Caracterización de pacientes con diferentes niveles de riesgo cardiovascular mediante diagramas de Poincaré

En este trabajo se propone caracterizar la dinámica no-lineal de los sistemas cardíaco, vascular y respiratorio a partir de los diagramas de Poincaré. Se han analizado 46 pacientes con cardiomiopatía isquémica (ICM) o dilatada (DCM), y 35 sujetos sanos. De acuerdo con su fracción de eyección ventricular izquierda (LVEF), los pacientes también fueron clasificados en un grupo de alto riesgo (HR: LVEF = 35%, 30 pacientes) y otro de bajo riesgo (LR: LVEF > 35%, 16 pacientes). A partir de las señales electrocardiográfica, de flujo respiratorio y de presión sanguínea se han obtenido los datos relacionados con el tiempo entre latidos cardíacos (RR), entre valores máximos de presión sistólica (SBP), y la duración del ciclo respiratorio (TTot). Estas series temporales han sido representadas mediante los diagramas de Poincaré, y caracterizadas teniendo en cuenta su desviación a largo plazo (SD1) y su cambio instantáneo (SD2). De acuerdo con los resultados obtenidos, los parámetros de las series cardíaca y de presión sanguínea, relacionados con las diagonales longitudinales y transversales del diagrama de Poincaré, son los que mejor diferencian entre pacientes con HR vs LR. Para la clasificación de pacientes isquémicos vs dilatados, los mejores parámetros se obtuvieron a partir de las series respiratorias y están relacionados con las distancias de la desviación estándar a la línea de identidad. Los cambios en estas relaciones representan una mayor aceleración en la dinámica respiratoria de los pacientes con cardiomiopatía isquémica.Postprint (published version

Assessment of respiratory flow cycle morphology in patients with chronic heart failure

Breathing pattern as periodic breathing (PB) in chronic heart failure (CHF) is associated with poor prognosis and high mortality risk. This work investigates the significance of a number of time domain parameters for characterizing respiratory flow cycle morphology in patients with CHF. Thus, our primary goal is to detect PB pattern and identify patients at higher risk. In addition, differences in respiratory flow cycle morphology between CHF patients (with and without PB) and healthy subjects are studied. Differences between these parameters are assessed by investigating the following three classification issues: CHF patients with PB versus with non-periodic breathing (nPB), CHF patients (both PB and nPB) versus healthy subjects, and nPB patients versus healthy subjects. Twenty-six CHF patients (8/18 with PB/nPB) and 35 healthy subjects are studied. The results show that the maximal expiratory flow interval is shorter and with lower dispersion in CHF patients than in healthy subjects. The flow slopes are much steeper in CHF patients, especially for PB. Both inspiration and expiration durations are reduced in CHF patients, mostly for PB. Using the classification and regression tree technique, the most discriminant parameters are selected. For signals shorter than 1 min, the time domain parameters produce better results than the spectral parameters, with accuracies for each classification of 82/78, 89/85, and 91/89 %, respectively. It is concluded that morphologic analysis in the time domain is useful, especially when short signals are analyzed.Peer ReviewedPostprint (author's final draft

Macronutrient and mineral intake effect on racing time and cardiovascular health in non-elite marathon runners.

Objective: The aim of this study was to analyze, in recreational marathon runners, the intake of specific macronutrients and minerals that could influence cardiovascular health. Methods: 37 males were grouped in two groups according to their 50% percentile race time (3.39 h), dividing into fast (G1: 3.18 ± 0.18 h) and slow runners (G2: 3.84 ± 0.42 h). Anthropometric parameters, macronutrients and mineral records were collected before the race. Minerals (Na+, K+ and Mg2+), lipid profile (triglycerides, LDL, HDL and cholesterol), muscle damage (creatine kinase), inflammation (C-reactive protein), and cardiovascular health (high-sensitive troponin-T, ST2 and N-terminal pro-B-type natriuretic peptide) were analyzed in blood 24 h before, immediately after, and 48 h post-race. Results: Weight (G1: 74.70 ± 7.76 kg, G2: 79.58 ± 6.72 kg; p < 0.05) and body mass index (G1: 23.01 ± 1.81 kg/m2, G2: 25.30 ± 2.02 kg/m2; p < 0.01) were significantly different between the groups. Moreover, G1 consumed significantly (p < 0.01) more mono- and poly-unsaturated fatty acids than G2, and presented significantly higher iron, potassium, and magnesium intake. Regarding blood lipid profile, G2 presented significantly higher triglyceride values and lower levels of high-density lipoprotein (p < 0.01). The Hs-TnT marker of cardiac myocyte stress/injury was significantly higher (p < 0.05) in G2 reaching values above 250 ng/L, and 81% of the runners (30 from 37) presented higher post-race values. Conclusions: Marathon runners consuming adequate amounts of unsaturated fat, iron, potassium and magnesium, performed better and presented better cardiovascular health.Peer ReviewedPostprint (author's final draft

Characterization and classification of patients with different levels of cardiac death risk by using Poincaré plot analysis

© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksCardiac death risk is still a big problem by an important part of the population, especially in elderly patients. In this study, we propose to characterize and analyze the cardiovascular and cardiorespiratory systems using the Poincaré plot. A total of 46 cardiomyopathy patients and 36 healthy subjets were analyzed. Left ventricular ejection fraction (LVEF) was used to stratify patients with low risk (LR: LVEF > 35%, 16 patients), and high risk (HR: LVEF = 35%, 30 patients) of heart attack. RR, SBP and T Tot time series were extracted from the ECG, blood pressure and respiratory flow signals, respectively. Parameters that describe the scatterplott of Poincaré method, related to short- and long-term variabilities, acceleration and deceleration of the dynamic system, and the complex correlation index were extracted. The linear discriminant analysis (LDA) and the support vector machines (SVM) classification methods were used to analyze the results of the extracted parameters. The results showed that cardiac parameters were the best to discriminate between HR and LR groups, especially the complex correlation index (p = 0.009). Analising the interaction, the best result was obtained with the relation between the difference of the standard deviation of the cardiac and respiratory system (p = 0.003). When comparing HR vs LR groups, the best classification was obtained applying SVM method, using an ANOVA kernel, with an accuracy of 98.12%. An accuracy of 97.01% was obtained by comparing patients versus healthy, with a SVM classifier and Laplacian kernel. The morphology of Poincaré plot introduces parameters that allow the characterization of the cardiorespiratory system dynamicsPeer ReviewedPostprint (author's final draft

Health in ultra endurance events: SUMMIT Lab® Project

High-intensity physical activity for an extended period of time could result in unhealthy disruptions to physiological systems. The main goal of the SUMMIT Lab® is to offer to ultra-endurance athletes an assessment of the impact of training with biochemical comparison of pre- and after-race measurements through biochemical (markers of muscle damage, immunity status and cardiovascular system) and physiological responses [localized muscle bioimpedance (LBIA)], cardiac function and differential gene expression. Samples were obtained from 300 participants who completed ultra-distance runs in Europe from 2012 to 2016. We found: (1) CK levels provide a gross indication of muscle-fiber damage but are not specific, they can’t identify the extent of the injury or the type of fibers affected; (2) LBIA serves to track the effects of training or a race on muscle damage, and enables longitudinal assessment of muscle injury through recovery and return to training. (3) Some individuals showed worse right ventricle adaptation during exercise independent from the training volume done or the elite profile. (4) Elite performance is mainly related with training. We have evidence that we can measure quantitatively the effect of training through a specific gene expression profile. Possible additional applications include runners, soccer, army physical condition, among others.Postprint (published version

Resonance-Based microwave technique for body implant sensing

There is an increasing need for safe and simple techniques for sensing devices and prostheses implanted inside the human body. Microwave wireless inspection may be an appropriate technique for it. The implanted device may have specific characteristics that allow to distinguish it from its environment. A new sensing technique based on the principle of differential resonance is proposed and its basic parameters are discussed. This technique allows to use the implant as a signal scattering device and to detect changes produced in the implant based on the corresponding change in its scattering signature. The technique is first tested with a canonic human phantom and then applied to a real in vivo clinical experiment to detect coronary stents implanted in swine animalsPeer ReviewedPostprint (published version

Relationship between bioimpedance vector displacement and renal function after a marathon in non-elite runners

Peer ReviewedPostprint (published version

Caracterización de pacientes isquémicos y dilatados a partir de las señales ECG y de presión sanguínea

Postprint (author's final draft