Pre-ejection Period Research Articles

Internalizing Problems and Attentional Control

Abstract. Individuals with internalizing problems differ in levels of attentional control (AC), and this heterogeneity could be associated with differences in autonomic arousal. The present study investigated whether AC moderated the effect of internalizing problems on self-reported experience and autonomic nervous system (ANS) responses after the induction of negative affect. Children aged 9–13 years were recruited into a patient group (29) and a healthy control group (25). AC was measured by the Early Adolescent Temperament Questionnaire. Heart rate, heart rate variability (HRV) and pre-ejection period (PEP) were recorded during baseline, a sad film clip and recovery, and analyzed using a marginal linear model. Children reported their experienced emotion, valence, and arousal in response to the film. A significant interaction effect showed increased HRV and longer PEP from baseline to recovery for patients with higher AC. Patients with lower AC showed increased HRV followed by a return to baseline values after the film clip and no significant changes in PEP. Healthy controls showed no significant changes in HRV or PEP independent of level of AC. There were no differences between groups in self-reported experience. The results indicate that AC moderated the effect of internalizing problems on ANS regulation. Increased HRV and longer PEP from baseline to recovery were uniquely associated with higher AC and internalizing problems. This physiological response might indicate a cognitive avoidance strategy. AC could be an important factor explaining heterogeneity in ANS activity among individuals with internalizing problems. Clinical implications of the present findings are discussed.

Investigating Flow State and Cardiac Pre-ejection Period During Electronic Gaming Machine Use.

Flow activities (e.g. sports and gaming) have been associated with positive affect and prolonged engagement. In the gambling field, modern electronic gaming machines (EGMs, including modern slot machines) have drawn concern as a potentially flow-inducing activity that may be associated with gambling-related harms. Current research has heavily relied on self-reported flow, and further insights may be afforded by physiological methods. We present data from three separate experiments in which self-reported gambling flow and cardiac pre-ejection period (PEP; a measure of sympathetic nervous system arousal) were examined. Male undergraduate participants gambled on a genuine EGM in a laboratory setting for a period of at least 15 min, and completed the Flow subscale of the game experience questionnaire (GEQ). Aggregated data were analyzed using multilevel regression. Although EGM gambling was not associated with significant changes in PEP across participants, we found that self-reported flow states were associated with significant decreases in PEP during the first five minutes of EGM use. Thus, participants who experienced flow showed a greater sympathetic nervous system response to the onset of gambling. Though these effects were consistent in experiments 1 and 2, in experiment 3 the effect was inverted during the same time window. We conclude that flow during EGM gambling appears to be associated with early changes in sympathetic nervous system activity, but stress that more research is needed to characterize boundary conditions and moderating factors.

Differences in pulse rate variability with measurement site

BackgroundRecently, attempts have been made to use the pulse rate variability (PRV) as a surrogate for heart rate variability (HRV). PRV, however, may be caused by the fluctuations of left ventricular pre-ejection period and pulse transit time besides HRV. We examined whether PRV differs not only from HRV but also depending on the measurement site.ResultsIn five healthy subjects, pulse waves were measured simultaneously on both wrists and both forearms together with single-lead electrocardiogram (ECG) in the supine and sitting positions. Although average pulse interval showed no significant difference from average R-R interval in either positions, PRV showed greater power for the low-frequency (LF) and high-frequency (HF) components and lower LF/HF than HRV. The deviations of PRV from HRV in the supine and sitting positions were 13.2% and 7.9% for LF power, 24.5% and 18.3% for HF power, and − 15.0% and − 30.2% for LF/HF, respectively. While the average pulse interval showed 0.8% and 0.5% inter-site variations among the four sites in the supine and sitting positions, respectively, the inter-site variations in PRV were 4.0% and 3.6% for LF power, 3.8% and 4.7% for HF power, and 18.0% and 17.5% for LF/HF, respectively.ConclusionsThese suggest that PRV shows not only systemic differences from HRV but also considerable inter-site variations.

Cortical and affective regulation of autonomic coordination.

Although anatomical research clearly demonstrates the ability of the sympathetic and parasympathetic branches of the autonomic nervous system to independently influence cardiac function, little research has examined whether coordinated activation is typical or whether the extent of autonomic coordination is situationally dependent. This study examines the extent of coordination between sympathetic (cardiac pre-ejection period: PEP) and parasympathetic (respiratory sinus arrhythmia: RSA) influences on the cardiac function to determine whether coordination is a trait-like between-person characteristic or a state-varying within-person phenomenon, and if so, whether variability in autonomic coordination is modulated by cognitive (P3b amplitude) or affective state. Kindergarten-aged children (n=257) completed a go/no-go task administered in blocks designed to induce affective states through the delivery of reward (Blocks 1 and 3) and frustration (Block 2). Results from multilevel models that allowed for the simultaneous examination of between-person and within-person associations in the repeated measures data suggested that (a) children with higher overall RSA also tended to have higher overall PEP; (b) at within-person level, RSA and PEP tended to be reciprocally coordinated; but that (c) when frustration invokes cognitive disengagement, coordination between parasympathetic and sympathetic systems demonstrate compensatory coordination. These findings highlight the extent to which the coordination of autonomic systems is a dynamic state-like phenomenon rather than a trait-like individual differences characteristic.

The repeatability of estimated systolic time intervals in healthy subjects using seismocardiogram and electrocardiogram

Objective: We investigated the repeatability of systolic time intervals (STIs) in healthy subjects using a combination of seismocardiogram (SCG) and electrocardiogram (ECG). STIs have been extensively used in the past to quantify heart performance, particularly the left ventricle. In this study, STIs included pre-ejection period (PEP), left ventricular ejection time (LVET), and their ratio. Approach: We conducted the repeatability test of STI estimation through two experiments. The first involved three consecutive one-minute recordings separated by one-minute intervals, and the second involved two one-minute recordings separated by 24 h. Twenty healthy subjects participated in our study. We considered the coefficient of variation (CV) to quantify the repeatability. As there was no agreed upon values for optimal CV values, we compared our results with an alternative method using a combination of impedance cardiography (ICG) and ECG. Similar to our method, the alternative method was noninvasive and could be employed for personal heart monitoring. We also studied the repeatability after STIs were corrected for heart rate using two approaches. The first approach used a multiplicative factor per subject based on the heart rates in each recordings of that subject. The second approach employed sex-specific regression models for all subjects (Weissler’s equations). Main results: We found that the repeatability of our method (SCG and ECG) was in agreement with the alternative method (ICG and ECG) in both experiments. Moreover, the Weissler’s equations approach for heart rate increased the repeatability. Significance: It can be concluded that estimation of PEP, LVET and their ratio through SCG and ECG signals was repeatable in healthy subjects.

Associations Between Colonic Motor Patterns and Autonomic Nervous System Activity Assessed by High-Resolution Manometry and Concurrent Heart Rate Variability.

Abnormal colonic motility may be associated with dysfunction of the autonomic nervous system (ANS). Our aim was to evaluate if associations between colonic motor patterns and autonomic neural activity could be demonstrated by assessing changes in heart rate variability (HRV) in healthy volunteers. A total of 145 colonic motor patterns were assessed in 11 healthy volunteers by High-Resolution Colonic Manometry (HRCM) using an 84-channel water-perfused catheter. Motor patterns were evoked by balloon distention, a meal and luminal bisacodyl. The electrocardiogram (ECG) and cardiac impedance were assessed during colonic manometry. Respiratory sinus arrhythmia (RSA) and root mean square of successive differences of beat-to-beat intervals (RMSSD) served as measures of parasympathetic reactivity while the Baevsky’s Stress Index (SI) and the pre-ejection period (PEP) were used as measures of sympathetic reactivity. Taking all motor patterns into account, our data show that colonic motor patterns are accompanied by increased parasympathetic activity and decreased sympathetic activity that may occur without eliciting a significant change in heart rate. Motor Complexes (more than one motor pattern occurring in close proximity), High-Amplitude Propagating Pressure Waves followed by Simultaneous Pressure Waves (HAPW-SPWs) and HAPWs without SPWs are all associated with an increase in RSA and a decrease in SI. Hence RSA and SI may best reflect autonomic activity in the colon during these motor patterns as compared to RMSSD and PEP. SI and PEP do not measure identical sympathetic reactivity. The SPW, which is a very low amplitude pressure wave, did not significantly change the autonomic measures employed here. In conclusion, colonic motor patterns are associated with activity in the ANS which is reflected in autonomic measures of heart rate variability. These autonomic measures may serve as proxies for autonomic neural dysfunction in patients with colonic dysmotility.

Autonomic influences on heart rate during marital conflict: Associations with high frequency heart rate variability and cardiac pre-ejection period

Psychosocial factors predict the development and course of cardiovascular disease, perhaps through sympathetic and parasympathetic mechanisms. At rest, heart rate (HR) is under parasympathetic control, often measured as high-frequency heart rate variability (HF-HRV). During stress, HR is influenced jointly by parasympathetic and sympathetic processes, the latter often quantified as pre-ejection period (PEP). In studies of cardiovascular risk factors that involve social interaction (e.g. marital conflict), HF-HRV might be altered by speech artifacts, weakening its validity as a measure of parasympathetic activity. To evaluate this possibility, we tested associations of HF-HRV and PEP with HR at rest and across periods of marital conflict interaction that varied in experimentally-manipulated degrees of speech in 104 couples. At rest, only HF-HRV was independently related to HR, for both husbands and wives. During speaking, listening, and recovery periods, husbands’ and wives’ HF-HRV and PEP change independently predicted HR change. These findings support interpretation of HF-HRV as a parasympathetic index during stressful social interactions that may confer risk for cardiovascular disease.

Sex differences in emotional concordance

Emotions involve response synchronization across experiential, physiological, and behavioral systems, referred to as concordance or coherence. Women are thought to be more emotionally aware and expressive than men and may therefore display stronger response concordance; however, research on this topic is scant. Using a random-order film-average design, we assessed concordance among experiential (arousal, valence), autonomic (electrodermal activity, heart rate, preejection period, respiratory sinus arrhythmia), respiratory (respiratory rate), and behavioral (corrugator and zygomatic electromyography) responses to 15 two-minute films varying in valence and arousal. We then calculated for each participant and pair of measures a within-subject correlation index using averages from the 15 films. Pronounced individual concordance of up to 0.9 was observed. Arousal-physiology and valence-behavior concordances were particularly pronounced. Women displayed higher concordance than men for almost all pairs of measures. Findings indicate stronger psychophysiological response coupling in women than men and provide novel insights into affective differences between the sexes.

Sympathetic contributions to habituation and recovery of the cardiac defense response

The cardiac defense response (CDR) to intense auditory stimulation is characterized by two acceleration-deceleration heart rate (HR) components. This study investigated contributions of sympathetic cardiac control to habituation and recovery of the CDR. Fifty-six healthy subjects were presented with noise stimuli eliciting the CDR. Three stimuli were presented with short and long (2.5 min and 12.5 min) inter-trial intervals (ITIs). The pre-ejection period was recorded as an index of sympathetic cardiac control, in addition to HR. Repeated stimulation at short ITI was associated with marked habituation of the HR and sympathetic responses; both responses exhibited a degree of recovery with long ITI. Regarding the time course, the first acceleration-deceleration was accompanied by a decline and subsequent increase in sympathetic cardiac control. During the second acceleration-deceleration, the parameters exhibited parallel courses. These results suggest that the sympathetic contribution to the habituation and recovery is limited to the second HR component.

Systolic Time Interval (STI) in Hypothyroid Patients Receiving High Dose L-Thyroxine

Introduction: Systolic Time Interval (STI) is a simple,noninvasive and precise technique to assess left ventricular (LV) function. It measures aortic Pre-Ejection Period (PEP) over Left Ventricular Ejection Time (LVET) from echocardiogram. Thyrotoxicosis will enhance LV function and cause reduction of STI. This study was perform to measure the changes of STI after administration of high dose L-thyroxine and to determine the correlation between high dose L-thyroxine administration and STI. Materials and Method: A Total of 22 patients were screened. Those with cardiac diseases and high Framingham risk score were excluded. Nine patients were started on high dose L-thyroxine (7x their usual dose) once a week during the month of Ramadan.Thyroid hormones ( T3,T4,TSH)Â and STI (PEP/LVET) were measured at baseline and within 24 hrs after high dose L-thyroxine ingestion. Results: All patients have normal thyroid hormones level and normal cardiac function at baseline. The median dose (mcg) of L-thyroxine was 600 (437.5,700) while the median level of fT4 (pmol/L) was 17.43(12.38,20.8). Despite the significant increment of fT4 after Lthyroxine ingestion [baseline 13.21(8.19,14.63) vs high dose 17.43(12.38,22.55) p; 0.011] there was no significant change in STI [baseline 0.3(0.2,0.4) vs high dose 0.28(0.26,0.45) p; 0.513]. There was no correlation found between the dose of Lthyroxine and STI (r=0.244 , p;0.526). Conclusion: Administration of high dose Lthyroxine did not significantly alter STI despite significant increment of fT4 level unlike the naturally occurring thyrotoxicosis.Therefore ‘exogenous’ administration of high dose L-thyroxine is cardiac safe.

The short Sing-a-Song Stress Test: A practical and valid test of autonomic responses induced by social-evaluative stress.

The Sing-a-Song Stress Test (SSST) was recently developed as an alternative to the Trier Social Stress Test (TSST) to investigate autonomic nervous system responses to social-evaluative stress. In the SSST, participants are suddenly cued to sing a song in the presence of confederates. However, the SSST is still quite long (~15min) and the requirement for confederates makes it labor-intensive. The current study tested whether a shorter (~6.5min), single-experimenter, version of the SSST can still reliably elicit subjective and physiological stress reactivity. Our sample consisted of 87 healthy young adult participants (age range: 18-35years). During the short SSST and a speeded reaction time task, in which aversive loud tones were to be avoided (TA), we measured heart period (HP), sympathetic nervous system (SNS) activity using pre-ejection-period (PEP), skin conductance level (SCL), and non-specific skin conductance responses (ns.SCR), and parasympathetic nervous system (PNS) activity using respiratory-sinus-arrhythmia (RSA) and the root-mean-square of successive differences (RMSSD). The short SSST induced significant decreases in positive affect and increases in negative affect. MANOVAs on the clusters of SNS and PNS variables showed that the short SSST elicited significant HP (-118.46ms), PEP (-7.76ms), SCL (+4.85 μS), ns.SCR (+8.42 peaks/min) and RMSSD (-14.67) reactivity. Affective, SNS, and PNS reactivity to the new SSST social-evaluative stress task were of comparable magnitude to that evoked by the TA mental stressor. We conclude that the short SSST is a valid and cost-effective task for large scaled studies to induce social-evaluative stress to a sufficient degree to evoke measurable changes in PNS and SNS activity and affective state.

New non-invasive approach to detect cardiac contractility using the first sound of phonocardiogram.

AimDuring surgery, a non‐invasive and easy‐to‐use method is required for evaluating left ventricular status. The systolic time interval, including pre‐ejection period (PEP), of left ventricle has been known to be correlated with cardiac contractility. In this study, we focused on the non‐invasive time interval from the Q wave of an electrocardiogram to the third component in the first heart sound (QS1‐3rd) and evaluated the correlation between PEP and peak differentiated left ventricular pressure (LV dp/dt).MethodsSix adult anesthetized pigs were intubated. Mechanical ventilation was started. An electrocardiogram, carotid artery blood pressure, left ventricular pressure, and phonocardiogram on the fourth left intercostal space were monitored using a polygraph system. Cardiac output was measured by the thermodilution method. Data were simultaneously measured at baseline and after the infusion of noradrenaline, nitroprusside, esmolol sulfate, and dobutamine, respectively. Data were analyzed by Spearman’s rank correlation coefficient using four‐quadrant plot analysis.ResultsA total of 270 points were simultaneously measured. The QS1‐3rd showed a significant correlation with PEP (QS1‐3rd = 7.62 + 0.92 PEP; ρ = 0.91, P < 0.0001). Concordance rate was 92% between PEP and QS1‐3rd (excluded zones were set within ± 5 ms). Both PEP and QS1‐3rd showed a good correlation with LV dp/dt (LV dp/dt = 3861.3–24.4 PEP; ρ = 0.85, P < 0.0001, LV dp/dt = 3763.6–23.5 QS1‐3rd; ρ = 0.82, P < 0.0001).ConclusionThis non‐invasive and easy‐to‐use hemodynamic parameter (QS1‐3rd) could be helpful for continuous monitoring of left cardiac contraction performance.

420 Vortex formation in the pre-ejection phase in the left ventricle

Abstract Funding Acknowledgements Central Norway Regional Health Authority Background/Introduction: Vortex formation during left ventricular filling have been described since the 1980’s. We have investigated vortices in the left ventricle (LV) in healthy adults with a new technology based on high frame rate vector flow imaging (VFI) using blood speckle tracking. Purpose In this study we investigated the intraventricular flow pattern during the pre-ejection period. Material and methods We examined 21 healthy volunteers with a GE E95 ultrasound scanner, both in ordinary clinical mode and with an experimental setup. The latter was developed to achieve high frame rates by utilizing plane waves in combination with ECG-gating over multiple (5-6) heart cycles, allowing continuous acquisition of &amp;gt; 3500 FPS. Blood speckle tracking followed by model based regularization was used to obtain vector flow velocity measurements. Results During the pre-ejection phase we observed blood flow from the apex to the basis of the LV along the septum. At the base, the flow is deflected. A basal vortex is then created just above the mitral valve, which persists into the isovolumetric contraction (IVC). The lateral part of the vortex is then seen as an apically directed flow during IVC, as shown in the illustration. The vortex is also visible in the first phase of the ejection; the part of the blood in the LV not passing through the aortic valve is deflected and continues to conserve this vortex. These findings correspond to patterns found in colour M-Mode (CMM), showing a column of blood toward the apex in the IVC/early ejection phase. Time from peak R to the first sighting of this IVC vortex, and to the pre-ejection spike in tissue Doppler imaging (TDI), are similar, as reported in table 1. Conclusion(s): Our imaging setup allows for a very high temporal resolution (&amp;gt;3500 FPS), and enables VFI using blood speckle tracking, without using a contrast agent. We observed an intraventricular vortex during pre-ejection and into early ejection, with the same direction as the later vortices seen in filling. Initiation of this vortex may be conserved energy from late filling. This vortex is simultaneous with the pre-ejection spike in TDI. We postulate that this IVC vortex contributes to the closing of the anterior mitral leaflet in the IVC. As we also observe this vortex during the early ejection phase, we believe it may conserve rotational energy into early filling. Table 1 Timing of the IVC vortex and the pre-ejection spike in TDI Mean Median SD Min Max Time between R and the basal vortex during IVS (ms) 16,7 16 15,1 -13 47 Time between R and the pre-ejection spike TDI (ms) 16,3 21 14,4 -10 36 Abstract 420 Figure.

Association between systolic ejection time and outcomes in heart failure by ejection fraction.

Worsening heart failure (HF) is associated with shorter left ventricular systolic ejection time (SET), but there are limited data describing the relationship between SET and clinical outcomes. Thus, the objective was to describe the association between SET and clinical outcomes in an ambulatory HF population irrespective of ejection fraction (EF). We identified ambulatory patients with HF with reduced EF (HFrEF) and HF with preserved EF (HFpEF) who had an outpatient transthoracic echocardiogram performed between August 2008 and July 2010 at a tertiary referral centre. Multivariable logistic regression was used to evaluate the association between SET and 1-year outcomes. A total of 545 HF patients (171 HFrEF, 374 HFpEF) met eligibility criteria. Compared with HFpEF, HFrEF patients were younger [median age 60 years (25th-75th percentiles 50-69) vs. 64 years (25th-75th percentiles 53-74], with fewer females (30% vs. 56%) and a similar percentage of African Americans (36% vs. 35%). Median (25th-75th percentiles) EF with HFrEF was 30% (25-35%) and with HFpEF was 54% (48-58%). Median SET was shorter (280ms vs. 315 ms, P < 0.001), median pre-ejection period was longer (114ms vs. 89 ms, P < 0.001), and median relaxation time was shorter (78.7ms vs. 93.3 ms, P < 0.001) among patients with HFrEF vs. HFpEF. Death or HF hospitalization occurred in 26.9% (n=46) HFrEF and 11.8% (n=44) HFpEF patients. After adjustment, longer SET was associated with lower odds of the composite of death or HF hospitalization at 1year among HFrEF but not HFpEF patients. Longer SET is independently associated with improved outcomes among HFrEF patients but not HFpEF patients, supporting a potential role for normalizing SET as a therapeutic strategy with systolic dysfunction.

Effect of hemodialysis on impedance cardiography (electrical velocimetry) parameters in children.

Pediatric hemodialysis (HD) patients have a high incidence of cardiovascular morbidity and mortality. The study aim was to investigate whether impedance cardiography (electrical velocimetry, EV) is suitable as a hemodynamic trend monitoring tool in pediatric patients during HD. Measurements by EV were obtained before, during, and after HD in a prospective single-center pediatric observational study. In total, 54 dialysis cycles in four different pediatric patients with end-stage kidney disease on chronic HD were included. EV parameters analyzed were heart rate (HR), stroke volume (SV), stroke volume index (SI), cardiac output (CO), cardiac index (CI), thoracic fluid content (TFC), index of contractility (ICON), stroke volume variation (SVV), variation of ICON (VIC), R-R interval (TRR), pre-ejection period (PEP), left ventricular ejection time (LVET), and systolic time ration (STR). Systemic vascular resistance index (SVRI) was calculated. EV did measure significant changes in cardiovascular parameters associated with HD. The following parameters increased after HD: HR (9%), SVV (19%), VIC (33%), PEP (8%), and STR (18%). A decrease after HD was measured in SV (18%), SI (18%), CO (10%), CI (10%), TFC (10%), ICON (7%), TRR (7%), LVET (8%), and LVET (8%). SVRI was not affected by HD. The changes were correlated to ultrafiltration. HD cycles without fluid withdrawal also altered cardiovascular parameters. Pediatric HD with and without fluid withdrawal changes hemodynamic EV monitoring parameters. Possibly EV may be useful to optimize HD management in pediatric patients.

Emotion Regulation via the Autonomic Nervous System in Children with Attention-Deficit/Hyperactivity Disorder (ADHD): Replication and Extension.

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent disorder characterized by symptoms of inattention, hyperactivity, and/or impulsivity, as well as executive dysfunction. Recent work underlines the importance in understanding the role of emotion reactivity and regulatory deficits in the context of the disorder. One study (i.e., Musser et al. 2011) utilized a positive and negative emotion induction and suppression task, as well as indexes of autonomic nervous system reactivity, to examine emotional functioning in youth with ADHD. This study revealed inflexible parasympathetic-based regulation across emotion conditions among youth with ADHD compared to typically developing youth. The present study sought to replicate and extend these findings to a clinically recruited, diverse sample, while also examining sympathetic functioning. Two hundred fifty-nine participants (160 youth with ADHD), aged 5 to 13, completed the task utilized in Musser et al. 2011, while indexes of parasympathetic (i.e., respiratory sinus arrhythmia [RSA]) and sympathetic (i.e., pre-ejection period [PEP] and electrodermal activity [EDA]) reactivity were obtained. ADHD was associated with significantly elevated parasympathetic (i.e., augmented RSA) and sympathetic (as indexed by EDA) reactivity. Overall, results replicate and extend Musser et al. 2011, revealing sympathetic-linked disruptions in emotion reactivity and parasympathetic-linked disruptions in emotion regulation among youth with ADHD. Future studies of behavioral therapies for ADHD should consider the efficacy of adding an emotion regulation skills training component.

Long-term Non-invasive Hemodynamic Evaluation of Left Endocardial Cardiac Resynchronization Therapy

Introduccion: La VAB es una cardiopatia congenita que puede asociarse a complicaciones aorticas y/o valvulares. Resulta importante identificar grupos de riesgo, para realizar un seguimiento mas estrecho e indicar la intervencion a tiempo. El siguiente trabajo busca analizar el impacto que tienen las caracteristicas clinicas y morfologicas valvulares en el desarrollo de disfuncion valvular aortica moderada/severa (significativa) y en la incidencia de eventos cardiovasculares mayores en adultos con VAB. Materiales y metodos: Se incluyeron pacientes consecutivos con diagnostico de VAB no sindromatica (2010-2019) en seguimiento en nuestra institucion. Se recabo informacion clinica y ecocardiografica de manera prospectiva. Se realizo analisis uni y multivariado para identificar caracteristicas clinicas y morfologicas predictoras de disfuncion valvular significativa y de eventos cardiovasculares mayores (muerte/cirugia/sindrome aortico). Una p menor 0,05 fue considerada significativa. Resultados: Se incluyeron 300 pacientes (44.3±15.3 anos, 71% hombres). La mayoria con VAB tipo I y presencia de rafe (79.6% y 77%, respectivamente). La edad media de diagnostico fue de 36.3 ±16.2 anos. Hubo 84 pacientes (31.2%) que presentaban disfuncion valvular aortica significativa al momento del inicio del estudio. Con un seguimiento a 4.9 ± 1.7 anos, 23 pacientes requirieron cirugia cardiaca (7.7%) y 3 fallecieron (1%). Al final del seguimiento 101 (33.6%) pacientes presentaban disfuncion valvular aortica significativa. La presencia de al menos 1 de los siguientes factores: prolapso valvular, calcificacion valvular aortica basal >1 y una edad > 50 anos se asocio a menor sobrevida libre de disfuncion valvular aortica significativa y de eventos mayores. Conclusiones: En nuestra cohorte, observamos una alta incidencia de eventos asociados a VAB. Dentro de las variables analizadas, la presencia de al menos 1 factor de riesgo se asocio a menor sobrevida libre de eventos mayores y disfuncion significativa a 4,9 anos.

Blood Pressure Estimation Using On-body Continuous Wave Radar and Photoplethysmogram in Various Posture and Exercise Conditions

The pulse arrival time (PAT), pre-ejection period (PEP) and pulse transit time (PTT) are calculated using on-body continuous wave radar (CWR), Photoplethysmogram (PPG) and Electrocardiogram (ECG) sensors for wearable continuous systolic blood pressure (SBP) measurements. The CWR and PPG sensors are placed on the sternum and left earlobe respectively. This paper presents a signal processing method based on wavelet transform and adaptive filtering to remove noise from CWR signals. Experimental data are collected from 43 subjects in various static postures and 26 subjects doing 6 different exercise tasks. Two mathematical models are used to calculate SBPs from PTTs/PATs. For 38 subjects participating in posture tasks, the best cumulative error percentage (CEP) is 92.28% and for 21 subjects participating in exercise tasks, the best CEP is 82.61%. The results show the proposed method is promising in estimating SBP using PTT. Additionally, removing PEP from PAT leads to improving results by around 9%. The CWR sensors present a low-power, continuous and potentially wearable system with minimal body contact to monitor aortic valve mechanical activities directly. Results of this study, of wearable radar sensors, demonstrate the potential superiority of CWR-based PEP extraction for various medical monitoring applications, including BP measurement.

Cardiac autonomic functioning and post-traumatic stress: A preliminary study in youth at-risk for PTSD

The identification of robust, psychophysiological markers of trauma-related distress is critical for developing comprehensive, trauma-informed, mental health assessments for youth. Thus, the present study examined the clinical utility of cardiac autonomic balance (CAB) and cardiac autonomic regulation (CAR), two composite indices of the sympathetic and parasympathetic nervous system. We hypothesized that CAB/CAR would more reliably index post-traumatic stress (PTS) responses compared to measuring the parasympathetic (i.e., respiratory sinus arrhythmia; RSA) and sympathetic (i.e., pre-ejection period; PEP) nervous systems in isolation. Our sample was comprised of 88 diverse, low-income youth (40.9% African-American and 36.4% White; 60.5% girls; Mage = 12.05 years; SDage = 1.57) who are at increased risk for adversity-exposure. RSA and PEP were measured during a 5-minute baseline period and 5-minute parent-child conflict discussion task. Adolescent-caregiver dyads completed a clinician-administered measure of the youth's lifetime trauma-exposure and current PTS. CAB represented the difference between RSA and PEP, while CAR was the summation of RSA and PEP. Analyses revealed that sympathetically-oriented CAB reactivity uniquely (a) indexed PTS, especially in the context of elevated trauma, and (b) distinguished between those with and without PTSD. Findings highlight the translational promise of using physiological markers that account for the balance between the parasympathetic and sympathetic nervous system.

Investigation of Acoustic Cardiographic Parameters before and after Hemodialysis.

Patients with end-stage renal disease are at an increased risk of cardiovascular diseases and associated mortality. Acoustic cardiography is a technique in which cardiac acoustic data is synchronized with electric information to detect and characterize heart sounds and detect heart failure early. The aim of this study was to investigate acoustic cardiographic parameters before and after hemodialysis (HD) and their correlations with ankle-brachial index (ABI), brachial-ankle pulse wave velocity (baPWV), and ratio of brachial preejection period to ejection time (bPEP/bET) obtained from an ABI-form device in HD patients. This study enrolled 162 HD patients between October 2016 and April 2018. Demographic, medical, and laboratory data were collected. Acoustic cardiography was performed before and after HD to assess parameters including third heart sound (S3), fourth heart sound (S4), systolic dysfunction index (SDI), electromechanical activation time (EMAT), and left ventricular systolic time (LVST). The mean age of the enrolled patients was 60.4 ± 10.9 years, and 86 (53.1%) patients were male. S4 (p < 0.001) and LVST (p < 0.001) significantly decreased after HD, but EMAT (p < 0.001) increased. Multivariate forward linear regression analysis showed that EMAT/LVST before HD was negatively associated with albumin (unstandardized coefficient β = ‐0.076; p = 0.004) and ABI (unstandardized coefficient β = ‐0.115; p = 0.011) and positively associated with bPEP/bET (unstandardized coefficient β = 0.278; p = 0.003). Screening HD patients with acoustic cardiography may help to identify patients at a high risk of malnutrition, peripheral artery disease, and left ventricular systolic dysfunction.