Increased Backward Wave Pressures Rather than Flow Explain Age-Dependent Heart Rate Effects on Central, But not Peripheral Arterial Pressure

Hypertension ◽  
2021 ◽  
Author(s):  
Nonhlanhla Mthembu ◽  
Gavin R. Norton ◽  
Vernice R. Peterson ◽  
Ravi Naran ◽  
Suraj M. Yusuf ◽  
...  
Keyword(s):  
Heart Rate ◽  
Community Sample ◽  
Characteristic Impedance ◽  
Clinical Importance ◽  
Central Pressure ◽  
Time To Peak ◽  
Relative Contribution ◽  
Filling Time ◽  
Age Dependent ◽  
The Impact

Through both backward (Pb) and forward (Pf) wave effects, a lower heart rate (HR) associates with increased central (PPc), beyond brachial pulse pressure (PP). However, the relative contribution to Pf of aortic flow (Q) versus re-reflection of Pb, has not been determined. Using central pressure, aortic velocity and diameter measurements in the outflow tract (echocardiography), we constructed central pressure waveforms that account for the relative contribution of Q versus re-reflection to Pf. We thus evaluated the mechanisms of HR-PPc relations in a community sample (n=824) and the impact of age thereon. Inverse HR-PPc ( P <0.0001), but not HR-brachial PP ( P =0.064) relations were noted. The slope of HR-PPc relation was increased in older adults ( P <0.005). HR was inversely associated with ventricular filling time, ejection duration, stroke volume, and peak Pf ( P <0.001 to P <0.0001). However, an increased Q and hence pressures generated by the product of aortic characteristic impedance and Q did not account for Pf effects. Age-dependent HR-PPc and Pf relations were both accounted for by enhanced Pb ( P <0.0001) with an increased Pf mediated by increments in wave re-reflection ( P <0.0001). The lack of impact of ejection duration on PPc was explained by an increased time to peak Pb ( P <0.0001). In conclusion, increases in PPc and Pf at a decreased HR are accounted for by an enhanced Pb rather than by a prolonged ejection or filling duration and hence flow (Q). These effects at a young-to-middle age are of little clinical significance, but at an older age, are of clinical importance.

scholarly journals Changes in left ventricular electromechanical relations during targeted hypothermia

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Kristin Wisløff-Aase ◽  
Viesturs Kerans ◽  
Kristina Haugaa ◽  
Per Steinar Halvorsen ◽  
Helge Skulstad ◽  
...  
Keyword(s):  
Heart Rate ◽  
Qt Interval ◽  
Clinical Importance ◽  
Left Ventricular ◽  
Peak Strain ◽  
Time To Peak ◽  
Mechanical Dispersion ◽  
Dispersion Of Repolarization ◽  
Aortic Valve Closure ◽  
Prolonged Qt Interval

Abstract Background Targeted hypothermia, as used after cardiac arrest, increases electrical and mechanical systolic duration. Differences in duration of electrical and mechanical systole are correlated to ventricular arrhythmias. The electromechanical window (EMW) becomes negative when the electrical systole outlasts the mechanical systole. Prolonged electrical systole corresponds to prolonged QT interval, and is associated with increased dispersion of repolarization and mechanical dispersion. These three factors predispose for arrhythmias. The electromechanical relations during targeted hypothermia are unknown. We wanted to explore the electromechanical relations during hypothermia at 33 °C. We hypothesized that targeted hypothermia would increase electrical and mechanical systolic duration without more profound EMW negativity, nor an increase in dispersion of repolarization and mechanical dispersion. Methods In a porcine model (n = 14), we registered electrocardiogram (ECG) and echocardiographic recordings during 38 °C and 33 °C, at spontaneous and atrial paced heart rate 100 beats/min. EMW was calculated by subtracting electrical systole; QT interval, from the corresponding mechanical systole; QRS onset to aortic valve closure. Dispersion of repolarization was measured as time from peak to end of the ECG T wave. Mechanical dispersion was calculated by strain echocardiography as standard deviation of time to peak strain. Results Electrical systole increased during hypothermia at spontaneous heart rate (p < 0.001) and heart rate 100 beats/min (p = 0.005). Mechanical systolic duration was prolonged and outlasted electrical systole independently of heart rate (p < 0.001). EMW changed from negative to positive value (− 20 ± 19 to 27 ± 34 ms, p = 0.001). The positivity was even more pronounced at heart rate 100 beats/min (− 25 ± 26 to 41 ± 18 ms, p < 0.001). Dispersion of repolarization decreased (p = 0.027 and p = 0.003), while mechanical dispersion did not differ (p = 0.078 and p = 0.297). Conclusion Targeted hypothermia increased electrical and mechanical systolic duration, the electromechanical window became positive, dispersion of repolarization was slightly reduced and mechanical dispersion was unchanged. These alterations may have clinical importance. Further clinical studies are required to clarify whether corresponding electromechanical alterations are accommodating in humans.

The impact of childhood trauma on psychosocial functioning and physical health in a non-clinical community sample of young adults

2019 ◽  
Vol 54 (2) ◽  
pp. 185-194
Author(s):  
Jessica Elise Beilharz ◽  
Marlee Paterson ◽  
Scott Fatt ◽  
Chloe Wilson ◽  
Alexander Burton ◽  
...  
Keyword(s):  
Heart Rate ◽  
Sleep Quality ◽  
Physical Health ◽  
Physical Abuse ◽  
Childhood Trauma ◽  
Stress Reactivity ◽  
Community Sample ◽  
Early Years ◽  
Clinical Community ◽  
The Impact

Objective: Given the fundamental emotional, social and physical development that occurs during the early years of life, childhood experiences are formative in shaping a person’s life trajectory. Childhood trauma is a prevalent, multifaceted issue with well-documented long-term adverse health effects in clinical populations however; the impact of childhood trauma in the community is less clear. To address this, this study investigated how childhood trauma may impact physical and psychological health, sleep quality and autonomic function in a non-clinical community sample of adults. Method: Participants completed questionnaires, an in-laboratory autonomic assessment (including stress reactivity to mental and physical stressors) and overnight autonomic and sleep monitoring. Overall childhood trauma and its subtypes (e.g. physical abuse, emotional neglect) were defined using the Childhood Trauma Questionnaire. Results: We identified 22 childhood trauma cases (total score > 36) and, of the 89 non-childhood trauma cases, some individuals also experienced significant levels of trauma in one or more of the childhood trauma subtypes. Childhood trauma and some trauma subtypes were significantly correlated with a myriad of negative physiological and physical health outcomes including elevated psychological distress, increased sleep disturbances, reduced emotional wellbeing and lower perceived social support. Autonomic dysregulation was found in those with high levels of childhood trauma, which was reflected in an increased stress response to laboratory tasks. Notably, the experience of physical abuse in childhood was significantly associated with alterations in nocturnal heart rate and heart rate variability. Conclusion: Together, these results highlight that childhood trauma can have lasting detrimental consequences on an individual’s emotional and physical health, sleep quality and stress reactivity.

scholarly journals Changes in Left Ventricular Electromechanical Relations During Targeted Hypothermia

2020 ◽  
Author(s):  
Kristin Wisløff-Aase ◽  
Viesturs Kerans ◽  
Kristina Haugaa ◽  
Per Steinar Halvorsen ◽  
Helge Skulstad ◽  
...  
Keyword(s):  
Heart Rate ◽  
Cardiac Arrest ◽  
Clinical Importance ◽  
Left Ventricular ◽  
Peak Strain ◽  
Time To Peak ◽  
Mechanical Dispersion ◽  
Aortic Valve Closure ◽  
Electrocardiogram Ecg ◽  
Strain Echocardiography

Abstract Background: Targeted hypothermia, as used after cardiac arrest, increases electrical and mechanical systolic duration. Differences in duration of mechanical and electrical systole are correlated to ventricular arrhythmias. The electromechanical window (EMW) becomes negative when electrical systole outlasts the mechanical systole. Prolonged electrical systole is also associated with electrical and mechanical dispersion, both predisposing for arrhythmias. The electromechanical relations during targeted hypothermia are unknown, but treatment after cardiac arrest has not demonstrated increased incidence of ventricular arrhythmic events.We wanted to explore the electromechanical relations during hypothermia at 33 °C. We hypothesized that targeted hypothermia would increase electrical and mechanical systolic duration without an increase in electromechanical negativity, nor an increase in electrical and mechanical dispersion. Methods: In a porcine model (n = 14) we registered electrocardiogram (ECG) and echocardiographic recordings during 38 °C and 33 °C, at spontaneous and atrial paced heart rate 100 beats/min. EMW was calculated by subtracting electrical systole, QT interval, from the corresponding mechanical systole, recorded from onset QRS to aortic valve closure. Electrical dispersion was measured as time from peak to end of the ECG T wave. Mechanical dispersion was calculated by strain echocardiography as standard deviation of time to peak strain. Results:Electrical systole increased during hypothermia at spontaneous heart rate (p < 0.001) and heart rate 100 beats/min (p = 0.005). Mechanical systolic duration was prolonged and outlasted electrical systole independently of heart rate (p < 0.001). EMW changed from negative to positive value (-20 ± 19 to 27 ± 34 ms, p = 0.001). The positivity was even more pronounced at heart rate 100 beats/min (-25 ± 26 to 41 ± 18 ms, p < 0.001). Electrical dispersion decreased (p = 0.027 and p = 0.003), while mechanical dispersion did not differ (p = 0.078 and p = 0.297).Conclusion: Targeted hypothermia increased electrical and mechanical systolic duration, the electromechanical window became positive, electrical dispersion was reduced and mechanical dispersion was unchanged. These alterations may have clinical importance. Further clinical studies are required to clarify whether corresponding electromechanical alterations are accommodating in humans.

Abstract 17892: Strain Rate is Affected by Heart Rate in Younger Heart: A Simultaneous Invasive and Noninvasive in vivo Piglet Model

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Etienne Fortin-Pellerin ◽  
Lisa K Hornberger ◽  
James Y Coe ◽  
Lindsay Mills ◽  
Jesus Serrano-Lomelin ◽  
...  
Keyword(s):  
Heart Rate ◽  
Strain Rate ◽  
Atrial Tachycardia ◽  
Young Infant ◽  
Left Ventricular ◽  
Baseline Heart Rate ◽  
Force Frequency ◽  
Filling Time ◽  
Frequency Relationship ◽  
The Impact

Introduction: In adult human and pig hearts, left ventricular (LV) systolic strain rate (SR) has been shown to be independent of heart rate (HR) in atrial tachycardia. It has been hypothesized that any increase in contractility related to the force-frequency relationship is balanced by a decrease in contractility due to reduced filling time and preload at higher HRs. In this study, we explore the impact of atrial tachycardia on SR of the young infant heart using a simultaneous invasive and noninvasive piglet model to determine whether SR of the immature heart is similarly not influenced by increasing HR. Methods: Under general anesthesia (propofol, isoflurane), 1 - 15 day old piglets were instrumented intravascularly with Millar high-fidelity and pacing catheters in the left ventricle and right atrium, respectively. After stabilization, invasive hemodynamic and echocardiography parameters were acquired at baseline, and at 200, 230 and 260bpm. Basal circumferential SR was analyzed off-line by speckle tracking (frame rates 247±7 Hz). Each animal was its own control and repeated measure ANOVA was used for comparison, data is expressed as mean ± SE. Results: Fourteen piglets of mean age 8.5±1.8 days, weight 3.6±0.5kg and baseline heart rate of 152±5bpm were assessed. Baseline LV systolic SR was -1.53±0.13 1/s and dP/dt 1656±115mmHg/s. With pacing, LV SR increased significantly (p = 0.002). The increase in SR mirrored the increase in contractility assessed invasively by dP/dt (p<0.001). M-mode LV end diastolic dimension decreased from baseline to 260bpm (73±9.9% of baseline value, p < 0.001) consistent with reduced preload with tachycardia. Conclusion: Our study suggests that in the younger heart, SR is augmented by atrial tachycardia itself even in the presence of decreased preload. This is in keeping with preservation of the force frequency relationship. Given our findings, HR should be taken into account when assessing contractility using SR in young patients.

scholarly journals Changes in left ventricular electromechanical relations during targeted hypothermia

2020 ◽  
Author(s):  
Kristin Wisløff-Aase ◽  
Viesturs Kerans ◽  
Kristina Haugaa ◽  
Per Steinar Halvorsen ◽  
Helge Skulstad ◽  
...  
Keyword(s):  
Heart Rate ◽  
Qt Interval ◽  
Clinical Importance ◽  
Left Ventricular ◽  
Peak Strain ◽  
Time To Peak ◽  
Mechanical Dispersion ◽  
Dispersion Of Repolarization ◽  
Aortic Valve Closure ◽  
Prolonged Qt Interval

Abstract Background:Targeted hypothermia, as used after cardiac arrest, increases electrical and mechanical systolic duration. Differences in duration of electrical and mechanical systole are correlated to ventricular arrhythmias. The electromechanical window (EMW) becomes negative when the electrical systole outlasts the mechanical systole. Prolonged electrical systole corresponds to prolonged QT interval, and is associated with increased dispersion of repolarization and mechanical dispersion. These three factors predispose for arrhythmias. The electromechanical relations during targeted hypothermia are unknown.We wanted to explore the electromechanical relations during hypothermia at 33 °C. We hypothesized that targeted hypothermia would increase electrical and mechanical systolic duration without an increase in EMW negativity, nor an increase in dispersion of repolarization and mechanical dispersion.Methods: In a porcine model (n = 14) we registered electrocardiogram (ECG) and echocardiographic recordings during 38 °C and 33 °C, at spontaneous and atrial paced heart rate 100 beats/min. EMW was calculated by subtracting electrical systole; QT interval, from the corresponding mechanical systole; QRS onset to aortic valve closure. Dispersion of repolarization was measured as time from peak to end of the ECG T wave. Mechanical dispersion was calculated by strain echocardiography as standard deviation of time to peak strain. Results:Electrical systole increased during hypothermia at spontaneous heart rate (p < 0.001) and heart rate 100 beats/min (p = 0.005). Mechanical systolic duration was prolonged and outlasted electrical systole independently of heart rate (p < 0.001). EMW changed from negative to positive value (-20 ± 19 to 27 ± 34 ms, p = 0.001). The positivity was even more pronounced at heart rate 100 beats/min (-25 ± 26 to 41 ± 18 ms, p < 0.001). Dispersion of repolarization decreased (p = 0.027 and p = 0.003), while mechanical dispersion did not differ (p = 0.078 and p = 0.297).Conclusion:Targeted hypothermia increased electrical and mechanical systolic duration, the electromechanical window became positive, dispersion of repolarization was slightly reduced and mechanical dispersion was unchanged. These alterations may have clinical importance. Further clinical studies are required to clarify whether corresponding electromechanical alterations are accommodating in humans.

Reducing the Social Stigma Associated with Obsessive Compulsive Disorder: A Controlled Trial of an Intervention Program in a Turkish Community Sample

2020 ◽  
Vol 20 (2) ◽  
pp. 101-120
Author(s):  
Ayça Aktaç Gürbüz ◽  
Orçun YORULMAZ ◽  
Gülşah DURNA
Keyword(s):  
Obsessive Compulsive Disorder ◽  
Intervention Program ◽  
Controlled Trial ◽  
Community Sample ◽  
Case Vignette ◽  
Control Group ◽  
Obsessive Compulsive ◽  
Compulsive Disorder ◽  
Significant Difference ◽  
The Impact

Scientific research into the reduction of stigmatization, particularly related to specific problems such as Obsessive-Compulsive Disorder (OCD), is scarce. In the present study, we examine the impact of a video-based antistigma intervention program for OCD in a pretest-posttest control group research. After being randomly assigned to either an intervention (n= 101) or control group (n= 96), the participants reported their attitudes on a hypothetical case vignette before and after OCD vs. Multiple Sclerosis (MS) videos, and again six months later as a follow up assessment. The mixed design analyses for the group comparisons indicated that although there was no significant difference in the measures of the control group, the participants watching the anti-stigma OCD video, in which the focus was psychoeducation and interaction strategies, reported significantly lower scores on social distances and negative beliefs for the case vignettes they read, and this difference was maintained six months later. Then, the present results indicate the effectiveness of our anti-stigma intervention program for OCD. Interventions to reduce stigmatization can also be viewed as effective tools for changing the attitudes of people toward OCD, although further research and applications are needed related to specific disorders if a longlasting impact is to be achieved.

Heart Rate and Neurological Outcomes in Patients Undergoing Targeted Temperature Management

2020 ◽  
pp. 088506662098250
Author(s):  
Chad M. Conner ◽  
William H. Perucki ◽  
Andre Gabriel ◽  
David M. O’Sullivan ◽  
Antonio B. Fernandez
Keyword(s):  
Heart Rate ◽  
Positive Association ◽  
Targeted Temperature Management ◽  
Temperature Management ◽  
Neurological Outcomes ◽  
Neurologic Outcomes ◽  
Resuscitation Guidelines ◽  
The Mean ◽  
The Impact ◽  
The Relationship

Introduction: There is a paucity of data evaluating the impact of heart rate (HR) during Targeted Temperature Management (TTM) and neurologic outcomes. Current resuscitation guidelines do not specify a HR goal during TTM. We sought to determine the relationship between HR and neurologic outcomes in a single-center registry dataset. Methods: We retrospectively studied 432 consecutive patients who completed TTM (33°C) after cardiac arrest from 2008 to 2017. We evaluated the relationship between neurologic outcomes and HR during TTM. Pittsburgh Cerebral Performance Categories (CPC) at discharge were used to determine neurological recovery. Statistical analysis included chi square, Student’s t-test and Mann-Whitney U. A logistic regression model was created to evaluate the strength of contribution of selected variables on the outcome of interest. Results: Approximately 94,000 HR data points from 432 patients were retrospectively analyzed; the mean HR was 82.17 bpm over the duration of TTM. Favorable neurological outcomes were seen in 160 (37%) patients. The mean HR in the patients with a favorable outcome was lower than the mean HR of those with an unfavorable outcome (79.98 bpm vs 85.67 bpm p < 0.001). Patients with an average HR of 60-91 bpm were 2.4 times more likely to have a favorable neurological outcome compared to than HR’s < 60 or > 91 (odds ratio [OR] = 2.36, 95% confidence interval [CI] 1.61-3.46, p < 0.001). Specifically, mean HR’s in the 73-82 bpm range had the greatest rate of favorable outcomes (OR 3.56, 95% CI 1.95-6.50), p < 0.001. Administration of epinephrine, a history of diabetes mellitus and hypertension all were associated with worse neurological outcomes independent of HR. Conclusion: During TTM, mean HRs between 60-91 showed a positive association with favorable outcomes. It is unclear whether a specific HR should be targeted during TTM or if heart rates between 60-91 bpm might be a sign of less neurological damage.

scholarly journals The impact of the Nutri-Score front-of-pack nutrition label on purchasing intentions of unprocessed and processed foods: post-hoc analyses from three randomized controlled trials

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Manon Egnell ◽  
Pilar Galan ◽  
Morgane Fialon ◽  
Mathilde Touvier ◽  
Sandrine Péneau ◽  
...  
Keyword(s):  
Randomized Controlled Trials ◽  
Low Income ◽  
P Value ◽  
Controlled Trials ◽  
Nutrition Label ◽  
Randomized Controlled ◽  
Food Purchases ◽  
Relative Contribution ◽  
Processed Products ◽  
The Impact

Abstract Background The Nutri-Score summary graded front-of-pack nutrition label has been identified as an efficient tool to increase the nutritional quality of pre-packed food purchases. However, no study has been conducted to investigate the effect of the Nutri-Score on the shopping cart composition, considering the type of foods. The present paper aims to investigate the effect of the Nutri-Score on the type of food purchases, in terms of the relative contribution of unpacked and pre-packed foods, or the processing degree of foods. Methods Between September 2016 and April 2017, three consecutive randomized controlled trials were conducted in three specific populations – students (N = 1866), low-income individuals (N = 336) and subjects suffering from cardiometabolic diseases (N = 1180) – to investigate the effect of the Nutri-Score on purchasing intentions compared to the Reference Intakes and no label. Using these combined data, the proportion of unpacked products in the shopping carts, as well as the distribution of products across food categories taking into account the degree of processing (NOVA classification) were assessed by trials arm. Results The shopping carts of participants simulating purchases with the Nutri-Score affixed on pre-packed foods contained higher proportion of unpacked products – especially raw fruits and meats, i.e. with no FoPL –, compared to participants purchasing with no label (difference of 5.93 percentage points [3.88–7.99], p-value< 0.0001) or with the Reference Intakes (difference of 5.27[3.25–7.29], p-value< 0.0001). This higher proportion was partly explained by fewer purchases of pre-packed processed and ultra-processed products overall in the Nutri-Score group. Conclusions These findings provide new insights on the positive effect of the Nutri-Score, which appears to decrease purchases in processed products resulting in higher proportions of unprocessed and unpacked foods, in line with public health recommendations.

Sign in / Sign up

Export Citation Format

Share Document