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1.
J Vet Cardiol ; 52: 35-42, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422726

RESUMO

INTRODUCTION: Small dogs with patent ductus arteriosus (PDA) may be unable to undergo transesophageal echocardiography (TEE) with traditional probes. OBJECTIVES: To report the utility of TEE using a microprobe in dogs weighing less than 4 kg diagnosed with PDA for determination of transcatheter procedural candidacy, device selection, and intraoperative procedural guidance. ANIMALS: Eight dogs weighing less than 4 kg diagnosed with PDA. MATERIALS AND METHODS: All dogs had standard transthoracic echocardiography and microprobe TEE imaging. The quality of TEE images was graded as optimal, adequate, or poor. The ability of TEE to assess PDA anatomy, determine procedural candidacy, provide procedural guidance, detect deployed devices, and assess residual flow was recorded. RESULTS: The median age of included dogs was 6.4 months (range: 3.2-15.7 months) and the median body weight was 2.2 kg (range: 1.4-3.8 kg). Microprobe TEE images were adequate or optimal in all dogs and were integral for guiding procedural candidacy decisions. Transcatheter procedures were not pursued in two dogs based on TEE images. In the other six dogs, TEE procedural guidance was useful during transvenous (n = 5) and transarterial (n = 1) PDA occlusion attempts. Each deployed device (n = 4) was easily detected with the TEE microprobe. Real-time confirmation of adequate device sizing and placement was possible prior to release and residual flow could be monitored after release. CONCLUSIONS: Transesophageal echocardiography using a microprobe in dogs weighing less than 4 kg diagnosed with PDA allowed for characterization of PDA anatomy and determination of transcatheter procedural candidacy. Microprobe TEE images were integral for PDA device selection and offered valuable intraoperative procedural guidance.


Assuntos
Cateterismo Cardíaco , Doenças do Cão , Permeabilidade do Canal Arterial , Ecocardiografia Transesofagiana , Animais , Cães , Permeabilidade do Canal Arterial/veterinária , Permeabilidade do Canal Arterial/cirurgia , Permeabilidade do Canal Arterial/diagnóstico por imagem , Ecocardiografia Transesofagiana/veterinária , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/cirurgia , Cateterismo Cardíaco/veterinária , Cateterismo Cardíaco/instrumentação , Feminino , Masculino
2.
Acta Trop ; 250: 107087, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061614

RESUMO

Triatomine insects are vectors of the protozoan parasite Trypanosoma cruzi- the causative agent of Chagas disease. Chagas disease is endemic to Latin America and the southern United States and can cause severe cardiac damage in infected mammals, ranging from chronic disease to sudden death. Identifying interactions among triatomines, T. cruzi discrete typing units (DTUs), and blood feeding hosts is necessary to understand parasite transmission dynamics and effectively protect animal and human health. Through manual insect trapping efforts, kennel staff collections, and with the help of a trained scent detection dog, we collected triatomines from 10 multi-dog kennels across central and south Texas over a one-year period (2018-2019) and tested a subset to determine their T. cruzi infection status and identify the primary bloodmeal hosts. We collected 550 triatomines, including Triatoma gerstaeckeri (n = 515), Triatoma lecticularia (n = 15), Triatoma sanguisuga (n = 6), and Triatoma indictiva (n = 2), with an additional 10 nymphs and 2 adults unable to be identified to species. The trained dog collected 42 triatomines, including nymphs, from areas not previously considered vector habitat by the kennel owners. Using qPCR, we found a T. cruzi infection prevalence of 47 % (74/157), with T. lecticularia individuals more likely to be infected with T. cruzi than other species. Infected insects harbored two T. cruzi discrete typing units: TcI (64 %), TcIV (23 %), and mixed TcI/TcIV infections (13 %). Bloodmeal host identification was successful in 50/149 triatomines, revealing the majority (74 %) fed on a dog (Canis lupus), with other host species including humans (Homo sapiens), raccoons (Procyon lotor), chickens (Gallus gallus), wild pig (Sus scrofa), black vulture (Coragyps atratus), cat (Felis catus), and curve-billed thrasher (Toxostoma curviostre). Given the frequency of interactions between dogs and infected triatomines in these kennel environments, dogs may be an apt target for future vector control and T. cruzi intervention efforts.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Animais , Cães , Humanos , Gatos , Trypanosoma cruzi/genética , Texas/epidemiologia , Insetos Vetores/parasitologia , Galinhas , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Doença de Chagas/parasitologia , Triatoma/parasitologia , Mamíferos
3.
J Vet Cardiol ; 51: 35-52, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38071799

RESUMO

The unique imaging capabilities of transesophageal echocardiography (TEE) make it a valuable tool for characterizing the structure and function of the heart and for providing procedural monitoring. With the creation of new devices and expansion of procedural options with increased applications, multiplanar and three-dimensional imaging with TEE can be essential for clinical decision making. A description of the indications and clinical application of TEE in animals while highlighting probe characteristics, limitations and patient safety are the focus of this review. The increased availability of three-dimensional imaging in smaller probes, advanced applications including photorealistic and fusion imaging, and the development of recommended standards for performing a comprehensive TEE imaging study including training guidelines may facilitate the use of TEE in the veterinary field.


Assuntos
Ecocardiografia Tridimensional , Ecocardiografia Transesofagiana , Animais , Ecocardiografia Transesofagiana/veterinária , Ecocardiografia Transesofagiana/métodos , Coração , Ecocardiografia Tridimensional/veterinária
4.
J Vet Cardiol ; 50: 1-16, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913604

RESUMO

INTRODUCTION: Cavalier King Charles Spaniels (CKCS) are predisposed to developing myxomatous mitral valve disease (MMVD). Dogs with stage B2 MMVD benefit from medication. OBJECTIVES: To develop (1) breed-specific cut-offs for individual screening tests and (2) predictive models utilizing physical examination (PE), ECG, radiograph, and blood-based biomarker variables in combination for identification of echocardiographic stage B2 MMVD in preclinical CKCS. ANIMALS: Adult, preclinical CKCS not receiving cardiac medications (N = 226). MATERIALS AND METHODS: Prospective, cross-sectional study. Enrolled CKCS underwent PE, ECG, radiography, Doppler blood pressure measurement, echocardiography, and biomarker testing. Dogs were grouped by MMVD stage using echocardiography only. The discriminatory ability of individual tests to identify stage B2 was assessed, and prediction models were developed using variables derived from four 'tests' (PE, ECG, radiography, and biomarkers). RESULTS: N-terminal pro-B-type natriuretic peptide (NT-proBNP) and radiographic vertebral heart size (VHS) had the best discriminatory ability of individual diagnostic tests to differentiate stage A/B1 CKCS from stage B2, with an area under the curve (AUC) of 0.855 and 0.843, respectively. An NT-proBNP ≥1138 pmol/L or a VHS ≥11.5 had high specificity for predicting stage B2 (90.1% and 90.6%, respectively). Prediction models incorporating variables from multiple tests had better discriminatory ability than single tests. The four-test prediction model had an AUC of 0.971. Three and two-test models had AUCs ranging between 0.925-0.959 and 0.895-0.949, respectively. CONCLUSIONS: Both NT-proBNP and VHS have good utility for predicting echocardiographic stage B2 MMVD in CKCS as individual tests. Prediction models incorporating multiple test variables have superior discriminatory ability.


Assuntos
Doenças do Cão , Doenças das Valvas Cardíacas , Cães , Animais , Valva Mitral , Estudos Prospectivos , Estudos Transversais , Doenças do Cão/diagnóstico por imagem , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/veterinária , Ecocardiografia/veterinária , Eletrocardiografia/veterinária , Radiografia , Exame Físico , Biomarcadores
5.
J Vet Cardiol ; 48: 31-36, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37379743

RESUMO

A three-year-old, spayed female, Bichon Frise was diagnosed with an anomalous origin of the left coronary artery from the pulmonary artery, a rare congenital coronary artery defect which has only been reported in two other dogs. Echocardiography was initially performed, though the final diagnosis was made with angiography and computed tomography angiography. An extensive network of collateral coronary circulation allowed for communication between the dilated, tortuous right coronary artery, and the anomalous left coronary artery. Though collateral circulation likely prolonged the patient's life, it is suspected that coronary steal phenomenon and chronic myocardial ischemia ultimately led to fatal ventricular arrhythmias. The dog died suddenly at the age of six, three years after initial diagnosis.


Assuntos
Anomalias dos Vasos Coronários , Doenças do Cão , Cães , Feminino , Animais , Vasos Coronários/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/anormalidades , Circulação Colateral , Coração , Circulação Coronária , Anomalias dos Vasos Coronários/diagnóstico por imagem , Anomalias dos Vasos Coronários/veterinária , Angiografia Coronária/métodos , Doenças do Cão/diagnóstico por imagem
6.
Nature ; 618(7964): 270-275, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225995

RESUMO

The gravitational pressure in many astrophysical objects exceeds one gigabar (one billion atmospheres)1-3, creating extreme conditions where the distance between nuclei approaches the size of the K shell. This close proximity modifies these tightly bound states and, above a certain pressure, drives them into a delocalized state4. Both processes substantially affect the equation of state and radiation transport and, therefore, the structure and evolution of these objects. Still, our understanding of this transition is far from satisfactory and experimental data are sparse. Here we report on experiments that create and diagnose matter at pressures exceeding three gigabars at the National Ignition Facility5 where 184 laser beams imploded a beryllium shell. Bright X-ray flashes enable precision radiography and X-ray Thomson scattering that reveal both the macroscopic conditions and the microscopic states. The data show clear signs of quantum-degenerate electrons in states reaching 30 times compression, and a temperature of around two million kelvins. At the most extreme conditions, we observe strongly reduced elastic scattering, which mainly originates from K-shell electrons. We attribute this reduction to the onset of delocalization of the remaining K-shell electron. With this interpretation, the ion charge inferred from the scattering data agrees well with ab initio simulations, but it is significantly higher than widely used analytical models predict6.

7.
J Vet Cardiol ; 45: 41-49, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36696791

RESUMO

INTRODUCTIONS: Patient size is a limiting factor for transesophageal echocardiography (TEE) in small dogs. The objective of this study was to describe imaging capabilities of two probes for TEE in small dogs. ANIMALS, MATERIALS, AND METHODS: Prospective study in 10 client-owned dogs weighing <4 kg with congenital heart disease (CHD). Dogs had TEE performed with a microprobe (10T-D, GE Medical) and intracardiac echocardiography (ICE) catheter-based probe (AcuNav™, Biosense Webster) in the esophagus in alternating order. Ease of placement, ability to acquire images of the CHD, image quality, and probe limitations were recorded. RESULTS: Median weight was 2.4 kg (range, 1.0-3.2). Congenital abnormalities included patent ductus arteriosus (n = 9) and pulmonary valve stenosis (n = 1). The 10T-D microprobe was easy to place (n = 8) or achievable with gentle manipulation (n = 2), and image quality of the CHD was optimal (n = 8), adequate (n = 1), or poor (n = 1). The ICE probe was difficult to place in the esophagus even with an external support system (n = 9) or could not be placed (n = 1), and image quality of the CHD was optimal (n = 2), adequate (n = 3), or poor (n = 5). Both probes provided images in a 1.0-kg dog. Probe limitations included lack of lateral motion (microprobe), the need for an external support system (ICE probe) and inability to consistently maintain contact with the esophagus (ICE probe). CONCLUSION: The 10T-D microprobe provided high-quality TEE images more consistently than the ICE probe in the majority of dogs in this study; however, the lack of lateral motion can diminish its utility in some dogs.


Assuntos
Doenças do Cão , Permeabilidade do Canal Arterial , Cães , Animais , Ecocardiografia Transesofagiana/veterinária , Ecocardiografia Transesofagiana/métodos , Estudos Prospectivos , Doenças do Cão/diagnóstico por imagem , Permeabilidade do Canal Arterial/diagnóstico por imagem , Permeabilidade do Canal Arterial/veterinária , Cateterismo Cardíaco/veterinária
8.
J Prev Alzheimers Dis ; 9(4): 625-634, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36281666

RESUMO

BACKGROUND: The onset of mild cognitive impairment (MCI) is an essential outcome in Alzheimer's disease (AD) prevention trials and a compelling milestone for clinically meaningful change. Determining MCI, however, may be variable and subject to disagreement. Adjudication procedures may improve the reliability of these determinations. We report the performance of an adjudication committee for an AD prevention trial. METHODS: The TOMMORROW prevention trial selected cognitively normal participants at increased genetic risk for AD and randomized them to low-dose pioglitazone or placebo treatment. When adjudication criteria were triggered, a participant's clinical information was randomly assigned to a three-member panel of a six-member independent adjudication committee. Determination of whether or not a participant reached MCI due to AD or AD dementia proceeded through up to three review stages - independent review, collaborative review, and full committee review - requiring a unanimous decision and ratification by the chair. RESULTS: Of 3494 participants randomized, the committee adjudicated on 648 cases from 386 participants, resulting in 96 primary endpoint events. Most participants had cases that were adjudicated once (n = 235, 60.9%); the rest had cases that were adjudicated multiple times. Cases were evenly distributed among the eight possible three-member panels. Most adjudicated cases (485/648, 74.8%) were decided within the independent review (stage 1); 14.0% required broader collaborative review (stage 2), and 11.1% needed full committee discussion (stage 3). The primary endpoint event decision rate was 39/485 (8.0%) for stage 1, 29/91 (31.9%) for stage 2, and 28/72 (38.9%) for stage 3. Agreement between the primary event outcomes supported by investigators' clinical diagnoses and the decisions of the adjudication committee increased from 50% to approximately 93% (after around 100 cases) before settling at 80-90% for the remainder of the study. CONCLUSIONS: The adjudication process was designed to provide independent, consistent determinations of the trial endpoints. These outcomes demonstrated the extent of uncertainty among trial investigators and agreement between adjudicators when the transition to MCI due to AD was prospectively assessed. These methods may inform clinical endpoint determination in future AD secondary prevention studies. Reliable, accurate assessment of clinical events is critical for prevention trials and may mean the difference between success and failure.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/prevenção & controle , Disfunção Cognitiva/complicações , Disfunção Cognitiva/tratamento farmacológico , Pioglitazona/uso terapêutico , Reprodutibilidade dos Testes , Projetos de Pesquisa
9.
J Vet Cardiol ; 43: 81-92, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36099705

RESUMO

INTRODUCTION/OBJECTIVES: Cavalier King Charles spaniels (CKCS) are ideal candidates for longitudinal study of myxomatous mitral valve (MV) disease and stage B1 clinical trials; however, the optimization of MV measurement acquisition and repeatability must be better defined to realize this potential. Additionally, breed-specific reference ranges for CKCS MV measurements are lacking. Study objectives were to assess measurement repeatability and define optimal methods for the longitudinal study of echocardiographic MV anatomy and to define preliminary, two-dimensional echocardiographic reference ranges for MV measurements in CKCS. ANIMALS: Forty CKCS between 10 and 24 months old. MATERIALS AND METHODS: Pre- and post-sedation two-dimensional echocardiographic images optimized for the MV were obtained. The length, width, and area of the anterior and posterior leaflets and the diameter of the MV annulus at end-diastole and end-systole were measured. Measurement repeatability was assessed using % coefficient of variation and repeatability coefficients. RESULTS: Intraoperator repeatability was best for the operator with previous MV measurement experience, with comparable results for the experienced operator measuring the second operator's images, mimicking a core echocardiography laboratory setting. Except for MV annulus diameter at end-systole, sedation had no significant effect on any MV measurements, nor did it impact measurement repeatability. Preliminary, breed-specific reference ranges were defined for the population, with CKCS often noted to have a larger annular diameter at end-systole than end-diastole. CONCLUSIONS: Optimal methods for longitudinal study of the MV in CKCS have been proposed, as have two-dimensional preliminary echocardiographic reference ranges for CKCS MV measurements. The MV annulus in CKCS may differ from other breeds.


Assuntos
Doenças do Cão , Doenças das Valvas Cardíacas , Cães , Animais , Valva Mitral/diagnóstico por imagem , Valores de Referência , Estudos Longitudinais , Ecocardiografia/veterinária , Doenças das Valvas Cardíacas/veterinária
10.
J Vet Cardiol ; 42: 83-91, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35863126

RESUMO

Four adult dogs weighing <10 kg presented for the evaluation of severe mitral valve stenosis with clinical signs. Owing to the size of the dogs, a hybrid surgical and interventional approach was utilized for balloon valvuloplasty. A left lateral thoracotomy was performed to allow direct entry through the left atrial wall. Transesophageal echocardiography was utilized for the entirety of the procedure in all dogs, and fluoroscopy was additionally used in two dogs. One dog had mild to moderate intra-operative bleeding from the left atrial wall during the procedure, but no other intra-operative complications were observed. No dogs developed a clinically relevant amount of worsened mitral regurgitation. Based on mitral leaflet mobility and transmitral flow profiles, there was perceived improvement in all four dogs. One dog died 6 h after extubation due to respiratory arrest. The remaining dogs survived to discharge and had resolution of clinical signs at home and discontinuation of heart failure medications. One dog died of an unknown cause at five months and another developed atrial fibrillation, and the owners elected to euthanize at ten months after the procedure. One dog continues to do well six months after the procedure as of the time of this writing. Hybrid balloon valvuloplasty can be a viable management option for small breed dogs with severe mitral stenosis exhibiting clinical signs, and both transesophageal echocardiography and fluoroscopy can be used intra-operatively to assist in successful procedural outcomes.


Assuntos
Fibrilação Atrial , Valvuloplastia com Balão , Estenose da Valva Mitral , Animais , Fibrilação Atrial/complicações , Fibrilação Atrial/veterinária , Valvuloplastia com Balão/veterinária , Ecocardiografia Transesofagiana/veterinária , Átrios do Coração/diagnóstico por imagem , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/cirurgia , Estenose da Valva Mitral/veterinária
11.
J Vet Cardiol ; 42: 15-22, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35662025

RESUMO

INTRODUCTION/OBJECTIVES: Intracardiac echocardiography (ICE) is a method of obtaining echocardiographic images with a steerable ultrasound catheter placed within the heart via a venous or arterial approach. The objectives of this study were to assess the feasibility of a 5-10 MHz, 8 French, 90 cm ICE catheter to evaluate cardiac structures and function in standing, sedated horses, and describe standard views in this species. ANIMALS: Ten apparently healthy horses weighing 458.1-618.2 kg from a university teaching herd. MATERIALS AND METHODS: Each horse had a physical examination, transthoracic echocardiography, and ICE performed through a 10 French introducer percutaneously placed in the right jugular vein in the proximal third of the neck with continuous ECG monitoring using telemetry. RESULTS: Three intracardiac echocardiography positions (cranial right atrium, mid right atrium, and right ventricle) with seven views were described with the associated 2D, pulse wave Doppler, continuous wave Doppler, color Doppler, and M-mode image acquisition standardized by referencing the intracardiac positions and common landmarks. The positions were confirmed with simultaneous transthoracic echocardiography. The procedure was well tolerated with only mild, occasional ventricular, and supraventricular arrhythmias that resolved with intracardiac echocardiography catheter repositioning. CONCLUSIONS: Intracardiac echocardiography is feasible, safe, and allows for the acquisition of diagnostic images in conscious, sedated horses.


Assuntos
Ecocardiografia , Ventrículos do Coração , Animais , Ecocardiografia/métodos , Ecocardiografia/veterinária , Estudos de Viabilidade , Átrios do Coração , Ventrículos do Coração/diagnóstico por imagem , Cavalos , Humanos , Pericárdio
12.
J Vet Cardiol ; 41: 44-56, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35240454

RESUMO

INTRODUCTION/OBJECTIVES: Minimal information exists regarding epicardial pacemaker (EP) implantation in pet ferrets (Mustela putorius furo). The objectives were to describe the indications, surgical technique, and outcome of EP implantation in ferrets for the treatment of advanced atrioventricular block (AVB). ANIMALS, MATERIALS, AND METHODS: Eight client-owned ferrets presenting to five veterinary referral centers. Signalment, physical exam findings, diagnostic tests, anesthesia protocols, surgical implantation techniques, postoperative treatment plans, and EP interrogations were reviewed. Intra- and postoperative, minor and major, and EP-related complications were established. Descriptive statistics were performed to report complication rates. Survival analyses were performed. RESULTS: All ferrets had advanced AVB: 3/8 had high-grade second-degree and 5/8 had third-degree. The primary clinical signs were collapse and weakness. Seven EP were implanted via a transdiaphragmatic approach and one via a left intercostal thoracotomy. Intraoperative complications occurred in 2/8 ferrets, both major. One ferret with severe comorbidities died during general anesthesia. Postoperative pacemaker-related complications were minor: inappropriate sinus beat sensing in 2/8 and occasional muscle fasciculations in 1/8. Two ferrets were alive at the time of manuscript submission, at 10 and 21 months postoperatively. The overall median survival time was 24 months. CONCLUSIONS: Implantation of EP was performed successfully in most ferrets for treatment of advanced AVB and was well tolerated. Ferrets with advanced AVB may experience resolution of clinical signs associated with their cardiac disease following EP implantation. Additional studies are warranted to investigate the effects of epicardial pacing on survival times in this species.


Assuntos
Bloqueio Atrioventricular , Cardiopatias , Marca-Passo Artificial , Animais , Bloqueio Atrioventricular/terapia , Bloqueio Atrioventricular/veterinária , Furões , Cardiopatias/veterinária , Marca-Passo Artificial/efeitos adversos , Marca-Passo Artificial/veterinária , Toracotomia/veterinária
13.
J Vet Cardiol ; 39: 69-78, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34996021

RESUMO

INTRODUCTION: Objectives: Patent ductus arteriosus (PDA) in dogs is often treated via minimally invasive transvascular occlusion using femoral artery access. This study compared ultrasound-derived diameter and image quality of the right femoral artery (RFA) and vein (RFV) in dogs with PDA using a linear ultrasound probe (L-P) and phased-array transthoracic echocardiography probe (TTE-P). The case outcome was assessed. ANIMALS, MATERIALS & METHODS: Forty-five client-owned dogs with PDA were prospectively enrolled. Ultrasound-measured RFA and RFV diameters were obtained on images acquired with both probes pre-operatively and compared using Bland-Altman plots. The image quality of RFA and RFV was scored on L-P and TTE-P images. RESULTS: Comparison of RFA and RFV diameter from L-P versus TTE-P images revealed: [Mean difference (limits of agreement): RFA = 0.009 mm (-0.78-0.79 mm), RFV = 0.523 mm (-1.75-2.79 mm)]. Image quality scores were significantly higher for L-P than TTE-P (P < 0.0001). In six small dogs, measurable images were unattainable with TTE-P. Dogs of similar body weight had variable RFA diameters. Twenty-seven dogs had RFA catheterization. In 21/27 dogs, RFA diameter exceeded the external diameter of the introducer used for catheterization, and in 6/27, it was smaller. CONCLUSIONS: Pre-procedural ultrasound of the RFA in dogs with PDA is useful given variable RFA diameter relative to body weight. Despite poorer image quality, RFA diameters from TTE-P images were very similar to L-P images on average, suggesting TTE-Ps are suitable for pre-procedural planning in most dogs. Vasospasm, hypotension or differences in the location of ultrasound measurement versus catheterization might produce variation in pre-procedural versus intraoperative RFA size.


Assuntos
Doenças do Cão , Permeabilidade do Canal Arterial , Animais , Cateterismo Cardíaco/veterinária , Cães , Permeabilidade do Canal Arterial/diagnóstico por imagem , Permeabilidade do Canal Arterial/cirurgia , Permeabilidade do Canal Arterial/veterinária , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Resultado do Tratamento , Ultrassonografia
14.
J Vet Cardiol ; 40: 126-141, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34483077

RESUMO

INTRODUCTION: Large breed (LB) dogs develop dilated cardiomyopathy (DCM) and myxomatous mitral valve disease (MMVD). Echocardiography is required for a definitive diagnosis but is not always available. Our objective was to assess the clinical utility of thoracic radiographs alone and in combination with physical examination and electrocardiography findings for the prediction of clinically important DCM or MMVD in LB dogs. ANIMALS: Four hundred fifty-five client-owned dogs ≥20 kg with concurrent thoracic radiographs and echocardiogram. MATERIALS AND METHODS: Medical records were reviewed and stored thoracic radiographs and echocardiographic images were measured to classify dogs as normal heart size (NHS), preclinical DCM, clinical DCM, preclinical MMVD (with cardiomegaly), clinical MMVD, or equivocal. Dogs with preclinical MMVD, without cardiomegaly, were classified as NHS. Vertebral heart size (VHS) and vertebral left atrial size (VLAS) were measured. Receiver operating characteristic curves and prediction models were derived. RESULTS: Prevalence of MMVD (39.3%) was higher than the prevalence of DCM (24.8%), though most MMVD dogs (67.0%) lacked cardiomegaly and were classified as NHS for analysis. The area under the curve for VHS to discriminate between NHS and clinical DCM/MMVD or preclinical DCM/MMVD was 0.861 and 0.712, respectively, while for VLAS, it was 0.891 and 0.722, respectively. Predictive models incorporating physical examination and electrocardiography findings in addition to VHS/VLAS increased area under the curve to 0.978 (NHS vs. clinical DCM/MMVD) and 0.829 (NHS vs. preclinical DCM/MMVD). CONCLUSIONS: Thoracic radiographs were useful for predicting clinically important DCM or MMVD in LB dogs, with improved discriminatory ability when physical examination abnormalities and arrhythmias were accounted for.


Assuntos
Cardiomiopatia Dilatada , Doenças do Cão , Doenças das Valvas Cardíacas , Animais , Cardiomegalia/veterinária , Cardiomiopatia Dilatada/veterinária , Doenças do Cão/diagnóstico por imagem , Cães , Ecocardiografia/veterinária , Eletrocardiografia/veterinária , Doenças das Valvas Cardíacas/veterinária , Valva Mitral/diagnóstico por imagem
15.
Phys Rev Lett ; 127(16): 162501, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34723594

RESUMO

We report an improved measurement of the free neutron lifetime τ_{n} using the UCNτ apparatus at the Los Alamos Neutron Science Center. We count a total of approximately 38×10^{6} surviving ultracold neutrons (UCNs) after storing in UCNτ's magnetogravitational trap over two data acquisition campaigns in 2017 and 2018. We extract τ_{n} from three blinded, independent analyses by both pairing long and short storage time runs to find a set of replicate τ_{n} measurements and by performing a global likelihood fit to all data while self-consistently incorporating the ß-decay lifetime. Both techniques achieve consistent results and find a value τ_{n}=877.75±0.28_{stat}+0.22/-0.16_{syst} s. With this sensitivity, neutron lifetime experiments now directly address the impact of recent refinements in our understanding of the standard model for neutron decay.

16.
Phys Rev Lett ; 127(15): 155002, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34678005

RESUMO

The study of high-velocity particle-laden flow interactions is of importance for the understanding of a wide range of natural phenomena, ranging from planetary formation to cloud interactions. Experimental observations of particle dynamics are sparse given the difficulty of generating high-velocity flows of many particles. Ejecta microjets are micron-scale jets formed by strong shocks interacting with imprinted surfaces to generate particle plumes traveling at several kilometers per second. As such, the interaction of two ejecta microjets provides a novel experimental methodology to study interacting particle streams. In this Letter, we report the first time sequences of x-ray radiography images of two interacting tin ejecta microjets taken on a platform designed for the OMEGA Extended Performance (OMEGA EP) laser. We observe that the microjets pass through each other unattenuated for the case of 11.7±3.2 GPa shock pressures and jet velocities of 2.2±0.5 km/s but show strong interaction dynamics for 116.0±6.1 GPa shock pressures and jet velocities of 6.5±0.5 km/s. We find that radiation-hydrodynamic simulations of the experiments are able to capture many aspects of the collisional behavior, such as the attenuation of jet velocity in the direction of propagation, but are unable to match the full spread of the strongly interacting cloud.

17.
AJNR Am J Neuroradiol ; 42(11): 1942-1948, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34620589

RESUMO

BACKGROUND AND PURPOSE: Many patients with dementia may have comorbid or misdiagnosed normal pressure hydrocephalus, a treatable neurologic disorder. The callosal angle is a validated biomarker for normal pressure hydrocephalus with 93% diagnostic accuracy. Our purpose was to develop and evaluate an algorithm for automatically computing callosal angles from MR images of the brain. MATERIALS AND METHODS: This article reports the results of analyzing callosal angles from 1856 subjects with 5264 MR images from the Open Access Series of Imaging Studies and the Alzheimer's Disease Neuroimaging Initiative databases. Measurement variability was examined between 2 neuroradiologists (n = 50) and between manual and automatic measurements (n = 281); from differences in simulated head orientation; and from real-world changes in patients with multiple examinations (n = 906). We evaluated the effectiveness of the automatic callosal angle to differentiate normal pressure hydrocephalus from Alzheimer disease in a simulated cohort. RESULTS: The algorithm identified that 12.4% of subjects from these carefully screened cohorts had callosal angles of <90°, a published threshold for possible normal pressure hydrocephalus. The intraclass correlation coefficient was 0.97 for agreement between neuroradiologists and 0.90 for agreement between manual and automatic measurement. The method was robust to different head orientations. The median coefficient of variation for repeat examinations was 4.2% (Q1 = 3.1%, Q3 = 5.8%). The simulated classification of normal pressure hydrocephalus versus Alzheimer using the automatic callosal angle had an accuracy, sensitivity, and specificity of 0.87 each. CONCLUSIONS: In even the most pristine research databases, analyses of the callosal angle indicate that some patients may have normal pressure hydrocephalus. The automatic callosal angle measurement can rapidly and objectively screen for normal pressure hydrocephalus in patients who would otherwise be misdiagnosed.


Assuntos
Hidrocefalia de Pressão Normal , Idoso , Corpo Caloso/diagnóstico por imagem , Humanos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neuroimagem , Voluntários
18.
J Small Anim Pract ; 62(8): 613-623, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34180062

RESUMO

Congenital heart disease is an important subset of all cardiovascular disease in dogs and cats that is present at birth and most often detected in young animals but can be diagnosed in adulthood. The range of abnormalities that can occur during development of the heart is vast incorporating simple and complex defects, varying degrees of severity and clinical presentations that include heart failure and cyanosis. While some defects do not result in morbidity in an individual animal, others cause severe clinical signs and death at a young age. Advances in imaging and expanding treatment options offer increasingly more possibilities in the diagnosis and management of congenital heart disease which is the focus of this review. The objective is to provide a broad overview of current practice and highlight key aspects to guide practitioners in their approach to congenital heart disease diagnosis and knowledge of available treatment options.


Assuntos
Doenças do Gato , Doenças do Cão , Cardiopatias Congênitas , Insuficiência Cardíaca , Animais , Doenças do Gato/diagnóstico , Doenças do Gato/terapia , Gatos , Cianose/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/terapia , Cães , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/terapia , Cardiopatias Congênitas/veterinária , Insuficiência Cardíaca/veterinária
19.
Sci Rep ; 11(1): 12883, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145307

RESUMO

We present structure and equation of state (EOS) measurements of biaxially orientated polyethylene terephthalate (PET, [Formula: see text], also called mylar) shock-compressed to ([Formula: see text]) GPa and ([Formula: see text]) K using in situ X-ray diffraction, Doppler velocimetry, and optical pyrometry. Comparing to density functional theory molecular dynamics (DFT-MD) simulations, we find a highly correlated liquid at conditions differing from predictions by some equations of state tables, which underlines the influence of complex chemical interactions in this regime. EOS calculations from ab initio DFT-MD simulations and shock Hugoniot measurements of density, pressure and temperature confirm the discrepancy to these tables and present an experimentally benchmarked correction to the description of PET as an exemplary material to represent the mixture of light elements at planetary interior conditions.

20.
Rev Sci Instrum ; 92(2): 023305, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648127

RESUMO

In this paper, we report studies of the Fermi potential and loss per bounce of ultracold neutrons (UCNs) on a deuterated scintillator (Eljen-299-02D). These UCN properties of the scintillator enable its use in a wide variety of applications in fundamental neutron research.

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