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1.
Sci Rep ; 14(1): 23144, 2024 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367038

RESUMO

Computational models can be at the basis of new powerful technologies for studying and classifying disorders like pre-eclampsia, where it is difficult to distinguish pre-eclamptic patients from non-pre-eclamptic based on pressure when patients have a track record of hypertension. Computational models now enable a detailed analysis of how pregnancy affects the cardiovascular system. Therefore, new non-invasive biomarkers were developed that can aid the classification of pre-eclampsia through the integration of six different measured non-invasive cardiovascular signals. Datasets of 21 pregnant women (no early onset pre-eclampsia, n = 12; early onset pre-eclampsia, n = 9) were used to create personalised cardiovascular models through computational modelling resulting in predictions of blood pressure and flow waveforms in all major and minor vessels of the utero-ovarian system. The analysis performed revealed that the new predictors PPI (pressure pulsatility index) and RI (resistance index) calculated in arcuate and radial/spiral arteries are able to differentiate between the 2 groups of women (t-test scores of p < .001) better than PI (pulsatility index) and RI (Doppler calculated in the uterine artery) for both supervised and unsupervised classification. In conclusion, two novel high-performing biomarkers for the classification of pre-eclampsia have been identified based on blood velocity and pressure predictions in the smaller placental vasculatures where non-invasive measurements are not feasible.


Assuntos
Biomarcadores , Pré-Eclâmpsia , Humanos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/fisiopatologia , Feminino , Gravidez , Adulto , Modelos Cardiovasculares , Pressão Sanguínea , Velocidade do Fluxo Sanguíneo
2.
Sci Rep ; 14(1): 23151, 2024 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-39367200

RESUMO

Pulsatile hemodynamics have been shown to be independent predictors of cardiovascular events. The aim of the current study was to describe four pulsatile hemodynamic markers in a large, well-established, population-based cohort and to provide reference equations for sex- and age-based standardization of these measurements. 6828 adult participants from the Austrian LEAD (Lung, hEart, sociAl, boDy) cohort study, who were free from overt cardiovascular disease, non-diabetic based on blood test results, and had no history of pharmacological treatment for hypertension, dyslipidemia, and diabetes, comprised the "reference population". Carotid-femoral pulse wave velocity (cfPWV), augmentation index (AIx), amplitude of forward wave (Pf), and backward wave (Pb) were described in different age categories for both sexes. Sex-specific reference equations for cfPWV, AIx, Pf, and Pb with age as the predictive variable were created using the Lambda-Mu-Sigma (LMS) method. All four parameters increased with age. CfPWV and Pf were higher in males than females, especially in young and middle-age groups (P < 0.001). AIx was higher in females than males in all age categories (P < 0.001). Pb was also higher in females than males in age groups older than 40 years (P < 0.01). Reference equations for the skewness (Lambda), median (Mu), and coefficient of variation (Sigma) values were determined, enabling the calculation of sex- and age-standardized values (z-scores) for each individual's pulsatile hemodynamic measurement, and an online application was developed. Reference equations derived from a large population-based dataset constitute a suitable tool for the standardization of pulsatile hemodynamics and for the accurate interpretation of vascular aging.


Assuntos
Análise de Onda de Pulso , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Análise de Onda de Pulso/métodos , Idoso , Valores de Referência , Adulto Jovem , Estudos de Coortes , Hemodinâmica/fisiologia , Rigidez Vascular/fisiologia
3.
Physiol Rep ; 12(19): e70036, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39362825

RESUMO

The age-related loss of muscle mass is partly accounted for by the loss of sarcomeres in series, contributing to declines in muscle mechanical performance. Resistance training biased to eccentric contractions increases serial sarcomere number (SSN) in young muscle, however, maximal eccentric training in old rats previously did not alter SSN and worsened performance. A submaximal eccentric training stimulus may be more conducive to adaptation for aged muscle. The purpose of this study was to assess whether submaximal eccentric training can increase SSN and improve mechanical function in old rats. Twelve 32-month-old male F344/BN rats completed 4 weeks of submaximal (60% maximum) eccentric plantar-flexion training 3 days/week. Pre- and post-training, we assessed in-vivo maximum isometric torque at a stretched and neutral ankle angle, the passive torque-angle relationship, and the isotonic torque-velocity-power relationship. The soleus and medial gastrocnemius (MG) were harvested for SSN measurements via laser diffraction, with the untrained leg as a control. SSN increased 11% and 8% in the soleus and MG, respectively. Training also shifted optimal torque production towards longer muscle lengths, reduced passive torque 42%, and increased peak isotonic power 23%. Submaximal eccentric training was beneficial for aged muscle adaptations, increasing SSN, reducing muscle passive tension, and improving dynamic contractile performance.


Assuntos
Músculo Esquelético , Condicionamento Físico Animal , Ratos Endogâmicos F344 , Treinamento Resistido , Sarcômeros , Animais , Masculino , Músculo Esquelético/fisiologia , Sarcômeros/fisiologia , Ratos , Condicionamento Físico Animal/fisiologia , Condicionamento Físico Animal/métodos , Treinamento Resistido/métodos , Envelhecimento/fisiologia , Torque , Contração Muscular/fisiologia , Ratos Endogâmicos BN , Contração Isométrica/fisiologia , Força Muscular/fisiologia
4.
J Environ Manage ; 370: 122805, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39366220

RESUMO

Optimizing the dosage of coagulant is a time-consuming process, and real-time evaluation of floc settling velocity can quickly predict the coagulation effect and optimize the dosage. This study used a convolutional neural network (CNN) model to analyze the accuracy of floc image recognition of settling velocity. Python-OpenCV was employed to develop a program that segments individual flocs and detects their settling velocity to constructing a dataset of floc images and settling velocity. The results showed that the accuracy of determining the settling velocity of flocs solely based on their particle size was 88%, indicating that the floc structure is complex and a single parameter is not sufficient to accurately identify settling velocity. The results of the CNN analysis indicated that using a relatively simple Lenet5 structure can quickly achieve an accuracy of 88%, while using a Resnet18 structure can achieve recognition accuracy of over 90%. These findings suggest that machine learning techniques applied to floc images can effectively evaluate floc settling velocity, providing theoretical guidance for optimizing coagulant dosage and regulating coagulation processes.

5.
J Diabetes Complications ; 38(11): 108877, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39366315

RESUMO

Youths with type 1 diabetes (T1D) exhibits higher levels of pulse wave velocity (PWV) compared to healthy controls. Higher PWV in T1D subjects is associated with increased hazard of progression in albuminuria, decline in eGFR, cardiovascular (CV) events and mortality. In the recently published work by Georeli et al., increased PWV was associated with poor glycemic control as expressed by time-in-range (TIR) < 50 % in T1D children, adolescents and young adults. This finding is of great interest, since it is well known that glycemic control, as measured by TIR, is an important contributor of CV risk. The duration of TIR < 50 % is not reported by the authors, but is of importance, knowing that CGM provide data for the last 3-6 months, depending on the CGM model. In conclusion, PWV looks promising for risk stratification in T1D, but its exact role in T1D still remains to be fully explored.

6.
Front Cardiovasc Med ; 11: 1468379, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39364064

RESUMO

Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia, significantly increasing the risk of death and stroke. The left atrial appendage (LAA) plays a crucial role in the development of AF. Reduced left atrial appendage emptying velocity (LAAEV) is an important indicator of nonvalvular AF, associated with thrombosis and recurrence after catheter ablation. This study aims to identify factors influencing LAAEV and construct a predictive model for LAAEV in nonvalvular AF patients. Methods: This retrospective cohort study included 1,048 nonvalvular AF patients hospitalized at the Second Hospital of Hebei Medical University from January 1, 2015, to December 31, 2021. Patients underwent transthoracic and transesophageal echocardiography and had complete laboratory data. Statistical analyses included binary logistic regression and multiple linear regression to identify independent predictors of reduced LAAEV and construct a predictive model. Results: Patients were divided into two groups: reduced LAAEV (<40 cm/s) and normal LAAEV (≥40 cm/s). The reduced LAAEV group included 457 patients (43.61%), with significant differences in age, gender, alcohol consumption, heart failure (HF), ischemic stroke, AF type, resting heart rate, CHA2DS2-VASc score, serum creatinine (SCR), serum uric acid (SUA), estimated glomerular filtration rate (eGFR), glycated hemoglobin (HbA1C), ß2 macroglobulin (B2M), left atrial diameter (LAD), and left ventricular ejection fraction (LVEF) compared to the normal LAAEV group. Logistic regression analysis identified age (OR 0.974, 95% CI 0.951-0.997, P = 0.028), HF (OR 0.637, 95% CI 0.427-0.949, P = 0.027), AF type [Persistent AF vs. PAF (OR 0.063, 95% CI 0.041-0.095, P = 0) Long-standing Persistent AF vs. PAF (OR 0.077, 95% CI 0.043-0.139, P = 0)], LAD (OR 0.872, 95% CI 0.836-0.91, P < 0.001), and LVEF (OR 1.057, 95% CI 1.027-1.089, P = 0) as independent predictors of reduced LAAEV. Multiple linear regression analysis included age, AF type, LAD, and LVEF in the final predictive model, explaining 43.5% of the variance in LAAEV (adjusted R² = 0.435). Conclusion: Age, HF, type of AF, LAD, and LVEF are independent predictors of reduced LAAEV. The predictive model (LAAEV = 96.567-15.940 × AFtype-1.309 × LAD-0.18 × Age + 37.069 × LVEF) demonstrates good predictive value, aiding in the initial assessment and management of nonvalvular AF patients.

7.
J ISAKOS ; : 100332, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39362603

RESUMO

Bilateral low-velocity multi-ligament knee Injury (MLKI) is a rare injury increasing in prevalence along with obesity. Early surgical intervention is indicated to improve long-term outcomes. We describe the surgical and postoperative management of a bilateral MLKI. The patient underwent staged multi-ligament knee reconstruction 17 and 35 days after injury. Return to light-duty was achieved 4 weeks following each procedure and progression to exercise at 6 months. The patient is 2 year postoperative and returned to all activity without complaint. We describe successful surgical and rehabilitation management, which encourages early surgery and rehabilitation strategies to improve long-term outcomes.

8.
J Ultrasound Med ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39360549

RESUMO

OBJECTIVES: Myofascial trigger points (MTrPs) are potential contributors to shoulder pain and can lead to local ischemia and hypoxia, thus causing pain. Color Doppler ultrasound (US) has been used to examine the vascular environment around MTrPs, but has not been used to examine blood flow impairments in patients with shoulder pain and MTrPs. The reliability of color Doppler US for measuring infraspinatus muscle blood flow also has not been established. This study aimed to investigate differences in blood flow between individuals with and without shoulder pain and the reliability of Doppler US for measuring infraspinatus muscle blood flow. METHODS: Forty participants were enrolled, 20 with shoulder pain and MTrPs and 20 without. Color Doppler US examination was performed twice on each participant to measure peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI), and pulsatile index (PI) of the infraspinatus muscle. RESULTS: The symptomatic participants had significantly higher PSV (ie, impaired blood flow) than the asymptomatic participants. There were no significant between-group differences in EDV, RI, and PI. The results also demonstrated good-to-excellent intra-rater reliability for color Doppler US measurements of PSV, EDV, RI, and PI for both groups. CONCLUSION: This study demonstrated differences in blood flow near MTrPs in the infraspinatus muscle between individuals with and without shoulder pain. It also established good-to-excellent reliability of color Doppler US in measuring infraspinatus muscle blood flow. These findings suggest color Doppler US is a useful tool to identify vascular impairments for shoulder pain associated with MTrPs.

9.
Artigo em Inglês | MEDLINE | ID: mdl-39365212

RESUMO

BACKGROUND: Atrial conduction velocity (CV) is influenced by autonomic tone and contributes to the pathophysiology of re-entrant arrhythmias and atrial fibrillation. Cardiac sympathetic nerve activation has been reported via electrical stimulation within the vertebral vein (VV). OBJECTIVES: This study sought to characterize changes in right atrial (RA) CV associated with sympathetic stimulation from pharmacologic (isoproterenol) or direct electrical (VV stimulation) approaches. METHODS: Subjects undergoing catheter ablation for atrial fibrillation had baseline RA electroanatomic maps performed in sinus rhythm (SR). RA mapping was repeated during right VV stimulation (20 Hz; up to 20 mA) and again with both RA pacing and during isoproterenol infusion, each titrated to the heart rate achieved with VV stimulation. RESULTS: A total of 100 RA maps were analyzed from 25 subjects (mean age: 58 ± 14 years; 56% male), and CV was calculated from 51,534 electroanatomic map points. VV stimulation increased heart rate from baseline in all subjects (22.5 ± 5.5 beats/min). The average CV increased with VV stimulation (82.0 ± 34.5 cm/s) or isoproterenol (83.7 ± 35.0 cm/s) when compared to SR (70.8 ± 32.5 cm/s; P < 0.001). Heterogeneity of CV decreased with VV stimulation or isoproterenol when compared to SR (coefficient of variation: 0.33 ± 0.21 vs 0.35 ± 0.23 vs 0.57 ± 0.29; P < 0.001). There was no difference in CV or CV heterogeneity between SR and RA pacing, suggesting that these changes were independent of heart rate. CONCLUSIONS: Global RA CV is enhanced, and heterogeneity of CV is reduced, with either pharmacologic or direct electrical sympathetic stimulation via the right VV.

10.
BMC Cardiovasc Disord ; 24(1): 529, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354384

RESUMO

OBJECTIVE: In the present study, we aimed to explore the association between left atrial appendage emptying velocity (LAAEV) measured by transesophageal echocardiography and atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA) in patients with early persistent atrial fibrillation (PeAF). METHODS: We retrospectively analyzed patients with early PeAF who underwent their initial ablation procedure. The echocardiographic and clinical data of the enrolled patients were collected and recorded prior to the operation. Following adjustment for confounding factors, we investigated the relationship between the LAAEV and AF recurrence in patients with early PeAF after radiofrequency ablation. RESULTS: The proportions of AF recurrence in the low, medium, and high LAAEV groups were 48.8%, 16.0%, and 13.1%, respectively. After adjusting for potential confounding factors, we observed a gradual decrease in the risk of AF recurrence with increasing LAAEV (odds ratio: 0.882, 95% confidence interval: 0.842-0.924, p<0.001). This trend was statistically significant (p<0.001), particularly when comparing the high and low LAAEV groups (odds ratio: 0.033, 95% confidence interval: 0.009-0.116, p<0.001). Curve fitting analysis demonstrated an approximate negative linear association between LAAEV and the probability of AF recurrence. CONCLUSIONS: Among patients with early PeAF who successfully underwent their first RFCA, we found that the LAAEV within 24 h before the procedure was independently correlated with the risk of AF recurrence. Notably, this association was negative, indicating that higher LAAEV was associated with a lower risk of AF recurrence.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Função do Átrio Esquerdo , Ablação por Cateter , Ecocardiografia Transesofagiana , Recidiva , Humanos , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/diagnóstico por imagem , Apêndice Atrial/fisiopatologia , Apêndice Atrial/diagnóstico por imagem , Masculino , Feminino , Ablação por Cateter/efeitos adversos , Estudos Retrospectivos , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento , Fatores de Tempo , Idoso , Frequência Cardíaca , Medição de Risco , Valor Preditivo dos Testes
11.
World J Nephrol ; 13(3): 95262, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39351188

RESUMO

BACKGROUND: Flavonoids, the main class of polyphenols, exhibit antioxidant and antihypertensive properties. AIM: To prospectively investigate the impact of flavonoids on arterial stiffness in patients with chronic kidney disease (CKD) stages I-IV. METHODS: In this prospective, single-arm study, CKD patients with arterial hypertension and diabetes mellitus were enrolled. Baseline demographic, clinical, and laboratory variables were recorded. Patients received daily treatment with a phenol-rich dietary supplement for 3 months. Blood pressure, arterial stiffness (carotid-femoral pulse wave velocity, central pulse pressure), and oxidative stress markers (protein carbonyls, total phenolic compound, total antioxidant capacity) were measured at baseline and at study end. RESULTS: Sixteen patients (mean age: 62.5 years, 87.5% male) completed the study. Following intervention, peripheral systolic blood pressure decreased significantly by 14 mmHg (P < 0.001). Carotid-femoral pulse wave velocity decreased from 8.9 m/s (baseline) to 8.2 m/s (study end) (P < 0.001), and central pulse pressure improved from 59 mmHg to 48 mmHg (P = 0.003). Flavonoids also reduced oxidative stress markers including protein carbonyls (P < 0.001), total phenolic compound (P = 0.001), and total antioxidant capacity (P = 0.013). CONCLUSION: Flavonoid supplementation in CKD patients shows promise in improving blood pressure, arterial stiffness, and oxidative stress markers.

12.
Front Aging Neurosci ; 16: 1457675, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39355539

RESUMO

Background: The mechanism of cognitive impairment in hemodialysis patients is multifactorial. The relationship between cerebral blood flow and the decline of cognitive function is poorly understood. Objective: To investigate the association between cerebral blood flow variation and decline of cognitive function in older patients undergoing hemodialysis. Methods: In this prospective observational cohort study of 121 older patients undergoing hemodialysis, we used transcranial Doppler ultrasound (TCD) to measure cerebral arterial mean flow velocity (MFV) throughout dialysis, assessed cognitive function at baseline and 12-month follow-up, and then analyzed associations between MFV and changes on cognitive scores. Results: TCD recordings demonstrated a significant reduction in MFV throughout dialysis, which were significantly correlated with cumulative ultrafiltration volume (rho 0.356, p < 0.001), ΔSBP (rho 0.251, p = 0.005), and ΔMAP (rho 0.194, p = 0.032). Compared with the baseline assessments, cognitive scores of participants at the 12-month follow-up were significantly worsened in global cognition (MOCA), some tests of memory (CFT-memory), executive function (TMT-B, SCWT-C, and SCWT-T), attention/processing speed (SDMT), and visuospatial function (CFT-copy) (p < 0.05). The worsening scores in global cognition (MOCA) (ß = 0.066, 95% CI 0.018-0.113, p = 0.007) and some tests of memory (AVLT5) (ß = 0.050, 95% CI 0.004-0.097, p = 0.035) and executive function (TMT-B, SCWT-C, SCWT-T) (ß = 1.955, 95% CI 0.457-3.453, p = 0.011; ß = 0.298, 95% CI 0.112-0.484, p = 0.002 and ß = 1.371, 95% CI 0.429-2.303, p = 0.004, respectively) were significantly associated with the reduction of MFV. Conclusion: Hemodialysis may significantly reduce cerebral blood flow in older patients; Repetitive intradialytic decreases in CBF may be one of the mechanisms underlying the decline of cognitive function. Clinical trial registration: https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000C5B5&selectaction=Edit&uid=U0003QEL&ts=4&cx=-djoi2.

13.
Rev Cardiovasc Med ; 25(9): 339, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39355589

RESUMO

Background: To explore aortic stiffness measured by carotid femoral-pulse wave velocity (cf-PWV) at different stages of normal glucose, prediabetes, and diabetes mellitus (DM). Methods: The literature comparing aortic stiffness (AS) with cf-PWV between DM and non-DM samples was systematically retrieved from Pubmed, Ovid Medline, Web of Science, Embase, Scopus, CNKI, and Wanfang databases. The Newcastle-Ottawa Scale was used to assess the quality of the literature. The primary endpoint was the mean difference (MD) of cf-PWV between the normal glucose and DM samples and normal glucose and prediabetes samples. The secondary endpoints were the MD of carotid intima-media thickness (cIMT) and carotid-radial pulse wave velocity (cr-PWV). Aggregated MD and 95% confidence intervals were calculated. When the I2 value was >50% or p < 0.01, the heterogeneity was considered large, and the random-effect model was used; otherwise, the fixed-effect model was used. A sensitivity analysis was conducted to identify the source of heterogeneity, and a funnel plot and the regression Egger test was utilized to assess the publication bias. Results: A total of 37 studies were finally enrolled. Samples with DM had a higher cf-PWV value and cIMT value than those without DM, and the differences were statistically significant. The cr-PWV measurements tended to be higher in the DM group than in the non-DM group, but the difference was not significant. Samples with prediabetes also had a significantly higher cf-PWV value than samples with normal glucose. Conclusions: Samples with DM and prediabetes were associated with a higher cf-PWV value, indicating that DM patients had a higher central AS. Central AS progresses at the prediabetes stage. These data provide insight into understanding the mechanism of adverse effects of DM and prediabetes on artery stiffness.

14.
J Undergrad Neurosci Educ ; 22(3): A207-A216, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39355677

RESUMO

Stringent animal welfare principles are forcing undergraduate instructors to avoid the use of animals. Therefore, many hands-on lab sessions using laboratory animals are progressively replaced by computer simulations. These versatile software simulations permit the observation of the behavior of biological systems under a great variety of experimental conditions. While this versatility is important, computer simulations often work even when a student makes wrong assumptions, a situation that poses its own pedagogical problem. Hands-on learning provides pupils with the opportunity to safely make mistakes and learn organically through trial and error and should therefore still be promoted. We propose an electronic model of an excitable cell composed of different modules representing different parts of a neuron - dendrites, soma, axon and node of Ranvier. We describe a series of experiments that allow students to better understand differences between passive and active cell responses and differences between myelinated and demyelinated axons. These circuits can also be used to demonstrate temporal and spatial summation of signals coming to the neuron via dendrites, as well as the neuron coding by firing frequency. Finally, they permit experimental determination along with theoretical calculations of important biophysical properties of excitable cells, such as rheobase, chronaxie and space constant. This open-source model has been successfully integrated into an undergraduate course of the physiology of excitable cells and student feedback assessment reveals that it helped students to understand important notions of the course. Thus, this neuromorphic circuit could be a valuable tool for biophysics and neuroscience courses in other universities.

15.
J Sports Sci ; : 1-9, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356873

RESUMO

The prediction of one-repetition maximum (1RM) using the submaximal load-velocity relationship (LVR) is highly relevant for the field of strength and conditioning. The optimal minimum velocity threshold (MVT) was recently proposed to increase the accuracy of 1RM predictions. However, using the average optimal MVT would allow for more practical estimations. LVRs of the free-weight back squat were obtained in 53 participants, throughout 2 sessions. LVRs were obtained using the multi- and two-point methods. Estimations of 1RM were made based on the average actual MVT (1RM velocity) and the average optimal MVT. The accuracy of 1RM predictions was examined using absolute-percent error and Bland-Altman plots. Cross-validation was performed using a leave-one-out approach. The number of selected loads did not affect the slope, y-intercept, optimal MVT or the accuracy of 1RM predictions. Predictions based on the average optimal MVT displayed greater accuracy than those obtained with the average actual MVT (~6% vs. ~8% absolute-percent error, respectively). However, wide 95% limits of agreement (LoA) were found between actual and estimated 1RM using both approaches (~13%1RM). The average optimal MVT offers more accurate 1RM estimations than the average actual MVT. However, errors prove substantial, making it challenging to precisely track minor changes in 1RM.

16.
Artigo em Inglês | MEDLINE | ID: mdl-39363522

RESUMO

OBJECTIVE: To compare maternal vascular indices and hemodynamic parameters at 35-37 weeks' gestation in pregnancies complicated by gestational diabetes mellitus (GDM), those with pre-existing diabetes mellitus (DM) and those without GDM or pre-existing DM. METHODS: This was a prospective observational study in women with a singleton pregnancy attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. The visit included recording of maternal demographic characteristics and medical history, and measurement of vascular indices and hemodynamic parameters using a non-invasive operator-independent device. These included carotid-to-femoral pulse-wave velocity, augmentation index, cardiac output, stroke volume, central systolic and diastolic blood pressure, total peripheral resistance and heart rate. The values in the GDM and pre-existing DM groups were compared to those in the unaffected group. RESULTS: We examined 6746 women, of whom 396 were excluded because they had chronic hypertension or developed pre-eclampsia or gestational hypertension. The study population of 6350 pregnancies contained 99 (1.6%) with pre-existing Type-I or Type-II DM and 617 (9.7%) that developed GDM, including 261 (42.3%) that were treated with diet alone, 239 (38.7%) treated with metformin alone and 117 (19.0%) treated with insulin with or without metformin. Among women with GDM and those with pre-existing DM, compared to those without GDM or pre-existing DM, there was a higher median cardiac output and heart rate, central systolic and diastolic blood pressure and pulse-wave velocity, but there was no significant difference in stroke volume and total peripheral resistance. There were no significant differences within the GDM group according to treatment type, except for higher heart rate in women treated with metformin alone compared to the group treated with diet alone. CONCLUSION: Women with GDM and those with pre-existing DM have evidence of early vascular disease in the third trimester, and this may contribute to their increased long-term cardiovascular risk. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

17.
Heart Rhythm ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39370027

RESUMO

BACKGROUND: Atrial fibrillation (AF) leads to impaired left atrial appendage contractility, increasing the risk of thromboembolic stroke. The left atrial appendage emptying velocity (LAAev) measured on transesophageal echocardiogram (TEE) is a marker of increased thromboembolic risk. OBJECTIVES: To evaluate predictors of reduced LAAev for identifying individuals at increased risk of cardiogenic stroke. METHODS: This was a single-center retrospective review of TEEs and clinical charts. Predictors of LAAev <30 cm/s were identified using logistic regression. A risk prediction model was created using stepwise selection in a derivation set (n=695) and separately tested in a validated set (n=300). RESULTS: We included TEEs on 995 patients (age 71.3±12.7 years, female 38.1%, history of AF 82.1%, in AF at evaluation 27.7%, CHA2DS2-VASc score 4.1±1.9, LAAev 41.6±21.0 cm/s). Significant multivariable predictors of LAAev <30 cm/s in derivation set were used to create the CHIRP3M-1 score containing 8 variables: Coronary artery disease (1), congestive Heart failure (1), Increased left atrial volume index ≥42 mL/m2 (1), current Rhythm AF (1), Paroxysmal AF (2), Persistent AF (3), long standing Persistent/permanent AF (4), and >moderate Mitral regurgitation (-1). In the validation set, as compared to intermediate scores (3-4), those with a low scores (≤2) and high scores (≥5) had odds ratios for LAAev <30 cm/s of 0.41 (0.21, 0.78, p=0.007) and 2.58 (95% CI 1.45, 4.61, p=0.001) respectively. CONCLUSION: We developed and validated a novel risk stratification system to predict reduced LAAev using clinical and echocardiographic variables. This may help refine the stratification of cardiogenic stroke risk.

18.
Biosens Bioelectron ; 267: 116793, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39316866

RESUMO

Pulse arrival time (PAT), Pulse transit time (PTT), and Pulse Wave Velocity (PWV) have all been used as metrics for assessing a number of cardiovascular applications, including arterial stiffness and cuffless blood pressure monitoring. These have been measured using various sensing methods, including electrocardiogram (ECG) with photoplethysmogram (PPG), two PPG sensors, or two Bioimpedance (BioZ) sensors. Our study addresses the mathematical inaccuracies of previous bioimpedance approaches and incorporates PTT weights for the peak-peak (PTTpp), middle-middle (PTTmm), and foot-foot (PTTff) segments of the sensing signal into a single neuron model to determine a more accurate and stable PWV. In addition, we developed a tetherless bioimpedance device and compared our PTT estimation approaches, which yielded PWV across six subjects and two different arteries. Specifically, using our model, we found that the most reliable combination of weights corresponding to PTTpp, PTTmm, and PTTff was (0.260, 0.704, 0.036) for the brachial artery and (0.104, 0.858, 0.038) for radial artery. This model consistently yielded stable values across repetitions, with PWV values of 5.2 m/s, 5.3 m/s, and 5.9 m/s for the brachial artery and values of 5.8 m/s, 6.6 m/s, and 6.5 m/s for the radial artery. This system and model offer the possibility of obtaining higher reliability PTT and PWV values yielding better monitoring of cardiovascular health measures such as blood pressure and arterial stiffness.

19.
Exp Physiol ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39320059

RESUMO

During unilateral static and rhythmic handgrip exercise, middle cerebral artery blood velocity (MCAv) increases in the contralateral side to the exercising limb. However, whether this neurovascular coupling-mediated increase in contralateral MCAv is apparent against a background of fluctuating perfusion pressure produced by dynamic resistance exercise (RE) is unclear. We examined the cerebral haemodynamic response to unilateral dynamic RE in 30 healthy individuals (female = 16, mean ± SD: age, 26 ± 6 years; height, 175 ± 10 cm; weight, 74 ± 15 kg; body mass index, 24 ± 5 kg m-2). Participants completed four sets of 10 paced repetitions (15 repetitions min-1) of unilateral bicep curl exercise at 60% of the predicted one-repetition maximum (7 ± 3 kg). Beat-to-beat blood pressure, bilateral MCAv and end-tidal carbon dioxide were measured throughout. One-way ANOVA was used to analyse cardiovascular variables and two-way ANOVA to analyse dependent cerebrovascular variables (side × sets, 2 × 5). A linear mixed model analysis was also performed to investigate the effects of end-tidal carbon dioxide and mean arterial blood pressure on MCAv. In comparison to baseline, within-exercise mean arterial blood pressure increased (P < 0.001) across the sets, whereas bilateral MCAv decreased (P < 0.001). However, no significant interaction effect was observed for any dependent variables (all P > 0.787). The linear mixed model revealed that end-tidal carbon dioxide had the greatest effect on MCAv (estimate = 1.019, t = 8.490, P < 0.001). No differences were seen in contralateral and ipsilateral MCAv during dynamic RE, suggesting that neurovascular coupling contributions during dynamic RE might be masked by other regulators, such as blood pressure.

20.
Ageing Res Rev ; 101: 102501, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39303876

RESUMO

BACKGROUND: Higher levels of pulse wave velocity (PWV) have been related with the presence of small vessel disease that could damage the brain, in which white matter hyperintensities (WMH) could be presented as consequence. This meta-analysis aims to examine the cross-sectional and longitudinal associations between PWV and the presence of WMH among older adults. METHODS: We searched PubMed, Scopus, and WOS until June 2024. Pooled Odds Ratio (p-OR) were estimated for the cross-sectional and longitudinal associations between PWV and WMH. In addition, we explored whether this associations could be modified by type of PWV measurement and study and sample characteristics. RESULTS: The p-OR between PWV and WMH was 1.16 (95 % CI, 1.10-1.22) for the cross-sectional and 1.07 (95 %, 1.00-1.15) for the longitudinal association. Similar figures were found by type of PWV measurement and no one of the explored characteristics modified this associations. CONCLUSIONS: This meta-analysis revealed that the presence in and the long-term development of WMHs among older adults are more likely among those with elevated PWV.

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