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1.
Adv Exp Med Biol ; 1232: 55-62, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893394

RESUMO

The aim was to investigate the feasibility of simultaneous comparison of cerebral circulation in major vessels and microvasculature in patients suffering traumatic brain injury (TBI) with or without intracranial hematomas (IH). METHODS: 170 patients were divided into two groups: Group 1 - diffuse TBI (75 patients); and Group 2 - TBI with IH (95 patients: 18 epidural, 65 subdural and 12 multiple). Perfusion computed tomography (PCT) for assessment of volumetric cerebral blood flow (CBF) was done 2-15 days after admission to hospital. Simultaneous assessment of cerebral blood flow velocity (CBFV) in both middle cerebral arteries was done by transcranial Doppler. RESULTS: In patients with diffuse TBI, CBF had statistically valid correlations with CBFV (r = 0.28, p = 0.0149 on the left side; r = 0.382, p = 0.00075 on the right side). In patients with TBI and IH, the analysis did not reveal any reliable correlations between the CBFV and CBF velocity in the temporal lobes, either on the side of the removed IH or on the opposite side. CONCLUSION: The greatest linear correlation was noted in patients with diffuse TBI without the development of a coarse shift of the midline structures and dislocation syndrome. This correlation decreases with the increase in injury severity and development of secondary complications in the acute period, which probably reflects impairment of the coupling of oxygen consumption by brain tissue and cerebral microcirculation.


Assuntos
Lesões Encefálicas Traumáticas , Circulação Cerebrovascular , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler Transcraniana , Velocidade do Fluxo Sanguíneo , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Humanos , Artéria Cerebral Média/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas , Ultrassonografia Doppler Transcraniana/normas
2.
Adv Exp Med Biol ; 1232: 69-75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893396

RESUMO

We investigated the relationship between cerebral oxygenation (COX) and skin blood flow (SkBF) at the left frontal lobes of 10 healthy young men during progressive hypoxia (∼ -1 h at each of 21%, 18%, 15%, and 12% of inspired oxygen [FiO2]). Acute hypotension was manipulated by a thigh-cuff-release technique, where a pressure of 220 mmHg was applied at both thigh muscles for 3 min and the cuff was immediately released to induce acute hypotension. While the resting baseline for COX before the thigh-cuff release manipulation decreased gradually with the reduction of FiO2 (P < 0.05), the resting baseline for SkBF, mean arterial blood pressure (MAP), and cutaneous vascular conductance (CVC) were unaffected by FiO2 (P > 0.05). The acute hypotension that was induced by the thigh-cuff release decreased COX, SkBF, MAP, and CVC; thereafter, these values recovered toward their baseline values. During the hypotension phase, while the time to the nadir values for COX slowed progressively with reductions in FiO2 (P < 0.05), those for SkBF, MAP, and CVC were unaffected by FiO2 (P > 0.05). These results suggest that COX may not be associated with SkBF for the protocol or with the subjects in the present study.


Assuntos
Circulação Cerebrovascular , Lobo Frontal , Hipotensão , Pele , Adulto , Velocidade do Fluxo Sanguíneo , Lobo Frontal/fisiologia , Hemodinâmica , Humanos , Hipotensão/fisiopatologia , Masculino , Pele/irrigação sanguínea , Adulto Jovem
3.
Arch Dis Child Fetal Neonatal Ed ; 105(1): 26-32, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31092674

RESUMO

INTRODUCTION: During delayed umbilical cord clamping, the factors underpinning placental transfusion remain unknown. We hypothesised that reductions in thoracic pressure during inspiration would enhance placental transfusion in spontaneously breathing preterm lambs. OBJECTIVE: Investigate the effect of spontaneous breathing on umbilical venous flow and body weight in preterm lambs. METHODS: Pregnant sheep were instrumented at 132-133 days gestational age to measure fetal common umbilical venous, pulmonary and cerebral blood flows as well as arterial and intrapleural (IP) pressures. At delivery, doxapram and caffeine were administered to promote breathing. Lamb body weights were measured continuously and breathing was assessed by IP pressure changes. RESULTS: In 6 lambs, 491 out of 1117 breaths were analysed for change in body weight. Weight increased in 46.6% and decreased in 47.5% of breaths. An overall mean increase of 0.02±2.5 g per breath was calculated, and no net placental transfusion was observed prior to cord clamping (median difference in body weight 52.3 [-54.9-166.1] g, p=0.418). Umbilical venous (UV) flow transiently decreased with each inspiration, and in some cases ceased, before UV flow normalised during expiration. The reduction in UV flow was positively correlated with the standardised reduction in (IP) pressure, increasing by 109 mL/min for every SD reduction in IP pressure. Thus, the reduction in UV flow was closely related to inspiratory depth. CONCLUSIONS: Spontaneous breathing had no net effect on body weight in preterm lambs at birth. UV blood flow decreased as inspiratory effort increased, possibly due to constriction of the inferior vena cava caused by diaphragmatic contraction, as previously observed in human fetuses.


Assuntos
Circulação Placentária/fisiologia , Respiração , Cordão Umbilical , Veias Umbilicais/fisiologia , Animais , Animais Recém-Nascidos , Velocidade do Fluxo Sanguíneo/fisiologia , Peso Corporal , Constrição , Modelos Animais de Doenças , Feminino , Gravidez , Nascimento Prematuro , Ovinos , Fatores de Tempo
4.
Vasc Endovascular Surg ; 54(1): 5-11, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31506033

RESUMO

INTRODUCTION: High flow rates may develop in arteriovenous fistula (AVF), resulting in clinical syndromes of steal, aneurysmal fistula, or high-output cardiac failure. Various techniques with varying success have been advocated to treat this difficult problem. We present a hemodynamically validated novel banding technique. METHODS: We designed a computational fluid dynamic (CFD) model of the native high-flow AVF and tested various juxta-anastomotic venous diameters to determine the effect on AVF blood flow and pressure. We translated this principle in our banding technique, wherein adjustable banding was performed in conjunction with ultrasound-guided brachial artery flow measurement to determine the optimal band diameter. Polyurethane patch was used to fashion the adjustable band. Patient demographics, AVF flow parameters pre- and postintervention, operative intervention, and ultrasound follow-up data were collected prospectively. RESULTS: Our CFD testing demonstrated that the band diameter needed to achieve optimal distal blood pressure and preserve AVF flow depending on blood pressure, end capillary pressure, venous pressure, and vascular diameters. Five patients subsequently underwent dynamic banding of symptomatic high-flow AVF. Mean brachial artery blood flow rates pre- and postbanding were 2964 mL/min (confidence interval [CI]: 1487-4440 mL/min) and 1099 mL/min (CI: 571.7-1627 mL/min), respectively (P = .01). All patients had symptomatic improvement, and at a mean follow-up of 1 year, this benefit was sustained with no AVF thrombosis or loss. CONCLUSION: Adjustable dynamic band using ultrasound-guided brachial artery flow shows promising results in producing accurate AVF blood flow reduction with sustained efficacy in the short term for patients with symptomatic high-flow AVF.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Artéria Braquial/fisiopatologia , Hemodinâmica , Complicações Pós-Operatórias/cirurgia , Diálise Renal , Adolescente , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Artéria Braquial/diagnóstico por imagem , Simulação por Computador , Humanos , Ligadura , Pessoa de Meia-Idade , Modelos Cardiovasculares , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Fluxo Sanguíneo Regional , Reoperação , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção
5.
Medicine (Baltimore) ; 98(50): e18234, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852087

RESUMO

The aim of this prospective observational single-centre pilot study was to evaluate the association between alterations in carotid artery blood flow velocities during cardiac surgery and postoperative delirium.Carotid artery blood flow velocity was determined perioperatively at 5 different timepoints by duplex sonography in 36 adult cardiac surgical patients. Delirium was assessed using the Confusion Assessment Method for the ICU and the Intensive Care Delirium Screening Checklist. Additionally, blood flow velocities in the middle cerebral arteries, differences in regional cerebral tissue oxygenation and quantity and quality of microemboli were measured.Delirium was detected in 7 of 36 patients. After cardiopulmonary bypass carotid artery blood flow velocities increased by +23 cm/second (95% confidence interval (CI) 9-36 cm/second) in non-delirious patients compared to preoperative values (P = .002), but not in delirious patients (+3 cm/second [95% CI -25 to 32 cm/second], P = .5781). Middle cerebral artery blood flow velocities were higher at aortic de-cannulation in non-delirious patients (29 cm/second [inter-quartile range (IQR), 24-36 cm/second] vs 12 cm/second [IQR, 10-19 cm/second]; P = .017). Furthermore, brain tissue oxygenation was higher in non-delirious patients during surgery.Our results suggest that higher cerebral blood flow velocities after aortic de-clamping and probably also improved brain oxygenation might be beneficial to prevent postoperative delirium.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Artéria Carótida Primitiva/fisiopatologia , Delírio/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Ultrassonografia Doppler Dupla/métodos , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Artéria Carótida Primitiva/diagnóstico por imagem , Delírio/etiologia , Delírio/fisiopatologia , Feminino , Seguimentos , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Valor Preditivo dos Testes , Estudos Prospectivos
6.
Zhonghua Nei Ke Za Zhi ; 58(11): 814-818, 2019 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-31665856

RESUMO

Objective: To investigate the clinical significance of transcranial Doppler (TCD) in early diagnosis of sepsis-associated encephalopathy(SAE). Methods: Septic patients admitted to the intensive care unit(ICU) were recruited at Xiangya Hospital, Central South University from July 2015 to March 2016. Clinical data and TCD parameters during 24 hours after admission were collected. All patients were screened for delirium using the confusion assessment method for the intensive care unit (CAM-ICU) twice a day. The gold standard of the diagnosis of SAE was positive CAM-ICU evaluation. Patients were divided into SAE group and the non-SAE group. TCD data including systolic velocity (Vs), diastolic velocity (Vd), mean velocity (Vm), pulsatility index (PI) and resistant index (RI) were analyzed to determine the optimal diagnostic cut-off value. Results: A total of 43 patients were enrolled including 12 in SAE group and 31 in non-SAE group. Vm and Vd were lower in SAE group [Vm: (53.50±12.22) cm/s vs. (61.68±9.63) cm/s, P<0.05; Vd: (33.42±10.87) cm/s vs. (43.16±7.84) cm/s, P<0.01] but PI and RI were significant higher in SAE group[PI:(1.16±0.2) vs. (0.90±0.15), P<0.01;RI:(0.65±0.08) vs. (0.56±0.06), P<0.01] than in non-SAE group. The cut-off values of Vs, Vm, Vd, PI and RI for the diagnosis of SAE were 112cm/s, 55.50cm/s, 34.50cm/s, 1.16, 0.65, respectively, with the relevant sensitivities of 19.4%, 83.9%, 93.5%, 58.3%, 58.3% and the specificities of 100.0%, 50.0%, 58.3%, 96.8%, 96.8%, respectively. The diagnostic AUC of Vd, PI and RI were 0.741, 0.808 and 0.808 respectively. Conclusions: The parameter changes of TCD suggest that the pathogenesis of SAE is related to cerebral hypoperfusion, TCD is a helpful method for the early diagnosis of SAE.


Assuntos
Circulação Cerebrovascular , Artéria Cerebral Média/diagnóstico por imagem , Encefalopatia Associada a Sepse/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Diagnóstico Precoce , Humanos , Unidades de Terapia Intensiva
7.
J Vasc Res ; 56(6): 296-307, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31671424

RESUMO

In this study, using fluid-structure interaction (FSI), 3-dimensional blood flow in an aneurysm in the circle of Willis - which is located in the middle cerebral artery (MCA) - has been simulated. The purpose of this study is to evaluate the effect of a partly blocked vessel on an aneurysm. To achieve this purpose, two cases have been investigated using the FSI method: in the first case, an ideal geometry of aneurysm in the MCA has been simulated; in the second case, modeling is performed for an ideal geometry of the aneurysm in the MCA with a partly blocked vessel. All boundary conditions, properties and modeling methods were considered the same for both cases. The only difference between the two cases was that part of the MCA parent artery was blocked in the second case. In order to consider the hyperelastic property of the wall and the non-Newtonian properties of the blood, the Mooney-Rivlin model and the Carreau model have been used, respectively. In the second case, the Von Mises stress in the peak systole is 26% higher than in the first case. With regard to the high amount of Von Mises stress, the risk of rupture of the aneurysm is higher in this case. In the second case, the maximum wall shear stress (WSS) is 12% higher than in the first case. And maximum displacement in the second case is also higher than in the first. So, the risk of growth of the aneurysm is higher in cases with a partly blocked vessel.


Assuntos
Circulação Cerebrovascular , Círculo Arterial do Cérebro/fisiopatologia , Simulação por Computador , Infarto da Artéria Cerebral Média/fisiopatologia , Aneurisma Intracraniano/fisiopatologia , Modelos Cardiovasculares , Idoso , Velocidade do Fluxo Sanguíneo , Angiografia Cerebral/métodos , Círculo Arterial do Cérebro/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Progressão da Doença , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Fluxo Sanguíneo Regional
8.
Vasc Health Risk Manag ; 15: 375-384, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695398

RESUMO

Background: Survivors of myocardial infarction (MI) are at high risk of new major adverse cardiovascular events (MACE). Coronary flow reserve (CFR) is a strong and independent predictor of MACE. Understanding the prevalence of impaired CFR in this patient group and identifying risk markers for impaired CFR are important steps in the development of personalized and targeted treatment for high-risk individuals with prior MI. Methods: PROFLOW is a prospective, exploratory, cross-sectional open study. We used information from the SCAAR (Swedish Coronary Angiography and Angioplasty Registry) to identify high-risk patients with a history of type-1 MI. We measured CFR non-invasively in a left anterior descending artery (LAD) using transthoracic Doppler echocardiography. Coronary flow velocity was measured at rest and at maximal flow after induction of hyperemia by intravenous infusion of adenosine (140 µg/kg/min). Independent predictors of CFR were assessed with multiple linear regression. Results: We included 619 patients. The median age was 69 (IQR 65-73), and 114 (18.4%) were women. Almost one-half of the patients, 285 (46.0%) had the multi-vessel disease, and 147 (23.7%) were incompletely revascularized. The majority were on optimal standard treatment eg ASA (93.1%), statins (90.0%), ACEI/ARB (82.6%) and beta-blockers (80.8%). The majority, 547 (88.4%) had no angina pectoris, and 572 (92.2%) were in NYHA class I. Evaluation of CFR was possible in 611 (98.7%) patients. Mean CFR was 2.74 (±0.79 (mean ± SD)). A substantial number of patients (39.7%) had CFR ≤2.5. In a multiple linear regression model age, dyslipidemia, smoking, hypertension, body mass index, incomplete revascularization, and treatment with angiotensin receptor blockers were independent predictors of CFR. Conclusion: In this high-risk group of patients with prior MI, the prevalence of impaired CFR was high. Further risk stratification with CFR in addition to traditional cardiovascular risk factors may improve predictive accuracy for future MACE in this patient population.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Ecocardiografia Doppler , Reserva Fracionada de Fluxo Miocárdico , Infarto do Miocárdio/diagnóstico por imagem , Adenosina/administração & dosagem , Idoso , Velocidade do Fluxo Sanguíneo , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/terapia , Vasos Coronários/fisiopatologia , Estudos Transversais , Feminino , Humanos , Hiperemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Prevenção Secundária , Suécia/epidemiologia , Vasodilatadores/administração & dosagem
9.
J Drugs Dermatol ; 18(11): 1180-1182, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31741363

RESUMO

Background: Significant advances have been made in using lasers and intense pulse light sources to treat common vascular lesions such as telangiectasias. However, the treatment of leg telangiectasia, specifically, is more challenging because it involves the clearing of smaller veins as well as the larger feeding veins. The latest guidelines recommend use of short wavelength pulse-dyed lasers (PDL) as an option to treat telangiectasia cases that are unresponsive to sclerotherapy. Methods: A 29-year-old white woman presented with persistent telangiectasia, with multiple telangiectasias ranging from 1 cm to 20 cm in size involving the dorsal feet and both ankles and legs, which developed 10 years prior, associated with paresthesia. Test spots were treated with a 585-nm pulsed dye laser with various energy settings, and treatment was performed at 5.5 J/cm2 with spot size 10 mm and 0.5ms pulse duration. Results: Near complete clearance was achieved 1 month after the single treatment without adverse effects. Optical coherence tomography (OCT) imaging demonstrated a reduction of cutaneous blood flow after treatment. Discussion: We report successful treatment despite using settings that were previously reported to lack efficacy. This treatment resulted in considerable improvement in aesthetics and symptomatology. Also, OCT confirmed decreased vascular flow and bulging. Conclusion: Our results suggest there is still much to learn about the use of PDL in treating telangiectasias of the lower extremities, and that the ideal parameters warrant further investigation. Moreover, the novel use of OCT in auxiliary imaging for identification of treatment spots, as well as monitoring response at a microvascular level, holds great potential for wider application. J Drugs Dermatol. 2019;18(11):1180-1182.


Assuntos
Lasers de Corante/uso terapêutico , Perna (Membro)/irrigação sanguínea , Terapia com Luz de Baixa Intensidade , Telangiectasia/radioterapia , Adulto , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Tomografia de Coerência Óptica
10.
J Cardiovasc Surg (Torino) ; 60(6): 742-748, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31599142

RESUMO

BACKGROUND: Our aim was to investigate the impact of the non-skeletonized (pedicled) versus the skeletonized left internal mammary (LIMA) harvesting technique on the postoperative sternal and parasternal skin perfusion in patients undergoing coronary artery bypass grafting (CABG), as compared to patients undergoing non-CABG heart surgery. METHODS: We included 142 patients who underwent non-bypass (N.=39) or CABG surgery (N.=103). CABG cases were differentiated according to the LIMA harvesting technique: skeletonized (N.=74) or non-skeletonized (N.=29). Parasternal and sternal skin perfusion measurements via a Laser Doppler Imaging tool were performed on the preoperative day and 5-7 days postoperatively, using a grid of 15 spatially segregated measurement points across the chest and normalization to a distinct reference point. Data were analyzed retrospectively. RESULTS: In the CABG group, the non-skeletonized LIMA harvesting resulted in a near-significant (P=0.057, two-sided Student t-test, 95% CI -[0.111, 0.002]), and the skeletonized LIMA harvesting in a significant (P< 0.001, 95% CI [-0.096, -0.032]) post-surgical decrease of left-sided parasternal skin perfusion in arbitrary perfusion units (APU), as compared to right-sided parasternal skin perfusion. No corresponding differences were found for the non-bypass group (P=0.5, 95% CI [-0.065, 0.033]). The harvesting techniques did not yield significantly different post-surgical parasternal skin perfusion measures in the CABG group (P=0.6). CONCLUSIONS: Measurement of parasternal skin perfusion using Laser Doppler Imaging is feasible. Both harvesting techniques resulted in a reduced parasternal/sternal skin perfusion upon removal of the internal mammary artery.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Fluxometria por Laser-Doppler , Artéria Torácica Interna/transplante , Imagem de Perfusão/métodos , Pele/irrigação sanguínea , Coleta de Tecidos e Órgãos/efeitos adversos , Idoso , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Fatores de Risco , Esterno , Resultado do Tratamento
11.
Zhonghua Yan Ke Za Zhi ; 55(10): 757-762, 2019 Oct 11.
Artigo em Chinês | MEDLINE | ID: mdl-31607064

RESUMO

Objective: To observe changes in foveal avascular zone(FAZ) and capillary plexus in idiopathic macular epiretinal membrane (IMEM) in optical coherence tomography angiography (OCTA) and analyze their correlation with the visual acuity. Methods: Cross-sectional study. 42 patients (15 Males and 27 females, age 64.8) from the Eye Hospital of Wenzhou Medical University were included with 51 eyes diagnosed as IMEM (IMEM group), and 23 normal eyes (9 Males and 14 females, control group). All patients received the examination of fissure lamp combined with fundus pre-set lens, best corrected visual acuity (BCVA), OCT angiography (OCTA) and fundus photo. OCTA was performed on 3 mm× 3 mm sections centred on the fovea. The software automatically measured the superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density(VD) and retinal thickness(RT) and FAZ area. The IMEM eyes were compared with the normal eyes and correlation between the parameters of OCTA and BCVA was analyzed in IMEM. Independent-sample t test and MannWhitney test were used for comparison between groups, and Spearman test was used for correlation analysis. Results: LogMAR BCVA in the IMEM group was 0.40(0.15, 0.70), in the control group was 0.10(0.05, 0.22). FAZ area of IMEM group was (0.09±0.05) mm(2), while that of control group was (0.34±0.13)mm(2).Compared with the control group, in IMEM group, the BCVA was worse (Z=-4.443, P<0.001), FAZ area was smaller (t=-9.198, P<0.001), RT was increased (P<0.001), The foveal DCP and SCP vessel density was increased (t=4.280, 9.079, P<0.01), The parafoveal DCP vessel density was decreased (P<0.05), The parafoveal SCP vessel density was decreased in superior, inferior and nasal side (t=-2.759, Z=-3.998, Z=-2.108; P<0.05). The BCVA was negatively correlated with FAZ area (r=-0.337, P=0.017), positively correlated with center macular thickness (r=0.324, P=0.020). The BCVA was no correlated with foveal VD and parafoveal DCP vessel density (P>0.05), but correlated with SCP vessel density(P<0.05). Conclusions: In the IMEM eyes the BCVA was worse, FAZ area was smaller, foveal vessel density was increased and the parafoveal vessel density was decreased compared with the normal eyes. The smaller the FAZ area, the smaller foveal SCP vessel density, the poorer BCVA. There was no correlation between BCVA and DCP vessel density. Changes in VD in IMEM eyes may lead to changes in vision. (Chin J Ophthalmol, 2019, 55:757-762).


Assuntos
Membrana Epirretiniana/diagnóstico por imagem , Angiofluoresceinografia/métodos , Fóvea Central/irrigação sanguínea , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Tomografia de Coerência Óptica , Angiografia , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Estudos Transversais , Feminino , Fóvea Central/diagnóstico por imagem , Humanos , Masculino , Acuidade Visual
14.
Praxis (Bern 1994) ; 108(12): 807-813, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31530132

RESUMO

Color Doppler ultrasound is the diagnostic cornerstone of vascular assessment. Almost all arteries and veins of the human body are accessible to this diagnostic imaging, which as a result is very often used as first-line diagnostic test. Recent technological developments in high-end ultrasound machines enable us to optimize image quality in color-coded duplex ultrasound of arteries and veins. To obtain an optimal instrument setting, all relevant adjustments of imaging must be considered. In B-Mode ultrasound, the basic vascular imaging method, the most important settings to optimize are ultrasound frequency, gain, dynamic range, and focus, whereas color Doppler depends on angle supersonic sounding and its application in clinical practice. Most mistakes in measuring blood flow velocities, a frequent cause of misinterpretation, result from insufficient angle correction. Cardiac pathologies may result in typical changes of arterial and venous Doppler curves.


Assuntos
Cardiopatias , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler Dupla , Artérias , Velocidade do Fluxo Sanguíneo , Cardiopatias/diagnóstico por imagem , Humanos , Ultrassonografia
15.
J Stroke Cerebrovasc Dis ; 28(11): 104374, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31530480

RESUMO

Traumatic cerebral aneurysms are histologically dissecting aneurysms or pseudoaneurysms, thus requiring parent artery occlusion for cure. Combination of endovascular parent artery occlusion and extracranial-intracranial bypass is considered optimal to obtain complete obliteration of the aneurysm and to avoid hemodynamic hypoperfusion. However, endovascular parent artery occlusion of the supraclinoid internal carotid artery (ICA) is at risk of ischemic complications due to distal coil protrusion to adjacent perforating arteries or distal embolism of the thrombi generated in the coil mass. A 20-year-old man presented with progressive left optic neuropathy following motor vehicle accident. Radiological examination revealed left supraclinoid ICA aneurysmal formation with dissecting change. We treated this traumatic supraclinoid ICA aneurysm by combination of endovascular parent artery occlusion and high-flow bypass in the hybrid operating room. An aneurysmal clip was applied on the ICA just distal to the aneurysm prior to coil embolization, and worked as a scaffold for subsequent filling coils and as a blockade for the distal emboli. This "clip anchor-assisted coil embolization" technique resulted in optimal parent artery occlusion for the traumatic aneurysm of the supraclinoid ICA with minimal risks of residual blood flow, intraoperative rupture, and thromboembolic complications.


Assuntos
Acidentes de Trânsito , Aneurisma Dissecante/terapia , Embolização Terapêutica/instrumentação , Procedimentos Endovasculares/instrumentação , Aneurisma Intracraniano/terapia , Artéria Radial/transplante , Enxerto Vascular , Aneurisma Dissecante/diagnóstico por imagem , Aneurisma Dissecante/fisiopatologia , Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Masculino , Resultado do Tratamento , Adulto Jovem
16.
Arch Endocrinol Metab ; 63(5): 495-500, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482952

RESUMO

OBJECTIVES: The differentiation between the various etiologies of thyrotoxicosis, including those with hyperthyroidism (especially Graves' disease [GD], the most common cause of hyperthyroidism) and without hyperthyroidism (like thyroiditis), is an important step in planning specific therapy. Technetium-99m (99mTc) pertechnetate thyroid scanning is the gold standard in differentiating GD from thyroiditis. However, this technique has limited availability, is contraindicated in pregnancy and lactation, and is not helpful in cases with history of recent exposure to excess iodine. The aim of this study was to identify the diagnostic value of the peak systolic velocity of the inferior thyroid artery (PSV-ITA) assessed by color-flow Doppler ultrasound (CFDU) and compare the sensitivity and specificity of this method versus 99mTc pertechnetate thyroid uptake. SUBJECTS AND METHODS: We prospectively analyzed 65 patients (46 with GD and 19 with thyroiditis). All patients were evaluated with clinical history and physical examination and underwent 99mTc pertechnetate scanning and measurement of TRAb levels and PSV-ITA values by CFDU. The diagnosis was based on findings from signs and symptoms, physical examination, and 99mTc pertechnetate uptake. RESULTS: Patients with GD had significantly higher mean PSV-ITA values than those with thyroiditis. At a mean PSV-ITA cutoff value of 30 cm/sec, PSV-ITA discriminated GD from thyroiditis with a sensitivity of 91% and specificity of 89%. CONCLUSION: Measurement of PSV-ITA by CFDU is a good diagnostic approach to discriminate between GD and thyroiditis, with sensitivity and specificity values comparable to those of 99mTc pertechnetate thyroid uptake.


Assuntos
Doença de Graves/diagnóstico por imagem , Glândula Tireoide/diagnóstico por imagem , Tireoidite/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Pertecnetato Tc 99m de Sódio , Glândula Tireoide/irrigação sanguínea
17.
Angiol Sosud Khir ; 25(3): 107-112, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31503254

RESUMO

Computer-aided simulation appropriately using the method of computational fluid dynamics (CFD) makes it possible to determine the elevated-risk zones of most probable formation of restenosis. The main idea of the method described in our article consists in a possibility of creating by the model of the geometrical shape of the vessel and characteristics of the flow at inlets and outlets the parameters of flow in each point of a vessel. The curves of velocity are used to create the curves of pressure at inlets and outlets, which are used in a CFD model. The resulting from CFD simulation of blood flow are nonstationary three-dimensional fields of pressure and velocity in the area under study. Visual examination of the dynamics of these fields makes it possible to judge about possible problem zones inside the area of flow and on the internal wall of the vessel. This article also presents a clinical case report illustrating the use of this technique.


Assuntos
Artérias Carótidas , Endarterectomia das Carótidas , Velocidade do Fluxo Sanguíneo , Artérias Carótidas/fisiopatologia , Hemodinâmica , Humanos , Modelos Cardiovasculares
18.
Med. clín (Ed. impr.) ; 153(6): 232-238, sept. 2019. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-184028

RESUMO

Introducción y objetivo: La hipertensión pulmonar asocia peor pronóstico en insuficiencia cardiaca (IC). En este estudio buscamos identificar predictores pronósticos no invasivos en IC con y sin hipertensión pulmonar asociada, mediante resonancia magnética cardiaca y determinación de marcadores de estrés oxidativo y antiinflamatorios. Pacientes y métodos: Inclusión prospectiva de 70 pacientes ingresados por IC de comienzo, en los que se determinó la velocidad media de arteria pulmonar (vmAP) y la concentración sanguínea de TroloxTM (estatus antioxidante) e IL-10 (citocina antiinflamatoria). La muestra se dividió en dos grupos de acuerdo con el valor óptimo de vmAP para la predicción de sucesos calculados mediante curva ROC (vmAP=8cm/s), considerando los reingresos por IC y la mortalidad global como el suceso cardiovascular primario. Resultados: Tras una mediana de seguimiento de 290 días se produjeron 16 episodios. La vmAP ≤8cm/s predijo una mayor incidencia de episodios en pacientes con función ventricular derecha conservada, no así en aquellos con disfunción ventricular derecha; análisis de supervivencia con curva de Kaplan-Meier, log rank 6,01, p=0,014. Los pacientes con vmAP ≤ 8 cm/s presentaron niveles plasmáticos menores de Trolox(TM). Los pacientes con mayor concentración de IL-10 presentaron menor incidencia de episodios en el seguimiento. Conclusión: La vmAP es un indicador pronóstico no invasivo precoz en IC con y sin hipertensión pulmonar asociada, previo al desarrollo de disfunción ventricular derecha. La menor concentración de Trolox(TM) en pacientes con vmAP ≤ 8 cm/s refleja un mayor nivel de estrés oxidativo en pacientes de peor pronóstico, mientras que la mayor expresión de IL-10 en pacientes libres de eventos podría guardar relación con su efecto antiinflamatorio y potencialmente protector en IC


Background and objective: To identify early, non-invasive prognostic indicators in heart failure (HF), with and without associated pulmonary hypertension, by means of cardiac magnetic resonance, and oxidative stress and anti-inflammatory biomarkers such as TroloxTM (antioxidant status) and IL-10 (anti-inflammatory cytokine). Patients and methods: We prospectively included 70 patients admitted for new-onset HF. During index admission, mean velocity of the pulmonary artery (mvPA) was measured, and blood TroloxTM and IL-10 determined. The study sample was divided in two groups according to the optimal cut-off value for event prediction calculated by the ROC curve (mvPA=8cm/s), considering HF-readmission and all-cause mortality as the primary combined event. Results: During a median follow-up of 290 days, 16 events occurred. In patients with preserved right ventricular (RV) function, mvPA ≤8cm/s was associated with a higher incidence of events during follow-up, Kaplan-Meier survival analysis (log rank 6.01, p=.014). MvPA did not add prognostic value when RV dysfunction was already established. TroloxTM concentration was lower in patients with mvPA ≤8cm/s. Higher IL-10 expression was associated with a lower incidence of cardiovascular events during follow-up. Conclusion: In HF patients, mvPA ≤8cm/s predicts a higher rate of cardiovascular events. Specifically, mvPA identifies a higher risk population among patients with preserved RV function, thus confirming its role as an early prognostic indicator. Lower TroloxTM concentration in the worse prognosis group concurs with previous studies on oxidative stress in pulmonary hypertension. Higher IL-10 concentration among patients free of cardiovascular events could be a reflection of its anti-inflammatory and thus protective role in HF


Assuntos
Humanos , Insuficiência Cardíaca/diagnóstico por imagem , Prognóstico , Velocidade do Fluxo Sanguíneo , Artéria Pulmonar/diagnóstico por imagem , Estresse Oxidativo , Anti-Inflamatórios , Estudos Prospectivos , Curva ROC , Estimativa de Kaplan-Meier , Autofagia , Fibrilação Atrial , Taxa de Filtração Glomerular , Cateterismo Cardíaco/métodos , Modelos Logísticos , Análise Multivariada
19.
PLoS Comput Biol ; 15(8): e1007259, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31415554

RESUMO

Recent developments in cardiovascular modelling allow us to simulate blood flow in an entire human body. Such model can also be used to create databases of virtual subjects, with sizes limited only by computational resources. In this work, we study if it is possible to estimate cardiovascular health indices using machine learning approaches. In particular, we carry out theoretical assessment of estimating aortic pulse wave velocity, diastolic and systolic blood pressure and stroke volume using pulse transit/arrival timings derived from photopletyshmography signals. For predictions, we train Gaussian process regression using a database of virtual subjects generated with a cardiovascular simulator. Simulated results provides theoretical assessment of accuracy for predictions of the health indices. For instance, aortic pulse wave velocity can be estimated with a high accuracy (r > 0.9) when photopletyshmography is measured from left carotid artery using a combination of foot-to-foot pulse transmit time and peak location derived for the predictions. Similar accuracy can be reached for diastolic blood pressure, but predictions of systolic blood pressure are less accurate (r > 0.75) and the stroke volume predictions are mostly contributed by heart rate.


Assuntos
Pressão Sanguínea , Modelos Cardiovasculares , Análise de Onda de Pulso/estatística & dados numéricos , Aorta/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Biologia Computacional , Simulação por Computador , Bases de Dados Factuais , Humanos , Aprendizado de Máquina , Distribuição Normal , Fotopletismografia/estatística & dados numéricos , Volume Sistólico/fisiologia , Interface Usuário-Computador , Rigidez Vascular , Dispositivos Eletrônicos Vestíveis/estatística & dados numéricos
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