light and reflecting the light to a secondary mirror which, in turn, reflects the light to a solar cell or other radiation collection device. The primary mirror reflects incoming on-axis light onto an annular section of the secondary mirror and results in the reflection of a substantial amount of incoming off-axis light onto the remainder of the secondary mirror. Thus light which would otherwise be lost to the system will be captured by the collector. Furthermore, the off-axis sections of the secondary mirror may be of a different geometrical shape than the on-axis annular section so as to optimize the amount of off-axis light collected.

Transcatheter closure of moderate-to-large patent ductus arteriosus in infants using Amplatzer duct occluder.

PubMed

Wang, Jou-Kou; Wu, Mei-Hwan; Lin, Ming-Tai; Chiu, Shuenn-Nan; Chen, Chun-An; Chiu, Hsin-Hui

2010-02-01

There are difficulties in transcatheter closure of patent ductus arteriosus (PDA) in infants. The 46 infants (mean age 6.2+/-2.7 months; mean body weight 6.3+/-1.6 kg) who underwent PDA closure using the Amplatzer duct occluder (ADO). The indication for using an ADO was a ductus diameter > or =2.5 or 3 mm. Device diameter selected was 1-3 mm larger than ductal diameter. The mean systolic pulmonary artery pressure was 40.9+/-18.2 mmHg. The mean Qp/Qs ratio was 3.1+/-1.2. The mean ductus diameter was 3.3+/-0.8 mm. ADO was successfully deployed in 45 patients. Failure occurred in 1 case. The mean diameter of device used was 5.4+/-1.1 mm. No severe complications occurred. At the 1-month echocardiographic follow-up, a small residual shunt was present in 4 of 45 patients and had disappeared in all 4 patients at the 3-month follow-up. One patient developed a moderate degree of left ventricular outflow tract obstruction 2.3 years after the procedure. Transcatheter closure of PDA in infants using the ADO is a safe and effective method.

Impact of mitral valve geometry on hemodynamic efficacy of surgical repair in secondary mitral regurgitation.

PubMed

Padala, Muralidhar; Gyoneva, Lazarina I; Thourani, Vinod H; Yoganathan, Ajit P

2014-01-01

Mitral valve geometry is significantly altered secondary to left ventricular remodeling in non-ischemic and ischemic dilated cardiomyopathies. Since the extent of remodeling and asymmetry of dilatation of the ventricle differ significantly between individual patients, the valve geometry and tethering also differ. The study aim was to determine if mitral valve geometry has an impact on the efficacy of surgical repairs to eliminate regurgitation and restore valve closure in a validated experimental model. Porcine mitral valves (n = 8) were studied in a pulsatile heart simulator, in which the mitral valve geometry can be precisely altered and controlled throughout the experiment. Baseline hemodynamics for each valve were measured (Control), and the valves were tethered in two distinct ways: annular dilatation with 7 mm apical papillary muscle (PM) displacement (Tether 1, symmetric), and annular dilatation with 7 mm apical, 7 mm posterior and 7 mm lateral PM displacement (Tether 2, asymmetric). Mitral annuloplasty was performed on each valve (Annular Repair), succeeded by anterior leaflet secondary chordal cutting (Sub-annular Repair). The efficacy of each repair in the setting of a given valve geometry was quantified by measuring the changes in mitral regurgitation (MR), leaflet coaptation length, tethering height and area. At baseline, none of the valves was regurgitant. Significant leaflet tethering was measured in Tether 2 over Tether 1, but both groups were significantly higher compared to baseline (60.9 +/- 31 mm2 for Control versus 129.7 +/- 28.4 mm2 for Tether 1 versus 186.4 +/- 36.3 mm2 for Tether 2). Consequently, the MR fraction was higher in Tether 2 group (23.0 +/- 5.7%) than in Tether 1 (10.5 +/- 5.5%). Mitral annuloplasty reduced MR in both groups, but remnant regurgitation after the repair was higher in Tether 2. After chordal cutting a similar trend was observed with trace regurgitation in Tether 1 group at 3.6 +/- 2.8%, in comparison to 18.6 +/- 4.2% in the Tether 2 group. In this experimental model, the tethering geometry of the mitral valve impacts the valve hemodynamics after annuloplasty and chordal cutting. The quantitative assessment of valve geometry may help in tailoring a repair to the specific tethering pattern.

Pelvic flexure enterotomy closure in the horse with a TA-90 stapling device: A retrospective clinical study of 84 cases (2001–2008)

PubMed Central

Rosser, Julie; Brounts, Sabrina; Slone, Don; Lynch, Tim; Livesey, Michael; Hughes, Faith; Clark, Carol

2012-01-01

Our objective was to compare survival and complication rates of horses undergoing pelvic flexure enterotomy closure with a TA-90 stapler to those with hand-sewn closure. Medical records of horses undergoing pelvic flexure enterotomy between 2001 and 2008 were reviewed. History, clinical signs, surgical findings, surgical techniques, and post-operative complications were recorded. Long-term outcome was established by telephone questionnaire. Of 84 pelvic flexure enterotomies performed, 70 were stapled and 14 were hand-sewn. Seventy-seven horses survived to discharge (91.7%). There were no significant associations between survival and closure technique (P = 0.69). Follow-up was available for 54 horses; 50 survived long-term (93.0%). No statistical significance was identified between long-term survival and closure method (P = 0.39). Forty horses went on to athletic performance (80.0%). TA-90 stapled closure of pelvic flexure enterotomies is a safe technique resulting in survival and complication rates equivalent to those of hand-sewn closure. PMID:23204584

Left atrial appendage closure followed by 6 weeks of antithrombotic therapy: a prospective single-center experience.

PubMed

Chun, K R Julian; Bordignon, Stefano; Urban, Verena; Perrotta, Laura; Dugo, Daniela; Fürnkranz, Alexander; Nowak, Bernd; Schmidt, Boris

2013-12-01

Currently, 2 different left atrial appendage (LAA) closure systems are available for stroke prevention in nonvalvular atrial fibrillation but comparative data are lacking. To prospectively compare procedural data and patient outcome for 2 contemporary LAA closure systems and to investigate an alternative antithrombotic treatment regimen in high-risk patients. Patients with nonvalvular atrial fibrillation, with high risk for stroke, and who either had contraindication or were not willing to accept oral anticoagulation were prospectively enrolled. Watchman (Boston Scientific, Natick, MA; group A) or Amplatzer Cardiac Plug (St Jude Medical, Minneapolis, MN; group B) devices were implanted. All patients received antithrombotic therapy for 6 weeks. After repeat transesophageal echocardiography, patients were switched to aspirin. Eighty patients were enrolled. There was no statistical difference in patient characteristics in groups A and B: CHA2DS2VASC score: 4.1 ± 1.5 versus 4.5 ± 1.8; HASBLED score: 3.1 ± 1.1 versus 3.1 ± 1.1, respectively. LAA closure was achieved in 78 of 80 patients (98%) (group A: 38 of 40 [95%] vs group B: 40 of 40 [100%]). There was no difference in procedure time (group A: 48 ± 16 minutes vs group B: 47 ± 15 minutes; P = .69) and fluoroscopy time (group A: 6.0 ± 4.7 minutes vs group B: 7.3 ± 4.4 minutes; P = .25). Major complications included 1 air embolism and delayed tamponade in each group. After 6 weeks, 1 device dislodgment and 4 device-related thrombi were detected. Ninety-four percent of the patients (73 of 77) were switched to aspirin after 6 weeks. During a median follow-up of 364 days (Q1-Q3: 283-539 days), no systemic embolism occurred, but 3 patients died (heart failure: n = 2; bleeding: n = 1). Implantation of both LAA closure devices can be performed with high success rates in high-risk patients. Postprocedural 6 weeks antithrombotic therapy followed by aspirin therapy needs to be confirmed in a larger study. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Spent fuel container alignment device and method

DOEpatents

Jones, Stewart D.; Chapek, George V.

1996-01-01

An alignment device is used with a spent fuel shipping container including a plurality of fuel pockets for spent fuel arranged in an annular array and having a rotatable cover including an access opening therein. The alignment device includes a lightweight plate which is installed over the access opening of the cover. A laser device is mounted on the plate so as to emit a laser beam through a laser admittance window in the cover into the container in the direction of a pre-established target associated with a particular fuel pocket. An indexing arrangement on the container provides an indication of the angular position of the rotatable cover when the laser beam produced by the laser is brought into alignment with the target of the associated fuel pocket.

Catheter Ablation of Atrial Fibrillation in Patients with Hardware in the Heart - Septal Closure Devices, Mechanical Valves and More.

PubMed

Bartoletti, Stefano; Santangeli, Pasquale; DI Biase, Luigi; Natale, Andrea

2013-01-01

Patients with mechanical "hardware" in the heart, such as those with mechanical cardiac valves or atrial septal closure devices, represent a population at high risk of developing AF. Catheter ablation of AF in these subjects might represent a challenge, due to the perceived higher risk of complications associated with the presence of intracardiac mechanical devices. Accordingly, such patients were excluded or poorly represented in major trials proving the benefit of catheter ablation for the rhythm-control of AF. However, recent evidence supports the concept that catheter ablation procedures might be equally effective in these patients, without a significant increase in the risk of procedural complications. This review will summarize the current state-of-the-art on catheter ablation of AF in patients with mechanical "hardware" in the heart.

Observation of a periodic array of flux-closure quadrants in strained ferroelectric PbTiO 3 films

DOE PAGES

Tang, Y. L.; Zhu, Y. L; Ma, Xiuliang; ...

2015-05-01

Nanoscale ferroelectrics are expected to exhibit various exotic domain configurations, such as the full flux-closure pattern that is well known in ferromagnetic materials. Here we observe not only the atomic morphology of the flux-closure quadrant but also a periodic array of flux closures in ferroelectric PbTiO 3 films, mediated by tensile strain on a GdScO 3 substrate. Using aberration-corrected scanning transmission electron microscopy, we directly visualize an alternating array of clockwise and counterclockwise flux closures, whose periodicity depends on the PbTiO 3 film thickness. In the vicinity of the core, the strain is sufficient to rupture the lattice, with strainmore » gradients up to 10 9 per meter. We found engineering strain at the nanoscale may facilitate the development of nanoscale ferroelectric devices.« less

Transcatheter closure of a large patent ductus arteriosus using jugular access in an infant.

PubMed

Fernandes, Precylia; Assaidi, Anass; Baruteau, Alban-Elouen; Fraisse, Alain

2018-03-01

Trans-catheter device closure of patent ductus arteriosus (PDA) via femoral route is the commonly used, safe and effective procedure. Trans-jugular approach has been successfully used in older children with interrupted inferior vena cava. We report a case of successful occlusion of PDA using Amplatzer duct occluder (ADO) via trans-jugular approach following difficulties encountered in gaining femoral venous access. A 6-month-old male infant, weighing 8 kg was admitted for percutaneous catheter closure of PDA. Echocardiogram showed a 4.5 mm duct and left heart dilatation. Femoral venous access was not possible; therefore, we decided to use a trans-jugular approach. The duct was occluded using 8/6 mm ADO. Successful closure of the duct was confirmed with an aortogram. Post procedure echocardiogram showed no residual shunt across the duct. We highlight that trans-catheter closure of PDA using jugular venous access is safe and effective even in infants.

Patent Foramen Ovale Closure or Antiplatelet Therapy for Cryptogenic Stroke.

PubMed

Søndergaard, Lars; Kasner, Scott E; Rhodes, John F; Andersen, Grethe; Iversen, Helle K; Nielsen-Kudsk, Jens E; Settergren, Magnus; Sjöstrand, Christina; Roine, Risto O; Hildick-Smith, David; Spence, J David; Thomassen, Lars

2017-09-14

The efficacy of closure of a patent foramen ovale (PFO) in the prevention of recurrent stroke after cryptogenic stroke is uncertain. We investigated the effect of PFO closure combined with antiplatelet therapy versus antiplatelet therapy alone on the risks of recurrent stroke and new brain infarctions. In this multinational trial involving patients with a PFO who had had a cryptogenic stroke, we randomly assigned patients, in a 2:1 ratio, to undergo PFO closure plus antiplatelet therapy (PFO closure group) or to receive antiplatelet therapy alone (antiplatelet-only group). Imaging of the brain was performed at the baseline screening and at 24 months. The coprimary end points were freedom from clinical evidence of ischemic stroke (reported here as the percentage of patients who had a recurrence of stroke) through at least 24 months after randomization and the 24-month incidence of new brain infarction, which was a composite of clinical ischemic stroke or silent brain infarction detected on imaging. We enrolled 664 patients (mean age, 45.2 years), of whom 81% had moderate or large interatrial shunts. During a median follow-up of 3.2 years, clinical ischemic stroke occurred in 6 of 441 patients (1.4%) in the PFO closure group and in 12 of 223 patients (5.4%) in the antiplatelet-only group (hazard ratio, 0.23; 95% confidence interval [CI], 0.09 to 0.62; P=0.002). The incidence of new brain infarctions was significantly lower in the PFO closure group than in the antiplatelet-only group (22 patients [5.7%] vs. 20 patients [11.3%]; relative risk, 0.51; 95% CI, 0.29 to 0.91; P=0.04), but the incidence of silent brain infarction did not differ significantly between the study groups (P=0.97). Serious adverse events occurred in 23.1% of the patients in the PFO closure group and in 27.8% of the patients in the antiplatelet-only group (P=0.22). Serious device-related adverse events occurred in 6 patients (1.4%) in the PFO closure group, and atrial fibrillation occurred in 29 patients (6.6%) after PFO closure. Among patients with a PFO who had had a cryptogenic stroke, the risk of subsequent ischemic stroke was lower among those assigned to PFO closure combined with antiplatelet therapy than among those assigned to antiplatelet therapy alone; however, PFO closure was associated with higher rates of device complications and atrial fibrillation. (Funded by W.L. Gore and Associates; Gore REDUCE ClinicalTrials.gov number, NCT00738894 .).

Closure of patent foramen ovale versus medical therapy after cryptogenic stroke.

PubMed

Carroll, John D; Saver, Jeffrey L; Thaler, David E; Smalling, Richard W; Berry, Scott; MacDonald, Lee A; Marks, David S; Tirschwell, David L

2013-03-21

Whether closure of a patent foramen ovale is effective in the prevention of recurrent ischemic stroke in patients who have had a cryptogenic stroke is unknown. We conducted a trial to evaluate whether closure is superior to medical therapy alone in preventing recurrent ischemic stroke or early death in patients 18 to 60 years of age. In this prospective, multicenter, randomized, event-driven trial, we randomly assigned patients, in a 1:1 ratio, to medical therapy alone or closure of the patent foramen ovale. The primary results of the trial were analyzed when the target of 25 primary end-point events had been observed and adjudicated. We enrolled 980 patients (mean age, 45.9 years) at 69 sites. The medical-therapy group received one or more antiplatelet medications (74.8%) or warfarin (25.2%). Treatment exposure between the two groups was unequal (1375 patient-years in the closure group vs. 1184 patient-years in the medical-therapy group, P=0.009) owing to a higher dropout rate in the medical-therapy group. In the intention-to-treat cohort, 9 patients in the closure group and 16 in the medical-therapy group had a recurrence of stroke (hazard ratio with closure, 0.49; 95% confidence interval [CI], 0.22 to 1.11; P=0.08). The between-group difference in the rate of recurrent stroke was significant in the prespecified per-protocol cohort (6 events in the closure group vs. 14 events in the medical-therapy group; hazard ratio, 0.37; 95% CI, 0.14 to 0.96; P=0.03) and in the as-treated cohort (5 events vs. 16 events; hazard ratio, 0.27; 95% CI, 0.10 to 0.75; P=0.007). Serious adverse events occurred in 23.0% of the patients in the closure group and in 21.6% in the medical-therapy group (P=0.65). Procedure-related or device-related serious adverse events occurred in 21 of 499 patients in the closure group (4.2%), but the rate of atrial fibrillation or device thrombus was not increased. In the primary intention-to-treat analysis, there was no significant benefit associated with closure of a patent foramen ovale in adults who had had a cryptogenic ischemic stroke. However, closure was superior to medical therapy alone in the prespecified per-protocol and as-treated analyses, with a low rate of associated risks. (Funded by St. Jude Medical; RESPECT ClinicalTrials.gov number, NCT00465270.).

Transcatheter Closure of Patent Ductus Arteriosus in Extremely Premature Newborns: Early Results and Midterm Follow-Up.

PubMed

Zahn, Evan M; Peck, Daniel; Phillips, Alistair; Nevin, Phillip; Basaker, Kaylan; Simmons, Charles; McRae, Marion E; Early, Tracy; Garg, Ruchira

2016-12-12

The goal of this study was to describe early and midterm outcomes of extremely premature newborns (EPNs) who underwent transcatheter echocardiographically guided patent ductus arteriosus (PDA) closure. Surgical ligation of PDA in EPNs confers significant risk for procedural morbidity and adverse long-term outcomes. The Amplatzer Vascular Plug II was used in all cases. Post-ligation syndrome was defined using previously published parameters. Patients were followed at pre-specified intervals, and prospectively collected data were reviewed. Transcatheter closure was attempted in 24 EPNs (mean procedural age 30 days [range 5 to 80 days], mean procedural weight 1,249 g [range 755 to 2,380 g]) and was successful in 88%. The 3 procedural failures were related to the development of left pulmonary artery (LPA) stenosis caused by the device, and all devices were removed uneventfully. Complications included 2 instances of device malposition, resolved with device repositioning, and 1 instance of LPA stenosis, requiring an LPA stent. There were no procedural deaths, cases of post-ligation syndrome, residual PDA, or device embolization. Survival to discharge was 96% (23 of 24), with a single late death unrelated to the procedure. After a median follow-up period of 11.1 months, all patients were alive and well, with no residual PDA or evidence of LPA or aortic coarctation. This newly described technique can be performed safely with a high success rate and minimal procedural morbidity in EPNs. Early and midterm follow-up is encouraging. Future efforts should be directed toward developing specific devices for this unique application. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Device for improved air and fuel distribution to a combustor

DOEpatents

Laster, Walter R.; Schilp, Reinhard

2016-05-31

A flow conditioning device (30, 50, 70, 100, 150) for a can annular gas turbine engine, including a plurality of flow elements (32, 34, 52, 54, 72, 74, 102) disposed in a compressed air flow path (42, 60, 80, 114, 122) leading to a combustor (12), configured such that relative adjustment of at least one flow directing element (32, 52, 72, 110) with respect to an adjacent flow directing element (34, 54, 74, 112, 120) during operation of the gas turbine engine is effective to adjust a level of choking of the compressed air flow path (42, 60, 80, 114, 122).

The Double-Orifice Valve Technique to Treat Tricuspid Valve Incompetence.

PubMed

Hetzer, Roland; Javier, Mariano; Delmo Walter, Eva Maria

2016-01-01

A straightforward tricuspid valve (TV) repair technique was used to treat either moderate or severe functional (normal valve with dilated annulus) or for primary/organic (Ebstein's anomaly, leaflet retraction/tethering and chordal malposition/tethering, with annular dilatation) TV incompetence, and its long-term outcome assessed. A double-orifice valve technique was employed in 91 patients (mean age 52.6 ± 23.2 years; median age 56 years; range: 0.6-82 years) with severe tricuspid regurgitation. Among the patients, three had post-transplant iatrogenic chordal rupture, five had infective endocarditis, 11 had mitral valve insufficiency, 23 had Ebstein's anomaly, and 47 had isolated severe TV incompetence. The basic principle was to reduce the distance between the coapting leaflets, wherein the most mobile leaflet could coapt to the opposite leaflet, by creating two orifices, ensuring valve competence. The TV repair was performed through a median sternotomy or right anterior thoracotomy in the fifth intercostal space under cardiopulmonary bypass. The degree and extent of creating a double-valve orifice was determined by considering the minimal body surface area (BSA)-related acceptable TV diameter. Repair was accomplished by passing pledgeted mattress sutures from the middle of the true anterior annulus to a spot on the opposite septal annulus, located approximately two-thirds of the length of the septal annulus to avoid injury to the bundle of His. The annular apposition divides the TV into a larger anterior and a smaller posterior orifices, enabling valve closure, on both sides. In adults, the diameter of the anterior valve orifice should be 23-25 mm, and the posterior orifice 15-18 mm; thus, the total valve orifice area is 5-6 cm2. In children, the total valve orifice should be a standard deviation of 1.7 mm for a BSA of <1. 0m2, and 1.5 mm for a BSA of >1.0m2. During a mean follow up of 8.7 ± 1.34 years (median 10 years; range: 1.5-25.9 years) there have been no reoperations for TV insufficiency or stenosis. Reoperations on three patients (mean age 42.5 ± 8.7 years) were indicated for aortic valve replacement at 14 months postoperatively (n = 1) and for assist device implantation (n = 2) who eventually underwent heart transplant at 18 and 20 months after TV repair, respectively. The cumulative 12-year survival rate was 86.9%. This double-orifice technique is technically a straightforward repair to abolish TV incompetence with highly satisfactory results, particularly in patients with severe annular dilatation or with leaflet and chordal tethering. In the present series, the technique provided no pitfalls (if the location of the conduction system was borne in mind), requiring only a gentle placement of sutures. It also led to no residual regurgitation or reoperation during the follow up period.

The Use of Ion Implantation for Materials Processing.

DTIC Science & Technology

1980-10-06

consists of a series of sections, each section being an annular insulator (glass) and a shaped metal electrode (polished aluminum ) cemented together. A...depending on the ion species, semiconductor material, attached materials (such as aluminum leads), implantation energy, and dose; but some devices are...concentration of subsurface carbon. Appearing directly beneath the oxide layer, the C concentration first reaches a maximum of about five times the bulk

Heat Recovery at Army Materiel Command (AMC) Facilities

DTIC Science & Technology

1988-06-01

industrial complexes and somewhat smaller commercial/ HVAC ** systems, a portion of this waste heat can be recovered, improving energy efficiency. Heat...devices are used in sequence. Other shell-and-tube applications include heat transfer from process liquids, condensates, and cooling water. Two...pipe consists of a sealed element involving an annular capillary wick con- tained inside the full length of the tube, with an appropriate entrained

A proof-of-concept study of the VeinScrew: A new percutaneous venous closure device.

PubMed

Boersma, Doeke; de Borst, Gert Jan; Moll, Frans L

2017-02-01

Objective This study evaluated the concept of percutaneous closure of insufficient veins using the VeinScrew principle. Methods The VeinScrew is designed to place a spring-shaped implant that contracts and clamps around the vein. The ability of the device to occlude adequately was tested in a bench model experiment. The feasibility of accurate placement and adequate venous occlusion was evaluated in an animal experiment and in a human cadaveric experiment. Results The VeinScrew implant occluded up to a pressure of 135 mmHg. In vivo studies confirmed that deployment was challenging but technically feasible, and subsequent phlebography showed closure of the vein. The cadaveric study showed that percutaneous placement of the evolved VeinScrew around the great saphenous vein was feasible and accurate. Conclusions The current studies show the feasibility of the VeinScrew concept. Future developments and translational studies are necessary to determine the potential of this technique as a new option in the phlebologist's toolbox.

Temporary Abdominal Closure Combined With an Irrigating System Utilizing Hypochlorous Acid Solution to Decrease Abdominal Mucopurulence

PubMed Central

Matthews, Marc R.; Quan, Asia N.; Weir, Alexandra S.; Foster, Kevin N.; Caruso, Daniel M.

2018-01-01

Introduction: Leaving the abdominal cavity open is a well-described and frequently utilized technique in the treatment of severe intra-abdominal sepsis. Irrigation through a negative pressure wound therapy device is a technique employed to assist in the closure of wounds as well as the reduction of bacterial contamination. Furthermore, hypochlorous acid has been found to be safe and effective in microorganismal elimination from extremity wounds. There is no literature regarding the infusion of hypochlorous solution into the abdominal cavity for intra-abdominal sepsis or mucopurulent abscesses or biofilm. Objectives: A 47-year-old man with granulomatosis polyangiitis was started on weekly rituximab. After 4 infusions, skin sloughing, ultimately diagnosed as toxic epidermal necrolysis, developed. During the hospital course, he developed sepsis and bowel perforation necessitating an exploratory laparotomy. The abdomen was left open with a temporary abdominal closure using the Abthera open abdomen negative wound therapy device; however, the abdomen remained infected with visually diffuse, thickening mucopurulence despite multiple washouts. Therefore, a VAC Vera-Flo irrigation device was combined with the Abthera open abdomen negative wound therapy device and cyclical irrigation of hypochlorous acid. After 72 hours, the purulence visually was improved and no adverse events were recorded with the placement of intra-abdominal hypochlorous acid. Conclusions: The combination of two medical devices for the intra-abdominal instillation of irrigation is considered “off-label use” from the manufacturer's recommendations. In addition, the repeated instillation of hypochlorous acid solution has not been described but was noted to have visually decreased the contaminated effluent within the intra-abdominal fluid. PMID:29527250

Incomplete aneurysm coverage after patent foramen ovale closure in patients with huge atrial septal aneurysm: effects on left atrial functional remodeling.

PubMed

Rigatelli, Gianluca; Ronco, Federico; Cardaioli, Paolo; Dell'avvocata, Fabio; Braggion, Gabriele; Giordan, Massimo; Aggio, Silvio

2010-08-01

Large devices are often implanted to treat patent foramen ovale (PFO) and atrial septal aneurysm (ASA) with increase risk of erosion and thrombosis. Our study is aimed to assess the impact on left atrium functional remodeling and clinical outcomes of partial coverage of the approach using moderately small Amplatzer ASD Cribriform Occluder in patients with large PFO and ASA. We prospectively enrolled 30 consecutive patients with previous stroke (mean age 36 +/- 9.5 years, 19 females), significant PFO, and large ASA referred to our center for catheter-based PFO closure. Left atrium (LA) passive and active emptying, LA conduit function, and LA ejection fraction were computed before and after 6 months from the procedure by echocardiography. The preclosure values were compared to values of a normal healthy population of sex and heart rate matched 30 patients. Preclosure values demonstrated significantly greater reservoir function as well as passive and active emptying, with significantly reduced conduit function and LA ejection fraction, when compared normal healthy subjects. All patients underwent successful transcatheter closure (25 mm device in 15 patients, 30 mm device in 6 patients, mean ratio device/diameter of the interatrial septum = 0.74). Incomplete ASA coverage in both orthogonal views was observed in 21 patients. Compared to patients with complete coverage, there were no differences in LA functional parameters and occlusion rates. This study confirmed that large ASAs are associated with LA dysfunction. The use of relatively small Amplatzer ASD Cribriform Occluder devices is probably effective enough to promote functional remodeling of the left atrium.

The open abdomen and temporary abdominal closure systems--historical evolution and systematic review.

PubMed

Quyn, A J; Johnston, C; Hall, D; Chambers, A; Arapova, N; Ogston, S; Amin, A I

2012-08-01

Several techniques for temporary abdominal closure have been developed. We systematically review the literature on temporary abdominal closure to ascertain whether the method can be tailored to the indication. Medline, Embase, the Cochrane Central Register of Controlled Trials and relevant meeting abstracts until December 2009 were searched using the following headings: open abdomen, laparostomy, VAC (vacuum assisted closure), TNP (topical negative pressure), fascial closure, temporary abdominal closure, fascial dehiscence and deep wound dehiscence. The data were analysed by closure technique and aetiology. The primary end-points included delayed fascial closure and in-hospital mortality. The secondary end-points were intra-abdominal complications. The search identified 106 papers for inclusion. The techniques described were VAC (38 series), mesh/sheet (30 series), packing (15 series), Wittmann patch (eight series), Bogotá bag (six series), dynamic retention sutures (three series), zipper (15 series), skin only and locking device (one series each). The highest facial closure rates were seen with the Wittmann patch (78%), dynamic retention sutures (71%) and VAC (61%). Temporary abdominal closure has evolved from simple packing to VAC based systems. In the absence of sepsis Wittmann patch and VAC offered the best outcome. In its presence VAC had the highest delayed primary closure and the lowest mortality rates. However, due to data heterogeneity only limited conclusions can be drawn from this analysis. © 2012 The Authors. Colorectal Disease © 2012 The Association of Coloproctology of Great Britain and Ireland.

Split ring floating air riding seal for a turbine

DOEpatents

Mills, Jacob A

2015-11-03

A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, and a central passage connecting the annular cavity to the annular piston chamber to supply compressed air to the seal face, where the annular piston assembly is a split piston assembly to maintain a tight seal as coning of the rotor disk occurs.

Successful transcatheter occlusion of an anomalous pulmonary vein with dual drainage to the left atrium.

PubMed

Wilson, W; Horlick, E; Benson, L

2015-06-01

We describe a case of a scimitar syndrome "variant" where dual drainage existed from the right upper and middle pulmonary veins to the inferior vena cava and left atrium. Device closure of the anomalous vein at the level of the connection to the IVC was successful in achieving diversion of pulmonary venous flow to the left atrium. Vigilance during work-up of anomalous pulmonary venous drainage (whether isolated or associated with other cardiac defects that may be amenable to device closure) is important to define the presence of dual connections to the left atrium, in which case a less-invasive transcatheter approach may be feasible. © 2015 Wiley Periodicals, Inc.

A novel technique for transcatheter patent ductus arteriosus closure in extremely preterm infants using commercially available technology.

PubMed

Zahn, Evan M; Nevin, Phillip; Simmons, Charles; Garg, Ruchira

2015-02-01

To describe a new technique for transcatheter patent ductus arteriosus (PDA) closure in extremely preterm infants using commercially available technology. PDA in premature neonates continues to be a significant clinical problem contributing importantly to both morbidity and mortality. Surgical ligation and medical therapy both have their drawbacks. Hospital records and catheterization reports of all premature neonates (< 32 weeks gestation) who underwent transcatheter PDA closure between March 2013 and February 2014 were reviewed. Particular attention was paid to procedural details, complications, and short and mid-term outcomes. Six premature infants born at gestational ages ranging between 26 and 31 weeks (median, 26 weeks) underwent attempted transcatheter PDA closure using the Amplatzer Vascular Plug II (AVP II). Median age and weight was 21.5 days (16-80 days) and 1,180 g (870-2,240 g), respectively. Fluoroscopy and echocardiography were used to guide device. Contrast angiography was not used in any patient. Complete closure was achieved in all patients with no major procedural complications. Median fluoroscopy and procedural times were 9.4 (0-19.5) and 51.5 (33-87) min, respectively. All patients were alive at the time of this report. There were no instances of device migration, left pulmonary artery (LPA), or aortic coarctation. This preliminary study demonstrates that transcatheter PDA closure can be successfully performed in extremely preterm neonates using currently available technology with a high success rate and a low incidence of complications. This report also describes a novel transvenous approach using a combination of echocardiography and judicious use of fluoroscopy to avoid arterial access in this fragile patient population. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

Catheter Closure Through a Venous Approach of Patent Ductus Arteriosus in Small Pediatric Patients Using Combined Angiographic and Echocardiographic Guidance.

PubMed

Thanopoulos, Basil Vasilios D; Ninios, Vlassis; Dardas, Petros; Giannopoulos, Andreas; Deleanou, Dan; Iancovici, Silvia

2016-11-15

The standard technique of catheter closure of patent ductus arteriosus (PDA) may be associated with arterial complications particularly in small pediatric patients. The aim of this study was to evaluate whether catheter closure of PDA in small children using an exclusive venous approach is a safe and effective alternative to closure with the standard technique. One hundred-twelve patients, aged 2 to 24 months, were randomly assigned in a 1:1 ratio to catheter closure of PDA using the standard technique (group 1) and an exclusive venous approach (group 2), respectively. In group 2, the procedure was guided using hand injections of contrast media through the delivery sheath and 2-dimensional and color Doppler echocardiography. Group 1: the PDA diameter ranged from 2 to 5.5 mm and the device diameter ranged from 4 to 8 mm. The PDA occluders were permanently implanted in all patients. Five losses of the arterial pulses that were restored with intravenous infusion of heparin and recombinant tissue plasminogen activator (rtPA), and 4 groin hematomas were the main complications of the procedure. Group 2: the mean PDA diameter ranged from 2.5 to 6 mm and the device diameter ranged from 3 to 8 mm. The PDA occluders were permanently implanted in all but 2 patients. There were no complications. Complete echocardiographic closure of PDA at 1-month follow-up was observed in all 110 patients. Exclusive transvenous PDA occlusion is an effective and safe technique that prevents the arterial complications of the standard approach in small children. Copyright © 2016 Elsevier Inc. All rights reserved.

Patent ductus arteriosus closure using Occlutech® Duct Occluder, experience in Port Elizabeth, South Africa

PubMed Central

Pepeta, Lungile; Greyling, Adele; Nxele, Mahlubandile Fintan; Makrexeni, Zongezile Masonwabe

2017-01-01

Background: Percutaneous closure of patent ductus arteriosus (PDA) has become standard therapy. Experience with the Occlutech® Duct Occluder is limited. Methods: Data regarding ductal closure using Occlutech® Duct Occluder were reviewed and prospectively collected. Demographics, hemodynamic and angiographic characteristics, complications, and outcomes were documented. Results: From March 2013 to June 2016, 65 patients (43 females and 22 males) underwent percutaneous closure of the PDA using Occlutech® Duct Occluder. The median age of the patients was 11 months (range, 1–454 months) and the median weight was 8.5 kg (range 2.5–78 kg). The mean pulmonary artery median pressure was 27 mmHg (range, 12–100 mmHg) and the QP: Qs ratio median was 1.8 (range, 1–7.5), with a pulmonary vascular resistance mean of 2.7 WU (standard deviation [SD] ±2.1). Thirty-two patients had Krichenko Type A duct (49%); 7, Type C (11%); 4, Type D (6%); and 22, Type E (34%). The ductal size (narrowest diameter at the pulmonic end) mean was 3.5 mm (SD ± 1.9 mm). The screening time mean was 17.3 min (SD ± 11.6). Out of 63 patients with successful closure of the PDA using Occlutech® Duct Occluder, there were 15 patients with small PDAs; 25 with moderate PDAs, and 23 with large PDAs. In one patient, the device dislodged to the descending aorta, and in two patients, to the right pulmonary artery immediately following deployment, with successful percutaneous (two) and surgical (one) retrieval. Complete ductal occlusion was achieved in all 63 patients on day one. Conclusion: The Occlutech® Duct Occluder is a safe and effective device for closure of ducts in appropriately selected patients. PMID:28566820

Patent ductus arteriosus closure using Occlutech® Duct Occluder, experience in Port Elizabeth, South Africa.

PubMed

Pepeta, Lungile; Greyling, Adele; Nxele, Mahlubandile Fintan; Makrexeni, Zongezile Masonwabe

2017-01-01

Percutaneous closure of patent ductus arteriosus (PDA) has become standard therapy. Experience with the Occlutech® Duct Occluder is limited. Data regarding ductal closure using Occlutech® Duct Occluder were reviewed and prospectively collected. Demographics, hemodynamic and angiographic characteristics, complications, and outcomes were documented. From March 2013 to June 2016, 65 patients (43 females and 22 males) underwent percutaneous closure of the PDA using Occlutech® Duct Occluder. The median age of the patients was 11 months (range, 1-454 months) and the median weight was 8.5 kg (range 2.5-78 kg). The mean pulmonary artery median pressure was 27 mmHg (range, 12-100 mmHg) and the QP: Qs ratio median was 1.8 (range, 1-7.5), with a pulmonary vascular resistance mean of 2.7 WU (standard deviation [SD] ±2.1). Thirty-two patients had Krichenko Type A duct (49%); 7, Type C (11%); 4, Type D (6%); and 22, Type E (34%). The ductal size (narrowest diameter at the pulmonic end) mean was 3.5 mm (SD ± 1.9 mm). The screening time mean was 17.3 min (SD ± 11.6). Out of 63 patients with successful closure of the PDA using Occlutech® Duct Occluder, there were 15 patients with small PDAs; 25 with moderate PDAs, and 23 with large PDAs. In one patient, the device dislodged to the descending aorta, and in two patients, to the right pulmonary artery immediately following deployment, with successful percutaneous (two) and surgical (one) retrieval. Complete ductal occlusion was achieved in all 63 patients on day one. The Occlutech® Duct Occluder is a safe and effective device for closure of ducts in appropriately selected patients.

Heat-transfer characteristics of the R113 annular two-phase closed thermosyphon - Heat transfer in the condenser

NASA Astrophysics Data System (ADS)

Maezawa, Saburo; Tsuchida, Akira; Takuma, Masao

1988-08-01

Visual observation of flow patterns in the condenser and heat transfer measurements were conducted for heat transfer rate ranges of 18-800 W using a vertical annular device with various quantities of R113 as a working fluid. As a result of visual observations, it was shown that ripples (interfacial waves) were generated on the condensate film surface when the condensate film Reynolds number exceeded approximately 20, and the condensation heat transfer was prompted. A simple theoretical analysis was presented in which the effects of interfacial waves and vapor drag were both considered. This analysis agreed very well with experimental results when the working fluid quantity was small enough so that the two-phase mixture generated by boiling the working fluid did not reach the condenser. The effects of interfacial waves and vapor drag on condensation heat transfer were also investigated theoretically.

High Power Microwave Emission of Large and Small Orbit Gyrotron Devices in Rectangular Interaction Structures

NASA Astrophysics Data System (ADS)

Hochman, J. M.; Gilgenbach, R. M.; Jaynes, R. L.; Rintamaki, J. I.; Luginsland, J. W.; Lau, Y. Y.; Spencer, T. A.

1996-11-01

Experiments utilize large and small orbit e-beam gyrotron devices in a rectangular-cross-section (RCS) gyrotron. This device is being explored to examine polarization control. Other research issues include pulse shortening, and mode competition. MELBA generates electron beams with parameters of: -800kV, 1-10kA diode current, and 0.5-1.0 μ sec pulselengths. The small orbit gyrotron device is converted to a large orbit experiment by running MELBA's annular electron beam through a magnetic cusp. Initial experiments showed an increase in beam alpha (V_perp/V_par) of a factor of ~ 4 between small and large orbit devices. Experimental results from the RCS gyrotron will be compared for large-orbit and small-orbit electron beams. Beam transport data and frequency measurements will be presented. Computer modeling utilizing the MAGIC and E-gun codes will be shown.

Magnetic core mounting system

DOEpatents

Ronning, Jeffrey J.

2002-01-01

A mounting apparatus for an electromagnetic device such as a transformer of inductor includes a generally planar metallic plate as a first heat sink, and a metallic mounting cup as a second heat sink. The mounting cup includes a cavity configured to receive the electromagnetic device, the cavity being defined by a base, and an axially-extending annular sidewall extending from the base to a flange portion of the mounting cup. The mounting cup includes first and second passages for allowing the leads of first and second windings of the electromagnetic device to be routed out of the cavity. The cavity is filled with a polyurethane potting resin, and the mounting cup, including the potted electromagnetic device, is mounted to the plate heat sink using fasteners. The mounting cup, which surrounds the electromagnetic device, in combination with the potting resin provides improved thermal transfer to the plate heat sink, as well as providing resistance to vibration and shocks.

Ceramic gas turbine shroud

DOEpatents

Shi, Jun; Green, Kevin E.

2014-07-22

An example gas turbine engine shroud includes a first annular ceramic wall having an inner side for resisting high temperature turbine engine gasses and an outer side with a plurality of radial slots. A second annular metallic wall is positioned radially outwardly of and enclosing the first annular ceramic wall and has a plurality of tabs in communication with the slot of the first annular ceramic wall. The tabs of the second annular metallic wall and slots of the first annular ceramic wall are in communication such that the first annular ceramic wall and second annular metallic wall are affixed.

Floating air riding seal for a turbine

DOEpatents

Ebert, Todd A

2016-08-16

A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber formed in the stator, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, where the axial moveable annular piston includes an inlet scoop on a side opposite to the annular cavity that scoops up the swirling cooling air and directs the cooling air to the annular cavity to form an air cushion with the seal surface of the rotor.

A blinded, prospective, randomized controlled trial of topical negative pressure wound closure in India.

PubMed

Mody, Gita N; Nirmal, Ida Anita; Duraisamy, Sulochana; Perakath, Benjamin

2008-12-01

Wound closure using topical negative pressure (TNP) has been reported to be effective, but equipment costs can be prohibitive in resource-challenged countries. Because nonhealing wounds are exceedingly common in developing countries such as India, the ability to optimize wound care with limited resources is very important. To investigate the feasibility and efficacy of providing TNP in an Indian medical referral center, a randomized controlled trial comparing a locally constructed TNP device (treatment) to wet-to-dry gauze dressings (control) was conducted. Eligible study participants (N = 48) were recruited from the inpatient wards. Wound etiologies included diabetic foot ulcers (15), pressure ulcers (11), cellulitis/fasciitis (11), and "other" (11). Following enrollment, wound size was assessed using computer-aided measurements of digital photographs and block-randomized to the study arms using a concealed allocation table. Wounds in both treatment groups were débrided before dressing application and patients were followed until wound closure or being lost to follow-up for an average of 26.3 days (+/- 18.5) in the control and 33.1 days (+/- 37.3) in the treatment group. No statistically significant differences in time to closure between the two treatment groups were observed except in a subset analysis of pressure ulcers (mean 10 +/- 7.11 days for treatment and 27 +/- 10.6 days in control group, P = 0.05). Direct costs to close a pressure ulcer also were lower in the TNP than in the control group. A review of the literature suggests the outcomes obtained using a locally constructed TNP device are similar to those obtained using commercially available devices. As a result of this study, a dedicated tissue viability team has been established to identify wounds suitable for TNP, oversee treatment, monitor the need for surgical débridement, and employ wound healing principles and technology appropriately. These results suggest that inexpensive materials can be utilized for TNP wound closure in a developing country.

Modelling and Control of an Annular Momentum Control Device

NASA Technical Reports Server (NTRS)

Downer, James R.; Johnson, Bruce G.

1988-01-01

The results of a modelling and control study for an advanced momentum storage device supported on magnetic bearings are documented. The control challenge posed by this device lies in its dynamics being such a strong function of flywheel rotational speed. At high rotational speed, this can lead to open loop instabilities, resulting in requirements for minimum and maximum control bandwidths and gains for the stabilizing controllers. Using recently developed analysis tools for systems described by complex coefficient differential equations, the closed properties of the controllers were analyzed and stability properties established. Various feedback controllers are investigated and discussed. Both translational and angular dynamics compensators are developed, and measures of system stability and robustness to plant and operational speed variations are presented.

ION MAGNETRON

DOEpatents

Gow, J.D.; Layman, R.W.

1962-10-31

A magnetohydrodynamic device or plasma generator of the ion magnetron class is described wherein a long central electrode is disposed along the axis of an evacuated cylinder. A radial electric field and an axial magnetic field are provided between the cylsnder and the electrode, forming a plasma trapping and heating region. For maximum effectiveness, neutral particles from the cylinder wall must be prevented from entering such region This is effected by forming a cylindrical sheath of electrons near the cylinder wall for ionizing undesired neutral particles, which are then trapped and removed by the magnetic field. An annular filament at one end of the device provides the electrons, which follow the axial magnetic field to a reflecting electrode at the opposite end of the device. (AEC)

Statistical assessment of normal mitral annular geometry using automated three-dimensional echocardiographic analysis.

PubMed

Pouch, Alison M; Vergnat, Mathieu; McGarvey, Jeremy R; Ferrari, Giovanni; Jackson, Benjamin M; Sehgal, Chandra M; Yushkevich, Paul A; Gorman, Robert C; Gorman, Joseph H

2014-01-01

The basis of mitral annuloplasty ring design has progressed from qualitative surgical intuition to experimental and theoretical analysis of annular geometry with quantitative imaging techniques. In this work, we present an automated three-dimensional (3D) echocardiographic image analysis method that can be used to statistically assess variability in normal mitral annular geometry to support advancement in annuloplasty ring design. Three-dimensional patient-specific models of the mitral annulus were automatically generated from 3D echocardiographic images acquired from subjects with normal mitral valve structure and function. Geometric annular measurements including annular circumference, annular height, septolateral diameter, intercommissural width, and the annular height to intercommissural width ratio were automatically calculated. A mean 3D annular contour was computed, and principal component analysis was used to evaluate variability in normal annular shape. The following mean ± standard deviations were obtained from 3D echocardiographic image analysis: annular circumference, 107.0 ± 14.6 mm; annular height, 7.6 ± 2.8 mm; septolateral diameter, 28.5 ± 3.7 mm; intercommissural width, 33.0 ± 5.3 mm; and annular height to intercommissural width ratio, 22.7% ± 6.9%. Principal component analysis indicated that shape variability was primarily related to overall annular size, with more subtle variation in the skewness and height of the anterior annular peak, independent of annular diameter. Patient-specific 3D echocardiographic-based modeling of the human mitral valve enables statistical analysis of physiologically normal mitral annular geometry. The tool can potentially lead to the development of a new generation of annuloplasty rings that restore the diseased mitral valve annulus back to a truly normal geometry. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Apparatus and method for pressure testing closure disks

DOEpatents

Merten, Jr., Charles W.

1992-01-21

A method and device for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A tensile load is transmitted by a piston in combination with fluid pressure to the hollow notched plug.

On the feasibility of the computational modelling of the endoluminal vacuum-assisted closure of an oesophageal anastomotic leakage

PubMed Central

Bellomo, Facundo J.; Rosales, Iván; del Castillo, Luis F.; Sánchez, Ricardo; Turon, Pau

2018-01-01

Endoluminal vacuum-assisted closure (E-VAC) is a promising therapy to treat anastomotic leakages of the oesophagus and bowel which are associated with high morbidity and mortality rates. An open-pore polyurethane foam is introduced into the leakage cavity and connected to a device that applies a suction pressure to accelerate the closure of the defect. Computational analysis of this healing process can advance our understanding of the biomechanical mechanisms at play. To this aim, we use a dual-stage finite-element analysis in which (i) the structural problem addresses the cavity reduction caused by the suction and (ii) a new constitutive formulation models tissue healing via permanent deformations coupled to a stiffness increase. The numerical implementation in an in-house code is described and a qualitative example illustrates the basic characteristics of the model. The computational model successfully reproduces the generic closure of an anastomotic leakage cavity, supporting the hypothesis that suction pressure promotes healing by means of the aforementioned mechanisms. However, the current framework needs to be enriched with empirical data to help advance device designs and treatment guidelines. Nonetheless, this conceptual study confirms that computational analysis can reproduce E-VAC of anastomotic leakages and establishes the bases for better understanding the mechanobiology of anastomotic defect healing. PMID:29515846

Morphologic Characteristics and Relating Factors to the Need of Technical Modification in Transcatheter Closure of Large Atrial Septal Defect (≥25 mm)

PubMed Central

Park, Su-Jin; Kim, Nam Kyun; Kim, Jung Ok; Yoo, Byung Won; Sul, Jun Hee

2010-01-01

Background and Objectives The rigid coupling between the delivery wire and the right atrial disk has been occasionally encountered during transcatheter closure of atrial septal defect (ASD). Therefore the device frequently makes a perpendicular angle, and the leading edge of left atrial disk slips through the defect and prolapses into right atrium (RA) before it is properly placed in the septum. The purpose of this study is to investigate relating factors to the need of technical modification in transcatheter closure of large ASD and to evaluate relevant morphologic characteristics of atrial septal rim in this situation. Subjects and Methods From July, 2003 to May, 2007, 312 patients underwent transcatheter occlusion of ASD with Amplatzer Septal Occluder® (ASO, AGA medical corporation, Golden Valley, MN, USA) at Yonsei Cardiovascular Center and among them 109 patients had large ASD (≥25 mm) and these patients were enrolled in our study. Patients were divided into two groups according to the deploying methods of the device (Group I: standard method, Group II: modified methods). Assessments of the defects and its surrounding rims were made by echocardiography. Results There were no differences between 2 groups in age, body weight and height except for balloon-stretched diameter (stop-flow technique) and device size. Group II patients with modified methods showed larger balloon-stretched diameter and device size than group I patients with standard method. The mean length of anterosuperior (AS) rim in group II was significantly shorter than group I (p<0.05). As the size of the device used in procedure increased, there was a trend towards increase in the need of modified methods. Conclusion This study shows that AS rim deficiency and the size of ASD may be the relating factors to the need of technical modification in transcatheter closure of ASD. Therefore, when the initial try with standard method is not successful in large ASD with deficient AS rim, we suggest that changing strategy of implantation may save time and efforts and possibly reduce the risk of complications associated with prolonged procedure. PMID:20421960

Transcatheter occlusion of the patent ductus arteriosus in premature infants weighing less than 1200 g.

PubMed

Morville, Patrice; Douchin, Stephanie; Bouvaist, Helene; Dauphin, Claire

2018-05-01

Over the last few decades different strategies have been proposed to treat persistent ductal patency in premature infants. The advent of the Amplatzer Duct Occluder II Additional Size (ADOIIAS) provided the potential to close the patent ductus arteriosus (PDA). Opinions differ on the significance and treatment of PDA in premature neonates. Because surgical ligation and medical therapy both have their drawbacks, interventional catheterisation can be considered as an alternative means of closing the ductus arteriosus. Our aim was to analyse the feasibility, safety and efficacy of this device in premature infants weighing <1200 g at procedure. Eighteen premature infants underwent transcatheter closure. The procedure was performed in the catheterisation laboratory by venous cannulation without angiography. The position of the occluder was directed by X-ray and ultrasound. We looked at procedural details, device size selection, complications and short-term and mid-term outcomes. Eighteen infants born at gestational ages ranging between 23.6 and 29+6 weeks (mean±SD 25+6±3 weeks) underwent transcatheter PDA closure. Their mean age and weight at the time of the procedure was 20 days (range 8-44 days) and 980 g (range 680-1200 g), respectively. The mean PDA and device waist diameters were 3.2±0.6 mm (range 2.2-4 mm) and 4.5±0.6 mm, respectively, and the mean PDA and device lengths were 4.3±1.2 mm (range 2-10 mm) and 2.5±0.9 mm, respectively. Complete closure was achieved in all but one patient. There was no device migration. One patient developed a left pulmonary artery obstruction. Three infants died. Two deaths were related to complications of prematurity and one to the procedure. Transcatheter closure of a PDA is feasible in very low weight infants with ADOIIAS and is an alternative to surgery. Success requires perfect selection and placement of the occluder. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Obesity: An Independent Risk Factor for Insufficient Hemostasis Using the AngioSeal Vascular Closure Device After Antegrade Puncture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minko, Peter, E-mail: peterminko@yahoo.com; Katoh, Marcus; Graeber, Stefan

Purpose: This study was designed to investigate the efficacy of the AngioSeal vascular closure device after antegrade puncture of the femoral artery. Methods: In a prospective study, 120 consecutive patients underwent lower limb vascular intervention by an antegrade access to the common femoral artery (CFA). After intervention, a 6F (n = 88) or an 8F (n = 32) AngioSeal vascular closure device was used to achieve hemostasis. The technical success or the cause of failure was documented. In addition, the coagulation status (platelets, INR, prothrombin time, atrial thromboplastin time (PTT)), hypertonus, locoregional habitus of the groin, body mass index (BMI),more » presence of calcifications, and history of previous surgical interventions of the CFA were evaluated. Results: Hemostasis was achieved in 97 patients (81%). In 12 patients (10%), persistent bleeding of the puncture site required manual compression. In another nine patients (8%) a kink of the sheath obviated the passage of the collagen plug toward the vessel, and in two patients the anchor dislodged out of the vessel, requiring manual compression. There were no significant differences between the groups of successful and unsuccessful sealing regarding the mean platelets (241 vs. 254 * 10{sup 9}/l; P = 0.86), INR (1.06 vs. 1.02; P = 0.52), prothrombin time (90% vs. 90%; P = 0.86), and PTT (30 vs. 31 s; P = 0.82). However, unsuccessful sealing was more likely in obese patients with an increased BMI (26.6 vs. 28.8 kg/m{sup 2}; P = 0.04). Conclusions: Obesity seems to be an independent risk factor for insufficient sealing using the AngioSeal vascular closure device after antegrade puncture of the CFA. In 8% of our patients, hemostasis could not be achieved due to kink of the flexible sheath.« less

The off-label use of the Amplatzer muscular VSD occluder for large patent ductus arteriosus: a case report and review.

PubMed

Cubeddu, Roberto J; Babin, Ivan; Inglessis, Ignacio

2014-07-01

A percutaneous approach to the closure of patent ductus arteriosus (PDA) is the preferred procedure in the majority of cases. However, there is little experience with percutaneous closure of unusually large PDA. We report the case of a 28-year-old female with moderate left ventricular dilation and pulmonary hypertension resulting from a large 16 mm PDA. Percutaneous closure was successfully performed using an off-label Amplatzer muscular ventricular septal defect occluder after intravascular ultrasound assessment. Technical challenges, including accurate assessment of defect size and device selection are exemplified along with a comprehensive overview of the available literature.

Is transcatheter closure better than medical therapy for cryptogenic stroke with patent foramen ovale? A meta-analysis of randomised trials.

PubMed

Nagaraja, Vinayak; Raval, Jwalant; Eslick, Guy D; Burgess, David; Denniss, A Robert

2013-11-01

The prevalence of patent foramen ovale among patients with cryptogenic stroke is higher than that in the general population. Closure with a percutaneous device is often recommended in such patients, but it is not known whether this intervention reduces the risk of recurrent stroke. A systematic search was conducted using MEDLINE, PubMed, EMBASE, Current Contents Connect, Cochrane library, Google Scholar, Science Direct, and Web of Science. Original data were abstracted from each study and used to calculate a pooled event rate (ER), odd ratio (OR) and 95% confidence interval (95% CI). Only three randomised trials comprising 2303 patients met full criteria for analysis. Procedural success (ER: 94.20%, 95% CI: 87.6-97.4%) and effective closure (ER: 92.70%, 95% CI: 85.9-96.4%) of closure therapy were good. The odds ratio for stroke (OR: 0.654, 95% CI: 0.358-1.193) and transient ischaemic attack (OR: 0.768, 95% CI: 0.413-1.429) did not confer a benefit of PFO closure over medical therapy. Age {<45 years (OR: 0.449, 95% CI: 0.117-1.722), >45 years (OR: 0.707, 95% CI: 0.27-1.856)}, gender {males (OR: 0.498, 95% CI: 0.247-1.004), females (OR: 1.16, 95% CI: 0.597-2.255)}, substantial shunt size (OR: 0.354, 95% CI: 0.089-1.406) and the presence of atrial septal aneurysm (OR: 0.7, 95% CI: 0.21-2.33) did not influence the treatment effect of PFO closure. However, the adverse events like major vascular complication (OR: 10.905, 95% CI: 1.997-59.562) and atrial fibrillation (OR: 3.297, 95% CI: 0.874-12.432) were significantly higher in the closure group. In patients with cryptogenic stroke or TIA who had a patent foramen ovale, closure with a device does not confer an advantage over medical therapy and is associated with adverse events like major vascular complication and atrial fibrillation. Copyright © 2013 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). All rights reserved.

21 CFR 878.4011 - Tissue adhesive with adjunct wound closure device for topical approximation of skin.

Code of Federal Regulations, 2011 CFR

2011-04-01

... ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY... approximated skin edges of wounds from surgical incisions, including punctures from minimally invasive surgery, and simple, thoroughly cleansed, trauma-induced lacerations. It may be used in conjunction with, but...

The Aeroacoustics and Aerodynamics of High-Speed Coanda Devices, Part 2: Effects of Modifications for Flow Control and Noise Reduction

NASA Astrophysics Data System (ADS)

Carpenter, P. W.; Smith, C.

1997-12-01

The paper describes two studies of the effects of flow control devices on the aerodynamics and aeroacoustics of a high-speed Coanda flow that is formed when a supersonic jet issues from a radial nozzle and adheres to a tulip-shaped body of revolution. Shadowgraphy and other flow-visualization techniques are used to reveal the various features of the complex flow fields. The acoustic characteristics are obtained from far- and near-field measurements with an array of microphones in an anechoic chamber. First the effects of incorporating a step between the annular exit slot and the Coanda surface are investigated. The step is incorporated to ensure that the breakaway pressure is raised to a level well above the maximum operating pressure. It substantially increases the complexity of the flow field and acoustic characteristics. In particular, it promotes the generation of two groups of discrete tones. A theoretical model based on a self-generated feedback loop is proposed to explain how these tones are generated. The second study investigates the effects of replacing the annular exit slot with a saw-toothed one with the aim of eliminating the discrete tones and thereby substantially reducing the level of noise generated.

Fast-Acting Valve

NASA Technical Reports Server (NTRS)

Wojciechowski, Bogdan V. (Inventor); Pegg, Robert J. (Inventor)

2003-01-01

A fast-acting valve includes an annular valve seat that defines an annular valve orifice between the edges of the annular valve seat, an annular valve plug sized to cover the valve orifice when the valve is closed, and a valve-plug holder for moving the annular valve plug on and off the annular valve seat. The use of an annular orifice reduces the characteristic distance between the edges of the valve seat. Rather than this distance being equal to the diameter of the orifice, as it is for a conventional circular orifice, the characteristic distance equals the distance between the inner and outer radii (for a circular annulus). The reduced characteristic distance greatly reduces the gap required between the annular valve plug and the annular valve seat for the valve to be fully open, thereby greatly reducing the required stroke and corresponding speed and acceleration of the annular valve plug. The use of a valve-plug holder that is under independent control to move the annular valve plug between its open and closed positions is important for achieving controllable fast operation of the valve.

System for controlling apnea

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holzrichter, John F

2015-05-05

An implanted stimulation device or air control device are activated by an external radar-like sensor for controlling apnea. The radar-like sensor senses the closure of the air flow cavity, and associated control circuitry signals (1) a stimulator to cause muscles to open the air passage way that is closing or closed or (2) an air control device to open the air passage way that is closing or closed.

Preclinical assessment of a modified Occlutech left atrial appendage closure device in a canine model.

PubMed

Kim, Jung-Sun; Lee, Seul-Gee; Bong, Sung-Kyung; Park, Se-Il; Hong, Sung-Yu; Shin, Sanghoon; Shim, Chi Young; Hong, Geu-Ru; Choi, Donghoon; Jang, Yangsoo; Park, Jai-Wun

2016-10-15

LAA occlusion has a similar stroke prevention efficacy compared to anticoagulation treatment for non-valvular atrial fibrillation. The objective of this study was to assess the feasibility and safety of a modified Occlutech® left atrial appendage (LAA) closure device in a canine model. The device was implanted in 10 dogs (33±1kg) using fluoroscopy and transesophageal echocardiography (TEE) guidance. The modified Occlutech® LAA occlusion device was compared with the current version, the Watchman device, and the Amplazter cardiac plug (ACP). LAA occlusion and anchoring to the LAA were evaluated. All dogs were assessed using angiography, TEE, and a gross anatomy examination. The 10 LAA occlusion devices were to be implanted into 10 dogs (5 modified Occlutech devices, 3 current version of Occlutech devices, 1 Watchman, and 1 ACP). LAA implantation was not performed in one dog due to transeptal puncture failure. The three current version of Occlutech devices were embolized immediately after implantation, so three modified devices of the same size were implanted securely without embolization. The mean implant size was 20.1±2.0mm. The devices chosen were a mean of 23.3±10.6% larger than the measured landing zone diameters. Post-implant angiography and TEE revealed well-positioned devices without pericardial effusion or impingement on surrounding structures. The results of this acute animal study suggested that a modified Occlutech® LAA occlusion device was feasible and had greater anchoring performance in canines. Additional large clinical studies are needed to evaluate safety and efficacy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

APPARATUS FOR CATALYTICALLY COMBINING GASES

DOEpatents

Busey, H.M.

1958-08-12

A convection type recombiner is described for catalytically recombining hydrogen and oxygen which have been radiolytically decomposed in an aqueous homogeneous nuclear reactor. The device is so designed that the energy of recombination is used to circulate the gas mixture over the catalyst. The device consists of a vertical cylinder having baffles at its lower enda above these coarse screens having platinum and alumina pellets cemented thereon, and an annular passage for the return of recombined, condensed water to the reactor moderator system. This devicea having no moving parts, provides a simple and efficient means of removing the danger of accumulated hot radioactive, explosive gases, and restoring them to the moderator system for reuse.

Concomitant transcatheter aortic valve and left ventricular assist device implantation.

PubMed

Baum, Christina; Seiffert, Moritz; Treede, Hendrik; Reichenspurner, Hermann; Deuse, Tobias

2013-01-01

Relevant aortic regurgitation (AR) requires surgical repair at the time of left ventricular assist device (LVAD) implantation to reduce recirculation and ensure adequate forward flow. We report here on a patient with moderate AR in a noncalcified aortic valve and extensive calcification of the ascending aorta. The latter precluded aortic-crossclamping and, thus, surgical intervention on the aortic valve. Although there were no valvular or annular calcifications, a JenaValve transcatheter heart valve was successfully placed transapically with subsequent LVAD implantation in one operation. We believe concomitant transcatheter aortic valve implantation (TAVI) and LVAD implantation is a promising hybrid procedure, even in patients with pure AR.

Impact of Implantable Transvenous Device Lead Location on Severity of Tricuspid Regurgitation

PubMed Central

Addetia, Karima; Maffessanti, Francesco; Mediratta, Anuj; Yamat, Megan; Weinert, Lynn; Moss, Joshua D.; Nayak, Hemal M.; Burke, Martin C.; Patel, Amit R.; Kruse, Eric; Jeevanandam, Valluvan; Mor-Avi, Victor; Lang, Roberto M.

2015-01-01

Background Implantable device leads can cause tricuspid regurgitation (TR) when they interfere with leaflet motion. The aim of this study was to determine whether lead-leaflet interference is associated with TR severity, independent of other causative factors of functional TR. Methods A total of 100 patients who underwent transthoracic two-dimensional and three-dimensional (3D) echocardiography of the tricuspid valve before and after lead placement were studied. Lead position was classified on 3D echocardiography as leaflet-interfering or noninterfering. TR severity was estimated by vena contracta (VC) width. Logistic regression analysis was used to identify factors associated with postdevice TR, including predevice VC width, right ventricular end-diastolic and end-systolic areas, fractional area change, right atrial size, tricuspid annular diameter, TR gradient, device lead age, and presence or absence of lead interference. Odds ratios were used to describe the association with moderate (VC width ≥ 0.5 cm) or severe (VC width ≥ 0.7 cm) TR, separately, using bivariate and stepwise multivariate logistic regression analysis. Results Forty-five of 100 patients showed device lead tricuspid valve leaflet interference. The septal leaflet was the most commonly affected (23 patients). On bivariate analysis, preimplantation VC width, right atrial size, tricuspid annular diameter, and lead-leaflet interference were significantly associated with postdevice TR. On multivariate analysis, preimplantation VC width and the presence of an interfering lead were independently associated with postdevice TR. Furthermore, the presence of an interfering lead was the only factor associated with TR worsening, increasing the likelihood of developing moderate or severe TR by 15- and 11-fold, respectively. Conclusion Lead-leaflet interference as seen on 3D echocardiography is associated with TR after device lead placement, suggesting that 3D echocardiography should be used to assess for lead interference in patients with significant TR. PMID:25129393

Use of cryopoor plasma for albumin replacement and continuous antimicrobial infusion for treatment of septic peritonitis in a dog.

PubMed

Ropski, Meaghan K; Guillaumin, Julien; Monnig, Andrea A; Townsend, Katy; McLoughlin, Mary A

2017-05-01

To report the successful management of a dog with septic peritonitis and septic shock secondary to enterectomy dehiscence using novel techniques for identification of intestinal dehiscence and for septic shock treatment. A 5-year-old castrated male Bernese Mountain Dog presented for lethargy 6 days following enterotomy for foreign body obstruction. Septic peritonitis was identified due to dehiscence of the enterotomy site, and resection and anastomosis were performed using a gastrointestinal anastomosis and thoracoabdominal stapling device. Postoperatively the patient experienced severe hypotension, which responded to norepinephrine constant rate infusion (CRI) after failing to improve with fluid therapy or dopamine CRI. Further treatment included antimicrobial CRI and supportive care including careful fluid therapy. Due to low effective circulating volume paired with intersititial fluid overload and large volume abdominal effusion, fluid therapy consisted of a combination of human serum albumin, canine albumin, synthetic colloids, and isotonic crystalloids. Cryopoor plasma (CPP) was used as a source of canine albumin and intravascular volume. On Day 4, food dye was given through a nasogastric tube due to suspicion of dehiscence of the anastomosis site. Dehiscence was confirmed during abdominal exploratory, and a second resection and anastomosis was performed. Abdominal partial closure with vacuum-assisted closure device was performed. Supportive care was continued with CPP CRI and imipenem CRI. Planned relaparotomy to change the vacuum-assisted closure device was performed 48 hours later, with abdominal closure 96 hours after anastomosis. The patient was discharged on Day 15. Recheck 12 months later was normal. This case includes novel techniques such food dye via nasogastric tube to identify anastomosis dehiscence, use of CPP as a source of canine albumin, and antimicrobial CRI in a dog with septic peritonitis. © Veterinary Emergency and Critical Care Society 2017.

Endoscopic repair of an injured internal carotid artery utilizing femoral endovascular closure devices.

PubMed

Van Rompaey, Jason; Bowers, Greg; Radhakrishnan, Jay; Panizza, Benedict; Solares, C Arturo

2014-06-01

Injury to the internal carotid artery is a feared complication of endoscopic endonasal surgery of the skull base. Such an event, although rare, is associated with high morbidity and mortality. Even if bleeding is controlled, permanent neurological defects frequently persist. Many techniques have been developed to manage internal carotid artery rupture with varying degrees of success. The purpose of this study was to explore endoscopic management of arterial damage with endovascular closure devices used for a femoral arteriotomy. The ability to remotely suture a damaged artery permits the possible adaptation of this technology in managing endoscopic arterial complications. Technical note. After the creation of an endoscopic endonasal corridor in a cadaveric specimen, an arteriotomy was created at the cavernous portion of the internal carotid artery. The Angio-Seal, StarClose, and MynxGrip vascular closure devices were utilized under endoscopic guidance to repair the arteriotomy. Angiography was then done on a cadaver sutured with the StarClose. Both the Angio-Seal and StarClose were deployed quickly and appeared to provide sufficient closure of the arteriotomy. The Angio-Seal required the use of a guidewire and was longer to deploy when compared with the StarClose. The StarClose deployment was quick and facile. The MynxGrip also deployed without difficulty. The Angio-Seal and StarClose systems were both successfully deployed utilizing an endoscopic endonasal approach. The MynxGrip was the easiest to deploy and has the greatest potential to be of benefit in this application. Further studies with hemodynamic models are required to properly assess the appropriateness in this setting. NA. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Longitudinal evaluation of P-wave dispersion and P-wave maximum in children after transcatheter device closure of secundum atrial septal defect.

PubMed

Grignani, Robert Teodoro; Tolentino, Kim Martin; Rajgor, Dimple Dayaram; Quek, Swee Chye

2015-06-01

Transcatheter device closure of the secundum atrial septal defect (ASD) in children prevents atrial arrhythmias in older age. However, the benefits of favourable atrial electrocardiographic markers in these children remain elusive. We aimed to review the electrocardiographic markers of atrial activity in a longitudinal fashion. We retrospectively reviewed longitudinal data of all children who underwent transcatheter device closure at the National University Hospital between 2004 and 2013. The inclusion criteria included the presence of a secundum-type ASD with left to right shunt and evidence of increased right ventricular volume load (Q p/Q s ratio >1.5 and/or right ventricular dilatation). A total of 25 patients with a mean follow-up of 44.7 ± 33.47 (7.3-117.4) months were included. P maximum and P dispersion decreased at 2 months, P amplitude at 1 week and remained so until last follow-up. A positive trend was seen with a correlation coefficient of +0.12 for P maximum, +0.08 for P dispersion and 0.34 for P amplitude. There was a higher baseline P amplitude and P dispersion in patients who were older than 10 years and a non-significant trend to support an increase in both P maximum (71.0 ± 8.8 vs. 73.2 ± 12.7), P dispersion (17.0 ± 6.5 vs. 22.0 ± 11.3) and P amplitude (0.88 ± 0.25 vs. 1.02 ± 0.23) in patients with an ASD more than 15 mm compared with an ASD <15 mm. There is reduction in both P maximum and P dispersion as early as 2 months, which persisted on follow-up. Earlier closure may result in more favourable electrocardiographic results.

Triple acting radial seal

DOEpatents

Ebert, Todd A [West Palm Beach, FL; Carella, John A [Jupiter, FL

2012-03-13

A triple acting radial seal used as an interstage seal assembly in a gas turbine engine, where the seal assembly includes an interstage seal support extending from a stationary inner shroud of a vane ring, the interstage seal support includes a larger annular radial inward facing groove in which an outer annular floating seal assembly is secured for radial displacement, and the outer annular floating seal assembly includes a smaller annular radial inward facing groove in which an inner annular floating seal assembly is secured also for radial displacement. A compliant seal is secured to the inner annular floating seal assembly. The outer annular floating seal assembly encapsulates the inner annular floating seal assembly which is made from a very low alpha material in order to reduce thermal stress.

Improved Electrical Contact For Dowhhole Drilling Networks

DOEpatents

Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron

2005-08-16

An electrical contact system for transmitting information across tool joints while minimizing signal reflections that occur at the tool joints includes a first electrical contact comprising an annular resilient material. An annular conductor is embedded within the annular resilient material and has a surface exposed from the annular resilient material. A second electrical contact is provided that is substantially equal to the first electrical contact. Likewise, the second electrical contact has an annular resilient material and an annular conductor. The two electrical contacts configured to contact one another such that the annular conductors of each come into physical contact. The annular resilient materials of each electrical contact each have dielectric characteristics and dimensions that are adjusted to provide desired impedance to the electrical contacts.

Real-time 3D transesophageal echocardiography-guided closure of a complicated patent ductus arteriosus in a dog.

PubMed

Doocy, K R; Nelson, D A; Saunders, A B

2017-06-01

Advanced imaging modalities are becoming more widely available in veterinary cardiology, including the use of transesophageal echocardiography (TEE) during occlusion of patent ductus arteriosus (PDA) in dogs. The dog in this report had a complex history of attempted ligation and a large PDA that initially precluded device placement thereby limiting the options for PDA closure. Following a second thoracotomy and partial ligation, the morphology of the PDA was altered and device occlusion was an option. Angiographic assessment of the PDA was limited by the presence of hemoclips, and the direction of ductal flow related to the change in anatomy following ligature placement. Intra-operative TEE, in particular real-time three-dimensional imaging, was pivotal for assessing the PDA morphology, monitoring during the procedure, selecting the device size, and confirming device placement. The TEE images increased operator confidence that the size and location of the device were appropriate before release despite the unusual position. This report highlights the benefit of intra-operative TEE, in particular real-time three-dimensional imaging, for successful PDA occlusion in a complicated case. Copyright © 2017 Elsevier B.V. All rights reserved.

Efficacy of a novel procedure sheath and closure device during diagnostic catheterization: the multicenter randomized clinical trial of the FISH device.

PubMed

Bavry, Anthony A; Raymond, Russell E; Bhatt, Deepak L; Chambers, Charles E; DeNardo, Andrew J; Hermiller, James B; Myers, Paul R; Pitts, Douglas E; Scott, John A; Savader, Scott J; Steinhubl, Steven

2008-04-01

The aim of vascular closure devices is to safely secure the arterial access site at the conclusion of catheterization procedures, thereby increasing patient comfort and decreasing time to hemostasis and ambulation. The FISH (femoral introducer sheath and hemostasis) device is novel in that the access sheath and closure component are incorporated onto the same system. The FISH pivotal investigation was conducted at 8 catheterization laboratories throughout the United States. Eligible diagnostic patients were randomized (2 to 1) to the FISH device versus manual compression and assessed for time to hemostasis and time to ambulation. Half of the participants underwent ultrasonographic evaluation at 30-day follow up. Enrollment for an interventional cohort is ongoing and will be reported at a later date; however, the interventional patients enrolled to date were combined with the diagnostic patients to comprise the safety data of the trial. Overall, 191 patients were randomized to the FISH device and 106 patients to manual compression. Most patients received a 6 Fr sheath (approximately 70%), while the remaining patients received a 5 or 8 Fr sheath. Twenty-seven patients who received the FISH device were converted to manual compression due to anticipated suboptimal hemostasis. Among the diagnostic patients, the mean time to hemostasis was 8.9 minutes for the FISH device, compared to 17.2 minutes for manual compression (p < 0.0001). Similarly, the mean time to ambulation was 2.4 hours for the FISH device, compared to 4.3 hours for manual compression (p < 0.0001). Among the total cohort, there was 1 death and 1 episode of major access-site-related bleeding that required transfusion occurred in the FISH group (1.1%), compared to no serious adverse safety events in the manual compression group (p = 1.0). For the FISH group, there were 5 minor adverse safety events; 3 access-site hematomas and 2 pseudoaneurysms treated with thrombin injection, and in the manual compression group, there was 2 access-site hematomas and 1 pseudoaneurysm treated with thrombin injection (p = 1.0). Among diagnostic patients with good sheath placement and favorable femoral anatomy, the FISH device is superior in achieving time to hemostasis and ambulation compared to manual compression. At 30 days, there is no apparent difference in serious or minor adverse vascular events with the use of the FISH device.

CHARGE BOTTLE FOR A MASS SEPARATOR

DOEpatents

Davidson, P.H.

1959-07-01

Improved mass separator charge bottles are described for containing a dense charge of a chemical compound of copper, nickel, lead or other useful substance which is to be vaporized, and to the method of utilizing such improvcd charge bottles so that the chemical compound is vaporized from the under surface of the charge and thus permits the non-volatile portion thereof to fall to the bottom of the charge bottle where it does not form an obstacle to further evaporation. The charge bottle comprises a vertically disposed cylindrical portion, an inner re-entrant cylindrical portion extending axially and downwardly into the same from the upper end thereof, and evaporative source material in the form of a chemical compound compacted within the upper annular pontion of the charge bottle formed by the re-entrant cylindrical portion, whereby vapor from the chemical compound will pass outwardly from the charge bottle through an apertured closure.

Percutaneous closure of patent foramen ovale in patients with presumed paradoxical embolism: periprocedural results and midterm risk of recurrent neurologic events.

PubMed

Balbi, Manrico; Casalino, Laura; Gnecco, Giovanni; Bezante, Gian Paolo; Pongiglione, Giacomo; Marasini, Maurizio; Del Sette, Massimo; Barsotti, Antonio

2008-08-01

To report our data on selected patients with previous paradoxical embolism who underwent transcatheter patent foramen ovale (PFO) closure. Between July 2001 and July 2007, percutaneous PFO closure was performed on 128 patients (65 women, mean age: 46 +/- 12.8 years). Patent foramen ovale closure was recommended for secondary prevention in patients with previous transient ischemic attacks (52.5%), stroke (46%), or peripheral embolism (1.5%). Implantation was successful in all patients, and at the end of intervention, complete PFO closure was achieved in 70.3% of them. There were no "major" complications (ie, deaths, device embolization or thrombosis, need for cardiac surgery). The overall incidence of complications (mostly hemorrhagic) was 7%. The mean follow-up period was 32 months. Complete closure had been achieved in 78.4% and in 82.5% of patients at the third month of transesophageal echocardiography examination and at the sixth month of transcranial Doppler examination, respectively. There were no recurrent thromboembolic events during the follow-up period. Percutaneous closure of PFO is a feasible procedure, but it is not a risk-free technique. However, in correctly selected patients (ie, large PFO and those at risk for neurologic relapse), nearly complete PFO closure seems to provide protection from future neurologic ischaemic events at midterm follow-up.

A reliable and safe gastrotomy closure technique assessed in a porcine survival model pilot study: success of the Queen's closure.

PubMed

Hookey, L C; Bielawska, B; Samis, A; Jalink, D; Ellis, R; Khokhotva, V; Hurlbut, D; Mercer, D

2009-06-01

The evolution of NOTES to clinical implementation has been hampered by lack of a reliable, safe, and easy-to-implement technique for closure of the opening created in accessing the peritoneum. The Queen's closure uses a combination of endoscopic clips and loop devices to seal such defects in the stomach wall. This study aimed to assess the Queen's closure in a porcine survival model. Five 30-kg pigs underwent endoscopic transgastric surgery with exploration of the peritoneum. The endoscope was then withdrawn back into the stomach and the closure performed. The animals were recovered, monitored closely, and underwent endoscopy 1 week after surgery. They were then euthanized at 2 (n = 2) and 3 (n = 3) weeks after surgery with subsequent necropsy. The mean procedure time (from intubation of the esophagus to withdrawal of the endoscope) was 79 minutes (range 45-105 minutes) with a mean time of exploration of the peritoneum of 14 minutes (range 8-25 minutes). All animals recovered well with no apparent pain, distress, or signs of infection. Endoscopic examination 1 week after surgery revealed all the closures to be intact and only identifiable by a small ulcer. At necropsy, the gastrotomy site was identifiable only by minor serosal adhesions. Histological study demonstrated full-thickness closure with minimal inflammation. The Queen's closure is a reliable and safe technique that provides full-thickness gastrotomy closure without any observed complications. The technique has proven to be transferable knowledge that holds promise for clinical implementation.

New laser soldering-based closures: a promising method in natural orifice transluminal endoscopic surgery.

PubMed

Bogni, Serge; Ortner, Maria-Anna; Vajtai, Istvan; Jost, Christian; Reinert, Michael; Dallemagne, Bernard; Frenz, Martin

2012-07-01

Complete closure of gastrotomy is the linchpin of safe natural orifice transgastric endoscopic surgery. To evaluate feasibility and efficacy of a new method of gastrotomy closure by using a sutureless laser tissue-soldering (LTS) technique in an ex vivo porcine stomach. In vitro experiment. Experimental laboratory. Histological analysis and internal and external liquid pressure with and without hydrochloric acid exposure were determined comparing gastrotomy closure with LTS and with hand-sewn surgical sutures. Comparison of LTS and hand-sewn surgical gastrotomy closure. The primary outcome parameter was the internal leak pressure. Secondary parameters were the difference between internal and external leak pressures, the impact of an acid environment on the device, histological changes, and feasibility of endoscopic placement. The internal liquid leak pressure after LTS was almost twice as high as after hand-sewn surgical closure (416 ± 53 mm Hg vs 229 ± 99 mm Hg; P = .01). The internal leak pressure (416 ± 53 mm Hg) after LTS was higher than the external leak pressure (154 ± 46 mm Hg; P < .0001). An acidic environment did not affect leak pressure after LTS. Endoscopic LTS closure was feasible in all experiments. Histopathology revealed only slight alterations beneath the soldering plug. In vitro experiments. Leak pressure after LTS closure of gastrotomy is higher than after hand-sewn surgical closure. LTS is a promising technique for closure of gastrotomies and iatrogenic perforations. Further experiments, in particular survival studies, are mandatory. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

To close or not to close: contemporary indications for patent foramen ovale closure.

PubMed

Zier, Lucas S; Sievert, Horst; Mahadevan, Vaikom S

2016-11-01

Patent foramen ovale (PFO) is a common congenital cardiac abnormality and that has been associated with several disease processes including transient ischemic attacks (TIA), stroke, migraine headaches with aura, decompression sickness, platypnea-orthodeoxia syndrome, and shunt induced cyanosis. Controversy exists regarding closure of PFO as a therapeutic treatment modality for these disease processes. This review addresses the contemporary clinical indications for PFO closure. Areas covered: We conducted a comprehensive literature search of contemporary research studies focusing on randomized trials and meta-analyses comparing medical therapy and device closure of PFOs for the treatment of PFO associated clinical syndromes. We synthesized this literature into a review addressing indications for PFO closure in stroke, TIA, migraine headaches with aura, decompression sickness, platypnea-orthodeoxia syndrome, and shunt induced cyanosis. Expert commentary: Because in many PFO associated conditions it can be difficult to determine the degree to which the PFO is a causative factor in the disease process, we recommend a comprehensive diagnostic evaluation to exclude other obvious etiologies of PFO associated conditions before implicating the PFO and proceeding with closure. However in the properly selected patient population there is growing clinical experience and experimental evidence suggesting that closure of PFO is a safe and effective treatment modality.

A tandem mirror plasma source for hybrid plume plasma studies

NASA Technical Reports Server (NTRS)

Yang, T. F.; Chang, F. R.; Miller, R. H.; Wenzel, K. W.; Krueger, W. A.

1985-01-01

A tandem mirror device to be considered as a hot plasma source for the hybrid plume rocket concept is discussed. The hot plamsa from this device is injected into an exhaust duct, which will interact with an annular hypersonic layer of neutral gas. The device can be used to study the dynamics of the hybrid plume, and to verify the numerical predictions obtained with computer codes. The basic system design is also geared towards low weight and compactness, and high power density at the exhaust. The basic structure of the device consists of four major subsystems: (1) an electric power supply; (2) a low temperature, high density plasma gun, such as a stream gun, an MPD source or gas cell; (3) a power booster in the form of a tandem mirror machine; and (4) an exhaust nozzle arrangement. The configuration of the tandem mirror section is shown.

Multi-Megawatt Space Nuclear Power Generation

DTIC Science & Technology

1993-06-28

electric generation, both for open- and closed-cycle opera- tion. These reactors use the particulate fuel of the type developed for HTGR reactors. What...commercial HTGR power reactors, the particles are held in place and directly cooled. Figure 2.7 shows the two types of fuel particles developed for...of MW(e), for pulsed energy devices. The FBR would use HTGR -type particle fuel , contained in a annular bed be- tween two porous frits. Helium would

Translation Studies on an Annular Field Reversed Configuration Device

DTIC Science & Technology

2012-10-01

maturity, but have all shown that a plasmoid can be ejected with significant velocity. Most of the thrusters have 1 a unique drawback , however. In some [11...operation were not possible due to interaction of the ballistic pendulum with background gases, imperfect reflections, and other complications. Steady...energy efficiency. The drawback to larger inner coil diameters is that it increases the chance of wall contact with the plasma since finite thickness

Cost comparison of transcatheter and operative closures of ostium secundum atrial septal defects

PubMed Central

O’Byrne, Michael L.; Gillespie, Matthew J.; Shinohara, Russell T.; Dori, Yoav; Rome, Jonathan J.; Glatz, Andrew C.

2015-01-01

Background Clinical outcomes for transcatheter and operative closures of atrial septal defects (ASDs) are similar. Economic cost for each method has not been well described. Methods A single-center retrospective cohort study of children and adults <30 years of age undergoing closure for single secundum ASD from January 1, 2007, to April 1, 2012, was performed to measure differences in inflation-adjusted cost of operative and transcatheter closures of ASD. A propensity score weight-adjusted multivariate regression model was used in an intention-to-treat analysis. Costs for reintervention and crossover admissions were included in primary analysis. Results A total of 244 subjects were included in the study (64% transcatheter and 36% operative), of which 2% (n = 5) were ≥18 years. Crossover rate from transcatheter to operative group was 3%. Risk of reintervention (P = .66) and 30-day mortality (P = .37) were not significantly different. In a multivariate model, adjusted cost of operative closure was 2012 US $60,992 versus 2012 US $55,841 for transcatheter closure (P < .001). Components of total cost favoring transcatheter closure were length of stay, medications, and follow-up radiologic and laboratory testing, overcoming higher costs of procedure and echocardiography. Professional costs did not differ. The rate of 30-day readmission was greater in the operative cohort, further increasing the cost advantage of transcatheter closure. Sensitivity analyses demonstrated that costs of follow-up visits influenced relative cost but that device closure remained favorable over a broad range of crossover and reintervention rates. Conclusion For single secundum ASD, cost comparison analysis favors transcatheter closure over the short term. The cost of follow-up regimens influences the cost advantage of transcatheter closure. PMID:25965721

Comparing the Tolerability of a Novel Wound Closure Device Using a Porcine Wound Model

PubMed Central

Townsend, Katy L.; Akeroyd, Jen; Russell, Duncan S.; Kruzic, Jamie J.; Robertson, Bria L.; Lear, William

2018-01-01

Objective: To compare the tolerability and mechanical tensile strength of acute skin wounds closed with nylon suture plus a novel suture bridge device (SBD) with acute skin wounds closed with nylon suture in a porcine model. Approach: Four Yucatan pigs each received 12 4.5 cm full-thickness incisions that were closed with 1 of 4 options: Suture bridge with nylon, suture bridge with nylon and subdermal polyglactin, nylon simple interrupted, and nylon simple interrupted with subdermal polyglactin. Epithelial reaction, inflammation, and scarring were examined histologically at days 10 and 42. Wound strength was examined mechanically at days 10 and 42 on ex vivo wounds from euthanized pigs. Results: Histopathology in the suture entry/exit planes showed greater dermal inflammation with a simple interrupted nylon suture retained for 42 days compared with the SBD retained for 42 days (p < 0.03). While tensile wound strength in the device and suture groups were similar at day 10, wounds closed with the devices were nearly 8 times stronger at day 42 compared with day 10 (p < 0.001). Innovation: A novel SBD optimized for cutaneous wound closure that protects the skin surface from suture strands, forms a protective bridge over the healing wound edges, and knotlessly clamps sutures. Conclusion: This study suggests that the use of a SBD increases the tolerability of nylon sutures in porcine acute skin wound closures allowing for prolonged mechanical support of the wound. For slow healing wounds, this may prevent skin wound disruption, such as edge necrosis and dehiscence. PMID:29892494

Reversal of severe mitral regurgitation by device closure of a large patent ductus arteriosus in a premature infant.

PubMed

Kheiwa, Ahmed; Ross, Robert D; Kobayashi, Daisuke

2017-01-01

We report a critically ill premature infant with severe mitral valve regurgitation associated with pulmonary hypertension and a severely dilated left atrium from a large patent ductus arteriosus. The mitral valve regurgitation improved significantly with normalisation of left atrial size 4 weeks after percutaneous closure of the patent ductus arteriosus. This case highlights the potential reversibility of severe mitral valve regurgitation with treatment of an underlying cardiac shunt.

Method and apparatus for active tamper indicating device using optical time-domain reflectometry

DOEpatents

Smith, D. Barton; Muhs, Jeffrey D.; Pickett, Chris A.; Earl, D. Duncan

1999-01-01

An optical time-domain reflectometer (OTDR) launches pulses of light into a link or a system of multiplexed links and records the waveform of pulses reflected by the seals in the link(s). If a seal is opened, the link of cables will become a discontinuous transmitter of the light pulses and the OTDR can immediately detect that a seal has been opened. By analyzing the waveform, the OTDR can also quickly determine which seal(s) were opened. In this way the invention functions as a system of active seals. The invention is intended for applications that require long-term surveillance of a large number of closures. It provides immediate tamper detection, allows for periodic access to secured closures, and can be configured for many different distributions of closures. It can monitor closures in indoor and outdoor locations and it can monitor containers or groups of containers located many kilometers apart.

CT based 3D printing is superior to transesophageal echocardiography for pre-procedure planning in left atrial appendage device closure.

PubMed

Obasare, Edinrin; Mainigi, Sumeet K; Morris, D Lynn; Slipczuk, Leandro; Goykhman, Igor; Friend, Evan; Ziccardi, Mary Rodriguez; Pressman, Gregg S

2018-05-01

Accurate assessment of the left atrial appendage (LAA) is important for pre-procedure planning when utilizing device closure for stroke reduction. Sizing is traditionally done with transesophageal echocardiography (TEE) but this is not always precise. Three-dimensional (3D) printing of the LAA may be more accurate. 24 patients underwent Watchman device (WD) implantation (71 ± 11 years, 42% female). All had complete 2-dimensional TEE. Fourteen also had cardiac computed tomography (CCT) with 3D printing to produce a latex model of the LAA for pre-procedure planning. Device implantation was unsuccessful in 2 cases (one with and one without a 3D model). The model correlated perfectly with implanted device size (R 2  = 1; p < 0.001), while TEE-predicted size showed inferior correlation (R 2  = 0.34; 95% CI 0.23-0.98, p = 0.03). Fisher's exact test showed the model better predicted final WD size than TEE (100 vs. 60%, p = 0.02). Use of the model was associated with reduced procedure time (70 ± 20 vs. 107 ± 53 min, p = 0.03), anesthesia time (134 ± 31 vs. 182 ± 61 min, p = 0.03), and fluoroscopy time (11 ± 4 vs. 20 ± 13 min, p = 0.02). Absence of peri-device leak was also more likely when the model was used (92 vs. 56%, p = 0.04). There were trends towards reduced trans-septal puncture to catheter removal time (50 ± 20 vs. 73 ± 36 min, p = 0.07), number of device deployments (1.3 ± 0.5 vs. 2.0 ± 1.2, p = 0.08), and number of devices used (1.3 ± 0.5 vs. 1.9 ± 0.9, p = 0.07). Patient specific models of the LAA improve precision in closure device sizing. Use of the printed model allowed rapid and intuitive location of the best landing zone for the device.

No evidence that manual closure of the bronchial stump has a lower failure rate than mechanical stapler closure following anatomical lung resection.

PubMed

Zakkar, Mustafa; Kanagasabay, Robin; Hunt, Ian

2014-04-01

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether manual closure of the bronchial stump is safer with lower failure rates than mechanical closure using a stapling device following anatomical lung resection. One hundred and twenty-nine papers were identified using the search below. Eight papers presented the best evidence to answer the clinical question as they included sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates and operation time were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. When looking at manual vs mechanical staples, it was noted that stapler failure can occur in around 4% of cases. The rate of bronchopleural fistula (BPF) development varied more in patients who underwent manual closure (1.5-12.5%) than in patients who underwent mechanical closure (1-5.7%). Although most of the studies reviewed showed no statistical differences between manual and mechanical closure in terms of BPF development, one study, however, showed that manual closure was significantly associated with lower numbers of postoperative BPF, while another study showed that mechanical closure is significantly associated with lower incidence of BPF. When looking at the role of the learning curve and training opportunities, it seems that the surgeon's inexperience when using mechanical staples can contribute to BPF development. A surgeon's experience can play a major role in the prevention of BPF development in patients having manual closure. Manual closure can provide a cheap and reliable technique when compared with costs incurred from using staplers, it is applicable in all situations and can be taught to surgeons in training with an acceptable risk. However, there is a lack of evidence to suggest that manual closure is better than mechanical stapler closure following anatomical lung resection.

Air riding seal for a turbine

DOEpatents

Mills, Jacob A; Brown, Wesley D; Sexton, Thomas D; Jones, Russell B

2016-07-19

An air riding seal between a rotor and a stator in a turbine of a gas turbine engine, where an annular piston is movable in an axial direction within a housing that extends from the stator, and a bellows is secured to the annular piston to form a flexible air passageway from a compressed air inlet through the annular piston and into a cushion cavity that forms an air riding seal between the annular piston and the rotor sealing surface. In another embodiment, a flexible seal secured to and extending from the annular piston forms a sealing surface between the annular piston chamber and the annular piston to provide a seal and allow for axial movement.

Ringlight for use in high radiation

DOEpatents

Baylor, G.A.; Jacket, H.S.

1992-09-01

A ringlight having an annular array of light-emitting elements centered about a viewing passage has an outer annular body with an inner annular body fitted concentrically within the outer body to form an annular void and a light-emitting aperture therebetween. A plurality of optical fibers extends into the void with end portions of the optical fibers secured therein to form an annular array at the light-emitting aperture. The first and second annular bodies cooperate to angle the end portions of the optical fibers towards a central axis of the viewing passage. 3 figs.

Orthodontic treatment of a complex open-bite malocclusion with temporary anchorage devices: a case report.

PubMed

Waldman, Alexander B

2010-08-01

Orthodontic temporary anchorage devices provide a novel alternative to orthognathic surgery for the treatment of severe anterior open-bite malocclusions. These implantable devices provide skeletal anchorage for maxillary molar intrusion, allowing for mandibular autorotation and subsequent open-bite closure. This case demonstrates step-by-step treatment of a 41-year-old woman with a severe open-bite malocclusion. Detailed orthodontic mechanics are described at every stage of treatment.

Direct imaging of the tricuspid valve annular motions by fiberoptic cardioscopy in dogs. I. Does De Vega's annuloplasty preserve the annular motions?

PubMed

Minato, N; Itoh, T

1992-12-01

Applying the technology of direct imaging by fiberoptic cardioscopy, physiologic and pathophysiologic motions of the tricuspid valve anulus were studied in 10 anesthetized normal dogs (control group) and in 9 dogs that had chronic tricuspid regurgitation (TR group). The heart was perfused with transparent modified Tyrode's solution by working heart method, and the anuli, outlined by sutured beads, were observed and recorded on a high-speed video system in real time. Tricuspid valve annular area was calculated at 14 points during the cardiac cycle. The control group was studied in the normal condition, and the tricuspid regurgitation group was studied during four interventions: nontricuspid annuloplasty group and three tricuspid annuloplasty groups with reducing tricuspid valve annular area to 80%, 65%, and 50% of that of the non-tricuspid annuloplasty group by De Vega's procedure. Tricuspid valve annular area in the control group increased by 7% during atrial systole and was reduced by 34% mainly during ventricular systole, in which the free wall annular area and the septal annular area narrowed by an equal 34%. Chronic tricuspid regurgitation lessened tricuspid valve annular area narrowing to 20% in percent reduction (p < 0.01). In the TR group the decrease in tricuspid valve annular area narrowing was attributed mainly to lessened narrowing of the free wall anulus (percent reduction of tricuspid valve annular area, 19%; p < 0.01). The amplitudes in tricuspid valve annular area narrowing were unchanged in the tricuspid annuloplasty groups even when tricuspid valve annular area, was reduced to 50% by De Vega's tricuspid annuloplasty (percent reduction of tricuspid valve annular area, 16%; not significant). These findings suggest that De Vega's tricuspid annuloplasty is a reasonable method that does preserve the physiologic annular motions in the opening and closing mechanism of the tricuspid valve.

Sealing Apparatus For Exclusion of Water From Underwater Gun Barrels.

DTIC Science & Technology

1996-03-03

4,821,441. For example, U.S. Patent No. 44,631 discloses a 11 submarine shot conductor having an India- rubber valve mounted on 12 the open end of the...11 ... barrel of the device is closed by a closure device made by a 12 material which may be perforated by the projectile disposed 13 inside the

High power coaxial ubitron

NASA Astrophysics Data System (ADS)

Balkcum, Adam J.

In the ubitron, also known as the free electron laser, high power coherent radiation is generated from the interaction of an undulating electron beam with an electromagnetic signal and a static periodic magnetic wiggler field. These devices have experimentally produced high power spanning the microwave to x-ray regimes. Potential applications range from microwave radar to the study of solid state material properties. In this dissertation, the efficient production of high power microwaves (HPM) is investigated for a ubitron employing a coaxial circuit and wiggler. Designs for the particular applications of an advanced high gradient linear accelerator driver and a directed energy source are presented. The coaxial ubitron is inherently suited for the production of HPM. It utilizes an annular electron beam to drive the low loss, RF breakdown resistant TE01 mode of a large coaxial circuit. The device's large cross-sectional area greatly reduces RF wall heat loading and the current density loading at the cathode required to produce the moderate energy (500 keV) but high current (1-10 kA) annular electron beam. Focusing and wiggling of the beam is achieved using coaxial annular periodic permanent magnet (PPM) stacks without a solenoidal guide magnetic field. This wiggler configuration is compact, efficient and can propagate the multi-kiloampere electron beams required for many HPM applications. The coaxial PPM ubitron in a traveling wave amplifier, cavity oscillator and klystron configuration is investigated using linear theory and simulation codes. A condition for the dc electron beam stability in the coaxial wiggler is derived and verified using the 2-1/2 dimensional particle-in-cell code, MAGIC. New linear theories for the cavity start-oscillation current and gain in a klystron are derived. A self-consistent nonlinear theory for the ubitron-TWT and a new nonlinear theory for the ubitron oscillator are presented. These form the basis for simulation codes which, along with MAGIC, are used to design a representative 200 MW, 40% efficient, X-band amplifier for linear accelerators and a 1 GW, 21% efficient, S-band oscillator for directed energy. The technique of axial mode profiling in the ubitron cavity oscillator is also proposed and shown to increase the simulated interaction efficiency to 46%. These devices are realizable and their experimental implementation, including electron beam formation and spurious mode suppression techniques, is discussed.

Effects of supplemental vibrational force on space closure, treatment duration, and occlusal outcome: A multicenter randomized clinical trial.

PubMed

DiBiase, Andrew T; Woodhouse, Neil R; Papageorgiou, Spyridon N; Johnson, Nicola; Slipper, Carmel; Grant, James; Alsaleh, Maryam; Khaja, Yousef; Cobourne, Martyn T

2018-04-01

A multicenter parallel 3-arm randomized clinical trial was carried out in 3 university hospitals in the United Kingdom to investigate the effect of supplemental vibratory force on space closure and treatment outcome with fixed appliances. Eighty-one subjects less than 20 years of age with mandibular incisor irregularity undergoing extraction-based fixed appliance treatment were randomly allocated to supplementary (20 minutes/day) use of an intraoral vibrational device (AcceleDent; OrthoAccel Technologies, Houston, Tex) (n = 29), an identical nonfunctional (sham) device (n = 25), or fixed-appliance only (n = 27). Space closure in the mandibular arch was measured from dental study casts taken at the start of space closure, at the next appointment, and at completion of space closure. Final records were taken at completion of treatment. Data were analyzed blindly on a per-protocol basis with descriptive statistics, 1-way analysis of variance, and linear regression modeling with 95% confidence intervals. Sixty-one subjects remained in the trial at start of space closure, with all 3 groups comparable for baseline characteristics. The overall median rate of initial mandibular arch space closure (primary outcome) was 0.89 mm per month with no difference for either the AcceleDent group (difference, -0.09 mm/month; 95% CI, -0.39 to 0.22 mm/month; P = 0.57) or the sham group (difference, -0.02 mm/month; 95% CI, -0.32 to 0.29 mm/month; P = 0.91) compared with the fixed only group. Similarly, no significant differences were identified between groups for secondary outcomes, including overall treatment duration (median, 18.6 months; P >0.05), number of visits (median, 12; P >0.05), and percentage of improvement in the Peer Assessment Rating (median, 90.0%; P >0.05). Supplemental vibratory force during orthodontic treatment with fixed appliances does not affect space closure, treatment duration, total number of visits, or final occlusal outcome. NCT02314975. The protocol was not published before trial commencement. AcceleDent units were donated by OrthoAccel Technologies; no contribution to the conduct or the writing of this study was made by the manufacturer. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Study of the interfacial reactions between a bioactive apatite-mullite glass-ceramic coating and titanium substrates using high angle annular dark field transmission electron microscopy.

PubMed

Stanton, Kenneth T; O'Flynn, Kevin P; Nakahara, Shohei; Vanhumbeeck, Jean-François; Delucca, John M; Hooghan, Bobby

2009-04-01

Glass of generic composition SiO(2) . Al(2)O(3) . P(2)O(5) . CaO . CaF(2) will crystallise predominantly to apatite and mullite upon heat-treatment. Such ceramics are bioactive, osseoconductive, and have a high resistance to fracture. As a result, they are under investigation for use as biomedical device coatings, and in particular for orthopaedic implants. Previous work has shown that the material can be successfully enamelled to titanium with an interfacial reaction zone produced during heat treatment. The present study uses high angle annular dark field transmission electron microscopy (HAADF-TEM) to conduct a detailed examination of this region. Results show evidence of complex interfacial reactions following the diffusion of titanium into an intermediate layer and the production of titanium silicides and titanium phosphides. These results confirm previously hypothesised mechanisms for the bonding of silicate bioceramics with titanium alloys.

REACTOR CONTROL

DOEpatents

Ruano, W.J.

1957-12-10

This patent relates to nuclear reactors of the type which utilize elongited rod type fuel elements immersed in a liquid moderator and shows a design whereby control of the chain reaction is obtained by varying the amount of moderator or reflector material. A central tank for containing liquid moderator and fuel elements immersed therein is disposed within a surrounding outer tank providing an annular space between the two tanks. This annular space is filled with liquid moderator which functions as a reflector to reflect neutrons back into the central reactor tank to increase the reproduction ratio. Means are provided for circulating and cooling the moderator material in both tanks and additional means are provided for controlling separately the volume of moderator in each tank, which latter means may be operated automatically by a neutron density monitoring device. The patent also shows an arrangement for controlling the chain reaction by injecting and varying an amount of poisoning material in the moderator used in the reflector portion of the reactor.

Vaccum assisted closure: an alternative strategy in the management of degloving injuries of the foot.

PubMed

Josty, I C; Ramaswamy, R; Laing, J H

2001-06-01

A case of a degloving injury to the foot is presented in a patient who also sustained severe contralateral lower-limb trauma. We report a technique for salvaging the foot by replacing the degloved skin as a full-thickness graft and securing it using the vacuum-assisted closure (VAC) device. A good outcome was achieved and technical tips are provided to facilitate reproduction of the procedure. Copyright 2001 The British Association of Plastic Surgeons.

The Use of the 'Preclosure' Technique for Antegrade Aspiration Thrombectomy with Large Catheters in Acute Limb Ischemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Funke, C., E-mail: claas_funke@hotmail.com; Pfiffner, R.; Husmann, M.

2013-04-15

This study was designed to assess retrospectively short- and mid-term outcomes of the use of a suture-mediated closure device to close the antegrade access in patients undergoing percutaneous aspiration thrombectomy with large catheters for acute leg ischemia. Between November 2005 and February 2010, a suture-mediated active closure system (ProGlide{sup Registered-Sign} 6F, Abbott) was placed before arterial sheath (mean 9 F, range 6-12 F) introduction in 101 patients (74 men, 73 %, mean age 70.1 {+-} 12.6 years standard deviation). Data regarding mortality, complications, and factors contributing to vascular complications at the access site was collected for 6 month after themore » intervention to detect device-related problems. As a coincidence, 77 patients had follow-up visits for a duplex ultrasound. There were a total of 19 vascular complications (19 %) at the puncture site, all of which were of hemorrhagic nature and none of which consisted of vessel occlusion. Two major outcome complications (2 %) occurred. A retroperitoneal hematoma and a serious inguinal bleeding required additive treatment and did not result in permanent sequelae. Nine cases involved death of which eight were not attributable to the closure and one remained unclear. Successful closure was achieved in 95 patients (94 %); additional manual compression was sufficient in the majority of the remaining patients. Numerous factors contributing to vascular complications were encountered. With acceptable short- and mid-term outcomes, the 'preclose' technique can be a reliable option for the closure of a large antegrade femoral access even for patients at a high risk of vascular complications, such as those undergoing aspiration thrombectomy.« less

Direct Percutaneous Left Ventricular Access and Port Closure

PubMed Central

Barbash, Israel M.; Saikus, Christina E.; Faranesh, Anthony Z.; Ratnayaka, Kanishka; Kocaturk, Ozgur; Chen, Marcus Y.; Bell, Jamie A.; Virmani, Renu; Schenke, William H.; Hansen, Michael S.; Slack, Michael C.; Lederman, Robert J.

2012-01-01

Objectives This study sought to evaluate feasibility of nonsurgical transthoracic catheter-based left ventricular (LV) access and closure. Background Implanting large devices, such as mitral or aortic valve prostheses, into the heart requires surgical exposure and repair. Reliable percutaneous direct transthoracic LV access and closure would allow new nonsurgical therapeutic procedures. Methods Percutaneous direct LV access was performed in 19 swine using real-time magnetic resonance imaging (MRI) and an “active” MRI needle antenna to deliver an 18-F introducer sheath. The LV access ports were closed percutaneously using a commercial ventricular septal defect occluder and an “active” MRI delivery cable for enhanced visibility. We used “permissive pericardial tamponade” (temporary fluid instillation to separate the 2 pericardial layers) to avoid pericardial entrapment by the epicardial disk. Techniques were developed in 8 animals, and 11 more were followed up to 3 months by MRI and histopathology. Results Imaging guidance allowed 18-F sheath access and closure with appropriate positioning of the occluder inside the transmyocardial tunnel. Of the survival cohort, immediate hemostasis was achieved in 8 of 11 patients. Failure modes included pericardial entrapment by the epicardial occluder disk (n = 2) and a true-apex entry site that prevented hemostatic apposition of the endocardial disk (n = 1). Reactive pericardial effusion (192 ± 118 ml) accumulated 5 ± 1 days after the procedure, requiring 1-time drainage. At 3 months, LV function was preserved, and the device was endothelialized. Conclusions Direct percutaneous LV access and closure is feasible using real-time MRI. A commercial occluder achieved hemostasis without evident deleterious effects on the LV. Having established the concept, further clinical development of this approach appears realistic. PMID:22192372

[Percutaneous closure of the patent ductus arteriosus in children with the Amplatzer Duct Occluder II].

PubMed

Parra-Bravo, José Rafael; Osuna-Izaguirre, Manuel Alfredo; Beirana-Palencia, Luisa; Gálvez-Cancino, Franco; Martínez-Monterrosas, Christian; Lazo-Cárdenas, César; Reyes-Vargas, César

2014-01-01

In the last decades, several devices have been used for the percutaneous closure of patent ductus arteriosus, with its own limitations and risks. The Amplatzer Duct Occluder II has been designed to overcome those limitations and reduce risks. We described our initial series of patients who underwent percutaneous closure of patent ductus arteriosus with the Amplatzer Duct Occluder II, emphasis on the technical aspects of the procedure. We reviewed the clinical records of 9 patients with patent ductus arteriosus who underwent percutaneous closure with the Amplatzer Duct Occluder II. Median age was 24 months (range 8-51 months) and the median weight was 10.7kg (range 6-16.3kg). The minimal ductus arteriosus diameter was 2.7mm (1-5mm). Implantation was successful in all cases. The devices most commonly used (33.3%) were the dimensions 4-4mm (3 patients), in 2 patients were used 3-4mm and in the rest of the patients were employed occluder other sizes. Four cases showed slight residual flow immediately after implantation. Total closure was achieved in 24h in 8 of 9 patients (89%). There was no embolization of the occluder or deaths during the procedure and we only observed one minor complication. The Amplatzer Duct Occluder II in this series was effective in 89% of the patients at 24hs after the procedure and 100% follow-up. The implantation was safe and no major complications were observed. The occlusion rate is comparable to those reported for the Amplatzer Duct Occluder I. Copyright © 2013 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

Trial occlusion to assess the risk of persistent pulmonary arterial hypertension after closure of a large patent ductus arteriosus in adolescents and adults with elevated pulmonary artery pressure.

PubMed

Zhang, Duan-Zhen; Zhu, Xian-Yang; Lv, Bei; Cui, Chun-Sheng; Han, Xiu-Min; Sheng, Xiao-Tang; Wang, Qi-Guang; Zhang, Po

2014-08-01

No method is available to predict whether patients with patent ductus arteriosus (PDA) and severe pulmonary arterial hypertension (PAH) will show persistent postprocedural PAH (PP-PAH) after PDA closure. This study evaluated the usefulness of trial occlusion for predicting PP-PAH after transcatheter PDA closure in patients with severe PAH. Trial occlusion was performed in 137 patients (age ≥12 years) with PDA and severe PAH. All patients undergoing trial occlusion had a mean pulmonary artery pressure ≥45 mm Hg, pulmonary:systemic flow (Qp/Qs) ratio >1.5, and pulmonary:systemic resistance (Rp/Rs) ratio <0.7. A total of 135 patients (98%) showing stable hemodynamics during occlusion trial underwent successful device closure. Linear correlation analysis revealed weak or moderate relationships between the baseline and post-trial pulmonary artery pressures and pulmonary:systemic pressure (Pp/Ps) ratios. Patients were followed up for 1 to 10 years (median: 5 years). PP-PAH (systolic pulmonary artery pressure >50 mm Hg by Doppler echocardiography) was detected in 17 patients (13%), who displayed no significant differences in sex and age compared with patients without PP-PAH. According to discriminant analysis, the strongest discriminators between patients with and without PP-PAH were the baseline left ventricular end-diastolic volume and the baseline and post-trial systolic Pp/Ps ratios. In particular, a post-trial systolic Pp/Ps ratio >0.5 correctly classified 100% of the PP-PAH and non-PAH patients. Trial occlusion is a feasible method to predict PP-PAH in patients with PDA and severe PAH. A post-trial systolic Pp/Ps ratio >0.5 indicates a high risk of PP-PAH occurrence after device closure. © 2014 American Heart Association, Inc.

Efficacy of stapler versus hand-sewn closure after distal pancreatectomy (DISPACT): a randomised, controlled multicentre trial.

PubMed

Diener, Markus K; Seiler, Christoph M; Rossion, Inga; Kleeff, Jörg; Glanemann, Matthias; Butturini, Giovanni; Tomazic, Ales; Bruns, Christiane J; Busch, Olivier R C; Farkas, Stefan; Belyaev, Orlin; Neoptolemos, John P; Halloran, Christopher; Keck, Tobias; Niedergethmann, Marco; Gellert, Klaus; Witzigmann, Helmut; Kollmar, Otto; Langer, Peter; Steger, Ulrich; Neudecker, Jens; Berrevoet, Frederik; Ganzera, Silke; Heiss, Markus M; Luntz, Steffen P; Bruckner, Thomas; Kieser, Meinhard; Büchler, Markus W

2011-04-30

The ideal closure technique of the pancreas after distal pancreatectomy is unknown. We postulated that standardised closure with a stapler device would prevent pancreatic fistula more effectively than would a hand-sewn closure of the remnant. This multicentre, randomised, controlled, parallel group-sequential superiority trial was done in 21 European hospitals. Patients with diseases of the pancreatic body and tail undergoing distal pancreatectomy were eligible and were randomly assigned by central randomisation before operation to either stapler or hand-sewn closure of the pancreatic remnant. Surgical performance was assessed with intraoperative photo documentation. The primary endpoint was the combination of pancreatic fistula and death until postoperative day 7. Patients and outcome assessors were masked to group assignment. Interim and final analysis were by intention to treat in all patients in whom a left resection was done. This trial is registered, ISRCTN18452029. Between Nov 16, 2006, and July 3, 2009, 450 patients were randomly assigned to treatment groups (221 stapler; 229 hand-sewn closure), of whom 352 patients (177 stapler, 175 hand-sewn closure) were analysed. Pancreatic fistula rate or mortality did not differ between stapler (56 [32%] of 177) and hand-sewn closure (49 [28%] of 175; OR 0·84, 95% CI 0·53–1·33; p=0·56). One patient died within the fi rst 7 days after surgery in the hand-sewn group; no deaths occurred in the stapler group. Serious adverse events did not differ between groups. Stapler closure did not reduce the rate of pancreatic fistula compared with hand-sewn closure for distal pancreatectomy. New strategies, including innovative surgical techniques, need to be identified to reduce this adverse outcome. German Federal Ministry of Education and Research.

Comparing Gonioscopy With Visante and Cirrus Optical Coherence Tomography for Anterior Chamber Angle Assessment in Glaucoma Patients.

PubMed

Hu, Cindy X; Mantravadi, Anand; Zangalli, Camila; Ali, Mohsin; Faria, Bruno M; Richman, Jesse; Wizov, Sheryl S; Razeghinejad, M Reza; Moster, Marlene R; Katz, L Jay

2016-02-01

The aim of this study was to compare gonioscopy with Visante and Cirrus optical coherence tomography (OCT) for identifying angle structures and the presence of angle closure in patients with glaucoma. A secondary objective was to assess interrater agreement for gonioscopy grading among 3 independent examiners. Gonioscopy grading using Spaeth Classification and determination of angle-closure risk was performed on 1 randomly selected eye for 50 phakic patients. Images of the same eye using both Visante and Cirrus OCT were obtained in both light and dark conditions. Agreement of angle closure among 3 devices and interrater agreement for gonioscopy were determined using Cohen's κ (K) or Kendall's coefficient of concordance (W). Of the 50 patients, 60% were female, 64% were white, and the mean age was 62 years. Angle closure was detected in 18%, 16%, and 48% of quadrants with Visante, Cirrus, and gonioscopy, respectively. The scleral spur was identified in 56% and 50% of quadrants with Visante and Cirrus OCT, respectively. Visante and Cirrus OCT showed moderate agreement in detecting angle closure (K=0.42 light, K=0.53 dark) but slight-to-fair agreement with gonioscopy (Visante K=0.25, Cirrus K=0.15). Gonioscopy demonstrated substantial agreement in angle closure (K=0.65 to 0.68) and angle-closure risk assessment (W=0.83) among 3 examiners. Visante and Cirrus OCT imaging may have limited ability to identify angle closure because of difficulty identifying angle structures. Gonioscopy by well-trained clinicians had remarkably consistent agreement for identifying angle-closure risk.

Intracardiac echocardiography to guide closure of atrial septal defects in children less than 15 kilograms.

PubMed

Patel, Angira; Cao, Qi-Ling; Koenig, Peter R; Hijazi, Ziyad M

2006-08-01

Intracardiac echocardiography (ICE) is increasingly replacing transesophageal echocardiography (TEE) as the primary imaging technique to guide device closure of atrial septal defects (ASD). Owing to the length of the procedure, the use of TEE requires general anesthesia. Investigators have reported the usefulness of ICE in adults and children. However, little is known about the use of ICE in children whose weight is <15 kg. Therefore, this study examines the use of ICE guided secundum ASD closure in children <15 kg. Nineteen patients with a median age of 3.1 years (range 1.8-4.8), and median weight of 13.2 kg (range 8.0-14.4) underwent transcatheter occlusion (Amplatzer occluder) of a secundum ASD using ICE guidance. ICE was performed using an Acunav catheter. The ICE catheter (10 F shaft) was introduced into an 11 F sheath in a contralateral femoral vein. Diagnostic as well as periprocedure imaging was obtained. Sixteen patients had single, and three had multiple defects. Median defect size as measured by ICE was 16 mm (range 2.5-25). The median balloon stretched diameter (obtained in eight patients) was 18 mm (range 10-21); the median size of the defect for these eight patients was 15 mm (range of 8-20). Both techniques for measuring the defect correlated well with r = 0.94. The ASD occluder size ranged from 7 to 26 mm with a median of 18 mm. The procedure was successful in 16 patients who had a device implanted and no residual shunt. ASD occlusion was not attempted in two patients due to deficient rims and in one patient, the attempt failed due to left atrial disk prolapse through the ASD. Four patients experienced transient complications during the catheter procedure, including supra ventricular tachycardia, sinus bradycardia, and two with complete heart block (resolving with device removal); all had subsequent successful device placement. No complications were attributed to the use of ICE and specifically, no vascular injury was noted. Comparable to results with larger patients, ICE provides adequate imaging (preprocedure diagnosis and periprocedure guidance) during device occlusion of secundum ASDs with no significant complications. Thus, ICE can successfully be used in the closure of ASD in smaller patients (<15 kg) and eliminate the need for endotracheal intubation.

Closure Report for Corrective Action Unit 426: Cactus Spring Waste Trenches, Tonopah Test Range, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dave Madsen

This Closure Report provides the documentation for closure of the Cactus Spring Waste Trenches Corrective Action Unit (CAU) 426. The site is located on the Tonopah Test Range, approximately 225 kilometers northwest of Las Vegas, NV. CAU 426 consists of one corrective action site (CAS) which is comprised of four waste trenches. The trenches were excavated to receive solid waste generated in support of Operation Roller Coaster, primary the Double Tracks Test in 1963, and were subsequently backfilled. The Double Tracks Test involved use of live animals to assess the biological hazards associated with the nonnuclear detonation of plutonium-bearing devices.more » The Nevada Division of Environmental Protection approved Corrective Action Plan (CAP)which proposed ''capping'' methodology. The closure activities were completed in accordance with the approved CAP and consisted of constructing an engineered cover in the area of the trenches, constructing/planting a vegetative cover, installing a perimeter fence and signs, implementing restrictions on future use, and preparing a Post-Closure Monitoring Plan.« less

[New technology for prevention of embolic events in atrial fibrillation: a systematic review on percutaneous endovascular left atrial appendage closure].

PubMed

Danna, Paolo; Sagone, Antonio; Proietti, Riccardo; Arensi, Andrea; Viecca, Maurizio; Santangeli, Pasquale; Di Biase, Luigi; Natale, Andrea

2012-09-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia. The mortality rate of patients with AF is doubled as compared to non-fibrillating controls. The most relevant complication of AF is a major increase in the risk of stroke. The gold standard in reducing cerebrovascular events in AF is warfarin therapy, which is not free from contraindications and limitations. The left atrial appendage (LAA) is the main source of emboli causing stroke in AF. LAA closure is a seducing approach to stroke risk reduction in AF without anticoagulation. Since 1949, heart surgeons have performed LAA closure or amputation in patients with AF. Percutaneous endovascular LAA closure is a new, less invasive, technique to reach the goal. Several devices have been used to perform this intervention, and the results of published trials are encouraging in terms of effectiveness and relative safety of this attractive technique. In this review we examine the published trials and data on percutaneous LAA closure, with particular attention to the risks and benefits of this procedure.

Multiple plate hydrostatic viscous damper

NASA Technical Reports Server (NTRS)

Ludwig, L. P. (Inventor)

1981-01-01

A device for damping radial motion of a rotating shaft is described. The damper comprises a series of spaced plates extending in a radial direction. A hydraulic piston is utilized to place a load in these plates. Each annular plate is provided with a suitable hydrostatic bearing geometry on at least one of its faces. This structure provides a high degree of dampening in a rotor case system of turbomachinery in general. The damper is particularly useful in gas turbine engines.

Ion-sculpting of nanopores in amorphous metals, semiconductors, and insulators

DOE Office of Scientific and Technical Information (OSTI.GOV)

George, H. Bola; Madi, Charbel S.; Aziz, Michael J.

2010-06-28

We report the closure of nanopores to single-digit nanometer dimensions by ion sculpting in a range of amorphous materials including insulators (SiO{sub 2} and SiN), semiconductors (a-Si), and metallic glasses (Pd{sub 80}Si{sub 20})--the building blocks of a single-digit nanometer electronic device. Ion irradiation of nanopores in crystalline materials (Pt and Ag) does not cause nanopore closure. Ion irradiation of c-Si pores below 100 deg. C and above 600 deg. C, straddling the amorphous-crystalline dynamic transition temperature, yields closure at the lower temperature but no mass transport at the higher temperature. Ion beam nanosculpting appears to be restricted to materials thatmore » either are or become amorphous during ion irradiation.« less

[Stapler and manual bronchial anastomosis--results of a consecutive trial series].

PubMed

Junginger, T; Walgenbach, S; Pichlmaier, H

1989-01-01

After lobectomy and pneumonectomy in experimental evaluations stapled bronchial closures showed the lowest incidence of inflammatory reaction and the highest strength determined by leakage pressure compared with other suture material. A total of 233 lung resections-performed at Surgical University Clinic Köln-Lindenthal and the Clinic for General and Abdominal Surgery of the Johannes-Gutenberg-Universität Mainz--were reviewed. Mechanical stapling reduced the rate of bronchopleural fistulas to 2.0% compared with 7.1% after manual suturing. In parallel, mortality related to bronchial stump leakage decreased to 0.7%. Main advantages of bronchial closure with staplers are the simplicity of their use, the speed and the uniformity of the closure. Thereby stapling devices are valuable completions in pulmonary surgery.

Intraoperative three-dimensional transesophageal echocardiography for assessing the defect geometries of mitral prosthetic paravalvular leak during transcatheter closure.

PubMed

Wei, Jeng; Yin, Wei-Hsian; Lee, Yung-Tsai; Hsiung, Ming C; Tsai, Shen-Kou; Chuang, Yi Cheng; Ou, Ching-Huei; Chou, Yi-Pen

2015-03-01

Paravalvular leaks (PVLs) are a common complication of prosthetic valve replacement. Use of the transcatheter intervention technique is a suitable alternative in high-risk patients who may not tolerate repeat surgery. Common reasons for failure of this demanding intervention include poor imaging quality and unsuitable anatomy. The purpose of this study was to assess the usefulness and the incremental value of real-time three-dimensional (RT 3D) transesophageal echocardiography (TEE) over two-dimensional (2D) TEE findings in the evaluation of the geometry and track of mitral PVLs during transcatheter closure. Five patients with six mitral PVLs at high risk for repeat surgery underwent transcatheter leak closure. Intraoperative RT 3DTEE was used to assess the location, shape, number, and size of the defects. Transapical approaches were used in all cases with fluoroscopic and RT 3D TEE guidance of the wire and catheter, device positioning, and assessment of residual leak after the procedure. In all of the cases, defects with irregular crescent shapes and distorted tracks were clearly delineated by RT 3D TEE. This was compared to those results obtained through 2D TEE, which was unable to characterize the defects. Three cases showed small leaks, which were completely occluded with a patent ductus arteriosus (PDA) device in two cases, and a muscular ventricular septal defect (mVSD) occluder combined with coil devices in one case. One case involved a large leak and early device embolization of the muscular VSD occluder, which was removed surgically, and demonstrated a crescent-shaped defect. One patient had two releaks 2 months subsequent to the procedure due to two new extended leaks at the tails of the crescent-shaped defect. RT 3D TEE can clearly delineate the geometries of defects in their entirety, including shape, size, and location of the defect and track canal. It would also appear that RT 3D TEE is superior to 2D TEE in the process of guiding the wire through the difficult canal anatomy, facilitating the overall procedure. The small mitral PVLs can be completely occluded, but subsequent complications occurred with large defect closures because of embolization or releak. Therefore, transcatheter closure of PVLs seems to be an attractive alternative for these patients, but newer occluder designs that better conform to leak geometry will be required to improve outcomes. Copyright © 2014. Published by Elsevier Taiwan.

Long-term outcome after percutaneous closure of persistent left superior caval vein draining into the left atrium: a contrast-enhanced CT study.

PubMed

Marini, Davide; Castagno, Matteo; Millesimo, Michele; Ferroni, Francesca; Ferraro, Gaetana; Pace Napoleone, Carlo; Agnoletti, Gabriella

2017-10-01

Data regarding long-term outcome after percutaneous closure of left superior caval vein draining into the left atrium are lacking. The aim of the present study was to report the long-term follow-up by using contrast-enhanced CT. In all, three patients underwent percutaneous closure of left superior caval vein draining into the left atrium between 2005 and 2015. All of them were evaluated clinically and underwent contrast-enhanced CT. In one patient, the Amplatzer® Septal Occluder was used. In two patients, the Amplatzer® Vascular Plug type-1 was preferred: the device size/LSVC diameter ratio was 1.7 in the child and 1.2 in the adult. There were no early-onset or long-term onset complications. CT was performed 1, 2, and 10 years after the procedure, respectively. Complete occlusion of the vessel was documented in all. After 10 years since the procedure, CT revealed a persistent trivial residual shunt through the accessory hemiazygos vein in one patient, in whom the device was implanted above its drainage into the left superior caval vein. When an Amplatzer® Vascular Plug type-1 is oversized compared with the venous vessel diameter, it immediately assumes a dog-bone shape that disappears early to regain its shape memory and nominal size. Percutaneous occlusion of left superior caval vein draining into the left atrium has excellent early and long-term outcomes. The optimal implantation of the device is below the drainage of the accessory hemiazygos vein, when present. The device might be oversized compared with the left superior caval vein diameter according to the age of the patient.

Percutaneous Steerable Robotic Tool Delivery Platform and Metal MEMS Device for Tissue Manipulation and Approximation: Closure of Patent Foramen Ovale in an Animal Model

PubMed Central

Vasilyev, Nikolay V.; Gosline, Andrew H.; Butler, Evan; Lang, Nora; Codd, Patrick J.; Yamauchi, Haruo; Feins, Eric N.; Folk, Chris R.; Cohen, Adam L.; Chen, Richard; Zurakowski, David; del Nido, Pedro J.; Dupont, Pierre E

2013-01-01

Background Beating-heart image-guided intracardiac interventions have been evolving rapidly. To extend the domain of catheter-based and transcardiac interventions into reconstructive surgery, a new robotic tool delivery platform (TDP) and tissue approximation device have been developed. Initial results employing these tools to perform patent foramen ovale (PFO) closure are described. Methods and Results A robotic TDP comprised of superelastic metal tubes provides the capability of delivering and manipulating tools and devices inside the beating heart. A new device technology is also presented that utilizes a metal-based MicroElectroMechanical Systems (MEMS) manufacturing process to produce fully-assembled and fully-functional millimeter-scale tools. As a demonstration of both technologies, a PFO creation and closure was performed in a swine model. In the first group of animals (N=10), a preliminary study was performed. The procedural technique was validated with a transcardiac handheld delivery platform and epicardial echocardiography, video-assisted cardioscopy and fluoroscopy. In the second group (N=9), the procedure was performed percutaneously using the robotic TDP under epicardial echocardiography and fluoroscopy imaging. All PFO’s were completely closed in the first group. In the second group, the PFO was not successfully created in 1 animal, and the defects were completely closed in 6 of the 8 remaining animals. Conclusions In contrast to existing robotic catheter technologies, the robotic TDP utilizes a combination of stiffness and active steerability along its length to provide the positioning accuracy and force application capability necessary for tissue manipulation. In combination with a MEMS tool technology, it can enable reconstructive procedures inside the beating heart. PMID:23899870

Percutaneous closure of hypertensive ductus arteriosus.

PubMed

Zabal, Carlos; García-Montes, José Antonio; Buendía-Hernández, Alfonso; Calderón-Colmenero, Juan; Patiño-Bahena, Emilia; Juanico-Enriquez, Antonio; Attie, Fause

2010-04-01

The Amplatzer duct occluder (ADO) has been used with success to close large patent ductus arteriosus (PDA), but some problems exist especially with hypertensive PDAs, such as incomplete closure, haemolysis, left pulmonary artery stenosis, obstruction of the descending aorta and progressive pulmonary vascular disease. We analysed a group of 168 patients with isolated PDA and pulmonary artery systolic pressure (PSAP) > or =50 mm Hg. Mean age was 10.3 +/- 14.3 years (median 3.9), PDA diameter was 6.4 +/- 2.9 mm (median 5.9), PASP was 63.5 +/- 16.2 mm Hg (median 60), Qp/Qs was 2.7 +/- 1.2 (median 2.5), total pulmonary resistance index (PRI) was 3.69 +/- 2.15 (median 3.35) and vascular PRI was 2.73 +/- 1.72 (median 2.37). We used ADOs in 145 (86.3%) cases, Amplatzer muscular ventricular septal defect occluders (AMVSDO) in 18 (10.7%), Amplatzer septal occluders (ASO) in three (1.8%) and the Gianturco-Grifka device in two (1.2%) cases. Device diameter was 106.3% +/- 51% higher than PDA diameter. PASP decreased after occlusion to 42.5 +/- 13.3 mm Hg (p<0.00001). Immediately after closure, no or trivial shunt was present in 123 (74.5%) cases. Immediate complications were device embolisation in five (3%) cases and descending aortic obstruction in one case. The overall success rate was 98.2%. Follow-up in 145 (86.3%) cases for 37.1 +/- 24 months (median 34.1) showed further decrease of the PASP to 30.1 +/- 7.7 mm Hg (p<0.0001). Percutaneous treatment of hypertensive PDA is safe and effective. ADO works well for most cases, but sometimes other devices (MVSDO or ASO) have to be used. When cases are selected adequately, pulmonary pressures decrease immediately and continue to fall with time.

Air riding seal with purge cavity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sexton, Thomas D; Mills, Jacob A

An air riding seal for a turbine in a gas turbine engine, where an annular piston is axial moveable within an annular piston chamber formed in a stator of the turbine and forms a seal with a surface on the rotor using pressurized air that forms a cushion in a pocket of the annular piston. A purge cavity is formed on the annular piston and is connected to a purge hole that extends through the annular piston to a lower pressure region around the annular piston or through the rotor to an opposite side. The annular piston is sealed alsomore » with inner and outer seals that can be a labyrinth seal to form an additional seal than the cushion of air in the pocket to prevent the face of the air riding seal from overheating.« less

Spontaneous vortex nanodomain arrays at ferroelectric heterointerfaces.

PubMed

Nelson, Christopher T; Winchester, Benjamin; Zhang, Yi; Kim, Sung-Joo; Melville, Alexander; Adamo, Carolina; Folkman, Chad M; Baek, Seung-Hyub; Eom, Chang-Beom; Schlom, Darrell G; Chen, Long-Qing; Pan, Xiaoqing

2011-02-09

The polarization of the ferroelectric BiFeO(3) sub-jected to different electrical boundary conditions by heterointerfaces is imaged with atomic resolution using a spherical aberration-corrected transmission electron microscope. Unusual triangular-shaped nanodomains are seen, and their role in providing polarization closure is understood through phase-field simulations. Heterointerfaces are key to the performance of ferroelectric devices, and this first observation of spontaneous vortex nanodomain arrays at ferroelectric heterointerfaces reveals properties unlike the surrounding film including mixed Ising-Néel domain walls, which will affect switching behavior, and a drastic increase of in-plane polarization. The importance of magnetization closure has long been appreciated in multidomain ferromagnetic systems; imaging this analogous effect with atomic resolution at ferroelectric heterointerfaces provides the ability to see device-relevant interface issues. Extension of this technique to visualize domain dynamics is envisioned.

CLOSURE DEVICE

DOEpatents

Linzell, S.M.; Dorcy, D.J.

1958-08-26

A quick opening type of stuffing box employing two banks of rotatable shoes, each of which has a caraming action that forces a neoprene sealing surface against a pipe or rod where it passes through a wall is presented. A ring having a handle or wrench attached is placed eccentric to and between the two banks of shoes. Head bolts from the shoes fit into slots in this ring, which are so arranged that when the ring is rotated a quarter turn in one direction the shoes are thrust inwardly to cramp the neopnrene about the pipe, malting a tight seal. Moving the ring in the reverse direction moves the shoes outwardly and frees the pipe which then may be readily removed from the stuffing box. This device has particular application as a closure for the end of a coolant tube of a neutronic reactor.

Simultaneous maxillary distraction osteogenesis using a twin-track distraction device combined with alveolar bone grafting in cleft patients: preliminary report of a technique.

PubMed

Suzuki, Eduardo Yugo; Watanabe, Masayo; Buranastidporn, Boonsiva; Baba, Yoshiyuki; Ohyama, Kimie; Ishii, Masatoshi

2006-01-01

The simultaneous use of cleft reduction and maxillary advancement by distraction osteogenesis has not been applied routinely because of the difficulty in three-dimensional control and stabilization of the transported segments. This report describes a new approach of simultaneous bilateral alveolar cleft reduction and maxillary advancement by distraction osteogenesis combined with autogenous bone grafting. A custom-made Twin-Track device was used to allow bilateral alveolar cleft closure combined with simultaneous maxillary advancement, using distraction osteogenesis and a rigid external distraction system in a bilateral cleft lip and palate patient. After a maxillary Le Fort I osteotomy, autogenous iliac bone graft was placed in the cleft spaces before suturing. A latency period of six days was observed before activation. The rate of activation was one mm/d for the maxillary advancement and 0.5 mm/d for the segmental transport. Accordingly, the concave facial appearance was improved with acceptable occlusion, and complete bilateral cleft closure was attained. No adjustments were necessary to the vector of the transported segments during the activation and no complications were observed. The proposed Twin-Track device, based on the concept of track-guided bone transport, permitted three-dimensional control over the distraction processes allowing simultaneous cleft closure, maxillary distraction, and autogenous bone grafting. The combined simultaneous approach is extremely advantageous in correcting severe deformities, reducing the number of surgical interventions and, consequently, the total treatment time.

Safety and efficacy of Cardi-O-fix occluder for percutaneous closure of a patent foramen ovale

PubMed Central

Zhao, Enfa; Liu, Wenjuan; Zhang, Yushun; Cheng, Gesheng; Du, Yajuan; He, Lu; Wang, Xingye; He, Xumei

2017-01-01

Abstract Background: Amplatzer occluder and Cardio-O-fix occluder are currently used in percutaneous closure of patent foramen ovale. However, there is still a lack of relevant reports comparison the differences between them. The aim of this study was to evaluate the short-term and mid-term safety and efficacy of the Cardi-O-fix occluder in preventing recurrent cerebrovascular events in patients with a patent foramen ovale (PFO). Methods: We enrolled 246 patients (105 men) with a PFO from May 30, 2013 to March 30, 2015 in this single-center prospective study. All patients were treated by PFO interventional closure, with the Cardi-O-fix PFO occluder being used in 180 patients and the Amplatzer PFO occluder being utilized in the remaining 66 patients. After the procedure, we verified the safety and efficacy of different devices using contrast transthoracic echocardiography. Results: Neither recurrent stroke nor death was encountered during the follow-up of 12 months. Transient ischemic attack (TIA) was noted in 2 patients (1.1%) in the Cardi-O-fix PFO occluder group, and 1 patient suffered from TIA (1.5%) in the Amplatzer PFO occluder group. Among them, only 1 patient exhibited a small right to left shunt (RLS). There was no statistical difference in recurrent cerebral ischemic events. Three cases of paroxysmal atrial fibrillation were observed in the Cardi-O-fix PFO occluder group. One reverted spontaneously to sinus rhythm and the other 2 cases had pharmacologic conversion to sinus rhythm. One case of paroxysmal atrial fibrillation occurred in the Amplatzer group, which underwent pharmacologic conversion to sinus rhythm. There was no significant difference between the 2 groups regarding incidence of arrhythmia. No occluder translocation, erosion, pericardial effusion, and puncture site bleeding were observed in the 2 groups within 12 months of follow-up. The complete closure rates of the Cardi-O-fix and Amplatzer PFO occluder devices at the 12 months after the procedure were 73.9% and 63.6%, respectively, and the effective closure rates were 90.6% and 86.4%, respectively. There was no statistically significant difference in the complete closure rate and effective occlusion rate (P > 0.05) between the devices. Conclusions: There was no significant difference in the short- and mid-term efficacy and safety between the Cardi-O-fix PFO occluder and Amplatzer PFO occluder. The efficacy and safety of the Cardi-O-fix occluder were comparable to those of the Amplatzer PFO occluder. PMID:28383438

Perceptions of transcatheter device closure of patent ductus arteriosus in veterinary cardiology and evaluation of a canine model to simulate device placement: a preliminary study.

PubMed

Saunders, A B; Keefe, L; Birch, S A; Wierzbicki, M A; Maitland, D J

2017-06-01

The purpose of this study was to evaluate a canine patent ductus arteriosus (PDA) model developed for practicing device placement and to determine practices and perceptions regarding transcatheter closure of PDA from the veterinary cardiology community. A silicone model was developed from images obtained from a dog with a PDA and device placement was performed with catheter equipment and a document camera to simulate fluoroscopy. A total of 36 individuals including 24 diplomates and 12 residents participated, and the feedback was obtained. The study included an initial questionnaire, practice with the model, observation of device placement using the model, and a follow-up questionnaire. A total of 92% of participants including 100% of residents indicated they did not have the opportunity to practice device placement before performing the procedure and obtained knowledge of the procedure from reading journal articles or observation. Participants indicated selecting the appropriate device size (30/36, 83%) and ensuring the device is appropriately positioned before release (18/36, 50%) as the most common areas of difficulty with device placement. Confidence level was higher after practicing with the model for residents when compared with diplomates and for participants that had performed 1-15 procedures when compared with those that had performed >15 procedures. These findings suggest those that have performed fewer procedures may benefit the most from practicing with a model. This preliminary study demonstrates the feasibility of a PDA model for practicing device placement and suggests that there is a potential benefit from providing additional training resources. Copyright © 2017 Elsevier B.V. All rights reserved.

Multi-functional annular fairing for coupling launch abort motor to space vehicle

NASA Technical Reports Server (NTRS)

Camarda, Charles J. (Inventor); Scotti, Stephen J. (Inventor); Buning, Pieter G. (Inventor); Bauer, Steven X. S. (Inventor); Engelund, Walter C. (Inventor); Schuster, David M. (Inventor)

2011-01-01

An annular fairing having aerodynamic, thermal, structural and acoustic attributes couples a launch abort motor to a space vehicle having a payload of concern mounted on top of a rocket propulsion system. A first end of the annular fairing is fixedly attached to the launch abort motor while a second end of the annular fairing is attached in a releasable fashion to an aft region of the payload. The annular fairing increases in diameter between its first and second ends.

A microprocessor-based table lookup approach for magnetic bearing linearization

NASA Technical Reports Server (NTRS)

Groom, N. J.; Miller, J. B.

1981-01-01

An approach for producing a linear transfer characteristic between force command and force output of a magnetic bearing actuator without flux biasing is presented. The approach is microprocessor based and uses a table lookup to generate drive signals for the magnetic bearing power driver. An experimental test setup used to demonstrate the feasibility of the approach is described, and test results are presented. The test setup contains bearing elements similar to those used in a laboratory model annular momentum control device.

Signal and power roll ring testing update

NASA Technical Reports Server (NTRS)

Smith, Dennis W.

1989-01-01

The development of the roll ring as a long-life, low-torque alternative to the slip ring is discussed. A roll ring consists of one or more circular flexures captured by their own spring force in the annular space between two concentric conductors or contact rings. The advantages of roll rings over other types of electrical transfer devices are: extremely low drag torque, high transfer efficiencies in high-power configurations, extremely low wear debris generation, long life, and low weight for high-power applications.

No evidence that manual closure of the bronchial stump has a lower failure rate than mechanical stapler closure following anatomical lung resection

PubMed Central

Zakkar, Mustafa; Kanagasabay, Robin; Hunt, Ian

2014-01-01

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether manual closure of the bronchial stump is safer with lower failure rates than mechanical closure using a stapling device following anatomical lung resection. One hundred and twenty-nine papers were identified using the search below. Eight papers presented the best evidence to answer the clinical question as they included sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates and operation time were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. When looking at manual vs mechanical staples, it was noted that stapler failure can occur in around 4% of cases. The rate of bronchopleural fistula (BPF) development varied more in patients who underwent manual closure (1.5–12.5%) than in patients who underwent mechanical closure (1–5.7%). Although most of the studies reviewed showed no statistical differences between manual and mechanical closure in terms of BPF development, one study, however, showed that manual closure was significantly associated with lower numbers of postoperative BPF, while another study showed that mechanical closure is significantly associated with lower incidence of BPF. When looking at the role of the learning curve and training opportunities, it seems that the surgeon's inexperience when using mechanical staples can contribute to BPF development. A surgeon's experience can play a major role in the prevention of BPF development in patients having manual closure. Manual closure can provide a cheap and reliable technique when compared with costs incurred from using staplers, it is applicable in all situations and can be taught to surgeons in training with an acceptable risk. However, there is a lack of evidence to suggest that manual closure is better than mechanical stapler closure following anatomical lung resection. PMID:24351508

Demagnetization of Nd 2Fe 14B, Pr 2Fe 14B, and Sm 2Co 17 Permanent Magnets in Spallation Irradiation Fields

DOE PAGES

Simos, Nikolaos; Ozaki, S.; Mokhov, N.; ...

2018-02-27

Prompted by the need for radiation-resistant permanent magnets for insertion devices (IDs) of high-brilliance next-generation synchrotrons such as the National Synchrotron Light Source II, the demagnetization of Nd 2Fe 14B and Pr 2Fe 14B was studied after exposure to a mixed irradiating field. Degradation and damage of the permanent magnetic material by components of electromagnetic showers induced in magnets by intense high-energy electron beams will alter the magnetic field structure of the IDs. Plate-like Nd 2Fe 14B magnets were irradiated to 1.8 Grad dose and were evaluated against Pr 2Fe 14B magnets irradiated to a lower dose of 20 Mrad.more » In addition, annular Sm 2Co 17 and Nd 2Fe 14B magnets integrated within a ferrofluidic feedthrough (FFFT) rotary seal were also irradiated to dose levels of 2 Grad for Sm 2Co 17 and 20 Mrad for Nd 2Fe 14B. Post-irradiation measurements of the magnetic intensity revealed that severe demagnetization exceeding 85% occurs in Nd 2Fe 14B magnets after only 50 Mrad dose and over 87% for Pr 2Fe 14B after 10 Mrad dose. The annular-shaped Sm 2Co 17 magnets of the FFFTs were almost insensitive to irradiation up to a dose of 2 Grad. Annular-shaped Nd 2Fe 14B magnets also showed resistance to demagnetization, a direct consequence of the annular shape which is characterized by the removal of the stronger demagnetizing field present at the center of a disk-like magnet. As a result, the sensitivity of boron-based permanent magnets to neutron energy (thermal versus fast) was also assessed via specifically designed experiments and discussed.« less

Geometry optimization of linear and annular plasma synthetic jet actuators

NASA Astrophysics Data System (ADS)

Neretti, G.; Seri, P.; Taglioli, M.; Shaw, A.; Iza, F.; Borghi, C. A.

2017-01-01

The electrohydrodynamic (EHD) interaction induced in atmospheric air pressure by a surface dielectric barrier discharge (DBD) actuator has been experimentally investigated. Plasma synthetic jet actuators (PSJAs) are DBD actuators able to induce an air stream perpendicular to the actuator surface. These devices can be used in the field of aerodynamics to prevent or induce flow separation, modify the laminar to turbulent transition inside the boundary layer, and stabilize or mix air flows. They can also be used to enhance indirect plasma treatment effects, increasing the reactive species delivery rate onto surfaces and liquids. This can play a major role in plasma processing and chemical kinetics modelling, where often only diffusive mechanisms are considered. This paper reports on the importance that different electrode geometries can have on the performance of different PSJAs. A series of DBD aerodynamic actuators designed to produce perpendicular jets has been fabricated on two-layer printed circuit boards (PCBs). Both linear and annular geometries were considered, testing different upper electrode distances in the linear case and different diameters in the annular one. An AC voltage supplied at a peak of 11.5 kV and a frequency of 5 kHz was used. Lower electrodes were connected to the ground and buried in epoxy resin to avoid undesired plasma generation on the lower actuator surface. Voltage and current measurements were carried out to evaluate the active power delivered to the discharges. Schlieren imaging allowed the induced jets to be visualized and gave an estimate of their evolution and geometry. Pitot tube measurements were performed to obtain the velocity profiles of the PSJAs and to estimate the mechanical power delivered to the fluid. The optimal values of the inter-electrode distance and diameter were found in order to maximize jet velocity, mechanical power or efficiency. Annular geometries were found to achieve the best performance.

Demagnetization of Nd 2Fe 14B, Pr 2Fe 14B, and Sm 2Co 17 Permanent Magnets in Spallation Irradiation Fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simos, Nikolaos; Ozaki, S.; Mokhov, N.

Prompted by the need for radiation-resistant permanent magnets for insertion devices (IDs) of high-brilliance next-generation synchrotrons such as the National Synchrotron Light Source II, the demagnetization of Nd 2Fe 14B and Pr 2Fe 14B was studied after exposure to a mixed irradiating field. Degradation and damage of the permanent magnetic material by components of electromagnetic showers induced in magnets by intense high-energy electron beams will alter the magnetic field structure of the IDs. Plate-like Nd 2Fe 14B magnets were irradiated to 1.8 Grad dose and were evaluated against Pr 2Fe 14B magnets irradiated to a lower dose of 20 Mrad.more » In addition, annular Sm 2Co 17 and Nd 2Fe 14B magnets integrated within a ferrofluidic feedthrough (FFFT) rotary seal were also irradiated to dose levels of 2 Grad for Sm 2Co 17 and 20 Mrad for Nd 2Fe 14B. Post-irradiation measurements of the magnetic intensity revealed that severe demagnetization exceeding 85% occurs in Nd 2Fe 14B magnets after only 50 Mrad dose and over 87% for Pr 2Fe 14B after 10 Mrad dose. The annular-shaped Sm 2Co 17 magnets of the FFFTs were almost insensitive to irradiation up to a dose of 2 Grad. Annular-shaped Nd 2Fe 14B magnets also showed resistance to demagnetization, a direct consequence of the annular shape which is characterized by the removal of the stronger demagnetizing field present at the center of a disk-like magnet. As a result, the sensitivity of boron-based permanent magnets to neutron energy (thermal versus fast) was also assessed via specifically designed experiments and discussed.« less

Polished Downhole Transducer Having Improved Signal Coupling

DOEpatents

Hall, David R.; Fox, Joe

2006-03-28

Apparatus and methods to improve signal coupling in downhole inductive transmission elements to reduce the dispersion of magnetic energy at the tool joints and to provide consistent impedance and contact between transmission elements located along the drill string. A transmission element for transmitting information between downhole tools is disclosed in one embodiment of the invention as including an annular core constructed of a magnetically conductive material. The annular core forms an open channel around its circumference and is configured to form a closed channel by mating with a corresponding annular core along an annular mating surface. The mating surface is polished to provide improved magnetic coupling with the corresponding annular core. An annular conductor is disposed within the open channel.

Effect of Permanent Right Internal Mammary Artery Closure on Coronary Collateral Function and Myocardial Ischemia.

PubMed

Stoller, Michael; Seiler, Christian

2017-06-01

The objective of this study is to test the effect of permanent right internal mammary artery device closure on coronary collateral function and myocardial ischemia. This was a prospective, open-label clinical trial in 50 patients with coronary artery disease. The primary study end point was coronary collateral flow index as obtained during a 1-minute proximal right coronary artery (RCA) and left coronary artery balloon occlusion at baseline before and at follow-up examination 6 weeks after distal right internal mammary artery device closure. Collateral flow index is the ratio between simultaneously recorded mean coronary occlusive pressure divided by mean aortic pressure, both subtracted by central venous pressure. Secondary study end points were fractional flow reserve during vessel patency, the quantitative intracoronary ECG ST-segment elevation, and angina pectoris during the same 1-minute coronary occlusion. Collateral flow index in the untreated RCA and left coronary artery changed from 0.071±0.082 at baseline to 0.132±0.117 ( P <0.0001) at follow-up examination and from 0.106±0.092 to 0.081±0.079 ( P =0.29), respectively. RCA fractional flow reserve increased significantly ( P =0.0029) from baseline to follow-up examination, despite deferral of coronary intervention in all patients. There was a decrease in intracoronary ECG ST-elevation during RCA occlusion from baseline to follow-up examination ( P =0.0015); it did not change in the left coronary artery. Angina pectoris during RCA occlusion tended to occur in fewer patients at follow-up versus baseline examination ( P =0.06). Permanent right internal mammary artery device closure seems to augment extracardiac ipsilateral coronary supply to the effect of reducing ischemia in the dependent myocardial region. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02475408. © 2017 The Authors.

Percutaneous closure of the left atrial appendage for prevention of thromboembolism in atrial fibrillation for patients with contraindication to or failure of oral anticoagulation: a single-center experience.

PubMed

Faustino, Ana; Paiva, Luís; Providência, Rui; Trigo, Joana; Botelho, Ana; Costa, Marco; Leitão-Marques, António

2013-06-01

In non-valvular atrial fibrillation 90% of thrombi originate in the left atrial appendage (LAA). Percutaneous LAA closure has been shown to be non-inferior to warfarin for prevention of thromboembolism. To evaluate the initial experience of a single center in percutaneous LAA closure in patients with high thromboembolic risk and in whom oral anticoagulation was impractical or contraindicated or had failed. Patients with non-valvular atrial fibrillation and CHADS2 score ≥2 in whom oral anticoagulation was impractical or contraindicated or had failed underwent percutaneous LAA closure according to the standard technique. After the procedure, dual antiplatelet therapy was maintained for one month, followed by single antiplatelet therapy indefinitely. Patients were followed by clinical assessment and transthoracic and transesophageal echocardiography. The procedure was performed in 22 of the 23 selected patients (95.7%), mean age 70±9 years, CHADS2 score 3.2±0.9 and CHA2DS2-VASC score 4.7±1.4. Intraprocedural device replacement was necessary only in the first patient, due to oversizing. The following periprocedural complications were observed: one femoral pseudoaneurysm, three femoral hematomas and two minor oropharyngeal bleeds, resolved by local hemostatic measures. During a 12±8 month follow-up a mild peri-device flow and a thrombus adhering to the device, resolved under with enoxaparin therapy, were identified. The rate of transient ischemic attack (TIA)/stroke was lower than expected according to the CHADS2 score (0 vs. 6.7±2.2%). In our initial experience, this procedure proved to be a feasible, safe and effective alternative for atrial fibrillation patients in whom oral anticoagulation is not an option. Only relatively minor complications were observed, with a lower than expected TIA/stroke rate. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Cardi-O-Fix duct occluder versus Amplatzer duct occluder for closure of patent ductus arteriosus.

PubMed

Celebi, Ahmet; Demir, Ibrahim Halil; Saritaş, Türkay; Dedeoğlu, Reyhan; Yucel, Ilker Kemal; Demir, Fadli; Erdem, Abdullah

2013-11-15

We sought to investigate the safety, efficacy, and follow-up results of percutaneous patent ductus arteriosus (PDA) closure using the novel Cardi-O-Fix duct occluder (CDO), a device similar to but less expensive than the Amplatzer duct occluder (ADO). We also aimed to compare these two devices in terms of results. Between March 2005 and May 2012, 167 patients diagnosed with moderate-to-large PDA underwent transcatheter closure. ADO was used in 56 (33.5%) patients with a mean age of 8.1 ± 11.9 years (3.6 months-56 years), whereas CDO was used in 111 (66.5%) patients with a mean age of 12.6 ± 14.6 years (4.8 months-63 years). The narrowest PDA diameter, the used device diameter, procedure time, fluoroscopy time, and residual shunt rates were similar between the two groups. Procedural success rate was 100% in both groups. Although the residual shunt rate was higher in the CDO group immediately after the procedure, the difference was not statistically significant (12.6 vs. 8.9%; P = 0.3). There was no statistically significant difference between groups at discharge and during follow-up. No deaths occurred in any of the groups, and there were no differences in complication rates during the short- and mid-term follow-up periods (CDO 7/111 vs. ADO 5/56; P = 0.5 π). The CDO can be used for PDA closure because of its safety, effectiveness, and simplicity in use. It is available in bigger sizes and can be used in patients with large defects. According to our short- and mid-term findings, the results it yields are similar to those of the ADO; thus, it may be the preferred choice owing to its low cost and large size variability. Copyright © 2013 Wiley Periodicals, Inc.

Three cases of subcutaneous granuloma annulare of the penis: a rare presentation of a common disease.

PubMed

Toepfer, Nicholas J; Wessner, Scott R; Elston, Dirk M; Simmons, Jennifer; Sumfest, Joel M

2011-09-01

To describe three patients who presented to a single institution within four years of each other with isolated granuloma annulare of the penis. Granuloma annulare is an inflammatory disease of the dermis that can affect men of any age including childhood. Granuloma annulare of the penis is a remarkably uncommon presentation with only 12 cases previously reported. A retrospective review of pathologic records was conducted confirming three cases of penile granuloma annulare diagnosed at our institution. The three cases are described in detail including the history, presentation, histological findings and treatment of each patient. The clinical variants, characteristic histology, classic clinical presentation, differential diagnosis and recurrence following surgery of granuloma annulare are reviewed. We describe three individuals from a single institution with isolated granuloma annulare of the penis suggesting this condition is more common than previously thought. Patients with penile granuloma annulare may present to practicing urologists and it is important to be familiar with this idiopathic subcutaneous disorder in order to avoid unnecessary aggressive surgery. Copyright © 2011 Elsevier Inc. All rights reserved.

Development of a standardized laparoscopic caecum resection model to simulate laparoscopic appendectomy in rats

PubMed Central

2014-01-01

Background Laparoscopic appendectomy (LA) has become one of the most common surgical procedures to date. To improve and standardize this technique further, cost-effective and reliable animal models are needed. Methods In a pilot study, 30 Wistar rats underwent laparoscopic caecum resection (as rats do not have an appendix vermiformis), to optimize the instrumental and surgical parameters. A subsequent test study was performed in another 30 rats to compare three different techniques for caecum resection and bowel closure. Results Bipolar coagulation led to an insufficiency of caecal stump closure in all operated rats (Group 1, n = 10). Endoloop ligation followed by bipolar coagulation and resection (Group 2, n = 10) or resection with a LigaSure™ device (Group 3, n = 10) resulted in sufficient caecal stump closure. Conclusions We developed a LA model enabling us to compare three different caecum resection techniques in rats. In conclusion, only endoloop closure followed by bipolar coagulation proved to be a secure and cost-effective surgical approach. PMID:24934381

[Resistance to pressure of bronchial closures. Comparison of pressure resistance of manual and stapler bronchial closures depending on the angle to the cartilaginous rings].

PubMed

Ludwig, C; Behrend, M; Hoffarth, U; Schüttler, W; Stoelben, E

2004-09-01

This study was aimed to determine the resistance to pressure of manual and stapled bronchial closures under ideal conditions (90 degrees to the bronchial tree) and parallel to the trachea (45 degrees). An experimental study was done on 60 explanted pig tracheae which were alternatively closed with either double-layer, running sutures angled 90 degrees to the cartilaginous rings or an automatic stapling device. The closure line was placed exactly 90 degrees to the bronchial tree in 30 cases and parallel to the trachea (45 degrees) in 30. The sutures were placed under pressure until air leakage was observed. The leakage pressure was digitally recorded. A statistically significant difference existed between the two groups. Mechanical sutures proved more resistant to pressure (P=0.011). Under ideal conditions, the resistance to pressure of mechanical sutures is equal to if not better than that of manual sutures.

Comparison of Outcomes with Hand-sewn Versus Stapler Closure of Pancreatic Stump in Distal Pancreatectomy.

PubMed

Futagawa, Yasuro; Takano, Yuki; Furukawa, Kenei; Kanehira, Masaru; Onda, Shinji; Sakamoto, Taro; Gocho, Takeshi; Shiba, Hiroaki; Yanaga, Katsuhiko

2017-05-01

The optimal method for pancreatic stump closure to prevent postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP), remains controversial though DP is still the only curative treatment for pancreatic cancer and other malignancies located on pancreatic body or tail. A total of 44 patients who consecutively underwent open DP were retrospectively analyzed, dividing them into two groups: group H (hand-sewn; n=24) and group S (stapler closure; n=20). POPFs were encountered in 5 (21%) and 11 (55%) patients in groups H and S, respectively (p=0.02). POPFs of Clavien-Dindo grade IIIa or above were observed in two (8%) and seven (35%) patients in groups H and S, respectively (p=0.03). When indicating stapler closure, caution should be exercised for pancreatic consistency and thickness, device and cartridge type, and pancreatic duct ligation to more effectively control POPF rates. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Patent ductus arteriosus associated with aberrant right subclavian artery: two cases, one successful interventional closure of PDA.

PubMed

Gomez, Jorge E; Gentile, Jorge I

2011-01-01

Two children were sent to the catheterization laboratory for transcatheter closure of patent ductus arteriosus (PDA). During the intervention, cineangiogram revealed associated aberrant right subclavian artery (ARSA). Both patients had left-sided aortic arch. The first patient was sent to surgery after one unsuccessful attempt to close the PDA due to the proximity of the ARSA and also because of other concomitant cardiac lesions. We successfully treated the second patient by closing the PDA with a Nit-Occlud® PDA occlusion device (Pfm Medical, Carlsbad, California). Similar mirror cases of PDA closure with aberrant left subclavian artery and right aortic arch have been reported. Anatomic features, as well as the technique and management of the procedure, are discussed here.

Left Atrial Appendage Exclusion for Atrial Fibrillation

PubMed Central

Syed, Faisal F.; DeSimone, Christopher V.; Friedman, Paul A.; Asirvatham, Samuel J.

2015-01-01

SYNOPSIS Percutaneous left atrial appendage (LAA) closure is increasingly being used as a treatment strategy to prevent stroke in patients with atrial fibrillation (AF) who have contraindications to anticoagulants. A number of approaches and devices have been developed in the last few years, each with their own unique set of advantages and disadvantages. We review the published studies on surgical and percutaneous approaches to LAA closure; focusing on stroke mechanisms in AF, LAA structure and function relevant to stroke prevention, practical differences in procedural approach, and clinical considerations surrounding management. PMID:25443240

Assessment of Device-Related Thrombus and Associated Clinical Outcomes With the WATCHMAN Left Atrial Appendage Closure Device for Embolic Protection in Patients With Atrial Fibrillation (from the PROTECT-AF Trial).

PubMed

Main, Michael L; Fan, Dali; Reddy, Vivek Y; Holmes, David R; Gordon, Nicole T; Coggins, Tina R; House, John A; Liao, Lawrence; Rabineau, Dawn; Latus, George G; Huber, Kenneth C; Sievert, Horst; Wright, Richard F; Doshi, Shephal K; Douglas, Pamela S

2016-04-01

Left atrial appendage closure with the WATCHMAN device is an alternative to anticoagulation for stroke prevention in selected patients with atrial fibrillation (AF). LA device-related thrombus (DRT) is poorly defined and understood. We aimed to (1) develop consensus echocardiographic diagnostic criteria for DRT; (2) estimate the incidence of DRT; and (3) determine clinical event rates in patients with DRT. In phase 1 (training), a training manual was developed and reviewed by 3 echocardiographers with left atrial appendage closure device experience. All available transesophageal (TEE) studies in the WATCHMAN left atrial appendage system for embolic protection in patients with atrial fibrillation (PROTECT-AF) trial patients with suspected DRT were reviewed in 2 subsequent phases. In phase 2 (primary blind read), each reviewer independently scored each study for DRT, and final echo criteria were developed. Unanimously scored studies were considered adjudicated, whereas all others were reevaluated by all reviewers in phase 3 (group adjudication read). DRT was suspected in 35 of 485 patients by the site investigator, the echocardiography core laboratory, or both; 93 of the individual TEE studies were available for review. In phase 2, 3 readers agreed on 67 (72%) of time points. Based on phases 1 and 2, 5 DRT criteria were developed. In phase 3, studies without agreement in phase 2 were adjudicated using these criteria. Overall, at least 1 TEE was DRT positive in 27 (5.7%) PROTECT-AF patients. Stroke, peripheral embolism, or cardiac/unexplained death occurred in subjects with DRT at a rate of 3.4 per 100 patient-years follow-up. In conclusion, DRT were identified on at least 1 TEE in 27 PROTECT-AF patients, indicating a DRT incidence of 5.7%. Primary efficacy events in patients with DRT occurred at a rate of 3.4 per 100 patient-years follow-up, intermediate in frequency between event rates previously reported for the overall device and warfarin arms in PROTECT-AF. Copyright © 2016 Elsevier Inc. All rights reserved.

Transcatheter pledget-assisted suture tricuspid annuloplasty (PASTA) to create a double-orifice valve.

PubMed

Khan, Jaffar M; Rogers, Toby; Schenke, William H; Greenbaum, Adam B; Babaliaros, Vasilis C; Paone, Gaetano; Ramasawmy, Rajiv; Chen, Marcus Y; Herzka, Daniel A; Lederman, Robert J

2018-02-06

Pledget-assisted suture tricuspid valve annuloplasty (PASTA) is a novel technique using marketed equipment to deliver percutaneous trans-annular sutures to create a double-orifice tricuspid valve. Tricuspid regurgitation is a malignant disease with high surgical mortality and no commercially available transcatheter solution in the US. Two iterations of PASTA were tested using trans-apical or trans-jugular access in swine. Catheters directed paired coronary guidewires to septal and lateral targets on the tricuspid annulus under fluoroscopic and echocardiographic guidance. Guidewires were electrified to traverse the annular targets and exchanged for pledgeted sutures. The sutures were drawn together and knotted, apposing septal and lateral targets, creating a double orifice tricuspid valve. Twenty-two pigs underwent PASTA. Annular and chamber dimensions were reduced (annular area, 10.1 ± 0.8 cm 2 to 3.8 ± 1.5 cm 2 (naïve) and 13.1 ± 1.5 cm 2 to 6.2 ± 1.0 cm 2 (diseased); septal-lateral diameter, 3.9 ± 0.3 mm to 1.4 ± 0.6 mm (naïve) and 4.4 ± 0.4 mm to 1.7 ± 1.0 mm (diseased); and right ventricular end-diastolic volume, 94 ± 13 ml to 85 ± 14 ml (naïve) and 157 ± 25 ml to 143 ± 20 ml (diseased)). MRI derived tricuspid regurgitation fraction fell from 32 ± 12% to 4 ± 5%. Results were sustained at 30 days. Pledget pull-through force was five-fold higher (40.6 ± 11.7N vs 8.0 ± 2.6N, P < .01) using this strategy compared to single puncture techniques used to anchor current investigational devices. Serious complications were related to apical access. PASTA reduces annular dimensions and tricuspid regurgitation in pigs. It may be cautiously applied to selected patients with severe tricuspid regurgitation and no options. This is the first transcatheter procedure, to our knowledge, to deliver standard pledgeted sutures to repair cardiac pathology. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Development of computer-aided design system of elastic sensitive elements of automatic metering devices

NASA Astrophysics Data System (ADS)

Kalinkina, M. E.; Kozlov, A. S.; Labkovskaia, R. I.; Pirozhnikova, O. I.; Tkalich, V. L.; Shmakov, N. A.

2018-05-01

The object of research is the element base of devices of control and automation systems, including in its composition annular elastic sensitive elements, methods of their modeling, calculation algorithms and software complexes for automation of their design processes. The article is devoted to the development of the computer-aided design system of elastic sensitive elements used in weight- and force-measuring automation devices. Based on the mathematical modeling of deformation processes in a solid, as well as the results of static and dynamic analysis, the calculation of elastic elements is given using the capabilities of modern software systems based on numerical simulation. In the course of the simulation, the model was a divided hexagonal grid of finite elements with a maximum size not exceeding 2.5 mm. The results of modal and dynamic analysis are presented in this article.

Formation of high-order acoustic Bessel beams by spiral diffraction gratings

NASA Astrophysics Data System (ADS)

Jiménez, Noé; Picó, R.; Sánchez-Morcillo, V.; Romero-García, V.; García-Raffi, L. M.; Staliunas, K.

2016-11-01

The formation of high-order Bessel beams by a passive acoustic device consisting of an Archimedes' spiral diffraction grating is theoretically, numerically, and experimentally reported in this paper. These beams are propagation-invariant solutions of the Helmholtz equation and are characterized by an azimuthal variation of the phase along its annular spectrum producing an acoustic vortex in the near field. In our system, the scattering of plane acoustic waves by the spiral grating leads to the formation of the acoustic vortex with zero pressure on axis and the angular phase dislocations characterized by the spiral geometry. The order of the generated Bessel beam and, as a consequence, the size of the generated vortex can be fixed by the number of arms in the spiral diffraction grating. The obtained results allow for obtaining Bessel beams with controllable vorticity by a passive device, which has potential applications in low-cost acoustic tweezers and acoustic radiation force devices.

Modeling of combined effects of divertor closure and advanced magnetic configuration on detachment in DIII-D by SOLPS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Si, Hang; Guo, Houyang Y.; Covele, Brent

One of the major challenges facing the design and operation of next-step high-power steady-state fusion devices is to develop a divertor solution for handling power exhaust, while ensuring acceptable divertor target plate erosion, which necessitates access to divertor detachment at relative low main plasma densities compatible with current drive and high plasma confinement. Detailed modeling with SOLPS is carried out to examine the effect of divertor closure on detachment with the normal single null divertor (SD) configuration, as well as one of the advanced divertor configurations, such as x-divertor (XD) respectively. The SOLPS modeling for a high confinement plasma in DIII-D finds that increasing divertor closure with SD reduces the upstream separatrix density at the onset of detachment frommore » $$1.18\\times {{10}^{19}}\\,{{{\\rm m}}^{-3}}$$ to $$0.88\\times {{10}^{19}}\\,{{{\\rm m}}^{-3}}$$. Furthermore, coupling the divertor closure with XD further promotes the onset of divertor detachment at a still lower upstream separatrix density, down to the value of $$0.67\\times {{10}^{19}}\\,{{{\\rm m}}^{-3}}$$, thus, showing that divertor closure and advanced magnetic configuration can work synergistically to facilitate divertor detachment.« less

Modeling of combined effects of divertor closure and advanced magnetic configuration on detachment in DIII-D by SOLPS

DOE PAGES

Si, Hang; Guo, Houyang Y.; Covele, Brent; ...

2018-04-04

One of the major challenges facing the design and operation of next-step high-power steady-state fusion devices is to develop a divertor solution for handling power exhaust, while ensuring acceptable divertor target plate erosion, which necessitates access to divertor detachment at relative low main plasma densities compatible with current drive and high plasma confinement. Detailed modeling with SOLPS is carried out to examine the effect of divertor closure on detachment with the normal single null divertor (SD) configuration, as well as one of the advanced divertor configurations, such as x-divertor (XD) respectively. The SOLPS modeling for a high confinement plasma in DIII-D finds that increasing divertor closure with SD reduces the upstream separatrix density at the onset of detachment frommore » $$1.18\\times {{10}^{19}}\\,{{{\\rm m}}^{-3}}$$ to $$0.88\\times {{10}^{19}}\\,{{{\\rm m}}^{-3}}$$. Furthermore, coupling the divertor closure with XD further promotes the onset of divertor detachment at a still lower upstream separatrix density, down to the value of $$0.67\\times {{10}^{19}}\\,{{{\\rm m}}^{-3}}$$, thus, showing that divertor closure and advanced magnetic configuration can work synergistically to facilitate divertor detachment.« less

Simple Skin-Stretching Device in Assisted Tension-Free Wound Closure.

PubMed

Cheng, Li-Fu; Lee, Jiunn-Tat; Hsu, Honda; Wu, Meng-Si

2017-03-01

Numerous conventional wound reconstruction methods, such as wound undermining with direct suture, skin graft, and flap surgery, can be used to treat large wounds. The adequate undermining of the skin flaps of a wound is a commonly used technique for achieving the closure of large tension wounds; however, the use of tension to approximate and suture the skin flaps can cause ischemic marginal necrosis. The purpose of this study is to use elastic rubber bands to relieve the tension of direct wound closure for simultaneously minimizing the risks of wound dehiscence and wound edge ischemia that lead to necrosis. This retrospective study was conducted to evaluate our clinical experiences with 22 large wounds, which involved performing primary closures under a considerable amount of tension by using elastic rubber bands in a skin-stretching technique after a wide undermining procedure. Assessment of the results entailed complete wound healing and related complications. All 22 wounds in our study showed fair to good results except for one. The mean success rate was approximately 95.45%. The simple skin-stretching design enabled tension-free skin closure, which pulled the bilateral undermining skin flaps as bilateral fasciocutaneous advancement flaps. The skin-stretching technique was generally successful.

Modeling of combined effects of divertor closure and advanced magnetic configuration on detachment in DIII-D by SOLPS

NASA Astrophysics Data System (ADS)

Si, H.; Guo, H. Y.; Covele, B.; Leonard, A. W.; Watkins, J. G.; Thomas, D.; Ding, R.

2018-05-01

One of the major challenges facing the design and operation of next-step high-power steady-state fusion devices is to develop a divertor solution for handling power exhaust, while ensuring acceptable divertor target plate erosion, which necessitates access to divertor detachment at relative low main plasma densities compatible with current drive and high plasma confinement. Detailed modeling with SOLPS is carried out to examine the effect of divertor closure on detachment with the normal single null divertor (SD) configuration, as well as one of the advanced divertor configurations, such as x-divertor (XD) respectively. The SOLPS modeling for a high confinement plasma in DIII-D finds that increasing divertor closure with SD reduces the upstream separatrix density at the onset of detachment from 1.18× {{10}19} {{m}-3} to 0.88× {{10}19} {{m}-3} . Moreover, coupling the divertor closure with XD further promotes the onset of divertor detachment at a still lower upstream separatrix density, down to the value of 0.67× {{10}19} {{m}-3} , thus, showing that divertor closure and advanced magnetic configuration can work synergistically to facilitate divertor detachment.

Comparison of anchorage reinforcement with temporary anchorage devices or a Herbst appliance during lingual orthodontic protraction of mandibular molars without maxillary counterbalance extraction.

PubMed

Metzner, Rebecca; Schwestka-Polly, Rainer; Helms, Hans-Joachim; Wiechmann, Dirk

2015-06-20

Orthodontic protraction of mandibular molars without maxillary counterbalance extraction in cases of aplasia or extraction requires stable anchorage. Reinforcement may be achieved by using either temporary anchorage devices (TAD) or a fixed, functional appliance. The objective was to compare the clinical effectiveness of both methods by testing the null-hypothesis of no significant difference in velocity of space closure (in mm/month) between them. In addition, we set out to describe the quality of posterior space management and treatment-related factors, such as loss of anchorage (assessed in terms of proportions of gap closure by posterior protraction or anterior retraction), frequencies of incomplete space closure, and potential improvement in the sagittal canine relationship. Twenty-seven subjects (15 male/12 female) with a total of 36 sites treated with a lingual multi-bracket appliance were available for retrospective evaluation of the effects of anchorage reinforcement achieved with either a Herbst appliance (n(subjects) = 15; 7 both-sided/8 single-sided Herbst appliances; n(sites) = 22) or TADs (n(subjects )= 12; 2 both-sided; 10 single-sided; n(sites) = 14). Descriptive analysis was based on measurements using intra-oral photographs which were individually scaled to corresponding plaster casts and taken on insertion of anchorage mechanics (T1), following removal of anchorage mechanics (T2), and at the end of multi-bracket treatment (T3). The null-hypothesis was rejected: The rate of mean molar protraction was significantly faster in the Herbst-reinforced group (0.51 mm/month) than in the TAD group (0.35). While complete space closure by sheer protraction of posterior teeth was achieved in all Herbst-treated cases, space closure in the TAD group was achieved in 76.9% of subjects by sheer protraction of molars, and it was incomplete in 50% of cases (mean gap residues: 1 mm). Whilst there was a deterioration in the canine relationship towards Angle-Class II malocclusion in 57.14% of space closure sites in TAD-treated subjects (indicating a loss of anchorage), an improvement in canine occlusion was observed in 90.9% of Herbst-treated cases. Subjects requiring rapid space closure by molar protraction in combination with a correction of distal occlusion may benefit from using Herbst appliances for anterior segment anchorage reinforcement rather than TAD anchorage.

Barbed suture material technique for wound closure and concomitant tube placement in uniportal VATS for pneumothorax

PubMed Central

2017-01-01

Background Uniportal video-assisted thoracoscopic surgery (VATS) is an alternative modality for treatment of primary spontaneous pneumothorax (PSP) with its less invasiveness and acceptable surgical outcomes. However, a few reports have been introduced for wound management to achieve better cosmetic wound healing and for placement of the chest tube in uniportal VATS. Thus, we aimed to evaluate the feasibility of our novel method for wound closure and concomitant tube placement using continuous barbed suture material in uniportal VATS for PSP. Methods Between July 2012 and December 2015, consecutive 31 patients (22 males) underwent uniportal VATS to treat PSP. Bilateral approaches were performed in four patients, thus total 35 cases were enrolled. We divided them into two groups with one group of 17 (48.5%) cases (group A), using barbed absorbable wound closure device for knotless continuous wound closure and subsequent chest tube anchoring, and the other group of 18 (51.4%) cases (group B), using conventional suture anchoring after skin closure using absorbable suture device. Postoperative surgical outcomes were compared to assess the feasibility of this technique. Results Demographic data demonstrate no significant difference in both groups. There was no significant difference in length of hospital stay (3.7±1.2 vs. 4.1±1.2 days, P=0.267) and in median chest tube indwelling time (2.4±0.9 vs. 3.1±1.2 days, P=0.066), respectively. Operation time in group A was shorter than in group B but there was no significant difference (41.7±11.8 vs. 45.6±16.0 minutes, P=0.415). There was neither conversion to two or three port VATS in all cases. In group A, all chest tubes were removed with concomitant sealing the tube removal site by pulling the thread. Residual knots do not exist that stitch out procedure is not required. There was no wound complication in both groups during the median follow-up period of 18 months. Conclusions Knotless, barbed suture material technique for continuous wound closure with concomitant chest tube placement achieved equivocal outcomes in comparison to the conventional suture anchoring method. We suggest this simple technique for wound closure and easy tube removal with cosmetic wound healing in uniportal VATS for PSP. PMID:28616277

Annular pancreas

MedlinePlus

... page: //medlineplus.gov/ency/article/001142.htm Annular pancreas To use the sharing features on this page, please enable JavaScript. An annular pancreas is a ring of pancreatic tissue that encircles ...

The immediate use of a silicone sheet wound closure device in scar reduction and prevention.

PubMed

Parry, James R; Stupak, Howard D; Johnson, Calvin M

2016-02-01

Silicone has been used successfully postoperatively in the prevention of hypertrophic and other types of adverse scars. The Silicone Suture Plate (SSP) is a new, minimally invasive, sterile wound closure device that is applied intraoperatively to prevent adverse scarring. The SSP device permits immediate application of silicone while concurrently allowing for wound-edge tension redistribution. In this prospective, controlled, single-blinded clinical study, 8 consecutive patients undergoing deep-plane rhytidectomy were selected. SSP devices were placed on the patients' posterior rhytidectomy hairline incision; the mirror-image control site underwent standard suturing techniques. Three blinded, independent raters assessed the treatment and control sides at 6-week and 4-month follow-up visits, using the Objective Scar Assessment Scale (OSAS), a validated scar assessment tool. The 6-week OSAS scores revealed an 18.4% improvement on the side with the SSP device (13.3) when compared to the control side (16.3). The 4-month OSAS scores showed a 27.3% improvement on the treatment side from 12.7 (control) to 9.2 (SSP). These OSAS results were found to be statistically significant when taken as an aggregate of the observers' scores, but not when observers' scores were measured individually (p < 0.05). In our series of patients, we showed promising results with the use of the SSP device. Early silicone application and tissue tension distribution contributed to an overall more aesthetically pleasing scar compared to those seen with standard suturing techniques, although more testing is required.

40 CFR 63.961 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission... air emissions to the atmosphere by blocking an opening to the individual drain system. Closure devices...

Performance Assessment of Bi-Directional Knotless Tissue-Closure Devices in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters, 2009 - Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodley, Christa M.; Wagner, Katie A.; Bryson, Amanda J.

2012-11-09

The purpose of this report is to assess the performance of bi-directional knotless tissue-closure devices for use in tagging juvenile salmon. This study is part of an ongoing effort at Pacific Northwest National Laboratory (PNNL) to reduce unwanted effects of tags and tagging procedures on the survival and behavior of juvenile salmonids, by assessing and refining suturing techniques, suture materials, and tag burdens. The objective of this study was to compare the performance of the knotless (barbed) suture, using three different suture patterns (treatments: 6-point, Wide “N”, Wide “N” Knot), to the current method of suturing (MonocrylTM monofilament, discontinuous suturesmore » with a 2×2×2×2 knot) used in monitoring and research programs with a novel antiseptic barrier on the wound (“Second Skin”).« less

Percutaneous intracardiac beating-heart surgery using metal MEMS tissue approximation tools

PubMed Central

Gosline, Andrew H; Vasilyev, Nikolay V; Butler, Evan J; Folk, Chris; Cohen, Adam; Chen, Rich; Lang, Nora; del Nido, Pedro J; Dupont, Pierre E

2013-01-01

Achieving superior outcomes through the use of robots in medical applications requires an integrated approach to the design of the robot, tooling and the procedure itself. In this paper, this approach is applied to develop a robotic technique for closing abnormal communication between the atria of the heart. The goal is to achieve the efficacy of surgical closure as performed on a stopped, open heart with the reduced risk and trauma of a beating-heart catheter-based procedure. In the proposed approach, a concentric tube robot is used to percutaneously access the right atrium and deploy a tissue approximation device. The device is constructed using a metal microelectromechanical system (MEMS) fabrication process and is designed to both fit the manipulation capabilities of the robot as well as to reproduce the beneficial features of surgical closure by suture. The effectiveness of the approach is demonstrated through ex vivo and in vivo experiments. PMID:23750066

Transatrial Intrapericardial Tricuspid Annuloplasty

PubMed Central

Rogers, Toby; Ratnayaka, Kanishka; Sonmez, Merdim; Franson, Dominique N.; Schenke, William H.; Mazal, Jonathan R.; Kocaturk, Ozgur; Chen, Marcus Y.; Faranesh, Anthony Z.; Lederman, Robert J.

2015-01-01

OBJECTIVES This study sought to demonstrate transcatheter deployment of a circumferential device within the pericardial space to modify tricuspid annular dimensions interactively and to reduce functional tricuspid regurgitation (TR) in swine. BACKGROUND Functional TR is common and is associated with increased morbidity and mortality. There are no reported transcatheter tricuspid valve repairs. We describe a transcatheter extracardiac tricuspid annuloplasty device positioned in the pericardial space and delivered by puncture through the right atrial appendage. We demonstrate acute and chronic feasibility in swine. METHODS Transatrial intrapericardial tricuspid annuloplasty (TRAIPTA) was performed in 16 Yorkshire swine, including 4 with functional TR. Invasive hemodynamics and cardiac magnetic resonance imaging (MRI) were performed at baseline, immediately after annuloplasty and at follow-up. RESULTS Pericardial access via a right atrial appendage puncture was uncomplicated. In 9 naïve animals, tricuspid septal-lateral and anteroposterior dimensions, the annular area and perimeter, were reduced by 49%, 31%, 59%, and 24% (p < 0.001), respectively. Tricuspid leaflet coaptation length was increased by 53% (p < 0.001). Tricuspid geometric changes were maintained after 9.7 days (range, 7 to 14 days). Small effusions (mean, 46 ml) were observed immediately post-procedure but resolved completely at follow-up. In 4 animals with functional TR, severity of regurgitation by intracardiac echocardiography was reduced. CONCLUSIONS Transatrial intrapericardial tricuspid annuloplasty is a transcatheter extracardiac tricuspid valve repair performed by exiting the heart from within via a transatrial puncture. The geometry of the tricuspid annulus can interactively be modified to reduce severity of functional TR in an animal model. PMID:25703872

Percutaneous left atrial appendage closure vs warfarin for atrial fibrillation: a randomized clinical trial.

PubMed

Reddy, Vivek Y; Sievert, Horst; Halperin, Jonathan; Doshi, Shephal K; Buchbinder, Maurice; Neuzil, Petr; Huber, Kenneth; Whisenant, Brian; Kar, Saibal; Swarup, Vijay; Gordon, Nicole; Holmes, David

2014-11-19

While effective in preventing stroke in patients with atrial fibrillation (AF), warfarin is limited by a narrow therapeutic profile, a need for lifelong coagulation monitoring, and multiple drug and diet interactions. To determine whether a local strategy of mechanical left atrial appendage (LAA) closure was noninferior to warfarin. PROTECT AF was a multicenter, randomized (2:1), unblinded, Bayesian-designed study conducted at 59 hospitals of 707 patients with nonvalvular AF and at least 1 additional stroke risk factor (CHADS2 score ≥1). Enrollment occurred between February 2005 and June 2008 and included 4-year follow-up through October 2012. Noninferiority required a posterior probability greater than 97.5% and superiority a probability of 95% or greater; the noninferiority margin was a rate ratio of 2.0 comparing event rates between treatment groups. Left atrial appendage closure with the device (n = 463) or warfarin (n = 244; target international normalized ratio, 2-3). A composite efficacy end point including stroke, systemic embolism, and cardiovascular/unexplained death, analyzed by intention-to-treat. At a mean (SD) follow-up of 3.8 (1.7) years (2621 patient-years), there were 39 events among 463 patients (8.4%) in the device group for a primary event rate of 2.3 events per 100 patient-years, compared with 34 events among 244 patients (13.9%) for a primary event rate of 3.8 events per 100 patient-years with warfarin (rate ratio, 0.60; 95% credible interval, 0.41-1.05), meeting prespecified criteria for both noninferiority (posterior probability, >99.9%) and superiority (posterior probability, 96.0%). Patients in the device group demonstrated lower rates of both cardiovascular mortality (1.0 events per 100 patient-years for the device group [17/463 patients, 3.7%] vs 2.4 events per 100 patient-years with warfarin [22/244 patients, 9.0%]; hazard ratio [HR], 0.40; 95% CI, 0.21-0.75; P = .005) and all-cause mortality (3.2 events per 100 patient-years for the device group [57/466 patients, 12.3%] vs 4.8 events per 100 patient-years with warfarin [44/244 patients, 18.0%]; HR, 0.66; 95% CI, 0.45-0.98; P = .04). After 3.8 years of follow-up among patients with nonvalvular AF at elevated risk for stroke, percutaneous LAA closure met criteria for both noninferiority and superiority, compared with warfarin, for preventing the combined outcome of stroke, systemic embolism, and cardiovascular death, as well as superiority for cardiovascular and all-cause mortality. clinicaltrials.gov Identifier: NCT00129545.

Transcatheter closure of hemodynamic significant patent ductus arteriosus in 32 premature infants by amplatzer ductal occluder additional size-ADOIIAS.

PubMed

Morville, Patrice; Akhavi, Ahmad

2017-10-01

The advent of Amplatzer Duct Occluder II additional Size (ADOIIAS) provided the potential to close hemodynamic significant patent ductus arteriosus (HSPDA) and to analyze the feasibility, safety and efficacy of the device. Treatment of a patent ductus arteriosus (PDA) in very premature neonates is still a dilemma for the neonatalogist who has to consider its significance and has to choose among different treatment options. Because surgical ligation and medical therapy both have their drawbacks, interventional catheterization might provide an alternative means of closing HSPDA. Between September 2013 and June 2015, 32 premature infants with complications related to HSPDA defined by ultrasound (US) underwent transcatheter closure. The procedure was performed in the catheterization laboratory by venous cannulation without angiography. The position of the occluder was directed by X-ray and US. In particular we looked at procedural details, device size selection, complications, and short and mid-term outcomes. Thirty two premature infants, all of whom had clinical complications related to HSPDA, born at gestational ages ranging between 23.6 and 36 weeks (mean ± standard deviation 28 ± 3 weeks) underwent attempted transcatheter PDA closure using the ADOIIAS. Their mean age and weight at the time of procedure was 25 days (range 8-70 days) and 1373 g (range 680-2480 g), respectively. Ten infants weighed ≤1,000g. All ducts were tubular. The mean PDA and device waist diameters were 3.2 ± 0.6mm (range 2.2-4) and 4.4 ± 0.6 mm, respectively, and the mean PDA and device lengths 5.2 ± 2.0 mm (range 2-10) and 3.4 ± 1.3 mm. Median fluoroscopy and procedural times were 11 min (range 3-24) and 28 min (range 10-90), respectively. Complete closure was achieved in all but one patient. There was no device migration. A left pulmonary artery (LPA) obstruction developed in one patient. Five infants died. Four deaths were related to complications of prematurity and one death in a 680 g infant was related to the procedure. It is feasible to close HSPDA in relative safety in premature infants who have severe and complex disease. Success requires perfect selection of the occluder and exact positioning by US. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Prevalence of patent foramen ovale and usefulness of percutaneous closure device in carcinoid heart disease.

PubMed

Mansencal, Nicolas; Mitry, Emmanuel; Pillière, Rémy; Lepère, Céline; Gérardin, Benoît; Petit, Jérôme; Gandjbakhch, Iradj; Rougier, Philippe; Dubourg, Olivier

2008-04-01

The aim of this study was to assess (1) the incidence of patent foramen ovale (PFO) in carcinoid syndrome (CS) and (2) the feasibility of percutaneous closure procedure in selected patients with CS. One hundred eight patients were prospectively studied: 54 with CS and an age- and gender-matched control group. All patients underwent conventional and contrast echocardiography. Patients with clinical signs of dyspnea (New York Heart Association class > or =III), cyanosis, carcinoid heart disease (CHD), and severe PFO were referred for the percutaneous closure of PFO. The prevalence of PFO was 41% in patients with CS and 22% in the control group (p = 0.03) and was significantly higher in patients with CHD (59%, p = 0.009). Four patients (14% of those with CHD) were referred for the percutaneous closure of PFO, and 3 patients ultimately underwent PFO closure (using Amplatzer septal occluders). At 6-month follow-up, New York Heart Association class was improved in all patients, as well as arterial blood gas results (p = 0.04) and 6-minute walking distance (p = 0.03), but all patients presented residual right-to-left shunts. In conclusion, this prospective study demonstrates that in patients with CHD, the prevalence of PFO is high and that percutaneous closure of PFO is feasible, with a reduction in symptoms but with residual shunting.

Left atrial appendage closure: a new technique for clinical practice.

PubMed

John Camm, A; Colombo, Antonio; Corbucci, Giorgio; Padeletti, Luigi

2014-03-01

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. It is associated with increased risk for stroke mainly due to cardiac embolism from the left atrial appendage (LAA). Occlusion of the LAA by means of a device represents a valid alternative to oral anticoagulation, mainly in patients who cannot tolerate this therapy because of a high bleeding risk. Recent data on the endocardial device WATCHMAN show encouraging results for this patient population in terms of stroke risk reduction compared to the expected rate as well as in terms of implant success. This article reviews all relevant publications related to the main surgical and transcatheter devices used for LAA closure (LAAC). PROTECT-AF, the first prospective randomized trial conducted on this technique, showed that LAA occlusion using the WATCHMAN was noninferior to warfarin for a combined end-point in patients with nonvalvular AF. There is a lack of large-scale randomized trials on long-term stroke risk in patients submitted to LAAC. Most studies are relatively small and focus on the comparison of different surgical techniques with regard to complete/incomplete closure success. More recently, PROTECT-AF long-term results (4-year follow-up) demonstrated that LAAC was statistically superior to warfarin in terms of efficacy. This review concludes that it is now appropriate to consider these techniques for patients with AF who are at high risk for stroke for whom effective conventional or novel anticoagulant therapy is not available or who present problems in managing drug treatment. Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Telephoto axicon

NASA Astrophysics Data System (ADS)

Burvall, Anna; Goncharov, Alexander; Dainty, Chris

2005-09-01

The axicon is an optical element which creates a narrow focal line along the optical axis, unlike the single focal point produced by a lens. The long and precisely defined axicon focal line is used e.g. in alignment, or to extend the depth of focus of existing methods such as optical coherence tomography or light sectioning. Axicons are generally manufactured as refractive cones or diffractive circular gratings. They are also made as lens systems or doublet lenses, which are easier to produce. We present a design in the form of a reflective-refractive single-element device with annular aperture. This very compact system has only two surfaces, which can be spherical or aspheric depending on the quality required of the focal line. Both surfaces have reflective coatings at specific zones, providing an annular beam suitable for generating extended focal lines. One draw-back of a normal axicon is its sensitivity to the angle of illumination. Even for relatively small angles, astigmatism will broaden the focus and give it an asteroid shape. For our design, with spherical surfaces concentric about the center of the entrance pupil, the focal line remains unchanged in off-axis illumination.

Missing LINQ: extrusion of a new-generation implantable loop recorder in a child.

PubMed

Chaouki, Ahmad S; Czosek, Richard J; Spar, David S

2016-10-01

Cardiac rhythm monitoring has been facilitated by the use of implantable loop recorders. New models of these devices are 87% smaller than before allowing for easier implantation and use in the paediatric population. Recommendations are for closure with adhesive. We report a device extrusion in a 6-year-old patient. Based on this, our practice has changed to include subcutaneous sutures this complication.

40 CFR 63.5150 - If I use a control device to comply with the emission standards, what monitoring must I do?

Code of Federal Regulations, 2010 CFR

2010-07-01

... line that could divert the exhaust stream away from the control device to the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal... thermocouple or temperature sensor in the combustion chamber at a location in the combustion zone. (iii) For a...

40 CFR 63.5150 - If I use a control device to comply with the emission standards, what monitoring must I do?

Code of Federal Regulations, 2011 CFR

2011-07-01

... line that could divert the exhaust stream away from the control device to the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal... thermocouple or temperature sensor in the combustion chamber at a location in the combustion zone. (iii) For a...

Percutaneous Patent Ductus Arteriosus (PDA) Closure in Very Preterm Infants: Feasibility and Complications.

PubMed

Backes, Carl H; Cheatham, Sharon L; Deyo, Grace M; Leopold, Scott; Ball, Molly K; Smith, Charles V; Garg, Vidu; Holzer, Ralf J; Cheatham, John P; Berman, Darren P

2016-02-12

Percutaneous closure of patent ductus arteriosus (PDA) in term neonates is established, but data regarding outcomes in infants born very preterm (<32 weeks of gestation) are minimal, and no published criteria exist establishing a minimal weight of 4 kg as a suitable cutoff. We sought to analyze outcomes of percutaneous PDA occlusion in infants born very preterm and referred for PDA closure at weights <4 kg. Retrospective analysis (January 2005-January 2014) was done at a single pediatric center. Procedural successes and adverse events were recorded. Markers of respiratory status (need for mechanical ventilation) were determined, with comparisons made before and after catheterization. A total of 52 very preterm infants with a median procedural weight of 2.9 kg (range 1.2-3.9 kg) underwent attempted PDA closure. Twenty-five percent (13/52) of infants were <2.5 kg. Successful device placement was achieved in 46/52 (88%) of infants. An adverse event occurred in 33% of cases, with an acute arterial injury the most common complication. We observed no association between weight at time of procedure and the risk of an adverse event. No deaths were attributable to the PDA closure. Compared to precatheterization trends, percutaneous PDA closure resulted in improved respiratory status, including less exposure to mechanical ventilation (mixed effects logistic model, P<0.01). Among infants born very preterm, percutaneous PDA closure at weights <4 kg is generally safe and may improve respiratory health, but risk of arterial injury is noteworthy. Randomized clinical trials are needed to assess clinically relevant differences in outcomes following percutaneous PDA closure versus alternative (surgical ligation) management strategies. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Variation in practice patterns in device closure of atrial septal defects and patent ductus arteriosus: An analysis of data from the IMproving Pediatric and Adult Congenital Treatment (IMPACT) registry.

PubMed

O'Byrne, Michael L; Kennedy, Kevin F; Rome, Jonathan J; Glatz, Andrew C

2018-02-01

Practice variation is a potentially important measure of healthcare quality. The IMPACT registry provides a representative national sample with which to study practice variation in trans-catheter interventions for congenital heart disease. We studied cases for closure of atrial septal defect (ASD) and patent ductus arteriosus (PDA) in IMPACT between January 1, 2011, and September 30, 2015, using hierarchical multivariate models studying (1) the distribution of indications for closure and (2) in patients whose indication for closure was left (LVVO) or right ventricular volume overload (RVVO), the factors influencing probability of closure of a small defect (either in size or in terms of the magnitude of shunt). Over the study period, 5233 PDA and 4459 ASD cases were performed at 77 hospitals. The indications for ASD closure were RVVO in 84% and stroke prevention in 13%. Indications for PDA closure were LVVO in 57%, endocarditis prevention in 36%, and pulmonary hypertension in 7%. There was statistically significant variability in indications between hospitals for PDA and ASD procedures (median rate ratio (MRR): 1.3 and 1.1; both P<.001). The proportion of cases for volume overload with a Qp:Qs <1.5:1 decreased with increasing PDA and ASD procedural volume (P=.04 and 0.05). For ASD, the proportion was higher at hospitals with a larger proportion of adult cases (P=.0007). There was significant variation in practice in the risk of closing PDA <2 mm for LVVO (MRR: 1.4, P<.001). There is measurable variation in transcatheter closure of PDA and ASD. Further research is necessary to study whether this affects outcomes or resource utilization. Copyright © 2017 Elsevier Inc. All rights reserved.

Vascular Closure Devices in Interventional Radiology Practice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patel, Rafiuddin, E-mail: rafiuddin.patel@ouh.nhs.uk; Muller-Hulsbeck, Stefan, E-mail: muehue@diako.de; Morgan, Robert, E-mail: robert.morgan@stgeorges.nhs.uk

2015-08-15

Manual compression (MC) is a well-established technique for haemostasis following percutaneous arterial intervention. However, MC is labour and time intensive with potential limitations, particularly for patients who are coagulopathic, unable to comply with bed rest or obese and when large sheaths or anti-coagulants are used. There are a variety of vascular closure devices (VCDs) available to overcome these limitations. This review gives an overview of current VCDs, their mechanism of action, individual strengths and weaknesses, evidence base and utility in interventional radiology (IR) practice. The majority of the published evidence on VCDs is derived from patients undergoing cardiac interventions, whichmore » should be borne in mind when considering the applicability and transfer of this data for general IR practice. Overall, the evidence suggests that most VCDs are effective in achieving haemostasis with a similar rate of complications to MC although the complication profile associated with VCDs is distinct to that of MC. There is insufficient evidence to comparatively analyse the different types of VCDs currently available or reliably judge their cost-effectiveness. The interventional radiologist should have a thorough understanding of the available techniques for haemostasis and be able to identify and utilise the most appropriate strategy and closure technique for the individual patient.« less

Periprocedural intracardiac echocardiography for left atrial appendage closure: a dual-center experience.

PubMed

Berti, Sergio; Paradossi, Umberto; Meucci, Francesco; Trianni, Giuseppe; Tzikas, Apostolos; Rezzaghi, Marco; Stolkova, Miroslava; Palmieri, Cataldo; Mori, Fabio; Santoro, Gennaro

2014-09-01

This dual-center study sought to demonstrate the utility and safety of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to transesophageal echocardiography (TEE) during Amplatzer Cardiac Plug device implantation. Over 90% of intracardiac thrombi in atrial fibrillation originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA percutaneous occlusion. TEE is typically used to guide implantation. ICE-guided percutaneous LAA closure was performed in 121 patients to evaluate the following tasks typically achieved by TEE: assessment of the LAA dimension for device sizing; guidance of transseptal puncture; verification of the delivery sheath position; confirmation of location and stability of the device before and after release and continuous monitoring to detect procedural complications. In 51 consecutive patients, we compared the measurements obtained by ICE and fluoroscopy to choose the size of the device. The device was successfully implanted in 117 patients, yielding a technical success rate of 96.7%. Procedural success was achieved in 113 cases (93.4%). Four major adverse events (3 cardiac tamponades and 1 in-hospital transient ischemic attack) occurred. There was significant correlation in the measurements for device sizing assessed by angiography and ICE (r = 0.94, p < 0.0001). ICE imaging was able to perform the tasks typically provided by TEE during implantation of the Amplatzer Cardiac Plug device for LAA occlusion. Therefore, we provide evidence that the use of ICE offered accurate measurements of LAA dimension in order to select the correct device sizes. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Transcatheter closure of calcified patent ductus arteriosus in older adult patients: Immediate and 12-month follow-up results.

PubMed

Gu, Xinghua; Zhang, Qiuwang; Sun, Hourong; Fei, Jianchun; Zhang, Xiquan; Kutryk, Michael J

2017-05-01

To present our experience in transcatheter closure of calcified patent ductus arteriosus (PDA) in older adult patients, which has rarely been reported. From 2009 to 2014, a total of 16 patients (median age 58 years) with calcified PDA underwent transcatheter closure in our center. All patients were symptomatic with major symptoms being exertional dyspnea (in 12), palpitations (in 8), and fatigue (in 5). A continuous murmur was heard in all patients. The median ductus diameter was 4 mm (range 3-7 mm). The median Qp/Qs was 1.6 (range 1.4-2.9). Transcatheter closure was performed for all patients. The size of the occluder selected was 2-3 mm greater than the narrowest portion of PDA. We experienced difficulties in advancing the multipurpose catheter through the calcified duct in about one third of patients (5/16). Considering that calcified tissue has a greater tendency to rupture, hence, to close PDA in these patients, they adopted the retrograde wire-assisted technique and modified the procedure to reduce the shear stress of sheath and avoid any sheath kinking. For the remaining 11 patients, the advancement of the multipurpose catheter through the calcified duct was smooth and the conventional antegrade approach was applied. Clinical examination, standard 12-lead electrocardiography, chest x-ray, and transthoracic echocardiography were performed before hospital discharge, at 1-, 3-, 6-, and 12-months follow-ups. All PDAs were successfully closed. There were no deaths. Three patients had a trivial residual shunt, with one also having intravascular hemolysis. Following pharmacological treatment, hemolysis signs vanished at 7 days postprocedure. The trivial residual shunt disappeared in all three patients at 3-month follow-up. No new-onset residual shunt, device embolization, device dislocation, infective endocarditis, or embolism was observed at all follow-up time points. Successful closure of calcified PDA with few complications in older adult patients was achieved using the duct occluder. © 2016 Wiley Periodicals, Inc.

Percutaneous closure of acute aorto-right ventricular fistula following transcatheter bicuspid aortic valve replacement.

PubMed

Nakamura, Kenta; Passeri, Jonathan J; Inglessis-Azuaje, Ignacio

2017-07-01

We report a case of acute aorto-right ventricular fistula following transcatheter bicuspid aortic valve replacement and subsequent percutaneous closure. The diagnosis and treatment of this rare complication is illustrated through multi-modality imaging. We hypothesize that the patient's heavily calcified bicuspid aortic valve anatomy led to asymmetric deployment of the transcatheter aortic valve replacement (TAVR) prosthesis, traumatizing the right sinus of Valsalva at the distal edge of the TAVR stent and ultimately fistulized to the right ventricle. The patient acutely decompensated with heart failure five days after TAVR and underwent emergent intervention. The aorto-right ventricular fistula was closed using an 18-mm septal occluder device with marked clinical recovery. Transcatheter closure is a viable treatment option for acute aorto-right ventricular fistula. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Testing large aspheric surfaces with complementary annular subaperture interferometric method

NASA Astrophysics Data System (ADS)

Hou, Xi; Wu, Fan; Lei, Baiping; Fan, Bin; Chen, Qiang

2008-07-01

Annular subaperture interferometric method has provided an alternative solution to testing rotationally symmetric aspheric surfaces with low cost and flexibility. However, some new challenges, particularly in the motion and algorithm components, appear when applied to large aspheric surfaces with large departure in the practical engineering. Based on our previously reported annular subaperture reconstruction algorithm with Zernike annular polynomials and matrix method, and the experimental results for an approximate 130-mm diameter and f/2 parabolic mirror, an experimental investigation by testing an approximate 302-mm diameter and f/1.7 parabolic mirror with the complementary annular subaperture interferometric method is presented. We have focused on full-aperture reconstruction accuracy, and discuss some error effects and limitations of testing larger aspheric surfaces with the annular subaperture method. Some considerations about testing sector segment with complementary sector subapertures are provided.

Apparatus for removing a contaminant from a fluid stream

DOEpatents

Brewster, M.D.; Posa, R.P.

1998-12-22

A device for removing a contaminant from a fluid stream flowing within a conduit is disclosed. The device includes a container and a barrier. The container has a first wall generated about an axis and a second wall generated about the same axis. The first wall defines a first volume therewithin, while the first and second walls define an annular second volume therebetween. Both the first and second volumes are sealed at one end of the device, while at the other end of the device the second volume only is sealed. A filter material occupies the second volume. The first and second walls are permeable to the fluid stream and are capable of retaining the filter material in the second volume. The barrier is impermeable to the fluid stream and creates a seal between the second wall and the conduit wall. The barrier is positioned adjacent the other end of the device such that when the other end of the device is the upstream end, the fluid stream must sequentially pass into the first volume, through the first wall, into the second volume and through the filter material, and through the second wall. 4 figs.

Apparatus for removing a contaminant from a fluid stream

DOEpatents

Brewster, Michael D.; Posa, Richard P.

1998-01-01

A device for removing a contaminant from a fluid stream flowing within a conduit is disclosed. The device includes a container and a barrier. The container has a first wall generated about an axis and a second wall generated about the same axis. The first wall defines a first volume therewithin, while the first and second walls define an annular second volume therebetween. Both the first and second volumes are sealed at one end of the device, while at the other end of the device the second volume only is sealed. A filter material occupies the second volume. The first and second walls are permeable to the fluid stream and are capable of retaining the filter material in the second volume. The barrier is impermeable to the fluid stream and creates a seal between the second wall and the conduit wall. The barrier is positioned adjacent the other end of the device such that when the other end of the device is the upstream end, the fluid stream must sequentially pass into the first volume, through the first wall, into the second volume and through the filter material, and through the second wall.

Evaluation of a new tension relief system for securing wound closure: A single-centre, Chinese cohort study

PubMed Central

Huahui, Zhang; Dan, Xue; Hongfei, Jiang; Hang, Hu; Chunmao, Han; Haitao, Ren; Jianxin, Yu; Zhiping, Tao

2016-01-01

BACKGROUND Wounds that have been closed under excessive tension, and skin defects that cannot be closed primarily, pose a daily challenge for the reconstructive surgeon. OBJECTIVE To evaluate a new tension relief system (TRS) device for skin stretching and secure wound closure. METHODS From September 2013 to March 2014, a consecutive series of 41 Chinese patients with 43 wounds were enrolled for application of 50 cycles of TRS therapy. TRS was used for two main clinical applications: closure of a variety of surgical/traumatic wounds; and securing wound closure after high-tension suture closure. Basic information and details regarding this therapy and its complications were recorded. Follow-up visits were conducted three to six months after wound closure. RESULTS Mean residual wound width decreased approximately 20% every two days during cycles of TRS therapy. Infection was the most common complication (five cases). Other complications included dehiscence (two cases) and pressure ulcer (one case). At the six-month follow-up visit, (21 wounds in 20 patients), both the extent of healing and the scar were acceptable. DISCUSSION There are no absolute contraindications to TRS therapy. The authors have formulated instructions for the prevention and treatment of the most common complications. CONCLUSIONS The results demonstrate that TRS therapy is a simple, effective method for primary closure of difficult wounds, and large skin and soft-tissue defects. Larger randomized studies are required to further evaluate of the effectiveness, indications, complications and cost effectiveness of this innovative TRS therapy. PMID:28439506

Arthroscopic Treatment of Annular Drive Through and Radial Lateral Collateral Ligament Articular-Side Tear of the Elbow.

PubMed

Arrigoni, Paolo; D'Ambrosi, Riccardo; Randelli, Pietro

2015-12-01

An elongation or partial articular-sided tear of the radial lateral collateral ligament (R-LCL) is a rare injury causing disability and instability of the elbow. In our experience this condition is often associated with a pathologic sign of the annular ligament named the "annular drive through" caused by a redundancy of the ligament. The benefits of performing an arthroscopic procedure for surgical stabilization of the R-LCL include smaller incisions with less soft-tissue dissection, better visualization of the joint, better repair accessibility, and elimination of the annular drive-through sign. The main steps of the operation are as follows: evaluation of annular drive through, inspection of the radial side of the joint, anterior capsulotomy, insertion of a suture anchor through the anterolateral portal, shuttling of the suture anchor through the ligament, and elimination of the annular drive-through sign. By use of this technique, it is possible to repair a lesion of the R-LCL with a suture anchor that ensures an anatomic repair and, at the same time, returns the annular ligament to its physiological tension.

Fundamental Studies and Device Development in Beta Silicon Carbide

DTIC Science & Technology

1990-02-28

8217 and (d) 14.5- off (000 1) tovwird 111201 axis, respectively. 25p atoms are considered to exist in monoatomic form. The overall reaction fort the...IOOOA thick oxide layer was thermally grown in a dry oxygen ambient at 1200°C. The oxide layer was etched and a layer of gold , 񓟰A in thickness, was...and gold etching in a KI:12:H20 solution, 4:1:40 by weight. The diodes were separated from the field region by a 100 pm wide annular ring. The

49 CFR 179.100-13 - Venting, loading and unloading valves, measuring and sampling devices.

Code of Federal Regulations, 2010 CFR

2010-10-01

... permit testing thermometer well for leaks without complete removal of the closure may be used. (d) An... cast, forged or fabricated metal. Each sump or siphon bowl must be of good welding quality in...

Coaxial fuel and air premixer for a gas turbine combustor

DOEpatents

York, William D; Ziminsky, Willy S; Lacy, Benjamin P

2013-05-21

An air/fuel premixer comprising a peripheral wall defining a mixing chamber, a nozzle disposed at least partially within the peripheral wall comprising an outer annular wall spaced from the peripheral wall so as to define an outer air passage between the peripheral wall and the outer annular wall, an inner annular wall disposed at least partially within and spaced from the outer annular wall, so as to define an inner air passage, and at least one fuel gas annulus between the outer annular wall and the inner annular wall, the at least one fuel gas annulus defining at least one fuel gas passage, at least one air inlet for introducing air through the inner air passage and the outer air passage to the mixing chamber, and at least one fuel inlet for injecting fuel through the fuel gas passage to the mixing chamber to form an air/fuel mixture.

Percutaneous endoscopic intra-annular subligamentous herniotomy for large central disc herniation: a technical case report.

PubMed

Lee, Sang-Ho; Choi, Kyung-Chul; Baek, Oon Ki; Kim, Ho Jin; Yoo, Seung-Hwa

2014-04-01

Technical case report. To describe the novel technique of percutaneous endoscopic herniotomy using a unilateral intra-annular subligamentous approach for the treatment of large centrally herniated discs. Open discectomy for large central disc herniations may have poor long-term prognosis due to heavy loss of intervertebral disc tissue, segmental instability, and recurrence of pain. Six consecutive patients who presented with back and leg pain, and/or weakness due to a large central disc herniation were treated using percutaneous endoscopic herniotomy with a unilateral intra-annular subligamentous approach. The patients experienced relief of symptoms and intervertebral disc spaces were well maintained. The annular defects were noted to be in the process of healing and recovery. Percutaneous endoscopic unilateral intra-annular subligamentous herniotomy was an effective and affordable minimally invasive procedure for patients with large central disc herniations, allowing preservation of nonpathological intradiscal tissue through a concentric outer-layer annular approach.

Method of making an aero-derivative gas turbine engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiebe, David J.

A method of making an aero-derivative gas turbine engine (100) is provided. A combustor outer casing (68) is removed from an existing aero gas turbine engine (60). An annular combustor (84) is removed from the existing aero gas turbine engine. A first row of turbine vanes (38) is removed from the existing aero gas turbine engine. A can annular combustor assembly (122) is installed within the existing aero gas turbine engine. The can annular combustor assembly is configured to accelerate and orient combustion gasses directly onto a first row of turbine blades of the existing aero gas turbine engine. Amore » can annular combustor assembly outer casing (108) is installed to produce the aero-derivative gas turbine engine (100). The can annular combustor assembly is installed within an axial span (85) of the existing aero gas turbine engine vacated by the annular combustor and the first row of turbine vanes.« less

Annular core liquid-salt cooled reactor with multiple fuel and blanket zones

DOEpatents

Peterson, Per F.

2013-05-14

A liquid fluoride salt cooled, high temperature reactor having a reactor vessel with a pebble-bed reactor core. The reactor core comprises a pebble injection inlet located at a bottom end of the reactor core and a pebble defueling outlet located at a top end of the reactor core, an inner reflector, outer reflector, and an annular pebble-bed region disposed in between the inner reflector and outer reflector. The annular pebble-bed region comprises an annular channel configured for receiving pebble fuel at the pebble injection inlet, the pebble fuel comprising a combination of seed and blanket pebbles having a density lower than the coolant such that the pebbles have positive buoyancy and migrate upward in said annular pebble-bed region toward the defueling outlet. The annular pebble-bed region comprises alternating radial layers of seed pebbles and blanket pebbles.

RADIATION SOURCE

DOEpatents

Gow, J.D.

1961-06-27

An improved version of a crossed electric and magnetic field plasma producing and containing device of the general character disclosed in U. S. Patent No. 2,967,943 is described. This device employs an annular magnet encased within an anode and a pair of cathodes respectively coaxially spaced from the opposite ends of the anode to establish crossed field electron trapping regions adjacent the ends of the anode. The trapping regions are communicably connected through the throat of the anode and the electric field negatively increases in opposite axial directions from the center of the throat. Electrons are trapped within the two trapping regions and throat to serve as a source of intense ionization to gas introduced thereto, the ions in copious quantities being attracted to the cathodes to bombard neutron productive targets dlsposed - thereat.

THERMO-ELECTRIC GENERATOR

DOEpatents

Jordan, K.C.

1958-07-22

The conversion of heat energy into electrical energy by a small compact device is descrtbed. Where the heat energy is supplied by a radioactive material and thermopIIes convert the heat to electrical energy. The particular battery construction includes two insulating discs with conductive rods disposed between them to form a circular cage. In the center of the cage is disposed a cup in which the sealed radioactive source is located. Each thermopile is formed by connecting wires from two adjacent rods to a potnt on an annular ring fastened to the outside of the cup, the ring having insulation on its surface to prevent electrica1 contact with the thermopiles. One advantage of this battery construction is that the radioactive source may be inserted after the device is fabricated, reducing the radiation hazard to personnel assembling the battery.

Pressure ulcer: an unreported complication of the Safeguard® hemostasis device. No need to crack under pressure

PubMed Central

Moretti, Claudio; Quadri, Giorgio; Gaita, Fiorenzo; Sheiban, Imad

2011-01-01

Diagnostic cardiac catheterizations are predominantly performed using the femoral artery access. Several devices have been developed to aid in the closure of femoral arteriotomy. Safeguard® is a new pneumatic compression device that has been developed for compression of the femoral artery after brief manual compression. We hereby report the case of an elderly patient who underwent a percutaneous coronary intervention via the femoral artery in whom a Safeguard™ device, left overnight because of persistent oozing, provoked an extensive pressure ulcer. Knowledge of this potential complication is important to minimize its occurance and provide appropriate treatment. PMID:21977303

Pressure ulcer: an unreported complication of the Safeguard® hemostasis device. No need to crack under pressure.

PubMed

Moretti, Claudio; Quadri, Giorgio; Gaita, Fiorenzo; Sheiban, Imad

2011-01-01

Diagnostic cardiac catheterizations are predominantly performed using the femoral artery access. Several devices have been developed to aid in the closure of femoral arteriotomy.Safeguard® is a new pneumatic compression device that has been developed for compression of the femoral artery after brief manual compression. We hereby report the case of an elderly patient who underwent a percutaneous coronary intervention via the femoral artery in whom a Safeguard™ device, left overnight because of persistent oozing, provoked an extensive pressure ulcer. Knowledge of this potential complication is important to minimize its occurance and provide appropriate treatment.

Do we need a femoral artery route for transvenous PDA closure in children with ADO-I?

PubMed

Baykan, Ali; Narin, Nazmi; Özyurt, Abdullah; Argun, Mustafa; Pamukçu, Özge; Onan, Sertaç H; Sezer, Sadettin; Baykan, Zeynep; Üzüm, Kazım

2015-03-01

The standard procedure in percutaneous closure of patent ductus arteriosus (PDA) with Amplatzer duct occluder-I (ADO-I) is transvenous closure guided by aortic access through femoral artery. The current study aims to compare the procedures for PDA closure with ADO-I: only transvenous access with the standard procedure. This study was designed retrospectively and 101 pediatric patients were included. PDA closure was done by only femoral venous access in 19 of them (group 1), arterial and venous access used in 92 patients (group 2) between 2004 to 2012 years. The position of the device and residual shunt in group1 was evaluated by the guidance of the aortogram obtained during the return phase of the pulmonary artery injection and guidance of transthoracic echocardiography. Shapiro-Wilk's test, Mann-Whitney U, chi-squared tests were used for statistical comparison. The procedure was successful in 18 (95%) patients in group 1 and 90 (98%) patients in group 2. Complications including the pulmonary artery embolization (n=1), protrusion to pulmonary artery (n=1), inguinal hematoma (n=3), bleeding (n=2) were only detected in group 2. In other words, while complications were observed in 7 (7.2%) patients in group 2, no minor/major complication was observed in group 1. Complete closure in group 1 was: in catheterization room 14 (77.8%), at 24th hour in 2 (11.1%), at first month in 2 (11.1%). Complete closure in group 2 was: 66 (73.4%) patients in the catheterization room, 21 (23.3%) at 24th hour, 3 (3.3%) at first month, complete closure occurred at the end of first month. In percutaneouse PDA closure via ADO-I, this technique can be a choice for patients whose femoral artery could not be accessed, or access is impossible/contraindicated. But for the reliability and validity of this method, randomized multicenter clinical studies are necessary.

Do we need a femoral artery route for transvenous PDA closure in children with ADO-I?

PubMed Central

Baykan, Ali; Narin, Nazmi; Özyurt, Abdullah; Argun, Mustafa; Pamukçu, Özge; Onan, Sertaç H.; Sezer, Sadettin; Baykan, Zeynep; Üzüm, Kazım

2015-01-01

Objective: The standard procedure in percutaneous closure of patent ductus arteriosus (PDA) with Amplatzer duct occluder-I (ADO-I) is transvenous closure guided by aortic access through femoral artery. The current study aims to compare the procedures for PDA closure with ADO-I: only transvenous access with the standard procedure. Methods: This study was designed retrospectively and 101 pediatric patients were included. PDA closure was done by only femoral venous access in 19 of them (group 1), arterial and venous access used in 92 patients (group 2) between 2004 to 2012 years. The position of the device and residual shunt in group1 was evaluated by the guidance of the aortogram obtained during the return phase of the pulmonary artery injection and guidance of transthoracic echocardiography. Shapiro-Wilk’s test, Mann-Whitney U, chi-squared tests were used for statistical comparison. Results: The procedure was successful in 18 (95%) patients in group 1 and 90 (98%) patients in group 2. Complications including the pulmonary artery embolization (n=1), protrusion to pulmonary artery (n=1), inguinal hematoma (n=3), bleeding (n=2) were only detected in group 2. In other words, while complications were observed in 7 (7.2%) patients in group 2, no minor/major complication was observed in group 1. Complete closure in group 1 was: in catheterization room 14 (77.8%), at 24th hour in 2 (11.1%), at first month in 2 (11.1%). Complete closure in group 2 was: 66 (73.4%) patients in the catheterization room, 21 (23.3%) at 24th hour, 3 (3.3%) at first month, complete closure occurred at the end of first month. Conclusion: In percutaneouse PDA closure via ADO-I, this technique can be a choice for patients whose femoral artery could not be accessed, or access is impossible/contraindicated. But for the reliability and validity of this method, randomized multicenter clinical studies are necessary. PMID:25333978

Intracardiac Echocardiography for Structural Heart and Electrophysiological Interventions.

PubMed

Basman, Craig; Parmar, Yuvrajsinh J; Kronzon, Itzhak

2017-09-06

With an increasing number of interventional procedures performed for structural heart disease and cardiac arrhythmias each year, echocardiographic guidance is necessary for safe and efficient results. The purpose of this review article is to overview the principles of intracardiac echocardiography (ICE) and describes the peri-interventional role of ICE in a variety of structural heart disease and electrophysiological interventions. Both transthoracic (TTE) and transesophageal echocardiography have limitations. ICE provides the advantage of imaging from within the heart, providing shorter image distances and higher resolution. ICE may be performed without sedation and avoids esophageal intubation as with transesophageal echocardiography (TEE). Limitations of ICE include the need for additional venous access with possibility of vascular complications, potentially higher costs, and a learning curve for new operators. Data supports the use of ICE in guiding device closure of interatrial shunts, transseptal puncture, and electrophysiologic procedures. This paper reviews the more recent reports that ICE may be used for primary guidance or as a supplement to TEE in patients undergoing left atrial appendage (LAA) closure, interatrial shunt closure, transaortic valve implantation (TAVI), percutaneous mitral valve repair (PMVR), paravalvular leak (PVL) closure, aortic interventions, transcatheter pulmonary valve replacement (tPVR), ventricular septal defect (VSD), and patent ductus arteriosus (PDA) closure. ICE imaging technology will continue to expand and help improve structural heart and electrophysiology interventions.

Laser tissue melding: use of 1.32-μm computerized Nd:YAG laser, results of leak/burst strength studies in microsurgical procedures

NASA Astrophysics Data System (ADS)

Anderson, Dallas W.; Hsu, Tung M.; Halpern, Steven J.; Honaker, Arnold

1993-07-01

The ProClosureTM System (PCS) consists of a low power 1.32micrometers Nd:YAG laser coupled to a handheld disposable fiber optic device. The system has been designed to perform a wide range of tissue welding applications such as cosmetic skin closure,vascular surgery, and minimally invasive surgical procedures normally performed with sutures and staples. Utilizing a wavelength for tissue fusion that is least distracted by medium in the surgical field coupled with a computerized delivery system allows for a more precise application (+/- 5%) of laser energy to the tissue. The study design involved the micro-surgical anastomosis of twenty Sprague-Dawley rats (vas deferens) and twenty-one Sprague-Dawley rats (femoral arteries). Each rat is its own contralateral control. Laser repair time is approximately one-third that of conventional suturing. Postoperative dissection and burst strength testing was conducted at day 0, 1, 7, and 14. At each postoperative interval, the mean leak/burst strength for laser-assisted closure v. control, was markedly higher. The precise application of energy fluence resulting from ProClosure's computerized system yields an initial strength and a fluid static seal that is superior to conventional suture closure.

Simple skin-stretching device in assisted tension-free wound closure

PubMed Central

Cheng, Li-Fu; Lee, Jiunn-Tat; Hsu, Honda; Wu, Meng-Si

2017-01-01

Background Numerous conventional wound reconstruction methods such as wound undermining with direct suture, skin graft, and flap surgery can be used to treat large wounds. The adequate undermining of the skin flaps of a wound is a commonly used technique for achieving the closure of large tension wounds; however, the use of tension to approximate and suture the skin flaps can cause ischemic marginal necrosis. The purpose of this study is to use elastic rubber bands to relieve the tension of direct wound closure for simultaneously minimizing the risks of wound dehiscence and wound edge ischemia that lead to necrosis. Materials and Methods This retrospective study was conducted to evaluate our clinical experiences with 22 large wounds, which involved performing primary closures under a considerable amount of tension by using elastic rubber bands in a skin-stretching technique following a wide undermining procedure. Assessment of the results entailed complete wound healing and related complications. Results All 22 wounds in our study showed fair to good results except for one. The mean success rate was approximately 95.45%. Conclusion The simple skin-stretching design enabled tension-free skin closure, which pulled the bilateral undermining skin flaps as bilateral fasciocutaneous advancement flaps. The skin-stretching technique was generally successful. PMID:28195891

Fenestrated atrial septal defect percutaneously occluded by a single device: procedural and financial considerations.

PubMed

Tal, Roie; Dahud, Qarawani; Lorber, Avraham

2013-06-01

A 45-year-old patient presented with a cerebrovascular attack and was subsequently found to have a multi-fenestrated atrial septal defect. Various therapeutic options for percutaneous transcatheter closure with their respective benefits and flaws are discussed, as well as procedural and financial considerations. The decision making process leading to a successful result using a single occlusive device is presented, alongside a review of the literature.

An X-band high-impedance relativistic klystron amplifier with an annular explosive cathode

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Danni; Zhang, Jun, E-mail: zhangjun@nudt.edu.cn; Zhong, Huihuang

2015-11-15

The feasibility of employing an annular beam instead of a solid one in the X-band high-impedance relativistic klystron amplifier (RKA) is investigated in theory and simulation. Small-signal theory analysis indicates that the optimum bunching distance, fundamental current modulation depth, beam-coupling coefficient, and beam-loaded quality factor of annular beams are all larger than the corresponding parameters of solid beams at the same beam voltage and current. An annular beam RKA and a solid beam RKA with almost the same geometric parameters are compared in particle-in-cell simulation. Output microwave power of 100 MW, gain of 50 dB, and power conversion efficiency of 42% aremore » obtained in an annular beam RKA. The annular beam needs a 15% lower uniform guiding magnetic field than the solid beam. Our investigations demonstrate that we are able to use a simple annular explosive cathode immersed in a lower uniform magnetic field instead of a solid thermionic cathode in a complicated partially shielding magnetic field for designing high-impedance RKA, which avoids high temperature requirement, complicated electron-optical system, large area convergence, high current density, and emission uniformity for the solid beam. An equivalent method for the annular beam and the solid beam on bunching features is proposed and agrees with the simulation. The annular beam has the primary advantages over the solid beam that it can employ the immersing uniform magnetic field avoiding the complicated shielding magnetic field system and needs a lower optimum guiding field due to the smaller space charge effect.« less

Tricuspid Annular Geometry: A Three-Dimensional Transesophageal Echocardiographic Study

PubMed Central

Mahmood, Feroze; Kim, Han; Chaudary, Bilal; Bergman, Remco; Matyal, Robina; Gerstle, Jeniffer; Gorman, Joseph H.; Gorman, Robert C.; Khabbaz, Kamal R.

2013-01-01

Objective To demonstrate the clinical feasibility of accurately measuring tricuspid annular area by 3-dimensional (3D) transesophageal echocardiography (TEE) and to assess the geometric differences based on the presence of tricuspid regurgitation (TR). Also, the shape of the tricuspid annulus was compared with previous descriptions in the literature. Design Prospective. Setting Tertiary care university hospital. Interventions Three-dimensional TEE. Participants Patients undergoing cardiac surgery. Measurements and Main Results Volumetric data sets from 20 patients were acquired by 3D TEE and prospectively analyzed. Comparisons in annular geometry were made between groups based on the presence of TR. The QLab (Philips Medical Systems, Andover, MA) software package was used to calculate tricuspid annular area by both linear elliptical dimensions and planimetry. Further analyses were performed in the 4D Cardio-View (TomTec Corporation GmBH, Munich, Germany) and MATLAB (Natick, MA) software environments to accurately assess annular shape. It was found that patients with greater TR had an eccentrically dilated annulus with a larger annular area. Also, the area as measured by the linear ellipse method was overestimated as compared to the planimetry method. Furthermore, the irregular saddle-shaped geometry of the tricuspid annulus was confirmed through the mathematic model developed by the authors. Conclusions Three-dimensional TEE can be used to measure the tricuspid annular area in a clinically feasible fashion, with an eccentric dilation seen in patients with TR. The tricuspid annulus shape is complex, with annular high and low points, and annular area calculation based on linear measurements significantly overestimates 3D planimetered area. PMID:23725682

Extended residence time centrifugal contactor design modification and centrifugal contactor vane plate valving apparatus for extending mixing zone residence time

DOEpatents

Wardle, Kent E.

2017-06-06

The present invention provides an annular centrifugal contactor, having a housing adapted to receive a plurality of flowing liquids; a rotor on the interior of the housing; an annular mixing zone, wherein the annular mixing zone has a plurality of fluid retention reservoirs with ingress apertures near the bottom of the annular mixing zone and egress apertures located above the ingress apertures of the annular mixing zone; and an adjustable vane plate stem, wherein the stem can be raised to restrict the flow of a liquid into the rotor or lowered to increase the flow of the liquid into the rotor.

Annular Solar Eclipse of 10 May 1994

NASA Technical Reports Server (NTRS)

Espenak, Fred; Anderson, Jay

1993-01-01

An annular eclipse of the Sun will be widely visible from the Western Hemisphere on 10 May 1994. The path of the Moon's shadow passes through Mexico, the United States of America, maritime Canada, the North Atlantic, the Azores and Morocco. Detailed predictions for this event are presented and include tables of geographic coordinates of the annular path, local circumstances for hundreds of cities, maps of the path of annular and partial eclipse, weather prospects, and the lunar limb profile.

Laser-induced retinal damage thresholds for annular retinal beam profiles

NASA Astrophysics Data System (ADS)

Kennedy, Paul K.; Zuclich, Joseph A.; Lund, David J.; Edsall, Peter R.; Till, Stephen; Stuck, Bruce E.; Hollins, Richard C.

2004-07-01

The dependence of retinal damage thresholds on laser spot size, for annular retinal beam profiles, was measured in vivo for 3 μs, 590 nm pulses from a flashlamp-pumped dye laser. Minimum Visible Lesion (MVL)ED50 thresholds in rhesus were measured for annular retinal beam profiles covering 5, 10, and 20 mrad of visual field; which correspond to outer beam diameters of roughly 70, 160, and 300 μm, respectively, on the primate retina. Annular beam profiles at the retinal plane were achieved using a telescopic imaging system, with the focal properties of the eye represented as an equivalent thin lens, and all annular beam profiles had a 37% central obscuration. As a check on experimental data, theoretical MVL-ED50 thresholds for annular beam exposures were calculated using the Thompson-Gerstman granular model of laser-induced thermal damage to the retina. Threshold calculations were performed for the three experimental beam diameters and for an intermediate case with an outer beam diameter of 230 μm. Results indicate that the threshold vs. spot size trends, for annular beams, are similar to the trends for top hat beams determined in a previous study; i.e., the threshold dose varies with the retinal image area for larger image sizes. The model correctly predicts the threshold vs. spot size trends seen in the biological data, for both annular and top hat retinal beam profiles.

Hybrid approach for closure of muscular ventricular septal defects

PubMed Central

Haponiuk, Ireneusz; Chojnicki, Maciej; Jaworski, Radoslaw; Steffek, Mariusz; Juscinski, Jacek; Sroka, Mariusz; Fiszer, Roland; Sendrowska, Aneta; Gierat-Haponiuk, Katarzyna; Maruszewski, Bohdan

2013-01-01

Background The complexity of ventricular septal defects in early infancy led to development of new mini-invasive techniques based on collaboration of cardiac surgeons with interventional cardiologists, called hybrid procedures. Hybrid therapies aim to combine the advantages of surgical and interventional techniques in an effort to reduce the invasiveness. The aim of this study was to present our approach with mVSD patients and initial results in the development of a mini-invasive hybrid procedure in the Gdansk Hybrid Heartlink Programme (GHHP) at the Department of Pediatric Cardiac Surgery, Pomeranian Centre of Traumatology in Gdansk, Poland. Material/Methods The group of 11 children with mVSDs was enrolled in GHHP and 6 were finally qualified to hybrid trans-ventricular mVSD device closure. Mean age at time of hybrid procedure was 8.22 months (range: from 2.7 to 17.8 months, SD=5.1) and mean body weight was 6.3 kg (range: from 3.4 to 7.5 kg, SD=1.5). Results The implants of choice were Amplatzer VSD Occluder and Amplatzer Duct Occluder II (AGA Med. Corp, USA). The position of the implants was checked carefully before releasing the device with both transesophageal echocardiography and epicardial echocardiography. All patients survived and their general condition improved. No complications occurred. The closure of mVSD was complete in all children. Conclusions Hybrid procedures of periventricular muscular VSD closure appear feasible and effective for patients with septal defects with morphology unsuitable for classic surgical or interventional procedures. The modern strategy of joint cardiac surgical and interventional techniques provides the benefits of close cooperation between cardiac surgeon and interventional cardiologist for selected patients in difficult clinical settings. PMID:23892911

Closure of large patent ductus arteriosus using the Amplatzer Septal Occluder.

PubMed

García-Montes, José A; Camacho-Castro, Anahí; Sandoval-Jones, Juan P; Buendía-Hernández, Alfonso; Calderón-Colmenero, Juan; Patiño-Bahena, Emilia; Zabal, Carlos

2015-03-01

Percutaneous closure of patent ductus arteriosus has become the treatment of choice in many centres. In patients with large ducts and pulmonary hypertension, transcatheter closure has been achieved with success using the Amplatzer Duct Occluder or even the Amplatzer Muscular Ventricular Septal Defect Occluder. We present a series of 17 patients with large and hypertensive ductus arteriosus who were treated with an Amplatzer Septal Occluder. The group had 11 female patients (64.7%) and a mean age of 18.6±12.1 years. The haemodynamic and anatomical data are as follows: pulmonary artery systolic pressure 71.3±31.8 mmHg, pulmonary to systemic flow ratio 3.14±1.36, ductal diameter at the pulmonary end 12.5±3.8 mm, and at the aortic end 20.2±7.7 mm; 14 cases (82.3%) had type A ducts. In 11 patients, we began the procedure using a different device - six with duct occluder and five with ventricular septal occluder - and it was changed because of device embolisation in six (35.3%). All septal occluders were delivered successfully. Residual shunt was moderate in six patients (35.3%), mild in eight (47%), trivial in two (11.8%), and no shunt in one (5.9%). Pulmonary systolic pressure decreased to 48.9±10.8 mmHg after occlusion (p=0.0015). Follow-up in 15 patients (88.2%) for 28.4±14.4 months showed complete closure in all cases but one, and continuous decrease of the pulmonary systolic pressure to 31.4±10.5 mmHg. No complications at follow-up have been reported. The Amplatzer Septal Occluder is a good alternative to percutaneously treat large and hypertensive ductus arteriosus.

[Right atrial appendage thrombosis during atrial fibrillation: an element to look for].

PubMed

Barbati, Giovanni; De Domenico, Renato; Rossi, Stefania; Vecchiato, Elena; Zeppellini, Roberto

2017-03-01

Oral anticoagulant therapy (OAT) is a mainstay of atrial fibrillation (AF) pharmacological treatment. Left atrial appendage closure is a possible treatment, when feasible, in patients with intracerebral hemorrhage during OAT. We report a case of right atrial appendage thrombosis in a patient with chronic AF admitted for syncope due to diuretic-induced orthostatic hypotension. Two years previously, he had undergone left atrial appendage closure with the Amplatzer Cardiac Plug device because of intracerebral hemorrhage during OAT. After neurological consult, OAT was resumed with apixaban 5 mg twice daily, and transesophageal echocardiography performed two months later showed complete resolution of the right atrial appendage thrombosis. This particular case underlines the importance of searching for a possible right atrial appendage thrombosis in patients affected by AF, and suggests that left atrial appendage closure in AF patients not suitable for OAT does not fully eliminate the risk of thromboembolism.

[Synthesis of large wounds of the body wall with rubber elastic band].

PubMed

Petroianu, Andy

2011-01-01

The large wounds of the body wall, due to traumas, removal of tumors or prolonged laparostomies are a difficult surgical challenge with complex treatment. This paper presents the efficacy of the closure of large surgical wounds using rubber elastic bands. One or two circular rubber elastic bands were sutured under mean tension at the opposite edges of 22 large wounds located in different body sites. These rubber strips were replaced when they were broken or re-fixed when they have lost their tension until the complete closure of the wounds. Complete closure was achieved without any other surgical procedure or device in 21 wounds and one wound reduced its dimensions. No major complication due to this treatment was verified. The synthesis of large wounds with rubber elastic bands kept under mean tension is a simple, efficacious and inexpensive surgical option that may be useful for treatment in several circumstances.

49 CFR 173.227 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone B.

Code of Federal Regulations, 2013 CFR

2013-10-01

... are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in place by any means capable of...

49 CFR 173.227 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone B.

Code of Federal Regulations, 2010 CFR

2010-10-01

... are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in place by any means capable of...

49 CFR 173.227 - Materials poisonous by inhalation, Division 6.1, Packing Group I, Hazard Zone B.

Code of Federal Regulations, 2014 CFR

2014-10-01

... are— (i) Closed and tightened to a torque prescribed by the closure manufacturer, using a properly calibrated device that is capable of measuring torque; (ii) Physically held in place by any means capable of...