Reference Intervals and Percentile Curves of Echocardiographic Left Ventricular Mass, Relative Wall Thickness and Ejection Fraction in Healthy Children and Adolescents

Despite the clinical utility of echocardiography to measure cardiac target organ injury (TOI) there are scarcities of data about the reference intervals (RIs) and percentiles of left ventricular (LV) mass (LVM) and derived indexes (LVMI and LVMI2.7), relative wall thickness (LVRWT) and ejection fraction (LVEF) from population-based studies in children and adolescents. The aim of this study was to generate reference intervals RIs of LVM and derived indexes (LVMI and LVMI2.7), LVRWT, and LVEF obtained in healthy children, adolescents, and young adults from a South-American population. Echocardiographic studies were obtained in 1096 healthy subjects (5–24 years). Age and sex-specific RIs of LVM, LVMI, LVMI2.7, LVRWT, and LVEF were generated using parametric regression based on fractional polynomials. After covariate analysis (i.e., adjusting by age, body surface area) specific sex-specific RIs were evidenced as necessaries. Age and sex-specific 1st, 2.5th, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97.5th, and 99th percentile and curves were reported and compared with previously reported RIs. RIs showed high concordance and complementarity with what was previously reported for the population of North-American children (0–18 years old). In conclusion, in children and adolescents the interpretation of the LVM, LVMIs, LVRWT, and LVEF RIs requires sex-related RIs. This study provides the largest Argentinean database concerning RIs and percentile curves of LVM, LVMIs, LVRWT, and LVEF as markers of cardiac TOI obtained in healthy children and adolescents. These data are valuable in that they provide RIs values with which data of populations of children, adolescents can be compared.Fil: Diaz, Alberto Alejandro. Universidad Nacional del Centro de la Pcia.de Bs.as.. Escuela Superior de Ciencias de la Salud. Instituto de Investigación En Ciencias de la Salud.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Zócalo, Yanina. Universidad de la Republica. Facultad de Medicina.; UruguayFil: Bia, Daniel. Universidad de la Republica. Facultad de Medicina.; Urugua

Stroke volume and cardiac output non-invasive monitoring based on brachial oscillometry-derived pulse contour analysis: Explanatory variables and reference intervals throughout life (3–88 years)

Background: Non-invasive assessment of stroke volume (SV), cardiac output (CO) and cardiac index (CI) has shown to be useful for the evaluation, diagnosis and/or management of different clinical conditions. Through pulse contour analysis (PCA) cuff-based oscillometric devices would enable obtaining ambulatory operator-independent non-invasive hemodynamic monitoring. There are no reference intervals (RIs), when considered as a continuum in childhood, adolescence and adult life, for PCA-derived SV [SV(PCA)], CO [CO(PCA)] and CI [CI(PCA)]. The aim of the study were to analyze the associations of SV(PCA), CO(PCA) and CI(PCA) with demographic, anthropometric, cardiovascular risk factors (CVRFs) and hemodynamic parameters, and to define RIs and percentile curves for SV(PCA), CO(PCA) and CI(PCA), considering the variables that should be considered when expressing them. Methods: In 1449 healthy subjects (3–88 years) SV(PCA), CO(PCA) and CI(PCA) were non-invasively obtained (Mobil-O-Graph; Germany). Analysis: associations between subject characteristics and SV(PCA), CO(PCA) and CI(PCA) levels (correlations; regression models); RIs and percentiles for SV(PCA), CO(PCA) and CI(PCA) (parametric methods; fractional polynomials). Results: Sex, age, and heart rate would be explanatory variables for SV, CO, and CI levels. SV levels were also examined by body height, while body surface area (BSA) contributing to evaluation of CO and CI. CVRFs exposure did not contribute to independently explain the values of the dependent variables. SV, CO and CI levels were partially explained by the oscillometric-derived signal quality. RIs and percentiles were defined. Conclusions: Reference intervals and percentile for SV(PCA), CO(PCA) and CI(PCA), were defined for subjects from 3–88 years of age, results are expressed according to sex, age, heart rate, body height and/or BSA.Fil: Zócalo, Yanina. Universidad de la República. Facultad de Medicina; UruguayFil: García-Espinosa, Victoria. Universidad de la Republica. Facultad de Medicina; UruguayFil: Castro, Juan M.. Universidad de la Republica. Facultad de Medicina; UruguayFil: Zinoveev, Agustina. Universidad de la Republica. Facultad de Medicina; UruguayFil: Marin, Mariana. Universidad de la Republica. Facultad de Medicina; UruguayFil: Chiesa, Pedro. Universidad de la Republica Facultad de Medicina; UruguayFil: Diaz, Alberto Alejandro. Universidad Nacional del Centro de la Provincia de Buenos Aires. Escuela Superior de Ciencias de la Salud. Instituto de Investigación en Ciencias de la Salud; Argentina. Provincia de Buenos Aires. Municipalidad de Tandil. Hospital Municipal Ramón Santamarina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; ArgentinaFil: Bia, Daniel. Universidad de la República. Facultad de Medicina; Urugua

Pulse Wave Velocity as Marker of Preclinical Arterial Disease: Reference Levels in a Uruguayan Population Considering Wave Detection Algorithms, Path Lengths, Aging, and Blood Pressure

Carotid-femoral pulse wave velocity (PWV) has emerged as the gold standard for non-invasive evaluation of aortic stiffness; absence of standardized methodologies of study and lack of normal and reference values have limited a wider clinical implementation. This work was carried out in a Uruguayan (South American) population in order to characterize normal, reference, and threshold levels of PWV considering normal age-related changes in PWV and the prevailing blood pressure level during the study. A conservative approach was used, and we excluded symptomatic subjects; subjects with history of cardiovascular (CV) disease, diabetes mellitus or renal failure; subjects with traditional CV risk factors (other than age and gender); asymptomatic subjects with atherosclerotic plaques in carotid arteries; patients taking anti-hypertensives or lipid-lowering medications. The included subjects (n = 429) were categorized according to the age decade and the blood pressure levels (at study time). All subjects represented the “reference population”; the group of subjects with optimal/normal blood pressures levels at study time represented the “normal population.” Results. Normal and reference PWV levels were obtained. Differences in PWV levels and aging-associated changes were obtained. The obtained data could be used to define vascular aging and abnormal or disease-related arterial changes

Carotid Intima Media Thickness Reference Intervals for a Healthy Argentinean Population Aged 11-81 Years

Reference intervals (RIs) of carotid intima media thickness (CIMT) from large healthy population are still lacking in Latin America. The aim of this study was to determine CIMT RIs in a cohort of 1012 healthy subjects from Argentina. We evaluated if RIs for males and females and for left and right carotids were necessary. Second, mean and standard deviation (SD) age-related equations were obtained for left, right, and average (left + right)/2) CIMT using parametric regression methods based on fractional polynomials, in order to obtain age-specific percentiles curves. Age-specific percentile curves were obtained. Males showed higher A-CIMT ( mm versus  mm, ) in comparison with females. For males, the equations were as follows: A-CIMT mean = 0.42 + ; A-CIMT SD = 5.9 × 10−2 + . For females, they were as follows: A-CIMT mean = 0.40 + ; A-CIMT SD = 4.67 × 10−2 + . Our study provides the largest database concerning RIs of CIMT in healthy people in Argentina. Specific RIs and percentiles of CIMT for children, adolescents, and adults are now available according to age and gender, for right and left common carotid arteries.Fil: Diaz, Alberto Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Bia, Daniel. Universidad de la República; UruguayFil: Zócalo, Yanina. Universidad de la República; UruguayFil: Manterola, Hugo Luis. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Larrabide, Ignacio. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lo Vercio, Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas; ArgentinaFil: del Fresno, Mirta Mariana. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cabrera Fischer, Edmundo Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; Argentin

Vascular Accesses for Haemodialysis in the Upper Arm Cause Greater Reduction in the Carotid-Brachial Stiffness than Those in the Forearm: Study of Gender Differences

Purpose. To evaluate in chronically haemodialysed patients (CHPs), if: (1) the vascular access (VA) position (upper arm or forearm) is associated with differential changes in upper limb arterial stiffness; (2) differences in arterial stiffness exist between genders associated with the VA; (3) the vascular substitute (VS) of choice, in biomechanical terms, depends on the previous VA location and CHP gender. Methods. 38 CHPs (18 males; VA in upper arm: 18) were studied. Left and right carotid-brachial pulse wave velocity (PWVc-b) was measured. In in vitro studies, PWV was obtained in ePTFE prostheses and in several arterial and venous homografts obtained from donors. The biomechanical mismatch (BM) between CHP native vessel (NV) and VS was calculated. Results/Conclusions. PWVc-b in upper limbs with VA was lower than in the intact contralateral limbs (P < 0.05), and differences were higher (P < 0.05) when the VA was performed in the upper arm. Differences between PWVc-b in upper limbs with VA (in the upper arm) with respect to intact upper limbs were higher (P < 0.05) in males. Independently of the region in which the VA was performed, the homograft that ensured the minimal BM was the brachial artery. The BM was highly dependent on gender and the location in the upper limb in which the VA was performed

Integrated Evaluation of Age-Related Changes in Structural and Functional Vascular Parameters Used to Assess Arterial Aging, Subclinical Atherosclerosis, and Cardiovascular Risk in Uruguayan Adults: CUiiDARTE Project

This work was carried out in a Uruguayan (South American) population to characterize aging-associated physiological arterial changes. Parameters markers of subclinical atherosclerosis and that associate age-related changes were evaluated in healthy people. A conservative approach was used and people with nonphysiological and pathological conditions were excluded. Then, we excluded subjects with (a) cardiovascular (CV) symptoms, (b) CV disease, (c) diabetes mellitus or renal failure, and (d) traditional CV risk factors (other than age and gender). Subjects (n = 388) were submitted to non-invasive vascular studies (gold-standard techniques), to evaluate (1) common (CCA), internal, and external carotid plaque prevalence, (2) CCA intima-media thickness and diameter, (3) CCA stiffness (percentual pulsatility, compliance, distensibility, and stiffness index), (4) aortic stiffness (carotid-femoral pulse wave velocity), and (5) peripheral and central pressure wave-derived parameters. Age groups: ≤20, 21–30, 31–40, 41–50, 51–60, 61–70, and 71–80 years old. Age-related structural and functional vascular parameters profiles were obtained and analyzed considering data from other populations. The work has the strength of being the first, in Latin America, that uses an integrative approach to characterize vascular aging-related changes. Data could be used to define vascular aging and abnormal or disease-related changes

Central-to-peripheral blood pressure amplification: role of the recording site, technology, analysis approach, and calibration scheme in invasive and non-invasive data agreement

BackgroundSystolic blood pressure amplification (SBPA) and pulse pressure amplification (PPA) can independently predict cardiovascular damage and mortality. A wide range of methods are used for the non-invasive estimation of SBPA and PPA. The most accurate non-invasive method for obtaining SBPA and/or PPA remains unknown.AimThis study aims to evaluate the agreement between the SBPA and PPA values that are invasively and non-invasively obtained using different (1) measurement sites (radial, brachial, carotid), (2) measuring techniques (tonometry, oscillometry/plethysmography, ultrasound), (3) pulse waveform analysis approaches, and (4) calibration methods [systo-diastolic vs. approaches using brachial diastolic and mean blood pressure (BP)], with the latter calculated using different equations or measured by oscillometry.MethodsInvasive aortic and brachial pressure (catheterism) and non-invasive aortic and peripheral (brachial, radial) BP were simultaneously obtained from 34 subjects using different methodologies, analysis methods, measuring sites, and calibration methods. SBPA and PPA were quantified. Concordance correlation and the Bland–Altman analysis were performed.Results(1) In general, SBPA and PPA levels obtained with non-invasive approaches were not associated with those recorded invasively. (2) The different non-invasive approaches led to (extremely) dissimilar results. In general, non-invasive measurements underestimated SBPA and PPA; the higher the invasive SBPA (or PPA), the greater the underestimation. (3) None of the calibration schemes, which considered non-invasive brachial BP to estimate SBPA or PPA, were better than the others. (4) SBPA and PPA levels obtained from radial artery waveform analysis (tonometry) (5) and common carotid artery ultrasound recordings and brachial artery waveform analysis, respectively, minimized the mean errors.ConclusionsOverall, the findings showed that (i) SBPA and PPA indices are not “synonymous” and (ii) non-invasive approaches would fail to accurately determine invasive SBPA or PPA levels, regardless of the recording site, analysis, and calibration methods. Non-invasive measurements generally underestimated SBPA and PPA, and the higher the invasive SBPA or PPA, the higher the underestimation. There was not a calibration scheme better than the others. Consequently, our study emphasizes the strong need to be critical of measurement techniques, to have methodological transparency, and to have expert consensus for non-invasive assessment of SBPA and PPA

Aortic systolic and pulse pressure invasively and non-invasively obtained: Comparative analysis of recording techniques, arterial sites of measurement, waveform analysis algorithms and calibration methods

Background: The non-invasive estimation of aortic systolic (aoSBP) and pulse pressure (aoPP) is achieved by a great variety of devices, which differ markedly in the: 1) principles of recording (applied technology), 2) arterial recording site, 3) model and mathematical analysis applied to signals, and/or 4) calibration scheme. The most reliable non-invasive procedure to obtain aoSBP and aoPP is not well established.Aim: To evaluate the agreement between aoSBP and aoPP values invasively and non-invasively obtained using different: 1) recording techniques (tonometry, oscilometry/plethysmography, ultrasound), 2) recording sites [radial, brachial (BA) and carotid artery (CCA)], 3) waveform analysis algorithms (e.g., direct analysis of the CCA pulse waveform vs. peripheral waveform analysis using general transfer functions, N-point moving average filters, etc.), 4) calibration schemes (systolic-diastolic calibration vs. methods using BA diastolic and mean blood pressure (bMBP); the latter calculated using different equations vs. measured directly by oscillometry, and 5) different equations to estimate bMBP (i.e., using a form factor of 33% (“033”), 41.2% (“0412”) or 33% corrected for heart rate (“033HR”).Methods: The invasive aortic (aoBP) and brachial pressure (bBP) (catheterization), and the non-invasive aoBP and bBP were simultaneously obtained in 34 subjects. Non-invasive aoBP levels were obtained using different techniques, analysis methods, recording sites, and calibration schemes.Results: 1) Overall, non-invasive approaches yielded lower aoSBP and aoPP levels than those recorded invasively. 2) aoSBP and aoPP determinations based on CCA recordings, followed by BA recordings, were those that yielded values closest to those recorded invasively. 3) The “033HR” and “0412” calibration schemes ensured the lowest mean error, and the “033” method determined aoBP levels furthest from those recorded invasively. 4) Most of the non-invasive approaches considered overestimated and underestimated aoSBP at low (i.e., 80 mmHg) and high (i.e., 180 mmHg) invasive aoSBP values, respectively. 5) The higher the invasively measured aoPP, the higher the level of underestimation provided by the non-invasive methods.Conclusion: The recording method and site, the mathematical method/model used to quantify aoSBP and aoPP, and to calibrate waveforms, are essential when estimating aoBP. Our study strongly emphasizes the need for methodological transparency and consensus for the non-invasive aoBP assessment

Comparative analysis of arterial stiffness non invasively evaluated in hemodialyzed patients

pacientes hemodializados se producen en vasos elásticos y musculares pero sólo la Velocidad de la Onda del Pulso (VOP) aórtica ha demostrado ser un índice de alto valor pronóstico. Lo cual deja de lado a las arterias musculares. Los objetivos del estudio fueron: a) medir la VOP aórtica y la carotido-radial de pacientes hemodializados, y b) repetir el análisis anterior en la misma cohorte 5 años después, comparando cuatro índices diferentes de rigidez arterial. Material y métodos: a 23 pacientes hemodializados se les evaluó la VOP aórtica (VOPcf), la carotido-radial (VOPcr) y se calculó: la VOP centro-periférica (VOPcp), la diferencia (ΔVOP), el desacople de VOP y su cambio porcentual (%VOP). Las evaluaciones se hicieron en 2007 (Tiempo 1) y en 2012 (Tiempo 2). Resultados: La VOPcp mostró un aumento significativo entre la evaluación realizada entre el Tiempo 1 y el 2 (de 1.1±0.3 a 1.4±0.4; p<0.01). En los mismos tiempos ΔVOP mostró que los valores se incrementaban en términos negativos (de -0.9±3.0 a -2.7±2.9; p<0.05). El desacople de la rigidez centro-periférica mostró un significativo aumento (valores negativos) entre el Tiempo 1 y 2 (de 0.0±0.1 a -0.1±0.1; p<0.02). El %VOP ANÁLISIS COMPARATIVO DE LA RIGIDEZ ARTERIAL EVALUADA EN FORMA NO INVASIVA EN PACIENTES HEMODIALIZADOS COMPARATIVE ANALYSIS OF ARTERIAL STIFFNESS NON INVASIVELY EVALUATED IN HEMODIALYZED PATIENTS Cinthia Galli (1,2), Rodolfo Valtuille (3), Maia Daniela Percunte (2), Nahuel Hernán Carrizo (2), Daniel Bia (4), Ricardo Armentano (1,2), Edmundo Cabrera Fischer (1,2) 1) Área de Investigación y Desarrollo Universidad de Favaloro (AIDUF), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 2) Facultad Regional Buenos Aires, Universidad Tecnológica Nacional, Buenos Aires 3) Fresenius FME Burzaco, Buenos Aires 4) Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay Nefrología, Diálisis y Trasplante 2016; 36 (1) Pág. 26-33 entre ambas mediciones (valores negativos) mostró un significativo aumento (de -4.8±22.0 a -21.5±24.2; p<0.05). Conclusiones: en la presente investigación los índices de rigidez obtenidos en pacientes hemodializados, incluyendo arterias tanto elásticas y musculares, mostraron diferencias estadísticamente significativas cuando se compararon dos mediciones separadas por cinco años. Sin embargo los niveles de significación no fueron similares.Objectives: Changes in arterial stiffness in hemodialysis patients occur both, in elastic and muscular vessels but only the aortic Pulse Wave Velocity (PWV) has demonstrated to be a high prognostic value index, however, muscular arteries are not involved in the aortic PWV measurement. The purpose of this research was: a) to evaluate the aortic and carotid-radial PWV of hemodialysis patients, b) to repeat these measurements in the same cohort after 5 years comparing four different arterial stiffness indexes. Methods: 23 hemodialyzed patients carotid-femoral PWV (PWVcf) and carotidradial (PWVcr) were evaluated and calculations were as follows: PWV ratio, PWV difference (/ PWV), PWV mismatch and PWV percentage change (%PWV). These evaluations were performed using data obtained in 2007 (Time 1) and 2012 (Time 2). Results: PWV ratio showed a significant increase between measurements performed in Time 1 and 2 (from 1.1±0.3 to 1.4±0.4; p≤0.01). Similar increases in negative terms were found when /PWV was calculated from -0.9±3.0 to -2.7±2.9; p≤0.05) Calculated values of PWV mismatch increased significantly (negative values) between Time 1 and 2 (from 0.0±0.1 to -0.1±0.1; p≤0.02) Percent changes of PWV between Time 1 and 2 (negative values) showed a significant increase (from -4.8±22.0 to -21.5±24.2; p≤0.05). Conclusions: Stiffness indexes, obtained in hemodialyzed patients including both elastic and muscular arteries used in this research showed statistically significant differences when two measures with 5 years interval were compared. However significance levels were not similar.Fil: Galli, Cintia Nora. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Universidad Favaloro. Área de Investigación y Desarrollo; ArgentinaFil: Valtuille, Rodolfo. Fresenius Medical Care Burzaco; ArgentinaFil: Percunte, Maia Daniela. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Carrizo, Nahuel Hernán. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Bia, Daniel. Universidad de la República; UruguayFil: Armentano, Ricardo Luis. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Universidad Favaloro. Área de Investigación y Desarrollo; ArgentinaFil: Cabrera Fischer, Edmundo Ignacio. Universidad Favaloro. Área de Investigación y Desarrollo; Argentina. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Pulse wave velocity as marker of preclinical arterial disease: reference levels in a uruguayan population considering wave detection algorithms, path lengths, aging, and blood pressure

Carotid-femoral pulse wave velocity (PWV) has emerged as the gold standard for non-invasive evaluation of aortic stiffness; absence of standardized methodologies of study and lack of normal and reference values have limited a wider clinical implementation. This work was carried out in a Uruguayan (South American) population in order to characterize normal, reference, and threshold levels of PWV considering normal age-related changes in PWV and the prevailing blood pressure level during the study. A conservative approach was used, and we excluded symptomatic subjects; subjects with history of cardiovascular (CV) disease, diabetes mellitus or renal failure; subjects with traditional CV risk factors (other than age and gender); asymptomatic subjects with atherosclerotic plaques in carotid arteries; patients taking anti-hypertensives or lipid-lowering medications. The included subjects (n = 429) were categorized according to the age decade and the blood pressure levels (at study time). All subjects represented the &quot;reference population&quot;; the group of subjects with optimal/normal blood pressures levels at study time represented the &quot;normal population.&quot; Results. Normal and reference PWV levels were obtained. Differences in PWV levels and aging-associated changes were obtained. The obtained data could be used to define vascular aging and abnormal or disease-related arterial changes