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1.
Artículo en Inglés | MEDLINE | ID: mdl-39234660

RESUMEN

Mitral valve repair or replacement poses a potential risk of injury to the left circumflex coronary artery (LCx). Such injuries can arise from either direct LCx injury caused by encircling or transfixing stitches, or indirect occlusion resulting from the distortion of adjacent tissues. We provide and illustrate a representative image depicting LCx distortion. Additionally, we offer guidance to aid angiographers in comprehending the angiographic appearance and the underlying mechanism of occlusion.

3.
JACC Cardiovasc Interv ; 17(14): 1680-1690, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39048255

RESUMEN

BACKGROUND: Thromboembolic events, particularly strokes, remain a major complication of transcatheter aortic valve replacement (TAVR). Embolic protection devices have failed to show significant clinical benefit in large randomized clinical trials. Aortic wall thrombus (AWT) is often observed on multidetector computed tomography during TAVR work-up, but its prognostic significance is uncertain. OBJECTIVES: This study sought to evaluate the association between the presence of AWT and the incidence of thromboembolic outcomes in patients undergoing transfemoral (TF) TAVR for severe aortic stenosis. METHODS: This was a prospective cohort study of consecutive patients who underwent TF TAVR for severe aortic stenosis between January 2011 and April 2022. A dedicated scale (range: 0-10) was qualitatively used to assess AWT. The primary outcome was a composite of procedural thromboembolic events defined as ischemic stroke, blue toe syndrome, bowel ischemia, or other solid organ infarction. The secondary endpoints were ischemic strokes and procedural death. RESULTS: Of the 641 patients included, severe AWT (score ≥8) was identified in 73 (11.4%). The presence of severe AWT was strongly associated with an increase in the primary outcome (OR: 8.48; 95% CI: 3.36-21.40; P < 0.001). This relationship persisted following multivariable analysis, which adjusted for comorbidities and procedural characteristics. The presence of severe AWT was also found to be associated with an increased incidence of stroke and procedural death (OR: 5.66; 95% CI: 2.00-15.30; P = 0.002 and OR: 4.66; 95% CI: 1.80-11.30; P = 0.002, respectively). CONCLUSIONS: The presence of severe AWT on preprocedural multidetector computed tomography is strongly associated with thromboembolic complications including stroke and mortality after TF TAVR.


Asunto(s)
Estenosis de la Válvula Aórtica , Arteria Femoral , Índice de Severidad de la Enfermedad , Tromboembolia , Trombosis , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Femenino , Masculino , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/mortalidad , Estudios Prospectivos , Factores de Riesgo , Anciano , Arteria Femoral/diagnóstico por imagen , Trombosis/diagnóstico por imagen , Trombosis/etiología , Trombosis/mortalidad , Trombosis/epidemiología , Resultado del Tratamiento , Tromboembolia/etiología , Tromboembolia/diagnóstico por imagen , Tromboembolia/mortalidad , Tromboembolia/prevención & control , Incidencia , Medición de Riesgo , Factores de Tiempo , Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Tomografía Computarizada Multidetector , Cateterismo Periférico/efectos adversos , Cateterismo Periférico/mortalidad , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/mortalidad , Punciones
5.
J Acoust Soc Am ; 155(2): 1297-1307, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38349806

RESUMEN

This paper presents a numerical framework for designing diffuse fields in rooms of any shape and size, driven at arbitrary frequencies. That is, we aim at overcoming the Schroeder frequency limit for generating diffuse fields in an enclosed space. We formulate the problem as a Tikhonov regularized inverse problem and propose a low-rank approximation of the spatial correlation that results in significant computational gains. Our approximation is applicable to arbitrary sets of target points and allows us to produce an optimal design at a computational cost that grows only linearly with the (potentially large) number of target points. We demonstrate the feasibility of our approach through numerical examples where we approximate diffuse fields at frequencies well below the Schroeder limit.

6.
BMC Cardiovasc Disord ; 24(1): 117, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373881

RESUMEN

BACKGROUND: To determine the prognostic value of cumulative calcification score of coronary artery calcification (CAC), thoracic aortic calcification (TAC) and aortic valve calcification (AVC) in acute ST segment elevation myocardial infarction (STEMI) patients. METHODS: This was a retrospective, single-center cohort study. A total of 332 STEMI patients who received primary percutaneous coronary intervention (PPCI) were enrolled in this study between January 2010 to October 2018. We assessed the calcification in the left anterior descending branch (LAD), left circumflex branch (LCX), right coronary artery (RCA), thoracic aorta, and aortic valve. Calcification of each part was counted as 1 point, and the cumulative calcification score was calculated as the sum of all points. The primary endpoint was all-cause mortality. Multivariate Cox proportional hazards models were used to determine association of cumulative calcification score with end points. The performance of the score was evaluated by receiver operating characteristic (ROC) curve analysis and absolute net reclassification improvement (NRI), compared with the Global Registry of Acute Coronary Events (GRACE) risk score. RESULTS: The overall population's calcification score was 2.0 ± 1.6. During a mean follow-up time of 69.8 ± 29.3 months, the all-cause mortality rate was 12.1%. Kaplan-Meier curve showed that the score was significantly associated with mortality (log-rank p < 0.001). The multivariable Cox proportional hazard analyses showed that a calcification score of 4-5 was independently associated with all-cause death in STEMI patients [hazard ratio (HR) = 2.32, 95% confidence interval (CI): 1.01-5.31, p = 0.046]. The area under the ROC curve (AUC) of the calcification score was 0.67 (95% CI: 0.61-0.72), and the AUC of the GRACE score was 0.80 (95% CI: 0.75-0.84). There was no statistical difference in the predictive value between both scores for 3-year mortality in STEMI patients after PPCI (p = 0.06). Based on the NRI analysis, the calcification score showed better risk classification compared with the GRACE score (absolute NRI = 6.63%, P = 0.027). CONCLUSION: The cumulative calcification score is independently associated with the long-term prognosis of STEMI patients after PPCI.


Asunto(s)
Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Estudios de Cohortes , Estudios Retrospectivos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Factores de Riesgo , Pronóstico , Arritmias Cardíacas/complicaciones , Intervención Coronaria Percutánea/efectos adversos , Medición de Riesgo
12.
Cardiovasc Diagn Ther ; 12(2): 220-228, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35433343

RESUMEN

Background: In the observational SUPER-MIMI study, a minimalist immediate mechanical intervention (MIMI) technique-which involves restoring blood flow in the acute phase and postponing stenting-was shown to be safe and effective among patients with a high thrombotic burden after ST-segment elevation myocardial infarction (STEMI). We aim to assess whether a non-stenting strategy after a SUPER-MIMI strategy was safe at 4-year follow-up in patients enrolled in the SUPER-MIMI study who were not stented. Methods: This prospective cohort study assessed the long-term outcomes of a subgroup of patients included in the SUPER-MIMI study. Results: Among the 155 patients enrolled in the SUPER-MIMI study, 57 patients (36.8%) benefited from a conservative management (without stenting or balloon angioplasty) and were included in the current substudy. The mean duration of follow-up was 4.1±1.0 years. Four patients (7.0%) presented definite culprit lesion re-thrombosis, all of which occurred in the right coronary artery. The re-thrombosis rate appeared to be higher among patients with larger vessels: 2.9%, 8.3%, and 28.6% in arteries with diameters of 3-<4, 4-<5, and ≥5 mm, respectively. The overall rate of target lesion revascularization was 10.5%. There was one cardiac death and three rehospitalizations for heart failure. Overall, 82.5% of patients remained event free at a mean of 4.1±1.0 years. Conclusions: Conservative management of non-stenotic culprit lesions after a SUPER-MIMI strategy was associated with a high rate of re-thrombosis, particularly in patients with large coronary arteries.

13.
J Insect Physiol ; 136: 104348, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34906562

RESUMEN

Within the context of climate change, winter temperatures at high latitudes are predicted to rise faster than summer temperatures. This phenomenon is expected to negatively affect the diapause performance and survival of insects, since they largely rely on low temperatures to lower their metabolism and preserve energy. However, some insects like honeybees, remain relatively active during the winter and elevate their metabolic rate to produce endothermic heat when temperatures drop. Warming winters are thus expected to improve overwintering performance of honeybees. In order to verify this hypothesis, for two consecutive years, we exposed honeybee colonies to either a mild or cold winter. We then monitored the influence of wintering conditions on several parameters of honeybee overwintering physiology, such as levels of the cryoprotectant glycerol, expression levels of immune and antioxidant genes, and genes encoding multifunctional proteins, including vitellogenin, which promotes bee longevity. Winter conditions had no effect on the expression of antioxidant genes, and genes related to immunity were not consistently affected. However, mild winters were consistently associated with a lower investment in glycerol synthesis and a higher expression of fat body genes, especially apidaecin and vitellogenin. Finally, while we found that viral loads generally decreased through the winter, this trend was more pronounced under mild winter conditions. In conclusion, and without considering how warming temperatures might affect other aspects of honeybee biology before overwintering, our data suggest that warming temperatures will likely benefit honeybee vitality by notably reducing their viral loads over the winter.


Asunto(s)
Virosis , Vitelogeninas , Animales , Abejas , Glicerol , Estaciones del Año , Temperatura , Vitelogeninas/genética
16.
Ultramicroscopy ; 227: 113200, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33581922

RESUMEN

Scanning Electron Microscopes (SEMs) often generate images with a shaded appearance which gives a natural 3D impression. Ergo, quite a few methods to reconstruct the 3D surface topography from these using shape-from-shading methods are available in the literature. Here, a novel approach is discussed which uses BackScatter Electron (BSE) images from multiple detectors to reconstruct the topography. Classically, algorithms exist which resort to a quad-BSE detector setup. However, other detector configurations are often found in SEMs. A set of images of these non-conforming detectors still contains enough information to allow for reconstruction, but requires a more general algorithm to do so. This article discusses a method based on a modal decomposition of the principal image components. The resulting method is shown to be efficient and independent of the number of detectors or their orientation. In fact, the orientation is identified as part of the algorithm and thus requires very little calibration.

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