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1.
J Stroke Cerebrovasc Dis ; 30(1): 105450, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33171424

RESUMO

OBJECTIVES: Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass operation is an effective treatment for patients with Moyamoya disease, and the hemodynamic parameters are reported to be improved after operation. However, there is no report concerning hemodynamic changes from the viewpoint of the preoperative anatomical structure of grafts. In this study, we evaluated the correlation between the preoperatively estimated blood flow of the graft obtained through image-based computational fluid dynamics (CFD) analysis and the hemodynamic changes in the acute phase after revascularization. MATERIALS AND METHODS: A total of 30 hemispheric sides of 23 patients were examined. The blood flow, that is, flow rate (FR) of the STA branches that were anastomosed to the MCA was evaluated using CFD analysis based on computed tomography (CT) angiography imaging data. The correlations between the FR and the hemodynamic changes in the acute phase after revascularization obtained through CT perfusion were assessed. RESULTS: The preoperatively estimated FR of the graft was moderately correlated with the changes in the mean transit time significantly and weakly correlated with those in the cerebral blood flow and cerebral blood volume. In addition, the FR was strongly correlated with age and the diameter of the STA from the origin to the bifurcation. CONCLUSION: The preoperatively estimated FR of the graft obtained through image-based CFD analysis contributed to the improvement of the mean transit time after revascularization. Because the FR of the graft was associated with the diameter of the STA, the size of the STA might be an important factor in postoperative hemodynamic changes. This might lead to the risk assessment of acute drastic hemodynamic changes as cerebral hyperperfusion, and consequently, better surgical outcomes might be expected.


Assuntos
Revascularização Cerebral , Circulação Cerebrovascular , Hemodinâmica , Artéria Cerebral Média/cirurgia , Doença de Moyamoya/cirurgia , Artérias Temporais/cirurgia , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo , Angiografia Cerebral , Revascularização Cerebral/efeitos adversos , Criança , Pré-Escolar , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Hidrodinâmica , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Modelos Cardiovasculares , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/fisiopatologia , Modelagem Computacional Específica para o Paciente , Imagem de Perfusão , Valor Preditivo dos Testes , Estudos Retrospectivos , Artérias Temporais/diagnóstico por imagem , Artérias Temporais/fisiopatologia , Resultado do Tratamento , Adulto Jovem
3.
Semin Vasc Surg ; 33(3-4): 36-46, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33308594

RESUMO

Before the development of the first prototype duplex ultrasound scanner at the University of Washington in the late 1970s, the only noninvasive tests available for extracranial carotid artery disease were indirect methods, such as the periorbital Doppler examination and oculoplethysmography. The duplex scanner combined real-time two-dimensional B-mode imaging and pulsed-Doppler flow detection in a single instrument and provided Doppler spectral waveforms from discrete sites within the vessel lumen. Spectral waveforms allowed characterization of the flow patterns and velocity changes associated with normal and diseased arteries. In a series of validation studies, Dr. D. Eugene Strandness, Jr. and colleagues compared various spectral waveform parameters obtained from internal carotid arteries to independently read carotid arteriograms and established quantitative threshold criteria for classification of carotid artery disease. These criteria were based on peak systolic velocity and end-diastolic velocity, as well as features such as spectral broadening and flow separation. Internal carotid arteries were classified as normal, 1% to 15% diameter reduction, 16% to 49% diameter reduction, 50% to 79% diameter reduction, 80% to 99% diameter reduction, and occluded. Since the 1980s, the University of Washington carotid duplex criteria have been widely used and modified in vascular laboratories throughout the world. Additional clinically relevant criteria have also been developed, such as a threshold for the 70% to 99% North American Symptomatic Carotid Endarterectomy Trial (NASCET) stenosis. Validation of carotid criteria has always depended on comparing spectral waveform parameters to the "gold standard" of contrast arteriography. However, experience has shown that the relationship between velocity and arteriographic stenosis is subject to significant variability. Based on these observations, standardization of carotid duplex criteria should lead to more consistent reporting among vascular laboratories, but it is unlikely to result in improved correlation with arteriography.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Ultrassonografia Doppler Dupla , Velocidade do Fluxo Sanguíneo , Artéria Carótida Interna/fisiopatologia , Estenose das Carótidas/história , Estenose das Carótidas/fisiopatologia , História do Século XX , História do Século XXI , Humanos , Valor Preditivo dos Testes , Prognóstico , Fluxo Sanguíneo Regional , Índice de Gravidade de Doença , Ultrassonografia Doppler Dupla/história
4.
Semin Vasc Surg ; 33(3-4): 47-53, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33308595

RESUMO

Duplex ultrasound testing after open or endovascular extracranial carotid artery interventions is a clinical practice guideline with a strong recommendation from the Society for Vascular Surgery. Neurologic outcomes are improved by the recognition of repair site stenosis or atherosclerotic disease progression in the unoperated carotid artery. The benefit of surveillance outweighs its risk because duplex testing is free of complications and accurate in the detection of internal carotid artery (ICA) stenosis or occlusion. Surveillance for >70% ICA stenosis is recommended within 30 days of the procedure, then every 6 months for 2 years, and annually thereafter. Repair site and contralateral ICA stenosis classification should be based on angle-corrected pulsed Doppler measurements of peak systolic velocity (PSV), end-diastolic velocity (EDV), and the ratio of PSV at the stenosis to a proximal, nondiseased common carotid artery (CCA) segment (ICA/CCA ratio). Interpretation criteria of PSV >300 cm/s, EDV >125 cm/s, and ICA/CCA ratio >4 predicts >70% repair site stenosis. Endovascular intervention is recommended for a carotid repair site stenosis based on the occurrence of an ipsilateral neurologic event and appropriate anatomy for angioplasty. For asymptomatic restenosis, intervention is based on stenosis progression to elevated PSV and EDV >70% stenosis threshold values and the patient is deemed high risk for stroke due to contralateral ICA occlusion or incomplete functional patency of the circle of Willis.


Assuntos
Artéria Carótida Interna/cirurgia , Estenose das Carótidas/terapia , Endarterectomia das Carótidas , Procedimentos Endovasculares/instrumentação , Stents , Ultrassonografia Doppler Dupla , Velocidade do Fluxo Sanguíneo , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/fisiopatologia , Endarterectomia das Carótidas/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Valor Preditivo dos Testes , Recidiva , Fluxo Sanguíneo Regional , Resultado do Tratamento
5.
Semin Vasc Surg ; 33(3-4): 65-68, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33308598

RESUMO

Physiologic assessment of lower limb peripheral artery occlusive disease is based on indirect physiologic measurement of ankle-brachial systolic pressure index (ABI) and recording ultrasound tibial artery waveforms. Duplex ultrasound testing affords direct tibial artery imaging and assessment of pulsed-Doppler tibial artery waveforms, which is more accurate then measurement of ABI for peripheral artery occlusive disease severity assessment. Tibial artery peak systolic velocity (PSV) is of particular value in the evaluation of patients with incompressible tibial arteries producing a falsely elevated ABI. Calculation of the ankle-profunda index (average tibial artery PSV/proximal profunda femoris artery PSV) also correlates with ABI reduction and can be used as an additional measure of peripheral artery occlusive disease. Tibial artery PSVs can be used to supplement ABI as an objective outcome measure after peripheral arterial interventions, and this aspect of duplex scanning warrants further clinical research.


Assuntos
Doença Arterial Periférica/diagnóstico por imagem , Artérias da Tíbia/diagnóstico por imagem , Ultrassonografia Doppler Dupla , Índice Tornozelo-Braço , Velocidade do Fluxo Sanguíneo , Humanos , Doença Arterial Periférica/fisiopatologia , Doença Arterial Periférica/terapia , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Artérias da Tíbia/fisiopatologia , Resultado do Tratamento
6.
Medicine (Baltimore) ; 99(52): e23694, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33350749

RESUMO

ABSTRACT: This study aimed to investigate the effects of age on the peak ratio (PR) of ophthalmic artery (OA) Doppler.The initial peak velocity (P1), second peak velocity (P2) and PR of OA were detected by color Doppler ultrasonography in 147 healthy subjects. All of the subjects were divided into 6 groups (G1-G6) according to the age. (G1, 20-29 years; G2, 30-39 years; G3, 40-49 years; G4, 50-59 years; G5, 60-69 years; and G6, 70 years or older). The blood pressure and heart rate were also examined before ultrasonography. The influences of age, blood pressure and heart rate on the P1, P2, and PR were further evaluated.There were significant differences in the P2 and PR among different age groups except for P1. There were no significant differences in the P2 and PR between the first 2 groups, neither among the latter 4 groups. Nevertheless, P2 and PR in the first 2 groups were significantly different from those in the latter 4 groups. In addition, both P2 and PR (not P1) increased significantly with age, systolic and diastolic blood pressure. P1, P2 and PR were not related to heart rate. Both P2 and PR were closely related to the age. PR also had a weak relationship with systolic blood pressure.Both P2 and PR of OA Doppler increase with age. Concern should be raised when P2 and PR are used to evaluate the hemodynamic change of OA.


Assuntos
Artéria Oftálmica/fisiologia , Adulto , Fatores Etários , Idoso , Velocidade do Fluxo Sanguíneo , Feminino , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Artéria Oftálmica/diagnóstico por imagem , Valores de Referência , Fluxo Sanguíneo Regional , Ultrassonografia Doppler em Cores , Adulto Jovem
7.
Int Heart J ; 61(6): 1142-1149, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33191349

RESUMO

Some patients exhibit discrepancies in carotid and coronary artery atherosclerosis. This study aimed to define the characteristics and prognosis of these discrepant patients and determine the best strategy to detect pan-vascular atherosclerosis. A database of 5,022 consecutively registered patients who underwent both coronary angiography and carotid ultrasonography, along with clinical and blood laboratory tests, echocardiography, and pulse wave velocity (PWV), was analyzed. The development of cerebro-cardiovascular (CV) events during the follow-up period was also evaluated. A significant proportion of patients (n = 1,741, 35%) presented with a discrepancy between carotid artery plaque and coronary artery disease (CAD). In patients without carotid plaque, male sex (odds ratio [OR], 1.71; 95% confidence interval [CI], 1.20-2.41; P = 0.003), older age (OR, 1.03; 95% CI, 1.01-1.04; P = 0.002), smoking history (OR, 1.58; 95% CI, 1.13-2.20; P = 0.008), lower high-density lipoprotein (HDL) -cholesterol level (OR, 0.97; 95% CI, 0.96-0.98; P < 0.001), and lower common carotid artery end-diastolic velocity (CCA-EDV) (OR, 0.97; 95% CI, 0.95-0.99; P = 0.005) were independently related to the presence of CAD. In patients without CAD, increased PWV was independently related to the presence of carotid plaque. In survival analysis, patients with isolated CAD had a higher probability of composite CV events; those with isolated carotid plaque had a higher probability of heart failure (HF) and mortality than their counterpart groups (P < 0.05). Even in patients without carotid artery plaque, careful coronary evaluation is needed in older or male patients with smoking history, lower HDL-cholesterol level, or lower CCA-EDV. Carotid plaque may be a potential risk factor for HF.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Mortalidade , Acidente Vascular Cerebral/epidemiologia , Adulto , Fatores Etários , Idoso , Angina Instável/epidemiologia , Índice Tornozelo-Braço , Velocidade do Fluxo Sanguíneo , Doenças Cardiovasculares/mortalidade , Doenças das Artérias Carótidas/epidemiologia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/epidemiologia , HDL-Colesterol/sangue , Angiografia Coronária , Doença da Artéria Coronariana/epidemiologia , Dislipidemias/sangue , Dislipidemias/epidemiologia , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Análise de Onda de Pulso , Estudos Retrospectivos , Fatores Sexuais , Fumar/epidemiologia , Ultrassonografia , Ultrassonografia Doppler , Rigidez Vascular
8.
Int Heart J ; 61(6): 1279-1284, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33191355

RESUMO

Duchenne muscular dystrophy (DMD) is X-linked recessive myopathy caused by mutations in the dystrophin gene. Although conventional treatments have improved their prognosis, inevitable progressive cardiomyopathy is still the leading cause of death in patients with DMD. To explore novel therapeutic options, a suitable animal model with heart involvement has been warranted.We have generated a rat model with an out-of-frame mutation in the dystrophin gene using CRISPR/Cas9 genome editing (DMD rats). The aim of this study was to evaluate their cardiac functions and pathologies to provide baseline data for future experiments developing treatment options for DMD.In comparison with age-matched wild rats, 6-month-old DMD rats showed no significant differences by echocardiographic evaluations. However, 10-month-old DMD rats showed significant deterioration in left ventricular (LV) fractional shortening (P = 0.024), and in tissue Doppler peak systolic velocity (Sa) at the LV lateral wall (P = 0.041) as well as at the right ventricular (RV) free-wall (P = 0.004). These functional findings were consistent with the fibrotic distributions by histological analysis.Although the cardiac phenotype was milder than anticipated, DMD rats showed similar distributions and progression of heart involvement to those of patients with DMD. This animal may be a useful model with which to develop effective drugs and to understand the underlying mechanisms of progressive heart failure in patients with DMD.


Assuntos
Cardiomiopatias/fisiopatologia , Modelos Animais de Doenças , Distrofina/genética , Coração/fisiopatologia , Distrofia Muscular de Duchenne/fisiopatologia , Miocárdio/patologia , Ratos , Fatores Etários , Animais , Velocidade do Fluxo Sanguíneo , Sistemas CRISPR-Cas , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/genética , Cardiomiopatias/patologia , Ecocardiografia , Mutação da Fase de Leitura , Edição de Genes , Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Masculino , Distrofia Muscular de Duchenne/diagnóstico por imagem , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patologia
9.
Am J Physiol Renal Physiol ; 319(6): F1054-F1066, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33135478

RESUMO

In the present study, we demonstrated the marked activity of SW033291, an inhibitor of 15-hydoxyprostaglandin dehydrogenase (15-PGDH), in preventing acute kidney injury (AKI) in a murine model of ischemia-reperfusion injury. AKI due to ischemic injury represents a significant clinical problem. PGE2 is vasodilatory in the kidney, but it is rapidly degraded in vivo due to catabolism by 15-PGDH. We investigated the potential of SW033291, a potent and specific 15-PGDH inhibitor, as prophylactic treatment for ischemic AKI. Prophylactic administration of SW033291 significantly increased renal tissue PGE2 levels and increased post-AKI renal blood flow and renal arteriole area. In parallel, prophylactic SW033291 decreased post-AKI renal morphology injury scores and tubular apoptosis and markedly reduced biomarkers of renal injury that included blood urea nitrogen, creatinine, neutrophil gelatinase-associated lipocalin, and kidney injury molecule-1. Prophylactic SW033291 also reduced post-AKI induction of proinflammatory cytokines, high-mobility group box 1, and malondialdehyde. Protective effects of SW033291 were mediated by PGE2 signaling, as they could be blocked by pharmacological inhibition of PGE2 synthesis. Consistent with activation of PGE2 signaling, SW033291 induced renal levels of both EP4 receptors and cAMP, along with other vasodilatory effectors, including AMP, adenosine, and the adenosine A2A receptor. The protective effects of SW0333291 could largely be achieved with a single prophylactic dose of the drug. Inhibition of 15-PGDH may thus represent a novel strategy for prophylaxis of ischemic AKI in multiple clinical settings, including renal transplantation and cardiovascular surgery.


Assuntos
Lesão Renal Aguda/prevenção & controle , Adenosina/metabolismo , Dinoprostona/metabolismo , Inibidores Enzimáticos/farmacologia , Hidroxiprostaglandina Desidrogenases/antagonistas & inibidores , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Piridinas/farmacologia , Receptor A2A de Adenosina/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Circulação Renal/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Tiofenos/farmacologia , Vasodilatação/efeitos dos fármacos , Lesão Renal Aguda/enzimologia , Lesão Renal Aguda/patologia , Lesão Renal Aguda/fisiopatologia , Animais , Velocidade do Fluxo Sanguíneo , Modelos Animais de Doenças , Hidroxiprostaglandina Desidrogenases/metabolismo , Rim/enzimologia , Rim/patologia , Masculino , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais
10.
Medicine (Baltimore) ; 99(48): e23338, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33235098

RESUMO

We aimed to investigate the correlation of graft flow measurements between transit-time flow measurement (TTFM) during coronary artery bypass grafting (CABG) surgery and dynamic cardiac CT after the surgery.Fourteen patients underwent CABG with TTFM and postoperative dynamic cardiac CT; 11 internal thoracic artery (ITA) grafts and 15 saphenous venous grafts (SVGs) were included for analysis. Pearsons correlation analysis was performed for the comparisons of the TTFM and cardiac dynamic CT flow parameters.TTFM was not significantly correlated with the CT flow of the ITA grafts (r = -0.23, P = .49), but it had a very strong correlation with the CT flow of the SVGs (r = 0.83, P < .01).In patients who underwent CABG surgery, dynamic cardiac CT enabled quantitative evaluation of SVG flow, with good correlation with TTFM.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Ponte de Artéria Coronária/métodos , Artéria Torácica Interna/cirurgia , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Veia Safena/transplante , Tomografia Computadorizada por Raios X/normas
11.
Nat Commun ; 11(1): 6020, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243995

RESUMO

Understanding the structure and function of vasculature in the brain requires us to monitor distributed hemodynamics at high spatial and temporal resolution in three-dimensional (3D) volumes in vivo. Currently, a volumetric vasculature imaging method with sub-capillary spatial resolution and blood flow-resolving speed is lacking. Here, using two-photon laser scanning microscopy (TPLSM) with an axially extended Bessel focus, we capture volumetric hemodynamics in the awake mouse brain at a spatiotemporal resolution sufficient for measuring capillary size and blood flow. With Bessel TPLSM, the fluorescence signal of a vessel becomes proportional to its size, which enables convenient intensity-based analysis of vessel dilation and constriction dynamics in large volumes. We observe entrainment of vasodilation and vasoconstriction with pupil diameter and measure 3D blood flow at 99 volumes/second. Demonstrating high-throughput monitoring of hemodynamics in the awake brain, we expect Bessel TPLSM to make broad impacts on neurovasculature research.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Microscopia Intravital/métodos , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/irrigação sanguínea , Estudos de Viabilidade , Microscopia Intravital/instrumentação , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Modelos Animais , Pupila/fisiologia , Técnicas Estereotáxicas , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Vigília/fisiologia
12.
J Vis Exp ; (164)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33135687

RESUMO

The pulsed-Doppler effect is the main technique used in clinical echography to assess blood flow. Applied with conventional focused ultrasound Doppler modes, it has several limits. Firstly, a finely tuned signal filtering operation is needed to distinguish blood flows from surrounding moving tissues. Secondly, the operator must choose between localizing the blood flows or quantifying them. In the last two decades, ultrasound imaging has undergone a paradigm shift with the emergence of ultrafast ultrasound using unfocused waves. In addition to a hundredfold increase in framerate (up to 10000 Hz), this new technique also breaks the conventional quantification/localization trade-off, offering a complete blood flow mapping of the field of view and a simultaneous access to fine velocities measurements at the single-pixel level (down to 50 µm). This data continuity in both spatial and temporal dimensions strongly improves the tissue/blood filtering process, which results in an increase sensitivity to small blood flow velocities (down to 1 mm/s). In this method paper, we aim to introduce the concept of ultrafast Doppler as well as its main parameters. Firstly, we summarize the physical principles of unfocused wave imaging. Then, we present the Doppler signal processing main steps. Particularly, we explain the practical implementation of the critical tissue/blood flow separation algorithms and on the extraction of velocities from these filtered data. This theoretical description is supplemented by in vitro experiences. A tissue phantom embedding a canal with flowing blood-mimicking fluid is imaged with a research programmable ultrasound system. A blood flow image is obtained and the flow characteristics are displayed for several pixels in the canal. Finally, a review of in vivo applications is proposed, showing examples in several organs such as carotids, kidney, thyroid, brain and heart.


Assuntos
Circulação Sanguínea/fisiologia , Processamento de Imagem Assistida por Computador , Ultrassonografia Doppler/métodos , Adulto , Algoritmos , Velocidade do Fluxo Sanguíneo/fisiologia , Hemodinâmica , Humanos , Recém-Nascido , Imagens de Fantasmas
13.
Pol Merkur Lekarski ; 48(287): 312-317, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33130789

RESUMO

There are currently insufficient study and analysis of changes in cerebral hemodynamics of boxers who have suffered repeated traumatic brain injury (TBI). To identify such changes, the most informative is the study of blood flow in the vessels of the neck and head using ultrasound duplex scanning (USDS) of the main vessels of the neck and transcranial duplex scanning (TCDS). AIM: The aim of study was to investigate the features of cerebral hemodynamics in boxers with repeated TBI. MATERIALS AND METHODS: A study of blood flow in the vessels of the neck and head was performed for 156 amateur boxers aged 16 to 42 years who had a history of repeated TBI. In the control group, 30 practically healthy people of a similar age were examined. Patients were analyzed by gender and the number of fights held. Obtained results were analyzed statistically. RESULTS: Boxers who have had a history of repeated TBI have hemodynamic disorders. They are characterized by an increase in the velocity of blood flow in extracranial vessels of the carotid basin and a decrease in the vessels of the vertebrobasilar basin with a change in the indicators of vascular resistance. For vessels of the intracranial section of the carotid basin, a decrease in blood flow velocity without changes in the indicators of vascular resistance was typical. Disorders of venous cerebral circulation was noted in most boxers, which was manifested by an increase in speed indicators in the internal jugular vein and veins of Rosenthal. CONCLUSIONS: The study of features of the cerebral hemodynamic in boxers with repeated TBI allows them to predict their competitive activity, correctly select the appropriate therapy and recommendations of the sports regime to prevent possible long-term consequences of injury.


Assuntos
Lesões Encefálicas Traumáticas , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Circulação Cerebrovascular , Hemodinâmica , Humanos , Ultrassonografia , Adulto Jovem
14.
Kardiologiia ; 60(8): 54-64, 2020 Sep 17.
Artigo em Russo | MEDLINE | ID: mdl-33155959

RESUMO

Aim      Comprehensive evaluation of blood flow in the thoracic aorta using a software for 4D processing of magnetic resonance (MR) images of the heart and blood vessels (4D Flow) in patients with aortic coarctation in the late postoperative period.Materials and methods The MR study of the heart was performed for 10 patients (7 boys and 3 girls) aged 8 to 13 years (median, 9.5 [8.3; 10.8] years) who underwent resection with end-to-end anastomosis for aortic coarctation at age of 2 weeks to 10 months. MR tomography was performed on a 1.5 T MR scanner using a multichannel surface coil for scanning, electrocardiographic synchronization, and a specialized package of pulse sequences for scanning of the heart. Blood flow was evaluated with a 4D data handling software for processing of MR images of heart and blood vessels (4D Flow). The following blood flow parameters were analyzed: blood flow volume per second, peak blood flow velocity, peak and minimum blood flow area at the levels of ascending aorta, arch, isthmus, and descending aorta, and pressure gradient at the level of maximum narrowing of the aorta. 3D-MR images were used for evaluation of aortic geometry. Blood flow formation, distribution, and trajectories were analyzed by maps of vectors, particle trace, and stream lines. Statistical analysis was performed with a Statistica (v. 6.0 StatSoft Inc.) package.Results Accelerated flow in the region of residual aortic stenosis in systole was observed in all patients; 4 patients had an additional vortex flow below the aortic stenosis and a spiral flow in the descending aorta. The pressure gradient on the aortic isthmus was directly correlated with the left ventricular myocardial mass index (r=0.65; р=0.04) and indexes of blood flow in the ascending and descending aorta (р=0.03; р=0.026). No significant correlation was found for blood flow indexes and geometry of the aortic arch (H / L). Delayed contrast enhancement MR imaging did not detect any fibrotic changes in the myocardium in only one patient. The fibrosis severity inversely correlated with the right ventricular ejection fraction (r=0.65; р=0.04) and directly correlated with the pressure gradient at the aortic isthmus (r=0.63; p=0.05).Conclusion      The 4D MR image processing software for the heart and blood vessels allows studying the blood flow in detail under natural conditions, provides potential advantages in comprehensive evaluation of patients with aortic coarctation during a dynamic follow-up. For a definitive conclusion about the relationship between the altered blood flow in the thoracic aorta and markers of residual, post-correction pathology, larger studies are required as well as long-term follow-up of patients with documented pathological patterns of blood flow (changes in blood flow velocity and volume throughout the entire thoracic aorta in combination with disorders in the normal flow geometry during the cardiac cycle).


Assuntos
Coartação Aórtica , Adolescente , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Coartação Aórtica/diagnóstico por imagem , Coartação Aórtica/cirurgia , Velocidade do Fluxo Sanguíneo , Criança , Feminino , Humanos , Recém-Nascido , Imagem por Ressonância Magnética , Masculino , Volume Sistólico , Função Ventricular Direita
15.
Zhonghua Yi Xue Za Zhi ; 100(41): 3246-3249, 2020 Nov 10.
Artigo em Chinês | MEDLINE | ID: mdl-33167112

RESUMO

Objective: To analyze the mechanism of invasive blood pressure change in radial artery caused by arm elevation by observing pressure, velocity and diameter of radial artery. Methods: Twenty-six hemodynamically stable hepatobiliary surgery patients admitted to the intensive care unit from June to December 2018 after general anesthesia in Tsinghua Changgung Hospital were selected. When the arm was raised, the invasive blood pressure was recorded, and the inner diameter and blood flow velocity of the radial artery were measured by Doppler ultrasound. The data following a normal distribution were compared with paired t test. Results: After arm elevation for 30 s, systolic blood pressure of radial artery decreased and diastolic blood pressure increased significantly((107±16) mmHg vs (120±17) mmHg, (75±6) mmHg vs (71±9) mmHg, t=25.0, -12.6, both P<0.05), but there was no significant difference in mean arterial pressure ((87±10) mmHg vs (87±11) mmHg, t=1.1, P>0.05). The peak velocity, end-diastolic velocity and resistance index of the radial artery increased significantly, and the transverse and longitudinal inner diameters of the radial artery decreased significantly after the arm was elevated for 30 s (t=-63.4, -14.6, -22.5, 31.4, 25.3, all P<0.01). Conclusions: Kinetic pressure compensation and vascular resistance compensation may be the main mechanism of radial artery pressure change when the arm is elevated. Arm elevation can be used as a vascular resistance response test clinically.


Assuntos
Pressão Arterial , Hidrodinâmica , Braço , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Determinação da Pressão Arterial , Humanos , Artéria Radial
16.
Cerebrovasc Dis ; 49(5): 481-486, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33075786

RESUMO

BACKGROUND: Cerebral small vessel disease (SVD) lesions on MRI are common in patients with cognitive impairment. It has been suggested that cerebral hypoperfusion is involved in the etiology of these lesions. OBJECTIVE: The aim of the study was to determine the relationship between cerebral blood flow (CBF) and SVD burden in patients referred to a memory clinic with SVD on MRI. METHOD: We included 132 memory clinic patients (mean age 73 ± 10, 56% male) with SVD on MRI. We excluded patients with large non-lacunar cortical infarcts. Global CBF (mL/min per 100 mL of brain tissue) was derived from 2-dimensional phase-contrast MRI focused on the internal carotid arteries and the basilar artery. SVD burden was defined as the sum of (each 1 point): white matter hyperintensities (WMHs) Fazekas 1 or more, lacunes, microbleeds (MBs), or enlarged perivascular spaces (PVS) presence, and each SVD feature separately. Linear regression analyses were performed to study the association between CBF and SVD burden, age- and sex-adjusted. RESULTS: Median SVD burden score was 2, 36.4% of patients had MBs, 35.6% lacunar infarcts, 48.4% intermediate to severe enlarged PVS, and 57.6% a WMH Fazekas score 2 or more. Median WMH volume was 21.4 mL (25% quartile: 9.6 mL, 75% quartile: 32.5 mL). Mean CBF ± SD was 44.0 ± 11.9 mL/min per 100 mL brain. There was no relation between CBF and overall SVD burden (CBF difference per burden score point [95% CI]: -0.5 [-2.4; 1.4] mL/min/100 mL brain, p = 0.9). CBF did also not differ according to presence or absence or an high burden of any of the individual SVD features. Moreover, there was no significant relation between WMH volume and CBF (CBF difference per ml increase in WMH [95% CI] -0.6 [-1.5; 0.3] mL/min/100 mL brain p = 0.2). CONCLUSION: Global CBF was not related to overall SVD burden or with individual SVD features in this memory clinic cohort, indicating that in this setting these lesions were not primarily due to cerebral hypoperfusion.


Assuntos
Doenças de Pequenos Vasos Cerebrais/complicações , Circulação Cerebrovascular , Cognição , Disfunção Cognitiva/etiologia , Transtornos da Memória/etiologia , Memória , Acidente Vascular Cerebral Lacunar/complicações , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Transtornos da Memória/diagnóstico , Transtornos da Memória/psicologia , Pessoa de Meia-Idade , Ambulatório Hospitalar , Imagem de Perfusão , Encaminhamento e Consulta , Fatores de Risco , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Acidente Vascular Cerebral Lacunar/fisiopatologia
17.
Br J Anaesth ; 125(6): 1064-1069, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33012517

RESUMO

BACKGROUND: High-volume (1.5 ml kg-1) caudal block in infants results in major reductions of cerebral blood flow velocity (CBFV) and cerebral oxygenation, caused by rostral CSF movement which increases intracranial pressure. The primary aim of this study was to determine the relationship between injected volume and CBFV changes. We hypothesised that this volume-blood flow relationship would have a similar albeit inverted shape to the well-known intracranial pressure volume-pressure curve. METHODS: Fifteen subjects, age 0-6 months, mean (range) weight 4.9 (2.1-6.4) kg, were studied. A 1.5 ml kg-1 caudal injection of 0.2% ropivacaine was administered in three phases separated by two pauses. Subjects were randomised into five groups, in whom the pauses were implemented at different pre-set proportions of the total injected volume. Middle cerebral artery Doppler ultrasonography was used for CBFV measurements (Vmax, peak CBF velocity; Vmin, lowest CBF velocity; velocity time index). Mean flow velocity, pulsatility index, and resistivity index were calculated, and haemodynamic parameters were recorded. RESULTS: CBFV parameters decreased in all patients. The most affected parameter, Vmin, was reduced by ∼50% (range 15-68%) compared with baseline. There was a nonlinear relationship between the volume of the first phase injection and the CBFV measurement during the first pause. Across all time points, there was a linear relationship between volume administered and CBFV. Systemic haemodynamic parameters remained stable throughout the study. CONCLUSIONS: Injection pauses appear to attenuate adverse CBFV increases during administration of a high-volume caudal block.


Assuntos
Anestesia Caudal/métodos , Circulação Cerebrovascular/efeitos dos fármacos , Ropivacaina/farmacologia , Anestésicos Locais/farmacologia , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/efeitos dos fármacos , Ultrassonografia Doppler Transcraniana/métodos
18.
J Stroke Cerebrovasc Dis ; 29(11): 105243, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33066951

RESUMO

OBJECTIVE: Concomitant cerebral infarction (CI) is could be a potential concern in experimental subarachnoid hemorrhage (SAH) induced by endovascular perforation. We propose a noninvasive method for excluding CI in a murine SAH model by using Laser speckle flow imaging (LSFI). METHODS: An SAH was induced with endovascular perforation (EVP) in male ddY mice. The cerebral blood flow (CBF) was quantitatively measured in the bilateral cerebral cortex was performed by using LSFI at five timepoints (preprocedure, immediately after, and 3 hours, 6 hours, and 24 hours after the procedure). The mice were then euthanized, and the SAH grade and volume of the CI were evaluated. The mice were divided into the SAH group and the SAH + CI group. Differences between the groups were assessed. RESULTS: Forty-eight mice were used in this study. Six were the sham control group. Five SAH mice died within 24 hours after the procedure. A large CI on the ipsilateral side occurred in 15 (40.5%) mice (i.e., SAH + CI group). The remaining 22 (59.5%) mice were classified as the SAH group. The SAH grading score was not significantly different between the groups. The neurological score and CBF of the ipsilateral hemisphere were significantly higher in the SAH group than in the SAH + CI group (neurological score: 12.3 vs. 8, p < 0.01; CBF: 343.1 vs. 205.5; p < 0.01). The cut-off modified neurological score for excluding CI was 8 (area under the curve [AUC]: 0.77) and CBF at 24 hours after the procedure was 279.2 (AUC:0.856). CONCLUSIONS: Using LSFI is less invasive and effectively excludes concomitant CI in experimental SAH. This methodological protocol may ad in improving the quality of the EVP-SAH model.


Assuntos
Infarto Cerebral/diagnóstico por imagem , Circulação Cerebrovascular , Procedimentos Endovasculares , Fluxometria por Laser-Doppler , Hemorragia Subaracnóidea/diagnóstico por imagem , Animais , Comportamento Animal , Velocidade do Fluxo Sanguíneo , Infarto Cerebral/etiologia , Infarto Cerebral/patologia , Infarto Cerebral/fisiopatologia , Modelos Animais de Doenças , Masculino , Camundongos , Atividade Motora , Valor Preditivo dos Testes , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/patologia , Hemorragia Subaracnóidea/fisiopatologia , Fatores de Tempo
19.
J Cardiovasc Magn Reson ; 22(1): 72, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33012283

RESUMO

BACKGROUND: The aim of this study is to quantify the frequency content of the blood velocity waveform in different body regions by means of phase contrast (PC) cardiovascular magnetic resonance (CMR) and Doppler ultrasound. The highest frequency component of the spectrum is inversely proportional to the ideal temporal resolution to be used for the acquisition of flow-sensitive imaging (Shannon-Nyquist theorem). METHODS: Ten healthy subjects (median age 33y, range 24-40) were scanned with a high-temporal-resolution PC-CMR and with Doppler ultrasound on three body regions (carotid arteries, aorta and femoral arteries). Furthermore, 111 patients (median age 61y) with mild to moderate arterial hypertension and 58 patients with aortic aregurgitation, atrial septal defect, or repaired tetralogy of Fallot underwent aortic CMR scanning. The frequency power distribution was calculated for each location and the maximum frequency component, fmax, was extracted and expected limits for the general population were inferred. RESULTS: In the healthy subject cohort, significantly different fmax values were found across the different body locations, but they were nonsignificant across modalities. No significant correlation was found with heart rate. The measured fmax ranged from 7.7 ± 1.1 Hz in the ascending aorta, up to 12.3 ± 5.1 Hz in the femoral artery (considering PC-CMR data). The calculated upper boundary for the general population ranged from 11.0 Hz to 27.5 Hz, corresponding to optimal temporal resolutions of 45 ms and 18 ms, respectively. The patient cohort exhibited similar values for the frequencies in the aorta, with no correlation between blood pressure and frequency content. CONCLUSIONS: The temporal resolution of PC-CMR acquisitions can be adapted based on the scanned body region and in the adult population, should approach approximately 20 ms in the peripheral arteries and 40 ms in the aorta. TRIAL REGISTRATION: This study presents results from a restrospective analysis of the clinical study NCT01870739 (ClinicalTrials.gov).


Assuntos
Aorta/diagnóstico por imagem , Doenças Cardiovasculares/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Artéria Femoral/diagnóstico por imagem , Imagem por Ressonância Magnética , Ultrassonografia Doppler , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta/fisiopatologia , Velocidade do Fluxo Sanguíneo , Doenças Cardiovasculares/fisiopatologia , Artérias Carótidas/fisiopatologia , Feminino , Artéria Femoral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
20.
Arq Bras Cardiol ; 115(3): 503-512, 2020 09.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33027374

RESUMO

BACKGROUND: TIMI flow grade and corrected TIMI frame count (CTFC) are widely used methods to evaluate angiographic coronary blood flow. Measurement of coronary blood flow (CBF) on standard coronary angiography (CAG) has aroused great interest recently, trying to combine the CTFC concept with new methods for post-angioplasty and for cardiac syndrome X assessment. Additionally, coronary slow flow it is now considered a major criterion for microvascular angina. OBJECTIVE: Explore a new approach of quantitative angiographic measurement of CBF based on densitometric contrast detection in CAG off-line, using an accessible software to obtain a more precise and reliable CBF assessment. METHODS: Thirty patients were studied and divided in 2 groups, normal coronary blood flow (NF) and slow coronary blood flow (SF), according to CTFC definition. The DM was applied to the study sample to differentiate between NF and SF. Non-parametric statistics was used to assess differences between groups at p<0.05. RESULTS: The DM normal reference value obtained for coronary blood flow was 9 [5-10] frames. NF vs SF group were compared and expressed as median [interquartile range], for the left anterior descending: 10 [7-11] vs 21 [8-33];p= 0.016; circumflex: 9 [4-13] vs 14 [11-30]; p= 0.012 and right coronary artery: 5 [3-11] vs 13 [8-26]; p=0.009. CONCLUSION: The DM showed the feasibility of measuring coronary blood flow with precision, consistency and reproducible in a standard coronary angiogram, showing the additional capability to differentiate between NF and SF in chest pain patients with normal coronary arteries. (Arq Bras Cardiol. 2020; 115(3):503-512).


Assuntos
Circulação Coronária , Angina Microvascular , Velocidade do Fluxo Sanguíneo , Angiografia Coronária , Hemodinâmica , Humanos
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