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1.
J Heart Valve Dis ; 24(4): 420-5, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26897809

RESUMEN

BACKGROUND AND AIM OF THE STUDY: Direct aortic access for transcatheter aortic valve replacement (DA-TAVR) is an important alternative approach in patients with hostile ileo-femoral vessels. Planning the transaortic puncture site and an 'ideal' trajectory towards the annulus plane is important for safe and successful valve implantation. The feasibility of three-dimensional (3D) planning and real-time fluoroscopic image guidance for DA-TAVR was evaluated using pre-procedural multi-detector computed tomography (MDCT) and intra-procedural Dyna CT co-registration approaches. METHODS: Between May 2012 and August 2014, a total of 44 patients (40 mini-sternotomies, four mini-thoracotomies) was selected for DA-TAVR using the authors' MDCT-Dyna CT co-registration approach (32 CoreValve, 12 SAPIEN). Pre-procedural contrast-enhanced multi-slice CT (MSCT) and intra- procedural non-contrast Dyna CT images were co-registered based on cardiac outline and aortic root calcifications. Using a prototype software, the aortic root was segmented and relevant landmarks identified automatically. The intersection of a virtual perpendicular trajectory from the annulus with the greater curvature of the aorta was marked as the planned DA puncture site. The planned DA puncture site, trajectory and relevant landmarks were overlaid onto real-time fluoroscopic images for image guidance during DA-TAVR. RESULTS: Real-time fluoroscopic overlay of planned trajectory was feasible in all 44 cases of DA-TAVR. The mean 2D projection distance error between the actual and planned aortic puncture sites was 1.60 +/- 1.1 cm. The mean angular difference error (measure of co-axiality) between actual and planned DA trajectory was 11.86 +/- 9.3. Errors in distance and co-axiality were lower with the mini-thoracotomy than with the mini-sternotomy approach. The Multi-Slice CT (MSCT)-Dyna CT co-registration technique resulted in significantly less contrast usage, and trended towards shorter fluoroscopy and operative times. There was also a trend towards a reduction in acute kidney injury, but no difference was identified in the degree of paravalvular regurgitation or mortality. CONCLUSION: 3D access planning and real-time image guidance for DA-TAVR is feasible using an MDCT/non-contrast Dyna CT image co-registration-based approach. Such image co-registration strategies improve the accuracy of case planning and safety of valve deployment with a direct aortic approach. Further studies are necessary to determine if these enhancements translate into an improvement in clinical outcomes.


Asunto(s)
Válvula Aórtica/diagnóstico por imagen , Cateterismo Cardíaco/métodos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Imagenología Tridimensional , Tomografía Computarizada Multidetector/métodos , Interpretación de Imagen Radiográfica Asistida por Computador , Radiografía Intervencional/métodos , Anciano , Anciano de 80 o más Años , Cateterismo Cardíaco/instrumentación , Estudios de Factibilidad , Femenino , Fluoroscopía , Prótesis Valvulares Cardíacas , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Diseño de Prótesis , Punciones , Esternotomía , Toracotomía , Resultado del Tratamiento
2.
J Card Surg ; 30(12): 885-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26440901

RESUMEN

We report a 77-year-old male patient with a history of aortic valve bypass with an apicoaortic conduit 11 years ago for severe aortic stenosis, presenting with acute decompensated congestive heart failure. Severe conduit valve regurgitation and was successfully treated with transcatheter aortic valve replacement (TAVR) of the native aortic valve using a self-expanding bioprosthesis followed by transcatheter closure of the apicoaortic conduit.


Asunto(s)
Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Enfermedad Aguda , Anciano , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/cirugía , Bioprótesis , Procedimientos Quirúrgicos Cardíacos/métodos , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Índice de Severidad de la Enfermedad , Factores de Tiempo , Insuficiencia del Tratamiento , Resultado del Tratamiento
3.
J Card Surg ; 30(9): 697-700, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26228701

RESUMEN

Transcatheter mitral valve-in-valve implantation (TMVIV) is an option for patients with mitral prosthetic valve dysfunction who are at high risk for surgical valve replacement. Efficacy and safety of TMVIV is at its infancy. We report a high-risk symptomatic dialysis-dependent end-stage renal disease patient with severe bioprosthetic mitral valve stenosis who had TMVIV performed successfully.


Asunto(s)
Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas/métodos , Fallo Renal Crónico/complicaciones , Estenosis de la Válvula Mitral/cirugía , Válvula Mitral/cirugía , Diálisis , Humanos , Masculino , Persona de Mediana Edad , Estenosis de la Válvula Mitral/etiología , Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
4.
ACS Omega ; 9(10): 11129-11147, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38496999

RESUMEN

The escalating demand for sustainable industrial practices has driven the exploration of innovative materials, prominently exemplified by biodegradable electrospun membranes (BEMs). This review elucidates the pivotal role of these membranes across diverse industrial applications, addressing the imperative for sustainability. Furthermore, a comprehensive overview of biodegradable materials underscores their significance in electrospinning and their role in minimizing the environmental impact through biodegradability. The application of BEMs in various industrial sectors, including water treatment, food packaging, and biomedical applications, are extensively discussed. The environmental impact and sustainability analysis traverse the lifecycle of BEMs, evaluating their production to disposal and emphasizing reduced waste and resource conservation. This review demonstrates the research about BEMs toward an eco-conscious industrial landscape for a sustainable future.

5.
Sci Rep ; 13(1): 19038, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37923742

RESUMEN

Confinement time of electron plasmas trapped using a purely toroidal magnetic field has been found to exceed [Formula: see text] in a small aspect ratio ([Formula: see text], [Formula: see text] and a are device major and minor radius, respectively), partial torus. It improves upon the previously reported confinement time by nearly two orders of magnitude. Lifetime is estimated from the frequency scaling of the linear diocotron mode launched from sections of the wall, that are also used for mode diagnostics. Confinement improves as neutral pressures are reduced to [Formula: see text] in the presence of a steady state magnetic field of 200 Gauss ([Formula: see text] with droop [Formula: see text]) at [Formula: see text] electron injection energies. With reduced pressures the role of (ion driven) instability diminishes and loss mechanisms resulting from elastic electron-neutral (e-n) and the ubiquitous electron-electron (e-e) scattering seem to play an important role which suggests low electron temperatures. The contribution to electron population resulting from the ionization of background neutral gas at these temperatures and pressures are expected to be insignificant and is corroborated in our experiments.

6.
Eur J Echocardiogr ; 12(11): 857-64, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21890470

RESUMEN

AIMS: There is controversy surrounding the accuracy of echo-Doppler variables, including early mitral inflow/mitral annular velocity (E/e'), for estimating left ventricular filling pressure (LVFP) in patients with depressed ejection fraction (EF < 50%). METHODS AND RESULTS: The American Society of Echocardiography-European Association of Echocardiography (ASE-EAE) algorithm for diastolic function in depressed LVEF was retrospectively applied to a database of patients who underwent echocardiography ≤20 min of cardiac catheterization. LV pre-atrial contraction pressure (pre-A) ≥15 mmHg was elevated. Of 62 patients studied, the mean age was 53.6 ± 10.6 years and the mean LVEF was 27.2 ± 11.8%. The correlations of E/e' (R = 0.43, P = 0.0005) and E (R = 0.39, P = 0.002) with LV pre-A were modest, compared with pulmonary artery pressure (PAP, R = 0.69, P = 0.0006), E/late mitral (A) velocity (R = 0.52, P < 0.0001), and mitral deceleration time (DT, R = -0.51, P < 0.0001). Using the ASE-ESE algorithm starting with E/A, E, and DT, 54 of 62 patients were accurately classified to predict LV pre-A >15 or <15 mmHg (sensitivity = 84%, specificity = 80%, area under the curve = 0.86, P < 0.001). The 6 of 6 patients with E/A < 1 and E < 50 and the 14 of 15 (93%) patients with E/A> 2 and DT < 150 were correctly classified as having normal and elevated LVFP, respectively, while 34 of 41 (83%) patients with E/A = 1-2 or E/A<1 and E>50 cm/s were correctly classified using the addition of E/e' and PAP. CONCLUSION: This retrospective study shows that in this population with depressed LVEF, no single echo-Doppler variable had high accuracy for predicting LV pre-A ≥15 mmHg. However, the ASE-EAE algorithm using multiple variables predicted LVFP with good accuracy, superior to any single echo-Doppler variable alone.


Asunto(s)
Cateterismo Cardíaco/normas , Ecocardiografía Doppler/normas , Insuficiencia Cardíaca/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Disfunción Ventricular Izquierda/diagnóstico por imagen , Europa (Continente) , Femenino , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Sociedades Médicas , Estados Unidos , Disfunción Ventricular Izquierda/fisiopatología
7.
3 Biotech ; 11(7): 315, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34123694

RESUMEN

This study aimed to assess the antidiabetic, and antioxidant potential of Rhynchostylis retusa and Euphorbia neriifolia, well known for traditional ethnomedicinal uses in North-east India. Leaf extracts prepared in water, methanol and petroleum ether were evaluated for in vitro antidiabetic and antioxidant assay using α-amylase inhibition, glucose diffusion method and DPPH radical scavenging activity. The α-amylase inhibition with E. neriifolia methanolic extract at 400 µg/ml (66.67%) and R. retusa aqueous extract at 300 µg/ml (58.15%) were stronger than in equivalent concentrations of acarbose, i.e., 62.17, and 51.52%, respectively. Aqueous extract R. retusa showed a maximum 67.65% inhibition of glucose diffusion at 180 min in comparison to control without leaf extract. The DPPH radical scavenging activity of E. neriifolia extract in methanol was significantly better than equivalent aqueous or ether extract. However, the solvent choice had little impact on antioxidant activity in R. retusa. GC-MS analysis revealed the presence of a large number of phytochemicals in methanol fraction of E. neriifolia aqueous extracts in comparison to R. retusa. Though the in vitro α-amylase inhibition or glucose diffusion retardation implied potential medicinal use of endangered orchid R. retusa and E. neriifolia, further investigation may be warranted for identification of relevant bio-active compounds and in vivo validation of their pharmacological properties.

8.
Cardiovasc Revasc Med ; 21(11S): 100-102, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31279538

RESUMEN

Ventricular perforation is a rare complication during a high-risk percutaneous coronary intervention (PCI) when supported by Impella® (Abiomed). However, instrumentation of the left ventricle several days after transmural infarct potentially increases susceptibility for perforation. While a patient is on Impella support, physicians should review ventriculograms carefully to detect perforation and should consider the presence of a decompressed ventricle, the absence of normal systolic pressure and the movement of contrast from the ventricle into the aorta bypassing the left ventricular ejection. Immediate removal of the Impella if a perforation occurs must be avoided. Retrieving the device would risk a catastrophic bleed, while alternative repair techniques are available. Here, we describe a patient with a left ventricle perforation that occurred during a high-risk PCI supported by an Impella device. ANNOTATED SUMMARY: The repair of a left ventricle perforation during high-risk PCI in a patient who had an unrecognized left ventricular perforation is described. Physicians are encouraged to carefully review ventriculograms to identify the subtle changes that can indicate a perforation. Further, immediate removal of the temporary LVAD should be avoided to minimize the risk of catastrophic bleeds.


Asunto(s)
Ventrículos Cardíacos , Intervención Coronaria Percutánea , Lesiones Cardíacas , Corazón Auxiliar , Hemorragia , Humanos
9.
Am J Cardiol ; 108(8): 1096-101, 2011 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21791329

RESUMEN

Current guidelines state that patients with compatible symptoms and ST-segment elevation (STE) in ≥2 contiguous electrocardiographic leads should undergo immediate reperfusion therapy. Aggressive attempts at decreasing door-to-balloon times have led to more frequent activation of primary percutaneous coronary intervention (pPCI) protocols. However, it remains crucial to correctly differentiate STE myocardial infarction (STEMI) from nonischemic STE (NISTE). We assessed the ability of experienced interventional cardiologists in determining whether STE represents acute STEMI or NISTE. Seven readers studied electrocardiograms of consecutive patients showing STE. Patients with left bundle branch block or ventricular rhythms were excluded. Readers decided if, based on electrocardiographic results, they would have activated the pPCI protocol. If NISTE was chosen, readers selected from 12 possible explanations as to why STE was present. Of 84 patients, 40 (48%) had adjudicated STEMI. The percentage for which readers recommended pPCI varied (33% to 75%). Readers' sensitivity and specificity ranged from 55% to 83% (average 71%) and 32% to 86% (average 63%), respectively. Positive and negative predictive values ranged from 52% to 79% (average 66%) and 67% to 79% (average 71%), respectively. Broad inconsistencies existed among readers as to the chosen reasons for NISTE classification. In conclusion, we found wide variations in experienced interventional cardiologists in differentiating STEMI with a need for pPCI from NISTE.


Asunto(s)
Dolor en el Pecho/diagnóstico , Enfermedad de la Arteria Coronaria/diagnóstico , Vasoespasmo Coronario/diagnóstico , Electrocardiografía , Infarto del Miocardio/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia Coronaria con Balón , Dolor en el Pecho/etiología , Dolor en el Pecho/terapia , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/terapia , Vasoespasmo Coronario/complicaciones , Diagnóstico Diferencial , Errores Diagnósticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Infarto del Miocardio/terapia , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad
11.
J Am Soc Echocardiogr ; 23(12): 1273-80, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20970305

RESUMEN

BACKGROUND: There are few data on the impact of left ventricular (LV) filling pressure on systolic and diastolic myocardial mechanics in patients with cardiac disease and preserved LV ejection fraction (LVEF) (≥ 50%). METHODS: Patients referred for cardiac catheterization underwent comprehensive echocardiography within 20 minutes of catheterization. Strain and strain rate in longitudinal, radial, and circumferential directions and torsion were measured in systole and diastole. LV preatrial contraction pressure (pre-A) was measured and averaged over 10 cardiac cycles. RESULTS: Sixty patients were studied (mean age, 55.3 ± 8.9 years). The 30 patients with LV pre-A ≥ 15 mm Hg had significantly lower longitudinal systolic strain and radial, circumferential, and torsional systolic strain rates than the 30 patients with LV pre-A < 15 mm Hg (P < .05 for all). Similar findings were seen for diastolic variables. There were significant correlations between several systolic and diastolic variables in multiple directions and LV pre-A. On multivariate analysis, the independent predictors of systolic and diastolic speckle-tracking parameters included LVEF and LV pre-A, depending on the specific parameter analyzed. CONCLUSIONS: In patients with preserved LVEF and cardiac disease, several systolic and diastolic myocardial mechanical parameters significantly correlate with LV filling pressure. These data highlight the notion that patients with preserved LVEF and elevated LV filling pressures have significant abnormalities in systolic function as detected by speckle imaging, findings that may challenge the concept of "isolated diastolic dysfunction." The extent of systolic and diastolic abnormalities in these patients may shed light on the mechanics of heart failure with preserved LVEF.


Asunto(s)
Presión Sanguínea/fisiología , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Diástole/fisiología , Ecocardiografía/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Contracción Miocárdica/fisiología , Programas Informáticos , Volumen Sistólico/fisiología , Sístole/fisiología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Anciano , Fenómenos Biomecánicos , Cateterismo Cardíaco , Ecocardiografía Doppler/métodos , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Disfunción Ventricular Izquierda/fisiopatología
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