Since its beginnings, cardiovascular (CV) medicine has relied on professionals' judgment to diagnose various types of studies carried out on patients. Today, with the support of technologies such as machine learning (ML) and artificial neural networks, medical professionals can automate, speed up or improve their diagnoses by obtaining complementary information on the detection of diseases and CV conditions. This work proposes an online platform based on ML methods, applied to the analysis of echocardiographic recordings. The aim is to obtain dynamic measurements of an individual left ventricle behavior, and contributing to the detection of different types of heart conditions, thereby improving diagnostic precision.

Introduction: The left ventricle (LV) serves as the primary source of mechanical energy in circulation, subsequently converted into kinetic energy throughout the arterial system (AS). Analyzing the specific area within an LV pressure-volume (PV) loop helps characterize the function of the cardiac pump. Simultaneously, the AS functions as a blood reservoir, receiving the blood ejected by the LV. The enclosed area in the AS PV-loop is linked to an energy dissipation process (where not all pressure work is regained), attributed to the viscous function of smooth muscle cells. Objective: The main objective of this work was to investigate wall energy dissipation in the vascular bed in terms of LV and AS PV-loop evaluation, to determine if different types of training could lead to differentiated levels of wall energy dissipation. The ‘coupling concept’ is proposed to be conceived from LV and AS loop energy interaction, quantified by a ‘ventricular-arterial damping factor’ (VADF). Material and Methods: Data from subjects with different kinds of training (soccer players and ballet dancers) were collected noninvasively and compared with a control group of untrained individuals to analyze the differentiating characteristics of the subjects, especially in terms of Stroke Work Dissipation (WDIS). To this end, a lumped parameters Windkessel (WK) model was proposed for the assessment of LV and AS loops, through an interactive process. Changes in wall energy dissipation were observed under training routines. Both soccer players and ballet dancers showed increased WDIS and VADF compared to the untrained individuals (p<0.05). However, elastic work (WEL), defined as the difference between LV stroke work and WDIS, was found to remain constant in ballet dancers, unlike in soccer players. Conclusion: The WK model enabled the simulation of the interaction between LV and AS based on a ventricular-arterial coupling framework. The findings suggest that higher WDIS values, together with the preservation of WEL, may indicate an enhanced protective effect by vascular smooth muscle cells and other wall components, involved in the AS dissipation phenomenon.

Many studies found that increased arterial stiffness is significantly associated with the presence and progression of Coronary Calcium Score (CCS). However, none so far have used machine learning algorithms to improve their value. Therefore, this study aims to evaluate the association between carotid-femoral Pulse Wave Velocity (cfPWV) and CCS score through computational clustering. We conducted a retrospective cross-sectional study using data from a cardiovascular risk screening program that included 377 participants. We used an unsupervised clustering algorithm using age, weight, height, blood pressure, heart rate, and cfPWV as input variables. Differences between cluster groups were analyzed through Chi-square and T-student tests. The association between (i) cfPWV and age groups, (ii) log (CCS) and age groups, and (iii) cfPWV and log(CCS) were addressed through linear regression analysis. Clusters were labeled post hoc based on cardiovascular risk. A “higher-risk group” had significantly higher left (0.76 vs. 0.70 mm, P < 0.001) and right (0.71 vs. 0.66 mm, P = 0.003) intima-media thickness, CCS (42 vs. 4 Agatston units, P = 0.012), and ascending (3.40 vs. 3.20 cm, P < 0.001) and descending (2.60 vs. 2.37 cm, P < 0.001) aorta diameters. Association with age appeared linear for cfPWV and exponential for log (CCS). The progression of the log (CCS) and cfPWV through age groups was steeper in the “higher-risk group” than in the “lower-risk group”. cfPWV strongly correlated with CCS, and CCS progression over cfPWV differed among clusters. This finding could improve PWV as a “gate-keeper” of CCS testing and potentially enhance cardiovascular risk stratification.

INTRODUCTION: Arterial wall viscosity is a source of energy dissipation that takes place during mechanical transduction. In our previous studies, a "global" damping effect in endurance training athletes was introduced, verifying that endurance-athletes dissipate greater pulsatile energy in the circulation compared with healthy untrained subjects. OBJECTIVE: To investigate the wall energy dissipation in the vascular bed for each beat and within the conceptual framework of ventricular-arterial coupling, in order to elucidate if different types of training could lead to differentiated levels of cardiovascular energy dissipation. MATERIALS AND METHODS: Data from subjects with different kinds of training (soccer players and ballet dancers) have been collected noninvasively and compared with a control group of untrained individuals to analyse the differentiating characteristics of the subjects, especially in terms of Stroke Work Dissipation (WDIS). RESULTS: In the endurance-trained individuals, an enhanced WDIS has been observed compared to the untrained individuals (p<0.05). However, non-significant differences were found regarding ballet-dancers group. CONCLUSION: Changes in wall energy dissipation are developed under high intensity endurance training routines.

INTRODUCTION:Left ventricular (LV) interaction with the arterial system (arterial-ventricular coupling, AVC) is a central determinant of cardiovascular performance and cardiac energetics. Stress Echocardiography (SE) constitutes a valuable clinical tool in both diagnosis and risk stratification of patients with suspected and established coronary artery disease. Cluster Analysis (CA), an unsupervised Machine Learning technique, defines an exploratory statistical method which can be used to uncover natural groups within data.OBJECTIVE:To evaluate the capacity of CA to identify uncoupled groups with ischemic condition based on SE baseline information.MATERIAL AND METHODS:CA was applied to SE data acquired at baseline and peak exercise (PE) conditions. Obtained clusters were evaluated in terms of coupling conditions and LV wall motility alterations.RESULTS:Inter cluster significant AVC differences were obtained in terms of baseline data and changes in wall motility, confirmed by CA applied to PE data.CONCLUSION:AVC impairment was evidenced in both normal and ischemic subjects by applying CA.

INTRODUCTION: Athletes training is often associated with morphological changes in the heart. In this sense, the ventricular pressure-volume (PV) relation provides a complete characterization of cardiac pump performance. Regarding the arterial system (AS), arterial wall viscosity is a source of energy dissipation, that takes place during mechanical transduction. Left ventricular stroke work (SW) constitutes the useful fraction of ventricular energy that is delivered to the AS. OBJECTIVE: Left ventricular PV-loops were evaluated in terms of AS viscous property, by means of the interaction of two SW components (Stroke Work Damping Ratio, SWDR), both in untrained and trained subjects. MATERIAL AND METHODS: Fourteen healthy individuals (seven trained) were non-invasively evaluated in terms of echocardiographic and aortic pressure measurements. RESULTS: SWDR was observed to be increased in trained subjects. CONCLUSION: SWDR was evaluated in trained individuals, being increased in comparison with the non-trained group. This effect is a consequence of a significant increase of SWD, which could be related with the viscous mechanical property of AS.

INTRODUCTION: Arterial-ventricular coupling (AVC) has been recognized as a key determinant of global cardiovascular performance. Diastolic dysfunction (DD) occurs when inadequate filling of the ventricles is related to an abnormal elevation of intracardiac filling pressures. In some cases, DD is evidenced during cardiac stress, provoked by exercise. OBJECTIVE: To evaluate AVC in individuals with stress evidenced DD, in relation to controls. MATERIALS AND METHODS: Stress echocardiography was applied to assess cardiac function during exercise. Arterial-ventricular coupling was evaluated, based on the assessment of left ventricular and arterial elastances. RESULTS: AVC showed a significant difference at peak exercise compared to controls, basically due to a loss of cardiac contractility. CONCLUSION: The manifestation of AVC coupling imbalance could act as a complementary parameter to support the diagnosis of DD.

INTRODUCTION:Cirrhosis is associated with changes in the cardiovascular system, where the circulatory dysfunction is compensated by the development of a hyperdynamic circulation. Endothelial function can be understood as the endothelium capability to release Nitric Oxide (NO) where an impairment in the normal development of this process constitutes a main step in the genesis and progression of atherosclerosis, a major cause of cardiovascular events. In recent years, non-invasive measurements have gained attention, due to the potential complications associated to invasive procedures.OBJECTIVE:To evaluate endothelial function (EF) in patients with cirrhosis, in different stages of the disease, complemented with hemodynamic measurements.METHODS:Individuals were divided in three age groups, according to the severity of their disease. EF was assessed by using the flow mediated dilation technique (FMD), jointly with noninvasive determination of cardiac output (CO), total peripheral resistance (TPR) and arterial compliance (AC).RESULTS:TPR showed a decrease in advanced severity while AC had an increase. Particularly, EF was found to be higher in CHC group, decreasing in CHB and more pronounceably in CHA. Concomitantly, an inverse behavior was observed regarding CO evolution.CONCLUSION:EF was noninvasively evaluated in cirrhosis, in terms of the progression of the disease. Hyperdynamic states in the more advanced condition were accompanied by a higher vascular reactivity, probably associated with higher peripheral NO release and increased AC.

Introduction: Hypertrophic cardiomyopathy (HCM) is associated with altered hemodynamics in the left ventricular outflow tract and tissue abnormalities. Exercise testing has become an integral and powerful tool for the noninvasive evaluation of HCM and, in some patients, it could define a treatment strategy. Objective: To model the hemodynamic alterations during exercise in healthy and HCM patients, obtained by noninvasive methods. Methods: Cardiac output (CO), heart rate (HR), arterial blood pressure (ABP) and Total Peripheral Resistance (TPR) were assessed during exercise. The evaluation included a curve-fitting approach (sigmoidal model) that allowed a quantitative comparison of CO profiles. Results: When compared to controls, patients with HCM showed reduced peak exercise cardiac output and demonstrated high peripheral resistance during exercise. Analysis of modeled CO curves revealed a higher maximum rate of recovery in healthy individuals than in HCM patients. Conclusion: The application of the sigmoidal model showed to be efficient in the characterization of CO dynamics for the different studied groups.

Introduction: Measurement of hemodynamic parameters constitutes an important tool in the management of patients with cirrhosis. In recent years, non-invasive measurements have gain attention, due to the potential complications associated to invasive procedures. Objective: To characterize the hemodynamic alterations of cirrhosis in young and adult subjects, through a three element windkessel (WK3e). Methods: Individuals were divided in three age groups: Young Healthy group (control, CG), Young Cirrhotic Group (YCG) and Adult Cirrhotic Group (ACG). A Finapres® Nova device was used to obtain cardiac output (CO), heart rate and arterial blood pressure. Systemic arterial compliance (C), peripheral resistance (R) and characteristic impedance (Zc) were also provided. Effective arterial elastance (Ea), left ventricular work (LVW), input impedance, efficiency and model cutoff frequency (WK CF ) were assessed based on the provided data. Results: CO resulted to be higher in ACG than in CG and YGC. LVW, C and WKcf showed an increase, while R and Ea showed a decrease. However, this behavior was not observed in YCG. Conclusion: Cirrhosis was properly modeled in young and adult subjects in terms of non-invasive measurements and a WK3e.

The aims of our work were to determine normal aging rates for structural and functional arterial parameters in healthy children, adolescents, and young adults and to identify gender-related differences in these aging rates. Methods. 161 subjects (mean: 15 years (range: 4–28 years), 69 females) were studied. Subjects included had no congenital or chronic diseases, nor had they been previously exposed to traditional cardiovascular risk factors. Arterial parameters assessed were (1) central blood pressure (BP) and aortic pulse wave analysis, (2) arterial local (pressure-strain elastic modulus) and regional (pulse wave velocity, PWV) stiffness, and (3) arterial diameters and carotid intima-media thickness (CIMT). Simple linear regression models (age as the independent variable) were obtained for all the parameters and the resulting rates of change were compared between genders. Results. No gender-related differences were found in mean values of arterial structural and functional parameters in prepubertal ages (4–8 years), but they started to appear at ~15 years. Boys showed a greater rate of change for central systolic BP, central pulse pressure, CIMT, and carotid-femoral PWV. Conclusion. Gender-related differences in arterial characteristics of adults can be explained on the basis of different growing-related patterns between boys and girls, with no existing differences in prepubertal ages.

Introduction: In recent years, peripheral arterial tonometry (PAT, a non-invasive and reproducible technique) has gained considerable interest. In this sense, arterial capacity to react to vasoactive stimulus (induced by reactive hyperemia) is known as vascular reactivity (VR). Objective: Post ischemic beat to beat VR characterization was performed based on PAT measurements. Methods: Systolic Blood Pressure (SBP) and Augmentation index (AIx) variations were modeled, as a response to flow stimulus. Results: Obtained R 2 values were around 70% for VR while, to a lesser degree, AIx fit was about 50% Conclusion: Beat to Beat VR was described in terms of SBP and AIx behavior. Further studies are needed to determine the clinical usefulness of the proposed indicators.

Endothelial cells are involved in the local regulation of blood flow and vessel diameter, playing multiple roles, both in health and disease. Changes in endothelial functions are defined as endothelial dysfunction (ED). In vivo non-invasive evaluation of ED and vascular reactivity can be performed by means of different approaches, where Flow Mediated Dilation (FMD) and Peripheral Arterial Tonometry (PAT) measurements (in terms of a post occlusive reactive hyperemia maneuver, PORH) are considered the most relevant. The main objective of this study was to perform the evaluation of FMD and PAT simultaneously, in healthy men and women, in order to characterize the pressure and diameter time profiles during PORH. Different exponential functions were fitted to systolic pressure and diameter responses, suggesting a differentiated vascular behavior between genders.

Introduction. Flow-mediated dilation (FMD), low flow-mediated constriction (L-FMC), and reactive hyperemia-related changes in carotid-to-radial pulse wave velocity (ΔPWVcr%) could offer complementary information about both “recruitability” and “resting” endothelial function (EF). Carotid-to-femoral pulse wave velocity (PWVcf) and pulse wave analysis-derived parameters (i.e., AIx@75) are the gold standard methods for noninvasive evaluation of aortic stiffness and central hemodynamics. If healthy pregnancy is associated with both changes in resting and recruitable EF, as well as in several arterial parameters, it remains unknown and/or controversial. Objectives. To simultaneously and noninvasively assess in healthy pregnant (HP) and nonpregnant (NP) women central parameters in conjunction with “basal and recruitable” EF, employing new complementary approaches. Methods. HP (n = 11, 34.2 ± 3.3 weeks of gestation) and age- and cardiovascular risk factors-matched NP (n = 22) were included. Aortic blood pressure (BP), AIx@75, PWVcf, common carotid stiffness, and intima-media thickness, as well as FMD, L-FMC, and ΔPWVcr %, were measured. Results. Aortic BP, stiffness, and AIx@75 were reduced in HP. ΔPWVcr% and FMD were enhanced in HP in comparison to NP. No differences were found in L-FMC between groups. Conclusion. HP is associated with reduced aortic stiffness, central BP, wave reflections, and enhanced recruitable, but not resting, EF.

Introduction. An altered endothelial function (EF) could be associated with preeclampsia (PE). However, more specific and complementary analyses are required to confirm this topic. Flow-mediated dilation (FMD), low-flow-mediated constriction (L-FMC), and hyperemic-related changes in carotid-radial pulse wave velocity (PWVcr) offer complementary information about "recruitability" of EF. Objectives. To evaluate, in healthy and hypertensive pregnant women (with and without PE), central arterial parameters in conjunction with "basal and recruitable" EF. Methods. Nonhypertensive (HP) and hypertensive pregnant women (gestational hypertension, GH; preeclampsia, PE) were included. Aortic blood pressure (BP), wave reflection parameters (AIx@75), aortic pulse wave velocity (PWVcf) and PWVcr, and brachial and common carotid stiffness and intima-media thickness were measured. Brachial FMD and L-FMC and hyperemic-related change in PWVcr were measured. Results. Aortic BP and AIx@75 were elevated in PE. PE showed stiffer elastic but not muscular arteries. After cuff deflation, PWVcr decreased in HP, while GH showed a blunted PWVcr response and PE showed a tendency to increase. Maximal FMD and L-FMC were observed in HP followed by GH; PE did not reach significant arterial constriction. Conclusion. Aortic BP and wave reflections as well as elastic arteries stiffness are increased in PE. PE showed both "resting and recruitable" endothelial dysfunctions.

Intro duc ción: el con su mo de co caí na en for ma de clor hi dra to (CC), y es pe cial men te de su pas ta base (PBC), es un pro ble ma sa ni ta rio ma yor, en tre otros fac to res, por su in ci den cia, re per cu sión y fran ja eta ria a la que in vo lu cra. Múl ti ples efec tos car dio vas cu la res han sido des cri tos en aso cia ción con el con su mo de CC, pero el im pac to a cor to/me dia no pla zo del uso cró ni co de CC y PBC en el sis te ma ar te rial en su je tos jó ve nes no se ha es tu dia do. Obje ti vo: de ter mi nar la pre va len cia de cam bios (al te ra cio nes) ar te ria les es truc tu ra les y/o fun cio na les en jó ve nes con su mi do res de co caí na o sus de ri va dos. Ma te rial y mé to do: se in clu ye ron 29 su je tos (27 hom bres; edad me dia/ran go: 29/20-35 años) con cri te rios to xi co ló gi cos de de pen den cia a co caí na, más de dos años de con su mo, y abs ti nen cia me nor a un mes. Se rea li zó eva lua ción clí ni ca y pa ra clí ni ca para cuan ti fi car el ries go car dio vas cu lar glo bal (es co re de ries go de Fra ming ham [EF] para en fer me dad car dio vas cu lar a diez años). Los es tu dios in clu ye ron de ter mi na ción de: 1) pre sen cia de pla cas de ate ro ma ca ro tí deas y es pe sor ín ti ma-me dia ca ro tí deo (EIMC; eco gra fía modo-B co lor y soft wa re es pe cí fi co). 2) Ri gi dez aór ti ca re gio nal (me dian te ve lo ci dad de la onda del pul so, [VOP]). 3) Pre sión de pul so aór ti ca cen tral (to no me tría de apla na mien to). 4) Índi ce to bi llo-bra zo (os ci lo me tría). 5) Reac ti vi dad vas cu lar, fun ción en do te lial, por va so di la ta ción me dia da por flu jo (DMF; eco gra fía modo-B y soft wa re es pe cí fi co). Se de ter mi nó la edad vas cu lar (EV) me dian te aná li sis mul ti pa ra mé tri co. El en ve je ci mien to ar te rial pre coz (EAP) se de fi nió como la di fe ren cia en tre la EV y la edad cro no ló gi ca. Los da tos ob te ni dos se com pa ra ron con va lo res de nor ma li dad (su je tos con trol). Re sul ta dos: de los 29 pa cien tes, 10 fue ron con su mi do res de CC, 3 de PBC y 16 de am bas sus tan cias. El 90% eran fu ma do res de ci ga rri llos (pro me dio de con su mo: 14,4 ci ga rri llos/día). Si bien nin gún pa cien te pre sen tó VOP >10 m/s (pun to de nor ma li dad acep ta do por la So cie dad Eu ro pea de Car dio lo gía), 63,6% tuvo ni ve les de VOP en tre el per cen til (p)50 y el p90 de la po bla ción con trol de re fe ren cia, y 13,6% por en ci ma del p90 de la mis ma po bla ción, in di can do que el 77,2% de los mis mos pre sen ta ron VOP >p50. Res pec to del EIMC, un 8% de los pa cien tes es tu dia dos tuvo ni ve les > 0,9 mm, y 69% ni ve les por en ci ma del p95 de la po bla ción de re fe ren cia, para sexo y edad.. El aná li sis de la fun ción en do te lial mos tró que 13,6% de los pa cien tes no pre sen tó di la ta ción ar te rial (DMF  0%) y 36% pre sen tó DMF  5%. Fi nal men te, el 33% de los pa cien tes pre sen tó ni ve les de pre sión de pul so aór ti ca por en ci ma del ni vel um bral (p95), para sexo y edad. La EA fue de 37,1 ± 8,4 años, in di can do la exis ten cia de un EAP de 8,1 ± 6,2 años (ran go: 3-24 años). Con clu sión: los usua rios de co caí na mos tra ron cam bios sub clí ni cos per ju di cia les a ni vel ar te rial que se aso cian a ma yor ries go car dio vas cu lar. Sus pa rá me tros ar te ria les pre sen ta ron ni ve les com pa ti bles con los exis ten tes en una po bla ción con trol con una edad de 8,1 ± 6,2 años ma yor que la es tu dia da, in di can do que los con su mi do res de CC y PBC po drían pre sen tar “en ve je ci mien to ar te rial pre coz”.

Background: systolic heart failure (SHF) is associated with an increased oxidative stress which may be related with an increased risk of atherosclerosis; but...