13 research outputs found

    Towards variable impedance assembly: The VSA peg-in-hole

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    This paper shows how an accurate peg-in-hole assembly task can be easily achieved with nothing but cheap position sensors when resourcing to Variable Impedance Actu-ators (VIA). We present the use of a low-cost Variable Stiffness Torso platform, that consists of two 4-DOF non-planar VSA manipulators, for a peg-in-hole assembly task using both arms. One arm holds the peg and the other holds the hole. The task is accomplished without any force measurement and without calling for parallel-manipulator control techniques, exploiting the intrinsic mechanical elasticity of the actuator units. Indeed, a simple position control scheme is required. Simulations and experimental results are reported

    Deep phenotype characterization of hypertensive response to exercise: implications on functional capacity and prognosis across the heart failure spectrum

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    Aims: Limited evidence is available regarding the role of hypertensive response to exercise (HRE) in heart failure (HF). We evaluated the systolic blood pressure (SBP) to workload slope during exercise across the HF spectrum, investigating haemodynamic and prognostic correlates of HRE. Methods and results: We prospectively enrolled 369 patients with HF Stage C (143 had preserved [HFpEF], and 226 reduced [HFrEF] ejection fraction), 201 subjects at risk of developing HF (HF Stages A-B), and 58 healthy controls. We performed a combined cardiopulmonary exercise stress echocardiography testing. We defined HRE as the highest sex-specific SBP/workload slope tertile in each HF stage. Median SBP/workload slope was 0.53 mmHg/W (interquartile range 0.36-0.72); the slope was 39% steeper in women than men (p < 0.0001). After adjusting for age and sex, SBP/workload slope in HFrEF (0.47, 0.30-0.63) was similar to controls (0.43, 0.35-0.57) but significantly lower than Stages A-B (0.61, 0.47-0.75) and HFpEF (0.63, 0.42-0.86). Patients with HRE showed significantly lower peak oxygen consumption and peripheral oxygen extraction. After a median follow-up of 16 months, HRE was independently associated with adverse outcomes (all-cause mortality and hospitalization for cardiovascular reasons: hazard ratio 2.05, 95% confidence interval 1.81-5.18), while rest and peak SBP were not. Kaplan-Meier analysis confirmed a worse survival probability in Stages A-B (p = 0.005) and HFpEF (p < 0.001), but not HFrEF. Conclusion: A steeper SBP/workload slope is associated with impaired functional capacity across the HF spectrum and could be a more sensitive predictor of adverse events than absolute SBP values, mainly in patients in Stages A-B and HFpEF

    Ventricular-Arterial Coupling Derived From Proximal Aortic Stiffness and Aerobic Capacity Across the Heart Failure Spectrum

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    Objectives: This study aimed to evaluate ventricular-arterial coupling (VAC) across the spectrum of heart failure (HF). Background: VAC can be evaluated as the ratio between arterial stiffness (pulsed wave velocity [PWV]) and myocardial deformation (global longitudinal strain [GLS]). Methods: The authors introduced a Doppler-derived, single-beat technique to estimate aortic arch PWV (aa-PWV) in addition to tonometry-derived carotid-femoral PWV (cf-PWV). They measured PWVs and GLS in 155 healthy controls, 75 subjects at risk of developing HF (American College of Cardiology/American Heart Association stage A-B) and 236 patients in stage C heart failure with preserved ejection fraction (HFpEF) (n = 104) or heart failure with reduced ejection fraction (HFrEF) (n = 132). They evaluated peak oxygen consumption and peripheral extraction using combined cardiopulmonary-echocardiography exercise stress. Results: aa-PWV was obtainable in all subjects and significantly lower than cf-PWV in all subgroups (P &lt; 0.01). PWVs were directly related and increased with age (all P &lt; 0.0001). cf-PWV/GLS was similarly compromised in HFrEF (1.09 ± 0.35) and HFpEF (1.05 ± 0.21), whereas aa-PWV/GLS was more impaired in HFpEF (0.70 ± 0.10) than HFrEF (0.61 ± 0.14; P &lt; 0.01). Stage A-B had values of cf-PWV/GLS and aa-PWV/GLS (0.67 ± 0.27 and 0.48 ± 0.14, respectively) higher than controls (0.46 ± 0.11 and 0.39 ± 0.10, respectively) but lower than stage C (all P &lt; 0.01). Peak arteriovenous oxygen difference (AVO2diff) was inversely related with cf-PWV/GLS and aa-PWV/GLS (all P &lt; 0.01). Although cf-PWV/GLS and aa-PWV/GLS independently predicted peak VO2 in the overall population (adjusted R2 = 0.33 and R2= 0.36; all P &lt; 0.0001), only aa-PWV/GLS was independently associated with flow reserve during exercise (R2 = 0.52; P &lt; 0.0001). Conclusions: Abnormal VAC is directly correlated with greater severity of HF and worse functional capacity. HFpEF shows a worse VAC than HFrEF when expressed by aa-PWV/GLS

    Ventricular-Arterial Coupling Derived From Proximal Aortic Stiffness and Aerobic Capacity Across the Heart Failure Spectrum

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    Background: Ventricular-arterial coupling (VAC) can be evaluated as the ratio between arterial stiffness (pulsed wave velocity [PWV]) and myocardial deformation (global longitudinal strain [GLS]). Objectives: This study aimed to evaluate VAC across the spectrum of heart failure (HF). Methods: The authors introduced a Doppler-derived, single-beat technique to estimate aortic arch PWV (aa-PWV) in addition to tonometry-derived carotid-femoral PWV (cf-PWV). They measured PWVs and GLS in 155 healthy controls, 75 subjects at risk of developing HF (American College of Cardiology/American Heart Association stage A-B) and 236 patients in stage C heart failure with preserved ejection fraction (HFpEF) (n = 104) or heart failure with reduced ejection fraction (HFrEF) (n = 132). They evaluated peak oxygen consumption and peripheral extraction using combined cardiopulmonary-echocardiography exercise stress. Results: aa-PWV was obtainable in all subjects and significantly lower than cf-PWV in all subgroups (P < 0.01). PWVs were directly related and increased with age (all P < 0.0001). cf-PWV/GLS was similarly compromised in HFrEF (1.09 ± 0.35) and HFpEF (1.05 ± 0.21), whereas aa-PWV/GLS was more impaired in HFpEF (0.70 ± 0.10) than HFrEF (0.61 ± 0.14; P < 0.01). Stage A-B had values of cf-PWV/GLS and aa-PWV/GLS (0.67 ± 0.27 and 0.48 ± 0.14, respectively) higher than controls (0.46 ± 0.11 and 0.39 ± 0.10, respectively) but lower than stage C (all P < 0.01). Peak arteriovenous oxygen difference (AVO2diff) was inversely related with cf-PWV/GLS and aa-PWV/GLS (all P < 0.01). Although cf-PWV/GLS and aa-PWV/GLS independently predicted peak VO2 in the overall population (adjusted R2 = 0.33 and R2= 0.36; all P < 0.0001), only aa-PWV/GLS was independently associated with flow reserve during exercise (R2 = 0.52; P < 0.0001). Conclusions: Abnormal VAC is directly correlated with greater severity of HF and worse functional capacity. HFpEF shows a worse VAC than HFrEF when expressed by aa-PWV/GLS. Keywords: exercise capacity; heart failure; heart failure with preserved ejection fraction (HFpEF); pulsed wave velocity; ventricular-arterial coupling (VAC)

    The SUNRISE Summer School: an innovative learning-by-doing experience for the documentation of archaeological heritage

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    The first edition of the SUNRISE (Seashore and UNderwater documentation of aRchaeological herItage palimpSests and Environment) summer school was carried out in Marina di Ragusa in Sicily (Italy) from 3rd to 9th September 2022. It was jointly organized by Politecnico di Torino, IUAV, University of Sassari, FBK, University of Udine and the University of Modena and Reggio Emilia with the support of SIFET, ISPRS Student Consortium, private companies (Images, Microgeo, Stonex, Leica and Geomax) and the municipality of Santa Croce Camerina.The five days of summer school were attended by 20 students from Europe, Asia and USA. After the first day of lectures focused on the theoretical basis of surveying, photogrammetry, LiDAR, and SLAM, the field activities took place in a submerged and terrestrial scenario. The underwater surveying involved a submerged amphora, and the terrestrial activity was focused on the Arab bath of Mezzagnone, a 6th-century AD building that has been fully preserved until today. The paper deal with this experience and underline the followed approach. Finally some results achieved by the students are reported

    Cardiometabolic Phenotyping in Heart Failure: Differences between Patients with Reduced vs. Preserved Ejection Fraction

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    Aims. We explored multiple cardiometabolic patterns, including inflammatory and congestive pathways, in patients with heart failure (HF). Methods and Results. We enrolled 270 HF patients with reduced (n = 96) and preserved (≥50%, HFpEF; n = 174) ejection fraction. In HFpEF, glycated hemoglobin (Hb1Ac) seemed to be relevant in its relationship with inflammation as Hb1Ac positively correlated with high-sensitivity C-reactive protein (hs-CRP; Spearman’s rank correlation coefficient ρ = 0.180, p p p p p p < 0.05). Conclusion. In HF patients, HFpEF and HFrEF phenotypes are characterized by different cardiometabolic indices related to distinct inflammatory and congestive pathways. Patients with HFpEF showed an important relationship between inflammatory and cardiometabolic parameters. Conversely, in HFrEF, there is a significant relationship between congestion and inflammation, while cardiometabolism appears not to influence inflammation, instead affecting sympathetic hyperactivation

    Bio-Humoral and Non-Invasive Haemodynamic Correlates of Renal Venous Flow Patterns across the Heart Failure Spectrum

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    Background: We evaluated the bio-humoral and non-invasive haemodynamic correlates of renal congestion evaluated by Doppler renal venous flow (RVF) across the heart failure (HF) spectrum, from asymptomatic subjects with cardiovascular risk factors (Stage A) and structural heart disease (Stage B) to patients with clinically overt HF (Stage C). Methods: Ultrasound evaluation, including echocardiography, lung ultrasound and RVF, along with blood and urine sampling, was performed in 304 patients. Results: Continuous RVF was observed in 230 patients (76%), while discontinuous RVF (dRVF) was observed in 74 (24%): 39 patients had pulsatile RVF, 18 had biphasic RVF and 17 had monophasic RVF. Stage C HF was significantly more common among patients with dRVF. Monophasic RVF was associated with worse renal function and a higher urinary albumin-to-creatinine ratio (uACR). After adjusting for hypertension, diabetes mellitus, the presence of Stage C HF and serum creatinine levels, worsening RVF patterns were associated with higher NT-proBNP levels, worse right ventricular-arterial coupling, larger inferior vena cava and higher echo-derived pulmonary artery wedge pressure. This trend was confirmed when only patients with HF Stage C were analysed after adjusting for the left ventricle ejection fraction (LVEF). Conclusion: Abnormal RVF is common across the HF spectrum. Worsening RVF patterns are independently associated with increased congestion, worse non-invasive haemodynamics and impaired RV-arterial coupling. RVF evaluation could refine prognostic stratification across the HF spectrum, irrespective of LVEF

    Arterial Hypertension and Cardiopulmonary Function: The Value of a Combined Cardiopulmonary and Echocardiography Stress Test

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    Arterial hypertension (AH) is a global burden and the leading risk factor for mortality worldwide. Haemodynamic abnormalities, longstanding neurohormonal and inflammatory activation, which are commonly observed in patients with AH, promote cardiac structural remodeling ultimately leading to heart failure (HF) if blood pressure values remain uncontrolled. While several epidemiological studies have confirmed the strong link between AH and HF, the pathophysiological processes underlying this transition remain largely unclear. The combined cardiopulmonary-echocardiography stress test (CPET-ESE) represents a precious non-invasive aid to detect alterations in patients at the earliest stages of HF. The opportunity to study the response of the cardiovascular system to exercise, and to differentiate central from peripheral cardiovascular maladaptations, makes the CPET-ESE an ideal technique to gain insights into the mechanisms involved in the transition from AH to HF, by recognizing alterations that might be silent at rest but influence the response to exercise. Identifications of these subclinical alterations might allow for a better risk stratification in hypertensive patients, facilitating the recognition of those at higher risk of evolution towards established HF. This may also lead to the development of novel preventive strategies and help tailor medical treatment. The purpose of this review is to summarise the potential advantages of using CPET-ESE in the characterisation of hypertensive patients in the cardiovascular continuum

    Haemodynamic forces predicting remodelling and outcome in patients with heart failure treated with sacubitril/valsartan

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    Abstract Aims A novel tool for the evaluation of left ventricular (LV) systo‐diastolic function through echo‐derived haemodynamic forces (HDFs) has been recently proposed. The present study aimed to assess the predictive value of HDFs on (i) 6 month treatment response to sacubitril/valsartan in heart failure with reduced ejection fraction (HFrEF) patients and (ii) cardiovascular events. Methods and results Eighty‐nine consecutive HFrEF patients [70% males, 65 ± 9 years, LV ejection fraction (LVEF) 27 ± 7%] initiating sacubitril/valsartan underwent clinical, laboratory, ultrasound and cardiopulmonary exercise testing evaluations. Patients experiencing no adverse events and showing ≥50% reduction in plasma N‐terminal pro‐B‐type natriuretic peptide and/or ≥10% LVEF increase over 6 months were considered responders. Patients were followed up for the composite endpoint of HF‐related hospitalisation, atrial fibrillation and cardiovascular death. Forty‐five (51%) patients were responders. Among baseline variables, only HDF‐derived whole cardiac cycle LV strength (wLVS) was higher in responders (4.4 ± 1.3 vs. 3.6 ± 1.2; p = 0.01). wLVS was also the only independent predictor of sacubitril/valsartan response at multivariable logistic regression analysis [odds ratio 1.36; 95% confidence interval (CI) 1.10–1.67], with good accuracy at receiver operating characteristic (ROC) analysis [optimal cutpoint: ≥3.7%; area under the curve (AUC) = 0.736]. During a 33 month (23–41) median follow‐up, a wLVS increase after 6 months (ΔwLVS) showed a high discrimination ability at time‐dependent ROC analysis (optimal cut‐off: ≥0.5%; AUC = 0.811), stratified prognosis (log‐rank p < 0.0001) and remained an independent predictor for the composite endpoint (hazard ratio 0.76; 95% CI 0.61–0.95; p < 0.01), after adjusting for clinical and instrumental variables. Conclusions HDF analysis predicts sacubitril/valsartan response and might optimise decision‐making in HFrEF patients
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