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ABC., imagem cardiovasc ; 35(2): eabc304, 2022. ilus, tab
Article in Portuguese | LILACS | ID: biblio-1400334


Introdução: A função sistodiastólica do ventrículo esquerdo é prognóstica nas doenças cardiovasculares e pode ser avaliada por strain longitudinal global por meio de ecocardiografia e de ressonância magnética cardíaca. O strain longitudinal global pela ressonância magnética cardíaca exige a utilização de software de alto custo. O deslocamento linear longitudinal do ventrículo esquerdo pode ser uma alternativa simples e barata ao strain longitudinal global, porém eles não foram ainda comparados sistematicamente. Objetivo: Comparar o deslocamento linear longitudinal com o strain longitudinal global e fração de ejeção do ventrículo esquerdo em valvopatas aórticos e controles. Métodos: Incluímos 44 participantes (26 valvopatas aórticos/19 controles). O strain longitudinal global utilizou software específico (Circle Cardiovascular Imaging 42) e o deslocamento linear longitudinal apenas medidas lineares de distância entre a base e o ápex do ventrículo esquerdo, gerando deslocamento máximo, velocidade máxima no início da diástole, velocidade na diástase e a relação entre velocidade na diástase e velocidade máxima no início da diástole. Resultados: Deslocamento máximo e velocidade máxima no início da diástole correlacionaram-se com strain longitudinal global (r=0,69 e r=0,65 respectivamente) e com a fração de ejeção do ventrículo esquerdo (r=0,47 e r=0,57, p<0,001 para ambos). Deslocamento máximo e velocidade máxima no início da diástole apresentaram área sob a curva Característica de Operação do Receptor de 0,88 e 0,91 e, no melhor ponto de corte (-0,13 e 0,66), sensibilidade de 72,43% e 57,14% e especificidade 80,65% e 87,10%, respectivamente, quando comparados ao strain longitudinal global. Utilizando a fração de ejeção do ventrículo esquerdo como referência, foram obtidos 0,70 e 0,82, e, no melhor ponto de corte (-0,11 e 0,61), sensibilidade de 75,00% e 50,00% e especificidade 72,97% e 78,38%, respectivamente. Conclusão: O deslocamento linear longitudinal foi semelhante ao strain longitudinal global. O deslocamento máximo derivado do deslocamento linear longitudinal foi o melhor parâmetro na sístole, enquanto a velocidade máxima no início da diástole foi o melhor na diástole, o que possibilita a avaliação da função diastólica pela ressonância magnética cardíaca na rotina clínica de forma rápida e sem custo adicional.(AU)

Background: Left ventricular (LV) systolic diastolic function is prognostic in cardiovascular diseases and can be assessed via global longitudinal strain (GLS) on echocardiography and cardiac magnetic resonance (CMR). However, GLS by CMR requires the use of expensive software. Longitudinal linear displacement (LLD) may be a simple and inexpensive alternative to GLS, but the two have not been systematically compared. Objective: To compare LLD with GLS and LV ejection fraction (LVEF) in aortic valve disease patients and controls. Methods: We included 44 participants (26 with aortic valve disease, 19 controls). GLS was determined using CVI42 software (Circle Cardiovascular Imaging), while the LLD linear measurements of the distance between the base/apex of the LV included maximum displacement (MD), maximum velocity in early diastole (MVED), atrioventricular junction velocity in diastasis (VDS), and VDS/MVED ratio. Results: DM and MVED were correlated with GLS (r=0.69 and r=0.65, respectively) and LVEF (r=0.47 and r=0.57, p<0.001 for both). DM and MVED showed areas under the receiver operating characteristic curve (AUC) of 0.88 and 0.91, and at the best cut-off point (-0.13 and 0.66), sensitivities of 72.43% and 57.14% and specificities of 80.65% and 87.10%, respectively, compared to GLS. Using LVEF as a reference, we obtained AUC of 0.70 and 0.82, and at the best cut-off point (-0.11 and 0.61), sensitivities of 75.00% and 50.00% and specificities of 72.97% and 78.38%, respectively. Conclusion: LLD demonstrated similar performance to that of GLS. MD derived from LLD was the best parameter during systole, while MVED was the best during diastole. Our findings demonstrate the routine, quick, and inexpensive assessment of diastolic function on CMR.(AU)

Humans , Male , Female , Adult , Middle Aged , Aged , Stroke Volume/physiology , Echocardiography/methods , Ventricular Function, Left , Aortic Valve Disease/diagnosis , Myocardial Contraction/physiology , Aortic Valve Insufficiency/diagnostic imaging , Blood Flow Velocity , Magnetic Resonance Spectroscopy/methods , Heart Ventricles/pathology
Ann. Health Res. (Onabanjo Univ. Teach. Hosp.) ; 8(1): 49-62, 2022. figures, tables
Article in English | AIM | ID: biblio-1362843


Background:The co-existence of diabetes mellitus (DM) and hypertension (HTN) has been rising globally with subclinical atherosclerotic complications. These vascular changes can be detected using carotid ultrasonography. Objectives: To determine and compare the carotid arterial structural wall changes and blood flow velocities of adults with co-existing DM and HTN with age-and sex-matched non-diabetic, non-hypertensive controls. Methods: A cross-sectional comparative study of 300 participants comprising 200 adults with co-existing DM and HTN and 100 age-and sex-matched controls was done. Their carotid arteries were examined bilaterally for plaques, carotid intima media thickness (CIMT) and flow velocities ­peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistive index (RI) using 4­12MHz linear array transducer. Visceral obesity and serum lipids were also assessed. Results: The mean age of the subjects was 56.13 ± 6.93 years; they comprised 38% males and 62% females. The subjects' CIMT was statistically significantly higher (p = 0.001) with a three-fold mean increase (45.5%) compared to the controls (13.7%). Lower flow velocities but higher indices were also observed in the subjects. Strong and significant correlations were observed between EDV and PI r =-0.663, p=>0.001), EDV and RI (r = -0.661, p=>0.001) and PI and RI (r =0.988, p= >0.001)among the subjects. Conclusion: Significant reduction in flow velocities with increased CIMT may be an early indication of subclinical atherosclerosis. Therefore, carotid ultrasonography should be mandatory in individuals at risk for early detection and possible prevention of atherosclerotic complications.

Humans , Male , Female , Middle Aged , Blood Flow Velocity , Carotid Artery Diseases , Ultrasonography, Doppler , Diabetes Mellitus, Type 2 , Hypertension
Article in Chinese | WPRIM | ID: wpr-928200


It has been found that the incidence of cardiovascular disease in patients with lower limb amputation is significantly higher than that in normal individuals, but the relationship between lower limb amputation and the episodes of cardiovascular disease has not been studied from the perspective of hemodynamics. In this paper, numerical simulation was used to study the effects of amputation on aortic hemodynamics by changing peripheral impedance and capacitance. The final results showed that after amputation, the aortic blood pressure increased, the time averaged wall shear stress of the infrarenal abdominal aorta decreased and the oscillatory shear index of the left and right sides was asymmetrically distributed, while the time averaged wall shear stress of the iliac artery decreased and the oscillatory shear index increased. The changes above were more significant with the increase of amputation level, which will result in a higher incidence of atherosclerosis and abdominal aortic aneurysm. These findings preliminarily revealed the influence of lower limb amputation on the occurrence of cardiovascular diseases, and provided theoretical guidance for the design of rehabilitation training and the optimization of cardiovascular diseases treatment.

Amputation, Surgical , Aorta, Abdominal/surgery , Aortic Aneurysm, Abdominal/surgery , Blood Flow Velocity/physiology , Hemodynamics/physiology , Humans , Lower Extremity , Models, Cardiovascular , Stress, Mechanical
Acta cir. bras ; 37(6): e370604, 2022. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1402961


Purpose: To evaluate the caliber of an arterial micro-anastomosis in the young growing animal using a continuous suture technique. Additionally, late morphological changes and blood flows distal to the anastomosis were evaluated. Methods: Seventy-four Wistar rats were submitted to laparotomy to access the aorta for blood flow measurement. The aorta was sectioned using microsurgery technique and an end-to-end anastomosis with continuous suture. After a period of six months to one year, the anastomosis was checked. Results: Regarding the size of the aortas, comparing the pre- and postoperative values, there was an increase of 13.33% in adult animals and 25% in young animals, without any difference in the blood flows. Conclusions: The arteries of young rats show signs of growth at the site of the anastomosis performed with continuous suture.

Animals , Rats , Blood Flow Velocity , Anastomosis, Surgical/veterinary , Microsurgery/veterinary , Suture Techniques/veterinary , Rats, Wistar/surgery
Article in Chinese | WPRIM | ID: wpr-928883


Echocardiogram is vital for the diagnosis of cardiac disease. The heart has complex hemodynamics requiring an advanced ultrasound imaging mode. Cardiac ultrasound vector flow imaging is capable of measuring the actual magnitude and direction of the blood flow velocity, obtaining the quantitative parameters of hemodynamics, and then providing more information for clinical research and diagnosis. This study mainly reviewed several different vector flow imaging techniques for cardiac flow and presented the implementation difficulties, and proposed a diverging wave based high frame rate cardiac ultrasound vector flow imaging. The study discussed the limitation of current ultrasound technology used in the cardiac flow measurement, analyzed and demonstrated the specific reasons for these implementation difficulties and the potential future development.

Blood Flow Velocity , Heart/physiology , Hemodynamics , Ultrasonography
Article in Chinese | WPRIM | ID: wpr-928875


By using Doppler sensor and pressure sensor, the cerebrovascular stroke detector can be used to measure the blood flow velocity and blood pressure of the carotid artery. In this study, a variety of signal conversion and isolation processing techniques are proposed for processing and feature extraction of the output signals from the sensors. Finally, effective signal output waveforms that can be used to evaluate the cerebrovascular hemodynamics index (CVHI) are obtained, and the sound signal outputs that can reflect the change characteristics of blood flow velocity and blood pressure signals are generated, which realizes the application functional requirements of the detector.

Blood Flow Velocity/physiology , Cerebrovascular Circulation/physiology , Hemodynamics/physiology , Humans , Stroke , Technology
Article in Chinese | WPRIM | ID: wpr-939624


Blood velocity inversion based on magnetoelectric effect is helpful for the development of daily monitoring of vascular stenosis, but the accuracy of blood velocity inversion and imaging resolution still need to be improved. Therefore, a convolutional neural network (CNN) based inversion imaging method for intravascular blood flow velocity was proposed in this paper. Firstly, unsupervised learning CNN is constructed to extract weight matrix representation information to preprocess voltage data. Then the preprocessing results are input to supervised learning CNN, and the blood flow velocity value is output by nonlinear mapping. Finally, angiographic images are obtained. In this paper, the validity of the proposed method is verified by constructing data set. The results show that the correlation coefficients of blood velocity inversion in vessel location and stenosis test are 0.884 4 and 0.972 1, respectively. The above research shows that the proposed method can effectively reduce the information loss during the inversion process and improve the inversion accuracy and imaging resolution, which is expected to assist clinical diagnosis.

Angiography , Blood Flow Velocity , Constriction, Pathologic , Humans , Neural Networks, Computer
Rev. chil. obstet. ginecol. (En línea) ; 86(3): 258-264, jun. 2021. ilus, tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1388659


INTRODUCCIÓN: La aneuploidía más común entre los recién nacidos vivos es el síndrome de Down (SD). En estos niños el crecimiento está disminuido, con una frecuencia del 25% de restricción del crecimiento intrauterino, pero no se ha establecido el papel de la insuficiencia placentaria. El objetivo es estudiar la resistencia placentaria a través del Doppler de arteria umbilical con índice de pulsatilidad (IP) y el tiempo medio de desaceleración (t/2), y el posible efecto de la insuficiencia placentaria en fetos con SD. MÉTODO: Se realizó Doppler en la arteria umbilical en 78 fetos con SD, se midieron el IP y el t/2, y se compararon los resultados con los pesos de nacimiento. RESULTADOS: Se estudiaron 78 fetos con SD con 214 mediciones Doppler. El t/2 y el IP estaban alterados en el 71,5% y el 65% de las mediciones, respectivamente. La incidencia de t/2 alterado aumenta con la edad gestacional desde un 28,6% a las 15-20 semanas hasta un 89,3% sobre las 36 semanas (p < 0,01); cifras similares se observan para el IP. La clasificación de los pesos fue: 64% adecuados, 12% grandes y 24% pequeños para la edad gestacional. La última medición de t/2 antes del parto era normal en el 17% y estaba alterada en el 83%. En el caso del IP, los valores fueron normales en el 27% y anormales en el 73%. El peso de nacimiento, la edad gestacional y el porcentaje de niños adecuados para la edad gestacional eran significativamente mayores en el grupo con Doppler normal que en el grupo con Doppler alterado. El z-score del t/2 estaba marcadamente alterado (−2.23), pero el del peso de nacimiento solo estaba algo disminuido (−0,39). La mortalidad perinatal fue del 10%, significativamente mayor cuando el flujo diastólico era ausente o reverso. CONCLUSIONES: El estudio demuestra que los fetos con SD tienen una alta incidencia de alteración del Doppler umbilical para el IP y el t/2, lo cual sugiere una insuficiencia placentaria grave. Este deterioro parece iniciarse hacia el final del segundo trimestre y aumenta con la edad gestacional. Sin embargo, en estos fetos, la insuficiencia placentaria produce una ligera caída en el crecimiento fetal. Como hipótesis general pensamos que en los fetos con SD hay datos claros de insuficiencia placentaria, pero habría algún factor que les protegería de una restricción grave del crecimiento.

INTRODUCTION: The most common aneuploidy in live newborns is Down syndrome (DS), in these children growth is decreased, with a frequency of 25-36% of fetal growth restriction (FGR); however, it is not established the role of placental insufficiency. The objective is to study the Doppler of the umbilical artery with pulsatility index (PI) and half peak systolic velocity (hPSV) deceleration time and the possible role of placental insufficiency in fetuses with DS. METHOD: Doppler was performed in fetuses with DS, the umbilical artery and IP and hPSV were measured, and the results were compared with birth weights. RESULTS: 78 fetuses with DS were studied with 214 Doppler measurements. hPSV and the IP were altered in 71.5% and 65% of the measurements; the incidence of abnormal hPSV increases with gestational age from 28.6% between 15 to 20 weeks, to 89.3% over 36 weeks (p < 0.01), similar figures are observed with respect to the PI. The weight classification was: 24% of FGR, 12% of great for age and 64% of adequate for gestational age (AGA). The last measurement of hPSV before delivery was normal in 17% of the fetuses and was abnormal in 83%, in the case of PI the normal and abnormal values were 27 and 73%, respectively. Birth weight, gestational age, and the percentage of AGA children were significantly higher in the normal Doppler group than in the abnormal Doppler group. The hPSV z-score was markedly altered (−2.23), but the birth weight z-score is slightly decreased (−0.39). Perinatal mortality is 10% and is significantly higher when diastolic flow is absent or reverse. CONCLUSIONS: The study shows that DS fetuses have a high incidence of abnormal umbilical Doppler measured with IP and hPSV, which suggests severe placental insufficiency, this deterioration seems to start towards the end of the second trimester and increases with gestational age. However, in these fetuses, placental insufficiency causes a discrete drop in fetal growth. As a general hypothesis, we think that there is clear evidence of placental insufficiency in fetuses with DS, but there would be some factor that would protect these fetuses from severe growth restriction.

Humans , Female , Pregnancy , Umbilical Arteries/diagnostic imaging , Down Syndrome/diagnostic imaging , Placental Insufficiency/etiology , Blood Flow Velocity , Pulsatile Flow , Ultrasonography, Prenatal , Gestational Age , Ultrasonography, Doppler , Deceleration , Fetal Growth Retardation/etiology
J. vasc. bras ; 20: e20200164, 2021. tab, graf
Article in Portuguese | LILACS | ID: biblio-1250241


Resumo Com o aumento da duração e frequência das viagens aéreas, observou-se um aumento da prevalência de tromboembolismo venoso nos passageiros. Este estudo avaliou a eficácia do uso de meias elásticas de compressão graduada para a prevenção de tromboembolismo venoso desencadeado por viagens aéreas com duração maior que 3 horas de voo. Trata-se de uma revisão sistemática de ensaios clínicos. A qualidade metodológica dos estudos e o nível de evidência científica foram avaliados pelo Consolidated Standards of Reporting Trials e Grading of Recommendations Assessment, Development and Evaluation. Foram identificados 34 artigos, entretanto apenas oito atenderam aos critérios de elegibilidade. Os desfechos incidência de tromboembolismo venoso e edema foram avaliados em 2.022 e 1.311 passageiros, respectivamente. Os estudos demonstraram evidências de alta qualidade para a prevenção de edema e de moderada qualidade para a redução da incidência de tromboembolismo venoso com o uso de meias elásticas de compressão graduada durante viagens aéreas.

Abstract The increase in duration and frequency of flights has led to an increase in the prevalence of venous thromboembolism among airline passengers. This study assesses the efficacy of graduated compression stockings for prevention of venous thromboembolism triggered by flights lasting more than 3 hours. The design is a systematic review of clinical trials. The methodological quality of studies and the level of scientific evidence were evaluated using the Consolidated Standards of Reporting Trials and Grading of Recommendations Assessment, Development and Evaluation standards. A total of 34 articles were identified, but only eight met the eligibility criteria. The outcomes incidence of venous thromboembolism and edema were assessed in 2,022 and 1,311 passengers, respectively. The studies presented high quality evidence demonstrating prevention of edema and moderate quality evidence of reduced incidence of venous thromboembolism associated with wearing graduated compression stockings during flights.

Humans , Male , Female , Adult , Middle Aged , Edema/prevention & control , Stockings, Compression , Venous Thromboembolism/prevention & control , Blood Flow Velocity , Lower Extremity , Air Travel
Chinese Journal of Cardiology ; (12): 1191-1197, 2021.
Article in Chinese | WPRIM | ID: wpr-941421


Objective: To explore the value of tissue Doppler imaging (TDI) combined with two-dimensional speckle tracking imaging (2D-STI) at rest on evaluating microcirculation dysfunction and left ventricular dysfunction in patients with angina and no obstructive coronary artery disease(ANOCA). Methods: This retrospective study recruited 78 ANOCA patients, who hospitalized in the People's Hospital of Liaoning Province from August 2019 to July 2021. These patients underwent conventional echocardiography examination, including TDI and 2D-STI, to evaluate the left ventricular dysfunction, and adenosine stress echocardiography (SE) to evaluate the coronary flow velocity reserve (CFVR). ANOCA patients were divided into coronary microcirculation dysfunction CMD group (CFVR<2) and control group (CFVR≥2) according to CFVR. Clinical data, routine echocardiographic parameters, TDI parameters including isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT), ejection time (ET), and STI parameters including global longitudinal peak strain (GLS), time to peak (TTP); peak strain dispersion (PSD) were compared between the two groups. Binary logistic regression was used to analyze the risk factors of CMD and the predictive value of each parameter to construct a joint prediction model for the diagnosis of CMD in this patient cohort. Results: The mean age was (55.5±11.2) years, 43 (55%) patients were females in this patient cohort, 38 (49%) patienst were didvided into the CMD group and 40 (51%) into the control group. Age, prevalence of hypertension, diabetes, dyslipidemia, and smokers were significantly higher in the CMD group than in the control group (all P<0.05). Tei index was higher, IVCT and TTP were longer, PSD was higher, ET was shorter, and absolute GLS was lower in the CMD group than in the control group (all P<0.05). The results of logistic regression analysis showed that longer IVCT, higher Tei index, higher time to PSD and lower absolute GLS were the independent risk factors of CMD. The ROC curve revealed that the predicting efficacy on CMD was satisfactiory with the combined predictors: AUC=0.884, sensitivity of 82% and specificity of 80%. Conclusions: TDI combined with 2D-STI is associated with a good diagnostic value on the diagnosis of CMD and left ventricular dysfunction in patients with ANOCA, which provides a feasible non-invasive tool for the diagnosis of CMD and risk stratification of patients with ANOCA.

Adult , Aged , Angina Pectoris , Blood Flow Velocity , Female , Humans , Microcirculation , Middle Aged , Retrospective Studies , Ventricular Dysfunction, Left/diagnostic imaging
Rev. bras. ginecol. obstet ; 42(10): 630-633, Oct. 2020. tab
Article in English | LILACS | ID: biblio-1144162


Abstract Objective Primary dysmenorrhea occurs due to abnormal levels of prostanoids, uterine contractions, and uterine blood flow. However, the reasons for pain in primary dysmenorrhea have not yet been clarified. We examined the blood flow alterations in patients with primary dysmenorrhea and determined the relationship between ischemia-modified albumin (IMA) levels, as an ischemia indicator, and primary dysmenorrhea. Methods In the present study, 37 patients who had primary dysmenorrhea and were in their luteal and menstrual phase of their menstrual cycles were included. Thirty individuals who had similar demographic characteristics, who were between 18 and 30 years old and did not have gynecologic disease were included as control individuals. Their uterine artery Doppler indices and serum IMA levels were measured. Results Menstrual phase plasma IMA levels were significantly higher than luteal phase IMA levels, both in the patient and in the control groups (p < 0.001). Although the menstrual phase IMA levels of patients were significantly higher than those of controls, luteal phase IMA levels were not significantly different between the two groups. Menstrual uterine artery pulsatility index (PI) and resistance index (RI) of primary dysmenorrhea patients were significantly different when compared with luteal uterine artery PI and RI levels. There was a positive correlation between menstrual phase IMA and uterine artery PI and RI in the primary dysmenorrhea. Conclusion Ischemia plays an important role in the etiology of the pain, which is frequently observed in patients with primary dysmenorrhea. Ischemia-modified albumin levels are considered as an efficient marker to determine the severity of pain and to indicate ischemia in primary dysmenorrhea.

Humans , Female , Arteries/physiology , Dysmenorrhea/physiopathology , Blood Flow Velocity , Pulsatile Flow , Biomarkers/blood , Cross-Sectional Studies , Ultrasonography, Doppler , Dysmenorrhea/blood , Serum Albumin, Human
Arq. bras. cardiol ; 115(3): 503-512, out. 2020. tab, graf
Article in English, Portuguese | LILACS, SES-SP | ID: biblio-1131314


Resumo Fundamento O grau de fluxo TIMI e a contagem quadro a quadro TIMI corrigida (CTFC) são métodos amplamente utilizados para avaliar o fluxo sanguíneo coronariano angiográfico. A medição do fluxo sanguíneo coronariano (FSC) na coronariografia (CAG) padrão despertou grande interesse recentemente, tentando combinar o conceito de CTFC com novos métodos para pós-angioplastia e avaliação da síndrome cardíaca X. Além disso, o fluxo coronariano lento é considerado um critério importante para a angina microvascular. Objetivo Explorar uma nova abordagem de medição angiográfica quantitativa do FSC com base na detecção densitométrica de contraste na CAG offline, usando um software acessível para obter uma avaliação mais precisa e confiável do FSC. Métodos Trinta pacientes foram estudados e divididos em 2 grupos: fluxo sanguíneo coronariano normal (FN) e fluxo sanguíneo coronariano lento (FL), de acordo com a definição da CTFC. O MD foi aplicado à amostra do estudo para diferenciar entre FN e FL. A estatística não paramétrica foi usada para avaliar diferenças entre os grupos com p<0,05. Resultados O valor de referência normal do MD obtido para o fluxo sanguíneo coronariano foi de 9 [5-10] quadros. Os grupos FN vs. FL foi comparado e expresso como mediana [intervalo interquartil], para a artéria descendente anterior esquerda: 10 [7-11] vs. 21 [8-33]; p=0,016; artéria circunflexa: 9 [4-13] vs. 14 [11-30]; p=0,012 e artéria coronária direita: 5 [3-11] vs. 13 [8-26]; p=0,009. Conclusão O MD mostrou a viabilidade de medir o fluxo sanguíneo coronariano com precisão, consistência e reprodutibilidade em um angiograma coronariano padrão, mostrando a capacidade adicional de diferenciar FN de FL em pacientes com dor precordial e artérias coronárias normais. (Arq Bras Cardiol. 2020; 115(3):503-512)

Abstract 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)

Humans , Microvascular Angina , Coronary Circulation , Blood Flow Velocity , Coronary Angiography , Hemodynamics
Arq. bras. oftalmol ; 83(5): 417-423, Sept.-Oct. 2020. tab, graf
Article in English | LILACS | ID: biblio-1131620


ABSTRACT Purposes: To evaluate changes in ocular blood flow and subfoveal choroidal thickness in patients with symptomatic carotid artery stenosis after carotid artery stenting. Methods: We included 15 men (mean age, 63.6 ± 9.1 years) with symptomatic carotid artery stenosis and 18 healthy volunteers (all men; mean age, 63.7 ± 5.3 years). All participants underwent detailed ophthalmologic examinations including choroidal thickness measurement using enhanced depth-imaging optic coherence tomography. The patients also underwent posterior ciliary artery blood flow measurements using color Doppler ultrasonography before and after carotid artery stenting. Results: Patients lacked ocular ischemic symptoms. Their peak systolic and end-diastolic velocities increased to 10.1 ± 13.1 (p=0.005) and 3.9 ± 6.3 (p=0.064) cm/s, respectively, after the procedure. Subfoveal choroidal thicknesses were significantly thinner in patients with carotid artery stenosis than those in the healthy controls (p=0.01). But during the first week post-procedure, the subfoveal choroidal thicknesses increased significantly (p=0.04). The peak systolic velocities of the posterior ciliary arteries increased significantly after carotid artery stenting (p=0.005). We found a significant negative correlation between the mean increase in peak systolic velocity values after treatment and the mean preprocedural subfoveal choroidal thickness in the study group (p=0.025, r=-0.617). Conclusions: In patients with carotid artery stenosis, the subfoveal choroid is thinner than that in healthy controls. The subfoveal choroidal thickness increases after carotid artery stenting. Carotid artery stenting treatment increases the blood flow to the posterior ciliary artery, and the preprocedural subfoveal choroidal thickness may be a good predictor of the postprocedural peak systolic velocity of the posterior ciliary artery.

RESUMO Objetivos: Avaliar alterações no fluxo sanguíneo ocular e na espessura da coroide subfoveal em pacientes com estenose sintomática da artéria carótida, após implante de stent nessa artéria. Métodos: Foram incluídos 15 homens (idade média de 63,6 ± 9,1 anos) com estenose sintomática da artéria carótida e 18 voluntários saudáveis (todos homens; idade média de 63,7 ± 5,3 anos). Todos os participantes foram submetidos a exames oftalmológicos detalhados, incluindo d medição da espessura da coroide, usando tomografia de coerência óptica com imagem de profundidade aprimorada. Os pacientes também foram submetidos a medidas do fluxo sanguíneo das artérias ciliares posteriores, usando ultrassonografia com Doppler colorido, antes e após o implante do stent na artéria carótida. Resultados: Os pacientes não apresentaram sintomas isquêmicos oculares. O pico de velocidade sistólica e diastólica final aumentou para 10,1 ± 13,1 (p=0,005) e 3,9 ± 6,3 (p=0,064) cm/s, respectivamente, após o procedimento. As espessuras da coroide subfoveais foram significativamente mais finas nos pacientes com estenose da artéria carótida do que nos controles saudáveis (p=0,01). Porém, durante a primeira semana pós-procedimento, as espessuras das coroides subfoveais aumentaram significativamente (p=0,04). O pico de velocidade sistólica das artérias ciliares posteriores aumentou significativamente após o stent na artéria carótida (p=0,005). Encontramos uma correlação negativa significativa entre o aumento médio dos valores máximos de velocidade sistólica após o tratamento e a espessura da coroide subfoveal pré-procedimento média no grupo de estudo (p=0,025, r=-0,617). Conclusões: Em pacientes com estenose da artéria carótida, a coroide subfoveal é mais fina que a dos controles saudáveis. A espessura da coroide subfoveal aumenta após o stent na artéria carótida. O tratamento com stent na artéria carótida aumenta o fluxo sanguíneo para a artéria ciliar posterior, e a espessura coroidal subfoveal pré-procedimento pode ser um bom preditor da velocidade sistólica de pico pós-procedimento da artéria ciliar posterior.

Humans , Male , Middle Aged , Aged , Ophthalmic Artery , Blood Flow Velocity , Carotid Arteries , Choroid , Regional Blood Flow , Stents , Choroid/anatomy & histology , Choroid/diagnostic imaging , Carotid Stenosis/surgery , Carotid Stenosis/diagnostic imaging , Tomography, Optical Coherence
Rev. bras. ginecol. obstet ; 42(5): 289-296, May 2020. graf
Article in English | LILACS | ID: biblio-1137828


Abstract Intrauterine growth restriction (IUGR) is associated with poor perinatal prognosis and a higher risk of stillbirth, neonatal death, and cerebral palsy. Its detection and the evaluation of its severity by new Doppler velocimetric parameters, such as aortic isthmus (AoI), are of great relevance for obstetrical practice. The AoI is a vascular segment that represents a point of communication between the right and left fetal circulations. It is considered to be a functional arterial shunt that reflects the relationship between the systemic and cerebral impedances, and has recently been proposed as a tool to detect the status of hemodynamic balance and prognosis of IUGR in fetuses. In the present review, we noticed that in healthy fetuses, the AoI net flow is always antegrade, but in fetuses with IUGR the deterioration of placental function leads to progressive reduction in its flow until it becomes mostly retrograde; this point is associated with a drastic reduction in oxygen delivery to the brain. The more impaired the AoI flow is, the greater is the risk of impairment in the Doppler velocimetry of other vessels; and the alterations of the AoI Doppler seem to precede other indicators of severe hypoxemia. Although there seems to be an association between the presence of retrograde flow in the AoI and the risk of long-term neurologic disability, its role in the prediction of perinatal morbi-mortality remains unclear. The AoI Doppler seems to be a promising tool in the management of fetuses with IUGR, but more studies are needed to investigate its employment in clinical practice.

Resumo O crescimento intrauterino restrito (CIUR) está associado a um prognóstico perinatal adverso, com maior risco de óbito intrauterino e neonatal, bem como de paralisia cerebral. Assim, sua detecção e a determinação de sua gravidade por novos parâmetros Dopplervelocimétricos, como o istmo aórtico (IAo), são de fundamental importância na prática obstétrica. O IAo é um segmento vascular que representa um ponto de comunicação entre os sistemas circulatórios fetais esquerdo e direito. É considerado um shunt arterial funcional, capaz de refletir a relação entre as impedâncias dos circuitos cerebral e sistêmico, e foi proposto como uma ferramenta para detecção do status do equilíbrio hemodinâmico e do prognóstico de fetos com CIUR. Na presente revisão, observou-se que, em fetos saudáveis, o fluxo predominante no IAo é sempre anterógrado; mas em fetos com CIUR a deterioração do estágio de insuficiência placentária acarreta reduções progressivas no fluxo ístmico até este apresentar sentido predominantemente retrógrado e levar a uma drástica redução no aporte de oxigênio ao sistema nervoso central. Quanto mais alterado estiver o fluxo no IAo, maior a chance de haver alteração na Dopplervelocimetria de outros vasos; e as alterações no Doppler do IAo parecem preceder outros indicadores de hipoxemia severa. Embora o fluxo retrógrado no IAo pareça se correlacionar com maior risco de alteração no desenvolvimento neurológico a longo prazo, ainda não está claro o seu papel na predição de morbimortalidade perinatal. O Doppler do IAo parece ser um parâmetro promissor no manejo do CIUR; entretanto, mais estudos são necessários para avaliar seu emprego na prática clínica.

Humans , Female , Pregnancy , Infant, Newborn , Aorta, Thoracic/diagnostic imaging , Ultrasonography, Prenatal , Fetal Growth Retardation/diagnostic imaging , Fetus/diagnostic imaging , Aorta, Thoracic/physiopathology , Blood Flow Velocity , Ultrasonography, Doppler , Fetal Growth Retardation/physiopathology , Fetus/blood supply
Clinics ; 75: e1212, 2020. tab, graf
Article in English | LILACS | ID: biblio-1055876


OBJECTIVE: To evaluate the findings of magnetic resonance angiography (MRA) and transcranial Doppler ultrasound (TCD) in patients with a clinical diagnosis of vertebrobasilar insufficiency (VBI). METHOD: From our outpatient neurotology clinic, we selected patients (using the criteria proposed by Grad and Baloh) with a clinical diagnosis of VBI. We excluded patients with any definite cause for vestibular symptoms, a noncontrolled metabolic disease or any contraindication to MRA or TCD. The patients in the study group were sex- and age-matched with subjects who did not have vestibular symptoms (control group). Our final group of patients included 24 patients (study, n=12; control, n=12). RESULTS: The MRA results did not demonstrate significant differences in the findings between our study and control groups. TCD demonstrated that the systolic pulse velocity of the right middle cerebral artery, end diastolic velocity of the basilar artery, pulsatility index (PI) of the left middle cerebral artery, PI of the right middle cerebral artery, and PI of the basilar artery were significantly higher in the study group than in the control group, suggesting abnormalities affecting the microcirculation of patients with a clinical diagnosis of VBI compared with controls. CONCLUSION: MRA failed to reveal abnormalities in patients with a clinical diagnosis of VBI compared with controls. The PI of the basilar artery, measured using TCD, demonstrated high sensitivity (91%) and specificity (91%) for detecting clinically diagnosed VBI.

Humans , Basilar Artery/diagnostic imaging , Vertebrobasilar Insufficiency/diagnostic imaging , Ultrasonography, Doppler, Transcranial/methods , Magnetic Resonance Angiography , Blood Flow Velocity , Microcirculation
Article in Chinese | WPRIM | ID: wpr-828198


This paper describes how to develop a practical new type of atherosclerosis detection device, which can realize real-time measurement and analysis of human atherosclerosis. According to the mechanism of human atherosclerosis, the design objectives of the system are formulated to determine the construction of the platform. The system calculates the pulse wave velocity by measuring the pulse wave of human fingers and toes, adds four blood pressure measurements to the system design, calculates the ankle-brachial index, and comprehensively measures and analyses the degree of human arteriosclerosis.

Ankle , Atherosclerosis , Blood Flow Velocity , Blood Pressure , Brachial Artery , Humans , Pulse Wave Analysis
Article in Chinese | WPRIM | ID: wpr-942695


The study comprehensively puts forward several detection methods to arteriosclerosis and mainly discusses the method for pulse wave velocity (PWV for short) and ankle brachial index (ABI for short). On the basis of methods mentioned above, a portable system device for arteriosclerosis detection based on non-invasive PWV and limb blood pressure is introduced, and expectations for the subsequent engineering design and development direction are given for reference.

Ankle , Arteriosclerosis/diagnosis , Blood Flow Velocity , Blood Pressure , Brachial Artery , Humans , Pulse Wave Analysis
Arq. bras. cardiol ; 113(6): 1072-1081, Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1055073


Abstract Background: Arterial compliance reduction has been associated with aging and hypertension in supine position. However, the dynamic effects of orthostatism on aortic distensibility has not been defined. Objective: We sought to determine the orthostatic influence and the interference of age, blood pressure (BP) and heart rate (HR) on the great arteries during gravitational stress. Methods: Ninety-three healthy volunteers (age 42 ± 16 years). Carotid-femoral pulse wave velocity (PWV) assumed as aortic stiffness was assessed in supine position (basal phase), during tilt test (TT) (orthostatic phase) and after return to supine position (recovery phase). Simultaneously with PWV acquisition, measures of BP and HR rate were recorded. Results: PWV during TT increased significantly compared to the basal and recovery phases (11.7 ± 2.5 m/s vs. 10.1 ± 2.3 m/s and 9.5 ± 2.0 m/s). Systolic BP (r = 0.55, r = 0.46 and r = 0.39) and age (r = 0.59, r = 0.63 and r = 0.39) correlated with PWV in all phases. The significance level for all tests was established as α = 0.05. Conclusion: We conclude that there is a permanent increase in PWV during orthostatic position that was returned to basal level at the recovery phase. This dynamic pattern of PWV response, during postural changes, can be explained by an increase in hydrostatic pressure at the level of abdominal aorta which with smaller radius and an increased elastic modulus, propagates the pulse in a faster way. Considering that it could increase central pulse reflection during the orthostatic position, we speculate that this mechanism may play a role in the overall adaptation of humans to gravitational stress.

Resumo Fundamento: A redução da complacência arterial tem sido associada ao envelhecimento e à hipertensão na postura supina. Entretanto, os efeitos dinâmicos do ortostatismo na distensibilidade aórtica não foram definidos. Objetivo: Determinar a influência ortostática e a interferência da idade, pressão arterial (PA) e frequência cardíaca (FC) sobre as grandes artérias durante o estresse gravitacional. Métodos: Noventa e três voluntários saudáveis (idade de 42 ± 16 anos). A velocidade da onda de pulso carotídeo-femoral (VOP), assumida como rigidez aórtica, foi avaliada na posição supina (fase basal) durante o teste de inclinação (TT) (fase ortostática) e após o retorno à posição supina (fase de recuperação). Simultaneamente à aquisição da PWV, registrou-se as medidas de PA e FC. Resultados: A VOP durante o TT aumentou significativamente em comparação com as fases basal e de recuperação (11,7 ± 2,5 m/s vs. 10,1 ± 2,3 m/se 9,5 ± 2,0 m/s). PA sistólica (r = 0,55, r = 0,46 e r = 0,39) e idade (r = 0,59, r = 0,63 e r = 0,39) correlacionaram-se com a VOP em todas as fases. O nível de significância para todos os testes foi estabelecido como = 0,05. Conclusão: Observou-se um aumento permanente da VOP durante a postura ortostática, que retornou ao nível basal na fase de recuperação. Esse padrão dinâmico de resposta da VOP, durante as alterações posturais, pode ser explicado pelo aumento da pressão hidrostática no nível da aorta abdominal que, com raio menor e aumento do módulo de elasticidade, propaga o pulso de maneira mais rápida. Considerando-se que poderia aumentar a reflexão do pulso central durante a posição ortostática, podemos especular que esse mecanismo pode desempenhar um papel na adaptação global do humano ao estresse gravitacional.

Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Young Adult , Arteries/physiology , Baroreflex/physiology , Vascular Stiffness/physiology , Pulse Wave Analysis , Heart Rate/physiology , Hypotension, Orthostatic , Posture , Stress, Physiological , Blood Flow Velocity , Adaptation, Physiological , Cardiovascular Physiological Phenomena , Body Mass Index , Gravitation
Arch. endocrinol. metab. (Online) ; 63(5): 495-500, Sept.-Oct. 2019. tab
Article in English | LILACS | ID: biblio-1038504


ABSTRACT 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.

Humans , Male , Female , Adult , Middle Aged , Thyroid Gland/diagnostic imaging , Thyroiditis/diagnostic imaging , Graves Disease/diagnostic imaging , Thyroid Gland/blood supply , Blood Flow Velocity , Sensitivity and Specificity , Sodium Pertechnetate Tc 99m , Diagnosis, Differential