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1.
Radiology ; 312(2): e232972, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-39189899

RESUMEN

Background Field-cycling imaging (FCI) is a new technology developed at the University of Aberdeen that measures change in T1 relaxation time constant of tissues over a range of low magnetic field strengths (0.2-200 mT) by rapidly switching between different fields during the pulse sequence. This provides new sources of contrast, including some invisible to clinical MRI scanners, and may be a useful alternative imaging modality for stroke. Purpose To test whether a prototype whole-body FCI scanner can be used to identify infarct regions in patients with subacute ischemic stroke. Materials and Methods This prospective study screened consecutive adult patients admitted to a single center stroke unit from February 2018 to March 2020 and April to December 2021. Included participants with confirmed ischemic stroke underwent FCI 1-6 days after ictus. FCI scans were obtained at four to six evolution fields between 0.2 mT and 0.2 T, with five evolution times from 5 to 546 msec. T1 maps were generated. The Wilcoxon signed-rank test was used to compare infarct region and contralateral unaffected brain, and Spearman rank correlation was used to examine associations between infarct to contralateral tissue contrast ratio and field strengths. Two independent readers blinded to clinical images rated the FCI scans. Results Nine participants (mean age, 62 years ± 16 [SD]; all male) successfully completed FCI. FCI scans below 0.2 T exhibited hyperintense T1 regions corresponding to the infarct region identified at baseline imaging, visually confirmed with 86% interrater agreement (Cohen κ = 0.69). Infarct to contralateral tissue contrast ratio increased as magnetic field decreased between 0.2 mT and 0.2 T (r[24] = -0.68; P < .001). T1 dispersion slopes differed between infarct and unaffected tissues (median, 0.23 [IQR, 0.18-0.37] vs 0.35 [IQR, 0.27-0.43]; P = .03). Conclusion Whole-brain FCI can be used to identify subacute ischemic stroke by T1 relaxation mechanisms at field strengths as low as 0.2 mT. Research Registry no. 1813 Published under a CC BY 4.0 license. Supplemental material is available for this article.


Asunto(s)
Accidente Cerebrovascular Isquémico , Imagen por Resonancia Magnética , Humanos , Masculino , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Estudios Prospectivos , Femenino , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Anciano , Encéfalo/diagnóstico por imagen
2.
J Am Heart Assoc ; 13(15): e034086, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39041603

RESUMEN

BACKGROUND: Detailed visualization and precise measurements of aortic valve dimensions are critical for the success of transcatheter aortic valve implantation and for the prevention of complications. Currently, multislice computed tomography is the gold standard for assessment of the aortic annulus and surrounding structures to determine the prosthesis size. New technologies such as virtual reality (VR) not only enable 3-dimensional (3D) visualization with the potential to improve understanding of anatomy and pathology but also allow measurements in 3D. This study aims to investigate the feasibility, accuracy, and reproducibility of VR for the visualization of the aortic valve, the surrounding structures, and its role in preprocedural sizing for transcatheter aortic valve implantation. METHODS AND RESULTS: Based on the preprocedural multislice computed tomography data, 3mensio measurements and 3D visualizations and measurements using VR software were performed retrospectively on 60 consecutive patients who underwent transcatheter aortic valve implantation at our heart center. There were no significant differences but strong correlations between the VR measurements compared with those performed with the 3mensio software. Furthermore, excellent or good intra- and interobserver reliability could be demonstrated for all values. In a structured questionnaire, users reported that VR simplified anatomical understanding, improved 3D comprehension of adjacent structures, and was associated with very good self-perceived depth perception. CONCLUSIONS: The use of VR for preprocedural transcatheter aortic valve implantation sizing is feasible and has precise and reproducible measurements. In addition, 3D visualization improves anatomical understanding and orientation. To evaluate the potential benefits of 3D visualization for planning further cardiovascular interventions, research in this field is needed.


Asunto(s)
Estenosis de la Válvula Aórtica , Válvula Aórtica , Estudios de Factibilidad , Prótesis Valvulares Cardíacas , Imagenología Tridimensional , Tomografía Computarizada Multidetector , Reemplazo de la Válvula Aórtica Transcatéter , Realidad Virtual , Humanos , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Reproducibilidad de los Resultados , Masculino , Femenino , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Anciano de 80 o más Años , Anciano , Estudios Retrospectivos , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Diseño de Prótesis , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador
3.
Artículo en Inglés | MEDLINE | ID: mdl-38943384

RESUMEN

BACKGROUND: Data on the effect of transcatheter aortic valve implantation (TAVI) on peripheral microcirculation are limited. OBJECTIVE: The aim of this study is to evaluate peripheral microvascular tissue saturation (StO2) before and after TAVI in relation to central and peripheral hemodynamics, cardiac and renal function. METHODS: In this single-center prospective study, patients with severe aortic stenosis (sAS) scheduled for TAVI or cardiac catheterization (control) were assessed before and up to five days after the procedure. Cardiac function including cardiac output (CO) was assessed by echocardiography. Brachial (bBP) and central blood pressure (cBP), ankle brachial index (ABI), and parameters of arterial stiffness, including augmentation pressure (AP) and augmentation index adjusted for heart rate (AIx@HR75) were measured to assess hemodynamic changes. StO2 was measured in all extremities using a near-infrared spectroscopy (NIRS) camera. Renal function was measured by creatinine levels. RESULTS: 26 patients underwent TAVI and 11 patients served as control. Cardiac output was significantly increased, whereas hemodynamic parameters and peripheral StO2 were significantly decreased after TAVI. At follow-up, StO2 returned to baseline values. Changes in StO2 were negatively related to creatinine levels. CONCLUSION: Transcatheter aortic valve implantation causes a temporary decrease in microvascular tissue saturation that is associated with renal function.

4.
Magn Reson Med ; 92(4): 1683-1697, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38703028

RESUMEN

PURPOSE: In this work, the use of joint Total Generalized Variation (TGV) regularization to improve Multipool-Lorentzian fitting of chemical exchange saturation transfer (CEST) Spectra in terms of stability and parameter signal-to-noise ratio (SNR) was investigated. THEORY AND METHODS: The joint TGV term was integrated into the nonlinear parameter fitting problem. To increase convergence and weight the gradients, preconditioning using a voxel-wise singular value decomposition was applied to the problem, which was then solved using the iteratively regularized Gauss-Newton method combined with a Primal-Dual splitting algorithm. The TGV method was evaluated on simulated numerical phantoms, 3T phantom data and 7T in vivo data with respect to systematic errors and robustness. Three reference methods were also implemented: The standard nonlinear fitting, a method using a nonlocal-means filter for denoising and the pyramid scheme, which uses downsampled images to acquire accurate start values. RESULTS: The proposed regularized fitting method showed significantly improved robustness (compared to the reference methods). In testing, over a range of SNR values the TGV fit outperformed the other methods and showed accurate results even for large amounts of added noise. Parameter values found were closer or comparable to the ground truth. For in vivo datasets, the added regularization increased the parameter map SNR and prevented instabilities. CONCLUSION: The proposed fitting method using TGV regularization leads to improved results over a range of different data-sets and noise levels. Furthermore, it can be applied to all Z-spectrum data, with different amounts of pools, where the improved SNR and stability can increase diagnostic confidence.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Fantasmas de Imagen , Relación Señal-Ruido , Imagen por Resonancia Magnética/métodos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Encéfalo/diagnóstico por imagen , Simulación por Computador , Reproducibilidad de los Resultados
5.
Front Cardiovasc Med ; 11: 1328906, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38596690

RESUMEN

Background: Understanding complex cardiac anatomy is essential for percutaneous left atrial appendage (LAA) closure. Conventional multi-slice computed tomography (MSCT) and transesophageal echocardiography (TEE) are now supported by advanced 3D printing and virtual reality (VR) techniques for three-dimensional visualization of volumetric data sets. This study aimed to investigate their added value for LAA closure procedures. Methods: Ten patients scheduled for interventional LAA closure were evaluated with MSCT and TEE. Patient-specific 3D printings and VR models were fabricated based on MSCT data. Ten cardiologists then comparatively assessed LAA anatomy and its procedure relevant surrounding structures with all four imaging modalities and rated their procedural utility on a 5-point Likert scale questionnaire (from 1 = strongly agree to 5 = strongly disagree). Results: Device sizing was rated highest in MSCT (MSCT: 1.9 ± 0.8; TEE: 2.6 ± 0.9; 3D printing: 2.5 ± 1.0; VR: 2.5 ± 1.1; p < 0.01); TEE, VR, and 3D printing were superior in the visualization of the Fossa ovalis compared to MSCT (MSCT: 3.3 ± 1.4; TEE: 2.2 ± 1.3; 3D printing: 2.2 ± 1.4; VR: 1.9 ± 1.3; all p < 0.01). The major strength of VR and 3D printing techniques was a superior depth perception (VR: 1.6 ± 0.5; 3D printing: 1.8 ± 0.4; TEE: 2.9 ± 0.7; MSCT: 2.6 ± 0.8; p < 0.01). The visualization of extracardiac structures was rated less accurate in TEE than MSCT (TEE: 2.6 ± 0.9; MSCT: 1.9 ± 0.8, p < 0.01). However, 3D printing and VR insufficiently visualized extracardiac structures in the present study. Conclusion: A true 3D visualization in VR or 3D printing provides an additional value in the evaluation of the LAA for the planning of percutaneous closure. In particular, the superior perception of depth was seen as a strength of a 3D visualization. This may contribute to a better overall understanding of the anatomy. Clinical studies are needed to evaluate whether a more comprehensive understanding through advanced multimodal imaging of patient-specific anatomy using VR may translate into improved procedural outcomes.

6.
Interv Cardiol ; 19: e01, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38464494

RESUMEN

Optimised implantation depth (OID) is crucial to obtain the best haemodynamic and clinical outcome during transcatheter heart valve (THV) deployment. OID ensures a better haemodynamic profile and is associated with a potential reduction in permanent pacemaker implantations, both of which are important during transcatheter aortic valve replacement (TAVR). Apart from patient-related anatomic conditions, many factors, such as THV and wire selection, as well as implantation strategies, can be controlled by the operator and facilitate the implantation process. However, there are only limited data dealing with predictors for OID. Therefore, the aim of this review was to outline factors and tools that might influence the final implantation depth during TAVR procedures, potentially influencing the outcome.

7.
Stroke ; 55(4): 1006-1014, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38445467

RESUMEN

BACKGROUND: Inflammatory type focal cerebral arteriopathy (FCA-i) in the anterior circulation (AC) is well characterized, and the focal cerebral arteriopathy severity score (FCASS) reflects the severity of the disease. We identified cases of FCA-i in the posterior circulation (PC) and adapted the FCASS to describe these cases. METHODS: In this comparative cohort study, patients from the Swiss NeuroPaediatric Stroke Registry with ischemic stroke due to FCA-i between January 2000 and December 2018 were analyzed. A comparison between PC and AC cases regarding pediatric National Institutes of Health Stroke Scale score and pediatric stroke outcome measure and FCASS was performed. We estimated infarct size by the modified pediatric Alberta Stroke Program Early Computed Tomography Score in children with AC stroke and the adapted Bernese posterior diffusion-weighted imaging score in the PC. RESULTS: Thirty-five children with a median age of 6.3 (interquartile range, 2.7-8.2 [95% CI, 0.9-15.6]; 20 male; 57.1%) years with FCA-i were identified. The total incidence rate was 0.15/100 000/year (95% CI, 0.11-0.21). Six had PC-FCA-i. Time to final FCASS was longer in the PC compared with AC; the evolution of FCASS did not differ. Initial pediatric National Institutes of Health Stroke Scale score was higher in children with FCA-i in the PC with a median of 10.0 (interquartile range, 5.75-21.0) compared with 4.5 (interquartile range, 2.0-8.0) in those with AC-FCA-i. Different from the anterior cases, PC infarct volume did not correlate with higher discharge, maximum, or final FCASS scores (Pearson correlation coefficient [r], 0.25, 0.35, and 0.54). CONCLUSIONS: FCA-i also affects the PC. These cases should be included in future investigations into FCA-i. Although it did not correlate with clinical outcomes in our cohort, the modified FCASS may well serve as a marker for the evolution of the arteriopathy in posterior FCA-i.


Asunto(s)
Enfermedades Arteriales Cerebrales , Trastornos Cerebrovasculares , Accidente Cerebrovascular , Humanos , Niño , Masculino , Estudios de Cohortes , Trastornos Cerebrovasculares/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Enfermedades Arteriales Cerebrales/diagnóstico por imagen , Enfermedades Arteriales Cerebrales/epidemiología , Enfermedades Arteriales Cerebrales/complicaciones , Infarto
8.
EMBO Rep ; 25(3): 1106-1129, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38308064

RESUMEN

Herpesviruses modulate immune control to secure lifelong infection. The mechanisms Human Cytomegalovirus (HCMV) employs in this regard can reveal unanticipated aspects of cellular signaling involved in antiviral immunity. Here, we describe a novel relationship between the TGF-ß family cytokine BMP9 and HCMV infection. We identify a cross-talk between BMP9-induced and IFN receptor-mediated signaling, showing that BMP9 boosts the transcriptional response to and antiviral activity of IFNß, thereby enhancing viral restriction. We also show that BMP9 is secreted by human fibroblasts upon HCMV infection. However, HCMV infection impairs BMP9-induced enhancement of the IFNß response, indicating that this signaling role of BMP9 is actively targeted by HCMV. Indeed, transmembrane proteins US18 and US20, which downregulate type I BMP receptors, are necessary and sufficient to cause inhibition of BMP9-mediated boosting of the antiviral response to IFNß. HCMV lacking US18 and US20 is more sensitive to IFNß. Thus, HCMV has a mutually antagonistic relationship with BMP9, which extends the growing body of evidence that BMP signaling is an underappreciated modulator of innate immunity in response to viral infection.


Asunto(s)
Factor 2 de Diferenciación de Crecimiento , Inmunidad Innata , Humanos , Citocinas/metabolismo , Citomegalovirus/metabolismo , Factor 2 de Diferenciación de Crecimiento/metabolismo , Transducción de Señal
9.
Front Cardiovasc Med ; 10: 1188571, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37727301

RESUMEN

Background and aims: The complex and highly variable three-dimensional anatomy of the left atrial appendage (LAA) makes planning and device sizing for interventional occlusion procedures (LAAC) challenging. Several imaging modalities [e.g. echocardiography, multi-slice computed tomography (MSCT)] are used for this purpose. Virtual reality (VR) is an emerging imaging technique to immerse into a three-dimensional left atrium and appendage, offering unprecedented options of visualization and measurement. This study aimed to investigate the feasibility, accuracy and reproducibility of visualizing the LAA in VR for preprocedural planning of LAAC. Methods and results: Twenty-one patients (79 ± 7 years, 62% male) who underwent LAAC at University Hospital Düsseldorf were included in our study. A dedicated software generated three-dimensional VR models from preprocedural MSCT imaging data. Conventional measurements of LAA dimensions (ostium, landing zone and depth) using a commercially available software were compared to measurements in VR: MSCT and VR ostium min. (r = 0.93), max. (r = 0.80) and mean (r = 0.88, all p < 0.001) diameters as well as landing zone (LZ) min. (r = 0.84), max. (r = 0.86) and mean diameters (r = 0.90, all p < 0.001) showed strong correlations. Three-dimensional orientation was judged superior by physicians in VR compared to MSCT (p < 0.05). Conclusion: Virtual reality visualization of the left atrium and appendage based on MSCT data is feasible and allows precise and reproducible measurements in planning of LAA occlusion procedures with enhanced 3D orientation. Further studies need to explore additional benefits of three-dimensional visualization for operators in preprocedural planning.

10.
Nanomaterials (Basel) ; 13(9)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37177101

RESUMEN

Structural anti-reflective coating and bactericidal surfaces, as well as many other effects, rely on high-aspect-ratio (HAR) micro- and nanostructures, and thus, are of great interest for a wide range of applications. To date, there is no widespread fabrication of dense or isolated HAR nanopillars based on UV nanoimprint lithography (UV-NIL). In addition, little research on fabricating isolated HAR nanopillars via UV-NIL exists. In this work, we investigated the mastering and replication of HAR nanopillars with the smallest possible diameters for dense and isolated arrangements. For this purpose, a UV-based nanoimprint lithography process was developed. Stability investigations with capillary forces were performed and compared with simulations. Finally, strategies were developed in order to increase the stability of imprinted nanopillars or to convert them into nanoelectrodes. We present UV-NIL replication of pillars with aspect ratios reaching up to 15 with tip diameters down to 35 nm for the first time. We show that the stability could be increased by a factor of 58 when coating them with a 20 nm gold layer and by a factor of 164 when adding an additional 20 nm thick layer of SiN. The coating of the imprints significantly improved the stability of the nanopillars, thus making them interesting for a wide range of applications.

11.
Am J Cardiol ; 197: 87-92, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37137798

RESUMEN

Sex-specific thresholds of aortic valve calcification (AVC) correlate with aortic stenosis (AS) and may complement echocardiography to determine AS severity. Importantly, current guideline-recommended thresholds of AVC scores derived by multislice computed tomography do not distinguish between bicuspid and tricuspid aortic valves. The objective of this study was to evaluate the sex-specific differences in the amount of AVC in patients with severe AS and tricuspid (TAV) versus bicuspid (BAV) aortic valve morphologies, retrospectively evaluated by 2 tertiary care institutions. The inclusion criteria comprised patients with severe AS and a left ventricular ejection fraction ≥50% and suitable imaging examinations. The study included 1,450 patients (723 men; 49.9%) with severe AS, including 1,335 patients with TAV (92.1%) and 115 with BAV (17.9%). The calculated Agatston score was higher in BAV patients (men: BAV 4,358 [2,644 to 6,005] AU vs TAV 2,643 [1,727 to 3,794] AU, p <0.01; women: BAV 2,174 [1,330 to 4,378] AU vs TAV 1,703 [964 to 2,534] AU, p <0.01), also when indexed for valve dimensions and body surface area (men: BAV 2,227 [321 to 3,105] AU/m2 vs TAV 1,333 [872 to 1,913] AU/m2, p <0.01; women: BAV 1,326 [782 to 2,148] AU/m2 vs TAV 930 [546 to 1,456] AU/m2, p <0.01). Differences between the BAV- and TAV-derived Agatston score was more prominent in concordant severe AS. In conclusion, sex-specific Agatston scores in severe AS were approximately 1/3 higher in patients with BAV than in patients with TAV for both women and men. Optimal AVC thresholds should be adjusted for BAV, also respecting considerable prognostic implications.


Asunto(s)
Estenosis de la Válvula Aórtica , Válvula Aórtica , Masculino , Humanos , Femenino , Válvula Aórtica/diagnóstico por imagen , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular Izquierda , Estenosis de la Válvula Aórtica/diagnóstico por imagen
12.
Hellenic J Cardiol ; 74: 1-7, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37119968

RESUMEN

OBJECTIVES: Left ventricular reverse remodeling (LVRR) is associated with improved outcome in patients with heart failure. Factors associated with and predictive of LVRR in patients with low-flow low-gradient aortic stenosis (LFLG AS) after transcatheter aortic valve implantation (TAVI) and its impact on outcome were assessed. METHODS: Pre- and postprocedural left ventricular (LV) function and volume were investigated in 219 patients with LFLG. LVRR was defined as an absolute increase of ≥10% in LV ejection fraction (LVEF) and reduction of ≥15% in LV end-systolic volume (LVESV). The primary endpoint was the combination of all-cause mortality and rehospitalization for heart failure. RESULTS: The mean LVEF was 35.0 ± 10.0%, with a stroke volume index (SVI) of 25.9 ± 6.0 mL/m2 and LVESV of 94.04 ± 46.0 mL. At a median of 5.2 months (interquartile range, 2.7-8.1 months), 77.2% (n = 169) of the patients showed echocardiographic evidence of LVRR. A multivariate model revealed three independent factors for LVRR after TAVI: SVI of <25 mL/m2 (hazard ratio [HR], 2.31; 95% confidence interval [CI], 1.08-3.58; p < 0.01), LVEF of <30% (HR, 2.76; 95% CI, 1.53-2.91; p < 0.01), and valvulo-arterial impedance (Zva) of <5 mmHg/mL/m2 (HR, 5.36; 95% CI, 1.80-15.98; p < 0.01). Patients without evidence of LVRR showed a significantly higher incidence of the 1-year combined endpoint (32 [64.0%] vs. 75 [44.4%], p < 0.01). CONCLUSIONS: The majority of patients with LFLG AS show LVRR after TAVI, which is associated with favorable outcomes. An SVI of <25 mL/m2, LVEF of <30%, and Zva < 5mmHg/mL/m2 represent predictors of LVRR.


Asunto(s)
Estenosis de la Válvula Aórtica , Insuficiencia Cardíaca , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento , Estudios Retrospectivos , Función Ventricular Izquierda , Volumen Sistólico , Insuficiencia Cardíaca/complicaciones , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Remodelación Ventricular , Índice de Severidad de la Enfermedad
13.
EuroIntervention ; 19(2): e176-e187, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37013922

RESUMEN

BACKGROUND: Reducing rates of permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation (TAVI) is important for achieving the best procedural outcomes. The cusp overlap technique (COT) implements procedural steps including an overlap angulation of the right and left coronary cusp to mitigate this complication. AIMS: We investigated the incidence of PPI and complication rates following the COT compared to the standard three-cusp implantation technique (3CT) in an all-comers cohort. METHODS: A total of 2,209 patients underwent TAVI with the self-expanding Evolut platform from January 2016 to April 2022 at five sites. Baseline, procedural and in-hospital outcome characteristics were compared for both techniques before and after one-to-one propensity score matching. RESULTS: A total of 1,151 patients were implanted using the 3CT and 1,058 using the COT. At discharge, the rates of PPI (17.0 vs 12.3%; p=0.002) and moderate/severe paravalvular regurgitation (4.6% vs 2.4%; p=0.006) were significantly reduced with the COT compared with 3CT within the unmatched cohort. Overall procedural success and complication rates were similar; major bleeding was less common in the COT group (7.0% vs 4.6%; p=0.020). These results remained consistent after propensity score matching. In multivariable logistic regression analysis, right bundle branch block (odds ratio [OR] 7.19, 95% confidence interval [CI]: 5.18-10.0; p<0.001) and diabetes mellitus (OR 1.38, 95% CI: 1.05-1.80; p=0.021) emerged as predictors of PPI, whereas the COT (OR 0.63, 95% CI: 0.49-0.82; p<0.001) was protective. CONCLUSIONS: The introduction of the COT was associated with a significant and relevant reduction of PPI and paravalvular regurgitation rates without an increase in complication rates.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Marcapaso Artificial , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Complicaciones Posoperatorias/epidemiología , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Resultado del Tratamiento , Diseño de Prótesis , Factores de Riesgo
14.
NMR Biomed ; 36(8): e4927, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36932842

RESUMEN

Intravoxel incoherent motion (IVIM) imaging and diffusion tensor imaging (DTI) facilitate noninvasive quantification of tissue perfusion and diffusion. Both are promising biomarkers in various diseases and a combined acquisition is therefore desirable. This comes with challenges, including noisy parameter maps and long scan times, especially for the perfusion fraction f and pseudo-diffusion coefficient D*. A model-based reconstruction has the potential to overcome these challenges. As a first step, our goal was to develop a model-based reconstruction framework for IVIM and combined IVIM-DTI parameter estimation. The IVIM and IVIM-DTI models were implemented in the PyQMRI model-based reconstruction framework and validated with simulations and in vivo data. Commonly used voxel-wise nonlinear least-squares fitting was used as the reference. Simulations with the IVIM and IVIM-DTI models were performed with 100 noise realizations to assess accuracy and precision. Diffusion-weighted data were acquired for IVIM reconstruction in the liver (n = 5), as well as for IVIM-DTI in the kidneys (n = 5) and lower-leg muscles (n = 6) of healthy volunteers. The median and interquartile range (IQR) values of the IVIM and IVIM-DTI parameters were compared to assess bias and precision. With model-based reconstruction, the parameter maps exhibited less noise, which was most pronounced in the f and D* maps, both in the simulations and in vivo. The bias values in the simulations were comparable between model-based reconstruction and the reference method. The IQR was lower with model-based reconstruction compared with the reference for all parameters. In conclusion, model-based reconstruction is feasible for IVIM and IVIM-DTI and improves the precision of the parameter estimates, particularly for f and D* maps.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Humanos , Movimiento (Física) , Imagen de Difusión por Resonancia Magnética/métodos , Hígado/diagnóstico por imagen , Músculo Esquelético
15.
Clin Cardiol ; 46(1): 67-75, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36259730

RESUMEN

BACKGROUND: Despite major advances, transcatheter aortic valve replacement (TAVR) is still associated with procedure-specific complications. Although previous studies reported lower bleeding rates in patients receiving protamine for heparin reversal, the optimal protamine-to-heparin dosing ratio is unknown. HYPOTHESIS: The aim of this study was a comparison of two different heparin antagonization regimens for the prevention of bleeding complications after TAVR. METHODS: The study included 1446 patients undergoing TAVR, of whom 623 received partial and 823 full heparin antagonization. The primary endpoint was a composite of 30-day mortality, life-threatening, and major bleeding. Safety endpoints included stroke and myocardial infarction at 30 days. RESULTS: Full antagonization of heparin resulted in lower rates of the primary endpoint as compared to partial heparin reversal (5.6% vs. 10.4%, p < .01), which was mainly driven by lower rates of life-threatening (0.5% vs. 1.6%, p = .05) and major bleeding (3.2% vs. 7.5%, p < .01). Moreover, the incidence of major vascular complications was significantly lower in patients with full heparin reversal (3.5% vs. 7.5%, p < .01). The need for red-blood-cell transfusion was lower in patients receiving full as compared to partial heparin antagonization (10.4% vs. 15.9%, p < .01). No differences were observed in the incidence of stroke and myocardial infarction between patients with full and partial heparin reversal (2.2% vs. 2.6%, p = .73 and 0.2% vs. 0.4%, p = .64, respectively). CONCLUSIONS: Full heparin antagonization resulted in significantly lower rates of life-threatening and major bleeding after TAVR as compared to partial heparin reversal. The occurrence of stroke and myocardial infarction was low and comparable between both groups.


Asunto(s)
Estenosis de la Válvula Aórtica , Infarto del Miocardio , Accidente Cerebrovascular , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Heparina/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Protaminas/efectos adversos , Factores de Riesgo , Resultado del Tratamiento , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/inducido químicamente , Infarto del Miocardio/prevención & control , Infarto del Miocardio/complicaciones , Válvula Aórtica/cirugía
16.
Hellenic J Cardiol ; 70: 1-9, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36538975

RESUMEN

OBJECTIVE: Several supra-annular self-expanding transcatheter systems are commercially available for transcatheter aortic valve implantation (TAVI). Comparative data in large-scale multicenter studies are scant. METHODS: This study included a total of 5175 patients with severe aortic stenosis undergoing TAVI with the ACURATE neo (n = 1095), Evolut R (n = 3365), or Evolut PRO (n = 715) by a transfemoral approach at five high-volume centers. Propensity score matching resulted in 654 triplets. Outcomes are reported according to the Valve Academic Research Consortium-3 (VARC-3) consensus. RESULTS: Moderate or severe paravalvular regurgitation (PVR) occurred significantly more often in the ACURATE neo group (5.2%) than in the Evolut R (1.8%) and Evolut PRO (3.3%) groups (p = 0.003). The rates of major vascular-/access-related complications (4.6%, 3.8%, and 5.0%; p = 0.56), type 3 or 4 bleeding (3.2%, 2.1%, and 4.1%; p = 0.12), and 30-day mortality (2.4%, 2.6%, and 3.7%; p = 0.40) were comparable. The rate of new permanent pacemaker implantation (PPI) was significantly lower in the ACURATE neo group (9.5%, 17.6%, and 16.8%; p < 0.001). Independent predictors for 2-year survival were a Society of Thoracic Surgeons (STS) risk score ≥5%, diabetes mellitus, a glomerular filtration rate <30 ml/min, baseline mean transvalvular gradient ≤ 30 mm Hg, treating center, and relevant PVR. CONCLUSION: In this multicenter study, TAVI with the ACURATE neo, Evolut R, or Evolut PRO was feasible and safe. The rate of relevant PVR was more frequent after the ACURATE neo implantation, with, however, lower rates of PPI. Two-year survival was mainly driven by baseline comorbidities.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Puntaje de Propensión , Diseño de Prótesis , Resultado del Tratamiento
17.
Front Cardiovasc Med ; 9: 847568, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36119734

RESUMEN

Background: The implantation depth (ID) is a critical condition for optimal hemodynamic and clinical outcomes in transcatheter aortic valve replacement (TAVR). The recently recommended cusp-overlap technique (COT) offers optimized fluoroscopic projections facilitating a precise ID. This single-center observational study aimed to investigate short-term clinical performance, safety, and efficacy outcomes in patients undergoing TAVR with self-expandable prostheses and application of COT in a real-world setting. Materials and methods: From September 2020 to April 2021, a total of 170 patients underwent TAVR with self-expandable devices and the application of COT, while 589 patients were treated from January 2016 to August 2020 with a conventional three-cusp coplanar view approach. The final ID and 30-day outcomes were compared after 1:1 propensity score matching, resulting in 150 patients in both cohorts. Results: The mean ID was significantly reduced in the COT cohort (-4.2 ± 2.7 vs. -4.9 ± 2.3 mm; p = 0.007) with an improvement of ID symmetry of less than 2 mm difference below the annular plane (47.3 vs. 57.3%; p = 0.083). The rate of new permanent pacemaker implantation (PPI) following TAVR was effectively reduced (8.0 vs. 16.8%; p = 0.028). While the fluoroscopy time decreased (18.4 ± 7.6 vs. 19.8 ± 7.6 min; p = 0.023), the dose area product increased in the COT group (4951 ± 3662 vs. 3875 ± 2775 Gy × cm2; p = 0.005). Patients implanted with COT had a shorter length of in-hospital stay (8.4 ± 4.0 vs. 10.3 ± 6.7 days; p = 0.007). Conclusion: Transcatheter aortic valve replacement using the cusp-overlap deployment technique is associated with an optimized implantation depth, leading to fewer permanent conduction disturbances. However, our in-depth analysis showed for the first time an increase of radiation dose due to extreme angulations of the gantry to obtain the cusp-overlap view.

18.
Catheter Cardiovasc Interv ; 100(5): 850-859, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35989489

RESUMEN

BACKGROUND: A significant number of patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) suffer from extra-aortic cardiac damage. Few studies have investigated strategies to quantify cardiac damage and stratify patients accordingly in different risk groups. The aim of this retrospective multicenter study was to provide a user-friendly simplified staging system based on the proposed classification system of Généreux et al. as a tool to evaluate the prognosis of patients undergoing TAVR more easily. Moreover, we analyzed changes in cardiac damage after TAVR. METHODS: We assessed cardiac damage in patients, who underwent TAVR at the Heart Center Bonn or Düsseldorf, using pre- and postprocedural transthoracic echocardiography. Patients were assigned to the staging system proposed by Généreux et al. according to the severity of their baseline cardiac damage. Based on the established system, we created a simplified staging system to facilitate improved applicability. Finally, we compared clinical outcomes between the groups and evaluated changes in cardiac damage after TAVR. RESULTS: A total of 933 TAVR patients were included in the study. We found a significant association between cardiac damage and 1-year all-cause mortality (stage 0: 0% vs. stage 1: 3% vs. stage 2: 6.6%; p < 0.009). In multivariate analysis, cardiac damage was an independent predictor of 1-year all-cause mortality (hazard ratio: 2.0, 95% confidence interval: 1.1-3.8; p = 0.03). CONCLUSIONS: In patients undergoing TAVR, cardiac damage is associated with enhanced mortality. A simplified staging system can help identify patients at high risk for an adverse outcome.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/etiología , Resultado del Tratamiento , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Factores de Riesgo , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
19.
J Clin Med ; 11(13)2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35807187

RESUMEN

Background: Cerebrovascular events (CVE) are feared complications following transcatheter aortic valve replacement (TAVR). We aimed to develop a new risk model for CVE prediction with the application of multimodal imaging. Methods: From May 2011 to August 2019, a total of 2015 patients underwent TAVR at our institution. The study cohort was subdivided into a derivation cohort (n = 1365) and a validation cohort (n = 650) for risk model development. Results: Of 2015 patients, 72 (3.6%) developed TAVR-related CVE. Pre-procedural factors of our risk model were history of prior CVE, a larger aortic valve area (≥0.55 cm2), a large aortic angulation (≥48.5°), and enhanced calcification of the right coronary cusp (≥447.2 AU), left ventricular outflow tract (≥262.4 AU), and ascending thoracic aorta (≥116.4 AU). Our risk model was superior for in-hospital CVE prediction following TAVR in the establishment cohort (AUC 0.73, 95% CI 0.66−0.80; p < 0.001) compared to other risk scores, such as the EuroSCORE II or the CHA2DS2-VASc score. Conclusions: Although CVE prediction in patients undergoing TAVR is challenging due to the complex nature of the TAVR procedure, our study highlights that multimodal imaging is a promising approach to generate a more accurate risk model for CVE prediction.

20.
J Cardiovasc Dev Dis ; 9(6)2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35735818

RESUMEN

Due to shortages of medical resources during the Coronavirus Disease 2019 (COVID-19) pandemic, an allocation algorithm for Transcatheter Aortic Valve Replacement (TAVR) was established. We investigated the impact on patient selection and procedural results. In total, 456 TAVR patients before (pre-COVID-19 group) and 456 TAVR patients after (COVID-19 group) the implementation of our allocation algorithm were compared. Concerning patient characteristics, the COVID-19 group revealed a higher rate of cardiac decompensations/cardiogenic shocks (10.5% vs. 1.3%; p < 0.001), severe angina pectoris (Canadian Cardiovascular Society (CCS) II, III and IV: 18.7% vs. 11.8%; p = 0.004), troponin elevation (>14 ng/L: 84.9% vs. 77%; p = 0.003) and reduced left ventricular ejection fraction (LVEF) (<45%: 18.9% vs. 12%; p = 0.006). Referring to procedural characteristics, more predilatations (46.3% vs. 35.1%; p = 0.001) and a longer procedural time (80.2 min (+/−29.4) vs. 66.9 min (+/−17.5); p < 0.001) were observed. The success rate was evenly high; no differences in safety parameters were reported. Examining the utilization of hospital resources, the COVID-19 group showed a shorter in-hospital stay (8.4 days (+/−5.9) vs. 9.5 days (+/−9.33); p = 0.041) and fewer TAVR patients were treated per month (39 (+/−4.55) vs. 46.11 (+/−7.57); p = 0.03). Our allocation algorithm supported prioritization of sicker patients with similar efficient and safe TAVR procedures. In-hospital stay could be shortened.

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