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1.
J Med Biochem ; 43(4): 587-596, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-39139162

RESUMEN

Background: To explore the correlation between left atrial appendage morphology, blood flow velocity and plasma galectin-3 and thrombosis in patients with atrial fibrillation. Methods: Patients with atrial fibrillation who received treatment and completed ultrasound examination in hospital from 2022 to December 2023 were enrolled. According to whether there was left atrial appendage thrombosis, the patients were divided into a control group (no left atrial appendage thrombosis was found) and a study group (left atrial appendage thrombosis was found). The morphology and structure of the left atrial appendage, blood flow velocity and plasma galectin-3 level were recorded exploring its correlation with left atrium thrombosis. Results: A total of 330 patients with atrial fibrillation were enrolled, including 278 in the control group and 52 in the study group. Left group and the control group of morphological structure differences (P < 0.05). The main lobe length, ostial area, longest diameter, shortest diameter, left atrial appendage volume and left atrial volume in the study group were higher than those in the control group (P < 0.05). The left atrial appendage emptying velocity, filling velocity and left ventricular ejection fraction of the study group were lower than those of the control group, and the left ventricular end-diastolic diameter was higher than that of the control group (P < 0.05). Group of white blood cell count, neutrophils/lymphocyte ratio, plasma galactose lectin-3 levels were higher than control group (P < 0.05). ROC curve analysis of left atrial appendage emptying velocity, left atrial appendage filling velocity, left atrial enddiastolic diameter and left atrial ejection fraction had higher diagnostic value (P < 0.05). Conclusions: Left atrial appendage morphology, blood flow velocity and plasma galectin-3 level are important factors to evaluate the risk of left atrial appendage thrombosis in patients with atrial fibrillation. This study improves the understanding of thrombosis, further elucidates the risk factors for thrombosis, and improves patient prognosis.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39147264

RESUMEN

BACKGROUND: Nocturnal shoulder pain is seen in patients with rotator cuff tears. The purpose of the present study was to determine whether Doppler ultrasound parameters predict the intensity of nocturnal pain in patients with rotator cuff tears. METHODS: A total of 60 patients with rotator cuff tears were included. Doppler ultrasound parameters (peak systolic velocity in the anterior humeral circumflex artery, Doppler activity in the glenohumeral joint and subacromial space) and clinical parameters were examined. For the presence of nocturnal pain, the clinical parameters were compared with and without nocturnal pain. For the intensity of the nocturnal pain, a multivariate analysis of clinical parameters and nocturnal pain intensity was performed. RESULTS: In all, 39 patients (65%) reported nocturnal pain, and the mean pain intensity was 47.0 (standard deviation, 26.0) on the visual analogue scale. In nocturnal pain presence analysis, Doppler activity in the subacromial space showed significant associations (p < 0.001). In nocturnal pain intensity analysis, Doppler activity in the subacromial space and diabetes showed significant associations (p < 0.001, p = 0.01, respectively). CONCLUSION: Doppler activity in the subacromial space emerges as an independent factor associated with the presence and intensity of nocturnal pain in patients with rotator cuff tears. Our findings may provide a basis for further exploration and refinement of treatment strategies.

3.
J Periodontal Res ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090529

RESUMEN

AIM: The aim of this study is to assess early wound healing expression of local angiogenic biomarkers following connective tissue graft (CTG) at dental implant sites. METHODS: Twenty-eight subjects with single dental implants exhibiting a soft tissue dehiscence were included and randomly treated with CTG, either with coronally advanced flap (CAF) or with tunnel technique (TUN). Peri-implant crevicular fluid (PICF) was collected at the midfacial and midlingual aspect of the implant sites at baseline and at 3, 7, 14, 30, and 90 days after the surgical intervention. The expression of angiogenin (ANG), fibroblast growth factor-2 (FGF-2), platelet-derived growth factor (PDGF), tissue inhibitor of metalloproteinases-2 (TIMP-2), and vascular endothelial growth factor (VEGF) was investigated over a period of 3 months. Patient-reported outcomes, clinical measurements, and ultrasonography scans at multiple time points were also evaluated. RESULTS: The longitudinal regression revealed a significant difference in the expression of VEGF and TIMP-2 between CAF- and TUN-treated sites over 3 months (p = .033 and p = .004, respectively), whereas no significant differences were observed for ANG, FGF-2 and PDGF between the two groups. At 7 days, a direct correlation was observed between ANG levels and ultrasonographic color velocity in the CAF group (p < .001) and between ANG levels and ultrasonographic color power in the TUN group (p = .028). VEGF levels and ultrasonographic mean perfused area of the CTG were significantly correlated at the 7-day time point (p < .001 for both CAF and TUN). The expression of VEGF at 7 days was directly associated with mucosal thickness gain at 1 year (p < .001 for both groups). Early TIMP-2 expression showed an inverse correlation with time to recovery (p = .002). TIMP-2 levels at 3 months exhibited inverse correlations with mean dehiscence coverage (p = .004) and the rate of complete dehiscence coverage (p = .012). CONCLUSION: PICF biomarkers can be used to monitor early wound healing events following soft tissue grafting at implant sites. VEGF and TIMP-2 showed correlations with the 1-year clinical and volumetric outcomes, as well as with post-operative patient-reported outcomes and Doppler Ultrasonographic tissue perfusion-related parameters.

4.
Int J Sports Physiol Perform ; 19(9): 932-938, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39043362

RESUMEN

PURPOSE: There are multiple postexercise recovery technologies available in the market based on the assumption of blood-flow enhancement. Lower-limb intermittent pneumatic compression (IPC) has been widely used, but the available scientific evidence supporting its effectiveness remains scarce, requiring a deeper investigation into its underlying mechanisms. The aim of this study was to assess the hemodynamic effects caused by the use of IPC at rest. METHODS: Twenty-two soccer and track and field athletes underwent two 15-minute IPC protocols (moderate- [80 mm Hg] and high-pressure [200 mm Hg]) in a randomized order. Systolic peak velocity, end-diastolic peak velocity, arterial diameter, and heart rate were measured before, during (at the eighth minute), and 2 minutes after each IPC protocol. RESULTS: Significant effects were observed between before and during (eighth minute) the IPC protocol for measures of systolic (P < .001) and end-diastolic peak velocities (P < .001), with the greater effects observed during the high-pressure protocol. Moreover, 2 minutes after each IPC protocol, hemodynamic variables returned to values close to baseline. Arterial diameter presented significant differences between pressures during the IPC protocols (P < .05), while heart rate remained unaltered. CONCLUSION: IPC effectively enhances transitory blood flow of athletes, particularly when applying high-pressure protocols.


Asunto(s)
Estudios Cruzados , Frecuencia Cardíaca , Hemodinámica , Aparatos de Compresión Neumática Intermitente , Fútbol , Humanos , Fútbol/fisiología , Frecuencia Cardíaca/fisiología , Masculino , Hemodinámica/fisiología , Adulto Joven , Método Doble Ciego , Atletismo/fisiología , Adulto , Velocidad del Flujo Sanguíneo/fisiología , Atletas , Flujo Sanguíneo Regional , Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/fisiología
5.
Ann Intensive Care ; 14(1): 108, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980442

RESUMEN

BACKGROUND: Dynamic arterial elastance (Eadyn) has been investigated for its ability to predict hypotension during the weaning of vasopressors. Our study focused on assessing Eadyn's performance in the context of critically ill adult patients admitted to the intensive care unit, regardless of diagnosis. MAIN BODY: Our study was conducted in accordance with the Preferred Reported Items for Systematic Reviews and Meta-Analysis checklist. The protocol was registered in PROSPERO (CRD42023421462) on May 26, 2023. We included prospective observational studies from the MEDLINE and Embase databases through May 2023. Five studies involving 183 patients were included in the quantitative analysis. We extracted data related to patient clinical characteristics, and information about Eadyn measurement methods, results, and norepinephrine dose. Most patients (76%) were diagnosed with septic shock, while the remaining patients required norepinephrine for other reasons. The average pressure responsiveness rate was 36.20%. The synthesized results yielded an area under the curve of 0.85, with a sensitivity of 0.87 (95% CI 0.74-0.93), specificity of 0.76 (95% CI 0.68-0.83), and diagnostic odds ratio of 19.07 (95% CI 8.47-42.92). Subgroup analyses indicated no variations in the Eadyn based on norepinephrine dosage, the Eadyn measurement device, or the Eadyn diagnostic cutoff to predict cessation of vasopressor support. CONCLUSIONS: Eadyn, evaluated through subgroup analyses, demonstrated good predictive ability for the discontinuation of vasopressor support in critically ill patients.

6.
Sensors (Basel) ; 24(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-39001186

RESUMEN

INTRODUCTION: Concussion is known to cause transient autonomic and cerebrovascular dysregulation that generally recovers; however, few studies have focused on individuals with an extensive concussion history. METHOD: The case was a 26-year-old male with a history of 10 concussions, diagnosed for bipolar type II disorder, mild attention-deficit hyperactivity disorder, and a history of migraines/headaches. The case was medicated with Valproic Acid and Escitalopram. Sensor-based baseline data were collected within six months of his injury and on days 1-5, 10, and 14 post-injury. Symptom reporting, heart rate variability (HRV), neurovascular coupling (NVC), and dynamic cerebral autoregulation (dCA) assessments were completed using numerous biomedical devices (i.e., transcranial Doppler ultrasound, 3-lead electrocardiography, finger photoplethysmography). RESULTS: Total symptom and symptom severity scores were higher for the first-week post-injury, with physical and emotional symptoms being the most impacted. The NVC response showed lowered activation in the first three days post-injury, while autonomic (HRV) and autoregulation (dCA) were impaired across all testing visits occurring in the first 14 days following his concussion. CONCLUSIONS: Despite symptom resolution, the case demonstrated ongoing autonomic and autoregulatory dysfunction. Larger samples examining individuals with an extensive history of concussion are warranted to understand the chronic physiological changes that occur following cumulative concussions through biosensing devices.


Asunto(s)
Conmoción Encefálica , Frecuencia Cardíaca , Humanos , Masculino , Adulto , Conmoción Encefálica/fisiopatología , Conmoción Encefálica/diagnóstico por imagen , Frecuencia Cardíaca/fisiología , Sistema Nervioso Autónomo/fisiopatología , Electrocardiografía/métodos , Acoplamiento Neurovascular/fisiología , Fotopletismografía/métodos , Ultrasonografía Doppler Transcraneal/métodos
7.
Physiol Rep ; 12(13): e16137, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38969625

RESUMEN

Post-traumatic stress disorder (PTSD) is associated with increased cardiovascular disease (CVD) risk. Compared with males, females are twice as likely to develop PTSD after trauma exposure, and cardiovascular reactivity to stress is a known risk factor for CVD. We aimed to examine hemodynamic responses to acute mental stress in trauma-exposed females with and without a clinical diagnosis of PTSD. We hypothesized that females with PTSD would have higher heart rate (HR), blood pressure (BP), and lower blood flow velocity (BFV) responsiveness compared with controls. We enrolled 21 females with PTSD and 21 trauma-exposed controls. We continuously measured HR using a three-lead electrocardiogram, BP using finger plethysmography, and brachial BFV using Doppler ultrasound. All variables were recorded during 10 min of supine rest, 5 min of mental arithmetic, and 5 min of recovery. Females with PTSD were older, and had higher BMI and higher resting diastolic BP. Accordingly, age, BMI, and diastolic BP were covariates for all repeated measures analyses. Females with PTSD had a blunted brachial BFV response to mental stress (time × group, p = 0.005) compared with controls, suggesting greater vasoconstriction. HR and BP responses were comparable. In conclusion, our results suggest early impairment of vascular function in premenopausal females with PTSD.


Asunto(s)
Presión Sanguínea , Arteria Braquial , Frecuencia Cardíaca , Trastornos por Estrés Postraumático , Estrés Psicológico , Humanos , Femenino , Adulto , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/diagnóstico por imagen , Estrés Psicológico/fisiopatología , Arteria Braquial/fisiopatología , Arteria Braquial/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Frecuencia Cardíaca/fisiología , Presión Sanguínea/fisiología , Persona de Mediana Edad
8.
J Clin Med ; 13(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38999540

RESUMEN

Background: This pilot study aimed to evaluate the Retinal Function Imager (RFI) for visualizing retinal vasculature and assessment of blood flow characteristics in patients with retinal vasculitis. The RFI is a non-invasive imaging device measuring the blood flow velocity (BFV) in secondary and tertiary retinal vessels using hemoglobin as an intrinsic motion-contrast agent. Methods: To test the feasibility of the RFI for patients with retinal vasculitis, capillary perfusion maps (nCPMs) were generated from 15 eyes of eight patients (five females; mean age: 49 ± 12 years) with a mean uveitis duration of 74 ± 85 months. Five of these patients had birdshot chorioretinopathy, and three had primarily non-occlusive venous retinal vasculitis of unknown origin. To reflect that the BFV may be more reduced in patients with prolonged disease, patients were classified into a short-term (uveitis duration: 8-15 months) and a long-term uveitis group (uveitis duration: 60-264 months). Data were compared with healthy controls (16 eyes of 11 patients; mean age 45 ± 12 years; 8 females). Results: The mean BFV in the controls was 3.79 ± 0.50 mm/s in the retinal arteries and 2.35 ± 0.44 mm/s in the retinal veins, which was significantly higher compared to the retinal vasculitis group. Patients revealed an arterial BFV of 2.75 ± 0.74 mm/s (p < 0.001) and a venous BFV of 1.75 ± 0.51 mm/s (p = 0.016). In the short-term group, a trend towards a decreased venular and arteriolar BFV was seen, while a significant reduction was observed in the long-term group. The patients' microvasculature anatomy revealed by the nCPMs appeared unevenly distributed and a lower number of blood vessels were seen, along with a lower degree of complexity of their branching patterns, when compared with controls. Conclusions: This study demonstrated a reduction in venular and arteriolar BFVs in patients with retinal vasculitis. BFV alterations were already observed in early disease stages and became more pronounced in progressed disease. Additionally, we showed that retinal microvasculature changes may be observed by nCPMs. Retinal imaging with the RFI may serve as a diagnostic and quantifying tool in retinal vasculitis.

9.
Front Nutr ; 11: 1398108, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39027664

RESUMEN

Background: Peripheral arterial disease (PAD) is a prevalent vascular disorder characterized by atherosclerotic occlusion of peripheral arteries, resulting in reduced blood flow to the lower extremities and poor walking ability. Older patients with PAD are also at a markedly increased risk of cardiovascular events, including myocardial infarction. Recent evidence indicates that inorganic nitrate supplementation, which is abundant in certain vegetables, augments nitric oxide (NO) bioavailability and may have beneficial effects on walking, blood pressure, and vascular function in patients with PAD. Objective: We sought to determine if short-term nitrate supplementation (via beetroot juice) improves peak treadmill time and coronary hyperemic responses to plantar flexion exercise relative to placebo (nitrate-depleted juice) in older patients with PAD. The primary endpoints were peak treadmill time and the peak coronary hyperemic response to plantar flexion exercise. Methods: Eleven PAD patients (52-80 yr.; 9 men/2 women; Fontaine stage II) were randomized (double-blind) to either nitrate-rich (Beet-IT, 0.3 g inorganic nitrate twice/day; BRnitrate) or nitrate-depleted (Beet-IT, 0.04 g inorganic nitrate twice/day, BRplacebo) beetroot juice for 4 to 6 days, followed by a washout of 7 to 14 days before crossing over to the other treatment. Patients completed graded plantar flexion exercise with their most symptomatic leg to fatigue, followed by isometric handgrip until volitional fatigue at 40% of maximum on day 4 of supplementation, and a treadmill test to peak exertion 1-2 days later while continuing supplementation. Hemodynamics and exercise tolerance, and coronary blood flow velocity (CBV) responses were measured. Results: Although peak walking time and claudication onset time during treadmill exercise did not differ significantly between BRplacebo and BRnitrate, the diastolic blood pressure response at the peak treadmill walking stage was significantly lower in the BRnitrate condition. Increases in CBV from baseline to peak plantar flexion exercise after BRplacebo and BRnitrate showed a trend for a greater increase in CBV at the peak workload of plantar flexion with BRnitrate (p = 0.06; Cohen's d = 0.56). Conclusion: Overall, these preliminary findings suggest that inorganic nitrate supplementation in PAD patients is safe, well-tolerated, and may improve the coronary hyperemic and blood pressure responses when their calf muscles are most predisposed to ischemia.Clinical trial registration:https://clinicaltrials.gov/, identifier NCT02553733.

10.
Ann Vasc Dis ; 17(2): 205-210, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38919313

RESUMEN

In this series of three cases, we describe the vascular steal phenomenon in an otherwise normal lower limb secondary to hyperemia in the contralateral lower limb. In each of the cases, post-inflammatory hyperemia in the involved lower limb was associated with a significant reduction in blood flow in the contralateral normal lower limb. We attempt to explain the imaging findings in these three cases using the equation of continuity in fluid dynamics. To the best of our knowledge, a description of such kind is unavailable in the published literature.

11.
J Clin Med ; 13(11)2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38892827

RESUMEN

Background: Transcatheter interventions are increasingly used in children with congenital heart disease. However, these interventions can affect cardiac output and cerebral circulation. In this pilot study, we aimed to investigate the use of NeoDoppler, a continuous transfontanellar cerebral Doppler monitoring system, to evaluate the impact of transcatheter interventions on cerebral circulation. Methods: Nineteen participants under one year of age (mean age 3.5 months) undergoing transcatheter cardiac interventions were prospectively included. Transfontanellar cerebral Doppler monitoring with the NeoDoppler system was initiated after intubation and continued until the end of the procedure. Results: Instant detection of changes in cerebral blood flow were observed across a spectrum of transcatheter interventions. Balloon aortic valvuloplasty demonstrated temporary cessation of cerebral blood flow during balloon inflation. Increase in cerebral diastolic blood flow velocity and decreased pulsatility were observed during patent ductus arteriosus occlusion. Changes in cerebral blood flow patterns were detected in two patients who encountered complications during their transcatheter interventions. There was no significant change in Doppler parameters before and after the interventions for the entire patient group. High quality recordings were achieved in 87.3% of the monitoring period. Conclusions: Continuous transfontanellar cerebral Doppler is feasible in monitoring cerebral hemodynamic trends and shows instantaneous changes associated with interventions and complications. It could become a useful monitoring tool during transcatheter interventions in infants.

12.
J Clin Med ; 13(11)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38892865

RESUMEN

Background/Objectives: This study aimed to investigate the relationship between posterior tibial artery blood flow velocity and plantar heel pain (PHP). Methods: The PHP group comprised patients diagnosed with plantar fasciitis with plantar heel pain during gait, and the control group comprised healthy participants without plantar heel pain. The peak systolic velocity of the posterior tibial artery was measured using ultrasonography; it was measured three times on each side, and the mean value was calculated. Receiver operating characteristic curve analysis was performed to calculate the peak systolic velocity cutoff value for plantar heel pain. Results: 23 patients (age 58.0 ± 16.5 years; 13 males and 10 females) and 23 healthy participants (age 51.3 ± 17.3 years; 10 males and 13 females) formed the PHP and control groups, respectively. Peak systolic velocity on the affected side was significantly greater in the PHP group (44.1 ± 13.1 cm/s) than in the control group (32.7 ± 5.9 cm/s). No significant difference was observed between the left and right sides in the PHP (7.1 ± 9.8 cm/s) and control (3.7 ± 3.0 cm/s) groups. A cutoff value of 38.2 cm/s was observed on the affected side. Conclusions: We quantified the increase in posterior tibial artery blood flow velocity in patients with plantar heel pain. Peak systolic velocity measurements can aid in quantitatively evaluating these patients. This study was registered as a clinical trial (UMIN000046875) on 1 October 2021.

13.
Brain Spine ; 4: 102832, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756859

RESUMEN

Introduction: Both intracranial pressure (ICP) and cerebral arterial blood volume (CaBV) have a pulsatile character related to the cardiac cycle. The evolution of the shape of ICP pulses under increasing ICP or decreasing intracranial compliance is well documented. Nevertheless, the exact origin of the alterations in the ICP morphology remains unclear. Research question: Does ICP pulse waveform become similar to non-invasively estimated CaBV pulse during ICP plateau waves. Material and methods: A total of 15 plateau waves recorded in 15 traumatic brain injured patients were analyzed. CaBV pulse waveforms were calculated using global cerebral blood flow model from transcranial Doppler cerebral blood flow velocity (CBFV) signals. The difference index (DI) was used to quantify the similarity between ICP and CaBV waveforms. DI was calculated as the sum of absolute sample-by-sample differences between ICP and CaBV waveforms, representing the area between the pulses. Results: ICP increased (19.4 mm Hg [Q1-Q3: 18.2-23.4 mm Hg] vs. 42.7 mm Hg [Q1-Q3: 36.5-45.1 mm Hg], p < 0.001) while CBFV decreased (44.2 cm/s [Q1-Q3: 34.8-69.5 cm/s] vs. 32.9 cm/s [Q1-Q3: 24.7-68.2 cm/s], p = 0.002) during plateau waves. DI was smaller during the plateau waves (20.4 [Q1-Q3: 15.74-23.0]) compared to the baselines (26.3 [Q1-Q3: 24.2-34.7], p < 0.001). Discussion and conclusion: The area between corresponding ICP and CaBV pulse waveforms decreased during the plateau waves which suggests they became similar in shape. CaBV may play a significant role in determining the shape of ICP pulses during the plateau waves and might be a driving force in formulating ICP elevation.

14.
Healthcare (Basel) ; 12(10)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38786378

RESUMEN

BACKGROUND AND PURPOSE: Early differentiation between acute ischaemic (AIS) and haemorrhagic stroke (ICH), based on cerebral and peripheral hemodynamic parameters, would be advantageous to allow for pre-hospital interventions. In this preliminary study, we explored the potential of multiple parameters, including dynamic cerebral autoregulation, for phenotyping and differentiating each stroke sub-type. METHODS: Eighty patients were included with clinical stroke syndromes confirmed by computed tomography within 48 h of symptom onset. Continuous recordings of bilateral cerebral blood velocity (transcranial Doppler ultrasound), end-tidal CO2 (capnography), electrocardiogram (ECG), and arterial blood pressure (ABP, Finometer) were used to derive 67 cerebral and peripheral parameters. RESULTS: A total of 68 patients with AIS (mean age 66.8 ± SD 12.4 years) and 12 patients with ICH (67.8 ± 16.2 years) were included. The median ± SD NIHSS of the cohort was 5 ± 4.6. Statistically significant differences between AIS and ICH were observed for (i) an autoregulation index (ARI) that was higher in the unaffected hemisphere (UH) for ICH compared to AIS (5.9 ± 1.7 vs. 4.9 ± 1.8 p = 0.07); (ii) coherence function for both hemispheres in different frequency bands (AH, p < 0.01; UH p < 0.02); (iii) a baroreceptor sensitivity (BRS) for the low-frequency (LF) bands that was higher for AIS (6.7 ± 4.2 vs. 4.10 ± 2.13 ms/mmHg, p = 0.04) compared to ICH, and that the mean gain of the BRS in the LF range was higher in the AIS than in the ICH (5.8 ± 5.3 vs. 2.7 ± 1.8 ms/mmHg, p = 0.0005); (iv) Systolic and diastolic velocities of the affected hemisphere (AH) that were significantly higher in ICH than in AIS (82.5 ± 28.09 vs. 61.9 ± 18.9 cm/s), systolic velocity (p = 0.002), and diastolic velocity (p = 0.05). CONCLUSION: Further multivariate modelling might improve the ability of multiple parameters to discriminate between AIS and ICH and warrants future prospective studies of ultra-early classification (<4 h post symptom onset) of stroke sub-types.

15.
Korean J Ophthalmol ; 38(2): 147-155, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38476060

RESUMEN

PURPOSE: Autoregulation of retinal vessels is stronger than that of choroidal vessels. This study aimed to use laser speckle flowgraphy to determine the time course of changes in retinal hemodynamics of healthy eyes after a cold pressor test. METHODS: This prospective study included 44 right eyes of 44 healthy volunteers (age, 21.7 ± 5.0 years). The mean blur rate, which is a quantitative index of the relative blood flow velocity in the retina, was measured using laser speckle flowgraphy. The vessel average of mean blur rate at the optic nerve head, intraocular pressure, systolic blood pressure, diastolic blood pressure, mean blood pressure, heart rate, and ocular perfusion pressure were evaluated at baseline, immediately after the cold pressor test, and 10, 20, and 30 minutes after the test. RESULTS: Immediately after the test (0 minutes), systolic blood pressure, diastolic blood pressure, mean blood pressure, and ocular perfusion pressure were significantly increased compared with those at baseline; however, no changes were observed at 10, 20, and 30 minutes after the test. In contrast, intraocular pressure, heart rate, and the vascular mean blur rate values at the optic nerve head did not change throughout the course of the study. CONCLUSIONS: Sympathetic hyperactivity induced by the cold pressor test increased systemic circulatory dynamics, but not retinal circulatory hemodynamics, suggesting the involvement of vascular autoregulation.


Asunto(s)
Disco Óptico , Humanos , Adolescente , Adulto Joven , Adulto , Voluntarios Sanos , Estudios Prospectivos , Hemodinámica , Presión Sanguínea/fisiología , Presión Intraocular , Rayos Láser , Flujo Sanguíneo Regional/fisiología
16.
Adv Neurobiol ; 36: 385-396, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38468043

RESUMEN

The cerebrovascular system is characterized by parameters such as arterial blood pressure (ABP), cerebral perfusion pressure (CPP), and cerebral blood flow velocity (CBFV). These are regulated by interconnected feedback loops resulting in a fluctuating and complex time course. They exhibit fractal characteristics such as (statistical) self-similarity and scale invariance which could be quantified by fractal measures. These include the coefficient of variation, the Hurst coefficient H, or the spectral exponent α in the time domain, as well as the spectral index ß in the frequency domain. Prior to quantification, the time series has to be classified as either stationary or nonstationary, which determines the appropriate fractal analysis and measure for a given signal class. CBFV was characterized as a nonstationary (fractal Brownian motion) signal with spectral index ß between 2.0 and 2.3. In the high-frequency range (>0.15 Hz), CBFV variability is mainly determined by the periodic ABP variability induced by heartbeat and respiration. However, most of the spectral power of CBFV is contained in the low-frequency range (<0.15 Hz), where cerebral autoregulation acts as a low-pass filter and where the fractal properties are found. Cerebral vasospasm, which is a complication of subarachnoid hemorrhage (SAH), is associated with an increase in ß denoting a less complex time course. A reduced fractal dimension of the retinal microvasculature has been observed in neurodegenerative disease and in stroke. According to the decomplexification theory of illness, such a diminished complexity could be explained by a restriction or even dropout of feedback loops caused by disease.


Asunto(s)
Fractales , Enfermedades Neurodegenerativas , Humanos , Presión Sanguínea/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Circulación Cerebrovascular/fisiología
17.
Eur Radiol Exp ; 8(1): 45, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38472565

RESUMEN

BACKGROUND: Phase-contrast magnetic resonance imaging (PC-MRI) quantifies blood flow and velocity noninvasively. Challenges arise in neurovascular disorders due to small vessels. We evaluated the impact of voxel size, number of signal averages (NSA), and velocity encoding (VENC) on PC-MRI measurement accuracy and precision in a small-lumen vessel phantom. METHODS: We constructed an in vitro model with a constant flow rate using a 2.2-mm inner diameter plastic tube. A reservoir with a weight scale and timer was used as standard reference. Gradient-echo T1 weighted PC-MRI sequence was performed on a 3-T scanner with varying voxel size (2.5, 5.0, 7.5 mm3), NSA (1, 2, 3), and VENC (200, 300, 400 cm/s). We repeated measurements nine times per setting, calculating mean flow rate, maximum velocity, and least detectable difference (LDD). RESULTS: PC-MRI flow measurements were higher than standard reference values (mean ranging from 7.3 to 9.5 mL/s compared with 6.6 mL/s). Decreased voxel size improved accuracy, reducing flow rate measurements from 9.5 to 7.3 mL/s. The LDD for flow rate and velocity varied between 1 and 5%. The LDD for flow rate decreased with increased voxel size and NSA (p = 0.033 and 0.042). The LDD for velocity decreased with increased voxel size (p < 10-16). No change was observed when VENC varied. CONCLUSIONS: PC-MRI overestimated flow. However, it has high precision in a small-vessel phantom with constant flow rate. Improved accuracy was obtained with increasing spatial resolution (smaller voxels). Improved precision was obtained with increasing signal-to-noise ratio (larger voxels and/or higher NSA). RELEVANCE STATEMENT: Phase-contrast MRI is clinically used in large vessels. To further investigate the possibility of using phase-contrast MRI for smaller intracranial vessels in neurovascular disorders, we need to understand how acquisition parameters affect phase-contrast MRI-measured flow rate and velocity in small vessels. KEY POINTS: • PC-MRI measures flow and velocity in a small lumen phantom with high precision but overestimates flow rate. • The precision of PC-MRI measurements matches the precision of standard reference for flow rate measurements. • Optimizing PC-MRI settings can enhance accuracy and precision in flow rate and velocity measurements.


Asunto(s)
Imagen por Resonancia Magnética , Velocidad del Flujo Sanguíneo/fisiología , Imagen por Resonancia Magnética/métodos , Relación Señal-Ruido , Fantasmas de Imagen , Reproducibilidad de los Resultados
18.
BMC Anesthesiol ; 24(1): 66, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38378447

RESUMEN

BACKGROUND: Esketamine is increasingly used in clinical anesthesia. The effect of esketamine on the blood flow velocity of the middle cerebral artery has a clinical guiding effect. To investigate the effect of esketamine combined with propofol-induced general anesthesia for endotracheal intubation on the blood flow velocity of middle cerebral artery and hemodynamics during the induction period. METHODS: The randomized clinical trial included 80 patients aged 20-65 years who would undergo non-intracranial elective surgery under general anesthesia in our hospital from May 2022 to May 2023. The participants were divided into two groups based on anesthesia drugs: sufentanil 0.5µg/kg (group C) or 1.5mg/kg esketamine (group E). The primary outcome was variation value in average cerebral blood velocity. The secondary outcomes included cerebral blood flow velocities (CBFV), blood pressure (BP) and heart rate (HR) at four different time points: before induction of general anesthesia (T0), 1 min after the induction drug injected (T1), before endotracheal intubation (T2), and 1min after endotracheal intubation (T3). The occurrence of hypotension, hypertension, tearing and choking during induction was also documented. RESULTS: The variation of average CBFV from time T0 to T2(ΔVm1) and the variation from time T3 to T0 (ΔVm2) were not obviously different. The median consumption of intraoperative sufentanil in group C was obviously lower than that in group E. At T1, the mean HR of group E was significantly higher than that of group C. At T2 and T3, the BP and HR of group E were obviously higher than that of group C. At T2, the CBFV in the group E were obviously higher than those in the group C. The incidence of hypotension was significantly reduced in the group E compared with the group C. There were no differences in the other outcomes. CONCLUSIONS: The induction of esketamine combined with propofol does not increase the blood flow velocity of middle cerebral artery. Esketamine is advantageous in maintaining hemodynamic stability during induction. Furthermore, the administration of esketamine did not result in an increased incidence of adverse effects. TRIAL REGISTRATION: 15/06/2023 clinicaltrials.gov ChiCTR2300072518 https://www.chictr.org.cn/bin/project/edit?pid=176675 .


Asunto(s)
Ketamina , Propofol , Humanos , Anestesia General , Circulación Cerebrovascular , Hipotensión , Ketamina/farmacología , Propofol/farmacología , Sufentanilo/farmacología , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano
19.
BMC Pulm Med ; 24(1): 77, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336639

RESUMEN

OBJECTIVE: This study aimed to investigate the risk factors for peripheral arteriosclerosis (PAS) and peripheral artery disease (PAD) in chronic obstructive pulmonary disease (COPD) patients and potential ultrasound indicators that could be used to improve detection. METHOD: Outpatients seeking care between January 1, 2017, and December 31, 2020, in The First Affiliated Hospital of China Medical University were prospectively recruited. Subjects were divided into COPD and non-COPD (control) groups, and the COPD group was further divided into PAD and non-PAD subgroup, at the same time, PAS and non-PAS subgroup. Indicators of PAD -ankle-brachial index (ABI), indicators of PAS- pulse wave velocity (PWV), and ultrasound indices -peak systolic blood flow velocity (PSV) and blood flow acceleration velocity (AccV) were compared. RESULT: Sixty-nine (61.6%) of 112 enrolled subjects had COPD. COPD patients had higher age, and blood pressure (BP)lower than controls. Seventeen (24.6%) COPD patients had PAD, the prevalence of PAD increases with the decrease of lung function, and seven (16.3%) non-COPD patients had PAD, however, there was no significant statistical difference between COPD and non-COPD groups. Fifty (72.5%) COPD patients had PAS, and thirty-four (79.1%) non-COPD patients had PAS, however, there was also no significant difference. The PAS subgroup had higher age, body mass index(BMI), body fat percentage(BFP), lower FEV1 and FEV1/FVC, as well as higher levels of right brachial artery and left dorsalis pedis artery AccV. Factors that correlated with ABI were 6MWD, post-bronchodilator FEV1, FEV1/ FVC, and maximal middle expiratory flow between 75% and 25% of FVC. Age, BP, and 6MWD, but not pulmonary function, were associated with brachial-ankle PWV (baPWV). There was a positive correlation between baPWV and radial artery AccV bilaterally. CONCLUSION: Radial artery AccV correlated well with baPWV, which suggests that ultrasound could be used to assess both morphological and functional changes in vessels, may serving as a better method to identify PAS in high-risk COPD patients.


Asunto(s)
Enfermedad Arterial Periférica , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Análisis de la Onda del Pulso , Ultrasonido , Arteria Braquial/diagnóstico por imagen , Enfermedad Arterial Periférica/epidemiología
20.
Am J Physiol Heart Circ Physiol ; 326(4): H923-H928, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38334969

RESUMEN

It is known that electrical muscle stimulation (EMS) can enhance physical function, but its impact on cognition and cerebral hemodynamics is not well understood. Thus, the purpose of this study was to investigate the effects of one EMS session on cerebrovascular function and cognitive performance. The 17 recruited young healthy participants undertook a 25-min session of EMS and a resting control session (Ctrl group) in a random order. Cerebral blood flow velocity (CBFv) in the middle and posterior cerebral arteries (right MCAv and left PCAv, respectively), cerebral oxygenation, cardiac output, and heart rate were measured throughout the sessions, whereas cognitive function was assessed before and after each experimental condition. MCAv, cardiac output, heart rate, and cerebral oxygenation were increased throughout the EMS session, whereas PCAv remained unchanged. In addition, EMS led to improved scores at the Rey auditory verbal learning test-part B and congruent Stroop task versus Ctrl. The present study demonstrates that a single session of EMS may improve cognitive performance and concomitantly increase CBFv and cerebral oxygenation. Therefore, EMS appears to be a valuable surrogate for voluntary exercise and could therefore be advantageously used in populations with severe physical limitations who would not be able to perform physical exercise otherwise.NEW & NOTEWORTHY This study is the first to demonstrate that one session of EMS applied to the quadriceps increases cerebral blood flow velocity and cerebral oxygenation, which are pivotal factors for brain health. Thus, EMS has the potential to be used as an interesting option in rehabilitation to increase cerebral perfusion and defend if not improve cognitive function sustainably for people with severe physical limitations who would not be able to perform physical exercise voluntarily.


Asunto(s)
Circulación Cerebrovascular , Hemodinámica , Humanos , Encéfalo/irrigación sanguínea , Circulación Cerebrovascular/fisiología , Cognición , Hemodinámica/fisiología , Músculo Cuádriceps
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