Search Results (100)

Continuous blood pressure (BP) monitoring provides valuable insight into the body’s dynamic cardiovascular regulation across various physiological states such as physical activity, emotional stress, postural changes, and sleep. Continuous BP monitoring captures different variations in systolic and diastolic pressures, reflecting autonomic nervous system activity, vascular compliance, and circadian rhythms. This enables early identification of abnormal BP trends and allows for timely diagnosis and interventions to reduce the risk of cardiovascular diseases (CVDs) such as hypertension, stroke, heart failure, and chronic kidney disease as well as chronic stress or anxiety disorders. To facilitate continuous BP monitoring, we propose an AI-powered estimation framework. The proposed framework first uses an expert-driven feature engineering approach that systematically extracts physiological features from photoplethysmogram (PPG)-based arterial pulse waveforms (APWs). Extracted features include pulse rate, ascending/descending times, pulse width, slopes, intensity variations, and waveform areas. These features are fused with demographic data (age, gender, height, weight, BMI) to enhance model robustness and accuracy across diverse populations. The framework utilizes a Tab-Transformer to learn rich feature embeddings, which are then processed through an ensemble machine learning framework consisting of CatBoost, XGBoost, and LightGBM. Evaluated on a dataset of 1000 subjects, the model achieves Mean Absolute Errors (MAE) of 3.87 mmHg (SBP) and 2.50 mmHg (DBP), meeting British Hypertension Society (BHS) Grade A and Association for the Advancement of Medical Instrumentation (AAMI) standards. The proposed architecture advances non-invasive, AI-driven solutions for dynamic cardiovascular health monitoring. Full article

Polyvinyl alcohol cryogels (PVA-C) are promising materials for vascular tissue engineering due to their biocompatibility, hydrophilicity, and tuneable mechanical properties. This study investigates the mechanical performance of multi-layered PVA-C constructs fabricated via sub-zero extrusion-based three-dimensional (3D) bioprinting. Samples with two, four, and six alternating layers were evaluated to assess the effect of layered architecture on elastic and viscoelastic behaviour. Uniaxial tensile testing revealed that increasing the number of layers led to a moderate reduction in stiffness; for instance, at 20% strain, six-layered constructs showed a significantly lower (p < 0.05) Young’s modulus (36.7 ± 2.5 kPa) compared to two-layered ones (47.3 ± 3.1 kPa). Stress–strain curves exhibited nonlinear characteristics, better captured by quadratic (as opposed to linear) fitting, within the tested strain range (≤40%). Dynamic mechanical analysis demonstrated a frequency-independent storage modulus (E′) across 1–10 Hz, with subtle variations in viscoelastic response linked to the number of layers. Visual inspection confirmed improved print fidelity and hydration retention in thicker constructs. These findings demonstrate that a multi-layered design influences the mechanical profile of PVA-C and suggests potential for functionally graded design strategies to enhance compliance matching and mimic the biomechanics of native vessels in small-diameter vascular grafts. Full article

Transcatheter aortic valve replacement (TAVR) has become a well-established treatment for severe aortic stenosis across all levels of surgical risk. While transfemoral access remains the default approach, complications arising from vascular access—especially in patients with peripheral artery disease (PAD)—pose significant challenges. Hostile vascular access, characterized by narrow vessel diameters, severe calcification, and tortuosity, complicates the procedure and necessitates alternative strategies. Recent advancements, such as intravascular lithotripsy (IVL), have shown promise in managing severely calcified arteries, improving the feasibility of transfemoral TAVR in patients previously considered ineligible. IVL uses pulsatile sonic waves to fragment arterial calcifications, enhancing vessel compliance and facilitating safe device delivery. Studies have demonstrated that IVL-assisted TAVR improves procedural success and reduces complications in patients with PAD. Additionally, orbital atherectomy, an adjunctive therapy targeting both concentric and eccentric calcifications, may complement the management of complex arterial calcification. The Hostile and passage–puncture scores offer valuable risk stratification tools for predicting vascular complications, aiding in better access site selection. Post-procedural echocardiography, particularly femoral artery sonography, may also play a role in detecting vascular complications early, enabling timely intervention. Finally, alternative access sites are increasingly being explored, with emerging data helping to guide the final access site decision. As TAVR continues to expand into lower risk populations, optimizing vascular access strategies remains essential to improving procedural outcomes. This review highlights the importance of preoperative imaging, endovascular techniques, and post-procedural monitoring in overcoming vascular challenges and ensuring successful TAVR outcomes. Full article

Nitric oxide (NO), an endogenous vasodilator, has been proposed as a biomarker for pulmonary hypertension (PH) in humans. NO is synthesized by endothelial nitric oxide synthase (eNOS). Alterations in NO/eNOS have not been studied in dogs with PH. We assessed alterations in NO and eNOS in the blood of dogs with PH (n = 17) and healthy dogs (n = 10) and analyzed their correlations with echocardiographic parameters. The results showed significantly higher plasma NO and serum eNOS levels in dogs with PH compared with healthy dogs. Dogs with PH and ascites (n = 11) had significantly lower plasma NO levels than those without ascites (n = 6) and presented a decreasing eNOS trend. In dogs with PH, plasma NO was positively correlated with left ventricular hemodynamics, right ventricular compliance, and pulmonary distensibility, but was negatively correlated with pulmonary vascular resistance and right cardiac remodeling. Serum eNOS was positively correlated with the main pulmonary artery diameter. Increments in NO/eNOS reflected compensatory responses to cardiovascular changes in PH. These compensations were downward in the advanced stages. Other factors may also impact NO/eNOS compensation. Although the role of NO/eNOS as biomarkers for PH in dogs remains equivocal, they may indicate compensatory consequences of cardiovascular alterations. Full article

Introduction: Vascular aging is associated with a loss of aortic compliance (C_A), which results in increased left ventricular pressure–volume area (PVA), stroke work (SW) and myocardial oxygen consumption (MVO₂). Myocardial efficiency (MyoEff) is derived from the PVA and MVO₂ construct, which includes potential energy (PE). However, the SW/MVO₂ ratio does not include PE and provides a more accurate physiologic measure. Methods: We used a modified computational model (CM) to assess PVA and SW and calculate MVO₂ using a pressure-work index (e MVO₂), to derive MyoEff–PVA and MyoEff–SW metrics. Phase I evaluated five levels of human C_A from normal (N) to stiff (S) at 80 bpm, and Phase II evaluated two levels of C_A (N and S) at three heart rates (60, 100, and 140 bpm). Results: During Phase I, MyoEff–PVA increased from 20.7 to 31.2%, and MyoEff–SW increased from 14.8 to 18.9%. In Phase II, during the N setting coupled with increases in the heart rate, the MyoEff–PVA decreased from 29.4 to 14.8 to 9.5%; the MyoEff–SW also decreased from 22.5 to 10.3 to 5.9%. As expected, during the S setting, MyoEff–PVA decreased from 45.5 to 22.9 to 14.8; a similar effect occurred with the MyoEff–SW, demonstrating a decrease from 29.9 to 13.9 to 7.9%, respectively. Conclusions: The CM provided insights into a simple and clinically relevant calculation for assessing MyoEff. The agreement on the CM metrics aligns with studies conducted previously in the clinical setting. Full article

Background: The number of senior chronic kidney disease (CKD) patients is steadily increasing worldwide. Falls are more frequent in this group than in the general population, and they are associated with a variety of complications ranging from minor (bruises) to severe (fracture, brain injury, or death). The significant burden of comorbidities, particularly cardiovascular disorders, impacts coordination. The aim of the study was to assess coordination disorders in CKD patients in the context of cardiovascular complications and vascular status. Methods: In this prospective study, 132 patients with CKD 2–5, including 40 (30%) hemodialysis patients, were enrolled. The short form physiological profile assessment (S-PPA) was used to assess coordination. Results: During a 2-year follow-up period, 49 individuals experienced 84 falls. The median S-PPA score (Z score) was 3.36. Based on this, we divided our cohort into two groups: a Z score of <3.36 and a Z score of ≥3.36. The groups with high scores (≥3.36) characterized by higher parameters of vessel stiffness, including AIx@75, augmentation pressure, and PWV, experienced considerably greater numbers of falls (41 vs. 8, p < 0.001), CV events (10 vs. 2, p < 0.05), and deaths (14 vs. 0, p < 0.001). Conclusions: Coordination impairments and the associated risk of falls in CKD patients are directly related to cardiovascular diseases and vascular conditions. Lower arterial compliance has been linked with the largest coordination disorder. Visual impairments, especially contrast sensitivity, are an independent risk factor for falls. Full article

Noninvasive blood pressure (NIBP) device performance in dogs may be influenced by extreme pressures and altered systemic vascular resistance (SVR). This study evaluated the agreement of two NIBP devices (HDO and petMAP) with invasive blood pressure (IBP) measurements, compliance with hypertension consensus statement criteria, and their trending ability (TA) across varying blood pressure and SVR ranges in awake and anesthetized dogs. Seven healthy Beagles were studied, with IBP recorded from the dorsal metatarsal artery and NIBP cuffs placed randomly on the front limb, hind limb, or base of the tail. Cardiac output was determined by thermodilution, and the systemic vascular resistance index (SVRI) was calculated by a standard formula. Bland–Altman, concordance rate, and polar plot analyses were used for statistical analysis. A total of 752 and 640 paired measurements were obtained for HDO and petMAP, respectively. Both devices showed good agreement with IBP for mean arterial pressure (MAP) at low blood pressure and the SVRI. At high blood pressure and the SVRI, agreement weakened, with substantial underestimation of systolic arterial pressure (SAP). Both devices demonstrated moderate to good TA for MAP and SAP. Overall, the best agreement was observed for MAP at a low SVRI, while agreement was moderate at hypertension (petMAP) and a high SVRI (petMAP, HDO). Full article

Objectives: This study aims to assess the potential role of the ultrasound (US) monochromatic Superb Microvascular Index (mSMI) to predict malignancy of solid focal lesions, correlating the vascular index (VI) with bioptic histological results. Methods: In this single-center retrospective analysis, patients undergoing percutaneous US-guided biopsy of solid lesions were considered. Biopsy indication was given by a multidisciplinary team evaluation based on clinical radiological data. Exclusion criteria were: unfeasible SMI evaluations due to poor respiratory compliance, locations not appreciable with the SMI, previous antiangiogenetic chemo/immunotherapies, and inconclusive histological reports. The mSMI examination was conducted in order to visualize extremely low-velocity flows with a high resolution and high frame rate; the VI was semi-automatically calculated. All bioptic procedures were performed under sole US guidance using 16G or 18G needles, immediately after mSMI assessment. Results: Forty-four patients were included (mean age: 64 years; 27 males, 17 females). Liver (15/43), kidneys (9/43), and lymph nodes (6/43) were the most frequent targets. At histopathological analysis, 7 lesions were benign and 37 malignant, metastasis being the most represented. The VI calculated in malignant lesions was statistically higher compared to benign lesions (35.45% and 11% in malignant and benign, respectively; p-value 0.013). A threshold VI value of 15.4% was identified to differentiate malignant lesions. The overall diagnostic accuracy of the VI with the mSMI was 0.878, demonstrating a high level of diagnostic accuracy. Conclusions: In this study, the mSMI analysis of solid focal lesions undergoing percutaneous biopsy significantly correlated with histological findings in terms of malignant/benign predictive value, reflecting histological vascular changes in malignant lesions. Full article

This study proposes an innovative mathematical model for assessing microcirculation in patients with diabetic ulcers, using the ankle–brachial index (ABI). The methodology combines Bond Graph (BG) modeling and Particle Swarm Optimization (PSO), enabling a detailed analysis of hemodynamic patterns in a pilot sample of three patients. The results revealed a correlation between ulcer size and reduced ABI values, suggesting that deficits in microcirculation directly impact the severity of lesions. Furthermore, despite variations in ABI values and arterial pressures, all patients exhibited high capillary resistance, indicating difficulties in microcirculatory blood flow. The PSO-optimized parameters for the capillary equivalent circuit were found to be $R_1=89.784\Omega$, $R_2=426.55\Omega$, $L=27.506\mathrm{H}$, and $C=0.00040675\mathrm{F}$, which confirms the presence of high vascular resistance and reduced compliance in the microvascular system of patients with diabetic foot ulcers. This quantitative analysis, made possible through mathematical modeling, is crucial for detecting subtle changes in microcirculatory dynamics, which may not be easily identified through conventional pressure measurements alone. The increased capillary resistance observed may serve as a key indicator of vascular impairment, potentially guiding early intervention strategies and optimizing diabetic ulcer treatment. We acknowledge that the sample size of three patients represents a limitation of the study, but this number was intentionally chosen to allow for a detailed and controlled analysis of the variables involved. Although the findings are promising, additional experimental validations are necessary to confirm the clinical applicability of the model in a larger patient sample, thus solidifying its relevance in clinical practice. Full article

Objectives: This study aimed to examine the effects of endurance and high-intensity resistance training on arterial stiffness and ventricular repolarization in elite athletes. Methods: A total of 50 male athletes from different sports disciplines (volleyball, football, judo, and wrestling) and a sedentary group of 30 males participated in this study. Data collected from all participants included age, height, body weight, cardiovascular hemodynamic parameters, arterial stiffness parameters, and ECG measurements. Results: There was no significant age difference between the athlete group (20.42 ± 1.903 years) and the control group (20.97 ± 1.771 years) (p > 0.05). However, body mass index (BMI) values in the control group (24.83 ± 2.22 kg/m²) were significantly different from those in the athlete group (22.39 ± 2.663 kg/m²) (p < 0.05). Significant differences were found between the athlete and control groups in QT dispersion, systolic blood pressure, pulse pressure, and central pulse pressure values (p < 0.05), while similar results were obtained for arterial stiffness parameters (p > 0.05). Conclusions: The lack of a difference in pulse wave velocity and augmentation index (AIx) values between the athletes and the control group suggests that athletes do not bear additional risks regarding arterial stiffness. However, increased systolic blood pressure, pulse pressure, and central pulse pressure, among the hemodynamic parameters, indicate potential variations in vascular wall compliance and hemodynamic responses in the cardiovascular system. The increase in QT dispersion suggests that athletes may exhibit a heterogeneous repolarization process and an elevated risk of ventricular arrhythmias compared to the general population. Full article

Background/Objectives: Surgical site infections are a serious public health concern, representing a significant burden on healthcare systems and society. Their occurrence is influenced by several factors, including patient demographics, healthcare facilities and the specific circumstances surrounding surgery. The use of prophylactic antibiotics in this context carries both potential benefits and risks. The aim of this study is to investigate potential risk factors that may adversely affect the development of SSIs, as well as to assess the appropriateness and adherence to perioperative antibiotic prophylaxis. Methods: This observational study was conducted from October 2023 to October 2024 at the University Hospital of Messina, Italy, a hospital performing both thoracic and vascular surgery. Data were collected using a questionnaire regarding socio-demographic data, risk factors, clinical and surgical data and details regarding the administration of antibiotics. Results: This study included 117 patients with an average age of 63 ± 12.36 SD years, 70.9% from the Thoracic Surgery Unit and 29.1% from the Vascular Surgery Unit. The most administered antibiotic was cefazolin, and antibiotic administration time was in compliance with the guidelines. Conclusions: Our data show that the implementation of evidence-based guidelines, healthcare professionals’ education and correct antibiotic use can reduce the burden of SSIs by improving patient care. Full article

Objective: The study aimed to assess the potential impacts of mean arterial pressure (MAP) and its determinants (cardiac output and systemic vascular resistance) on diabetic nephropathy (DNP)-associated impaired aortic function. Methods: This multi-ethnic study included 115 chronic kidney disease (CKD) patients (67 non-dialysis and 48 dialysis). Six aortic function measures were evaluated by SpygmoCor. The stroke volume was determined by echocardiography. Results: Hypertensive nephropathy (HNP) (53.9%), DNP (32.2%), glomerulonephritis (19.1%), and HIV-associated nephropathy (7.8%) composed the major CKD etiologies. Concurrent HNP and DNP were present in 31.1% of the patients. Participants with compared with those without concurrent HNP and DNP experienced more frequent established cardiovascular disease (43.2% versus 14.9%, p = 0.01), a faster pulse wave velocity (p = 0.001), and smaller total arterial compliance as an indicator of proximal aortic stiffness (p = 0.03). DNP was associated with each aortic function measure (p < 0.001–0.02) independent of potential confounders and MAP, as well as its determinants. HNP was not related to aortic function (p > 0.05 for all relationships). MAP and its determinants did not mediate the potential impact of DNP on aortic function (−4.1–6.4% contribution). Covariates that were associated with impaired aortic function measures included MAP and its determinants (p < 0.001–0.01). Conclusions: Mean or distending arterial pressure and its determinants were associated with impaired aortic function in the overall CKD population. However, these hemodynamic factors did not mediate DNP-associated impaired aortic function. Our results suggest that blood pressure lowering can be anticipated to improve impaired aortic function in the overall CKD population but not when it is solely induced by DNP. Full article

Background: Dialysis-associated events such as bloodstream infections represent serious complications for hemodialysis patients, with the potential to increase morbidity and mortality. Aims: To assess the impact of implementing a comprehensive bundle of evidence-based practice on reducing dialysis event rates among catheter dialysis patients at Prince Mansour Military Hospital Dialysis Center. Participants and Methods: The study enrolled 111 hemodialysis participants. A comprehensive dialysis event prevention bundle consisting of 6 key components was implemented. Results: Implementation of the dialysis event prevention bundle showed a significant decrease in IV antimicrobial start (p = 0.003), positive blood culture (p = 0.039), and inflammation at the vascular access site eliminated (p = 0.004). There was a positive correlation between IV antimicrobial start and both patients’ age (p = 0.005) and the permanent catheter site (p = 0.002). Positive blood culture was significantly correlated with comorbidities (p = 0.000) and patients’ age (p = 0.320). A positive correlation between pus, redness, or increased swelling at the vascular access site with comorbidities (p = 0.034), patients’ age (p = 0.021), and the permanent catheter site (p = 0.002) was observed. Staff compliance with the dialysis event prevention bundle components has improved regarding hemodialysis catheter disconnection, catheter exit site care, and routine disinfection. Conclusions: Implementation of a comprehensive dialysis event prevention bundle can effectively reduce dialysis event rates and enhance patient safety. Full article

Background: The generation and perfusion of complex vascularized tissues in vitro requires sophisticated perfusion techniques. For multiscale arteriovenous networks, not only the arterial, but also the venous, biomechanical and biochemical conditions that physiologically exist in the human body must be accurately emulated. For this, we here present a modular arteriovenous perfusion system for the in vitro culture of a multi-scale bioartificial vascular network. Methods: The custom-built perfusion system consisted of two circuits: in the arterial circuit, physiological arterial biomechanical and biochemical conditions were simulated using a modular set-up with a pulsatile peristaltic pump, compliance chambers, and resistors. In the venous circuit, venous conditions were emulated accordingly. In the center of the system, a bioartificial multi-scale vascularized fibrin-based tissue was perfused by both circuits simultaneously under biomimetic arteriovenous conditions. Culture conditions were monitored continuously using a multi-sensor monitoring system. Results: The physiological arterial and venous pressure- and flow-curves, as well as the microvascular arteriovenous oxygen partial pressure gradient, were accurately emulated in the perfusion system. The multi-sensor monitoring system facilitated live monitoring of the respective parameters and data-logging. In a proof-of-concept experiment, vascularized three-dimensional fibrin tissues showed sustained cell viability and homogenous microvessel formation after culture in the perfusion system. Conclusions: The arteriovenous perfusion system facilitated the in vitro culture of a multiscale vascularized tissue under physiological pressure-, flow-, and oxygen-gradient conditions. With that, it presents a promising technique for the in vitro generation and culture of complex large-scale vascularized tissues. Full article

The risk of developing cardiovascular disease (CVD) escalates in women during menopause, which is associated with increased vascular endothelial dysfunction, arterial stiffness, and vascular remodeling. Meanwhile, curcumin has been demonstrated to enhance vascular function and structure in various studies. Therefore, this study systematically reviewed the recent literature regarding the potential role of curcumin in modulating vascular function and structure during menopause. The Ovid MEDLINE, PubMed, Scopus, and Web of Science electronic databases were searched to identify relevant articles. Clinical and preclinical studies involving menopausal women and postmenopausal animal models with outcomes related to vascular function or structure were included. After thorough screening, seven articles were selected for data extraction, comprising three animal studies and four clinical trials. The findings from this review suggested that curcumin has beneficial effects on vascular function and structure during menopause by addressing endothelial function, arterial compliance, hemodynamic parameters, and the formation of atherosclerotic lesions. Therefore, curcumin has the potential to be utilized as a supplement to enhance vascular health in menopausal women. However, larger-scale clinical trials employing gold-standard techniques to evaluate vascular health in menopausal women are necessary to validate the preliminary results obtained from small-scale randomized clinical trials involving curcumin supplementation (INPLASY, INPLASY202430043). Full article