Type 2 diabetes and cardiac autonomic neuropathy screening using dynamic pupillometry

Science.gov (United States)

Lerner, Alana G.; Bernabé-Ortiz, Antonio; Ticse, Ray; Hernandez, Arturo; Huaylinos, Yvonne; Pinto, Miguel E.; Málaga, Germán; Checkley, William; Gilman, Robert H.; Miranda, J. Jaime

2015-01-01

Aim To determine if changes in pupillary response are useful as a screening tool for diabetes and to assess whether pupillometry is associated with cardiac autonomic neuropathy. Methods We conducted a cross-sectional study with participants drawn from two settings: a hospital and a community site. At the community site, individuals with newly diagnosed diabetes as well as a random sample of control individuals without diabetes, confirmed by oral glucose tolerance test, were selected. Participants underwent an LED light stimulus test and eight pupillometry variables were measured. Outcomes were diabetes, defined by oral glucose tolerance test, and cardiac autonomic dysfunction, determined by a positive readout on two of four diagnostic tests: heart rate response to the Valsalva manoeuvre; orthostatic hypotension; 30:15 ratio; and expiration-to-inspiration ratio. The area under the curve, best threshold, sensitivity and specificity of each pupillometry variable was calculated. Results Data from 384 people, 213 with diabetes, were analysed. The mean (±SD) age of the people with diabetes was 58.6 (±8.2) years and in the control subjects it was 56.1 (±8.6) years. When comparing individuals with and without diabetes, the amplitude of the pupil reaction had the highest area under the curve [0.69 (sensitivity: 78%; specificity: 55%)]. Cardiac autonomic neuropathy was present in 51 of the 138 people evaluated (37.0%; 95% CI 28.8–45.1). To diagnose cardiac autonomic neuropathy, two pupillometry variables had the highest area under the curve: baseline pupil radius [area under the curve: 0.71 (sensitivity: 51%; specificity: 84%)], and amplitude of the pupil reaction [area under the curve: 070 (sensitivity: 82%; specificity: 55%)]. Conclusions Pupillometry is an inexpensive technique to screen for diabetes and cardiac autonomic neuropathy, but it does not have sufficient accuracy for clinical use as a screening tool. PMID:25761508

Cardiac Autonomic Dysfunction in Offspring of Hypertensive Parents During Exercise.

Science.gov (United States)

Almeida, Leonardo Barbosa de; Peçanha, Tiago; Mira, Pedro Augusto de Carvalho; Souza, Livia Victorino de; da Silva, Lílian Pinto; Martinez, Daniel Godoy; Freitas, Isabelle Magalhães Guedes; Laterza, Mateus Camaroti

2017-12-01

Offspring of hypertensive parents present autonomic dysfunction at rest and during physiological maneuvers. However, the cardiac autonomic modulation during exercise remains unknown. This study tested whether the cardiac autonomic modulation would be reduced in offspring of hypertensive parents during exercise. Fourteen offspring of hypertensive and 14 offspring of normotensive individuals were evaluated. The groups were matched by age (24.5±1.0 vs. 26.6±1.5 years; p=0.25) and BMI (22.8±0.6 vs. 24.2±1.0 kg/m 2 ; p=0.30). Blood pressure and heart rate were assessed simultaneously during 3 min at baseline followed by 3-min isometric handgrip at 30% of maximal voluntary contraction. Cardiac autonomic modulation was evaluated using heart rate variability. Primary variables were subjected to two-way ANOVA (group vs. time). P valueexercise protocol. In contrast, offspring of hypertensive subjects showed a reduction of SDNN (Basal=34.8±3.5 vs. 45.2±3.7 ms; Exercise=30.8±3.3 vs. 41.5±3.9 ms; p group=0.01), RMSSD (Basal=37.1±3.7 vs. 52.0±6.0 ms; Exercise=28.6±3.4 vs. 41.9±5.3 ms; p group=0.02) and pNN50 (Basal=15.7±4.0 vs. 29.5±5.5%; Exercise=7.7±2.4 vs. 18.0±4.3%; p group=0.03) during the exercise protocol in comparison with offspring of normotensive parents. We concluded that normotensive offspring of hypertensive parents exhibit impaired cardiac autonomic modulation during exercise. © Georg Thieme Verlag KG Stuttgart · New York.

Prospective randomized controlled intervention trial: Comprehensive Yogic Breathing Improves Cardiac autonomic functions and Quality of life in Diabetes

Directory of Open Access Journals (Sweden)

V P Jyotsna

2012-01-01

Full Text Available Aims and Objectives: To assess the effect of Comprehensive Yogic Breathing Program on glycemic control, quality of life, and cardiac autonomic functions in diabetes. Material and Methods: This is a prospective randomized controlled intervention trial. Cardiac autonomic functions were assessed in 120 diabetics. Patients were randomized into two groups, one group receiving standard therapy for diabetes (n = 56 and the other group receiving standard therapy for diabetes and comprehensive yogic breathing program (n = 64. Standard therapy included advice on diet, walk, and oral antidiabetic drugs. Comprehensive yogic breathing program was an interactive session in which Sudarshan kriya yoga, a rhythmic cyclical breathing, preceded by Pranayam was taught under guidance of a certified teacher. Change in fasting, post prandial blood sugars, glycated hemoglobin, and quality of life were assessed. Cardiac autonomic function tests were done before and six months after intervention. Results: There was significant improvement in psychological (P = 0.006 and social domains (P = 0.04 and total quality of life (P = 0.02 in the group practicing comprehensive yogic breathing program as compared to the group following standard therapy alone. In the group following breathing program, the improvement in sympathetic cardiac autonomic functions was statistically significant (P = 0.01, while the change in the standard group was not significant (P = 0.17. When both parasympathetic and sympathetic cardiac autonomic functions were considered, there was a trend toward improvement in patients following comprehensive yogic breathing program (P = 0.07. In the standard therapy group, no change in cardiac autonomic functions was noted (P = 0.76. The parameters of glycemic control were comparable in both groups. Conclusion: There was significant improvement in quality of life and cardiac autonomic functions in the diabetes patients practicing comprehensive yogic breathing

Impaired cardiac uptake of meta-[123I]iodobenzylguanidine in Parkinson's disease with autonomic failure

International Nuclear Information System (INIS)

Braune, S.; Luecking, C.H.; Reinhardt, M.; Bathmann, J.; Krause, T.; Lehmann, M.

1998-01-01

Objective - To selectively investigate postganglionic sympathetic cardiac neurons in patients with Parkinson's disease and autonomic failure. Material and methods - Metaiodobenzylguanidine (MIBG) is a pharmacologically inactive analogue of noradrenaline, which is similarly metabolized in noradrenergic neurons. Therefore the uptake of radiolabelled MIBG represents not only the localization of postganglionic sympathetic neurons but also their functional integrity. Ten patients with Parkinson's disease and autonomic failure underwent standardized autonomic testing, assessment of catecholamine plasma levels and scintigraphy with [ 123 I]MIGB. Results - The cardiac uptake of MIBG, as demonstrated by the heart/mediastinum ratio, was significantly lower in patients in comparison with controls. Scintigraphy with MIBG allowed the selective in-vivo investigation of postganglionic sympathetic cardiac efferent in patients with autonomic failure, a procedure which was previously confined to post-mortem examination. Conclusion - These findings point to a relevant postganglionic pattern of involvement of the autonomic nervous system (ANS) in Parkinson's disease and autonomic failure. (au)

May a unitary autonomic index help assess autonomic cardiac regulation in elite athletes? Preliminary observations on the national Italian Olympic committee team.

Science.gov (United States)

Sala, Roberto; Malacarne, Mara; Tosi, Fabio; Benzi, Manuela; Solaro, Nadia; Tamorri, Stefano; Spataro, Antonio; Pagani, Massimo; Lucini, Daniela

2017-12-01

Long term endurance training, as occurring in elite athletes, is associated to cardiac neural remodeling in favor of cardioprotective vagal mechanisms, resulting in resting bradycardia and augmented contribution of cardiac parasympathetic nerve activity. Autonomic assessment can be performed by way of heart rate variability. This technique however provides multiple indices, and there is not yet complete agreement on their specific significance. Purpose of the study was to assess whether a rank transformation and radar plot could provide a unitary autonomic index, capable to show a correlation between intensity of individual work and quality of autonomic regulation. We studied 711 (23.6±6.2 years) elite athletes that took part in the selection procedure for the 2016 Rio Olympic Games for the National Italian Olympic Committee (CONI). Indices from Heart Rate Variability HRV obtained at rest, during standing up and during recovery from an exercise test were used to compute a percent ranked unitary autonomic index for sport (ANSIs), taken as proxy of quality of autonomic regulation. Within the observed wide range of energy expenditure, the unitary autonomic index ANSIs appears significantly correlated to individual and discipline specific training workloads (r=0.25, P<0.001 and r=0.78, P<0.001, respectively), correcting for possible age and gender bias. ANSIs also positively correlates to lipid profile. Estimated intensity of physical activity correlates with quality of cardiac autonomic regulation, as expressed by a novel unitary index of cardiac autonomic regulation. ANSIs could provide a novel and convenient approach to individual autonomic evaluation in athletes.

Impact of malnutrition on cardiac autonomic modulation in children

Directory of Open Access Journals (Sweden)

Gláucia Siqueira Carvalho Barreto

2016-11-01

Conclusion: Malnourished children present changes in cardiac autonomic modulation, characterized by reductions in both sympathetic and parasympathetic activity, as well as increased heart rate and decreased blood pressure.

Sleep restriction progress to cardiac autonomic imbalance ...

African Journals Online (AJOL)

Since it's more difficult to maintain adequate sleep duration among night watchmen during their working schedule, hence the purpose of our present study was to investigate whether mental stress or fatigue over restricted sleep period in night shift, affects HRV, in order to elucidate on cardiac autonomic modulation among ...

Music Improves Subjective Feelings Leading to Cardiac Autonomic Nervous Modulation: A Pilot Study.

Science.gov (United States)

Kume, Satoshi; Nishimura, Yukako; Mizuno, Kei; Sakimoto, Nae; Hori, Hiroshi; Tamura, Yasuhisa; Yamato, Masanori; Mitsuhashi, Rika; Akiba, Keigo; Koizumi, Jun-Ichi; Watanabe, Yasuyoshi; Kataoka, Yosky

2017-01-01

It is widely accepted that listening to music improves subjective feelings and reduces fatigue sensations, and different kinds of music lead to different activations of these feelings. Recently, cardiac autonomic nervous modulation has been proposed as a useful objective indicator of fatigue. However, scientific considerations of the relation between feelings of fatigue and cardiac autonomic nervous modulation while listening to music are still lacking. In this study, we examined which subjective feelings of fatigue are related to participants' cardiac autonomic nervous function while they listen to music. We used an album of comfortable and relaxing environmental music, with blended sounds from a piano and violin as well as natural sound sources. We performed a crossover trial of environmental music and silent sessions for 20 healthy subjects, 12 females, and 8 males, after their daily work shift. We measured changes in eight types of subjective feelings, including healing, fatigue, sleepiness, relaxation, and refreshment, using the KOKORO scale, a subjective mood measurement system for self-reported feelings. Further, we obtained measures of cardiac autonomic nervous function on the basis of heart rate variability before and after the sessions. During the music session, subjective feelings significantly shifted toward healing and a secure/relaxed feeling and these changes were greater than those in the silent session. Heart rates (ΔHR) in the music session significantly decreased compared with those in the silent session. Other cardiac autonomic parameters such as high-frequency (HF) component and the ratio of low-frequency (LF) and HF components (LF/HF) were similar in the two sessions. In the linear regression analysis of the feelings with ΔHR and changes in LF/HF (ΔLF/HF), increases and decreases in ΔHR were correlated to the feeling axes of Fatigue-Healing and Anxiety/Tension-Security/Relaxation, whereas those in ΔLF/HF were related to the feeling axes

Modulation of Cardiac Autonomic Dysfunction in Ischemic Stroke following Ayurveda (Indian System of Medicine Treatment

Directory of Open Access Journals (Sweden)

Sriranjini Sitaram Jaideep

2014-01-01

Full Text Available Objectives. Cardiac autonomic dysfunction in stroke has implications on morbidity and mortality. Ayurveda (Indian system of medicine describes stroke as pakshaghata. We intended to study the effect of Ayurveda therapies on the cardiac autonomic dysfunction. Methods. Fifty patients of ischemic stroke (middle cerebral artery territory (mean age 39.26 ± 9.88 years; male 43, female 7 were recruited within one month of ictus. All patients received standard allopathic medications as advised by neurologist. In addition, patients were randomized to receive physiotherapy (Group I or Ayurveda treatment (Group II for 14 days. Continuous electrocardiogram and finger arterial pressure were recorded for 15 min before and after treatments and analyzed offline to obtain heart rate and blood pressure variability and baroreflex sensitivity (BRS. Results were analysed by RMANOVA. Results. Patients in Group II showed statistically significant improvement in cardiac autonomic parameters. The standard deviation of normal to normal intervals,and total and low frequency powers were significantly enhanced (F=8.16, P=0.007, F=9.73, P=0.004, F=13.51, and P=0.001, resp.. The BRS too increased following the treatment period (F=10.129, P=0.004. Conclusions. The current study is the first to report a positive modulation of cardiac autonomic activity after adjuvant Ayurveda treatment in ischemic stroke. Further long term studies are warranted.

Cardiac autonomic impairment and chronotropic incompetence in fibromyalgia

OpenAIRE

da Cunha Ribeiro, Roberta Potenza; Roschel, Hamilton; Artioli, Guilherme Gianini; Dassouki, Thalita; Perandini, Luiz Augusto; Calich, Ana Luisa; de Sá Pinto, Ana Lúcia; Lima, Fernanda Rodrigues; Bonfá, Eloísa; Gualano, Bruno

2011-01-01

Abstract Introduction We aimed to gather knowledge on the cardiac autonomic modulation in patients with fibromyalgia (FM) in response to exercise and to investigate whether this population suffers from chronotropic incompetence (CI). Methods Fourteen women with FM (age: 46 ± 3 y...

Pulse wave velocity and cardiac autonomic function in type 2 diabetes mellitus.

Science.gov (United States)

Chorepsima, Stamatina; Eleftheriadou, Ioanna; Tentolouris, Anastasios; Moyssakis, Ioannis; Protogerou, Athanasios; Kokkinos, Alexandros; Sfikakis, Petros P; Tentolouris, Nikolaos

2017-05-19

Increased carotid-femoral pulse wave velocity (PWV) has been associated with incident cardiovascular disease, independently of traditional risk factors. Cardiac autonomic dysfunction is a common complication of diabetes and has been associated with reduced aortic distensibility. However, the association of cardiac autonomic dysfunction with PWV is not known. In this study we examined the association between cardiac autonomic function and PWV in subjects with type 2 diabetes mellitus. A total of 290 patients with type 2 diabetes were examined. PWV was measured at the carotid-femoral segment with applanation tonometry. Central mean arterial blood pressure (MBP) was determined by the same apparatus. Participants were classified as having normal (n = 193) or abnormal (n = 97) PWV values using age-corrected values. Cardiac autonomic nervous system activity was determined by measurement of parameters of heart rate variability (HRV). Subjects with abnormal PWV were older, had higher arterial blood pressure and higher heart rate than those with normal PWV. Most of the values of HRV were significantly lower in subjects with abnormal than in those with normal PWV. Multivariate analysis, after controlling for various confounding factors, demonstrated that abnormal PWV was associated independently only with peripheral MBP [odds ratio (OR) 1.049, 95% confidence intervals (CI) 1.015-1.085, P = 0.005], central MBP (OR 1.052, 95% CI 1.016-1.088, P = 0.004), log total power (OR 0.490, 95% CI 0.258-0.932, P = 0.030) and log high frequency power (OR 0.546, 95% CI 0.301-0.991, P = 0.047). In subjects with type 2 diabetes, arterial blood pressure and impaired cardiac autonomic function is associated independently with abnormal PWV.

The influence of midazolam on heart rate arises from cardiac autonomic tones alterations in Burmese pythons, Python molurus.

Science.gov (United States)

Lopes, Ivã Guidini; Armelin, Vinicius Araújo; Braga, Victor Hugo da Silva; Florindo, Luiz Henrique

2017-12-01

The GABA A receptor agonist midazolam is a compound widely used as a tranquilizer and sedative in mammals and reptiles. It is already known that this benzodiazepine produces small to intermediate heart rate (HR) alterations in mammals, however, its influence on reptiles' HR remains unexplored. Thus, the present study sought to verify the effects of midazolam on HR and cardiac modulation in the snake Python molurus. To do so, the snakes' HR, cardiac autonomic tones, and HR variability were evaluated during four different experimental stages. The first stage consisted on the data acquisition of animals under untreated conditions, in which were then administered atropine (2.5mgkg -1 ; intraperitoneal), followed later by propranolol (3.5mgkg -1 ; intraperitoneal) (cardiac double autonomic blockade). The second stage focused on the data acquisition of animals under midazolam effect (1.0mgkg -1 ; intramuscular), which passed through the same autonomic blockade protocol of the first stage. The third and fourth stages consisted of the same protocol of stages one and two, respectively, with the exception that atropine and propranolol injections were reversed. By comparing the HR of animals that received midazolam (second and fourth stages) with those that did not (first and third stages), it could be observed that this benzodiazepine reduced the snakes' HR by ~60%. The calculated autonomic tones showed that such cardiac depression was elicited by an ~80% decrease in cardiac adrenergic tone and an ~620% increase in cardiac cholinergic tone - a finding that was further supported by the results of HR variability analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

The ECG vertigo in diabetes and cardiac autonomic neuropathy.

Science.gov (United States)

Voulgari, Christina; Tentolouris, Nicholas; Stefanadis, Christodoulos

2011-01-01

The importance of diabetes in the epidemiology of cardiovascular diseases cannot be overemphasized. About one third of acute myocardial infarction patients have diabetes, and its prevalence is steadily increasing. The decrease in cardiac mortality in people with diabetes is lagging behind that of the general population. Cardiovascular disease is a broad term which includes any condition causing pathological changes in blood vessels, cardiac muscle or valves, and cardiac rhythm. The ECG offers a quick, noninvasive clinical and research screen for the early detection of cardiovascular disease in diabetes. In this paper, the clinical and research value of the ECG is readdressed in diabetes and in the presence of cardiac autonomic neuropathy.

Sphenopalatine ganglion stimulation induces changes in cardiac autonomic regulation in cluster headache

DEFF Research Database (Denmark)

Barloese, Mads; Petersen, Anja S; Guo, Song

2018-01-01

regulation. MATERIALS AND METHODS: In a double-blind, randomized, sham-controlled crossover design, patients received low-frequency and sham stimulation. RR intervals were recorded, and heart rate variability was analysed (time-domain, frequency-domain, nonlinear parameters). Headache characteristics......-frequency stimulation, there was a greater increase in heart rate compared to sham (Ptime domain (P...INTRODUCTION: Cluster headache is characterized by attacks of severe unilateral pain accompanied by cranial and systemic autonomic changes. Our knowledge of the latter is imperfect. This study aimed to investigate the effect of low-frequency sphenopalatine ganglion stimulation on cardiac autonomic...

The ECG Vertigo in Diabetes and Cardiac Autonomic Neuropathy

Directory of Open Access Journals (Sweden)

Christina Voulgari

2011-01-01

Full Text Available The importance of diabetes in the epidemiology of cardiovascular diseases cannot be overemphasized. About one third of acute myocardial infarction patients have diabetes, and its prevalence is steadily increasing. The decrease in cardiac mortality in people with diabetes is lagging behind that of the general population. Cardiovascular disease is a broad term which includes any condition causing pathological changes in blood vessels, cardiac muscle or valves, and cardiac rhythm. The ECG offers a quick, noninvasive clinical and research screen for the early detection of cardiovascular disease in diabetes. In this paper, the clinical and research value of the ECG is readdressed in diabetes and in the presence of cardiac autonomic neuropathy.

Resistance Training After Myocardial Infarction in Rats: Its Role on Cardiac and Autonomic Function

Directory of Open Access Journals (Sweden)

Camilla Figueiredo Grans

2014-07-01

Full Text Available Background: Although resistance exercise training is part of cardiovascular rehabilitation programs, little is known about its role on the cardiac and autonomic function after myocardial infarction. Objective: To evaluate the effects of resistance exercise training, started early after myocardial infarction, on cardiac function, hemodynamic profile, and autonomic modulation in rats. Methods: Male Wistar rats were divided into four groups: sedentary control, trained control, sedentary infarcted and trained infarcted rats. Each group with n = 9 rats. The animals underwent maximum load test and echocardiography at the beginning and at the end of the resistance exercise training (in an adapted ladder, 40% to 60% of the maximum load test, 3 months, 5 days/week. At the end, hemodynamic, baroreflex sensitivity and autonomic modulation assessments were made. Results: The maximum load test increased in groups trained control (+32% and trained infarcted (+46% in relation to groups sedentary control and sedentary infarcted. Although no change occurred regarding the myocardial infarction size and systolic function, the E/A ratio (-23%, myocardial performance index (-39% and systolic blood pressure (+6% improved with resistance exercise training in group trained infarcted. Concomitantly, the training provided additional benefits in the high frequency bands of the pulse interval (+45%, as well as in the low frequency band of systolic blood pressure (-46% in rats from group trained infarcted in relation to group sedentary infarcted. Conclusion: Resistance exercise training alone may be an important and safe tool in the management of patients after myocardial infarction, considering that it does not lead to significant changes in the ventricular function, reduces the global cardiac stress, and significantly improves the vascular and cardiac autonomic modulation in infarcted rats.

Resistance Training After Myocardial Infarction in Rats: Its Role on Cardiac and Autonomic Function

International Nuclear Information System (INIS)

Grans, Camilla Figueiredo; Feriani, Daniele Jardim; Abssamra, Marcos Elias Vergilino; Rocha, Leandro Yanase; Carrozzi, Nicolle Martins; Mostarda, Cristiano; Figueroa, Diego Mendrot; Angelis, Kátia De; Irigoyen, Maria Cláudia; Rodrigues, Bruno

2014-01-01

Although resistance exercise training is part of cardiovascular rehabilitation programs, little is known about its role on the cardiac and autonomic function after myocardial infarction. To evaluate the effects of resistance exercise training, started early after myocardial infarction, on cardiac function, hemodynamic profile, and autonomic modulation in rats. Male Wistar rats were divided into four groups: sedentary control, trained control, sedentary infarcted and trained infarcted rats. Each group with n = 9 rats. The animals underwent maximum load test and echocardiography at the beginning and at the end of the resistance exercise training (in an adapted ladder, 40% to 60% of the maximum load test, 3 months, 5 days/week). At the end, hemodynamic, baroreflex sensitivity and autonomic modulation assessments were made. The maximum load test increased in groups trained control (+32%) and trained infarcted (+46%) in relation to groups sedentary control and sedentary infarcted. Although no change occurred regarding the myocardial infarction size and systolic function, the E/A ratio (-23%), myocardial performance index (-39%) and systolic blood pressure (+6%) improved with resistance exercise training in group trained infarcted. Concomitantly, the training provided additional benefits in the high frequency bands of the pulse interval (+45%), as well as in the low frequency band of systolic blood pressure (-46%) in rats from group trained infarcted in relation to group sedentary infarcted. Resistance exercise training alone may be an important and safe tool in the management of patients after myocardial infarction, considering that it does not lead to significant changes in the ventricular function, reduces the global cardiac stress, and significantly improves the vascular and cardiac autonomic modulation in infarcted rats

Resistance Training After Myocardial Infarction in Rats: Its Role on Cardiac and Autonomic Function

Energy Technology Data Exchange (ETDEWEB)

Grans, Camilla Figueiredo; Feriani, Daniele Jardim; Abssamra, Marcos Elias Vergilino; Rocha, Leandro Yanase; Carrozzi, Nicolle Martins [Laboratório do Movimento Humano, Universidade São Judas Tadeu (USJT), São Paulo, SP (Brazil); Mostarda, Cristiano [Departamento de Educação Física, Universidade Federal do Maranhão (UFMA), São Luís, MA (Brazil); Figueroa, Diego Mendrot [Laboratório de Hipertensão Experimental, Instituto do Coração (InCor), Faculdade de Medicina, Universidade de São Paulo (USP), São Paulo, SP (Brazil); Angelis, Kátia De [Laboratório de Fisiologia Translacional, Universidade Nove de Julho (Uninove), São Paulo, SP (Brazil); Irigoyen, Maria Cláudia [Laboratório de Hipertensão Experimental, Instituto do Coração (InCor), Faculdade de Medicina, Universidade de São Paulo (USP), São Paulo, SP (Brazil); Rodrigues, Bruno, E-mail: bruno.rodrigues@incor.usp.br [Laboratório do Movimento Humano, Universidade São Judas Tadeu (USJT), São Paulo, SP (Brazil)

2014-07-15

Although resistance exercise training is part of cardiovascular rehabilitation programs, little is known about its role on the cardiac and autonomic function after myocardial infarction. To evaluate the effects of resistance exercise training, started early after myocardial infarction, on cardiac function, hemodynamic profile, and autonomic modulation in rats. Male Wistar rats were divided into four groups: sedentary control, trained control, sedentary infarcted and trained infarcted rats. Each group with n = 9 rats. The animals underwent maximum load test and echocardiography at the beginning and at the end of the resistance exercise training (in an adapted ladder, 40% to 60% of the maximum load test, 3 months, 5 days/week). At the end, hemodynamic, baroreflex sensitivity and autonomic modulation assessments were made. The maximum load test increased in groups trained control (+32%) and trained infarcted (+46%) in relation to groups sedentary control and sedentary infarcted. Although no change occurred regarding the myocardial infarction size and systolic function, the E/A ratio (-23%), myocardial performance index (-39%) and systolic blood pressure (+6%) improved with resistance exercise training in group trained infarcted. Concomitantly, the training provided additional benefits in the high frequency bands of the pulse interval (+45%), as well as in the low frequency band of systolic blood pressure (-46%) in rats from group trained infarcted in relation to group sedentary infarcted. Resistance exercise training alone may be an important and safe tool in the management of patients after myocardial infarction, considering that it does not lead to significant changes in the ventricular function, reduces the global cardiac stress, and significantly improves the vascular and cardiac autonomic modulation in infarcted rats.

Resistance Training After Myocardial Infarction in Rats: Its Role on Cardiac and Autonomic Function

Science.gov (United States)

Grans, Camilla Figueiredo; Feriani, Daniele Jardim; Abssamra, Marcos Elias Vergilino; Rocha, Leandro Yanase; Carrozzi, Nicolle Martins; Mostarda, Cristiano; Figueroa, Diego Mendrot; Angelis, Kátia De; Irigoyen, Maria Cláudia; Rodrigues, Bruno

2014-01-01

Background Although resistance exercise training is part of cardiovascular rehabilitation programs, little is known about its role on the cardiac and autonomic function after myocardial infarction. Objective To evaluate the effects of resistance exercise training, started early after myocardial infarction, on cardiac function, hemodynamic profile, and autonomic modulation in rats. Methods Male Wistar rats were divided into four groups: sedentary control, trained control, sedentary infarcted and trained infarcted rats. Each group with n = 9 rats. The animals underwent maximum load test and echocardiography at the beginning and at the end of the resistance exercise training (in an adapted ladder, 40% to 60% of the maximum load test, 3 months, 5 days/week). At the end, hemodynamic, baroreflex sensitivity and autonomic modulation assessments were made. Results The maximum load test increased in groups trained control (+32%) and trained infarcted (+46%) in relation to groups sedentary control and sedentary infarcted. Although no change occurred regarding the myocardial infarction size and systolic function, the E/A ratio (-23%), myocardial performance index (-39%) and systolic blood pressure (+6%) improved with resistance exercise training in group trained infarcted. Concomitantly, the training provided additional benefits in the high frequency bands of the pulse interval (+45%), as well as in the low frequency band of systolic blood pressure (-46%) in rats from group trained infarcted in relation to group sedentary infarcted. Conclusion Resistance exercise training alone may be an important and safe tool in the management of patients after myocardial infarction, considering that it does not lead to significant changes in the ventricular function, reduces the global cardiac stress, and significantly improves the vascular and cardiac autonomic modulation in infarcted rats. PMID:25014059

The autonomic nervous system and cardiac GLP-1 receptors control heart rate in mice

Directory of Open Access Journals (Sweden)

Laurie L. Baggio

2017-11-01

Conclusions: GLP-1R agonists increase HR through multiple mechanisms, including regulation of autonomic nervous system function, and activation of the atrial GLP-1R. Surprisingly, the isolated atrial GLP-1R does not transduce a direct chronotropic effect following exposure to GLP-1R agonists in the intact heart, or isolated atrium, ex vivo. Hence, cardiac GLP-1R circuits controlling HR require neural inputs and do not function in a heart-autonomous manner.

Influence of classic massage on cardiac autonomic modulation

Directory of Open Access Journals (Sweden)

Mário Augusto Paschoal

Full Text Available Abstract Introduction: Massage can be defined as the rhythmic and smooth manipulation of body tissues, with the aim to promote health and well-being. Objective: To assess the influence of classic massage on cardiac autonomic modulation. Methods: Cross-sectional study that evaluated healthy participants, with mean age between 18 and 25 years, divided into two groups: test group (TG, n=11 and control group (CG, n=10. The TG had their heartbeat recorded for 5min before receiving a classic massage for 40min and during three periods after this procedure: 0-5min, 5-10min and 10-15min. The CG had their heartbeats recorded at the same time; without receive massage. Cardiac autonomic modulation was investigated by heart rate variability (HRV. Results: The mean values of HRV rates were: pNN50, respectively, for the TG: before massage (10.5 ± 9.5%, and after massage: 0-5min (11.6 ± 7.2%, 5-10min (12.1 ± 8.0% and 10-15min (11.1 ± 7.9%, with no significant statistical difference. The same result was found for the mean values of rMSSD index of the TG; before massage: 52.1 ± 46.2 ms, and after massage: 0-5min (50.0 ± 21.6ms, 5-10min (52.0 ± 27.4 ms and 10-15min (48.2 ± 21.1 ms. Also, the values of LFnuand HFnu indexes did not change significantly before and after massage, and they were not statistically different from the values presented by the control group. Conclusion: The study results suggest that one session of classic massage does not modify cardiac autonomic modulation in healthy young adults.

Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control.

Science.gov (United States)

Kember, Guy; Ardell, Jeffrey L; Shivkumar, Kalyanam; Armour, J Andrew

2017-01-01

The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as 'free-floating' in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease.

Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control

Science.gov (United States)

Ardell, Jeffrey L.; Shivkumar, Kalyanam; Armour, J. Andrew

2017-01-01

The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as ‘free-floating’ in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease. PMID:28692680

Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control.

Directory of Open Access Journals (Sweden)

Guy Kember

Full Text Available The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as 'free-floating' in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease.

Diabetic cardiac autonomic dysfunction. Parasympathetic versus sympathetic

International Nuclear Information System (INIS)

Uehara, Akihiko; Kurata, Chinori; Sugi, Toshihiko; Mikami, Tadashi; Shouda, Sakae

1999-01-01

Diabetic cardiac autonomic dysfunction often causes lethal arrhythmia and sudden cardiac death. 123 I-Metaiodobenzylguanidine (MIBG) can evaluate cardiac sympathetic dysfunction, and analysis of heart rate variability (HRV) can reflect cardiac parasympathetic activity. We examined whether cardiac parasympathetic dysfunction assessed by HRV may correlate with sympathetic dysfunction assessed by MIBG in diabetic patients. In 24-hour electrocardiography, we analyzed 4 HRV parameters: high-frequency power (HF), HF in the early morning (EMHF), rMSSD and pNN50. MIBG planar images and SPECT were obtained 15 minutes (early) and 150 minutes (late) after injection and the heart washout rate was calculated. The defect score in 9 left ventricular regions was scored on a 4 point scale (0=normal - 3=severe defect). In 20 selected diabetic patients without congestive heart failure, coronary artery disease and renal failure, parasympathetic HRV parameters had a negative correlation with the sum of defect scores (DS) in the late images (R=-0.47 to -0.59, p<0.05) and some parameters had a negative correlation with the washout rate (R=-0.50 to -0.55, p<0.05). In a total of 64 diabetic patients also, these parameters had a negative correlation with late DS (R=-0.28 to -0.35, p<0.05) and early DS (R=-0.27 to -0.32, p<0.05). The progress of diabetic cardiac parasympathetic dysfunction may parallel the sympathetic one. (author)

Cardiac Autonomic Function Is Associated With the Coronary Microcirculatory Function in Patients With Type 2 Diabetes

DEFF Research Database (Denmark)

von Scholten, Bernt Johan; Hansen, Christian Stevns; Hasbak, Philip

2016-01-01

Cardiac autonomic dysfunction and cardiac microvascular dysfunction are diabetic complications associated with increased mortality, but the association between these has been difficult to assess. We applied new and sensitive methods to assess this in patients with type 2 diabetes mellitus (T2DM......). In a cross-sectional design, coronary flow reserve (CFR) assessed by cardiac (82)Rb-positron emission tomography/computed tomography, cardiac autonomic reflex tests, and heart rate variability indices were performed in 55 patients with T2DM, without cardiovascular disease, and in 28 control subjects. Cardiac....... A heart rate variability index, reflecting sympathetic and parasympathetic function (low-frequency power), and the late heart-to-mediastinum ratio, reflecting the function of adrenergic receptors and sympathetic activity, were positively correlated with CFR after adjustment for age and heart rate...

Cardiac autonomic responses induced by mental tasks and the influence of musical auditory stimulation.

Science.gov (United States)

Barbosa, Juliana Cristina; Guida, Heraldo L; Fontes, Anne M G; Antonio, Ana M S; de Abreu, Luiz Carlos; Barnabé, Viviani; Marcomini, Renata S; Vanderlei, Luiz Carlos M; da Silva, Meire L; Valenti, Vitor E

2014-08-01

We investigated the acute effects of musical auditory stimulation on cardiac autonomic responses to a mental task in 28 healthy men (18-22 years old). In the control protocol (no music), the volunteers remained at seated rest for 10 min and the test was applied for five minutes. After the end of test the subjects remained seated for five more minutes. In the music protocol, the volunteers remained at seated rest for 10 min, then were exposed to music for 10 min; the test was then applied over five minutes, and the subjects remained seated for five more minutes after the test. In the control and music protocols the time domain and frequency domain indices of heart rate variability remained unchanged before, during and after the test. We found that musical auditory stimulation with baroque music did not influence cardiac autonomic responses to the mental task. Copyright © 2014 Elsevier Ltd. All rights reserved.

Screening for diabetic cardiac autonomic neuropathy using a new handheld device

DEFF Research Database (Denmark)

Gulichsen, Elisabeth; Fleischer, Jesper; Ejskjaer, Niels

2012-01-01

Cardiac autonomic neuropathy (CAN) is a serious complication of longstanding diabetes and is associated with an increased morbidity and reduced quality of life in patients with diabetes. The present study evaluated the prevalence of CAN diagnosed by reduced heart rate variability (HRV) using a ne...

Percutaneous autonomic neural modulation: A novel technique to treat cardiac arrhythmia

International Nuclear Information System (INIS)

DeSimone, Christopher V.; Madhavan, Malini; Venkatachalam, Kalpathi L.; Knudson, Mark B.; Asirvatham, Samuel J.

2013-01-01

Ablation and anti-arrhythmic medications have shown promise but have been met with varying success and unwanted side effects such as myocardial injury, arrhythmias, and morbidity from invasive surgical intervention. The answer to improving efficacy of ablation may include modulation of the cardiac aspect of the autonomic nervous system. Our lab has developed a novel approach and device to navigate the oblique sinus and to use DC current and saline/alcohol irrigation to selectively stimulate and block the autonomic ganglia found on the epicardial side of the heart. This novel approach minimizes myocardial damage from thermal injury and provides a less invasive and targeted approach. For feasibility, proof-of-concept, and safety monitoring, we carried out canine studies to test this novel application. Our results suggest a safer and less invasive way of modulating arrhythmogenic substrate that may lead to improved treatment of AF in humans

Percutaneous autonomic neural modulation: A novel technique to treat cardiac arrhythmia

Energy Technology Data Exchange (ETDEWEB)

DeSimone, Christopher V.; Madhavan, Malini [Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN (United States); Venkatachalam, Kalpathi L. [Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Jacksonville, FL (United States); Knudson, Mark B. [Mayo Clinic, Rochester, MN (United States); EnteroMedics, EnteroMedics, St. Paul, MN (United States); Asirvatham, Samuel J., E-mail: asirvatham.samuel@mayo.edu [Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN (United States); Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN (United States)

2013-05-15

Ablation and anti-arrhythmic medications have shown promise but have been met with varying success and unwanted side effects such as myocardial injury, arrhythmias, and morbidity from invasive surgical intervention. The answer to improving efficacy of ablation may include modulation of the cardiac aspect of the autonomic nervous system. Our lab has developed a novel approach and device to navigate the oblique sinus and to use DC current and saline/alcohol irrigation to selectively stimulate and block the autonomic ganglia found on the epicardial side of the heart. This novel approach minimizes myocardial damage from thermal injury and provides a less invasive and targeted approach. For feasibility, proof-of-concept, and safety monitoring, we carried out canine studies to test this novel application. Our results suggest a safer and less invasive way of modulating arrhythmogenic substrate that may lead to improved treatment of AF in humans.

Factors influencing the role of cardiac autonomic regulation in the service of cognitive control.

Science.gov (United States)

Capuana, Lesley J; Dywan, Jane; Tays, William J; Elmers, Jamie L; Witherspoon, Richelle; Segalowitz, Sidney J

2014-10-01

Working from a model of neurovisceral integration, we examined whether adding response contingencies and motivational involvement would increase the need for cardiac autonomic regulation in maintaining effective cognitive control. Respiratory sinus arrhythmia (RSA) was recorded during variants of the Stroop color-word task. The Basic task involved "accepting" congruent items and "rejecting" words printed in incongruent colors (BLUE in red font); an added contingency involved rejecting a particular congruent word (e.g., RED in red font), or a congruent word repeated on an immediately subsequent trial. Motivation was increased by adding a financial incentive phase. Results indicate that pre-task RSA predicted accuracy best when response contingencies required the maintenance of a specific item in memory or on the Basic Stroop task when errors resulted in financial loss. Overall, RSA appeared to be most relevant to performance when the task encouraged a more proactive style of cognitive control, a control strategy thought to be more metabolically costly, and hence, more reliant on flexible cardiac autonomic regulation. Copyright © 2014 Elsevier B.V. All rights reserved.

Influences of lifestyle factors on cardiac autonomic nervous system activity over time

NARCIS (Netherlands)

Hu, Mandy Xian; Lamers, Femke; de Geus, Eco J C; Penninx, Brenda W J H

Physical activity, alcohol use and smoking might affect cardiovascular disease through modifying autonomic nervous system (ANS) activity. We investigated: 1) whether there are consistent relationships between lifestyle factors and cardiac ANS activity over time, and 2) whether 2-year changes in

Cardiac autonomic regulation during exposure to auditory stimulation with classical baroque or heavy metal music of different intensities.

Science.gov (United States)

Amaral, Joice A T; Nogueira, Marcela L; Roque, Adriano L; Guida, Heraldo L; De Abreu, Luiz Carlos; Raimundo, Rodrigo Daminello; Vanderlei, Luiz Carlos M; Ribeiro, Vivian L; Ferreira, Celso; Valenti, Vitor E

2014-03-01

The effects of chronic music auditory stimulation on the cardiovascular system have been investigated in the literature. However, data regarding the acute effects of different styles of music on cardiac autonomic regulation are lacking. The literature has indicated that auditory stimulation with white noise above 50 dB induces cardiac responses. We aimed to evaluate the acute effects of classical baroque and heavy metal music of different intensities on cardiac autonomic regulation. The study was performed in 16 healthy men aged 18-25 years. All procedures were performed in the same soundproof room. We analyzed heart rate variability (HRV) in time (standard deviation of normal-to-normal R-R intervals [SDNN], root-mean square of differences [RMSSD] and percentage of adjacent NN intervals with a difference of duration greater than 50 ms [pNN50]) and frequency (low frequency [LF], high frequency [HF] and LF/HF ratio) domains. HRV was recorded at rest for 10 minutes. Subsequently, the volunteers were exposed to one of the two musical styles (classical baroque or heavy metal music) for five minutes through an earphone, followed by a five-minute period of rest, and then they were exposed to the other style for another five minutes. The subjects were exposed to three equivalent sound levels (60-70dB, 70-80dB and 80-90dB). The sequence of songs was randomized for each individual. Auditory stimulation with heavy metal music did not influence HRV indices in the time and frequency domains in the three equivalent sound level ranges. The same was observed with classical baroque musical auditory stimulation with the three equivalent sound level ranges. Musical auditory stimulation of different intensities did not influence cardiac autonomic regulation in men.

Cardiac arrest after anesthetic management in a patient with hereditary sensory autonomic neuropathy type IV

Directory of Open Access Journals (Sweden)

Yakup Ergül

2011-01-01

Full Text Available Hereditary sensory autonomic neuropathy type IV is a rare disorder with an autosomal recessive transmission and characterized by self-mutilation due to a lack in pain and heat sensation. Recurrent hyperpyrexia and anhydrosis are seen in patients as a result of a lack of sweat gland innervation. Self-mutilation and insensitivity to pain result in orthopedic complications and patients undergone recurrent surgical interventions with anesthesia. However, these patients are prone to perioperative complications such as hyperthermia, hypothermia, and cardiac complications like bradycardia and hypotension. We report a 5-year-old boy with hereditary sensory autonomic neuropathy type IV, developing hyperpyrexia and cardiac arrest after anesthesia.

Cardiac arrest after anesthetic management in a patient with hereditary sensory autonomic neuropathy type IV.

Science.gov (United States)

Ergül, Yakup; Ekici, Bariş; Keskin, Sabiha

2011-01-01

Hereditary sensory autonomic neuropathy type IV is a rare disorder with an autosomal recessive transmission and characterized by self-mutilation due to a lack in pain and heat sensation. Recurrent hyperpyrexia and anhydrosis are seen in patients as a result of a lack of sweat gland innervation. Self-mutilation and insensitivity to pain result in orthopedic complications and patients undergone recurrent surgical interventions with anesthesia. However, these patients are prone to perioperative complications such as hyperthermia, hypothermia, and cardiac complications like bradycardia and hypotension. We report a 5-year-old boy with hereditary sensory autonomic neuropathy type IV, developing hyperpyrexia and cardiac arrest after anesthesia.

Glycemic Variability Is Associated With Reduced Cardiac Autonomic Modulation in Women With Type 2 Diabetes

DEFF Research Database (Denmark)

Fleischer, Jesper; Lebech Cichosz, Simon; Hoeyem, Pernille

2015-01-01

OBJECTIVE: To investigate the sex differences in cardiac autonomic modulation in patients with newly diagnosed type 2 diabetes and to determine whether cardiac autonomic modulation is associated with glycemic variability. RESEARCH DESIGN AND METHODS: We investigated a cohort consisting of 48 men...... and 39 women with non-insulin-treated type 2 diabetes and a known duration of diabetes ... by the standard deviation of normal-to-normal intervals (P = 0.001), the root mean square of successive differences (P = 0.018), LF (P power (P = 0.008), RS ratio (P = 0.027), and expiration-to-inspiration ratio (P = 0.006) was significantly associated with increased glycemic...

Cardiac autonomic regulation is disturbed in children with euthyroid Hashimoto thyroiditis.

Science.gov (United States)

Kilic, Ayhan; Gulgun, Mustafa; Tascilar, Mehmet Emre; Sari, Erkan; Yokusoglu, Mehmet

2012-03-01

Hashimoto thyroiditis (chronic autoimmune thyroiditis) is the most common form of thyroiditis in childhood. Previous studies have found autonomic dysfunction of varying magnitude in patients with autoimmune diseases, which is considered a cardiovascular risk factor. We aimed to evaluate the heart rate variability (HRV), a measure of cardiac autonomic modulation, in children with euthyroid Hashimoto thyroiditis (eHT). The study included 32 patients with eHT (27 girls and 5 boys; mean age 11 ± 4.1 years, range 8-16; body mass index 0.47 ± 0.69 kg/m(2)), as judged by normal or minimally elevated serum TSH levels (normal range: 0.34-5.6 mIU/l) and normal levels of free thyroid hormones (FT4 and FT3) and 38 euthyroid age-matched controls. Patients with eHT and control subjects underwent physical examination and 24-hour ambulatory ECG monitoring. Time-domain parameters of HRV were evaluated for cardiac autonomic functions. Children with eHT displayed significantly lower values of time-domain parameters of SDANN (standard deviation of the averages of NN intervals), RMSSD (square root of the mean of the sum of the squares of differences between adjacent NN intervals), NN50 counts (number of pairs of adjacent NN intervals differing by more than 50 ms) and PNN50 (NN50 count divided by the total number of all NN intervals) for each 5-min interval, compared to healthy controls (p < 0.05 for each), indicating the decreased beat-to-beat variation of heart rate. In conclusion, eHT is associated with disturbed autonomic regulation of heart rate. Hence, the children with eHT are at higher risk for developing cardiovascular diseases.

Cardiac Autonomic Function during Submaximal Treadmill Exercise in Adults with Down Syndrome

Science.gov (United States)

Mendonca, Goncalo V.; Pereira, Fernando D.; Fernhall, Bo

2011-01-01

This study determined whether the cardiac autonomic function of adults with Down syndrome (DS) differs from that of nondisabled persons during submaximal dynamic exercise. Thirteen participants with DS and 12 nondisabled individuals performed maximal and submaximal treadmill tests with metabolic and heart rate (HR) measurements. Spectral analysis…

Cardiac autonomic impairment and chronotropic incompetence in fibromyalgia.

Science.gov (United States)

da Cunha Ribeiro, Roberta Potenza; Roschel, Hamilton; Artioli, Guilherme Gianini; Dassouki, Thalita; Perandini, Luiz Augusto; Calich, Ana Luisa; de Sá Pinto, Ana Lúcia; Lima, Fernanda Rodrigues; Bonfá, Eloísa; Gualano, Bruno

2011-01-01

We aimed to gather knowledge on the cardiac autonomic modulation in patients with fibromyalgia (FM) in response to exercise and to investigate whether this population suffers from chronotropic incompetence (CI). Fourteen women with FM (age: 46 ± 3 years; body mass index (BMI): 26.6 ± 1.4 kg/m2) and 14 gender-, BMI- (25.4 ± 1.3 kg/m2), and age-matched (age: 41 ± 4 years) healthy individuals (CTRL) took part in this cross-sectional study. A treadmill cardiorespiratory test was performed and heart-rate (HR) response during exercise was evaluated by the chronotropic reserve. HR recovery (deltaHRR) was defined as the difference between HR at peak exercise and at both first (deltaHRR1) and second (deltaHRR2) minutes after the exercise test. FM patients presented lower maximal oxygen consumption (VO2 max) when compared with healthy subjects (22 ± 1 versus CTRL: 32 ± 2 mL/kg/minute, respectively; P < 0.001). Additionally, FM patients presented lower chronotropic reserve (72.5 ± 5 versus CTRL: 106.1 ± 6, P < 0.001), deltaHRR1 (24.5 ± 3 versus CTRL: 32.6 ± 2, P = 0.059) and deltaHRR2 (34.3 ± 4 versus CTRL: 50.8 ± 3, P = 0.002) than their healthy peers. The prevalence of CI was 57.1% among patients with FM. Patients with FM who undertook a graded exercise test may present CI and delayed HR recovery, both being indicative of cardiac autonomic impairment and higher risk of cardiovascular events and mortality.

Simvastatin-induced cardiac autonomic control improvement in fructose-fed female rats

Directory of Open Access Journals (Sweden)

Renata Juliana da Silva

2011-01-01

Full Text Available OBJECTIVE: Because autonomic dysfunction has been found to lead to cardiometabolic disorders and because studies have reported that simvastatin treatment has neuroprotective effects, the objective of the present study was to investigate the effects of simvastatin treatment on cardiovascular and autonomic changes in fructose-fed female rats. METHODS: Female Wistar rats were divided into three groups: controls (n=8, fructose (n=8, and fructose+ simvastatin (n=8. Fructose overload was induced by supplementing the drinking water with fructose (100 mg/L, 18 wks. Simvastatin treatment (5 mg/kg/day for 2 wks was performed by gavage. The arterial pressure was recorded using a data acquisition system. Autonomic control was evaluated by pharmacological blockade. RESULTS: Fructose overload induced an increase in the fasting blood glucose and triglyceride levels and insulin resistance. The constant rate of glucose disappearance during the insulin intolerance test was reduced in the fructose group (3.4+ 0.32%/min relative to that in the control group (4.4+ 0.29%/min. Fructose+simvastatin rats exhibited increased insulin sensitivity (5.4+0.66%/min. The fructose and fructose+simvastatin groups demonstrated an increase in the mean arterial pressure compared with controls rats (fructose: 124+2 mmHg and fructose+simvastatin: 126 + 3 mmHg vs. controls: 112 + 2 mmHg. The sympathetic effect was enhanced in the fructose group (73 + 7 bpm compared with that in the control (48 + 7 bpm and fructose+simvastatin groups (31+8 bpm. The vagal effect was increased in fructose+simvastatin animals (84 + 7 bpm compared with that in control (49 + 9 bpm and fructose animals (46+5 bpm. CONCLUSION: Simvastatin treatment improved insulin sensitivity and cardiac autonomic control in an experimental model of metabolic syndrome in female rats. These effects were independent of the improvements in the classical plasma lipid profile and of reductions in arterial pressure. These results

Effects of psychological stress test on the cardiac response of public safety workers: alternative parameters to autonomic balance

Science.gov (United States)

Huerta-Franco, M. R.; Vargas-Luna, F. M.; Delgadillo-Holtfort, I.

2015-01-01

It is well known that public safety workers (PSW) face many stressful situations that yield them as high-risk population for suffering chronic stress diseases. In this multidisciplinary research the cardiac response to induced psychological stress by a short duration Stroop test was evaluated in 20 female and 19 male PSW, in order to compare traditionally used cardiac response parameters with alternative ones. Electrocardiograms have been recorded using the Eindhoven electrodes configuration for 1 min before, 3 min during and 1 min after the test. Signals analysis has been performed for the heart rate and the power spectra of its variability and of the variability of the amplitude of the R-wave, i.e. the highest peak of the electrocardiographic signal periodic sequence. The results demonstrated that the traditional autonomic balance index shows no significant differences between stages. In contrast, the median of the area of the power spectrum of the R-wave amplitude variability in the frequency region dominated by the autonomous nervous system (0.04-to-0.4 Hz) is the more sensitive parameter. Moreover, this parameter allows to identify gender differences consistent with those encountered in other studies.

Effects of psychological stress test on the cardiac response of public safety workers: alternative parameters to autonomic balance

International Nuclear Information System (INIS)

Huerta-Franco, M R; Vargas-Luna, F M; Delgadillo-Holtfort, I

2015-01-01

It is well known that public safety workers (PSW) face many stressful situations that yield them as high-risk population for suffering chronic stress diseases. In this multidisciplinary research the cardiac response to induced psychological stress by a short duration Stroop test was evaluated in 20 female and 19 male PSW, in order to compare traditionally used cardiac response parameters with alternative ones. Electrocardiograms have been recorded using the Eindhoven electrodes configuration for 1 min before, 3 min during and 1 min after the test. Signals analysis has been performed for the heart rate and the power spectra of its variability and of the variability of the amplitude of the R-wave, i.e. the highest peak of the electrocardiographic signal periodic sequence. The results demonstrated that the traditional autonomic balance index shows no significant differences between stages. In contrast, the median of the area of the power spectrum of the R-wave amplitude variability in the frequency region dominated by the autonomous nervous system (0.04-to-0.4 Hz) is the more sensitive parameter. Moreover, this parameter allows to identify gender differences consistent with those encountered in other studies

Cardiac autonomic control in adolescents with primary hypertension

Directory of Open Access Journals (Sweden)

Havlíceková Z

2009-12-01

Full Text Available Abstract Background Impairment in cardiovascular autonomic regulation participates in the onset and maintenance of primary hypertension. Objective The aim of the present study was to evaluate cardiac autonomic control using long-term heart rate variability (HRV analysis in adolescents with primary hypertension. Subjects and methods Twenty two adolescent patients with primary hypertension (5 girls/17 boys aged 14-19 years and 22 healthy subjects matched for age and gender were enrolled. Two periods from 24-hour ECG recording were evaluated by HRV analysis: awake state and sleep. HRV analysis included spectral power in low frequency band (LF, in high frequency band (HF, and LF/HF ratio. Results In awake state, adolescents with primary hypertension had lower HF and higher LF and LF/HF ratio. During sleep, HF was lower and LF/HF ratio was higher in patients with primary hypertension. Conclusions A combination of sympathetic predominance and reduced vagal activity might represent a potential link between psychosocial factors and primary hypertension, associated with increased cardiovascular morbidity.

The association between depressive disorder and cardiac autonomic control in adults 60 years and older.

Science.gov (United States)

Licht, Carmilla M M; Naarding, Paul; Penninx, Brenda W J H; van der Mast, Roos C; de Geus, Eco J C; Comijs, Hannie

2015-04-01

Altered cardiac autonomic control has often been reported in depressed persons and might play an important role in the increased risk for cardiovascular disease (CVD). A negative association between cardiac autonomic control and depression might become specifically clinically relevant in persons 60 years or older as CVD risk increases with age. This study included data of 321 persons with a depressive disorder and 115 controls participating in the Netherlands Study of Depression in Older Persons (mean age = 70.3 years, 65.7% female). Respiratory sinus arrhythmia (RSA), heart rate (HR), and preejection period (PEP) were measured and compared between depressed persons and controls. In addition, the role of antidepressants and clinical characteristics (e.g., age of depression onset and comorbid anxiety) was examined. Compared with controls, depressed persons had lower RSA (mean [standard error of the mean] = 23.5 [1.2] milliseconds versus 18.6 [0.7] milliseconds, p = .001, d = 0.373) and marginally higher HR (73.1 [1.1] beats/min versus 75.6 [0.6] beats/min, p = .065, d = 0.212), but comparable PEP (113.9 [2.1] milliseconds versus 112.0 [1.2] milliseconds, p = .45, d = 0.087), fully adjusted. Antidepressants strongly attenuated the associations between depression and HR and RSA. Antidepressant-naïve depressed persons had similar HR and RSA to controls, whereas users of antidepressants showed significantly lower RSA. In addition, tricyclic antidepressant users had higher HR (p 768) and shorter PEP (p = .014, d = 0.395) than did controls. Depression was not associated with cardiac autonomic control, but antidepressants were in this sample. All antidepressants were associated with low cardiac parasympathetic control and specifically tricyclic antidepressants with high cardiac sympathetic control.

Gross anatomical study on the human myocardial bridges with special reference to the spatial relationship among coronary arteries, cardiac veins, and autonomic nerves.

Science.gov (United States)

Watanabe, Yuko; Arakawa, Takamitsu; Kageyama, Ikuo; Aizawa, Yukio; Kumaki, Katsuji; Miki, Akinori; Terashima, Toshio

2016-04-01

Coronary arteries are frequently covered by cardiac muscles. This arrangement is termed a myocardial bridge. Previous studies have shown that myocardial bridges can cause myocardial ischemic diseases or cardiac arrhythmia, but the relevant pathogenic mechanisms remain unknown. We examined 60 hearts from Japanese cadavers macroscopically to clarify the spatial relationships among coronary arteries, cardiac veins and autonomic nerves. We found 86 myocardial bridges in 47 hearts from the 60 cadavers examined (78.3%). Next, we dissected out nine hearts with myocardial bridges in detail under the operating microscope. We found no additional branches of coronary arteries on the myocardial bridge surfaces. However, the cardiac veins, which usually accompany the coronary arteries, ran independently on the myocardial bridge surfaces in the same region. Cardiac autonomic nerves comprised two rami: one was associated with the coronary artery under the myocardial bridge and the other ran on the surface of the bridge. Such spatial relationships among the coronary arteries, cardiac veins and cardiac autonomic nerves at the myocardial bridges are quite similar to those in mouse embryo hearts. © 2015 Wiley Periodicals, Inc.

Evaluation of cardiac autonomic function in overweight males: A cross-sectional study

Directory of Open Access Journals (Sweden)

Debasish Das

2017-01-01

Full Text Available Background and Aim: Cardiovascular autonomic function tests (CAFTs are non-invasive tests that can assess both sympathetic and parasympathetic autonomic functions. Autonomic dysfunction may be considered as a risk factor for obesity and vice versa. For measurement of obesity, body mass index (BMI is a simple, valid and inexpensive method. Hence, this study was designed to evaluate the effect of obesity based on BMI criteria on autonomic nervous system based on CAFT in young adult males. Methods: A cross-sectional study was carried out on 43 young adult males in the age group of 18–25 years with an age-matched control (n = 43 group. After initial screening, anthropometric measurements were recorded. CAFTs were performed and recorded by the Cardiac Autonomic Neuropathy Analysis System (CANWin. Unpaired t- test was done to compare the parameters of study and control groups in Microsoft Excel® 2010. Results: Parasympathetic test parameters of study and control groups when expressed in mean ± standard deviation were not found statistically significant (P > 0.05. The fall in systolic blood pressure (BP in orthostatic test of study group (12.19 ± 4.8 mmHg was significantly (P = 0.0001 higher than that of control group (7.33 ± 5.16 mmHg. Increase in diastolic BP in isometric handgrip exercise test of study group (11.84 ± 5.39 mmHg was significantly less (P = 0.004 than that of control group (16.39 ± 8.71 mmHg. Conclusion: Overweight young males have altered sympathetic activity but parasympathetic activity did not show any significant difference when compared to normal weight males.

Quantity and Quality of Carbohydrate Intake during Pregnancy, Newborn Body Fatness and Cardiac Autonomic Control: Conferred Cardiovascular Risk?

Directory of Open Access Journals (Sweden)

Kirsty M. Mckenzie

2017-12-01

Full Text Available The fetal environment has an important influence on health and disease over the life course. Maternal nutritional status during pregnancy is potentially a powerful contributor to the intrauterine environment, and may alter offspring physiology and later life cardio-metabolic risk. Putative early life markers of cardio-metabolic risk include newborn body fatness and cardiac autonomic control. We sought to determine whether maternal dietary carbohydrate quantity and/or quality during pregnancy are associated with newborn body composition and cardiac autonomic function. Maternal diet during pregnancy was assessed in 142 mother-infant pairs using a validated food frequency questionnaire. Infant adiposity and body composition were assessed at birth using air-displacement plethysmography. Cardiac autonomic function was assessed as heart rate variability. The quantity of carbohydrates consumed during pregnancy, as a percentage of total energy intake, was not associated with meaningful differences in offspring birth weight, adiposity or heart rate variability (p > 0.05. There was some evidence that maternal carbohydrate quality, specifically higher fibre and lower glycemic index, is associated with higher heart rate variability in the newborn offspring (p = 0.06. This suggests that poor maternal carbohydrate quality may be an important population-level inter-generational risk factor for later cardiac and hemodynamic risk of their offspring.

Oral Contraceptives Attenuate Cardiac Autonomic Responses to Musical Auditory Stimulation: Pilot Study.

Science.gov (United States)

Milan, Réveni Carmem; Plassa, Bruna Oliveira; Guida, Heraldo Lorena; de Abreu, Luiz Carlos; Gomes, Rayana L; Garner, David M; Valenti, Vitor E

2015-01-01

The literature presents contradictory results regarding the effects of contraceptives on cardiac autonomic regulation. The research team aimed to evaluate the effects of musical auditory stimulation on cardiac autonomic regulation in women who use oral contraceptives. The research team designed a transversal observational pilot study. The setting was the Centro de Estudos do Sistema Nervoso Autônomo (CESNA) in the Departamento de Fonoaudiologia at the Universidade Estadual Paulista (UNESP) in Marília, SP, Brazil. Participants were 22 healthy nonathletic and nonsedentary females, all nonsmokers and aged between 18 and 27 y. Participants were divided into 2 groups: (1) 12 women who were not taking oral contraceptives, the control group; and (2) 10 women who were taking oral contraceptives, the oral contraceptive group. In the first stage, a rest control, the women sat with their earphones turned off for 20 min. After that period, the participants were exposed to 20 min of classical baroque music (ie, "Canon in D Major," Johann Pachelbel), at 63-84 dB. Measurements of the equivalent sound levels were conducted in a soundproof room, and the intervals between consecutive heartbeats (R-R intervals) were recorded, with a sampling rate of 1000 Hz. For calculation of the linear indices, the research team used software to perform an analysis of heart rate variability (HRV). Linear indices of HRV were analyzed in the time domain: (1) the standard deviation of normal-to-normal R-R intervals (SDNN), (2) the root-mean square of differences between adjacent normal R-R intervals in a time interval (RMSSD), and (3) the percentage of adjacent R-R intervals with a difference of duration greater than 50 ms (pNN50). The study also analyzed the frequency domain-low frequency (LF), high frequency (HF), and LF/HF ratio. For the control group, the musical auditory stimulation reduced (1) the SDNN from 52.2 ± 10 ms to 48.4 ± 16 ms (P = .0034); (2) the RMSSD from 45.8 ± 22 ms to 41.2 �

Circadian profile of cardiac autonomic nervous modulation in healthy subjects

DEFF Research Database (Denmark)

Bonnemeier, Hendrik; Richardt, Gert; Potratz, Jürgen

2003-01-01

UNLABELLED: Circadian Profile of Heart Rate Variability. INTRODUCTION: Although heart rate variability (HRV) has been established as a tool to study cardiac autonomic activity, almost no data are available on the circadian patterns of HRV in healthy subjects aged 20 to 70 years. METHODS AND RESULTS...... higher in men. Younger men also exhibited significantly higher values...... parasympathetic activity. The significant gender-related difference of HRV decreases with aging. These findings emphasize the need to determine age-, gender-, and nycthemeral-dependent normal ranges for HRV assessment....

Method to measure autonomic control of cardiac function using time interval parameters from impedance cardiography

International Nuclear Information System (INIS)

Meijer, Jan H; Boesveldt, Sanne; Elbertse, Eskeline; Berendse, H W

2008-01-01

The time difference between the electrocardiogram and impedance cardiogram can be considered as a measure for the time delay between the electrical and mechanical activities of the heart. This time interval, characterized by the pre-ejection period (PEP), is related to the sympathetic autonomous nervous control of cardiac activity. PEP, however, is difficult to measure in practice. Therefore, a novel parameter, the initial systolic time interval (ISTI), is introduced to provide a more practical measure. The use of ISTI instead of PEP was evaluated in three groups: young healthy subjects, patients with Parkinson's disease, and a group of elderly, healthy subjects of comparable age. PEP and ISTI were studied under two conditions: at rest and after an exercise stimulus. Under both conditions, PEP and ISTI behaved largely similarly in the three groups and were significantly correlated. It is concluded that ISTI can be used as a substitute for PEP and, therefore, to evaluate autonomic neuropathy both in clinical and extramural settings. Measurement of ISTI can also be used to non-invasively monitor the electromechanical cardiac time interval, and the associated autonomic activity, under physiological circumstances

Impact of aging on cardiac function in a female rat model of menopause: role of autonomic control, inflammation, and oxidative stress

Science.gov (United States)

Machi, Jacqueline Freire; Dias, Danielle da Silva; Freitas, Sarah Cristina; de Moraes, Oscar Albuquerque; da Silva, Maikon Barbosa; Cruz, Paula Lázara; Mostarda, Cristiano; Salemi, Vera M C; Morris, Mariana; De Angelis, Kátia; Irigoyen, Maria-Cláudia

2016-01-01

Objective The aim of this study was to evaluate the effects of aging on metabolic, cardiovascular, autonomic, inflammatory, and oxidative stress parameters after ovarian hormone deprivation (OVX). Methods Female Wistar rats (3 or 22 months old) were divided into: young controls, young ovariectomized, old controls, and old ovariectomized (bilateral ovaries removal). After a 9-week follow-up, physical capacity, metabolic parameters, and morphometric and cardiac functions were assessed. Subsequently, arterial pressure was recorded and cardiac autonomic control was evaluated. Oxidative stress was measured on the cardiac tissue, while inflammatory profile was assessed in the plasma. Results Aging or OVX caused an increase in body and fat weight and triglyceride concentration and a decrease in both insulin sensitivity and aerobic exercise capacity. Left ventricular diastolic dysfunction and increased cardiac overload (myocardial performance index) were reported in old groups when compared with young groups. Aging and OVX led to an increased sympathetic tonus, and vagal tonus was lower only for the old groups. Tumor necrosis factor-α and interleukin-6 were increased in old groups when compared with young groups. Glutathione redox balance (GSH/GSSG) was reduced in young ovariectomized, old controls, and old ovariectomized groups when compared with young controls, indicating an increased oxidative stress. A negative correlation was found between GSH/GSSG and tumor necrosis factor-α (r=−0.6, P<0.003). Correlations were found between interleukin-6 with adipose tissue (r=0.5, P<0.009) and vagal tonus (r=−0.7, P<0.0002); and among myocardial performance index with interleukin-6 (r=0.65, P<0.0002), sympathetic tonus (r=0.55, P<0.006), and physical capacity (r=−0.55, P<0.003). The findings in this trial showed that ovariectomy aggravated the impairment of cardiac and functional effects of aging in female rats, probably associated with exacerbated autonomic dysfunction

The effect of sleep apnea severity on cardiac autonomic activity during night time in obstructive sleep apnea patients

Directory of Open Access Journals (Sweden)

Gulay Ozkececi

Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Impaired autonomic cardiac function is an important consequence of obstructive sleep apnea (OSA. This impairment is mainly due to intermittent hypoxia episodes following apneas. However, the impact of apnea severity on autonomic cardiac function remains unclear. The aim of this study was to evaluate the relationship between the severity of sleep apnea and heart rate turbulence (HRT and heart rate variability (HRV in OSA. DESIGN AND SETTING: Observational cross-sectional study conducted in the Departments of Cardiology and Pulmonary Diseases, Afyon Kocatepe University, Turkey. METHODS: 106 patients with OSA and 27 healthy volunteers were enrolled. Based on apnea hypopnea index (AHI values, obstructive sleep apnea severity was classified as follows: mild OSA (AHI ≥ 5 and 30. HRV and HRT parameters were assessed via 24-hour digital Holter electrocardiogram recordings for all subjects. RESULTS: HRV and HRT results were significantly lower among OSA patients than among control subjects (P < 0.05. However, there were no significant differences in HRT and HRV between the three patient subgroups. Correlations did emerge between AHI and the NN-interval parameter RMSSD and between oxygen desaturation and turbulence slope (respectively: r = -0.22, P = 0.037; and r = -0.28, P = 0.025. CONCLUSION: HRT and HRV results deteriorate in OSA. Correlations between apnea severity and these parameters seem to be present.

Inhibition of N-type Ca2+ channels ameliorates an imbalance in cardiac autonomic nerve activity and prevents lethal arrhythmias in mice with heart failure.

Science.gov (United States)

Yamada, Yuko; Kinoshita, Hideyuki; Kuwahara, Koichiro; Nakagawa, Yasuaki; Kuwabara, Yoshihiro; Minami, Takeya; Yamada, Chinatsu; Shibata, Junko; Nakao, Kazuhiro; Cho, Kosai; Arai, Yuji; Yasuno, Shinji; Nishikimi, Toshio; Ueshima, Kenji; Kamakura, Shiro; Nishida, Motohiro; Kiyonaka, Shigeki; Mori, Yasuo; Kimura, Takeshi; Kangawa, Kenji; Nakao, Kazuwa

2014-10-01

Dysregulation of autonomic nervous system activity can trigger ventricular arrhythmias and sudden death in patients with heart failure. N-type Ca(2+) channels (NCCs) play an important role in sympathetic nervous system activation by regulating the calcium entry that triggers release of neurotransmitters from peripheral sympathetic nerve terminals. We have investigated the ability of NCC blockade to prevent lethal arrhythmias associated with heart failure. We compared the effects of cilnidipine, a dual N- and L-type Ca(2+) channel blocker, with those of nitrendipine, a selective L-type Ca(2+) channel blocker, in transgenic mice expressing a cardiac-specific, dominant-negative form of neuron-restrictive silencer factor (dnNRSF-Tg). In this mouse model of dilated cardiomyopathy leading to sudden arrhythmic death, cardiac structure and function did not significantly differ among the control, cilnidipine, and nitrendipine groups. However, cilnidipine dramatically reduced arrhythmias in dnNRSF-Tg mice, significantly improving their survival rate and correcting the imbalance between cardiac sympathetic and parasympathetic nervous system activity. A β-blocker, bisoprolol, showed similar effects in these mice. Genetic titration of NCCs, achieved by crossing dnNRSF-Tg mice with mice lacking CACNA1B, which encodes the α1 subunit of NCCs, improved the survival rate. With restoration of cardiac autonomic balance, dnNRSF-Tg;CACNA1B(+/-) mice showed fewer malignant arrhythmias than dnNRSF-Tg;CACNA1B(+/+) mice. Both pharmacological blockade of NCCs and their genetic titration improved cardiac autonomic balance and prevented lethal arrhythmias in a mouse model of dilated cardiomyopathy and sudden arrhythmic death. Our findings suggest that NCC blockade is a potentially useful approach to preventing sudden death in patients with heart failure. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Modulation of cardiac autonomic tone in non-hypotensive hypovolemia during blood donation.

Science.gov (United States)

Yadav, Kavita; Singh, Akanksha; Jaryal, Ashok Kumar; Coshic, Poonam; Chatterjee, Kabita; Deepak, K K

2017-08-01

Non-hypotensive hypovolemia, observed during mild haemorrhage or blood donation leads to reflex readjustment of the cardiac autonomic tone. In the present study, the cardiac autonomic tone was quantified using heart rate and blood pressure variability during and after non-hypotensive hypovolemia of blood donation. 86 voluntary healthy male blood donors were recruited for the study (age 35 ± 9 years; weight 78 ± 12 kg; height 174 ± 6 cms). Continuous lead II ECG and beat-to-beat blood pressure was recorded before, during and after blood donation followed by offline time and frequency domain analysis of HRV and BPV. The overall heart rate variability (SDNN and total power) did not change during or after blood donation. However, there was a decrease in indices that represent the parasympathetic component (pNN50 %, SDSD and HF) while an increase was observed in sympathetic component (LF) along with an increase in sympathovagal balance (LF:HF ratio) during blood donation. These changes were sustained for the period immediately following blood donation. No fall of blood pressure was observed during the period of study. The blood pressure variability showed an increase in the SDNN, CoV and RMSSD time domain measures in the post donation period. These results suggest that mild hypovolemia produced by blood donation is non-hypotensive but is associated with significant changes in the autonomic tone. The increased blood pressure variability and heart rate changes that are seen only in the later part of donation period could be because of the progressive hypovolemia associated parasympathetic withdrawal and sympathetic activation that manifest during the course of blood donation.

Prevalence and pattern of cardiac autonomic dysfunction in newly detected type 2 diabetes mellitus.

Science.gov (United States)

Jyotsna, Viveka P; Sahoo, Abhay; Sreenivas, V; Deepak, K K

2009-01-01

Cardiac autonomic functions were assessed in 145 consecutive recently detected type 2 diabetics. Ninety-nine healthy persons served as controls. Criteria for normalcy were, heart rate variation during deep breathing >or=15 beats/min, deep breathing expiratory to inspiratory R-R ratio >or=1.21, Valsalva ratio >or=1.21, sustained handgrip test >or=16 mm of mercury, cold pressor test >or=10, BP response to standing or=1.04. An abnormal test was defined as the above parameters being or=30 mm of mercury and Cardiac autonomic function was normal in 7.8% patients and 32.5% healthy controls.

Regular physical exercise improves cardiac autonomic and muscle vasodilatory responses to isometric exercise in healthy elderly

Science.gov (United States)

Sarmento, Adriana de Oliveira; Santos, Amilton da Cruz; Trombetta, Ivani Credidio; Dantas, Marciano Moacir; Oliveira Marques, Ana Cristina; do Nascimento, Leone Severino; Barbosa, Bruno Teixeira; Dos Santos, Marcelo Rodrigues; Andrade, Maria do Amparo; Jaguaribe-Lima, Anna Myrna; Brasileiro-Santos, Maria do Socorro

2017-01-01

The objective of this study was to evaluate cardiac autonomic control and muscle vasodilation response during isometric exercise in sedentary and physically active older adults. Twenty healthy participants, 10 sedentary and 10 physically active older adults, were evaluated and paired by gender, age, and body mass index. Sympathetic and parasympathetic cardiac activity (spectral and symbolic heart rate analysis) and muscle blood flow (venous occlusion plethysmography) were measured for 10 minutes at rest (baseline) and during 3 minutes of isometric handgrip exercise at 30% of the maximum voluntary contraction (sympathetic excitatory maneuver). Variables were analyzed at baseline and during 3 minutes of isometric exercise. Cardiac autonomic parameters were analyzed by Wilcoxon and Mann–Whitney tests. Muscle vasodilatory response was analyzed by repeated-measures analysis of variance followed by Tukey’s post hoc test. Sedentary older adults had higher cardiac sympathetic activity compared to physically active older adult subjects at baseline (63.13±3.31 vs 50.45±3.55 nu, P=0.02). The variance (heart rate variability index) was increased in active older adults (1,438.64±448.90 vs 1,402.92±385.14 ms, P=0.02), and cardiac sympathetic activity (symbolic analysis) was increased in sedentary older adults (5,660.91±1,626.72 vs 4,381.35±1,852.87, P=0.03) during isometric handgrip exercise. Sedentary older adults showed higher cardiac sympathetic activity (spectral analysis) (71.29±4.40 vs 58.30±3.50 nu, P=0.03) and lower parasympathetic modulation (28.79±4.37 vs 41.77±3.47 nu, P=0.03) compared to physically active older adult subjects during isometric handgrip exercise. Regarding muscle vasodilation response, there was an increase in the skeletal muscle blood flow in the second (4.1±0.5 vs 3.7±0.4 mL/min per 100 mL, P=0.01) and third minute (4.4±0.4 vs 3.9±0.3 mL/min per 100 mL, P=0.03) of handgrip exercise in active older adults. The results indicate that

Short-term supervised inpatient physiotherapy exercise protocol improves cardiac autonomic function after coronary artery bypass graft surgery--a randomised controlled trial.

Science.gov (United States)

Mendes, Renata Gonçalves; Simões, Rodrigo Polaquini; De Souza Melo Costa, Fernando; Pantoni, Camila Bianca Falasco; Di Thommazo, Luciana; Luzzi, Sérgio; Catai, Aparecida Maria; Arena, Ross; Borghi-Silva, Audrey

2010-01-01

Coronary artery bypass grafting (CABG) is accompanied by severe impairment of cardiac autonomous regulation (CAR). This study aimed to determine whether a short-term physiotherapy exercise protocol post-CABG, during inpatient cardiac rehabilitation (CR), might improve CAR. Seventy-four patients eligible for CABG were recruited and randomised into physiotherapy exercise group (EG) or physiotherapy usual care group (UCG). EG patients underwent a short-term supervised inpatient physiotherapy exercise protocol consisting of an early mobilisation with progressive exercises plus usual care (respiratory exercises). UCG only received respiratory exercises. Forty-seven patients (24 EG and 23 UGC) completed the study. Outcome measures of CAR included linear and non-linear measures of heart rate variability (HRV) assessed before discharge. By hospital discharge, EG presented significantly higher parasympathetic HRV values [rMSSD, high frequency (HF), SD1)], global power (STD RR, SD2), non-linear HRV indexes [detrended fluctuation analysis (DFA)alpha1, DFAalpha2, approximate entropy (ApEn)] and mean RR compared to UCG (pexercise protocol during inpatient CR improves CAR at the time of discharge. Thus, exercise-based inpatient CR might be an effective non-pharmacological tool to improve autonomic cardiac tone in patient's post-CABG.

Prenatal stress and balance of the child's cardiac autonomic nervous system at age 5-6 years.

Directory of Open Access Journals (Sweden)

Aimée E van Dijk

Full Text Available OBJECTIVE: Autonomic nervous system (ANS misbalance is a potential causal factor in the development of cardiovascular disease. The ANS may be programmed during pregnancy due to various maternal factors. Our aim is to study maternal prenatal psychosocial stress as a potential disruptor of cardiac ANS balance in the child. METHODS: Mothers from a prospective birth cohort (ABCD study filled out a questionnaire at gestational week 16 [IQR 12-20], that included validated instruments for state anxiety, depressive symptoms, pregnancy-related anxiety, parenting daily hassles and job strain. A cumulative stress score was also calculated (based on 80(th percentiles. Indicators of cardiac ANS in the offspring at age 5-6 years are: pre-ejection period (PEP, heart rate (HR, respiratory sinus arrhythmia (RSA and cardiac autonomic balance (CAB, measured with electrocardiography and impedance cardiography in resting supine and sitting positions. RESULTS: 2,624 mother-child pairs, only single births, were available for analysis. The stress scales were not significantly associated with HR, PEP, RSA and CAB (p≥0.17. Accumulation of maternal stress was also not associated with HR, PEP, RSA and CAB (p≥0.07. CONCLUSION: Results did not support the hypothesis that prenatal maternal psychosocial stress deregulates cardiac ANS balance in the offspring, at least in rest, and at the age of five-six years.

Combined moderate and high intensity exercise with dietary restriction improves cardiac autonomic function associated with a reduction in central and systemic arterial stiffness in obese adults: a clinical trial

Directory of Open Access Journals (Sweden)

Min Hu

2017-10-01

Full Text Available Objective The present study aimed to assess the effects of exercise with dietary restriction on cardiac autonomic activity, arterial stiffness, and cardiovascular biomarkers in obese individuals. Methods Seventeen obese adults completed an 8-week exercise and dietary program. Anthropometry, body composition, and multiple biochemical markers were measured. We used carotid-femoral pulse wave velocity (cfPWV, brachial-ankle pulse wave velocity (baPWV, central blood pressure, and augmentation index (AIx to assess arterial stiffness. To determine cardiac autonomic activity, heart rate variability (HRV was analyzed by standard deviation of normal-to-normal intervals (SDNN, square root of the mean squared differences of successive normal-to-normal intervals (RMSSD, total power (TF, low-frequency power in normalized units (LFnu, high-frequency power in normalized units (HFnu, and low-frequency power/high-frequency power (LF/HF. Results Following the exercise and diet intervention, obese subjects had significant reductions in body weight, body mass index, body fat percentage, brachial systolic blood pressure, and resting heart rate, and they had shown improvements in blood chemistry markers such as lipid profiles, insulin, and high-sensitivity C-reactive protein. There was a significant reduction in both cfPWV and baPWV following the intervention when compared to baseline levels. Moreover, the AIx and aortic systolic blood pressure were significantly reduced after the intervention. The diet and exercise intervention significantly increased cardiac autonomic modulation (determined by improved SDNN, RMSSD, TP LF, HF, and LF/HF, which was partly due to changes in heart rate, insulin resistance, and the inflammatory pattern. Furthermore, we observed a correlation between enhanced cardiac autonomic modulation (LF/HF and decreased arterial stiffness, as measured by central cfPWV and systemic baPWV. Discussion An 8-week combined intervention of diet and

Cardiac autonomic function and hot flashes among perimenopausal and postmenopausal women.

Science.gov (United States)

Gibson, Carolyn J; Mendes, Wendy Berry; Schembri, Michael; Grady, Deborah; Huang, Alison J

2017-07-01

Abnormalities in autonomic function are posited to play a pathophysiologic role in menopausal hot flashes. We examined relationships between resting cardiac autonomic activity and hot flashes in perimenopausal and postmenopausal women. Autonomic function was assessed at baseline and 12 weeks among perimenopausal and postmenopausal women (n = 121, mean age 53 years) in a randomized trial of slow-paced respiration for hot flashes. Pre-ejection period (PEP), a marker of sympathetic activation, was measured with impedance cardiography. Respiratory sinus arrhythmia (RSA), a marker of parasympathetic activation, was measured with electrocardiography. Participants self-reported hot flash frequency and severity in 7-day symptom diaries. Analysis of covariance models were used to relate autonomic function and hot flash frequency and severity at baseline, and to relate changes in autonomic function to changes in hot flash frequency and severity over 12 weeks, adjusting for age, body mass index, and intervention assignment. PEP was not associated with hot flash frequency or severity at baseline or over 12 weeks (P > 0.05 for all). In contrast, there was a trend toward greater frequency of moderate-to-severe hot flashes with higher RSA at baseline (β = 0.43, P = 0.06), and a positive association between change in RSA and change in frequency of moderate-to-severe hot flashes over 12 weeks (β = 0.63, P = 0.04). Among perimenopausal and postmenopausal women with hot flashes, variations in hot flash frequency and severity were not explained by variations in resting sympathetic activation. Greater parasympathetic activation was associated with more frequent moderate-to-severe hot flashes, which may reflect increased sensitivity to perceiving hot flashes.

Effects of inspiratory muscle exercise in the pulmonary function, autonomic modulation, and hemodynamic variables in older women with metabolic syndrome

Science.gov (United States)

Feriani, Daniele Jardim; Coelho, Hélio José; Scapini, Kátia Bilhar; de Moraes, Oscar Albuquerque; Mostarda, Cristiano; Ruberti, Olivia Moraes; Uchida, Marco Carlos; Caperuto, Érico Chagas; Irigoyen, Maria Cláudia; Rodrigues, Bruno

2017-01-01

The aim of the present study was to investigate the effects of inspiratory muscle exercise (IME) on metabolic and hemodynamic parameters, cardiac autonomic modulation and respiratory function of older women with metabolic syndrome (MS). For this, sixteen older women with MS and 12 aged-matched controls participated of the present study. Two days before and 2 days after the main experiment, fasting blood samples (i.e., total cholesterol, triglycerides and blood glucose), cardiac autonomic modulation (i.e., heart rate variability), and respiratory muscle function were obtained and evaluated. The sessions of physical exercise was based on a IME, which was performed during 7 days. Each session of IME was performed during 20 min, at 30% of maximal static inspiratory pressure. In the results, MS group presented higher levels of triglycerides, blood glucose, and systolic blood pressure when compared to control group. IME was not able to change these variables. However, although MS group showed impaired respiratory muscle strength and function, as well as cardiac autonomic modulation, IME was able to improve these parameters. Thus, the data showed that seven days of IME are capable to improve respiratory function and cardiac autonomic modulation of older women with MS. These results indicate that IME can be a profitable therapy to counteracting the clinical markers of MS, once repeated sessions of acute IME can cause chronical alterations on respiratory function and cardiac autonomic modulation. PMID:28503537

Bidirectional Prospective Associations Between Cardiac Autonomic Activity and Inflammatory Markers.

Science.gov (United States)

Hu, Mandy Xian; Lamers, Femke; Neijts, Melanie; Willemsen, Gonneke; de Geus, Eco J C; Penninx, Brenda W J H

2018-06-01

Autonomic nervous system (ANS) imbalance has been cross-sectionally associated with inflammatory processes. Longitudinal studies are needed to shed light on the nature of this relationship. We examined cross-sectional and bidirectional prospective associations between cardiac autonomic measures and inflammatory markers. Analyses were conducted with baseline (n = 2823), 2-year (n = 2099), and 6-year (n = 1774) data from the Netherlands Study of Depression and Anxiety. To compare the pattern of results, prospective analyses with ANS (during sleep, leisure time, and work) and inflammation were conducted in two data sets from the Netherlands Twin Register measured for 4.9 years (n = 356) and 5.4 years (n = 472). Autonomic nervous system measures were heart rate (HR) and respiratory sinus arrhythmia (RSA). Inflammatory markers were C-reactive protein (CRP) and interleukin (IL)-6. The Netherlands Study of Depression and Anxiety results showed that higher HR and lower RSA were cross-sectionally significantly associated with higher inflammatory levels. Higher HR predicted higher levels of CRP (B = .065, p < .001) and IL-6 (B = .036, p = .014) at follow-up. Higher CRP levels predicted lower RSA (B = -.024, p = .048) at follow-up. The Netherlands Twin Register results confirmed that higher HR was associated with higher CRP and IL-6 levels 4.9 years later. Higher IL-6 levels predicted higher HR and lower RSA at follow-up. Autonomic imbalance is associated with higher levels of inflammation. Independent data from two studies converge in evidence that higher HR predicts subsequent higher levels of CRP and IL-6. Inflammatory markers may also predict future ANS activity, but evidence for this was less consistent.

An Autonomic Link Between Inhaled Diesel Exhaust and Impaired Cardiac Performance: Insight From Treadmill and Doubutamine Challenges in Heart Failure-Prone Rats

Science.gov (United States)

Background: Short-term exposure to vehicular emissions is associated with adverse cardiac events. Diesel exhaust (DE) is an ubiquitous air pollutant believed to provoke cardiac events partly through imbalance of the sympathetic and parasympathetic branches of the autonomic nervo...

Cardiac effects produced by long-term stimulation of thoracic autonomic ganglia or nerves: implications for interneuronal interactions within the thoracic autonomic nervous system.

Science.gov (United States)

Butler, C; Watson-Wright, W M; Wilkinson, M; Johnstone, D E; Armour, J A

1988-03-01

Electrical stimulation of an acutely decentralized stellate or middle cervical ganglion or cardiopulmonary nerve augments cardiac chronotropism or inotropism; as the stimulation continues there is a gradual reduction of this augmentation following the peak response, i.e., an inhibition of augmentation. The amount of this inhibition was found to be dependent upon the region of the heart investigated and the neural structure stimulated. The cardiac parameters which were augmented the most displayed the greatest inhibition. Maximum augmentation or inhibition occurred, in most instances, when 5-20 Hz stimuli were used. Inhibition of augmentation was overcome when the stimulation frequency was subsequently increased or following the administration of nicotine or tyramine, indicating that the inhibition was not primarily due to the lack of availability of noradrenaline in the nerve terminals of the efferent postganglionic sympathetic neurons. Furthermore, as infusions of isoproterenol or noradrenaline during the period of inhibition could still augment cardiac responses, whereas during the early peak responses they did not, the inhibition of augmentation does not appear to be due primarily to down regulation of cardiac myocyte beta-adrenergic receptors. The inhibition was modified by hexamethonium but not by phentolamine or atropine. Inhibition occurred when all ipsilateral cardiopulmonary nerves connected with acutely decentralized middle cervical and stellate ganglia were stimulated, whereas significant inhibition did not occur when these nerves were stimulated after they had been disconnected from the ipsilateral decentralized ganglia. Taken together these data indicate that the inhibition of cardiac augmentation which occurs during relatively long-term stimulation of intrathoracic sympathetic neural elements is due in large part to nicotinic cholinergic synaptic mechanisms that lie primarily in the major thoracic autonomic ganglia. They also indicate that long

Impact of aging on cardiac function in a female rat model of menopause: role of autonomic control, inflammation, and oxidative stress

Directory of Open Access Journals (Sweden)

Machi JF

2016-03-01

Full Text Available Jacqueline Freire Machi,1,2 Danielle da Silva Dias,3 Sarah Cristina Freitas,3 Oscar Albuquerque de Moraes,1 Maikon Barbosa da Silva,1 Paula Lázara Cruz,1 Cristiano Mostarda,4 Vera M C Salemi,1 Mariana Morris,2 Kátia De Angelis,3 Maria-Cláudia Irigoyen1 1Hypertension Unit, Heart Institute (InCor, School of Medicine, University of Sao Paulo, São Paulo, Brazil; 2Institute of Neuro-Immune Medicine, Nova Southeastern University, Fort Lauderdale, FL, USA; 3Laboratory of Translational Physiology, Universidade Nove de Julho (UNINOVE, São Paulo, 4Health Adult and Child, Federal University of Maranhao (UFMA, São Luiz, Maranhão, Brazil Objective: The aim of this study was to evaluate the effects of aging on metabolic, cardiovascular, autonomic, inflammatory, and oxidative stress parameters after ovarian hormone deprivation (OVX. Methods: Female Wistar rats (3 or 22 months old were divided into: young controls, young ovariectomized, old controls, and old ovariectomized (bilateral ovaries removal. After a 9-week follow-up, physical capacity, metabolic parameters, and morphometric and cardiac functions were assessed. Subsequently, arterial pressure was recorded and cardiac autonomic control was evaluated. Oxidative stress was measured on the cardiac tissue, while inflammatory profile was assessed in the plasma. Results: Aging or OVX caused an increase in body and fat weight and triglyceride concentration and a decrease in both insulin sensitivity and aerobic exercise capacity. Left ventricular diastolic dysfunction and increased cardiac overload (myocardial performance index were reported in old groups when compared with young groups. Aging and OVX led to an increased sympathetic tonus, and vagal tonus was lower only for the old groups. Tumor necrosis factor-α and interleukin-6 were increased in old groups when compared with young groups. Glutathione redox balance (GSH/GSSG was reduced in young ovariectomized, old controls, and old ovariectomized

Autonomic, locomotor and cardiac abnormalities in a mouse model of muscular dystrophy: targeting the renin-angiotensin system.

Science.gov (United States)

Sabharwal, Rasna; Chapleau, Mark W

2014-04-01

New Findings What is the topic of this review? This symposium report summarizes autonomic, cardiac and skeletal muscle abnormalities in sarcoglycan-δ-deficient mice (Sgcd-/-), a mouse model of limb girdle muscular dystrophy, with emphasis on the roles of autonomic dysregulation and activation of the renin-angiotensin system at a young age. What advances does it highlight? The contributions of the autonomic nervous system and the renin-angiotensin system to the pathogenesis of muscular dystrophy are highlighted. Results demonstrate that autonomic dysregulation precedes and predicts later development of cardiac dysfunction in Sgcd-/- mice and that treatment of young Sgcd-/- mice with the angiotensin type 1 receptor antagonist losartan or with angiotensin-(1-7) abrogates the autonomic dysregulation, attenuates skeletal muscle pathology and increases spontaneous locomotor activity. Muscular dystrophies are a heterogeneous group of genetic muscle diseases characterized by muscle weakness and atrophy. Mutations in sarcoglycans and other subunits of the dystrophin-glycoprotein complex cause muscular dystrophy and dilated cardiomyopathy in animals and humans. Aberrant autonomic signalling is recognized in a variety of neuromuscular disorders. We hypothesized that activation of the renin-angiotensin system contributes to skeletal muscle and autonomic dysfunction in mice deficient in the sarcoglycan-δ (Sgcd) gene at a young age and that this early autonomic dysfunction contributes to the later development of left ventricular (LV) dysfunction and increased mortality. We demonstrated that young Sgcd-/- mice exhibit histopathological features of skeletal muscle dystrophy, decreased locomotor activity and severe autonomic dysregulation, but normal LV function. Autonomic regulation continued to deteriorate in Sgcd-/- mice with age and was accompanied by LV dysfunction and dilated cardiomyopathy at older ages. Autonomic dysregulation at a young age predicted later development of

The Effect of Heart Rate on the Heart Rate Variability Response to Autonomic Interventions

Directory of Open Access Journals (Sweden)

George E Billman

2013-08-01

Full Text Available Heart rate variability (HRV, the beat-to-beat variation in either heart rate (HR or heart period (R-R interval, has become a popular clinical and investigational tool to quantify cardiac autonomic regulation. However, it is not widely appreciated that, due to the inverse curvilinear relationship between HR and R-R interval, HR per se can profoundly influence HRV. It is, therefore, critical to correct HRV for the prevailing HR particularly, as HR changes in response to autonomic neural activation or inhibition. The present study evaluated the effects of HR on the HRV response to autonomic interventions that either increased (submaximal exercise, n = 25 or baroreceptor reflex activation, n = 20 or reduced (pharmacological blockade: β-adrenergic receptor, muscarinic receptor antagonists alone and in combination, n = 25, or bilateral cervical vagotomy, n = 9 autonomic neural activity in a canine model. Both total (RR interval standard deviation, RRSD and the high frequency variability (HF, 0.2 to 1.04 Hz were determined before and in response to an autonomic intervention. All interventions that reduced or abolished cardiac parasympathetic regulation provoked large reductions in HRV even after HR correction [division by mean RRsec or (mean RRsec2 for RRSD and HF, respectively] while interventions that reduced HR yielded mixed results. β-adrenergic receptor blockade reduced HRV (RRSD but not HF while both RRSD and HF increased in response to increases in arterial blood (baroreceptor reflex activation even after HR correction. These data suggest that the physiological basis for HRV is revealed after correction for prevailing HR and, further, that cardiac parasympathetic activity is responsible for a major portion of the HRV in the dog.

Sudarshan Kriya Yoga improves cardiac autonomic control in patients with anxiety-depression disorders.

Science.gov (United States)

Toschi-Dias, Edgar; Tobaldini, Eleonora; Solbiati, Monica; Costantino, Giorgio; Sanlorenzo, Roberto; Doria, Stefania; Irtelli, Floriana; Mencacci, Claudio; Montano, Nicola

2017-05-01

Several studies have demonstrated that adjuvant therapies as exercise and breathing training are effective in improving cardiac autonomic control (CAC) in patients with affective spectrum disorders. However, the effects of Sudarshan Kriya Yoga (SKY) on autonomic function in this population is unknown. Our objective was to test the hypothesis that SKY training improves CAC and cardiorespiratory coupling in patients with anxiety and/or depression disorders. Forty-six patients with a diagnosis of anxiety and/or depression disorders (DSM-IV) were consecutively enrolled and divided in two groups: 1) conventional therapy (Control) and 2) conventional therapy associated with SKY (Treatment) for 15 days. Anxiety and depression levels were determined using quantitative questionnaires. For the assessment of CAC and cardiorespiratory coupling, cardiorespiratory traces were analyzed using monovariate and bivariate autoregressive spectral analysis, respectively. After 15-days, we observed a reduction of anxiety and depression levels only in Treatment group. Moreover, sympathetic modulation and CAC were significantly lower while parasympathetic modulation and cardiorespiratory coupling were significantly higher in the Treatment compared to Control group. Intensive breathing training using SKY approach improves anxiety and/or depressive disorders as well as CAC and cardiorespiratory coupling. These finding suggest that the SKY training may be a useful non-pharmacological intervention to improve symptoms and reduce cardiovascular risk in patients with anxiety/depression disorders. Copyright © 2017 Elsevier B.V. All rights reserved.

Influence of hydrotherapy on clinical and cardiac autonomic function in migraine patients.

Science.gov (United States)

Sujan, M U; Rao, M Raghavendra; Kisan, Ravikiran; Abhishekh, Hulegar A; Nalini, Atchayaram; Raju, Trichur R; Sathyaprabha, T N

2016-01-01

Migraine is associated with autonomic symptoms. The growing body of literature suggests that the dysfunctional autonomic nervous system might play a pivotal role in the pathogenesis of migraine. Thermal therapies have been hypothesized to modulate these changes and alleviate pain. However, data regarding the efficacy of hydrotherapy in migraine remain scant. We evaluated the effect of add on hydrotherapy procedure (a hot arm and foot bath with ice massage to head) in migraine patients. Forty chronic migraine patients fulfilling the International Classification of Headache Disorders II criteria were recruited from the neurology outpatient clinic. Patients were randomized to receive either hydrotherapy plus conventional pharmacological care (n = 20) or conventional medication only (n = 20). Hydrotherapy group received treatment with hot arm and foot bath (103°F to 110°F) and ice massage to head daily for 20 min for 45 days. Patients were assessed using headache impact test (HIT), visual analog scale for pain and cardiac autonomic function by heart rate variability (HRV) before and after intervention period. There was a significant decrease in HIT score, frequency, and intensity of headaches following treatment in both the groups. However, it was more evident in add on hydrotherapy group compared to pharmacological treatment alone group. There was also significant improvement in the HRV parameters. In particular, there was a significant decrease in heart rate (P = 0.017), increase in high frequency (HF) (P = 0.014) and decrease in low frequency/HF ratio (P = 0.004) in add on hydrotherapy group. Our study shows that add on hydrotherapy enhanced the vagal tone in addition to reducing the frequency and intensity of headaches in migraine patients.

Cardiac autonomic regulation in response to a mixed meal is impaired in obese children and adolescents: the role played by insulin resistance.

Science.gov (United States)

Cozzolino, Domenico; Esposito, Katherine; Palmiero, Giuseppe; De Bellis, Annamaria; Furlan, Raffaello; Perrotta, Silverio; Perrone, Laura; Torella, Daniele; Miraglia del Giudice, Emanuele

2014-09-01

Obesity in children/adolescents has been associated with subtle cardiac abnormalities, including myocardial dysfunction and cardiac autonomic dysregulation at rest, both likely responsible for a higher mortality in adulthood. Food intake induces remarkable adjustments of cardiovascular autonomic activity in healthy subjects. The objective of the study was to evaluate in obese children/adolescents meal-induced cardiac autonomic response and the role played by insulin resistance. Sixty-eight obese and 30 matched normal-weight children/adolescents underwent blood sampling and cardiovascular autonomic analysis while recumbent and 20 minutes after a mixed meal ingestion. Spectrum analysis of the R-R interval and systolic blood pressure (SBP) variability provided the indices of sympathetic [low frequency (LFRR)] and vagal [high frequency (HFRR)] modulation of the sinoatrial node and the low frequency component of SBP. The homeostasis model assessment of insulin resistance served to separate insulin resistant (n = 35) from non insulin resistant (n = 33) obese children/adolescents. At baseline, C-reactive protein, the LFRR to HFRR ratio, SBP, and low frequency oscillatory component of SBP variability in obese children/adolescents were significantly (P meal-induced increase in the LFRR to HFRR ratio was significantly less than in controls and exaggeratedly scanty (or opposite) among insulin resistant subjects. The homeostasis model assessment of insulin resistance index strongly and inversely correlated (r = -0.871; P meal-induced changes in the LFRR to HFRR ratio among obese subjects. Autonomic modulation of the heart was impaired after eating in obese children/adolescents. This abnormality was exaggerated among insulin resistant subjects and strongly correlated with the degree of insulin resistance.

Marine n-3 Polyunsaturated Fatty Acids in Psoriatic Arthritis – Inflammation and Cardiac Autonomic and Hemodynamic Function

DEFF Research Database (Denmark)

Kristensen, Salome

This thesis is based on three studies of patients with established psoriatic arthritis (PsA) aiming at investigating the effect of marine n-3 polyunsaturated fatty acids (PUFA) on clinical symptoms and selected measures of inflammation, cardiac autonomic and hemodynamic function in these patients...... with either 3 g of marine n-3 PUFA (6 capsules of fish oil) or 3 g of olive oil daily for 24 weeks. A total of 133 patients (92%) completed the study. The difference in the outcomes between baseline and 24 weeks was analysed within and between the two supplemented groups. In Study II, the effects of n-3 PUFA...

Early Seizure Detection Based on Cardiac Autonomic Regulation Dynamics

Directory of Open Access Journals (Sweden)

Jonatas Pavei

2017-10-01

Full Text Available Epilepsy is a neurological disorder that causes changes in the autonomic nervous system. Heart rate variability (HRV reflects the regulation of cardiac activity and autonomic nervous system tone. The early detection of epileptic seizures could foster the use of new treatment approaches. This study presents a new methodology for the prediction of epileptic seizures using HRV signals. Eigendecomposition of HRV parameter covariance matrices was used to create an input for a support vector machine (SVM-based classifier. We analyzed clinical data from 12 patients (9 female; 3 male; age 34.5 ± 7.5 years, involving 34 seizures and a total of 55.2 h of interictal electrocardiogram (ECG recordings. Data from 123.6 h of ECG recordings from healthy subjects were used to test false positive rate per hour (FP/h in a completely independent data set. Our methodological approach allowed the detection of impending seizures from 5 min to just before the onset of a clinical/electrical seizure with a sensitivity of 94.1%. The FP rate was 0.49 h−1 in the recordings from patients with epilepsy and 0.19 h−1 in the recordings from healthy subjects. Our results suggest that it is feasible to use the dynamics of HRV parameters for the early detection and, potentially, the prediction of epileptic seizures.

Affect during incremental exercise: The role of inhibitory cognition, autonomic cardiac function, and cerebral oxygenation.

Directory of Open Access Journals (Sweden)

Weslley Quirino Alves da Silva

Full Text Available Pleasure is a key factor for physical activity behavior in sedentary individuals. Inhibitory cognitive control may play an important role in pleasure perception while exercising, especially at high intensities. In addition, separate work suggests that autonomic regulation and cerebral hemodynamics influence the affective and cognitive responses during exercise.We investigated the effects of exercise intensity on affect, inhibitory control, cardiac autonomic function, and prefrontal cortex (PFC oxygenation.Thirty-seven sedentary young adults performed two experimental conditions (exercise and control in separate sessions in a repeated-measures design. In the exercise condition, participants performed a maximum graded exercise test on a cycle ergometer as we continuously measured oxygen consumption, heart rate variability (HRV, and PFC oxygenation. At each of 8 intensity levels we also measured inhibitory control (Stroop test, associative and dissociative thoughts (ADT, and affective/pleasure ratings. In the control condition, participants sat motionless on a cycle ergometer without active pedaling, and we collected the same measures at the same points in time as the exercise condition. We evaluated the main effects and interactions of exercise condition and intensity level for each measure using two-way repeated measures ANOVAs. Additionally, we evaluated the relationship between affect and inhibitory control, ADT, HRV, and PFC oxygenation using Pearson's correlation coefficients.For exercise intensities below and at the ventilatory threshold (VT, participants reported feeling neutral, with preservation of inhibitory control, while intensities above the VT were associated with displeasure (p<0.001, decreased inhibitory control and HRV (p<0.001, and increased PFC oxygenation (p<0.001. At the highest exercise intensity, pleasure was correlated with the low-frequency index of HRV (r = -0.34; p<0.05 and the low-frequency/high-frequency HRV ratio (r

Effects of local cardiac denervation on cardiac innervation and ventricular arrhythmia after chronic myocardial infarction.

Directory of Open Access Journals (Sweden)

Xudong Liu

Full Text Available Modulation of the autonomic nervous system (ANS has already been demonstrated to display antiarrhythmic effects in patients and animals with MI. In this study, we investigated whether local cardiac denervation has any beneficial effects on ventricular electrical stability and cardiac function in the chronic phase of MI.Twenty-one anesthetized dogs were randomly assigned into the sham-operated, MI and MI-ablation groups, respectively. Four weeks after local cardiac denervation, LSG stimulation was used to induce VPCs and VAs. The ventricular fibrillation threshold (VFT and the incidence of inducible VPCs were measured with electrophysiological protocol. Cardiac innervation was determined with immunohistochemical staining of growth associated protein-43 (GAP43 and tyrosine hydroxylase (TH. The global cardiac and regional ventricular function was evaluated with doppler echocardiography in this study.Four weeks after operation, the incidence of inducible VPC and VF in MI-ablation group were significantly reduced compared to the MI dogs (p<0.05. Moreover, local cardiac denervation significantly improved VFT in the infarcted border zone (p<0.05. The densities of GAP43 and TH-positive nerve fibers in the infarcted border zone in the MI-ablation group were lower than those in the MI group (p<0.05. However, the local cardiac denervation did not significantly improve cardiac function in the chronic phase of MI, determined by the left ventricle diameter (LV, left atrial diameter (LA, ejection fraction (EF.Summarily, in the chronic phase of MI, local cardiac denervation reduces the ventricular electrical instability, and attenuates spatial heterogeneity of sympathetic nerve reconstruction. Our study suggests that this methodology might decrease malignant ventricular arrhythmia in chronic MI, and has a great potential for clinical application.

Effect of Head-Down Bed Rest and Artificial Gravity Countermeasure on Cardiac Autonomic and Advanced Electrocardiographic Function

Science.gov (United States)

Schlegel, T. T.; Platts, S.; Stenger, M.; Ribeiro, C.; Natapoff, A.; Howarth, M.; Evans, J.

2007-01-01

To study the effects of 21 days of head-down bed rest (HDBR), with versus without an artificial gravity (AG) countermeasure, on cardiac autonomic and advanced electrocardiographic function. Fourteen healthy men participated in the study: seven experienced 21 days of HDBR alone ("HDBR controls") and seven the same degree and duration of HDBR but with approximately 1hr daily short-arm centrifugation as an AG countermeasure ("AG-treated"). Five minute supine high-fidelity 12-lead ECGs were obtained in all subjects: 1) 4 days before HDBR; 2) on the last day of HDBR; and 3) 7 days after HDBR. Besides conventional 12-lead ECG intervals and voltages, all of the following advanced ECG parameters were studied: 1) both stochastic (time and frequency domain) and deterministic heart rate variability (HRV); 2) beat-to-beat QT interval variability (QTV); 3) T-wave morphology, including signal-averaged T-wave residua (TWR) and principal component analysis ratios; 4) other SAECG-related parameters including high frequency QRS ECG and late potentials; and 5) several advanced ECG estimates of left ventricular (LV) mass. The most important results by repeated measures ANOVA were that: 1) Heart rates, Bazett-corrected QTc intervals, TWR, LF/HF power and the alpha 1 of HRV were significantly increased in both groups (i.e., by HDBR), but with no relevant HDBR*group differences; 2) All purely "vagally-mediated" parameters of HRV (e.g., RMSSD, HF power, Poincare SD1, etc.), PR intervals, and also several parameters of LV mass (Cornell and Sokolow-Lyon voltages, spatial ventricular activation times, ventricular gradients) were all significantly decreased in both groups (i.e., by HDBR), but again with no relevant HDBR*group differences); 3) All "generalized" or "vagal plus sympathetic" parameters of stochastic HRV (i.e., SDNN, total power, LF power) were significantly more decreased in the AG-treated group than in the HDBR-only group (i.e., here there was a relevant HDBR*group difference

Influence of hydrotherapy on clinical and cardiac autonomic function in migraine patients

Directory of Open Access Journals (Sweden)

M U Sujan

2016-01-01

Full Text Available Background: Migraine is associated with autonomic symptoms. The growing body of literature suggests that the dysfunctional autonomic nervous system might play a pivotal role in the pathogenesis of migraine. Thermal therapies have been hypothesized to modulate these changes and alleviate pain. However, data regarding the efficacy of hydrotherapy in migraine remain scant. We evaluated the effect of add on hydrotherapy procedure (a hot arm and foot bath with ice massage to head in migraine patients. Methods: Forty chronic migraine patients fulfilling the International Classification of Headache Disorders II criteria were recruited from the neurology outpatient clinic. Patients were randomized to receive either hydrotherapy plus conventional pharmacological care (n = 20 or conventional medication only (n = 20. Hydrotherapy group received treatment with hot arm and foot bath (103°F to 110°F and ice massage to head daily for 20 min for 45 days. Patients were assessed using headache impact test (HIT, visual analog scale for pain and cardiac autonomic function by heart rate variability (HRV before and after intervention period. Results: There was a significant decrease in HIT score, frequency, and intensity of headaches following treatment in both the groups. However, it was more evident in add on hydrotherapy group compared to pharmacological treatment alone group. There was also significant improvement in the HRV parameters. In particular, there was a significant decrease in heart rate (P = 0.017, increase in high frequency (HF (P = 0.014 and decrease in low frequency/HF ratio (P = 0.004 in add on hydrotherapy group. Conclusion: Our study shows that add on hydrotherapy enhanced the vagal tone in addition to reducing the frequency and intensity of headaches in migraine patients.

Effects of Weekly Low-Frequency rTMS on Autonomic Measures in Children with Autism Spectrum Disorder

Directory of Open Access Journals (Sweden)

Manuel Fernando Casanova

2014-10-01

Full Text Available The term autism spectrum disorder (ASD describes a range of conditions characterized by impairments in social interactions, communication, and by restricted and repetitive behaviors. ASD may also present with symptoms suggestive of autonomic nervous system (ANS dysfunction. The objective of this study was to determine the effect of 18 sessions of low frequency repetitive transcranial magnetic stimulation (rTMS on autonomic function in children with ASD by recording electrocardiogram (EKG and electrodermal activity pre-, post- and during each rTMS session. The autonomic measures of interest in this study were R-R cardiointervals in EKG (R-R, time and frequency domain measures of heart rate variability (HRV and skin conductance level (SCL. HRV measures such as R-R intervals, standard deviation of cardiac intervals, pNN50 (percentage of cardiointervals>50 ms different from preceding interval, power of high frequency (HF and low frequency (LF components of HRV spectrum, LF/HF ratio, were then derived from the recorded EKG. We expected that the course of 18 weekly inhibitory low-frequency rTMS applied to the dorsolateral prefrontal cortex (DLPFC would enhance autonomic balance by facilitating frontal inhibition of limbic activity thus resulting in decreased overall heart rate, increased HRV (in a form of increased HF power, decreased LF power (resulting in decreased LF/HF ratio, and decreased SCL. Behavioral evaluations post-18 TMS showed decreased irritability, hyperactivity, stereotype behavior and compulsive behavior ratings while autonomic measures indicated a significant increase in cardiac interval variability and a decrease of tonic SCL. The results suggest that 18 sessions of low frequency rTMS in ASD results in increased cardiac vagal control and reduced sympathetic arousal.

Are Cardiac Autonomic Nervous System Activity and Perceived Stress Related to Functional Somatic Symptoms in Adolescents? The TRAILS Study

NARCIS (Netherlands)

Janssens, Karin A. M.; Riese, Harriëtte; van Roon, Arie M.; Hunfeld, Joke A. M.; Groot, Paul F. C.; Oldehinkel, Albertine J.; Rosmalen, Judith G. M.

2016-01-01

Stressors have been related to medically insufficiently explained or functional somatic symptoms (FSS). However, the underlying mechanism of this association is largely unclear. In the current study, we examined whether FSS are associated with different perceived stress and cardiac autonomic nervous

Cycling before and after Exhaustion Differently Affects Cardiac Autonomic Control during Heart Rate Matched Exercise

Directory of Open Access Journals (Sweden)

Matthias Weippert

2017-11-01

Full Text Available During cycling before (PRE and after exhaustion (POST different modes of autonomic cardiac control might occur due to different interoceptive input and altered influences from higher brain centers. We hypothesized that heart rate variability (HRV is significantly affected by an interaction of the experimental period (PRE vs. POST and exercise intensity (HIGH vs. LOW; HIGH = HR > HR at the lactate threshold (HRLT, LOW = HR ≤ HRLT despite identical average HR.Methods: Fifty healthy volunteers completed an incremental cycling test until exhaustion. Workload started with 30 W at a constant pedaling rate (60 revolutions · min−1 and was gradually increased by 30 W · 5 min−1. Five adjacent 60 s inter-beat (R-R interval segments from the immediate recovery period (POST 1–5 at 30 W and 60 rpm were each matched with their HR-corresponding 60 s-segments during the cycle test (PRE 1–5. An analysis of covariance was carried out with one repeated-measures factor (PRE vs. POST exhaustion, one between-subject factor (HIGH vs. LOW intensity and respiration rate as covariate to test for significant effects (p < 0.050 on the natural log-transformed root mean square of successive differences between adjacent R-R intervals (lnRMSSD60s.Results: LnRMSSD60s was significantly affected by the interaction of experimental period × intensity [F(1, 242 = 30.233, p < 0.001, ηp2 = 0.111]. LnRMSSD60s was higher during PRE compared to POST at LOW intensity (1.6 ± 0.6 vs. 1.4 ± 0.6 ms; p < 0.001. In contrast, at HIGH intensity lnRMSSD60s was lower during PRE compared to POST (1.0 ± 0.4 vs. 1.2 ± 0.4 ms; p < 0.001.Conclusion: Identical net HR during cycling can result from distinct autonomic modulation patterns. Results suggest a pronounced sympathetic-parasympathetic coactivation immediately after the cessation of peak workload compared to HR-matched cycling before exhaustion at HIGH intensity. On the opposite, at LOW intensity cycling, a stronger coactivational

CARDIAC AUTONOMIC NEUROPATHY AND MICROALBUMINURIA IN TYPE 2 DIABETES MELLITUS- A CROSS-SECTIONAL ANALYSIS

Directory of Open Access Journals (Sweden)

Suresh Padmini

2017-02-01

Full Text Available BACKGROUND Autonomous neuropathy is one of the least focused complications of type 2 diabetes mellitus in clinical practice. CAN is a significant cause of morbidity and mortality associated with a high risk of cardiac arrhythmias and sudden death. Higher urinary albumin excretion has been suggested as a predicting diabetic nephropathy. This cross-sectional study sought to determine relationship of CAN with early renal decline in type 2 diabetes mellitus. MATERIALS AND METHODS Over a period of two years, patients with type 2 diabetes mellitus after careful exclusion of other risk factors for proteinuria, 199 patients were included in this cross-sectional survey. CAN was measured by portable ANSiscope and 24-hour urine microalbumin level was estimated. Correlation was sought between the two variable. RESULTS Out of the 199 patients chosen for the study, 127 were male. The mean age of diabetes was 6.4±3.9 years. 57.8% had late or advanced CAN and there was a significant linear correlation with 24-hour urine microalbumin levels. CONCLUSION Measurement of CAN is an effective way to assess the level of cardiac sympathetic dysfunction due to disease in patients with type 2 diabetes mellitus of more than 5 years duration. Urine microalbumin levels correlate with the degree of CAN. There is a strong need to conduct more studies about CAN to fully understand its pathology and develop treatment strategies to reduce cardiac mortality.

Blood pressure and cardiac autonomic modulation at rest, during exercise and recovery time in the young overweight

Directory of Open Access Journals (Sweden)

Jaqueline Alves de Araújo

2016-03-01

Full Text Available Abstract This study aimed to assess the blood pressure (BP, cardiac autonomic modulation at rest, in physical exercise and in the recovery in untrained eutrophic (E and overweight (O youth. The body mass index (BMI, waist circumference (WC, systolic BP-SBP (E: 109.80 ± 10.05; O: 121.85 ± 6.98 mmHg and diastolic BP - DBP (E: 65.90 ± 7.28; O: 73.14 ± 12.22 mmHg were higher in overweight and the heart rate recovery (%HRR was lower as compared with E volunteers. The BMI was associated with SBP (r= 0.54, DBP (r= 0.65, load on the heart rate variability threshold - HRVT (r= -0.46, %HRR 2' (r= -0.48 and %HRR 5' (r= -0.48, and WC was associated with SBP (r= 0.54, DBP (r= 0.64 and HRR 2' (r= -0.49. The %HRR was associated to SBP, DBP and HRVT. In summary, the anthropometric variables, BP and cardiac autonomic modulation in the recovery are altered in overweight youth.

CAPSAICIN SUPPLEMENTATION FAILS TO MODULATE AUTONOMIC AND CARDIAC ELECTROPHYSIOLOGIC ACTIVITY DURING EXERCISE IN THE OBESE: WITH VARIANTS OF UCP2 AND UCP3 POLYMORPHISM

Directory of Open Access Journals (Sweden)

Ki Ok Shin

2008-09-01

Full Text Available We investigated the effects of capsaicin supplementation (150mg on alterations of autonomic nervous system (ANS activity associated with adverse effects of cardiac depolarization-repolarization intervals during aerobic exercise in obese humans. Nine obese males (26.1 ± 1.5 yrs volunteered between study designed. The cardiac ANS activities evaluated by means of heart rate variability of power spectral analysis and cardiac QT interval were continuously measured during 5-min rest and 30-min exercise at 50% of maximal ventilation threshold (50%VTmax on stationary ergometer with placebo (CON or capsaicin (CAP oral administration chosen at random. The uncoupling protein (UCP 2 and UCP 3 genetic variants of the subjects were analyzed by noninvasive genotyping method from collecting buccal mucosa cells. The results indicated that there were no significant differences in cardiac ANS activities during rest and exercise between CON and CAP trials. Although no significant difference, A/A allele of UCP2 polymorphism showed a reduced sympathetic nervous system (SNS index activity compared to G/G + G/A allele during exercise intervention in our subjects. On the other hand, the data on cardiac QT interval showed no significant difference, indicating that oral administration of capsaicin did not cause any adverse effect on cardiac depolarization-repolarization. In conclusion, our results suggest that capsaicin supplementation 1 h before exercise intervention has no effect on cardiac ANS activities and cardiac electrical stability during exercise in obese individuals. Further studies should also consider genetic variants for exercise efficacy against obesity

Cardiac Autonomic and Blood Pressure Responses to an Acute Bout of Kettlebell Exercise.

Science.gov (United States)

Wong, Alexei; Nordvall, Michael; Walters-Edwards, Michelle; Lastova, Kevin; Francavillo, Gwendolyn; Summerfield, Liane; Sanchez-Gonzalez, Marcos

2017-10-07

Kettlebell (KB) training has become an extremely popular exercise program for improving both muscle strength and aerobic fitness. However, the cardiac autonomic modulation and blood pressure (BP) responses induced by an acute KB exercise session are currently unknown. Understanding the impact of this exercise modality on the post-exercise autonomic modulation and BP would facilitate appropriate exercise prescription in susceptible populations. The present study evaluated the effects of an acute session of KB exercise on heart rate variability (HRV) and BP responses in healthy individuals. Seventeen (M=10, F=7) healthy subjects completed either a KB or non-exercise control trial in randomized order. HRV and BP measurements were collected at baseline, 3, 10 and 30 min after each trial. There were significant increases (P < 0.01) in heart rate, markers of sympathetic activity (nLF) and sympathovagal balance (nLF/nHF) for 30 min after the trial KB trial, while no changes from baseline were observed after the control trial. There were also significant decreases (P < 0.01) in markers of vagal tone (RMMSD, nHF) for 30 min as well as (P < 0.01) systolic BP and diastolic BP at 10 and 30 min after the trial KB trial while no changes from baseline were observed after the control trial. Our findings indicate that KB exercise increases sympathovagal balance for 30 min post-intervention which is concurrent with an important hypotensive effect. Further research is warranted to evaluate the potential clinical application of KB training in populations that might benefit from post-exercise hypotension, such as hypertensives.

Quantifying Effects of Pharmacological Blockers of Cardiac Autonomous Control Using Variability Parameters.

Science.gov (United States)

Miyabara, Renata; Berg, Karsten; Kraemer, Jan F; Baltatu, Ovidiu C; Wessel, Niels; Campos, Luciana A

2017-01-01

Objective: The aim of this study was to identify the most sensitive heart rate and blood pressure variability (HRV and BPV) parameters from a given set of well-known methods for the quantification of cardiovascular autonomic function after several autonomic blockades. Methods: Cardiovascular sympathetic and parasympathetic functions were studied in freely moving rats following peripheral muscarinic (methylatropine), β1-adrenergic (metoprolol), muscarinic + β1-adrenergic, α1-adrenergic (prazosin), and ganglionic (hexamethonium) blockades. Time domain, frequency domain and symbolic dynamics measures for each of HRV and BPV were classified through paired Wilcoxon test for all autonomic drugs separately. In order to select those variables that have a high relevance to, and stable influence on our target measurements (HRV, BPV) we used Fisher's Method to combine the p -value of multiple tests. Results: This analysis led to the following best set of cardiovascular variability parameters: The mean normal beat-to-beat-interval/value (HRV/BPV: meanNN), the coefficient of variation (cvNN = standard deviation over meanNN) and the root mean square differences of successive (RMSSD) of the time domain analysis. In frequency domain analysis the very-low-frequency (VLF) component was selected. From symbolic dynamics Shannon entropy of the word distribution (FWSHANNON) as well as POLVAR3, the non-linear parameter to detect intermittently decreased variability, showed the best ability to discriminate between the different autonomic blockades. Conclusion: Throughout a complex comparative analysis of HRV and BPV measures altered by a set of autonomic drugs, we identified the most sensitive set of informative cardiovascular variability indexes able to pick up the modifications imposed by the autonomic challenges. These indexes may help to increase our understanding of cardiovascular sympathetic and parasympathetic functions in translational studies of experimental diseases.

Effects of prefrontal rTMS on autonomic reactions to affective pictures.

Science.gov (United States)

Berger, Christoph; Domes, Gregor; Balschat, Johannes; Thome, Johannes; Höppner, Jacqueline

2017-02-01

Repetitive transcranial magnetic stimulation (rTMS) can modulate the excitability of stimulated cortical areas, such as prefrontal areas involved in emotion regulation. Low frequency (LF) rTMS is expected to have inhibitory effects on prefrontal regions, and thereby should disinhibit limbic activity, resulting in enhanced emotional and autonomic reactions. For high frequency (HF) rTMS, the opposite pattern might be assumed. The objective of this study was to determine the effects of different rTMS frequencies applied to the right dlPFC on autonomic functions and on emotional perception. In a crossover design, two groups of 20 healthy young women were either stimulated with one session of LF rTMS (1 Hz) or one session of HF rTMS (10 Hz), compared to sham stimulation. We assessed phasic cardiac responses (PCR), skin conductance reactions (SCR), and emotional appraisal of emotional pictures as well as recognition memory after each rTMS application. After LF rTMS, PCR (heart rate deceleration) during presentation of pictures with negative and neutral valence was significantly increased compared to the presentation of positive pictures. In contrast, the modulatory effect of picture valence and arousal on the cardiac orienting response was absent after HF rTMS. Our results suggest that frontal LF rTMS indirectly activates the ANS via inhibition of the right dlPFC activity, likely by enhancing the sensory processing or attention to aversive and neutral stimuli.

Cardiac Autonomic Neuropathy Predicts All-Cause and Cardiovascular Mortality in Patients With End-Stage Renal Failure: A 5-Year Prospective Study

Directory of Open Access Journals (Sweden)

Dimitrios Doulgerakis

2017-07-01

Discussion: Age and presence of CAN are independent predictors of all-cause and CV mortality in patients with ESRF. The functionality of the cardiac autonomic nervous system activity can be used for the risk stratification in patients with ESRF.

Sensitivity Analysis of Vagus Nerve Stimulation Parameters on Acute Cardiac Autonomic Responses: Chronotropic, Inotropic and Dromotropic Effects.

Directory of Open Access Journals (Sweden)

David Ojeda

Full Text Available Although the therapeutic effects of Vagus Nerve Stimulation (VNS have been recognized in pre-clinical and pilot clinical studies, the effect of different stimulation configurations on the cardiovascular response is still an open question, especially in the case of VNS delivered synchronously with cardiac activity. In this paper, we propose a formal mathematical methodology to analyze the acute cardiac response to different VNS configurations, jointly considering the chronotropic, dromotropic and inotropic cardiac effects. A latin hypercube sampling method was chosen to design a uniform experimental plan, composed of 75 different VNS configurations, with different values for the main parameters (current amplitude, number of delivered pulses, pulse width, interpulse period and the delay between the detected cardiac event and VNS onset. These VNS configurations were applied to 6 healthy, anesthetized sheep, while acquiring the associated cardiovascular response. Unobserved VNS configurations were estimated using a Gaussian process regression (GPR model. In order to quantitatively analyze the effect of each parameter and their combinations on the cardiac response, the Sobol sensitivity method was applied to the obtained GPR model and inter-individual sensitivity markers were estimated using a bootstrap approach. Results highlight the dominant effect of pulse current, pulse width and number of pulses, which explain respectively 49.4%, 19.7% and 6.0% of the mean global cardiovascular variability provoked by VNS. More interestingly, results also quantify the effect of the interactions between VNS parameters. In particular, the interactions between current and pulse width provoke higher cardiac effects than the changes on the number of pulses alone (between 6 and 25% of the variability. Although the sensitivity of individual VNS parameters seems similar for chronotropic, dromotropic and inotropic responses, the interacting effects of VNS parameters

Comparative study of short-term cardiovascular autonomic control in cardiac surgery patients who underwent coronary artery bypass grafting or correction of valvular heart disease.

Science.gov (United States)

Shvartz, Vladimir A; Kiselev, Anton R; Karavaev, Anatoly S; Vulf, Kristina A; Borovkova, Ekaterina I; Prokhorov, Mikhail D; Petrosyan, Andrey D; Bockeria, Olga L

2018-01-01

Introduction: Our aim was to perform a comparative study of short-term cardiovascular autonomic control in cardiac surgery patients who underwent coronary artery bypass grafting (CABG) or surgical correction of valvular heart disease (SCVHD ). Methods: The synchronous 15 minutes records of heart rate variability (HRV) and finger's photoplethysmographic waveform variability (PPGV) were performed in 42 cardiac surgery patients (12 women) aged 61.8 ± 8.6 years (mean ± standard deviation), who underwent CABG, and 36 patients (16 women) aged 54.2 ± 14.9 years, who underwent SCVHD , before surgery and in 5-7 days after surgery. Conventional time and frequency domain measures of HRV and index S of synchronization between the slow oscillations in PPGV and HRV were analyzed. We also calculated personal dynamics of these indices after surgery. Results: We found no differences ( Р > 0.05) in all studied autonomic indices (preoperative and post-surgery) between studied patients' groups, except for the preoperative heart rate, which was higher in patients who underwent SCVHD ( P = 0.013). We have shown a pronounced preoperative and post-surgery variability (magnitude of inter-quartile ranges) of all autonomic indices in studied patients. In the cluster analysis based on cardiovascular autonomic indices (preoperative and post-surgery), we divided all patients into two clusters (38 and 40 subjects) which did not differ in all clinical characteristics (except for the preoperative hematocrit, P = 0.038), index S, and all post-surgery HRV indices. First cluster (38 patients) had higher preoperative values of the HR, TP, HF, and HF%, and lower preoperative values of the LF% and LF/HF. Conclusion: The variability of cardiovascular autonomic indices in on-pump cardiac surgery patients (two characteristic clusters were identified based on preoperative indices) was not associated with their clinical characteristics and features of surgical procedure (including cardioplegia).

Regular physical exercise improves cardiac autonomic and muscle vasodilatory responses to isometric exercise in healthy elderly

Directory of Open Access Journals (Sweden)

Sarmento AO

2017-06-01

Full Text Available Adriana de Oliveira Sarmento,1–3 Amilton da Cruz Santos,1,4 Ivani Credidio Trombetta,2,5 Marciano Moacir Dantas,1 Ana Cristina Oliveira Marques,1,4 Leone Severino do Nascimento,1,4 Bruno Teixeira Barbosa,1,2 Marcelo Rodrigues Dos Santos,2 Maria do Amparo Andrade,3 Anna Myrna Jaguaribe-Lima,3,6 Maria do Socorro Brasileiro-Santos1,3,4 1Laboratory of Physical Training Studies Applied to Health, Department of Physical Education, Federal University of Paraiba, João Pessoa, Brazil; 2Unit of Cardiovascular Rehabilitation and Exercise Physiology – Heart Institute (InCor/HC-FMUSP, University of São Paulo, São Paulo, Brazil; 3Graduate Program in Physiotherapy, Federal University of Pernambuco, Recife, Brazil; 4Associate Graduate Program in Physical Education UPE/UFPB, João Pessoa, Brazil; 5Graduate Program in Medicine, Universidade Nove de Julho (UNINOVE, São Paulo, Brazil; 6Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco, Recife, Brazil Abstract: The objective of this study was to evaluate cardiac autonomic control and muscle vasodilation response during isometric exercise in sedentary and physically active older adults. Twenty healthy participants, 10 sedentary and 10 physically active older adults, were evaluated and paired by gender, age, and body mass index. Sympathetic and parasympathetic cardiac activity (spectral and symbolic heart rate analysis and muscle blood flow (venous occlusion plethysmography were measured for 10 minutes at rest (baseline and during 3 minutes of isometric handgrip exercise at 30% of the maximum voluntary contraction (sympathetic excitatory maneuver. Variables were analyzed at baseline and during 3 minutes of isometric exercise. Cardiac autonomic parameters were analyzed by Wilcoxon and Mann–Whitney tests. Muscle vasodilatory response was analyzed by repeated-measures analysis of variance followed by Tukey’s post hoc test. Sedentary older adults had higher cardiac

Cardiac autonomic tone during trandolapril-irbesartan low-dose combined therapy in hypertension: a pilot project.

Science.gov (United States)

Franchi, F; Lazzeri, C; Foschi, M; Tosti-Guerra, C; Barletta, G

2002-08-01

Pharmacological and clinical studies on the effects of angiotensin-converting enzyme (ACE) inhibitors support the idea of a central role played Angiotensin II which is able to cause cardiovascular and renal diseases also independently of its blood pressure elevating effects. The present investigation was aimed at evaluating the effect(s) of three different pharmacological regimens on both blood pressure and sympathetic drive in uncomplicated essential hypertension, by means of blood pressure laboratory measurements and ambulatory monitoring, 24-h heart rate variability and plasma noradrenaline levels. Thus, an ACE-inhibitor monotherapy (trandolapril, 2 mg/day), an AT(1)-receptor antagonist monotherapy (irbesartan, 300 mg/day), their low-dose combination (0.5 mg/day plus 150 mg/day, respectively) and placebo were given, in a randomised, single-blind, crossover fashion for a period of 3 weeks each to 12 mild essential hypertensives. Power spectral analysis (short recordings) and noradrenaline measurements were also performed in the supine position and after a postural challenge (60 degrees head-up tilting test: HUT). The low-dose combination therapy induced the greatest reduction in LF component and in LF/HF ratio, both in the resting and tilted positions, as well as in blood pressure. However, the physiological autonomic response to HUT was maintained. Noradrenaline plasma levels were lower after the combined therapy than after each drug alone. Our data demonstrate that in mild and uncomplicated essential hypertension, the chronic low-dose combination therapy with an ACE-inhibitor and an AT(1)-antagonist is more effective than the recommended full-dose monotherapy with either drug in influencing the autonomic regulation of the heart, suggesting a relative reduction in sympathetic drive both at cardiac and systemic levels.

Aging in autonomic control by multifractal studies of cardiac interbeat intervals in the VLF band

International Nuclear Information System (INIS)

Makowiec, Danuta; Kryszewski, Stanisław; Rynkiewicz, Andrzej; Wdowczyk-Szulc, Joanna; Żarczyńska-Buchowiecka, Marta; Gałąska, Rafał

2011-01-01

The heart rate responds dynamically to various intrinsic and environmental stimuli. The autonomic nervous system is said to play a major role in this response. Multifractal analysis offers a novel method to assess the response of cardiac interbeat intervals. Twenty-four hour ECG recordings of RR interbeat intervals (of 48 elderly volunteers (age 65–94), 40 middle-aged persons (age 45–53) and 36 young adults (age 18–26)) were investigated to study the effect of aging on autonomic regulation during normal activity in healthy adults. Heart RR-interval variability in the very low frequency (VLF) band (32–420 RR intervals) was evaluated by multifractal tools. The nocturnal and diurnal signals of 6 h duration were studied separately. For each signal, the analysis was performed twice: for a given signal and for the integrated signal. A multifractal spectrum was quantified by the h max value at which a multifractal spectrum attained its maximum, width of a spectrum, Hurst exponent, extreme events h left and distance between the maxima of a signal and its integrated counterpart. The following seven characteristics are suggested as quantifying the age-related decrease in the autonomic function ('int' refers to the integrated signal): (a) h sleep max − h max wake > 0.05 for a signal; (b) h int max > 1.15 for wake; (c) h int max − h max > 0.85 for sleep; (d) Hurst wake − Hurst sleep < 0.01; (e) width wake > 0.07; (f) width int < 0.30 for sleep; (g) h int left > 0.75. Eighty-one percent of elderly people had at least four of these properties, and ninety-two percent of young people had three or less. This shows that the multifractal approach offers a concise and reliable index of healthy aging for each individual. Additionally, the applied method yielded insights into dynamical changes in the autonomic regulation due to the circadian cycle and aging. Our observations support the hypothesis that imbalance in the autonomic control due to healthy aging could

Limits of clinical tests to screen autonomic function in diabetes type 1.

Science.gov (United States)

Ducher, M; Bertram, D; Sagnol, I; Cerutti, C; Thivolet, C; Fauvel, J P

2001-11-01

A precocious detection of cardiac autonomic dysfunction is of major clinical interest that could lead to a more intensive supervision of diabetic patients. However, classical clinical exploration of cardiac autonomic function is not easy to undertake in a reproducible way. Thus, respective interests of autonomic nervous parameters provided by both clinical tests and computerized analysis of resting blood pressure were checked in type 1 diabetic patients without orthostatic hypotension and microalbuminuria. Thirteen diabetic subjects matched for age and gender to thirteen healthy subjects volunteered to participate to the study. From clinical tests (standing up, deep breathing, Valsalva maneuver, handgrip test), autonomic function was scored according to Ewing's methodology. Analysis of resting beat to beat blood pressure provided autonomic indices of the cardiac function (spectral analysis or Z analysis). 5 of the 13 diabetic patients exhibited a pathological score (more than one pathological response) suggesting the presence of cardiovascular autonomic dysfunction. The most discriminative test was the deep breathing test. However, spectral indices of BP recordings and baro-reflex sensitivity (BRS) of these 5 subjects were similar to those of healthy subjects and of remaining diabetic subjects. Alteration in Ewing's score given by clinical tests may not reflect an alteration of cardiac autonomic function in asymptomatic type 1 diabetic patients, because spectral indices of sympathetic and parasympathetic (including BRS) function were within normal range. Our results strongly suggest to confront results provided by both methodologies before concluding to an autonomic cardiac impairment in asymptomatic diabetic patients.

Cardiac Autonomic and Blood Pressure Responses to an Acute Foam Rolling Session.

Science.gov (United States)

Lastova, Kevin; Nordvall, Michael; Walters-Edwards, Michelle; Allnutt, Amy; Wong, Alexei

2018-03-22

Foam Rolling (FR) is a self-myofascial release method that has become extremely popular among athletes and fitness enthusiasts for its ability to improve flexibility and range of motion and alleviate delayed onset muscle soreness. However, the cardiac autonomic modulation and blood pressure (BP) responses induced by an acute FR session are currently unknown. The present study evaluated the effects of an acute session of FR exercise on heart rate variability (HRV) and BP responses in healthy individuals. Fifteen (M=8, F=7) healthy subjects completed either a FR or non-exercise control trial in randomized order. HRV and BP measurements were collected at baseline, 10 and 30 min after each trial. There were significant increases (P < 0.01) in markers of vagal tone (nHF) for 30 min after the FR trial, while no changes from baseline were observed following control. There were also significant decreases (P < 0.05) in markers of sympathetic activity (nLF), sympathovagal balance (nLF/nHF), systolic BP and diastolic BP at 10 and 30 min after the trial KB trial while no changes from baseline were observed after the control trial. Our findings indicate that FR decreases sympathovagal balance for 30 min post-intervention which is concurrent with an important hypotensive effect. Further research is warranted to evaluate the potential cardiovascular protective effects of FR in diverse populations.

Impact of traffic-related air pollution on acute changes in cardiac autonomic modulation during rest and physical activity: a cross-over study.

Science.gov (United States)

Cole-Hunter, Tom; Weichenthal, Scott; Kubesch, Nadine; Foraster, Maria; Carrasco-Turigas, Glòria; Bouso, Laura; Martínez, David; Westerdahl, Dane; de Nazelle, Audrey; Nieuwenhuijsen, Mark

2016-01-01

People are often exposed to traffic-related air pollution (TRAP) during physical activity (PA), but it is not clear if PA modifies the impact of TRAP on cardiac autonomic modulation. We conducted a panel study among 28 healthy adults in Barcelona, Spain to examine how PA may modify the impact of TRAP on cardiac autonomic regulation. Participants completed four 2-h exposure scenarios that included either rest or intermittent exercise in high- and low-traffic environments. Time- and frequency-domain measures of heart rate variability (HRV) were monitored during each exposure period along with continuous measures of TRAP. Linear mixed-effects models were used to estimate the impact of TRAP on HRV as well as potential effect modification by PA. Exposure to TRAP was associated with consistent decreases in HRV; however, exposure-response relationships were not always linear over the broad range of exposures. For example, each 10 μg/m(3) increase in black carbon was associated with a 23% (95% CI: -31, -13) decrease in high frequency power at the low-traffic site, whereas no association was observed at the high-traffic site. PA modified the impact of TRAP on HRV at the high-traffic site and tended to weaken inverse associations with measures reflecting parasympathetic modulation (P ≤ 0.001). Evidence of effect modification at the low-traffic site was less consistent. The strength and direction of the relationship between TRAP and HRV may vary across exposure gradients. PA may modify the impact of TRAP on HRV, particularly at higher concentrations.

Synergistic effect of energy drinks and overweight/obesity on cardiac autonomic testing using the Valsalva maneuver in university students.

Science.gov (United States)

Majeed, Farrukh; Yar, Talay; Alsunni, Ahmed; Alhawaj, Ali Fouad; AlRahim, Ahmed; Alzaki, Muneer

2017-01-01

Obesity and caffeine consumption may lead to autonomic disturbances that can result in a wide range of cardiovascular disorders. To determine autonomic disturbances produced by the synergistic effects of overweight or obesity (OW/OB) and energy drinks. Cross-sectional, analytical. Physiology department at a university in Saudi Arabia. University students, 18-22 years of age, of normal weight (NW) and OW/OB were recruited by convenience sampling. Autonomic testing by the Valsalva ratio (VR) along with systolic and diastolic blood pressure, pulse pressure, and mean arterial blood pressure were measured at baseline (0 minute) and 60 minutes after energy drink consumption. Autonomic disturbance, hemodynamic changes. In 50 (27 males and 23 females) subjects, 21 NW and 29 OW/OB, a significant decrease in VR was observed in OW/OB subjects and in NW and OW/OB females at 60 minutes after energy drink consumption. Values of systolic and diastolic blood pressure, pulse pressure and mean arterial blood pressure were also significantly higher in OW/OB and in females as compared to NW and males. BMI was negatively correlated with VR and diastolic blood pressure at 60 minutes. Obesity and energy drinks alter autonomic functions. In some individuals, OW/OB may augment these effects. Due to time and resource restraints, only the acute effects of energy drinks were examined.

Social stress contagion in rats: Behavioural, autonomic and neuroendocrine correlates.

Science.gov (United States)

Carnevali, Luca; Montano, Nicola; Statello, Rosario; Coudé, Gino; Vacondio, Federica; Rivara, Silvia; Ferrari, Pier Francesco; Sgoifo, Andrea

2017-08-01

The negative emotional consequences associated with life stress exposure in an individual can affect the emotional state of social partners. In this study, we describe an experimental rat model of social stress contagion and its effects on social behaviour and cardiac autonomic and neuroendocrine functions. Adult male Wistar rats were pair-housed and one animal (designated as "demonstrator" (DEM)) was submitted to either social defeat stress (STR) by an aggressive male Wild-type rat in a separate room or just exposed to an unfamiliar empty cage (control condition, CTR), once a day for 4 consecutive days. We evaluated the influence of cohabitation with a STR DEM on behavioural, cardiac autonomic and neuroendocrine outcomes in the cagemate (defined "observer" (OBS)). After repeated social stress, STR DEM rats showed clear signs of social avoidance when tested in a new social context compared to CTR DEM rats. Interestingly, also their cagemate STR OBSs showed higher levels of social avoidance compared to CTR OBSs. Moreover, STR OBS rats exhibited a higher heart rate and a larger shift of cardiac autonomic balance toward sympathetic prevalence (as indexed by heart rate variability analysis) immediately after the first reunification with their STR DEMs, compared to the control condition. This heightened cardiac autonomic responsiveness habituated over time. Finally, STR OBSs showed elevated plasma corticosterone levels at the end of the experimental protocol compared to CTR OBSs. These findings demonstrate that cohabitation with a DEM rat, which has experienced repeated social defeat stress, substantially disrupts social behaviour and induces short-lasting cardiac autonomic activation and hypothalamic-pituitary-adrenal axis hyperactivity in the OBS rat, thus suggesting emotional state-matching between the OBS and the DEM rats. We conclude that this rodent model may be further exploited for investigating the neurobiological bases of negative affective sharing between

Relationship between inflammatory and coagulation biomarkers and cardiac autonomic function in HIV-infected individuals

DEFF Research Database (Denmark)

Young, Lari C; Roediger, Mollie P; Grandits, Greg

2014-01-01

Therapy study. We examined the association between IL-6, high-sensitivity C-reactive protein (hsCRP) and D-dimer with heart rate variability measures (SDNN and rMSSD), both cross-sectionally and longitudinally. RESULTS: Cross-sectional analysis revealed significant inverse associations between IL-6, hs......CRP and d-dimer with SDNN and rMSSD (p Cross-sectionally, higher levels of inflammatory and coagulation biomarkers were......AIM: To examine the relationship between inflammatory and coagulation biomarkers and cardiac autonomic function (CAF) as measured by heart rate variability in persons with HIV. MATERIALS & METHODS: This analysis included 4073 HIV-infected persons from the Strategies for Management of Antiretroviral...

AUTONOMIC NERVOUS ACTIVITY AND LIPID OXIDATION POSTEXERCISE WITH CAPSAICIN IN THE HUMANS

Directory of Open Access Journals (Sweden)

Ki Ok Shin

2010-06-01

Full Text Available This study evaluated the synergistic effects of acute exercise with capsaicin (200mg upon the restoration of cardiac autonomic functions and depolarization- repolarization interval as well as substrate oxidation. Nine healthy males [21.9(0.8 yrs] volunteered for this study. Cardiac autonomic activity, metabolic responses, and the ECG QT intervals were continuously measured during 5 min at rest and postexercise recovery after 30 min exercise at 50% VO2max on a stationary ergometer with placebo (ECON or capsaicin intake (ECAP, and no exercise control (NCON were randomized. Results indicated that the HF power reflecting parasympathetic activity significantly returned to the baseline much faster during ECAP than ECON trial during postexercise [122.1 (23.2 vs. 60.2 (11.7 %, p < 0.05]. The ECAP trial significantly decreased RQ [0.79(0.02 vs. 0.85 (0.03, p < 0.05] with significantly greater fat oxidation [69.3 (6.0 vs. 49.4 (10.8 %, p < 0.05] in comparison to NCON trial during 120 min postexercise recovery without any adverse effects on cardiac electrical stability as determined by trigger-averaged ECG QT interval analyses. We suggest that capsaicin before the exercise may contribute to the improvement of cardio-protective functions and metabolic responses as one of the beneficial supplements accelerating faster restoration of autonomic activity and enhanced lipolysis during postexercise recovery without any adverse effects on cardiac electrical stability

Cardiac autonomic function during sleep: effects of alcohol dependence and evidence of partial recovery with abstinence.

Science.gov (United States)

de Zambotti, Massimiliano; Willoughby, Adrian R; Baker, Fiona C; Sugarbaker, David S; Colrain, Ian M

2015-06-01

Chronic alcoholism is associated with the development of cardiac and peripheral autonomic nervous system (ANS) pathology. The aim of the present study was to evaluate the extent to which recovery in ANS function could be demonstrated over the first 4 months of abstinence. Fifteen alcoholics (7 women) were studied on three occasions: within a month of detoxification, at approximately 2 months post-detox, and at 4 months post-detox. Thirteen control subjects (6 women) were also studied on three occasions with inter-study intervals matching those of the alcoholics. Six alcoholics relapsed, 48.7 ± 27.9 days following the initial PSG session. ANS function was assessed in the first part of stable non-rapid eye movement sleep. Frequency-domain power spectral analysis of heart rate variability (HRV) produced variables including: heart rate (HR), total power (TP; an index representing total HR variability), High Frequency power (HFa; an index reflecting cardiac vagal modulation), HF proportion of total power (HFprop sympathovagal balance), and HF peak frequency (HFpf; an index reflecting respiration rate). Overall, high total and high frequency variability and low sympathovagal balance and myocardial contractility are considered as desired conditions to promote cardiovascular health. At initial assessment, alcoholics had a higher HR (p < 0.001) and respiratory rate (p < 0.01), and lower vagal activity (HFa; p < 0.01) than controls. Alcoholics showed evidence of recovery in HR (p = 0.039) and HFa (p = 0.031) with 4 months of abstinence. Alcoholics with higher TP at the initial visit showed a greater improvement in TP from the initial to the 4 month follow-up session (r = 0.75, p < 0.05). Alcoholics showed substantial recovery in HR and vagal modulation of HRV with 4 months of abstinence, with evidence that the extent of recovery in HRV may be partially determined by the extent of alcohol dependence-related insult to the cardiac ANS system. These data support other studies

Impact of a soccer match on the cardiac autonomic control of referees.

Science.gov (United States)

Boullosa, Daniel Alexandre; Abreu, Laurinda; Tuimil, José Luis; Leicht, Anthony Scott

2012-06-01

The purpose of this study was to assess the effect of a soccer match on the cardiac autonomic control of heart rate (HR) in soccer referees. Sixteen Spanish regional and third division referees (11 males: 26 ± 7 years, 74.4 ± 4.1 kg, 178 ± 3 cm, Yo-Yo IR1 ~600-1,560 m; 5 females: 22 ± 3 years, 59.3 ± 4.8 kg, 158 ± 8 cm, Yo-Yo IR1 ~200-520 m) participated with 24-h HR recordings measured with a Polar RS800 during a rest and a match day. Autonomic control of HR was assessed from HR variability (HRV) analysis. Inclusion of a soccer match (92.5% spent at >75% maximum HR) reduced pre-match (12:00-17:00 hours; small to moderate), post-match (19:00-00:00 hours; moderate to almost perfect), and night-time (00:00-05:00 hours; small to moderate) HRV. Various moderate-to-large correlations were detected between resting HRV and the rest-to-match day difference in HRV. The rest-to-match day differences of low and high-frequency bands ratio (LF/HF) and HR in the post-match period were moderately correlated with time spent at different exercise intensities. Yo-Yo IR1 performance was highly correlated with jump capacity and peak lactate, but not with any HRV parameter. These results suggest that a greater resting HRV may allow referees to tolerate stresses during a match day with referees who spent more time at higher intensities during matches exhibiting a greater LF/HF increment in the post-match period. The relationship between match activities, [Formula: see text] and HR recovery kinetics in referees and team sport athletes of different competitive levels remains to be clarified.

Synergistic effects of low-intensity exercise conditioning and β-blockade on cardiovascular and autonomic adaptation in pre- and postmenopausal women with hypertension.

Science.gov (United States)

Goldie, Catherine L; Brown, C Ann; Hains, Sylvia M J; Parlow, Joel L; Birtwhistle, Richard

2013-10-01

The effects of a 12-week low-intensity exercise conditioning program (walking) on blood pressure (BP), heart rate (HR), rate-pressure product (RPP), and cardiac autonomic function were measured in 40 sedentary women with hypertension. Women were assigned to either an exercise group (n = 20) or a control group (n = 20), matched for β-blockade treatment. They underwent testing at the beginning and at the end of the 12-week study period in three conditions: supine rest, standing, and low-intensity steady state exercise. The exercise group participated in a 12-week, low-intensity walking program, while the control group continued with usual sedentary activity. Compared with the control group, women in the exercise group showed reductions in systolic and diastolic BP and RPP (i.e., the estimated cardiac workload). β-Blockers increased baroreflex sensitivity and lowered BP and HR in all participants; however, those in the exercise group showed the effects of both treatments: a greater reduction in HR and RPP. The combination of exercise training and β-blockade produces cardiac and autonomic adaptations that are not observed with either treatment alone, suggesting that β-blockade enhances the conditioning effects of low-intensity exercise in women with hypertension.

Cardiac autonomic modulation by estrogen in female mice undergoing ambulatory monitoring and in vivo electrophysiologic testing.

Science.gov (United States)

Saba, Samir; Shusterman, Vladimir; Usiene, Irmute; London, Barry

2004-04-01

Estrogen is an important modulator of cardiovascular risk, but its mechanism of action is not fully understood. We investigated the effect of ovariectomy and its timing on the cardiac electrophysiology in mice. Thirty female mice (age 18.8 +/- 3.1 weeks) underwent in vivo electrophysiologic testing before and after autonomic blockade. Fifteen mice were ovariectomized prepuberty (PRE) and ten postpuberty (POST), 2 weeks prior to electrophysiologic testing. Five age-matched sham-operated female mice (Control) served as controls. A subset of 13 mice (5 PRE, 3 POST, and 5 Controls) underwent 24-hour ambulatory monitoring. With ambulatory monitoring, the average (668 +/- 28 vs 769 +/- 52 b/min, P = 0.008) and minimum (485 +/- 47 vs 587 +/- 53 b/min, P = 0.02) heart rates were significantly slower in the ovariectomized mice (PRE and POST groups) compared to the Control group. At baseline electrophysiologic testing, there were no significant differences among the ovariectomized and intact mice in any of the measured parameters. With autonomic blockade, the Control group had a significantly larger change (delta) in the atrioventricular (AV) nodal Wenckebach (AVW) periodicity (deltaAVW = 11.3 +/- 2.9 vs 2.1 +/- 7.3 ms, P = 0.05) and functional refractory period (deltaFRP = 11.3 +/- 2.1 vs 1.25 +/- 6.8 ms, P = 0.02) compared to the ovariectomized mice. These results were not altered by the time of ovariectomy (PRE vs POST groups). Our results suggest that estrogen modulates the autonomic inputs into the murine sinus and AV nodes. These findings, if replicated in humans, might underlie the observed clustering of certain arrhythmias around menstruation and explain the higher incidence of arrhythmias in men and postmenopausal women.

TRPA1 mediates changes in heart rate variability and cardiac mechanical function in mice exposed to acrolein

Energy Technology Data Exchange (ETDEWEB)

Kurhanewicz, Nicole [Curriculum in Toxicology, School of Medicine, University of North Carolina, Chapel Hill, NC 27599 (United States); McIntosh-Kastrinsky, Rachel [Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599 (United States); Tong, Haiyan; Ledbetter, Allen; Walsh, Leon; Farraj, Aimen [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Hazari, Mehdi, E-mail: hazari.mehdi@epa.gov [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC 27711 (United States)

2017-06-01

Short-term exposure to ambient air pollution is linked with adverse cardiovascular effects. While previous research focused primarily on particulate matter-induced responses, gaseous air pollutants also contribute to cause short-term cardiovascular effects. Mechanisms underlying such effects have not been adequately described, however the immediate nature of the response suggests involvement of irritant neural activation and downstream autonomic dysfunction. Thus, this study examines the role of TRPA1, an irritant sensory receptor found in the airways, in the cardiac response of mice to acrolein and ozone. Conscious unrestrained wild-type C57BL/6 (WT) and TRPA1 knockout (KO) mice implanted with radiotelemeters were exposed once to 3 ppm acrolein, 0.3 ppm ozone, or filtered air. Heart rate (HR) and electrocardiogram (ECG) were recorded continuously before, during and after exposure. Analysis of ECG morphology, incidence of arrhythmia and heart rate variability (HRV) were performed. Cardiac mechanical function was assessed using a Langendorff perfusion preparation 24 h post-exposure. Acrolein exposure increased HRV independent of HR, as well as incidence of arrhythmia. Acrolein also increased left ventricular developed pressure in WT mice at 24 h post-exposure. Ozone did not produce any changes in cardiac function. Neither gas produced ECG effects, changes in HRV, arrhythmogenesis, or mechanical function in KO mice. These data demonstrate that a single exposure to acrolein causes cardiac dysfunction through TRPA1 activation and autonomic imbalance characterized by a shift toward parasympathetic modulation. Furthermore, it is clear from the lack of ozone effects that although gaseous irritants are capable of eliciting immediate cardiac changes, gas concentration and properties play important roles. - Highlights: • Acute acrolein exposure causes autonomic imbalance and altered CV function in mice. • TRPA1 mediates acrolein-induced autonomic nervous system cardiac

TRPA1 mediates changes in heart rate variability and cardiac mechanical function in mice exposed to acrolein

International Nuclear Information System (INIS)

Kurhanewicz, Nicole; McIntosh-Kastrinsky, Rachel; Tong, Haiyan; Ledbetter, Allen; Walsh, Leon; Farraj, Aimen; Hazari, Mehdi

2017-01-01

Short-term exposure to ambient air pollution is linked with adverse cardiovascular effects. While previous research focused primarily on particulate matter-induced responses, gaseous air pollutants also contribute to cause short-term cardiovascular effects. Mechanisms underlying such effects have not been adequately described, however the immediate nature of the response suggests involvement of irritant neural activation and downstream autonomic dysfunction. Thus, this study examines the role of TRPA1, an irritant sensory receptor found in the airways, in the cardiac response of mice to acrolein and ozone. Conscious unrestrained wild-type C57BL/6 (WT) and TRPA1 knockout (KO) mice implanted with radiotelemeters were exposed once to 3 ppm acrolein, 0.3 ppm ozone, or filtered air. Heart rate (HR) and electrocardiogram (ECG) were recorded continuously before, during and after exposure. Analysis of ECG morphology, incidence of arrhythmia and heart rate variability (HRV) were performed. Cardiac mechanical function was assessed using a Langendorff perfusion preparation 24 h post-exposure. Acrolein exposure increased HRV independent of HR, as well as incidence of arrhythmia. Acrolein also increased left ventricular developed pressure in WT mice at 24 h post-exposure. Ozone did not produce any changes in cardiac function. Neither gas produced ECG effects, changes in HRV, arrhythmogenesis, or mechanical function in KO mice. These data demonstrate that a single exposure to acrolein causes cardiac dysfunction through TRPA1 activation and autonomic imbalance characterized by a shift toward parasympathetic modulation. Furthermore, it is clear from the lack of ozone effects that although gaseous irritants are capable of eliciting immediate cardiac changes, gas concentration and properties play important roles. - Highlights: • Acute acrolein exposure causes autonomic imbalance and altered CV function in mice. • TRPA1 mediates acrolein-induced autonomic nervous system cardiac

Effect of overreaching on cognitive performance and related cardiac autonomic control.

Science.gov (United States)

Dupuy, O; Lussier, M; Fraser, S; Bherer, L; Audiffren, M; Bosquet, L

2014-02-01

The purpose of this study was to characterize the effect of a 2-week overload period immediately followed by a 1-week taper period on different cognitive processes including executive and nonexecutive functions, and related heart rate variability. Eleven male endurance athletes increased their usual training volume by 100% for 2 weeks, and decreased it by 50% for 1 week. A maximal graded test, a constant speed test at 85% of peak treadmill speed, and a Stroop task with the measurement of heart rate variability were performed at each period. All participants were considered as overreached. We found a moderate increase in the overall reaction time to the three conditions of the Stroop task after the overload period (816 ± 83 vs 892 ± 117 ms, P = 0.03) followed by a return to baseline after the taper period (820 ± 119 ms, P = 0.013). We found no association between cognitive performance and cardiac parasympathetic control at baseline, and no association between changes in these measures. Our findings clearly underscore the relevance of cognitive performance in the monitoring of overreaching in endurance athletes. However, contrary to our hypothesis, we did not find any relationship between executive performance and cardiac parasympathetic control. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Music induces different cardiac autonomic arousal effects in young and older persons.

Science.gov (United States)

Hilz, Max J; Stadler, Peter; Gryc, Thomas; Nath, Juliane; Habib-Romstoeck, Leila; Stemper, Brigitte; Buechner, Susanne; Wong, Samuel; Koehn, Julia

2014-07-01

Autonomic arousal-responses to emotional stimuli change with age. Age-dependent autonomic responses to music-onset are undetermined. To determine whether cardiovascular-autonomic responses to "relaxing" or "aggressive" music differ between young and older healthy listeners. In ten young (22.8±1.7 years) and 10 older volunteers (61.7±7.7 years), we monitored respiration (RESP), RR-intervals (RRI), and systolic and diastolic blood pressure (BPsys, BPdia) during silence and 180second presentations of two "relaxing" and two "aggressive" classical-music excerpts. Between both groups, we compared RESP, RRI, BPs, spectral-powers of mainly sympathetic low-frequency (LF: 0.04-0.15Hz) and parasympathetic high-frequency (HF: 0.15-0.5Hz) RRI-oscillations, RRI-LF/HF-ratios, RRI-total-powers (TP-RRI), and BP-LF-powers during 30s of silence, 30s of music-onset, and the remaining 150s of music presentation (analysis-of-variance and post-hoc analysis; significance: pmusic-onset, "relaxing" music decreased RRI in older and increased BPsys in younger participants, while "aggressive" music decreased RRI and increased BPsys, LF-RRI, LF/HF-ratios, and TP-RRI in older, but increased BPsys and RESP and decreased HF-RRI and TP-RRI in younger participants. Signals did not differ between groups during the last 150s of music presentation. During silence, autonomic modulation was lower - but showed sympathetic predominance - in older than younger persons. Responses to music-onset, particularly "aggressive" music, reflect more of an arousal- than an emotional-response to music valence, with age-specific shifts of sympathetic-parasympathetic balance mediated by parasympathetic withdrawal in younger and by sympathetic activation in older participants. Copyright © 2014 Elsevier B.V. All rights reserved.

Biofeedback on heart rate variability in cardiac rehabilitation: practical feasibility and psycho-physiological effects.

Science.gov (United States)

Climov, Daniela; Lysy, Camille; Berteau, Sylvain; Dutrannois, Jacques; Dereppe, Hubert; Brohet, Christian; Melin, Jacques

2014-06-01

Biofeedback is a self-regulation therapy by which the patient learns how to optimize the functioning of his autonomic nervous system. It has been applied to patients with various cardiovascular disorders. The purpose of this study was to investigate the practical feasibility and the psychophysiological effects of biofeedback applied to heart rate variability (HRV biofeedback) in order to increase cardiac coherence in coronary artery disease (CAD) patients participating in a cardiac rehabilitation programme. In this randomised and controlled study, 31 CAD patients were randomly assigned to an experimental or to a control group. The experimental group participated in a programme of 10 sessions of cardiac coherence biofeedback training, in addition to the rehabilitation programme. The control group participated in the usual cardiac rehabilitation programme only. Physiological variables (systolic and diastolic blood pressure, SDNN) and psychosocial variables (anxiety, depression, type D personality) were measured at the start and at the end of the programme in both groups. Statistical comparisons assessed the inter and intra group differences. The small sample size precludes any firm conclusions concerning the effect of cardiac coherence biofeedback on physiological or psychological variables. However, we observed a significant increase of the percentage of cardiac coherence, in relation with an increased SDNN index. Our study demonstrated the practical feasibility of cardiac coherence biofeedback training in CAD patients. Further research is desirable to investigate the potential benefit of cardiac coherence biofeedback as an adjunct to stress management in cardiac rehabilitation.

Insulin resistance and circadian rhythm of cardiac autonomic modulation

Directory of Open Access Journals (Sweden)

Cai Jianwen

2010-12-01

Full Text Available Abstract Background Insulin resistance (IR has been associated with cardiovascular diseases (CVD. Heart rate variability (HRV, an index of cardiac autonomic modulation (CAM, is also associated with CVD mortality and CVD morbidity. Currently, there are limited data about the impairment of IR on the circadian pattern of CAM. Therefore, we conducted this investigation to exam the association between IR and the circadian oscillations of CAM in a community-dwelling middle-aged sample. Method Homeostasis models of IR (HOMA-IR, insulin, and glucose were used to assess IR. CAM was measured by HRV analysis from a 24-hour electrocardiogram. Two stage modeling was used in the analysis. In stage one, for each individual we fit a cosine periodic model based on the 48 segments of HRV data. We obtained three individual-level cosine parameters that quantity the circadian pattern: mean (M, measures the overall average of a HRV index; amplitude (Â, measures the amplitude of the oscillation of a HRV index; and acrophase time (θ, measures the timing of the highest oscillation. At the second stage, we used a random-effects-meta-analysis to summarize the effects of IR variables on the three circadian parameters of HRV indices obtained in stage one of the analysis. Results In persons without type diabetes, the multivariate adjusted β (SE of log HOMA-IR and M variable for HRV were -0.251 (0.093, -0.245 (0.078, -0.19 (0.06, -4.89 (1.76, -3.35 (1.31, and 2.14 (0.995, for log HF, log LF, log VLF, SDNN, RMSSD and HR, respectively (all P Conclusion Elevated IR, among non-diabetics significantly impairs the overall mean levels of CAM. However, the  or θ of CAM were not significantly affected by IR, suggesting that the circadian mechanisms of CAM are not impaired. However, among persons with type 2 diabetes, a group clinically has more severe form of IR, the adverse effects of increased IR on all three HRV circadian parameters are much larger.

Cardiac autonomic neuropathy in patients with uraemia is not related to pre-diabetes

DEFF Research Database (Denmark)

Eming, Marie Bayer; Hornum, Mads; Feldt-Rasmussen, Bo Friis

2011-01-01

INTRODUCTION: It has been proposed that pre-diabetes may cause neuropathy. The aim of this study was to investigate whether cardiac autonomic neuropathy (CAN) in uraemic patients was related to the presence of pre-diabetes. MATERIAL AND METHODS: The study included 66 non-diabetic uraemic patients...... enrolled. Beat-to-beat variability was determined from the echocardiographic (ECG) recording during deep inspiration and expiration. CAN was defined as a beat-to-beat value below 10 beats/min. Pre-diabetes was defined as presence of impaired fasting glucose and/or impaired glucose tolerance measured...... by oral glucose tolerance test (WHO/American Diabetes Association criteria 2007). RESULTS: The prevalence of CAN was 38% in uraemic patients compared with 8% in the controls (p prediabetic, while the remaining 39 had a normal glucose...

Cardiac sympathetic neuronal imaging using PET

International Nuclear Information System (INIS)

Lautamaeki, Riikka; Tipre, Dnyanesh; Bengel, Frank M.

2007-01-01

Balance of the autonomic nervous system is essential for adequate cardiac performance, and alterations seem to play a key role in the development and progression of various cardiac diseases. PET imaging of the cardiac autonomic nervous system has advanced extensively in recent years, and multiple pre- and postsynaptic tracers have been introduced. The high spatial and temporal resolution of PET enables noninvasive quantification of neurophysiologic processes at the tissue level. Ligands for catecholamine receptors, along with radiolabeled catecholamines and catecholamine analogs, have been applied to determine involvement of sympathetic dysinnervation at different stages of heart diseases such as ischemia, heart failure, and arrhythmia. This review summarizes the recent findings in neurocardiological PET imaging. Experimental studies with several radioligands and clinical findings in cardiac dysautonomias are discussed. (orig.)

Effects of creatine supplementation on cardiac autonomic functions in bodybuilders.

Science.gov (United States)

Mert, Kadir Uğur; Ilgüy, Serdar; Dural, Muhammet; Mert, Gurbet Özge; Özakin, Engin

2017-06-01

Bodybuilder-type workouts may affect heart rate variability (HRV), which has considerable potential to assess the role of autonomic nervous system (ANS). A scientifically designed approach is necessary for bodybuilders to achieve better results while protecting their health. In this study, we aimed to investigate HRV parameters in bodybuilders compared to healthy control subjects and effects of creatine supplementation. A total of 48 male participants (16 controls, 16 supplement (-), 16 supplement (+)) were evaluated in our study. Bodybuilders who were taking creatine supplementation were enrolled in supplement (+) group. HRV parameters were measured from 24-hour Holter recordings of all participants. When mean heart rates were compared with control group (71.5 ± 12.6 beats/min), statistically significant difference was revealed in supplement (-) group (61.8 ± 6.8 beats/min; P = 0.022) unlike supplement (+) group (69.63 ± 14.1 beats/min; P = 0.650). HRV analyses revealed significant parasympathetic shift in supplement (-) group. No significant difference was demonstrated on HRV parameters, except high frequency (P = 0.029) in supplement (+) group. Conclusively, elevated parasympathetic modulation, which is favorable cardiovascular outcome of exercise, was demonstrated in bodybuilders. However, our study also revealed that creatine supplementation attenuates this favorable effect in ANS by limiting elevation of parasympathetic modulation. Although the sympathetic slight shift is attributed to creatine supplementation, it cannot be discriminated from the effects of over training. © 2017 Wiley Periodicals, Inc.

Macrophage populations and cardiac sympathetic denervation during L-NAME-induced hypertension in rats

DEFF Research Database (Denmark)

Neves, S R S; Machado, C R S; Pinto, A M T

2006-01-01

The rat model of hypertension induced by prolonged treatment with Nomega-nitro-L-arginine methyl ester (L-NAME) has been extensively used. However, the effects on cardiac autonomic innervation are unknown. Here, the cardiac sympathetic innervation is analyzed in parallel with myocardial lesions a...

Profound Autonomic Instability Complicated by Multiple Episodes of Cardiac Asystole and Refractory Bradycardia in a Patient with Anti-NMDA Encephalitis

Directory of Open Access Journals (Sweden)

Stephanie R. Mehr

2016-01-01

Full Text Available Anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDARE is autoimmune encephalitis primarily affecting young adults and children. First described about a decade ago, it frequently manifests as a syndrome that includes progressive behavioral changes, psychosis, central hypoventilation, seizures, and autonomic instability. Although cardiac arrhythmias often accompany anti-NMDARE, the need for long-term electrophysiological support is rare. We describe the case of NMDARE whose ICU course was complicated by progressively worsening episodes of tachyarrhythmia-bradyarrhythmia and episodes of asystole from which she was successfully resuscitated. Her life-threatening episodes of autonomic instability were successfully controlled only after the placement of a permanent pacemaker during her ICU stay. She made a clinical recovery and was discharged to a skilled nursing facility after a protracted hospital course.

Study of the association between left ventricular diastolic impairment and cardiac autonomic neuropathy in diabetic patients using [123I] metaiodobenzylguanidine scintigraphy

International Nuclear Information System (INIS)

Suzuki, Rokuro; Tanaka, Shiro; Tojo, Osamu; Ishii, Tomofusa; Sato, Toshihiko; Fujii, Satoru; Tumura, Kei.

1994-01-01

The association between left ventricular (LV) diastolic dysfunction and myocardial MIBG accumulation was investigated. The subjects were 14 Type II diabetic patients who had no evidence of ischemic heat disease, LV hypertrophy or dilated cardiomyopathy as determined by exercise Tl-201 myocardial scintigraphy and echocardiography. In 14 diabetic patients, isovolumic relaxation time (IRT) was measured by M-mode echocardiography, and the subjects were subdivided into two groups: Group1, 8 patients with impaired left ventricular diastolic function (IRT≥80 msec), and Group 2, 6 patients with normal left ventricular diastolic function (IRT 123 I-MIBG myocardial scintigraphy was performed, and the myocardial accumulation of 123 I-MIBG was investigated. The ratio of myocardial to mediastinal MIBG uptake was significantly (p<0.01) lower in Group 1 than in Group 2. And scintigraphic defects were significantly (p<0.05) more numerous in Group 1 than in Group 2. Patients in Group 1 had a greater frequency of cardiac autonomic neuropathy evaluated by QTc interval and coefficient of variation of R-R interval, when compared with Group 2. These data suggest that, in diabetic patients with no evidence of ischemic heart disease, LV hypertrophy or dilated cardiomyopathy, impairment of left ventricular diastolic function is associated with cardiac autonomic neuropathy. (author)

Evaluation of diabetic autonomic neuropathy by 123I-metaiodobenzyl-guanidine (MIBG) cardiac imaging. Initial report

International Nuclear Information System (INIS)

Osonoi, Takeshi; Fukumoto, Yoshihiro; Saitou, Miyoko; Kuroda, Yasuhisa; Uchimi, Nobuo; Ishioka, Kuniharu; Onuma, Tomio; Suga, Shigeki; Takebe, Kazuo.

1994-01-01

Single-photon emission computed tomography was performed in 52 diabetics and 10 healthy volunteers using MIBG. The diabetics had no particular findings of electrocardiography, echocardiography, or exercise thallium imaging and no cardiovascular episodes. The healthy volunteers had no abnormal findings on exercise thallium imaging or glucose tolerance test. The average relative regional uptake (RRU) was decreased in the inferoposterior wall compared with the anterior or lateral wall in both the diabetics and volunteers. According to the RRU and visual images, we divided the diabetics into the following four groups: 14 who were normal (group N), 30 with segmental defects (group S), 4 with diffuse defects (group D) and 4 without accumulation (group DH). Diabetic complications (retinopathy, nephropathy, and neuropathy) and hypertension were more frequent in group S than group N. However, there were no significant differences in the physiological evidence of autonomic neuropathy (C.V. of the R-R interval on the ECG and blood pressure response to standing or deep breathing) between groups S and N. Vibration sense was significantly more impaired in group S than in group N. These results suggest that cardiac imaging with MIBG might be a useful examination for the early diagnosis of diabetic autonomic neuropathy. (author)

Cardiac Organ Damage and Arterial Stiffness in Autonomic Failure: Comparison With Essential Hypertension.

Science.gov (United States)

Milazzo, Valeria; Maule, Simona; Di Stefano, Cristina; Tosello, Francesco; Totaro, Silvia; Veglio, Franco; Milan, Alberto

2015-12-01

Autonomic failure (AF) is characterized by orthostatic hypotension, supine hypertension, and increased blood pressure (BP) variability. AF patients develop cardiac organ damage, similarly to essential hypertension (EH), and have higher arterial stiffness than healthy controls. Determinants of cardiovascular organ damage in AF are not well known: both BP variability and mean BP values may be involved. The aim of the study was to evaluate cardiac organ damage, arterial stiffness, and central hemodynamics in AF, compared with EH subjects with similar 24-hour BP and a group of healthy controls, and to evaluate determinants of target organ damage in patients with AF. Twenty-seven patients with primary AF were studied (mean age, 65.7±11.2 years) using transthoracic echocardiography, carotid-femoral pulse wave velocity, central hemodynamics, and 24-hour ambulatory BP monitoring. They were compared with 27 EH subjects matched for age, sex, and 24-hour mean BP and with 27 healthy controls. AF and EH had similar left ventricular mass (101.6±33.3 versus 97.7±28.1 g/m(2), P=0.59) and carotid-femoral pulse wave velocity (9.3±1.8 versus 9.2±3.0 m/s, P=0.93); both parameters were significantly lower in healthy controls (Phypertensive heart disease and increased arterial stiffness, similar to EH with comparable mean BP values. Twenty-four-hour and nighttime systolic BP were determinants of cardiovascular damage, independent of BP variability. © 2015 American Heart Association, Inc.

Transcutaneous cervical vagal nerve stimulation modulates cardiac vagal tone and tumor necrosis factor-alpha

DEFF Research Database (Denmark)

Brock, C; Brock, B; Aziz, Q

2017-01-01

-VNS, there was an increase in cardiac vagal tone and a reduction in tumor necrosis factor-α in comparison to baseline. No change was seen in blood pressure, cardiac sympathetic index or other cytokines. These preliminary data suggest that t-VNS exerts an autonomic and a subtle antitumor necrosis factor-α effect, which...

Cardiac Autonomic Responses during Exercise and Post-exercise Recovery Using Heart Rate Variability and Systolic Time Intervals—A Review

Science.gov (United States)

Michael, Scott; Graham, Kenneth S.; Davis, Glen M.

2017-01-01

Cardiac parasympathetic activity may be non-invasively investigated using heart rate variability (HRV), although HRV is not widely accepted to reflect sympathetic activity. Instead, cardiac sympathetic activity may be investigated using systolic time intervals (STI), such as the pre-ejection period. Although these autonomic indices are typically measured during rest, the “reactivity hypothesis” suggests that investigating responses to a stressor (e.g., exercise) may be a valuable monitoring approach in clinical and high-performance settings. However, when interpreting these indices it is important to consider how the exercise dose itself (i.e., intensity, duration, and modality) may influence the response. Therefore, the purpose of this investigation was to review the literature regarding how the exercise dosage influences these autonomic indices during exercise and acute post-exercise recovery. There are substantial methodological variations throughout the literature regarding HRV responses to exercise, in terms of exercise protocols and HRV analysis techniques. Exercise intensity is the primary factor influencing HRV, with a greater intensity eliciting a lower HRV during exercise up to moderate-high intensity, with minimal change observed as intensity is increased further. Post-exercise, a greater preceding intensity is associated with a slower HRV recovery, although the dose-response remains unclear. A longer exercise duration has been reported to elicit a lower HRV only during low-moderate intensity and when accompanied by cardiovascular drift, while a small number of studies have reported conflicting results regarding whether a longer duration delays HRV recovery. “Modality” has been defined multiple ways, with limited evidence suggesting exercise of a greater muscle mass and/or energy expenditure may delay HRV recovery. STI responses during exercise and recovery have seldom been reported, although limited data suggests that intensity is a key

Central nervous system involvement in the autonomic responses to psychological distress

NARCIS (Netherlands)

de Morree, H.M.; Szabó, B.M.; Rutten, G.J.; Kop, W.J.

2013-01-01

Psychological distress can trigger acute coronary syndromes and sudden cardiac death in vulnerable patients. The primary pathophysiological mechanism that plays a role in stress-induced cardiac events involves the autonomic nervous system, particularly disproportional sympathetic activation and

High-frequency autonomic modulation: a new model for analysis of autonomic cardiac control.

Science.gov (United States)

Champéroux, Pascal; Fesler, Pierre; Judé, Sebastien; Richard, Serge; Le Guennec, Jean-Yves; Thireau, Jérôme

2018-05-03

Increase in high-frequency beat-to-beat heart rate oscillations by torsadogenic hERG blockers appears to be associated with signs of parasympathetic and sympathetic co-activation which cannot be assessed directly using classic methods of heart rate variability analysis. The present work aimed to find a translational model that would allow this particular state of the autonomic control of heart rate to be assessed. High-frequency heart rate and heart period oscillations were analysed within discrete 10 s intervals in a cohort of 200 healthy human subjects. Results were compared to data collected in non-human primates and beagle dogs during pharmacological challenges and torsadogenic hERG blockers exposure, in 127 genotyped LQT1 patients on/off β-blocker treatment and in subgroups of smoking and non-smoking subjects. Three states of autonomic modulation, S1 (parasympathetic predominance) to S3 (reciprocal parasympathetic withdrawal/sympathetic activation), were differentiated to build a new model of heart rate variability referred to as high-frequency autonomic modulation. The S2 state corresponded to a specific state during which both parasympathetic and sympathetic systems were coexisting or co-activated. S2 oscillations were proportionally increased by torsadogenic hERG-blocking drugs, whereas smoking caused an increase in S3 oscillations. The combined analysis of the magnitude of high-frequency heart rate and high-frequency heart period oscillations allows a refined assessment of heart rate autonomic modulation applicable to long-term ECG recordings and offers new approaches to assessment of the risk of sudden death both in terms of underlying mechanisms and sensitivity. © 2018 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

The ECG Vertigo in Diabetes and Cardiac Autonomic Neuropathy

OpenAIRE

Voulgari, Christina; Tentolouris, Nicholas; Stefanadis, Christodoulos

2011-01-01

The importance of diabetes in the epidemiology of cardiovascular diseases cannot be overemphasized. About one third of acute myocardial infarction patients have diabetes, and its prevalence is steadily increasing. The decrease in cardiac mortality in people with diabetes is lagging behind that of the general population. Cardiovascular disease is a broad term which includes any condition causing pathological changes in blood vessels, cardiac muscle or valves, and cardiac rhythm. The ECG offers...

Cardiovascular autonomic function in Cushing's syndrome.

Science.gov (United States)

Fallo, F; Maffei, P; Dalla Pozza, A; Carli, M; Della Mea, P; Lupia, M; Rabbia, F; Sonino, N

2009-01-01

Cardiac autonomic dysfunction is associated with increased cardiovascular mortality. No data on sympathovagal balance are available in patients with Cushing's syndrome, in whom cardiovascular risk is high. We studied 10 patients with newly diagnosed Cushing's syndrome (1 male/9 females; age mean+/-SD, 47+/-10 yr) and 10 control subjects matched for age, sex, body mass index, and cardiovascular risk factors. In both groups there were 7 patients with arterial hypertension, 3 with diabetes mellitus, and 2 with obesity. Cardiac autonomic function was evaluated by analysis of short time heart rate variability (HRV) measures in frequency domain over 24-h, daytime, and nighttime. The 24-h ambulatory blood pressure monitoring and echocardiography were also performed. In comparison with controls, patients with Cushing's syndrome had lower 24-h (1.3+/-0.6 vs 3.7+/-1.5, mean+/-SD, p<0.01), daytime (2.0+/-1.4 vs 4.5+/-1.6, p<0.01), and night-time (1.0+/-0.4 vs 3.5+/-2.3, p<0.01) low-frequency/ high frequency (LF/HF) power ratio. In the presence of similar LF power, the difference was due to elevation in HF power in Cushing's syndrome compared to controls: 24-h, 12.7+/-6.7 vs 5.8+/-2.8, p<0.01; daytime, 10.2+/-7.3 vs 4.5+/-2.1, p<0.05; nighttime, 14.2+/-7.0 vs 7.8+/-4.7, p<0.05. Eight Cushing patients vs 4 controls had a non-dipping blood pressure profile. At echocardiography, Cushing patients had a greater left ventricular mass index and/or relative wall thickness, and impaired diastolic function, compared with controls. Compared to controls, patients with Cushing's syndrome showed a sympathovagal imbalance, characterized by a relatively increased parasympathetic activity. Whether this autonomic alteration is meant to counterbalance cortisol-induced effects on blood pressure and cardiac structure/function or has a different pathophysiological significance is still unknown.

Autonomic hyper-vigilance in post-infective fatigue syndrome.

Science.gov (United States)

Kadota, Yumiko; Cooper, Gavin; Burton, Alexander R; Lemon, Jim; Schall, Ulrich; Lloyd, Andrew; Vollmer-Conna, Ute

2010-09-01

This study examined whether post-infective fatigue syndrome (PIFS) is associated with a disturbance in bidirectional autonomic signalling resulting in heightened perception of symptoms and sensations from the body in conjunction with autonomic hyper-reactivity to perceived challenges. We studied 23 patients with PIFS and 25 healthy matched control subjects. A heartbeat discrimination task and a pressure pain threshold test were used to assess interoceptive sensitivity. Cardiac response was assessed over a 4-min Stroop task. PIFS was associated with higher accuracy in heartbeat discrimination and a lower pressure pain threshold. Increased interoceptive sensitivity correlated strongly with current symptoms and potentiated differences in the cardiac response to the Stroop task, which in PIFS was characterized by insensitivity to task difficulty and lack of habituation. Our results provide the first evidence of heightened interoceptive sensitivity in PIFS. Together with the distinct pattern in cardiac responsivity these findings present a picture of physiological hyper-vigilance and response inflexibility. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Zebrafish heart as a model to study the integrative autonomic control of pacemaker function

Science.gov (United States)

Stoyek, Matthew R.; Quinn, T. Alexander; Croll, Roger P.

2016-01-01

The cardiac pacemaker sets the heart's primary rate, with pacemaker discharge controlled by the autonomic nervous system through intracardiac ganglia. A fundamental issue in understanding the relationship between neural activity and cardiac chronotropy is the identification of neuronal populations that control pacemaker cells. To date, most studies of neurocardiac control have been done in mammalian species, where neurons are embedded in and distributed throughout the heart, so they are largely inaccessible for whole-organ, integrative studies. Here, we establish the isolated, innervated zebrafish heart as a novel alternative model for studies of autonomic control of heart rate. Stimulation of individual cardiac vagosympathetic nerve trunks evoked bradycardia (parasympathetic activation) and tachycardia (sympathetic activation). Simultaneous stimulation of both vagosympathetic nerve trunks evoked a summative effect. Effects of nerve stimulation were mimicked by direct application of cholinergic and adrenergic agents. Optical mapping of electrical activity confirmed the sinoatrial region as the site of origin of normal pacemaker activity and identified a secondary pacemaker in the atrioventricular region. Strong vagosympathetic nerve stimulation resulted in a shift in the origin of initial excitation from the sinoatrial pacemaker to the atrioventricular pacemaker. Putative pacemaker cells in the sinoatrial and atrioventricular regions expressed adrenergic β2 and cholinergic muscarinic type 2 receptors. Collectively, we have demonstrated that the zebrafish heart contains the accepted hallmarks of vertebrate cardiac control, establishing this preparation as a viable model for studies of integrative physiological control of cardiac function by intracardiac neurons. PMID:27342878

Improvements in Attention and Cardiac Autonomic Modulation After a 2-Weeks Sprint Interval Training Program: A Fidelity Approach

Directory of Open Access Journals (Sweden)

Arilson F. M. de Sousa

2018-03-01

Full Text Available This study aimed to: (1 investigate the influence of a 2-weeks sprint interval training (SIT program on aerobic capacity, cardiac autonomic control, and components of attention in young healthy university students; and (2 to ascertain whether training fidelity would influence these adaptations. One hundred and nine participants were divided into an experimental (EG and control (CG groups. The EG performed a SIT program that consisted of 6 sessions of 4 × 30 s “all-out” efforts on a cycle ergometer, interspersed with active rests of 4 min. The criterion for fidelity was achieving >90% of estimated maximum heart rate (HR during sprint bouts. After analyses, the EG was divided into HIGH (n = 26 and LOW (n = 46 fidelity groups. Components of attention were assessed using the Attention Network Test (ANT. Aerobic capacity (VO2max was estimated while the sum of skinfolds was determined. Autonomic control of HR was assessed by means of HR variability (HRV and HR complexity at rest and during ANT. Both HIGH and LOW significantly increased aerobic capacity, vagal modulation before and during ANT, and executive control, and decreased body fatness after SIT (p < 0.05. However, only participants from HIGH showed an increase in HR complexity and accuracy in ANT when compared to LOW (p < 0.05. Two weeks of SIT improved executive control, body fatness, aerobic fitness, and autonomic control in university students with better results reported in those individuals who exhibited high fidelity.

Macaque cardiac physiology is sensitive to the valence of passively viewed sensory stimuli.

Directory of Open Access Journals (Sweden)

Eliza Bliss-Moreau

Full Text Available Autonomic nervous system activity is an important component of affective experience. We demonstrate in the rhesus monkey that both the sympathetic and parasympathetic branches of the autonomic nervous system respond differentially to the affective valence of passively viewed video stimuli. We recorded cardiac impedance and an electrocardiogram while adult macaques watched a series of 300 30-second videos that varied in their affective content. We found that sympathetic activity (as measured by cardiac pre-ejection period increased and parasympathetic activity (as measured by respiratory sinus arrhythmia decreased as video content changes from positive to negative. These findings parallel the relationship between autonomic nervous system responsivity and valence of stimuli in humans. Given the relationship between human cardiac physiology and affective processing, these findings suggest that macaque cardiac physiology may be an index of affect in nonverbal animals.

Hypothalamic-pituitary-adrenal and cardiac autonomic responses to transrectal examination differ with behavioral reactivity in dairy cows.

Science.gov (United States)

Kovács, L; Kézér, F L; Kulcsár-Huszenicza, M; Ruff, F; Szenci, O; Jurkovich, V

2016-09-01

Behavior, hypothalamic-pituitary-adrenal axis, and cardiac autonomic nervous system (ANS) activity were evaluated in response to transrectal examination in nonlactating Holstein-Friesian cows with different behavioral reactivity. According to behavioral reactions shown to the procedure of fixing the heart rate (HR) monitors, the 20 cows with the highest and the 20 cows with the lowest behavioral reactivity were involved in the study (high responder, n=20; and low responder, n=20, respectively). Activity of the ANS was assessed by HR and HR variability parameters. Blood and saliva were collected at 5 min before (baseline) and 0, 5 10, 15, 20, 30, 40, 60, and 120 min after the examination to determine cortisol concentrations. The examination lasted for 5 min. Cardiac parameters included HR, the root mean square of successive differences between the consecutive interbeat intervals, the high frequency (HF) component of heart rate variability, and the ratio between the low frequency (LF) and HF parameter (LF/HF). Following the examination, peak plasma and saliva cortisol levels and the amplitude of the plasma and saliva cortisol response were higher in high responder cows than in low responders. Areas under the plasma and saliva cortisol response curves were greater in high responder cows. Plasma and salivary cortisol levels correlated significantly at baseline (r=0.91), right after examination (r=0.98), and at peak levels (r=0.96). Area under the HR response curve was higher in low responder cows; however, maximum HR and the amplitude of the HR response showed no differences between groups. Minimum values of both parameters calculated for the examination were higher in high responders. Following the examination, response parameters of root mean square of successive differences and HF did not differ between groups. The maximum and the amplitude of LF/HF response and area under the LF/HF response curve were lower in low responder cows, suggesting a lower sympathetic

High-Intensity Progressive Resistance Training Increases Strength With No Change in Cardiovascular Function and Autonomic Neural Regulation in Older Adults.

Science.gov (United States)

Kanegusuku, Hélcio; Queiroz, Andréia C; Silva, Valdo J; de Mello, Marco T; Ugrinowitsch, Carlos; Forjaz, Cláudia L

2015-07-01

The effects of high-intensity progressive resistance training (HIPRT) on cardiovascular function and autonomic neural regulation in older adults are unclear. To investigate this issue, 25 older adults were randomly divided into two groups: control (CON, N = 13, 63 ± 4 years; no training) and HIPRT (N = 12, 64 ± 4 years; 2 sessions/week, 7 exercises, 2–4 sets, 10–4 RM). Before and after four months, maximal strength, quadriceps cross-sectional area (QCSA), clinic and ambulatory blood pressures (BP), systemic hemodynamics, and cardiovascular autonomic modulation were measured. Maximal strength and QCSA increased in the HIPRT group and did not change in the CON group. Clinic and ambulatory BP, cardiac output, systemic vascular resistance, stroke volume, heart rate, and cardiac sympathovagal balance did not change in the HIPRT group or the CON group. In conclusion, HIPRT was effective at increasing muscle mass and strength without promoting changes in cardiovascular function or autonomic neural regulation.

Arg16Gly and Gln27Glu β2 adrenergic polymorphisms influence cardiac autonomic modulation and baroreflex sensitivity in healthy young Brazilians

Science.gov (United States)

Atala, Magda M; Goulart, Alessandra; Guerra, Grazia M; Mostarda, Cristiano; Rodrigues, Bruno; Mello, Priscila R; Casarine, Dulce E; Irigoyen, Maria-Claudia; Pereira, Alexandre C; Consolim-Colombo, Fernanda M

2015-01-01

The association between functional β2 adrenergic receptor (β2-AR) polymorphisms and cardiac autonomic modulation is still unclear. Thus, two common polymorphisms in the β2-AR gene (Gln27Glu β2 and Arg16Gly β2) were studied to determine whether they might affect tonic and reflex cardiac sympathetic activity in healthy young subjects. A total of 213 healthy young white subjects of both genders (53% female), aged 18-30 years (23.5±3.4 y), had their continuous blood pressure curves noninvasively recorded by Finometer at baseline, and other hemodynamic parameters, as cardiac autonomic modulation, baroreflex sensitivity, and allele, genotype, and diplotype frequencies calculated. Associations were made between Arg16Gly β2 and Gln27Glu β2 polymorphisms and between β2-AR diplotypes and all variables. The heart rate was significantly lower (P<0.001) in the presence of homozygous Arg/Arg alleles (60.9±1.5 bpm) than in that of Arg/Gly heterozygotes (65.9±1.0 bpm) or Gly/Gly homozygotes (66.3±1.2 bpm). Homozygous carriers of Arg16 allele had an alpha index (19.2±1.3) significantly higher (P<0.001) than that of the subjects with the Gly allele Gly/Gly (14.5±0.7) or Arg/Gly (14.6±0.7). Furthermore, the recessive Glu27Glu and the heterozygous Gln27Glu genotypes had a higher percentage of low-frequency components (LF%) than the homozygous Gln27Gln (15.1% vs. 16.0% vs. 8.2%, P=0.03, respectively). In healthy young subjects, the presence of β2-AR Arg16 allele in a recessive model was associated with higher baroreflex sensitivity, and increased parasympathetic modulation in studied individuals. PMID:25755837

Autonomic innervation of the heart. Role of molecular imaging

Energy Technology Data Exchange (ETDEWEB)

Slart, Riemer H.J.A; Elsinga, Philip H. [Univ. Medical Center Groningen (Netherlands). Nuclear Medicine and Molecular Imaging; Tio, Rene A. [Univ. Medical Center Groningen (Netherlands). Thorax Center Cardiology; Schwaiger, Markus (ed.) [Technische Univ. Muenchen Klinikum Rechts der Isar (Germany). Nuklearmedizinische Klinik

2015-03-01

Reviews in detail the value of SPECT-CT and PET-CT in the imaging of cardiac innervation. Details the role of imaging in a range of conditions and diseases. Includes important background on pathophysiology, tracers, radiopharmaceutical production, and kinetic modeling software. This book explains in detail the potential value of the hybrid modalities, SPECT-CT and PET-CT, in the imaging of cardiac innervation in a wide range of conditions and diseases, including ischemic heart disease, diabetes mellitus, heart failure, amyloidosis, heart transplantation, and ventricular arrhythmias. Imaging of the brain-heart axis in neurodegenerative disease and stress and of cardiotoxicity is also discussed. The roles of the various available tracers are fully considered, and individual chapters address radiopharmaceutical development under GMP, imaging physics, and kinetic modeling software. Highly relevant background information is included on the autonomic nervous system of the heart and its pathophysiology, and in addition future perspectives are discussed. Awareness of the importance of autonomic innervation of the heart for the optimal management of cardiac patients is growing, and there is an evident need for objective measurement techniques or imaging modalities. In this context, Autonomic Innervation of the Heart will be of wide interest to clinicians, researchers, and industry.

Autonomic innervation of the heart. Role of molecular imaging

International Nuclear Information System (INIS)

Slart, Riemer H.J.A; Elsinga, Philip H.; Tio, Rene A.; Schwaiger, Markus

2015-01-01

Reviews in detail the value of SPECT-CT and PET-CT in the imaging of cardiac innervation. Details the role of imaging in a range of conditions and diseases. Includes important background on pathophysiology, tracers, radiopharmaceutical production, and kinetic modeling software. This book explains in detail the potential value of the hybrid modalities, SPECT-CT and PET-CT, in the imaging of cardiac innervation in a wide range of conditions and diseases, including ischemic heart disease, diabetes mellitus, heart failure, amyloidosis, heart transplantation, and ventricular arrhythmias. Imaging of the brain-heart axis in neurodegenerative disease and stress and of cardiotoxicity is also discussed. The roles of the various available tracers are fully considered, and individual chapters address radiopharmaceutical development under GMP, imaging physics, and kinetic modeling software. Highly relevant background information is included on the autonomic nervous system of the heart and its pathophysiology, and in addition future perspectives are discussed. Awareness of the importance of autonomic innervation of the heart for the optimal management of cardiac patients is growing, and there is an evident need for objective measurement techniques or imaging modalities. In this context, Autonomic Innervation of the Heart will be of wide interest to clinicians, researchers, and industry.

Distinctive cardiac autonomic dysfunction following stress exposure in both sexes in an animal model of PTSD.

Science.gov (United States)

Koresh, Ori; Kaplan, Zeev; Zohar, Joseph; Matar, Michael A; Geva, Amir B; Cohen, Hagit

2016-07-15

It is unclear whether the poor autonomic flexibility or dysregulation observed in patients with posttraumatic stress disorder (PTSD) represents a pre-trauma vulnerability factor or results from exposure to trauma. We used an animal model of PTSD to assess the association between the behavioral response to predator scent stress (PSS) and the cardiac autonomic modulation in male and female rats. The rats were surgically implanted with radiotelemetry devices to measure their electrocardiograms and locomotor activity (LMA). Following baseline telemetric monitoring, the animals were exposed to PSS or sham-PSS. Continuous telemetric monitoring (24h/day sampling) was performed over the course of 7days. The electrocardiographic recordings were analyzed using the time- and frequency-domain indexes of heart rate variability (HRV). The behavioral response patterns were assessed using the elevated plus maze and acoustic startle response paradigms for the retrospective classification of individuals according to the PTSD-related cut-off behavioral criteria. During resting conditions, the male rats had significantly higher heart rates (HR) and lower HRV parameters than the female rats during both the active and inactive phases of the daily cycle. Immediately after PSS exposure, both the female and male rats demonstrated a robust increase in HR and a marked drop in HRV parameters, with a shift of sympathovagal balance towards sympathetic predominance. In both sexes, autonomic system habituation and recovery were selectively inhibited in the rats whose behavior was extremely disrupted after exposure to PSS. However, in the female rats, exposure to the PSS produced fewer EBR rats, with a more rapid recovery curve than that of the male rats. PSS did not induce changes to the circadian rhythm of the LMA. According to our results, PTSD can be conceptualized as a disorder that is related to failure-of-recovery mechanisms that impede the restitution of physiological homeostasis

Are Cardiac Autonomic Nervous System Activity and Perceived Stress Related to Functional Somatic Symptoms in Adolescents? The TRAILS Study.

Directory of Open Access Journals (Sweden)

Karin A M Janssens

Full Text Available Stressors have been related to medically insufficiently explained or functional somatic symptoms (FSS. However, the underlying mechanism of this association is largely unclear. In the current study, we examined whether FSS are associated with different perceived stress and cardiac autonomic nervous system (ANS levels during a standardized stressful situation, and whether these associations are symptom-specific.We examined 715 adolescents (16.1 years, 51.3% girls from the Dutch cohort study Tracking Adolescents' Individual Lives Sample during the Groningen Social Stress Test (GSST. FSS were assessed by the Youth Self-Report, and clustered into a cluster of overtiredness, dizziness and musculoskeletal pain and a cluster of headache and gastrointestinal symptoms. Perceived stress levels (i.e. unpleasantness and arousal were assessed by the Self-Assessment Manikin, and cardiac ANS activity by assessing heart rate variability (HRV-HF and pre-ejection period (PEP. Perceived stress and cardiac ANS levels before, during, and after the GSST were studied as well as cardiac ANS reactivity. Linear regression analyses were used to examine the associations.Perceived arousal levels during (beta = 0.09, p = 0.04 and after (beta = 0.07, p = 0.047 the GSST, and perceived unpleasantness levels before (beta = 0.07, p = 0.048 and during (beta = 0.12, p = 0.001 the GSST were related to FSS during the past couple of months. The association between perceived stress and FSS was stronger for the FSS cluster of overtiredness, dizziness and musculoskeletal pain than for the cluster of headache and gastrointestinal symptoms. Neither ANS activity levels before, during, and after the GSST, nor maximal HF-HRV and PEP reactivity were related to FSS.This study suggests that perceived stress levels during social stress are related to FSS, whereas cardiac ANS activity and reactivity are not related to FSS.

Cardiac parasympathetic reactivation following exercise: implications for training prescription.

Science.gov (United States)

Stanley, Jamie; Peake, Jonathan M; Buchheit, Martin

2013-12-01

The objective of exercise training is to initiate desirable physiological adaptations that ultimately enhance physical work capacity. Optimal training prescription requires an individualized approach, with an appropriate balance of training stimulus and recovery and optimal periodization. Recovery from exercise involves integrated physiological responses. The cardiovascular system plays a fundamental role in facilitating many of these responses, including thermoregulation and delivery/removal of nutrients and waste products. As a marker of cardiovascular recovery, cardiac parasympathetic reactivation following a training session is highly individualized. It appears to parallel the acute/intermediate recovery of the thermoregulatory and vascular systems, as described by the supercompensation theory. The physiological mechanisms underlying cardiac parasympathetic reactivation are not completely understood. However, changes in cardiac autonomic activity may provide a proxy measure of the changes in autonomic input into organs and (by default) the blood flow requirements to restore homeostasis. Metaboreflex stimulation (e.g. muscle and blood acidosis) is likely a key determinant of parasympathetic reactivation in the short term (0-90 min post-exercise), whereas baroreflex stimulation (e.g. exercise-induced changes in plasma volume) probably mediates parasympathetic reactivation in the intermediate term (1-48 h post-exercise). Cardiac parasympathetic reactivation does not appear to coincide with the recovery of all physiological systems (e.g. energy stores or the neuromuscular system). However, this may reflect the limited data currently available on parasympathetic reactivation following strength/resistance-based exercise of variable intensity. In this review, we quantitatively analyse post-exercise cardiac parasympathetic reactivation in athletes and healthy individuals following aerobic exercise, with respect to exercise intensity and duration, and fitness

Alterations in cardiac autonomic control in spinal cord injury

DEFF Research Database (Denmark)

Biering-Sørensen, Fin; Biering-Sørensen, Tor; Liu, Nan

2018-01-01

parasympathetic cardiac control. Decreases in sympathetic activity result in heart rate and the arterial blood pressure changes, and may cause arrhythmias, in particular bradycardia, with the risk of cardiac arrest in those with cervical or high thoracic injuries. The objective of this review is to give an update...

Cardiac autonomic functions and the emergence of violence in a highly realistic model of social conflict in humans.

Directory of Open Access Journals (Sweden)

Jozsef eHaller

2014-10-01

Full Text Available Among the multitude of factors that can transform human social interactions into violent conflicts, biological features received much attention in recent years as correlates of decision making and aggressiveness especially in critical situations. We present here a highly realistic new model of human aggression and violence, where genuine acts of aggression are readily performed and which at the same time allows the parallel recording of biological concomitants. Particularly, we studied police officers trained at the International Training Centre (Budapest, Hungary, who are prepared to perform operations under extreme conditions of stress. We found that aggressive arousal can transform a basically peaceful social encounter into a violent conflict. Autonomic recordings show that this change is accompanied by increased heart rates, which was associated earlier with reduced cognitive complexity of perceptions (attentional myopia and promotes a bias towards hostile attributions and aggression. We also observed reduced heart rate variability in violent subjects, which is believed to signal a poor functioning of prefrontal-subcortical inhibitory circuits and reduces self-control. Importantly, these autonomic particularities were observed already at the beginning of social encounters i.e. before aggressive acts were initiated, suggesting that individual characteristics of the stress-response define the way in which social pressure affects social behavior, particularly the way in which this develops into violence. Taken together, these findings suggest that cardiac autonomic functions are valuable external symptoms of internal motivational states and decision making processes, and raise the possibility that behavior under social pressure can be predicted by the individual characteristics of stress responsiveness.

Characterization of Glutamatergic Neurons in the Rat Atrial Intrinsic Cardiac Ganglia that Project to the Cardiac Ventricular Wall

Science.gov (United States)

Wang, Ting; Miller, Kenneth E.

2016-01-01

The intrinsic cardiac nervous system modulates cardiac function by acting as an integration site for regulating autonomic efferent cardiac output. This intrinsic system is proposed to be composed of a short cardio-cardiac feedback control loop within the cardiac innervation hierarchy. For example, electrophysiological studies have postulated the presence of sensory neurons in intrinsic cardiac ganglia for regional cardiac control. There is still a knowledge gap, however, about the anatomical location and neurochemical phenotype of sensory neurons inside intrinsic cardiac ganglia. In the present study, rat intrinsic cardiac ganglia neurons were characterized neurochemically with immunohistochemistry using glutamatergic markers: vesicular glutamate transporters 1 and 2 (VGLUT1; VGLUT2), and glutaminase (GLS), the enzyme essential for glutamate production. Glutamatergic neurons (VGLUT1/VGLUT2/GLS) in the ICG that have axons to the ventricles were identified by retrograde tracing of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) injected in the ventricular wall. Co-labeling of VGLUT1, VGLUT2, and GLS with the vesicular acetylcholine transporter (VAChT) was used to evaluate the relationship between post-ganglionic autonomic neurons and glutamatergic neurons. Sequential labeling of VGLUT1 and VGLUT2 in adjacent tissue sections was used to evaluate the co-localization of VGLUT1 and VGLUT2 in ICG neurons. Our studies yielded the following results: (1) intrinsic cardiac ganglia contain glutamatergic neurons with GLS for glutamate production and VGLUT1 and 2 for transport of glutamate into synaptic vesicles; (2) atrial intrinsic cardiac ganglia contain neurons that project to ventricle walls and these neurons are glutamatergic; (3) many glutamatergic ICG neurons also were cholinergic, expressing VAChT. (4) VGLUT1 and VGLUT2 co-localization occurred in ICG neurons with variation of their protein expression level. Investigation of both glutamatergic and cholinergic ICG

Assessment of cardiac sympathetic nerve integrity with positron emission tomography

International Nuclear Information System (INIS)

Raffel, David M.; Wieland, Donald M.

2001-01-01

The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. This paper reviews the development of neuronal imaging agents and discusses their emerging role in the noninvasive assessment of cardiac sympathetic innervation

Autonomic Modulation in Duchenne Muscular Dystrophy during a Computer Task: A Prospective Control Trial.

Directory of Open Access Journals (Sweden)

Mayra Priscila Boscolo Alvarez

Full Text Available Duchenne Muscular Dystrophy (DMD is characterized by progressive muscle weakness that can lead to disability. Owing to functional difficulties faced by individuals with DMD, the use of assistive technology is essential to provide or facilitate functional abilities. In DMD, cardiac autonomic dysfunction has been reported in addition to musculoskeletal impairment. Consequently, the objective was to investigate acute cardiac autonomic responses, by Heart Rate Variability (HRV, during computer tasks in subjects with DMD.HRV was assessed by linear and nonlinear methods, using the heart rate monitor Polar RS800CX chest strap Electrocardiographic measuring device. Then, 45 subjects were included in the group with DMD and 45 in the healthy Typical Development (TD control group. They were assessed for twenty minutes at rest sitting, and five minutes after undergoing a task on the computer.Individuals with DMD had a statistically significant lower parasympathetic cardiac modulation at rest when compared to the control group, which further declined when undergoing the tasks on the computer.DMD patients presented decreased HRV and exhibited greater intensity of cardiac autonomic responses during computer tasks characterized by vagal withdrawal when compared to the healthy TD control subjects.

Is applying the same exercise-based inpatient program to normal and reduced left ventricular function patients the best strategy after coronary surgery? A focus on autonomic cardiac response.

Science.gov (United States)

Mendes, Renata Gonçalves; Simões, Rodrigo Polaquini; Costa, Fernando de Souza Melo; Pantoni, Camila Bianca Falasco; Di Thommazo-Luporini, Luciana; Luzzi, Sérgio; Amaral-Neto, Othon; Arena, Ross; Catai, Aparecida Maria; Borghi-Silva, Audrey

2014-01-01

To assess whether the same exercise-based inpatient program applied to patients with normal and reduced left ventricular function (LVF) evokes a similar cardiac autonomic response after coronary artery bypass graft (CABG). Forty-four patients post-CABG, subgrouped according to normal LVF [LVFN: n = 23; left ventricular ejection fraction (LVEF) ≥ 55%] and reduced LVF (LVFR: n = 21; LVEF 35-54%), were included. All initiated the exercise protocol on post-operative day 1 (PO1), following a whole progressive program until discharge. Cardiac autonomic response was assessed by the indices of heart rate variability (HRV) at rest and during exercise (extremity range of motion and ambulation). During ambulation, lower values of HRV indices were found in the LVFR group compared with the LVFN group [standard deviation of all RR (STDRR; 6.1 ± 2.7 versus 8.9 ± 4.7 ms), baseline width of the RR histogram (TINN; 30.6 ± 14.8 versus 45.8 ± 24.9 ms), SD2 (14.8 ± 8.0 versus 21.3 ± 9.0 ms), Shannon entropy (3.6 ± 0.5 versus 3.9 ± 0.4) and correlation dimension (0.08 ± 0.2 versus 0.2 ± 0.2)]. Also, when comparing the ambulation to rest change, lower values were observed in the LVFR group for linear (STDRR, TINN, RR TRI, rMSSD) and non-linear (SD2 and correlation dimension) HRV indices (p exercise (extremity range of motion), for mean intervals between heart beats and heart rate. For patients with LVFN, the same inpatient exercise protocol triggered a more attenuated autonomic response compared with patients with LVFR. These findings have implications as to how exercise should be prescribed according to LVF in the early stages following recovery from CABG. Implications for Rehabilitation Exercise-based inpatient program, performed by post-CABG patients who have normal left ventricular function, triggered a more attenuated cardiac autonomic response compared with patients with reduced left ventricular function. Volume of the inpatient exercises should be prescribed according

Association of evening smartphone use with cardiac autonomic nervous activity after awakening in adolescents living in high school dormitories.

Science.gov (United States)

Nose, Yoko; Fujinaga, Rina; Suzuki, Maki; Hayashi, Ikuyo; Moritani, Toshio; Kotani, Kazuhiko; Nagai, Narumi

2017-04-01

Smartphones are prevalently used among adolescents; however, nighttime exposure to blue-enriched light, through electric devices, is known to induce delays of the circadian rhythm phases and poor morning somatic conditions. We therefore investigated whether evening smartphone use may affect sleep-wake cycle and cardiac autonomic nervous system (ANS) activity after awaking in dormitory students. The participants were high school students, living under dormitory rules regarding the curfew, study, meals, lights-out, and wake-up times. The students were forbidden from the use of both television and personal computer in their private rooms, and only the use of a smartphone was permitted. According to prior assessment of smartphone use, we chose age-, sex-, exercise time-matched long (n = 22, >120 min) and short (n = 14, ≤60 min) groups and compared sleep-wake cycle and physiological parameters, such as cardiac ANS activity, blood pressure, and intra-aural temperature. All measurements were performed during 6:30 to 7:00 a.m. in the dormitories. Compared with the short group, the long group showed a significantly lower cardiac ANS activity (2727 ± 308 vs. 4455 ± 667 ms 2 , p = 0.030) with a tendency toward a high heart rate, in addition to later bedtimes during weekdays and more delayed wake-up times over the weekend. Blood pressure and intra-aural temperature did not differ between the groups. In this population, evening smartphone use may be associated with altered sleep-wake cycle and a diminished cardiac ANS activity after awakening could be affecting daytime activities.

Completion report : Effect of Comprehensive Yogic Breathing program on type 2 diabetes: A randomized control trial

Directory of Open Access Journals (Sweden)

V P Jyotsna

2014-01-01

Full Text Available Background: Yoga has been shown to be benefi cial in diabetes in many studies, though randomized control trials are few. The aim of this randomized control trial was to see the effect of Sudarshan Kriya and related practices (comprehensive yogic breathing program on quality of life, glycemic control, and cardiac autonomic functions in diabetes. Diabetes mellitus is a risk factor for sudden cardiac death. Cardiac autonomic neuropathy has been implicated in the causation of sudden cardiac death. Therefore, a maneuver to prevent progression of cardiac autonomic neuropathy holds signifi cance. Materials and Methods: A total of 120 patients of diabetes on oral medication and diet and exercise advice were randomized into two groups: (1 Continued to receive standard treatment for diabetes. (2 Patients administered comprehensive yogic breathing program and monitored to regularly practice yoga in addition to standard treatment of diabetes. At 6 months, quality of life and postprandial plasma glucose signifi cantly improved in the group practicing yoga compared to baseline, but there was no significant improvement in the fasting plasma glucose and glycated hemoglobin. Results: On per protocol analysis, sympathetic cardiac autonomic functions signifi cantly improved from baseline in the group practicing comprehensive yogic breathing. Conclusion: This randomized control trial points towards the beneficial effect of yogic breathing program in preventing progression of cardiac neuropathy. This has important implications as cardiac autonomic neuropathy has been considered as one of the factors for sudden cardiac deaths.Keywords: comprehensive yogic breathing program, diabetes mellitus, cardiac autonomic function

Alterations of autonomic nervous activity and energy metabolism by capsaicin ingestion during aerobic exercise in healthy men.

Science.gov (United States)

Shin, Ki Ok; Moritani, Toshio

2007-04-01

We investigated whether capsaicin ingestion (150 mg) enhances substrate oxidation associated with thermogenic sympathetic activity as an energy metabolic modulator without causing prolongation of the cardiac OT interval during aerobic exercise in humans. Ten healthy males [24.4 (4.3) y] volunteered for this study. The cardiac autonomic nervous activities evaluated by means of heart rate variability of power spectral analysis, energy metabolism, and ECG QT interval were continuously measured during 5-min rest and 30-min exercise at 50% of maximal ventilatory threshold (50% VT(max)) on a stationary ergometer with placebo or capsaicin oral administration chosen at random. The results indicated that there were no significant differences in heart rate during rest or exercise between the two trials. Autonomic nervous activity increased in the capsaicin tablet trial during exercise, but the difference did not reach statistical significance. Capsaicin, however, significantly induced a lower respiratory gas exchange ratio [0.92 (0.02) vs. 0.94 (0.02), means (SE), p means (SE), p < 0.05] during exercise. On the other hand, the data on the cardiac OT interval showed no significant difference, indicating that oral administration of capsaicin did not cause any adverse effect on cardiac depolarization-repolarization. In conclusion, it may be considered that capsaicin consumption 1 h before low intensity exercise (50% VT(max)) is a valuable supplement for the treatment of individuals with hyperlipidemia and/or obesity because it improves lipolysis without any adverse effects on the cardiac depolarization and repolarization process.

Cardiac autonomic imbalance by social stress in rodents: understanding putative biomarkers

Directory of Open Access Journals (Sweden)

Susan K Wood, Phd

2014-08-01

Full Text Available Exposure to stress or traumatic events can lead to the development of depression and anxiety disorders. In addition to the debilitating consequences on mental health, patients with psychiatric disorders also suffer from autonomic imbalance, making them susceptible to a variety of medical disorders. Emerging evidence utilizing spectral analysis of heart rate variability (HRV, a reliable noninvasive measure of cardiovascular autonomic regulation, indicates that patients with depression and various anxiety disorders (i.e., panic, social, generalized anxiety disorders, and post traumatic stress disorder are characterized by decreased HRV. Social stressors in rodents are ethologically relevant experimental stressors that recapitulate many of the dysfunctional behavioral and physiological changes that occur in psychological disorders. In this review, evidence from clinical studies and preclinical stress models identify putative biomarkers capable of precipitating the comorbidity between disorders of the mind and autonomic dysfunction. Specifically, the role of corticotropin releasing factor, neuropeptide Y and inflammation are investigated. The impetus for this review is to highlight stress-related biomarkers that may prove critical in the development of autonomic imbalance in stress -related psychiatric disorders.

Cardiovascular autonomic neuropathy in non-diabetic Nigerian ...

African Journals Online (AJOL)

Five standard cardiovascular reflex (CVR) tests namely: heart rate response to deep breathing, Valsalva manoevre and posture, as well as blood pressure response to hand grip and posture were used to evaluate the cardiac autonomic functions. A pre-tested questionnaire was administered, with neurological examination ...

Effect of Cushing's syndrome - Endogenous hypercortisolemia on cardiovascular autonomic functions.

Science.gov (United States)

Jyotsna, V P; Naseer, Ali; Sreenivas, V; Gupta, Nandita; Deepak, K K

2011-02-24

Cushing's syndrome is associated with increased cardiovascular morbidity and mortality. It's also associated with other cardiac risk factors like hypertension, diabetes mellitus and obesity. Cardiovascular autonomic function impairment could predict cardiovascular morbidity and mortality. Twenty five patients with Cushing's syndrome without diabetes and twenty five age matched healthy controls underwent a battery of cardiovascular autonomic function tests including deep breath test, Valsalva test, hand grip test, cold pressor test and response to standing from lying position. The rise in diastolic blood pressure on hand grip test and diastolic BP response to cold pressor test in Cushing's patients were significantly less compared to healthy controls (9.83 ± 3.90 vs 20.64 ± 9.55, p<0.001 and 10.09 ± 4.07 vs 15.33 ± 6.26, p<0.01 respectively). The E:I ratio on deep breathing test was also less in the patients in comparison to controls (1.36 ± 0.21 vs 1.53 ± 0.19, p<0.01). Seven patients underwent the same battery of tests 6 months after a curative surgery showing a trend towards normalization with significant improvement in expiratory to inspiratory ratio and sinus arrhythmia delta heart rate. To conclude, this study showed that chronic endogenous hypercortisolism in Cushing's is associated with an impaired sympathetic cardiovascular autonomic functioning. After a curative surgery, some of the parameters tend to improve. Copyright © 2010 Elsevier B.V. All rights reserved.

Cardiac vagal tone, a non-invasive measure of parasympathetic tone, is a clinically relevant tool in Type 1 diabetes mellitus

DEFF Research Database (Denmark)

Brock, C; Jessen, N; Brock, B

2017-01-01

AIMS: To compare a novel index of parasympathetic tone, cardiac vagal tone, with established autonomic variables and to test the hypotheses that (1) cardiac vagal tone would be associated with established time and frequency domain measures of heart rate and (2) cardiac vagal tone would be lower...... identification of people with Type 1 diabetes who should undergo formal autonomic function testing....

Autonomic control of heart rate during orthostasis and the importance of orthostatic-tachycardia in the snake Python molurus.

Science.gov (United States)

Armelin, Vinicius Araújo; da Silva Braga, Victor Hugo; Abe, Augusto Shinya; Rantin, Francisco Tadeu; Florindo, Luiz Henrique

2014-10-01

Orthostasis dramatically influences the hemodynamics of terrestrial vertebrates, especially large and elongated animals such as snakes. When these animals assume a vertical orientation, gravity tends to reduce venous return, cardiac filling, cardiac output and blood pressure to the anterior regions of the body. The hypotension triggers physiological responses, which generally include vasomotor adjustments and tachycardia to normalize blood pressure. While some studies have focused on understanding the regulation of these vasomotor adjustments in ectothermic vertebrates, little is known about regulation and the importance of heart rate in these animals during orthostasis. We acquired heart rate and carotid pulse pressure (P PC) in pythons in their horizontal position, and during 30 and 60° inclinations while the animals were either untreated (control) or upon muscarinic cholinoceptor blockade and a double autonomic blockade. Double autonomic blockade completely eradicated the orthostatic-tachycardia, and without this adjustment, the P PC reduction caused by the tilts became higher than that which was observed in untreated animals. On the other hand, post-inclinatory vasomotor adjustments appeared to be of negligible importance in counterbalancing the hemodynamic effects of gravity. Finally, calculations of cardiac autonomic tones at each position revealed that the orthostatic-tachycardia is almost completely elicited by a withdrawal of vagal drive.

Differential effects of high-fat and high-carbohydrate isoenergetic meals on cardiac autonomic nervous system activity in lean and obese women.

Science.gov (United States)

Tentolouris, N; Tsigos, C; Perea, D; Koukou, E; Kyriaki, D; Kitsou, E; Daskas, S; Daifotis, Z; Makrilakis, K; Raptis, S A; Katsilambros, N

2003-11-01

Food ingestion can influence autonomic nervous system activity. This study compares the effects of 2 different isoenergetic meals on sympathetic nervous system (SNS) activity, assessed by heart rate variability (HRV) and plasma norepinephrine (NE) levels, in lean and obese women. Fifteen lean and 15 obese healthy women were examined on 2 occasions: after a carbohydrate (CHO)-rich and after a fat-rich test meal. Measurements of blood pressure, heart rate, resting energy expenditure, plasma glucose, lipids, insulin, leptin, and NE, as well as spectral analysis of the HRV, were performed at baseline and every 1 hour for 3 hours after meals. At baseline, obese women had higher SNS activity than lean controls (higher values of low-to-high frequency ratio [LF/HF], 1.52 +/- 0.31 v 0.78 +/- 0.13, P=.04; and plasma NE levels, 405.6 +/- 197.9 v 240.5 +/- 95.8 pg/mL, Pmeal a greater increase in LF/HF and in plasma NE levels was observed in lean, compared to obese women (1.21 +/- 0.6 v 0.32 +/- 0.06, P=.04; and 102.9 +/- 35.4 v 38.7 +/- 12.3 pg/mL, P=.01, respectively), while no differences were observed after the fat-rich meal. Meal-induced thermogenesis was higher after the CHO-rich as compared to the fat-rich meal and was comparable between lean and obese women. Changes in HRV were not associated with the thermogenic response to the test meals. In conclusion, consumption of a CHO-rich meal causes greater cardiac SNS activation in lean than in obese women, while fat ingestion does not result in any appreciable change in either group. SNS activation does not appear to influence the thermic effect of the food in either lean or obese women.

The electrophysiological effects of nicotinic and electrical stimulation of intrinsic cardiac ganglia in the absence of extrinsic autonomic nerves in the rabbit heart.

Science.gov (United States)

Allen, Emily; Coote, John H; Grubb, Blair D; Batten, Trevor Fc; Pauza, Dainius H; Ng, G André; Brack, Kieran E

2018-05-22

The intrinsic cardiac nervous system (ICNS) is a rich network of cardiac nerves that converge to form distinct ganglia and extend across the heart and is capable of influencing cardiac function. To provide a picture of the neurotransmitter/neuromodulator profile of the rabbit ICNS and determine the action of spatially divergent ganglia on cardiac electrophysiology. Nicotinic or electrical stimulation was applied at discrete sites of the intrinsic cardiac nerve plexus in the Langendorff perfused rabbit heart. Functional effects on sinus rate and atrioventricular conduction were measured. Immunohistochemistry for choline acetyltransferase (ChAT), tyrosine hydroxylase (TH) and/or neuronal nitric oxide synthase (nNOS) was performed on whole-mount preparations. Stimulation within all ganglia produced either bradycardia, tachycardia or a biphasic brady-tachycardia. Electrical stimulation of the right atrial (RA) and right neuronal cluster (RNC) regions produced the greatest chronotropic responses. Significant prolongation of atrioventricular conduction (AVC) was predominant at the pulmonary vein-caudal vein region (PVCV). Neurons immunoreactive (IR) only for ChAT, or TH or nNOS were consistently located within the limits of the hilum and at the roots of the right cranial and right pulmonary veins. ChAT-IR neurons were most abundant (1946±668 neurons). Neurons IR solely for nNOS were distributed within ganglia. Stimulation of intrinsic ganglia, shown to be of phenotypic complexity but predominantly of cholinergic nature, indicates that clusters of neurons are capable of independent selective effects on cardiac electrophysiology, therefore providing a potential therapeutic target for the prevention and treatment of cardiac disease. Copyright © 2018. Published by Elsevier Inc.

Intrinsic cardiac nervous system in tachycardia induced heart failure.

Science.gov (United States)

Arora, Rakesh C; Cardinal, Rene; Smith, Frank M; Ardell, Jeffrey L; Dell'Italia, Louis J; Armour, J Andrew

2003-11-01

The purpose of this study was to test the hypothesis that early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiac function. After 2 wk of rapid ventricular pacing in nine anesthetized canines, cardiac and right atrial neuronal function were evaluated in situ in response to enhanced cardiac sensory inputs, stimulation of extracardiac autonomic efferent neuronal inputs, and close coronary arterial administration of neurochemicals that included nicotine. Right atrial neuronal intracellular electrophysiological properties were then evaluated in vitro in response to synaptic activation and nicotine. Intrinsic cardiac nicotine-sensitive, neuronally induced cardiac responses were also evaluated in eight sham-operated, unpaced animals. Two weeks of rapid ventricular pacing reduced the cardiac index by 54%. Intrinsic cardiac neurons of paced hearts maintained their cardiac mechano- and chemosensory transduction properties in vivo. They also responded normally to sympathetic and parasympathetic preganglionic efferent neuronal inputs, as well as to locally administered alpha-or beta-adrenergic agonists or angiotensin II. The dose of nicotine needed to modify intrinsic cardiac neurons was 50 times greater in failure compared with normal preparations. That dose failed to alter monitored cardiovascular indexes in failing preparations. Phasic and accommodating neurons identified in vitro displayed altered intracellular membrane properties compared with control, including decreased membrane resistance, indicative of reduced excitability. Early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiodynamics. While maintaining its capacity to transduce cardiac mechano- and chemosensory inputs, as well as inputs from extracardiac autonomic efferent neurons, intrinsic cardiac nicotine-sensitive, local-circuit neurons differentially remodel such that their capacity to

Myocardial ischaemia and the cardiac nervous system.

Science.gov (United States)

Armour, J A

1999-01-01

The intrinsic cardiac nervous system has been classically considered to contain only parasympathetic efferent postganglionic neurones which receive inputs from medullary parasympathetic efferent preganglionic neurones. In such a view, intrinsic cardiac ganglia act as simple relay stations of parasympathetic efferent neuronal input to the heart, the major autonomic control of the heart purported to reside solely in the brainstem and spinal cord. Data collected over the past two decades indicate that processing occurs within the mammalian intrinsic cardiac nervous system which involves afferent neurones, local circuit neurones (interconnecting neurones) as well as both sympathetic and parasympathetic efferent postganglionic neurones. As such, intrinsic cardiac ganglionic interactions represent the organ component of the hierarchy of intrathoracic nested feedback control loops which provide rapid and appropriate reflex coordination of efferent autonomic neuronal outflow to the heart. In such a concept, the intrinsic cardiac nervous system acts as a distributive processor, integrating parasympathetic and sympathetic efferent centrifugal information to the heart in addition to centripetal information arising from cardiac sensory neurites. A number of neurochemicals have been shown to influence the interneuronal interactions which occur within the intrathoracic cardiac nervous system. For instance, pharmacological interventions that modify beta-adrenergic or angiotensin II receptors affect cardiomyocyte function not only directly, but indirectly by influencing the capacity of intrathoracic neurones to regulate cardiomyocytes. Thus, current pharmacological management of heart disease may influence cardiomyocyte function directly as well as indirectly secondary to modifying the cardiac nervous system. This review presents a brief summary of developing concepts about the role of the cardiac nervous system in regulating the normal heart. In addition, it provides some

The effects of long-term microgravity on autonomic regulation of blood circulation in crewmembers of the international space station

Directory of Open Access Journals (Sweden)

Roman М. Baevsky

2014-11-01

Full Text Available The article presents the results of space experiment “Pneumocard”. The investigation involved all 25 Russian members of the ISS crew. The total of 226 sessions were made including 130 aboard the ISS, 50 prior to launch and 46 on return from mission. The objective was to study effects of the spaceflight factors on autonomic regulation of blood circulation, respiration and cardiac contractility during long-duration mission. The purpose was to secure new research data that would clarify our present view of adaptation mechanisms. Registered were the following signals: electrocardiogram, impedance cardiogram, seismic cardiogram, pneumotachogram, finger photoplethysmogram. A set of hard- and software was used. Autonomic regulation of blood circulation by HRV analysis was investigated. It was shown that at the onset of a space mission parasympathetic involvement in regulation increases typically with subsequent mobilization of additional functional reserve. It guided the development of a functional states mathematical model incorporating the established types of autonomic regulation. Our data evidence that the combination of HRV analysis, pre-nosology diagnosis and probabilistic estimate of the pathology risk can reinforce the medical care program in space missions.

Effects of an isotonic beverage on autonomic regulation during and after exercise

Directory of Open Access Journals (Sweden)

Moreno Isadora Lessa

2013-01-01

Full Text Available Abstract Background With prolonged physical activity, it is important to maintain adequate fluid balance. The impact of consuming isotonic drinks during and after exercise on the autonomic regulation of cardiac function is unclear. This study aimed to analyze the effects of consuming an isotonic drink on heart rate variability (HRV during and after prolonged exercise. Methods Thirty-one young males (21.55 ± 1.89 yr performed three different protocols (48 h interval between each stage: I maximal exercise test to determine the load for the protocols; II Control protocol (CP and; III. Experimental protocol (EP. The protocols consisted of 10 min at rest with the subject in the supine position, 90 min of treadmill exercise (60% of VO2 peak and 60 min of rest placed in the dorsal decubitus position. No rehydration beverage consumption was allowed during CP. During EP, however, the subjects were given an isotonic solution (Gatorade, Brazil containing carbohydrate (30 g, sodium (225 mg, chloride (210 mg and potassium (60 mg per 500 ml of the drink. For analysis of HRV data, time and frequency domain indices were investigated. HRV was recorded at rest (5–10 min, during exercise (25–30 min, 55–60 min and 85–90 min and post-exercise (5–10 min, 15–20 min, 25–30 min, 40–45 min and 55–60 min. Results Regardless of hydration, alterations in the SNS and PSNS were observed, revealing an increase in the former and a decrease in the latter. Hydrating with isotonic solution during recovery induced significant changes in cardiac autonomic modulation, promoting faster recovery of linear HRV indices. Conclusion Hydration with isotonic solution did not significantly influence HRV during exercise; however, after exercise it promoted faster recovery of linear indices.

Association between Birth Characteristics and Cardiovascular Autonomic Function at Mid-Life.

Directory of Open Access Journals (Sweden)

Nelli Perkiömäki

Full Text Available Low birth weight is associated with an increased risk of cardiovascular diseases in adulthood. As abnormal cardiac autonomic function is a common feature in cardiovascular diseases, we tested the hypothesis that low birth weight may also be associated with poorer cardiac autonomic function in middle-aged subjects.At the age of 46, the subjects of the Northern Finland Birth Cohort 1966 were invited to examinations including questionnaires about health status and life style and measurement of vagally-mediated heart rate variability (rMSSD from R-R intervals (RRi and spontaneous baroreflex sensitivity (BRS in both seated and standing positions. Maternal parameters had been collected in 1965-1966 since the 16th gestational week and birth variables immediately after delivery. For rMSSD, 1,799 men and 2,279 women without cardiorespiratory diseases and diabetes were included and 902 men and 1,020 women for BRS. The analyses were adjusted for maternal (age, anthropometry, socioeconomics, parity, gestational smoking and adult variables (life style, anthropometry, blood pressure, glycemic and lipid status potentially confounding the relationship between birth weight and autonomic function.In men, birth weight correlated negatively with seated (r = -0.058, p = 0.014 and standing rMSSD (r = -0.090, p<0.001, as well as with standing BRS (r = -0.092, p = 0.006. These observations were verified using relevant birth weight categories (<2,500 g; 2,500-3,999 g; ≥4,000 g. In women, birth weight was positively correlated with seated BRS (r = 0.081, p = 0.010, but none of the other measures of cardiovascular autonomic function. These correlations remained significant after adjustment for potential confounders (p<0.05 for all.In men, higher birth weight was independently associated with poorer cardiac autonomic function at mid-life. Same association was not observed in women. Our findings suggest that higher, not lower, birth weight in males may contribute to less

Do mobile phones pose a potential risk to autonomic modulation of the heart?

Science.gov (United States)

Barutcu, Irfan; Esen, Ali Metin; Kaya, Dayimi; Turkmen, Muhsin; Karakaya, Osman; Saglam, Mustafa; Melek, Mehmet; Çelik, Ataç; Kilit, Celal; Onrat, Ersel; Kirma, Cevat

2011-11-01

It has long been speculated that mobile phones may interact with the cardiac devices and thereby cardiovascular system may be a potential target for the electromagnetic fields emitted by the mobile phones. Therefore, the present study was designed to test possible effects of radiofrequency waves emitted by digital mobile phones on cardiac autonomic modulation by short-time heart rate variability (HRV) analysis. A total of 20 healthy young subjects were included to the study. All participants were rested in supine position at least for 15 minutes on a comfortable bed, and then time and frequency domain HRV parameters were recorded at baseline in supine position for 5 minutes. After completion of baseline records, by using a mobile GSM (Global System for Mobile Communication) phone, HRV parameters were recorded at turned off mode, at turned on mode, and at calling mode over 5 minutes periods for each stage. Neither time nor frequency domain HRV parameters altered significantly during off mode compare to their baseline values. Also, neither time nor frequency domain HRV parameters altered significantly during turned on and calling mode compared to their baseline values. Short-time exposure to electromagnetic fields emitted by mobile phone does not affect cardiac autonomic modulation in healthy subjects.

Cardiovascular autonomic control during short-term thermoneutral and cool head-out immersion.

Science.gov (United States)

Mourot, Laurent; Bouhaddi, Malika; Gandelin, Emmanuel; Cappelle, Sylvie; Dumoulin, Gilles; Wolf, Jean-Pierre; Rouillon, Jean Denis; Regnard, Jacques

2008-01-01

Moderately cold head-out water immersion stimulates both baro- and cold-receptors, and triggers complex and contradictory effects on the cardiovascular system and its autonomic nervous control. To assess the effects of water immersion and cold on cardiovascular status and related autonomic nervous activity. Hemodynamic variables and indexes of autonomic nervous activity (analysis of heart rate and blood pressure variability) were evaluated in 12 healthy subjects during 3 exposures of 20 min each in the upright position, i.e., in air (AIR, 24-25 degrees C), and during head-out water immersion at 35-36 degrees C (WIn) and 26-27 degrees C (WIc). Plasma noradrenaline, systolic and diastolic blood pressure, and total peripheral resistances were reduced during WIn compared to AIR (263.9 +/- 39.4 vs. 492.5 +/- 35.7 pg x ml(-1), 116.5 +/- 3.7 and 65.4 +/- 1.7 mmHg vs. 140.8 +/- 4.7 and 89.8 +/- 2.8 mmHg, 14.1 +/- 1.0 vs. 16.3 +/- 0.9 mmHg x L(-1) x min, respectively) while they were increased during WIc (530.8 +/- 84.7 pg ml(-1), 148.0 +/- 7.0 mmHg, 80.8 +/- 3.0 mmHg, and 25.8 +/- 1.9 mmHg x L(-1) x min, respectively). The blood pressure variability was reduced to the same extent during WIc and Win compared to AIR. Heart rate decreased during WIn (67.8 +/- 2.7 vs. 81.2 +/- 2.7 bpm during AIR), in parallel with an increased cardiac parasympathetic activity. This pattern was strengthened during WIc (55.3 +/- 2.2 bpm). Thermoneutral WI lowered sympathetic activity and arterial tone, while moderate whole-body skin cooling triggered vascular sympathetic activation. Conversely, both WI and cold triggered cardiac parasympathetic activation, highlighting a complex autonomic control of the cardiovascular system.

Research on support effectiveness modeling and simulating of aviation materiel autonomic logistics system

Science.gov (United States)

Zhou, Yan; Zhou, Yang; Yuan, Kai; Jia, Zhiyu; Li, Shuo

2018-05-01

Aiming at the demonstration of autonomic logistics system to be used at the new generation of aviation materiel in our country, the modeling and simulating method of aviation materiel support effectiveness considering autonomic logistics are studied. Firstly, this paper introduced the idea of JSF autonomic logistics and analyzed the influence of autonomic logistics on support effectiveness from aspects of reliability, false alarm rate, troubleshooting time, and support delay time and maintenance level. On this basis, the paper studies the modeling and simulating methods of support effectiveness considering autonomic logistics, and puts forward the maintenance support simulation process considering autonomic logistics. Finally, taking the typical aviation materiel as an example, this paper analyzes and verifies the above-mentioned support effectiveness modeling and simulating method of aviation materiel considering autonomic logistics.

Human autonomic rhythms: vagal cardiac mechanisms in tetraplegic subjects

Science.gov (United States)

Koh, J.; Brown, T. E.; Beightol, L. A.; Ha, C. Y.; Eckberg, D. L.

1994-01-01

1. We studied eight young men (age range: 20-37 years) with chronic, clinically complete high cervical spinal cord injuries and ten age-matched healthy men to determine how interruption of connections between the central nervous system and spinal sympathetic motoneurones affects autonomic cardiovascular control. 2. Baseline diastolic pressures and R-R intervals (heart periods) were similar in the two groups. Slopes of R-R interval responses to brief neck pressure changes were significantly lower in tetraplegic than in healthy subjects, but slopes of R-R interval responses to steady-state arterial pressure reductions and increases were comparable. Plasma noradrenaline levels did not change significantly during steady-state arterial pressure reductions in tetraplegic patients, but rose sharply in healthy subjects. The range of arterial pressure and R-R interval responses to vasoactive drugs (nitroprusside and phenylephrine) was significantly greater in tetraplegic than healthy subjects. 3. Resting R-R interval spectral power at respiratory and low frequencies was similar in the two groups. During infusions of vasoactive drugs, low-frequency R-R interval spectral power was directly proportional to arterial pressure in tetraplegic patients, but was unrelated to arterial pressure in healthy subjects. Vagolytic doses of atropine nearly abolished both low- and respiratory-frequency R-R interval spectral power in both groups. 4. Our conclusions are as follows. First, since tetraplegic patients have significant levels of low-frequency arterial pressure and R-R interval spectral power, human Mayer arterial pressure waves may result from mechanisms that do not involve stimulation of spinal sympathetic motoneurones by brainstem neurones. Second, since in tetraplegic patients, low-frequency R-R interval spectral power is proportional to arterial pressure, it is likely to be mediated by a baroreflex mechanism. Third, since low-frequency R-R interval rhythms were nearly abolished

Remodeling of intrinsic cardiac neurons: effects of β-adrenergic receptor blockade in guinea pig models of chronic heart disease.

Science.gov (United States)

Hardwick, Jean C; Southerland, E Marie; Girasole, Allison E; Ryan, Shannon E; Negrotto, Sara; Ardell, Jeffrey L

2012-11-01

Chronic heart disease induces remodeling of cardiac tissue and associated neuronal components. Treatment of chronic heart disease often involves pharmacological blockade of adrenergic receptors. This study examined the specific changes in neuronal sensitivity of guinea pig intrinsic cardiac neurons to autonomic modulators in animals with chronic cardiac disease, in the presence or absence of adrenergic blockage. Myocardial infarction (MI) was produced by ligature of the coronary artery and associated vein on the dorsal surface of the heart. Pressure overload (PO) was induced by a banding of the descending dorsal aorta (∼20% constriction). Animals were allowed to recover for 2 wk and then implanted with an osmotic pump (Alzet) containing either timolol (2 mg·kg(-1)·day(-1)) or vehicle, for a total of 6-7 wk of drug treatment. At termination, intracellular recordings from individual neurons in whole mounts of the cardiac plexus were used to assess changes in physiological responses. Timolol treatment did not inhibit the increased sensitivity to norepinephrine seen in both MI and PO animals, but it did inhibit the stimulatory effects of angiotensin II on the norepinephrine-induced increases in neuronal excitability. Timolol treatment also inhibited the increase in synaptically evoked action potentials observed in PO animals with stimulation of fiber tract bundles. These results demonstrate that β-adrenergic blockade can inhibit specific aspects of remodeling within the intrinsic cardiac plexus. In addition, this effect was preferentially observed with active cardiac disease states, indicating that the β-receptors were more influential on remodeling during dynamic disease progression.

Cardiac effects of noncardiac neoplasms

International Nuclear Information System (INIS)

Schoen, F.J.; Berger, B.M.; Guerina, N.G.

1984-01-01

Clinically significant cardiovascular abnormalities may occur as secondary manifestations of noncardiac neoplasms. The principal cardiac effects of noncardiac tumors include the direct results of metastases to the heart or lungs, the indirect effects of circulating tumor products (causing nonbacterial thrombotic endocarditis, myeloma-associated amyloidosis, pheochromocytoma-associated cardiac hypertrophy and myofibrillar degeneration, and carcinoid heart disease), and the undesired cardiotoxicities of chemotherapy and radiotherapy. 89 references

Ictal Cardiac Ryhthym Abnormalities.

Science.gov (United States)

Ali, Rushna

2016-01-01

Cardiac rhythm abnormalities in the context of epilepsy are a well-known phenomenon. However, they are under-recognized and often missed. The pathophysiology of these events is unclear. Bradycardia and asystole are preceded by seizure onset suggesting ictal propagation into the cortex impacting cardiac autonomic function, and the insula and amygdala being possible culprits. Sudden unexpected death in epilepsy (SUDEP) refers to the unanticipated death of a patient with epilepsy not related to status epilepticus, trauma, drowning, or suicide. Frequent refractory generalized tonic-clonic seizures, anti-epileptic polytherapy, and prolonged duration of epilepsy are some of the commonly identified risk factors for SUDEP. However, the most consistent risk factor out of these is an increased frequency of generalized tonic-clonic seizures (GTC). Prevention of SUDEP is extremely important in patients with chronic, generalized epilepsy. Since increased frequency of GTCS is the most consistently reported risk factor for SUDEP, effective seizure control is the most important preventive strategy.

Origin of heart rate variability and turbulence: an appraisal of autonomic modulation of cardiovascular function.

Directory of Open Access Journals (Sweden)

Federico eLombardi

2011-12-01

Full Text Available Assessment of autonomic modulation of sinus node by non-invasive techniques has provided relevant clinical information in patients with several cardiac and non-cardiac diseases and has facilitated the appraisal of neural regulatory mechanisms in normal and diseased subjects. The finding that even during resting conditions the heart period changes on a beat to beat basis and that after a premature ventricular beat there are small variations in RR interval whose measurements may be utilised to evaluate the autonomic modulation of sinus node, has provided unprecedented clinical and pathophysiological information. Heart rate variability (HRV and Heart Rate Turbulence (HRT have been extensively utilised in the clinical setting. To explain the negative predictive value of a reduced HRV it was determined that overall HRV was largely dependent on vagal mechanisms and that a reduction in HRV could reflect an increased sympathetic and a reduced vagal modulation of sinus node; i.e. an autonomic alteration favouring cardiac electrical instability. This initial interpretation was challenged by several findings indicating a greater complexity of the relationship between neural input and sinus node responsiveness as well as the possible interference with non-neural mechanisms.Under controlled conditions, however, the computation of low and high frequency components and of their ratio seems capable of providing adequate information on sympatho-vagal balance in normal subjects as well as in most patients with a preserved left ventricular function, thus providing a unique tool to investigate neural control mechanisms. Analysis on non-linear dynamics of HRV has also been utilised to describe the fractal like characteristic of the variability signal and proven effective to identify patients at risk for sudden cardiac death. A reduction on HRT parameters reflecting reduced baroreflex sensitivity as a likely result of a reduced vagal and of an increased sympathetic

Diastolic and autonomic dysfunction in early cirrhosis

DEFF Research Database (Denmark)

Dahl, Emilie Kristine; Møller, Søren; Kjær, Andreas

2014-01-01

OBJECTIVE. Presence of cardiac dysfunction in patients with advanced cirrhosis is widely accepted, but data in early stages of cirrhosis are limited. Systolic and diastolic functions, dynamics of QT-interval, and pro-atrial natriuretic peptide (pro-ANP) are investigated in patients with early stage...... cirrhosis during maximal β-adrenergic drive. MATERIAL AND METHODS. Nineteen patients with Child A (n = 12) and Child B cirrhosis (n = 7) and seven matched controls were studied during cardiac stress induced by increasing dosages of dobutamine and atropine. RESULTS. Pharmacological responsiveness was similar...... indicate that patients with early stage cirrhosis exhibit early diastolic and autonomic dysfunction as well as elevated pro-ANP. However, the cardiac chronotropic and inotropic responses to dobutamine stress were normal. The dynamics of ventricular repolarization appears normal in patients with early stage...

Cardiac autonomic dysfunction is associated with high-risk albumin-to-creatinine ratio in young adolescents with type 1 diabetes in AdDIT (adolescent type 1 diabetes cardio-renal interventional trial).

Science.gov (United States)

Cho, Yoon Hi; Craig, Maria E; Davis, Elizabeth A; Cotterill, Andrew M; Couper, Jennifer J; Cameron, Fergus J; Benitez-Aguirre, Paul Z; Dalton, R Neil; Dunger, David B; Jones, Timothy W; Donaghue, Kim C

2015-04-01

This study examined the association between cardiac autonomic dysfunction and high albumin-to-creatinine ratio (ACR) in adolescents with type 1 diabetes. Adolescents recruited as part of a multicenter screening study (n = 445, 49% female, aged 10-17 years, mean duration 6.9 years; mean HbA1c 8.4%, 68 mmol/mol) underwent a 10-min continuous electrocardiogram recording for heart rate variability analysis. Time-domain heart rate variability measures included baseline heart rate, SD of the R-R interval (SDNN), and root mean squared difference of successive R-R intervals (RMSSD). Spectral analysis included sympathetic (low-frequency) and parasympathetic (high-frequency) components. Standardized ACR were calculated from six early morning urine collections using an established algorithm, reflecting age, sex, and duration, and stratified into ACR tertiles, where the upper tertile reflects higher nephropathy risk. The upper-tertile ACR group had a faster heart rate (76 vs. 73 bpm; P < 0.01) and less heart rate variability (SDNN 68 vs. 76 ms, P = 0.02; RMSSD 63 vs. 71 ms, P = 0.04). HbA1c was 8.5% (69 mmol/mmol) in the upper tertile vs. 8.3% (67 mmol/mol) in the lower tertiles (P = 0.07). In multivariable analysis, upper-tertile ACR was associated with faster heart rate (β = 2.5, 95% CI 0.2-4.8, P = 0.03) and lower RMSSD (β = -9.5, 95% CI -18.2 to -0.8, P = 0.03), independent of age and HbA1c. Adolescents at potentially higher risk for nephropathy show an adverse cardiac autonomic profile, indicating sympathetic overdrive, compared with the lower-risk group. Longitudinal follow-up of this cohort will further characterize the relationship between autonomic and renal dysfunction and the effect of interventions in this population. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

DISORDERS OF THE AUTONOMIC NERVOUS SYSTEM IN THE CARDIOLOGY PRACTICE: FOCUS ON THE ANALYSIS OF HEART RATE VARIABILITY

Directory of Open Access Journals (Sweden)

E. B. Akhmedova

2015-09-01

Full Text Available Heart rate variability (HRV in patients with ischemic heart disease, a life-threatening heart rhythm disorders, as well as diabetes mellitus (DM is considered. A significant association between the autonomic regulation of the cardiovascular system and death from cardiovascular causes is identified. The reactions of the autonomic nervous system (ANS can serve as a precipitating factor of arrhythmias in patients with heart disorders. Analysis of HRV at rest is the main and informative method for determination of the ANS disorders. HRV decreases greatly in patients with acute myocardial infarction, cardiac arrhythmia, and DM, predicting a high risk of death. The leading cause of death in diabetic patients is cardiac autonomic neuropathy, with the development of "silent" ischemia and painless myocardial infarction. Autonomic regulation of the heart rate should be assessed for early diagnosis and prevention of complications in the form of sudden death.

[A role of the autonomic nervous system in cerebro-cardiac disorders].

Science.gov (United States)

Basantsova, N Yu; Tibekina, L M; Shishkin, A N

The authors consider anatomical/physiological characteristics and a role of different autonomic CNS regions, including insula cortex, amygdala complex, anterior cingulate cortex, ventral medial prefrontal cortex, hypothalamus and epiphysis, involved in the regulation of cardiovascular activity. The damage of these structures, e.g., due to the acute disturbance of cerebral blood circulation, led to arrhythmia, including fatal arrhythmia, in previously intact myocardium; systolic and diastolic dysfunction, ischemic changes considered in the frames of cerebro-cardial syndrome. On the cellular level, the disturbance of autonomic regulation resulted in catechol amine excitotoxicity, oxidative stress and free radical myocardium injury.

Medulla oblongata damage and cardiac autonomic dysfunction in Parkinson disease.

Science.gov (United States)

Pyatigorskaya, Nadya; Mongin, Marie; Valabregue, Romain; Yahia-Cherif, Lydia; Ewenczyk, Claire; Poupon, Cyril; Debellemaniere, Eden; Vidailhet, Marie; Arnulf, Isabelle; Lehéricy, Stephane

2016-12-13

To characterize medulla oblongata damage using diffusion tensor imaging (DTI) in Parkinson disease (PD) and correlate it with dysfunction of the cardiac sympathetic/vagal balance. Fifty-two patients with PD and 24 healthy controls were included in the study. All participants underwent clinical examination and 3T MRI using 3D T1-weighted imaging and DTI. DTI metrics were calculated within manually drawn regions of interest. Heart rate variability was evaluated using spectral analysis of the R-R cardiac interval during REM and slow-wave sleep based on continuous overnight electrocardiographic monitoring. Respiratory frequency was measured in 30-second contiguous epochs of REM and slow-wave sleep. The relationships between imaging and cardiac variables were calculated using partial correlations followed by the multiple comparisons permutation approach. The changes in heart rate and respiratory frequency variability from slow-wave sleep to REM sleep in healthy controls were no longer detectable in patients with PD. There were significant increases in the mean (p = 0.006), axial (p = 0.006), and radial diffusivities (p = 0.005) in the medulla oblongata of patients with PD. In PD, diffusion changes were specifically correlated with a lower heart rate and respiratory frequency variability during REM sleep. This study provides evidence that medulla oblongata damage underlies cardiac sympathetic/vagal balance and respiratory dysfunction in patients with PD. © 2016 American Academy of Neurology.

A STUDY ON CARDIOVASCULAR AUTONOMIC FUNCTIONS IN CAREGIVERS OF STROKE PATIENTS

Directory of Open Access Journals (Sweden)

Ghouse Mubarak

2017-08-01

Full Text Available BACKGROUND Stroke (cerebrovascular accident is an important cause of disability in countries like India and longterm care of these bedridden patients is usually undertaken by the family members. A caregiver is a person who takes responsibility for those who cannot completely care for themselves. Taking care of a chronically ill member in the family usually causes stress to the caregiver causing disturbances in the autonomic function. Thus, the present study is undertaken to find out the effect of longterm caregiving on cardiovascular autonomic functions in a caregiver. MATERIALS AND METHODS 57 caregivers of post-stroke bedridden patients, both male and female, were included in this longitudinal study. Parasympathetic activity was assessed by observing the heart rate changes to immediate standing from lying down position, heart rate changes during deep breathing and heart rate changes during Valsalva manoeuvre. Sympathetic activity was assessed by observing blood pressure changes on immediate standing from lying down position and blood pressure changes during sustained hand grip. RESULTS The results of the present study showed statistically significant decrease in Valsalva ratio, decrease in the heart rate following deep breathing and statistically significant increase in systolic blood pressure in response to immediate standing suggestive of autonomic imbalance. CONCLUSION Our findings suggest that longterm caregiving is accompanied by dysfunction of the cardiac autonomic nervous system, and these individuals are more prone to autonomic neuropathy.

Nature's Autonomous Oscillators

Science.gov (United States)

Mayr, H. G.; Yee, J.-H.; Mayr, M.; Schnetzler, R.

2012-01-01

Nonlinearity is required to produce autonomous oscillations without external time dependent source, and an example is the pendulum clock. The escapement mechanism of the clock imparts an impulse for each swing direction, which keeps the pendulum oscillating at the resonance frequency. Among nature's observed autonomous oscillators, examples are the quasi-biennial oscillation and bimonthly oscillation of the Earth atmosphere, and the 22-year solar oscillation. The oscillations have been simulated in numerical models without external time dependent source, and in Section 2 we summarize the results. Specifically, we shall discuss the nonlinearities that are involved in generating the oscillations, and the processes that produce the periodicities. In biology, insects have flight muscles, which function autonomously with wing frequencies that far exceed the animals' neural capacity; Stretch-activation of muscle contraction is the mechanism that produces the high frequency oscillation of insect flight, discussed in Section 3. The same mechanism is also invoked to explain the functioning of the cardiac muscle. In Section 4, we present a tutorial review of the cardio-vascular system, heart anatomy, and muscle cell physiology, leading up to Starling's Law of the Heart, which supports our notion that the human heart is also a nonlinear oscillator. In Section 5, we offer a broad perspective of the tenuous links between the fluid dynamical oscillators and the human heart physiology.

Effect of Roux-en-Y gastric bypass surgery on ventricular function and cardiac risk factors in obese patients: a systematic review

Directory of Open Access Journals (Sweden)

Alireza Abdollahi Moghaddam

2016-03-01

Full Text Available Introduction: Weight gain and obesity are two important public health problems, which are associated with many diseases such as cardiovascular disorders. Various policies such as bariatric surgery have been proposed for the treatment of morbid obesity. Methods: PubMed and Scopus were searched thoroughly with the following search terms (roux-en-y gastric bypass surgery AND (ventricular function, OR cardiac risk factors OR heart AND (BMI OR body mass index to find the articles in which the effect of roux-en-Y gastric bypass (RYGB surgery had been evaluated in severely obese patients.Result: Out of 120 articles which were found in PubMed, and 28 records which were found in Scopus, only 18 articles fully met the inclusion criteria. Out of 2740 participants in the included studied, 1706 were patients with body mass index (BMI over 40 kg/m2 who had undergone RYGB surgery, and 1034 were control participants. Results of the studies showed that RYGB surgery could reduce BMI, and cardiac risk factors, and improve diastolic function, systolic and diastolic blood pressures, and aortic function, postoperatively.Discussion: Obesity is associated with increased risk of cardiovascular diseases, impaired cardiac function, and hypertension. It is shown that RYGB surgery reduces the serum level of biochemical markers of cardiac diseases. Cardiac structure, parasympathetic indices of autonomic function, coronary circulatory function, hypertension, epicardial fat thickness, and ventricular performance improve after bariatric surgery.Conclusions: It is concluded that RYGB surgery is an effective strategy to improve ventricular function and cardiac risk factors in morbid obese patients.

Is Baseline Cardiac Autonomic Modulation Related to Performance and Physiological Responses Following a Supramaximal Judo Test?

Science.gov (United States)

Blasco-Lafarga, Cristina; Martínez-Navarro, Ignacio; Mateo-March, Manuel

2013-01-01

Little research exists concerning Heart Rate (HR) Variability (HRV) following supramaximal efforts focused on upper-body explosive strength-endurance. Since they may be very demanding, it seems of interest to analyse the relationship among performance, lactate and HR dynamics (i.e. HR, HRV and complexity) following them; as well as to know how baseline cardiac autonomic modulation mediates these relationships. The present study aimed to analyse associations between baseline and post-exercise HR dynamics following a supramaximal Judo test, and their relationship with lactate, in a sample of 22 highly-trained male judoists (20.70±4.56 years). A large association between the increase in HR from resting to exercise condition and performance suggests that individuals exerted a greater sympathetic response to achieve a better performance (Rating of Perceived Exertion: 20; post-exercise peak lactate: 11.57±2.24 mmol/L; 95.76±4.13 % of age-predicted HRmax). Athletes with higher vagal modulation and lower sympathetic modulation at rest achieved both a significant larger ∆HR and a faster post-exercise lactate removal. A enhanced resting parasympathetic modulation might be therefore related to a further usage of autonomic resources and a better immediate metabolic recovery during supramaximal exertions. Furthermore, analyses of variance displayed a persistent increase in α1 and a decrease in lnRMSSD along the 15 min of recovery, which are indicative of a diminished vagal modulation together with a sympathovagal balance leaning to sympathetic domination. Eventually, time-domain indices (lnRMSSD) showed no lactate correlations, while nonlinear indices (α1 and lnSaEn) appeared to be moderate to strongly correlated with it, thus pointing to shared mechanisms between neuroautonomic and metabolic regulation. PMID:24205273

Potential Association of Triglyceride Glucose Index with Cardiac Autonomic Neuropathy in Type 2 Diabetes Mellitus Patients.

Science.gov (United States)

Akbar, Md; Bhandari, Uma; Habib, Anwar; Ahmad, Razi

2017-07-01

Cardiac autonomic neuropathy (CAN) is a common and most neglected complication of diabetes, estimated to be roughly 8% in recently diagnosed patients and greater than 50% in patients with chronic disease history. The insulin resistance (IR) itself is bidirectionally associated with increased risk of type 2 diabetes mellitus (T2DM) and CAN is a predisposing factor. The primary objective of the present study was aimed to find a correlation of triglyceride glucose index (TyG index) in CAN patients along with the prevalence of CAN in T2DM patients as a secondary objective. This prevalence study was conducted on 202 patients visiting the diabetic clinic of Hamdard Institute of Medical Sciences and Research, Jamia Hamdard (HIMSR) teaching hospital in New Delhi, India who fulfilled the inclusion criteria. The Ewings autonomic function test was used for diagnosis of CAN. TyG index was calculated for patients based on fasting levels of glucose and triglyceride. The CAN was diagnosed in 62 participants out of 202 T2DM patients (overall prevalence 30.7%). The mean ± standard deviation (SD) for TyG index was 10.3 ± 0.2 and 9.5 ± 0.2 in CAN positive, T2DM patients, respectively. The difference of TyG index, in CAN positive and T2DM patients, was highly significant (P index, duration, and age with patient groups. TyG index showed a positive correlation with heart rate during deep breathing (HRD), heart rate variation during standing (HRS), blood pressure (BP) response to handgrip and BP response to standing. Our finding highlights the TyG index, low-cost IR index, might be useful as an alternative tool for the early screening of patients at a high risk of diabetic neuropathy. © 2017 The Korean Academy of Medical Sciences.

Autonomic Neuropathy

Science.gov (United States)

... risk of autonomic neuropathy. Other diseases. Amyloidosis, porphyria, hypothyroidism and cancer (usually due to side effects from treatment) may also increase the risk of autonomic neuropathy. ...

Effects of Escitalopram on Autonomic Function in Posttraumatic Stress Disorder Among Veterans of Operations Enduring Freedom and Iraqi Freedom (OEF/OIF).

Science.gov (United States)

Ramaswamy, Sriram; Selvaraj, Vithyalakshmi; Driscoll, David; Madabushi, Jayakrishna S; Bhatia, Subhash C; Yeragani, Vikram

2015-01-01

Posttraumatic stress disorder is a chronic, debilitating condition that has become a growing concern among combat veterans. Previous research suggests that posttraumatic stress disorder disrupts normal autonomic responding and may increase the risk of cardiovascular disease and mortality. Measures of heart rate variability and QT interval variability have been used extensively to characterize sympathetic and parasympathetic influences on heart rate in a variety of psychiatric populations. The objective of this study was to better understand the effects of pharmacological treatment on autonomic reactivity in posttraumatic stress disorder. A 12-week, Phase IV, prospective, open-label trial of escitalopram in veterans with combat-related posttraumatic stress disorder and comorbid depression. An outpatient mental health clinic at a Veterans Affairs Medical Center. Eleven male veterans of Operations Enduring Freedom and Iraqi Freedom diagnosed with posttraumatic stress disorder and comorbid depression. Autonomic reactivity was measured by examining heart rate variability and QT interval variability. Treatment safety and efficacy were also evaluated pre- and post-treatment. We observed a reduction in posttraumatic stress disorder and depression symptoms from pre- to post-treatment, and escitalopram was generally well tolerated in our sample. In addition, we observed a decrease in high frequency heart rate variability and an increase in QT variability, indicating a reduction in cardiac vagal function and heightened sympathetic activation. These findings suggest that escitalopram treatment in patients with posttraumatic stress disorder and depression can trigger changes in autonomic reactivity that may adversely impact cardiovascular health.

Clozapine-Induced Cardiovascular Side Effects and Autonomic Dysfunction: A Systematic Review

Directory of Open Access Journals (Sweden)

Jessica W. Y. Yuen

2018-04-01

Full Text Available Background: Clozapine is the antipsychotic of choice for treatment-resistant schizophrenia and has minimal risk for extrapyramidal symptoms. Therapeutic benefits, however, are accompanied by a myriad of cardiometabolic side-effects. The specific reasons for clozapine's high propensity to cause adverse cardiometabolic events remain unknown, but it is believed that autonomic dysfunction may play a role in many of these.Objective: This systematic review summarizes the literature on autonomic dysfunction and related cardiovascular side effects associated with clozapine treatment.Method: A search of the EMBASE, MEDLINE, and EBM Cochrane databases was conducted using the search terms antipsychotic agents, antipsychotic drug*, antipsychotic*, schizophrenia, schizophren*, psychos*, psychotic*, mental ill*, mental disorder*, neuroleptic*, cardiovascular*, cardiovascular diseases, clozapine*, clozaril*, autonomic*, sympathetic*, catecholamine*, norepinephrine, noradrenaline, epinephrine, adrenaline.Results: The search yielded 37 studies that were reviewed, of which only 16 studies have used interventions to manage cardiovascular side effects. Side effects reported in the studies include myocarditis, orthostatic hypotension and tachycardia. These were attributed to sympathetic hyperactivity, decreased vagal contribution, blockade of cholinergic and adrenergic receptors, reduced heart rate variability and elevated catecholamines with clozapine use. Autonomic neuropathy was identified by monitoring blood pressure and heart rate changes in response to stimuli and by spectral analysis of heart rate variability. Metoprolol, lorazepam, atenolol, propranolol, amlodipine, vasopressin and norepinephrine infusion were used to treat tachycardia and fluctuations in blood pressure, yet results were limited to case reports.Conclusion: The results indicate there is a lack of clinical studies investigating autonomic dysfunction and a limited use of interventions to manage

Diesel Exhaust Inhalation Increases Cardiac Output, Bradyarrhythmias, and Parasympathetic Tone in Aged Heart Failure-Prone Rats

Science.gov (United States)

Acute air pollutant inhalation is linked to adverse cardiac events and death, and hospitalizations for heart failure. Diesel exhaust (DE) is a major air pollutant suspected to exacerbate preexisting cardiac conditions, in part, through autonomic and electrophysiologic disturbance...

Neonatal autonomic function after pregnancy complications and early cardiovascular development.

Science.gov (United States)

Aye, Christina Y L; Lewandowski, Adam James; Oster, Julien; Upton, Ross; Davis, Esther; Kenworthy, Yvonne; Boardman, Henry; Yu, Grace Z; Siepmann, Timo; Adwani, Satish; McCormick, Kenny; Sverrisdottir, Yrsa B; Leeson, Paul

2018-05-23

Heart rate variability (HRV) has emerged as a predictor of later cardiac risk. This study tested whether pregnancy complications that may have long-term offspring cardiac sequelae are associated with differences in HRV at birth, and whether these HRV differences identify abnormal cardiovascular development in the postnatal period. Ninety-eight sleeping neonates had 5-min electrocardiogram recordings at birth. Standard time and frequency domain parameters were calculated and related to cardiovascular measures at birth and 3 months of age. Increasing prematurity, but not maternal hypertension or growth restriction, was associated with decreased HRV at birth, as demonstrated by a lower root mean square of the difference between adjacent NN intervals (rMSSD) and low (LF) and high-frequency power (HF), with decreasing gestational age (p < 0.001, p = 0.009 and p = 0.007, respectively). We also demonstrated a relative imbalance between sympathetic and parasympathetic tone, compared to the term infants. However, differences in autonomic function did not predict cardiovascular measures at either time point. Altered cardiac autonomic function at birth relates to prematurity rather than other pregnancy complications and does not predict cardiovascular developmental patterns during the first 3 months post birth. Long-term studies will be needed to understand the relevance to cardiovascular risk.

Complex Nonlinear Autonomic Nervous System Modulation Link Cardiac Autonomic Neuropathy and Peripheral Vascular Disease

Directory of Open Access Journals (Sweden)

Kinda eKhalaf

2015-03-01

Full Text Available Background: Physiological interactions are abundant within, and between, body systems. These interactions may evolve into discrete states during pathophysiological processes resulting from common mechanisms. An association between arterial stenosis, identified by low ankle-brachial pressure index (ABPI and cardiovascular disease (CVD as been reported. Whether an association between vascular calcification - characterized by high ABPI and a different pathophysiology - is similarly associated with CVD, has not been established. The current study aims to investigate the association between ABPI, and cardiac rhythm, as an indicator of cardiovascular health and functionality, utilising heart rate variability (HRV.Methods and Results: Two hundred and thirty six patients underwent ABPI assessment. Standard time and frequency domain, and non-linear HRV measures were determined from 5-minute electrocardiogram. ABPI data were divided into normal (n=101, low (n=67 and high (n=66 and compared to HRV measures.(DFAα1 and SampEn were significantly different between the low ABPI, high ABPI and control groups (p<0.05.Conclusion: A possible coupling between arterial stenosis and vascular calcification with decreased and increased HRV respectively was observed. Our results suggest a model for interpreting the relationship between vascular pathophysiology and cardiac rhythm. The cardiovascular system may be viewed as a complex system comprising a number of interacting subsystems. These cardiac and vascular subsystems/networks may be coupled and undergo transitions in response to internal or external perturbations. From a clinical perspective, the significantly increased sample entropy compared to the normal ABPI group and the decreased and increased complex correlation properties measured by DFA for the low and high ABPI groups respectively, may be useful indicators that a more holistic treatment approach in line with this more complex clinical picture is required.

QTc prolongation in Black diabetic subjects with cardiac autonomic ...

African Journals Online (AJOL)

ed QT (QTc) in diabetic individuals with cardiac auto- .... standing compared to the R-R at the 15th beat (30:15) was calculated. Abnormal .... tion between QTc and age (Pearson's univariate analysis r=0.080 ..... Diagnosis and management of.

Cardiac autonomic response following high-intensity running work-to-rest interval manipulation.

Science.gov (United States)

Cipryan, Lukas; Laursen, Paul B; Plews, Daniel J

2016-10-01

The cardiorespiratory, cardiac autonomic (via heart rate variability (HRV)) and plasma volume responses to varying sequences of high-intensity interval training (HIT) of consistent external work were investigated. Twelve moderately trained males underwent three HIT bouts and one control session. The HIT trials consisted of warm-up, followed by 12 min of 15 s, 30 s or 60 s work:relief HIT sequences at an exercise intensity of 100% of the individual velocity at [Formula: see text]O2max (v[Formula: see text]O2max), interspersed by relief intervals at 60% [Formula: see text]O2max (work/relief ratio = 1). HRV was evaluated via the square root of the mean sum of the squared differences between R-R intervals (rMSSD) before, 1 h, 3 h and 24 h after the exercise. Plasma volume was assessed before, immediately after, and 3 h and 24 h after. There were no substantial between-trial differences in acute cardiorespiratory responses. The rMSSD values remained decreased 1 h after the exercise cessation in all exercise groups. The rMSSD subsequently increased between 1 h and 3 h after exercise, with the most pronounced change in the 15/15 group. There were no relationships between HRV and plasma volume. All HIT protocols resulted in similar cardiorespiratory responses with slightly varying post-exercise HRV responses, with the 30/30 protocol eliciting the least disruption to post-exercise HRV. These post-exercise HRV findings suggest that the 30/30 sequence may be the preferable HIT prescription when the between-training period is limited.

Gritty people try harder: grit and effort-related cardiac autonomic activity during an active coping challenge.

Science.gov (United States)

Silvia, Paul J; Eddington, Kari M; Beaty, Roger E; Nusbaum, Emily C; Kwapil, Thomas R

2013-05-01

Grit, a recently proposed personality trait associated with persistence for long-range goals, predicts achievement in a wide range of important life outcomes. Using motivational intensity theory, the present research examined the physiological underpinnings of grit during an active coping task. Forty young adults completed the Short Grit Scale and worked on a self-paced mental effort task. Effort-related autonomic nervous system (ANS) activity was assessed using impedance cardiography, which yielded measures of sympathetic activity (pre-ejection period; PEP) and parasympathetic activity (respiratory sinus arrhythmia; RSA). Multilevel models revealed that people high on the Perseverance of Effort subscale showed autonomic coactivation: both PEP and RSA became stronger during the task, reflecting higher activity of both ANS divisions. The Consistency of Interest subscale, in contrast, predicted only weaker sympathetic activity (slower PEP). Taken together, the findings illuminate autonomic processes associated with how "gritty" people pursue goals, and they suggest that more attention should be paid to the facets' distinct effects. Copyright © 2013 Elsevier B.V. All rights reserved.

Methyl-CpG binding-protein 2 function in cholinergic neurons mediates cardiac arrhythmogenesis.

Science.gov (United States)

Herrera, José A; Ward, Christopher S; Wehrens, Xander H T; Neul, Jeffrey L

2016-11-15

Sudden unexpected death occurs in one quarter of deaths in Rett Syndrome (RTT), a neurodevelopmental disorder caused by mutations in Methyl-CpG-binding protein 2 (MECP2). People with RTT show a variety of autonomic nervous system (ANS) abnormalities and mouse models show similar problems including QTc interval prolongation and hypothermia. To explore the role of cardiac problems in sudden death in RTT, we characterized cardiac rhythm in mice lacking Mecp2 function. Male and female mutant mice exhibited spontaneous cardiac rhythm abnormalities including bradycardic events, sinus pauses, atrioventricular block, premature ventricular contractions, non-sustained ventricular arrhythmias, and increased heart rate variability. Death was associated with spontaneous cardiac arrhythmias and complete conduction block. Atropine treatment reduced cardiac arrhythmias in mutant mice, implicating overactive parasympathetic tone. To explore the role of MeCP2 within the parasympathetic neurons, we selectively removed MeCP2 function from cholinergic neurons (MeCP2 ChAT KO), which recapitulated the cardiac rhythm abnormalities, hypothermia, and early death seen in RTT male mice. Conversely, restoring MeCP2 only in cholinergic neurons rescued these phenotypes. Thus, MeCP2 in cholinergic neurons is necessary and sufficient for autonomic cardiac control, thermoregulation, and survival, and targeting the overactive parasympathetic system may be a useful therapeutic strategy to prevent sudden unexpected death in RTT.

The effects of proton pump inhibitors on autonomic tone in patients with erosive and non-erosive esophagitis.

Science.gov (United States)

Jones, E L; Perring, S; Khattab, A; Allenby-Smith, O

2016-05-01

Reduction in autonomic tone as measured by heart rate variability (HRV) has been associated with various inflammatory conditions including reflux disease. The nature of and permanence of this damage have not been fully assessed. Fourteen individuals with non-erosive reflux disease (NERD) and 10 individuals with erosive reflux disease (ERD) as identified on endoscopy were assessed for HRV prior to starting a course of proton pump inhibitor (PPI) therapy and 8 weeks from the start of PPI therapy. Reflux symptoms were significantly improved by PPI therapy (p = 0.001), with no significant difference in reflux symptoms between the NERD and ERD groups either before (p = 0.45) or following therapy (p = 0.17). The ERD group displayed reduced HRV prior to PPI therapy as compared with a non-symptomatic group. There was significant improvement of HRV resulting from PPI therapy in the ERD group as measured by inspiration/expiration ratio on forced breathing (p = 0.02), Valsalva ratio (p = 0.03), and extended metronome-guided breathing at 6 breaths per minute (p = 0.03). While a similar pattern was seen in the NERD group, the effects were not as strong and did not reach statistical significance. The results are consistent with a growing body of evidence that cardiac autonomic neuropathy as measured by HRV is associated with gastro-esophageal reflux disease and also suggest that successful treatment of the inflammation can lead to reversal of the deterioration of autonomic tone associated with that inflammation. © 2016 John Wiley & Sons Ltd.

Sinoatrial tissue of crucian carp heart has only negative contractile responses to autonomic agonists

Directory of Open Access Journals (Sweden)

Hälinen Mervi

2010-06-01

Full Text Available Abstract Background In the anoxia-tolerant crucian carp (Carassius carassius cardiac activity varies according to the seasons. To clarify the role of autonomic nervous control in modulation of cardiac activity, responses of atrial contraction and heart rate (HR to carbacholine (CCh and isoprenaline (Iso were determined in fish acclimatized to winter (4°C, cold-acclimated, CA and summer (18°C, warm-acclimated, WA temperatures. Results Inhibitory action of CCh was much stronger on atrial contractility than HR. CCh reduced force of atrial contraction at an order of magnitude lower concentrations (EC50 2.75-3.5·10-8 M in comparison to its depressive effect on HR (EC50 1.23-2.02·10-7 M (P -8 M and 10-7 M CCh, respectively (P + current, IK,CCh, with an EC50 value of 3-4.5·10-7 M and inhibited Ca2+ current (ICa by 28 ± 8% and 51 ± 6% at 10-7 M and 10-6 M, respectively. These currents can explain the shortening of AP. Iso did not elicit any responses in crucian carp sinoatrial preparations nor did it have any effect on atrial ICa, probably due to the saturation of the β-adrenergic cascade in the basal state. Conclusion In the crucian carp, HR and force of atrial contraction show cardio-depressive responses to the cholinergic agonist, but do not have any responses to the β-adrenergic agonist. The scope of inhibitory regulation by CCh is increased by the high basal tone of the adenylate cyclase-cAMP cascade. Higher concentrations of CCh were required to induce IK,CCh and inhibit ICa than was needed for CCh's negative inotropic effect on atrial muscle suggesting that neither IK,CCh nor ICa alone can mediate CCh's actions but they might synergistically reduce AP duration and atrial force production. Autonomic responses were similar in CA winter fish and WA summer fish indicating that cardiac sensitivity to external modulation by the autonomic nervous system is not involved in seasonal acclimatization of the crucian carp heart to cold and anoxic

Metabolic and cardiovascular responses to epinephrine in diabetic autonomic neuropathy

DEFF Research Database (Denmark)

Hilsted, J; Richter, E; Madsbad, S

1987-01-01

with autonomic neuropathy (P less than 0.01) but was unchanged in the other groups. Since cardiac output increased to a similar extent in the three groups, the decrease in blood pressure was due to a significantly larger decrease (P less than 0.01) in total peripheral vascular resistance in the patients......Norepinephrine-induced vasoconstriction, which is mediated by alpha-adrenergic receptors, is accentuated in patients with autonomic neuropathy. In contrast, responses mediated by beta-adrenergic receptors, including vasodilatation and metabolic changes, have not been evaluated in these patients....... To study these responses, we administered epinephrine in a graded intravenous infusion (0.5 to 5 micrograms per minute) to seven diabetic patients without neuropathy, seven diabetic patients with autonomic neuropathy, and seven normal subjects. Mean arterial pressure decreased significantly in the patients...

Single unit activity in the medial prefrontal cortex during Pavlovian heart rate conditioning: Effects of peripheral autonomic blockade.

Science.gov (United States)

Powell, D A; Ginsberg, Jay P

2005-11-01

Electrical activity was recorded from single neurons in the medial prefrontal cortex of rabbits during differential Pavlovian heart rate (HR) conditioning. A heterogeneous population of cells were found, some of which showed CS-evoked increases and others CS-evoked decreases in discharge, while some cells were biphasic. A subset of cells also showed trial-related changes in discharge that were related to acquisition of the HR discrimination between the reinforced CS+ and non-reinforced CS-. Administration of the peripheral cholinergic antagonist, methylscopolamine, and the andrenergic antagonist, atenolol, either increased or decreased maintained baseline activity of many cells, but had little or no effect on the CS-evoked activity of these cells. Waveform changes also did not result from administration of these drugs. This finding suggests that CS-evoked mPFC activity is not being driven by cardiac afferent input to CNS cardiac control centers. Previous studies have shown that ibotenic acid lesions of this area greatly decreases the magnitude of decelerative heart rate conditioned responses; the latter finding, plus the results of the present study, suggest that processing of CS/US contingencies by the prefrontal cortex contributes to the acquisition of autonomic changes during Pavlovian conditioning.

Methods of investigation for cardiac autonomic dysfunction in human research studies

DEFF Research Database (Denmark)

Bernardi, Luciano; Spallone, Vincenza; Stevens, Martin

2011-01-01

This consensus document provides evidence-based guidelines regarding the evaluation of diabetic cardiovascular autonomic neuropathy (CAN) for human research studies as a result of the work of the CAN Subcommittee of the Toronto Diabetic Neuropathy Expert Group. The CAN subcommittee critically...... reviewed the limitations and strengths of the available diagnostic approaches for CAN and the need for developing new tests for autonomic function. It was concluded that the most sensitive and specific approaches currently available to evaluate CAN in clinical research are: 1) heart rate variability, 2......) baroreflex sensitivity, 3) muscle sympathetic nerve activity, 4) plasma catecholamines, and 5) heart sympathetic imaging. It was also recommended that efforts should be undertaken to develop new non-invasive and safe CAN tests to be used in clinical research, with a higher sensitivity and specificity...

Exercise training starting at weaning age preserves cardiac pacemaker function in adulthood of diet-induced obese rats.

Science.gov (United States)

Carvalho de Lima, Daniel; Guimarães, Juliana Bohnen; Rodovalho, Gisele Vieira; Silveira, Simonton Andrade; Haibara, Andrea Siqueira; Coimbra, Cândido Celso

2014-08-01

Peripheral sympathetic overdrive in young obese subjects contributes to further aggravation of insulin resistance, diabetes, and hypertension, thus inducing worsening clinical conditions in adulthood. Exercise training has been considered a strategy to repair obesity autonomic dysfunction, thereby reducing the cardiometabolic risk. Therefore, the aim of this study was to assess the effect of early exercise training, starting immediately after weaning, on cardiac autonomic control in diet-induced obese rats. Male Wistar rats (weaning) were divided into four groups: (i) a control group (n = 6); (ii) an exercise-trained control group (n = 6); (iii) a diet-induced obesity group (n = 6); and (iv) an exercise-trained diet-induced obesity group (n = 6). The development of obesity was induced by 9 weeks of palatable diet intake, and the training program was implemented in a motor-driven treadmill (5 times per week) during the same period. After this period, animals were submitted to vein and artery catheter implantation to assess cardiac autonomic balance by methylatropine (3 mg/kg) and propranolol (4 mg/kg) administration. Exercise training increased running performance in both groups (p Exercise training also prevented the increased resting heart rate in obese rats, which seemed to be related to cardiac pacemaker activity preservation (p exercise program beginning at weaning age prevents cardiovascular dysfunction in obese rats, indicating that exercise training may be used as a nonpharmacological therapeutic strategy for the treatment of cardiometabolic diseases.

Autonomous Control, Climate and Environmental Changes Effects ...

African Journals Online (AJOL)

Autonomous Control, Climate and Environmental Changes Effects on Trypanosomiasis in Sub-Saharan Africa: A Review. ... African trypanosomiasis is a parasitic disease that causes serious economic losses in livestock due to anemia, loss of condition and emaciation. The disease when neglected is lethal and untreated ...

Low heart rate variability in unemployed men: The possible mediating effects of life satisfaction.

Science.gov (United States)

Jandackova, V K; Jackowska, M

2015-01-01

Unemployment has consistently been associated with increased risk of cardiovascular disease and premature mortality, and impaired autonomic modulation of the heart might be one mechanism partly explaining this. This study examined whether the possible effect of unemployment on cardiac autonomic modulation is in part mediated by lower psychological well-being. The sample comprised of 15 job-seeking men aged 30-49 years matched with 15 employed men on age, type of job, smoking habits, alcohol intake, frequency of physical activity, and body mass index. Heart rate variability (HRV) during a modified orthostatic test was the measure of cardiac autonomic modulation, and life satisfaction was the measure of psychological well-being. Unemployed men had significantly lower overall HRV (p = .040) than controls. This association was partially mediated through lower general life satisfaction, and in particular, by low financial satisfaction, independently of demographic and/or behavioral factors that influence HRV. These findings suggest that seeking a job is a potential stressor that may reduce overall HRV and contribute towards disturbance of cardiac autonomic modulation in men. Financial difficulties could be one mechanism through which the effects of unemployment are translated into impaired autonomic modulation.

Effect of Sleep/Wake Cycle on Autonomic Regulation

International Nuclear Information System (INIS)

Jabeen, S.

2015-01-01

Objective: To evaluate the association between irregular sleep/wake cycle in shift workers and autonomic regulation. Study Design: Cross-sectional, analytical study. Place and Duration of Study: Dow University Hospital, Karachi, from August to November 2013. Methodology: All health care providers working in rotating shifts making a total (n=104) were included. Instrument was an integrated questionnaire applied to assess autonomic regulation, taken from Kroz et al. on scoring criteria, ranging from 18 - 54, where higher rating signifies strong autonomic regulation, indicating a stable Autonomic Nervous System (ANS) and vice versa. Participants were interviewed and their response was recorded by the investigator. Influence of sleep misalignment was measured quantitatively to extract index of autonomic activity. Results: There was a reduced trend in autonomic strength amongst shift workers. The mean score obtained on the Autonomic Scale was 37.8 ± 5.9. Conclusion: Circadian misalignment has an injurious influence on ANS which might be valuable in controlling autonomic dysfunction that leads to fatal triggers in rotating shift workers. (author)

Plasma DNA Mediate Autonomic Dysfunctions and White Matter Injuries in Patients with Parkinson’s Disease

Directory of Open Access Journals (Sweden)

Meng-Hsiang Chen

2017-01-01

Full Text Available Background. Cardiovascular autonomic dysfunction is well known in Parkinson’s disease (PD presentation and it produces hypoperfusion of vital organs. The association between cardiovascular autonomic dysfunction and oxidative stress was examined in previous animal models. Oxidative stress and neuroinflammation were thought to have roles in PD pathogenesis. Owing to the relative low intrinsic antioxidative properties, brain white matter (WM is vulnerable to the oxidative stress. This study is conducted to examine possible relationships by using a hypothesis-driven mediation model. Methods. Twenty-nine patients with PD and 26 healthy controls participated in this study, with complete examinations of cardiac autonomic parameters, plasma DNA level, and WM integrity. A single-level three-variable mediation model was used to investigate the possible relationships. Results. The elevated serum oxidative stress biomarkers include plasma nuclear DNA and mitochondrial DNA, and poorer cardiac autonomic parameters and multiple regional microstructural WM changes are demonstrated. Further mediation analysis shows that plasma nuclear DNA served as the mediators between poorer baroreflex sensitivity and mean diffusivity changes in cingulum. Conclusions. These results provide a possible pathophysiology for how the poor baroreflex sensitivity and higher oxidative stress adversely impacted the WM integrity. This model could provide us with a piece of the puzzle of the entire PD pathogenesis.

Autonomic cardiac regulation and morpho-physiological responses to eight week training preparation in junior soccer players

Directory of Open Access Journals (Sweden)

Michal Botek

2014-09-01

Full Text Available Background: Training preparation in soccer is thought to improve body composition and performance level, especially the maximal aerobic capacity (VO2max. However, an enhancement in performance may be attenuated by the increase of fatigue. Heart rate variability (HRV as a non-invasive index of autonomic nervous system (ANS activity has been considered to be a sensitive tool in fatigue assessment. Objective: This study was focused to evaluate the response of ANS activity and morpho-physiological parameters to eight week training preparation. Methods: Study included 12 trained soccer players aged 17.2 ± 1.2 years. Athletes underwent pre- and post-preparation testing that included the ANS activity assessment by spectral analysis of HRV in supine and upright position. Further, body composition was analyzed via electrical bio-impedance method and physiological parameters were assessed during maximal stress tests. ANS activity and subjective feeling of fatigue was assessed continuously within subsequent weeks of preparation. Results: No significant differences in all HRV variables within weeks were found. Pre vs. post analyses revealed a significant (p < .05 increase in body weight, fat free mass, body mass index, and peak power. A significant decline in mean maximal heart rate (HR and resting HR at standing was identified at the end of preparation. Since no significant changes between pre- post-preparation in the mean VO2max occurred, the positive correlation between the individual change in VO2max and the vagally related HRV [supine LnHF (r = .78, Ln rMSSD (r = .63, and the standing LnHF (r = .73, p < .05] was found. Conclusions: This study showed that an 8 week training program modified particularly fat free mass and short-term endurance, whereas both the autonomic cardiac regulation and the feeling of fatigue remained almost unaffected. Standing position seems to be more sensitive in terms of the HR response in relation to fatigue

Delayed autonomic neuropathy in a patient with diethylene glycol poisoning: a case report.

Science.gov (United States)

Kamada, Hiroki; Suzuki, Hideaki; Yamamoto, Saori; Nomura, Ryosuke; Kushimoto, Shigeki

2017-07-01

A 72-year-old man presented to our hospital after ingesting insecticide containing approximately 2 mL/kg diethylene glycol, which exceeded the lethal dose of 1 mL/kg. The patient recovered from critical symptoms on acute phase until day 3, but received artificial ventilation for muscle weakness secondary to sensorimotor neuropathy on days 11-54. Even after marked improvement from sensorimotor neuropathy, the patient continued to complain of orthostatic hypotension. Autonomic neuropathy was identified by positive result of a head-up tilt test, and reduction in coefficient of variation of R-R intervals and cardiac iodine-123-metaiodobenzylguanidine uptake for the assessment of cardiac sympathetic activity. The patient's symptoms fully recovered 2 years after the exposure to diethylene glycol. This case shows the first report of delayed autonomic neuropathy after recovery from severe sensorimotor neuropathy, and suggests the importance of continuous monitoring for late-onset neurological complications.

Cardiac vagal control and theoretical models of co-occurring depression and anxiety: A cross-sectional psychophysiological study of community elderly

Directory of Open Access Journals (Sweden)

Chen Hsi-Chung

2012-07-01

Full Text Available Abstract Background In order to elucidate the complex relationship between co-occurring depression and anxiety with cardiac autonomic function in the elderly, this study examined the correlation between cardiac vagal control (CVC and pre-defined, theoretical factors from the Hospital Anxiety and Depression Scale (HADS. Methods Three hundred fifty-four randomly selected Chinese male subjects aged ≥65 years and living in the community were enrolled. CVC was measured using a frequency-domain index of heart rate variability. Results Confirmatory factor analysis showed that the flat tripartite model of HADS provided a modest advantage in model fit when compared with other theoretical factor solutions. In the flat tripartite model, there was a significant negative association between anhedonic depression and CVC. In contrast, autonomic anxiety showed a significant positive correlation with CVC. In the hierarchical tripartite model, negative affectivity was not directly associated with CVC; instead, it had positive and negative indirect effects on CVC via autonomic anxiety and anhedonic depression, respectively. As scores for negative affectivity increased, these specific indirect effects diminished. Conclusions Among competing models of co-occurring depression and anxiety, constructs from tripartite models demonstrate fair conformity with the data but unique and distinct correlations with CVC. Negative affectivity may determine the relationship of anhedonic depression and autonomic anxiety with CVC. Separating affective symptoms under the constructs of the tripartite models helps disentangle complex associations between co-occurring depression and anxiety with CVC.

Effect of maturation on hemodynamic and autonomic control recovery following maximal running exercise in highly-trained young soccer players

Directory of Open Access Journals (Sweden)

Martin eBuchheit

2011-10-01

Full Text Available The purpose of this study was to examine the effect of maturation on post-exercise hemodynamic and autonomic responses. Fifty-five highly-trained young male soccer players (12-18 yr classified as pre-, circum- or post-peak height velocity (PHV performed a graded running test to exhaustion on a treadmill. Before (Pre and after (5th-10th min, Post exercise, heart rate (HR, stroke volume (SV, cardiac ouput (CO, arterial pressure (AP and total peripheral resistance (TPR were monitored. Parasympathetic (high-frequency [HFRR] of HR variability (HRV and baroreflex sensitivity [Ln BRS] and sympathetic activity (low-frequency [LFSAP] of systolic AP variability were estimated. Post-exercise blood lactate [La]b, the HR recovery (HRR time constant and parasympathetic reactivation (time varying HRV analysis were assessed. In all three groups, exercise resulted in increased HR, CO, AP and LFSAP (P<0.001, decreased SV, HFRR and Ln BRS (all P<0.001, and no change in TPRI (P=0.98. There was no ‘maturation x time’ interaction for any of the hemodynamic or autonomic variables (all P>0.22. After exercise, pre-PHV players displayed lower SV, CO and [La]b, faster HRR and greater parasympathetic reactivation compared with circum- and post-PHV players. Multiple regression analysis showed that lean muscle mass, [La]b and Pre parasympathetic activity were the strongest predictors of HRR (r2=0.62, P<0.001. While pre-PHV players displayed a faster HRR and greater post-exercise parasympathetic reactivation, maturation had little influence on the hemodynamic and autonomic responses following maximal running exercise. HRR relates to lean muscle mass, blood acidosis and intrinsic parasympathetic function, with less evident impact of post-exercise autonomic function.

Relationship between cardiac output and effective renal plasma flow in patients with cardiac disease

Energy Technology Data Exchange (ETDEWEB)

McGriffin, D; Tauxe, W N; Lewis, C; Karp, R; Mantle, J

1984-12-01

The relationship between effective renal plasma flow (ERPF) and cardiac output was examined in 46 patients (22 with congestive heart failure and 24 following cardiac surgical procedures) by simultaneously measuring the global ERPF by the single-injection method and cardiac output by the thermodilution method. Of the patients in the heart-failure group, 21 also had pulmonary artery end diastolic pressure (PAEDP) recorded at the same time. ERPF and cardiac output were found to be related by the regression equations: cardiac output = 2.08 + 0.0065 ERPF (r, 080), with a SE of estimate of 0.81 l/min. ERPF and PAEDP were related by the regression equation: PAEDP = 42.02 - 0.0675 ERPF (r, 0.86), with a SE of estimate of 5.5 mm Hg. ERPF may be a useful noninvasive method of estimating cardiac output if it is known that no intrinsic kidney disease is present, and if the error of 0.81 l/min (1 SE of estimate) is within the range of clinical usefulness. The error is principally attributable to the determination of cardiac output by the thermodilution method.

Hyperglycemia can delay left ventricular dysfunction but not autonomic damage after myocardial infarction in rodents

Directory of Open Access Journals (Sweden)

Brum Patricia C

2011-04-01

Full Text Available Abstract Background Although clinical diabetes mellitus is obviously a high risk factor for myocardial infarction (MI, in experimental studies disagreement exists about the sensitivity to ischemic injury of an infarcted myocardium. Recently, our group demonstrated that diabetic animals presented better cardiac function recovery and cellular resistance to ischemic injury than nondiabetics. In the present study, we evaluated the chronic effects of MI on left ventricular (LV and autonomic functions in streptozotocin (STZ diabetic rats. Methods Male Wistar rats were divided into 4 groups: control (C, n = 15, diabetes (D, n = 16, MI (I, n = 21, and diabetes + MI (DI, n = 30. MI was induced 15 days after diabetes (STZ induction. Ninety days after MI, LV and autonomic functions were evaluated (8 animals each group. Left ventricular homogenates were analyzed by Western blotting to evaluate the expression of calcium handling proteins. Results MI area was similar in infarcted groups (~43%. Ejection fraction and +dP/dt were reduced in I compared with DI. End-diastolic pressure was additionally increased in I compared with DI. Compared with DI, I had increased Na+-Ca2+ exchange and phospholamban expression (164% and decreased phosphorylated phospholamban at serine16 (65% and threonine17 (70% expression. Nevertheless, diabetic groups had greater autonomic dysfunction, observed by baroreflex sensitivity and pulse interval variability reductions. Consequently, the mortality rate was increased in DI compared with I, D, and C groups. Conclusions LV dysfunction in diabetic animals was attenuated after 90 days of myocardial infarction and was associated with a better profile of calcium handling proteins. However, this positive adaptation was not able to reduce the mortality rate of DI animals, suggesting that autonomic dysfunction is associated with increased mortality in this group. Therefore, it is possible that the better cardiac function has been transitory

Positive effect of combined exercise training in a model of metabolic syndrome and menopause: autonomic, inflammatory, and oxidative stress evaluations.

Science.gov (United States)

Conti, Filipe Fernandes; Brito, Janaina de Oliveira; Bernardes, Nathalia; Dias, Danielle da Silva; Malfitano, Christiane; Morris, Mariana; Llesuy, Susana Francisca; Irigoyen, Maria-Cláudia; De Angelis, Kátia

2015-12-15

It is now well established that after menopause cardiometabolic disorders become more common. Recently, resistance exercise has been recommended as a complement to aerobic (combined training, CT) for the treatment of cardiometabolic diseases. The aim of this study was to evaluate the effects of CT in hypertensive ovariectomized rats undergoing fructose overload in blood pressure variability (BPV), inflammation, and oxidative stress parameters. Female rats were divided into the following groups (n = 8/group): sedentary normotensive Wistar rats (C), and sedentary (FHO) or trained (FHOT) ovariectomized spontaneously hypertensive rats undergoing and fructose overload. CT was performed on a treadmill and ladder adapted to rats in alternate days (8 wk; 40-60% maximal capacity). Arterial pressure (AP) was directly measured. Oxidative stress and inflammation were measured on cardiac and renal tissues. The association of risk factors (hypertension + ovariectomy + fructose) promoted increase in insulin resistance, mean AP (FHO: 174 ± 4 vs. C: 108 ± 1 mmHg), heart rate (FHO: 403 ± 12 vs. C: 352 ± 11 beats/min), BPV, cardiac inflammation (tumor necrosis factor-α-FHO: 65.8 ± 9.9 vs. C: 23.3 ± 4.3 pg/mg protein), and oxidative stress cardiac and renal tissues. However, CT was able to reduce mean AP (FHOT: 158 ± 4 mmHg), heart rate (FHOT: 303 ± 5 beats/min), insulin resistance, and sympathetic modulation. Moreover, the trained rats presented increased nitric oxide bioavailability, reduced tumor necrosis factor-α (FHOT: 33.1 ± 4.9 pg/mg protein), increased IL-10 in cardiac tissue and reduced lipoperoxidation, and increased antioxidant defenses in cardiac and renal tissues. In conclusion, the association of risk factors promoted an additional impairment in metabolic, cardiovascular, autonomic, inflammatory, and oxidative stress parameters and combined exercise training was able to attenuate these dysfunctions. Copyright © 2015 the American Physiological Society.

Morphology of subcortical brain nuclei is associated with autonomic function in healthy humans.

Science.gov (United States)

Ruffle, James K; Coen, Steven J; Giampietro, Vincent; Williams, Steven C R; Apkarian, A Vania; Farmer, Adam D; Aziz, Qasim

2018-01-01

The autonomic nervous system (ANS) is a brain body interface which serves to maintain homeostasis by influencing a plethora of physiological processes, including metabolism, cardiorespiratory regulation and nociception. Accumulating evidence suggests that ANS function is disturbed in numerous prevalent clinical disorders, including irritable bowel syndrome and fibromyalgia. While the brain is a central hub for regulating autonomic function, the association between resting autonomic activity and subcortical morphology has not been comprehensively studied and thus was our aim. In 27 healthy subjects [14 male and 13 female; mean age 30 years (range 22-53 years)], we quantified resting ANS function using validated indices of cardiac sympathetic index (CSI) and parasympathetic cardiac vagal tone (CVT). High resolution structural magnetic resonance imaging scans were acquired, and differences in subcortical nuclei shape, that is, 'deformation', contingent on resting ANS activity were investigated. CSI positively correlated with outward deformation of the brainstem, right nucleus accumbens, right amygdala and bilateral pallidum (all thresholded to corrected P right amygdala and pallidum (all thresholded to corrected P Left and right putamen volume positively correlated with CVT (r = 0.62, P = 0.0047 and r = 0.59, P = 0.008, respectively), as did the brainstem (r = 0.46, P = 0.049). These data provide novel evidence that resting autonomic state is associated with differences in the shape and volume of subcortical nuclei. Thus, subcortical morphological brain differences in various disorders may partly be attributable to perturbation in autonomic function. Further work is warranted to investigate these findings in clinical populations. Hum Brain Mapp 39:381-392, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Cardiac Concomitants of Feedback and Prediction Error Processing in Reinforcement Learning

Science.gov (United States)

Kastner, Lucas; Kube, Jana; Villringer, Arno; Neumann, Jane

2017-01-01

Successful learning hinges on the evaluation of positive and negative feedback. We assessed differential learning from reward and punishment in a monetary reinforcement learning paradigm, together with cardiac concomitants of positive and negative feedback processing. On the behavioral level, learning from reward resulted in more advantageous behavior than learning from punishment, suggesting a differential impact of reward and punishment on successful feedback-based learning. On the autonomic level, learning and feedback processing were closely mirrored by phasic cardiac responses on a trial-by-trial basis: (1) Negative feedback was accompanied by faster and prolonged heart rate deceleration compared to positive feedback. (2) Cardiac responses shifted from feedback presentation at the beginning of learning to stimulus presentation later on. (3) Most importantly, the strength of phasic cardiac responses to the presentation of feedback correlated with the strength of prediction error signals that alert the learner to the necessity for behavioral adaptation. Considering participants' weight status and gender revealed obesity-related deficits in learning to avoid negative consequences and less consistent behavioral adaptation in women compared to men. In sum, our results provide strong new evidence for the notion that during learning phasic cardiac responses reflect an internal value and feedback monitoring system that is sensitive to the violation of performance-based expectations. Moreover, inter-individual differences in weight status and gender may affect both behavioral and autonomic responses in reinforcement-based learning. PMID:29163004

Cardiac Concomitants of Feedback and Prediction Error Processing in Reinforcement Learning

Directory of Open Access Journals (Sweden)

Lucas Kastner

2017-10-01

Full Text Available Successful learning hinges on the evaluation of positive and negative feedback. We assessed differential learning from reward and punishment in a monetary reinforcement learning paradigm, together with cardiac concomitants of positive and negative feedback processing. On the behavioral level, learning from reward resulted in more advantageous behavior than learning from punishment, suggesting a differential impact of reward and punishment on successful feedback-based learning. On the autonomic level, learning and feedback processing were closely mirrored by phasic cardiac responses on a trial-by-trial basis: (1 Negative feedback was accompanied by faster and prolonged heart rate deceleration compared to positive feedback. (2 Cardiac responses shifted from feedback presentation at the beginning of learning to stimulus presentation later on. (3 Most importantly, the strength of phasic cardiac responses to the presentation of feedback correlated with the strength of prediction error signals that alert the learner to the necessity for behavioral adaptation. Considering participants' weight status and gender revealed obesity-related deficits in learning to avoid negative consequences and less consistent behavioral adaptation in women compared to men. In sum, our results provide strong new evidence for the notion that during learning phasic cardiac responses reflect an internal value and feedback monitoring system that is sensitive to the violation of performance-based expectations. Moreover, inter-individual differences in weight status and gender may affect both behavioral and autonomic responses in reinforcement-based learning.

Exercise-induced ventricular arrhythmias and vagal dysfunction in Chagas disease patients with no apparent cardiac involvement

Directory of Open Access Journals (Sweden)

Henrique Silveira Costa

2015-04-01

Full Text Available INTRODUCTION : Exercise-induced ventricular arrhythmia (EIVA and autonomic imbalance are considered as early markers of heart disease in Chagas disease (ChD patients. The objective of the present study was to verify the differences in the occurrence of EIVA and autonomic maneuver indexes between healthy individuals and ChD patients with no apparent cardiac involvement. METHODS : A total of 75 ChD patients with no apparent cardiac involvement, aged 44.7 (8.5 years, and 38 healthy individuals, aged 44.0 (9.2 years, were evaluated using echocardiography, symptom-limited treadmill exercise testing and autonomic function tests. RESULTS : The occurrence of EIVA was higher in the chagasic group (48% than in the control group (23.7% during both the effort and the recovery phases. Frequent ventricular contractions occurred only in the patient group. Additionally, the respiratory sinus arrhythmia index was significantly lower in the chagasic individuals compared with the control group. CONCLUSIONS : ChD patients with no apparent cardiac involvement had a higher frequency of EIVA as well as more vagal dysfunction by respiratory sinus arrhythmia. These results suggest that even when asymptomatic, ChD patients possess important arrhythmogenic substrates and subclinical disease.

Hemodynamic, morphometric and autonomic patterns in hypertensive rats - renin-angiotensin system modulation

Directory of Open Access Journals (Sweden)

Fernanda S. Zamo

2010-01-01

Full Text Available BACKGROUND: Spontaneously hypertensive rats develop left ventricular hypertrophy, increased blood pressure and blood pressure variability, which are important determinants of heart damage, like the activation of renin-angiotensin system. AIMS: To investigate the effects of the time-course of hypertension over 1 hemodynamic and autonomic patterns (blood pressure; blood pressure variability; heart rate; 2 left ventricular hypertrophy; and 3 local and systemic Renin-angiotensin system of the spontaneously hypertensive rats. METHODS: Male spontaneously hypertensive rats were randomized into two groups: young (n=13 and adult (n=12. Hemodynamic signals (blood pressure, heart rate, blood pressure variability (BPV and spectral analysis of the autonomic components of blood pressure were analyzed. LEFT ventricular hypertrophy was measured by the ratio of LV mass to body weight (mg/g, by myocyte diameter (μm and by relative fibrosis area (RFA, %. ACE and ACE2 activities were measured by fluorometry (UF/min, and plasma renin activity (PRA was assessed by a radioimmunoassay (ng/mL/h. Cardiac gene expressions of Agt, Ace and Ace2 were quantified by RT-PCR (AU. RESULTS: The time-course of hypertension in spontaneously hypertensive rats increased BPV and reduced the alpha index in adult spontaneously hypertensive rats. Adult rats showed increases in left ventricular hypertrophy and in RFA. Compared to young spontaneously hypertensive rats, adult spontaneously hypertensive rats had lower cardiac ACE and ACE2 activities, and high levels of PRA. No change was observed in gene expression of Renin-angiotensin system components. CONCLUSIONS: The observed autonomic dysfunction and modulation of Renin-angiotensin system activity are contributing factors to end-organ damage in hypertension and could be interacting. Our findings suggest that the management of hypertensive disease must start before blood pressure reaches the highest stable levels and the consequent

Academic self-concept, autonomous academic motivation, and academic achievement : mediating and additive effects

OpenAIRE

Guay, Frédéric; Ratelle, Catherine; Roy, Amélie; Litalien, David

2010-01-01

Three conceptual models were tested to examine the relationships among academic self-concept, autonomous academic motivation, and academic achievement. This allowed us to determine whether 1) autonomous academic motivation mediates the relation between academic self-concept and achievement, 2) academic self-concept mediates the relation between autonomous academic motivation and achievement, or 3) both motivational constructs have an additive effect on academic achievement. A total of 925 hig...

Autonomous Mower vs. Rotary Mower: Effects on Turf Quality and Weed Control in Tall Fescue Lawn

OpenAIRE

Michel Pirchio; Marco Fontanelli; Christian Frasconi; Luisa Martelloni; Michele Raffaelli; Andrea Peruzzi; Monica Gaetani; Simone Magni; Lisa Caturegli; Marco Volterrani; Nicola Grossi

2018-01-01

Autonomous mowers are battery-powered machines designed for lawn mowing that require very low human labour. Autonomous mowers can increase turf quality and reduce local noise and pollution compared with gasoline-powered rotary mowers. However, very little is known about the effects of autonomous mowing on encroaching weeds. The aim of this research was to compare the effects of an autonomous mower and an ordinary gasoline-powered mower on weed development in an artificially infested tall fesc...

Functional Imaging of Autonomic Regulation: Methods and Key Findings

Directory of Open Access Journals (Sweden)

Paul M Macey

2016-01-01

brain regions mediating postural and motoric actions, including respiration and cardiac output. The study of pathological processes associated with autonomic disruption shows susceptibilities of different brain structures to altered timing of neural function, notably in sleep disordered breathing, such as obstructive sleep apnea and congenital central hypoventilation syndrome. The cerebellum, in particular, serves coordination roles for vestibular stimuli and blood pressure changes, and shows both injury and substantially altered timing of responses to pressor challenges in sleep-disordered breathing conditions. The insights into central autonomic processing provided by

Assessment of Autonomic Function by Phase Rectification of RRInterval Histogram Analysis in Chagas Disease

Directory of Open Access Journals (Sweden)

Olivassé Nasari Junior

2015-06-01

Full Text Available Background: In chronic Chagas disease (ChD, impairment of cardiac autonomic function bears prognostic implications. Phase‑rectification of RR-interval series isolates the sympathetic, acceleration phase (AC and parasympathetic, deceleration phase (DC influences on cardiac autonomic modulation. Objective: This study investigated heart rate variability (HRV as a function of RR-interval to assess autonomic function in healthy and ChD subjects. Methods: Control (n = 20 and ChD (n = 20 groups were studied. All underwent 60-min head-up tilt table test under ECG recording. Histogram of RR-interval series was calculated, with 100 ms class, ranging from 600–1100 ms. In each class, mean RR-intervals (MNN and root-mean-squared difference (RMSNN of consecutive normal RR-intervals that suited a particular class were calculated. Average of all RMSNN values in each class was analyzed as function of MNN, in the whole series (RMSNNT, and in AC (RMSNNAC and DC (RMSNNDC phases. Slopes of linear regression lines were compared between groups using Student t-test. Correlation coefficients were tested before comparisons. RMSNN was log-transformed. (α < 0.05. Results: Correlation coefficient was significant in all regressions (p < 0.05. In the control group, RMSNNT, RMSNNAC, and RMSNNDC significantly increased linearly with MNN (p < 0.05. In ChD, only RMSNNAC showed significant increase as a function of MNN, whereas RMSNNT and RMSNNDC did not. Conclusion: HRV increases in proportion with the RR-interval in healthy subjects. This behavior is lost in ChD, particularly in the DC phase, indicating cardiac vagal incompetence.

Distinct subsets of Eve-positive pericardial cells stabilise cardiac outflow and contribute to Hox gene-triggered heart morphogenesis in Drosophila.

Science.gov (United States)

Zmojdzian, Monika; de Joussineau, Svetlana; Da Ponte, Jean Philippe; Jagla, Krzysztof

2018-01-17

The Drosophila heart, composed of discrete subsets of cardioblasts and pericardial cells, undergoes Hox-triggered anterior-posterior morphogenesis, leading to a functional subdivision into heart proper and aorta, with its most anterior part forming a funnel-shaped cardiac outflow. Cardioblasts differentiate into Tin-positive 'working myocytes' and Svp-expressing ostial cells. However, developmental fates and functions of heart-associated pericardial cells remain elusive. Here, we show that the pericardial cells that express the transcription factor Even Skipped adopt distinct fates along the anterior-posterior axis. Among them, the most anterior Antp-Ubx-AbdA - negative cells form a novel cardiac outflow component we call the outflow hanging structure, whereas the Antp-expressing cells differentiate into wing heart precursors. Interestingly, Hox gene expression in the Even Skipped-positive cells not only underlies their antero-posterior diversification, but also influences heart morphogenesis in a non-cell-autonomous way. In brief, we identify a new cardiac outflow component derived from a subset of Even Skipped-expressing cells that stabilises the anterior heart tip, and demonstrate non-cell-autonomous effects of Hox gene expression in the Even Skipped-positive cells on heart morphogenesis. © 2018. Published by The Company of Biologists Ltd.

Mechanisms Regulating the Cardiac Output Response to Cyanide Infusion, a Model of Hypoxia

Science.gov (United States)

Liang, Chang-seng; Huckabee, William E.

1973-01-01

When tissue metabolic changes like those of hypoxia were induced by intra-aortic infusion of cyanide in dogs, cardiac output began to increase after 3 to 5 min, reached a peak (220% of the control value) at 15 min, and returned to control in 40 min. This pattern of cardiac output rise was not altered by vagotomy with or without atropine pretreatment. However, this cardiac output response could be differentiated into three phases by pretreating the animals with agents that block specific activities of the sympatho-adrenal system. First, ganglionic blockade produced by mecamylamine or sympathetic nerve blockade by bretylium abolished the middle phase of the cardiac output seen in the untreated animal, but early and late phases still could be discerned. Second, beta-adrenergic receptor blockade produced by propranolol shortened the total duration of the cardiac output rise by abolishing the late phase. Third, when given together, propranolol and mecamylamine (or bretylium) prevented most of the cardiac output rise that follows the early phase. When cyanide was given to splenectomized dogs, the duration of the cardiac output response was not shortened, but the response became biphasic, resembling that seen after chemical sympathectomy. A similar biphasic response of the cardiac output also resulted from splenic denervation; sham operation or nephrectomy had no effect on the monophasic pattern of the normal response. Splenic venous blood obtained from cyanide-treated dogs, when infused intraportally, caused an increase in cardiac output in recipient dogs; similar infusion of arterial blood had no effects. These results suggest that the cardiac output response to cyanide infusion consists of three components: an early phase, related neither to the autonomic nervous system nor to circulating catecholamines; a middle phase, caused by a nonadrenergic humoral substance released from the spleen by sympathetic stimulation; and a late phase, dependent upon adrenergic receptors

Differential cardiac effects in rats exposed to atmospheric ...

Science.gov (United States)

The results of this study demonstrate that atmospheric smog generated from both isoprene and toluene cause cardiac effects in rats. In addition, it appears that smog from toluene is more toxic in terms of cardiac arrhythmogenicity. Smog, which is a complex mixture of particulate matter and gaseous irritants (ozone, sulfur dioxide, reactive aldehydes), as well as components which react with sunlight to form secondary pollutants, has recently been linked to increased risk of adverse cardiac responses. The components, and therefore health effects, of atmospheric smog are determined by the fuel used to generate them. In this study we examined the difference between isoprene- and toluene-generated smog in causing cardiac effects in rats and hypothesized that both atmospheres would cause cardiac electrical and functional changes in rats. Male Wistar-Kyoto rats were exposed to either atmospheric smog generated by the USEPA’s mobile reaction chamber using either isoprene or toluene, or filtered air for four hours. One day later, rats were anesthetized and left ventricular functional responses to dobutamine were measured using a Millar probe and arrhythmia sensitivity to aconitine. Baseline left ventricular pressure (LVP) was lower in toluene-exposed animals but not isoprene when compared to air. Increases in LVP with increasing doses of dobutamine were impaired only in toluene-exposed rats. Both isoprene and toluene impaired the rate of ventri

Exploring relationships for visceral and somatic pain with autonomic control and personality.

Science.gov (United States)

Paine, Peter; Kishor, Jessin; Worthen, Sian F; Gregory, Lloyd J; Aziz, Qasim

2009-08-01

The autonomic nervous system (ANS) integrates afferent and motor activity for homeostatic processes including pain. The aim of the study was to compare hitherto poorly characterised relations between brainstem autonomic control and personality in response to visceral and somatic pain. Eighteen healthy subjects (16 females, mean age 34) had recordings during rest and pain of heart rate (HR), cardiac vagal tone (CVT), cardiac sensitivity to baroreflex (CSB), skin conductance level (SC), cardiac sympathetic index (CSI) and mean blood pressure (MBP). Visceral pain was induced by balloon distension in proximal (PB) and distal (DB) oesophagus and somatic pain by nail-bed pressure (NBP). Eight painful stimuli were delivered at each site and unpleasantness and intensity measured. Personality was profiled with the Big Five inventory. (1) Oesophageal intubation evoked "fight-flight" responses: HR and sympathetic (CSI, SC, MBP) elevation with parasympathetic (CVT) withdrawal (pintrovert subjects had greater positive pain-related CVT slope change (neuroticism r 0.8, p<0.05; extroversion r -0.5, p<0.05). Pain-evoked heart rate increases were mediated by parasympathetic and sympathetic co-activation - a novel finding in humans but recently described in mammals too. Visceral pain-related parasympathetic change correlated with personality. ANS defence responses are nuanced and may relate to personality type for visceral pain. Clinical relevance of these findings warrants further exploration.

Autonomic and metabolic effects of OSA in childhood obesity.

Science.gov (United States)

Oliveira, F M; Tran, W H; Lesser, D; Bhatia, R; Ortega, R; Mittelman, S D; Keens, T G; Davidson Ward, S L; Khoo, M C

2010-01-01

This study investigates the effects of exposure to intermittent hypoxia on cardiovascular autonomic control and metabolic function in obese children with obstructive sleep apnea (OSA). Each subject underwent: (1) a polysomnography; (2) morning fasting blood samples and a subsequent FSIVGTT; (3) noninvasive measurement of respiration, arterial blood pressure, and heart rate during supine and standing postures. Assessment of adiposity was performed using a DEXA scan. From these measurements, we deduced the pertinent sleep parameters, Bergman minimal model parameters and the parameters characterizing a minimal model of cardiovascular variability. Results suggest that intermittent hypoxia in OSA contributes independently to insulin resistance and autonomic dysfunction in overweight children.

Role of autogenic relaxation in management of diabetic cardiovascular autonomic neuropathy in type II diabetes mellitus patients

OpenAIRE

Manish K. Verma; D. A. Biswas; Shambhavi Tripathi; N. S. Verma

2016-01-01

Background: Cardiac autonomic neuropathy (CAN) is a very common complication of Type II diabetes mellitus patients. Early detection and treatment of CAN is necessary for reduction of mortality and morbidity in type II diabetes patients. Methods: The study included 120 diagnosed cases of type 2 diabetes mellitus with autonomic neuropathy both male and female, with more than 5 years duration of disease. Age group of the study subjects was between 30 and ndash; 70 years. All the 120 diabet...

Effects of insula resection on autonomic nervous system activity

NARCIS (Netherlands)

de Morree, Helma; Rutten, Geert-Jan; Szabo, B.M.; Sitskoorn, Margriet; Kop, Wijo

2016-01-01

Background: The insula is an essential component of the central autonomic network and plays a critical role in autonomic regulation in response to environmental stressors. The role of the insula in human autonomic regulation has been primarily investigated following cerebrovascular accidents, but

Cardiovascular autonomic dysfunction and carotid stiffness in adults with repaired tetralogy of Fallot.

Science.gov (United States)

Novaković, Marko; Prokšelj, Katja; Starc, Vito; Jug, Borut

2017-06-01

Adults after surgical repair of tetralogy of Fallot (ToF) may have impaired vascular and cardiac autonomic function. Thus, we wanted to assess interrelations between heart rate variability (HRV) and heart rate recovery (HRR), as parameters of cardiac autonomic function, and arterial stiffness, as a parameter of vascular function, in adults with repaired ToF as compared to healthy controls. In a case-control study of adults with repaired ToF and healthy age-matched controls we measured: 5-min HRV variability (with time and frequency domain data collected), carotid artery stiffness (through pulse-wave analysis using echo-tracking ultrasound) and post-exercise HRR (cycle ergometer exercise testing). Twenty-five patients with repaired ToF (mean age 38 ± 10 years) and 10 healthy controls (mean age 39 ± 8 years) were included. Selected HRR and HRV (time-domain) parameters, but not arterial stiffness were significantly reduced in adults after ToF repair. Moreover, a strong association between late/slow HRR (after 2, 3 and 4 min) and carotid artery stiffness was detected in ToF patients (r = -0.404, p = 0.045; r = -0.545, p = 0.005 and r = -0.545, p = 0.005, respectively), with statistical significance retained even after adjusting for age, gender, resting heart rate and β-blockers use (r = -0.393, p = 0.024 for HRR after 3 min). Autonomic cardiac function is impaired in patients with repaired ToF, and independently associated with vascular function in adults after ToF repair, but not in age-matched healthy controls. These results might help in introducing new predictors of cardiovascular morbidity in a growing population of adults after surgical repair of ToF.

Cardiac rehabilitation: an effective secondary prevention intervention.

Science.gov (United States)

Milligan, Fiona

A combination of quantitative and qualitative research was used to determine the effectiveness of a cardiac rehabilitation (CR) programme in a cohort of patients referred to the service at a London hospital. Quantitative data analysis provided evidence of effectiveness of participation in CR in reduced hospital readmission rates and use of recognised pharmacological management strategies. Self-reported physical activity levels and quality of life (QOL) in individuals who participated in the cardiac rehabilitation programme were qualitatively measured with questionnaires. Results provided evidence of benefit in continued participation in exercise. However, there was no evidence of benefit to QOL status post participation at 1 year. A p-value of 0.001 provided significant statistical evidence supporting the hypothesis of benefit in continued participation in exercise in participants following attendance at a cardiac rehabilitation programme. QOL status; a statistically significant p-value of 0.001 rejected the hypothesis (H1) of benefit. This would imply that participation CR programmes does not appear to provide sustained benefits in QOL. A number of moderating variables were suggested as explaining the finding such as homogeneity of respondents, age, mood bias and the timeframe of 1 year between participation in rehabilitation and self-reporting. CR appears to be an effective but time-limited intervention in relation to improvements in QOL. Collaborative working partnerships between specialist interventions, such as CR with chronic disease management strategies may provide greater sustainability of benefits gained from participation in cardiac rehabilitation programmes.

Enhancing Predictive Accuracy of Cardiac Autonomic Neuropathy Using Blood Biochemistry Features and Iterative Multitier Ensembles.

Science.gov (United States)

Abawajy, Jemal; Kelarev, Andrei; Chowdhury, Morshed U; Jelinek, Herbert F

2016-01-01

Blood biochemistry attributes form an important class of tests, routinely collected several times per year for many patients with diabetes. The objective of this study is to investigate the role of blood biochemistry for improving the predictive accuracy of the diagnosis of cardiac autonomic neuropathy (CAN) progression. Blood biochemistry contributes to CAN, and so it is a causative factor that can provide additional power for the diagnosis of CAN especially in the absence of a complete set of Ewing tests. We introduce automated iterative multitier ensembles (AIME) and investigate their performance in comparison to base classifiers and standard ensemble classifiers for blood biochemistry attributes. AIME incorporate diverse ensembles into several tiers simultaneously and combine them into one automatically generated integrated system so that one ensemble acts as an integral part of another ensemble. We carried out extensive experimental analysis using large datasets from the diabetes screening research initiative (DiScRi) project. The results of our experiments show that several blood biochemistry attributes can be used to supplement the Ewing battery for the detection of CAN in situations where one or more of the Ewing tests cannot be completed because of the individual difficulties faced by each patient in performing the tests. The results show that AIME provide higher accuracy as a multitier CAN classification paradigm. The best predictive accuracy of 99.57% has been obtained by the AIME combining decorate on top tier with bagging on middle tier based on random forest. Practitioners can use these findings to increase the accuracy of CAN diagnosis.

Analysis of cardiac autonomic modulation of children with attention deficit hyperactivity disorder

Directory of Open Access Journals (Sweden)

de Carvalho TD

2014-04-01

Full Text Available Tatiana Dias de Carvalho,1,2 Rubens Wajnsztejn,3 Luiz Carlos de Abreu,2,7 Luiz Carlos Marques Vanderlei,4 Moacir Fernandes Godoy,5 Fernando Adami,2 Vitor E Valenti,6 Carlos B M Monteiro,2,7 Claudio Leone,7 Karen Cristina da Cruz Martins,2 Celso Ferreira11Departamento de Medicina, Disciplina de Cardiologia, Universidade Federal de São Paulo, UNIFESP, São Paulo, Brazil; 2Laboratório de Escrita Científica da Faculdade de Medicina do ABC, FMABC, Santo André, Brazil; 3Núcleo Especializado em Aprendizagem, Programa de pós-graduação em Ciências da Saúde da Faculdade de Medicina do ABC, FMABC, Santo André, Brazil; 4Departamento de Fisioterapia da Faculdade de Ciências e Tecnologia, Universidade Estadual Paulista, UNESP, Presidente Prudente, São Paulo, Brazil; 5Núcleo Transdisciplinar de Estudos do Caos e da Complexidade. Faculdade de Medicina de São José de Rio Preto, FAMERP, São José do Rio Preto, Brazil; 6Departamento de Fonoaudiologia da Faculdade de Filosofia e Ciências, Universidade Estadual Paulista, UNESP, Marília, Brazil; 7Departamento de Saúde Materno-Infantil da Faculdade de Saúde Pública da Universidade de São Paulo, São Paulo, BrazilBackground: Attention deficit hyperactivity disorder (ADHD is characterized by decreased attention span, impulsiveness, and hyperactivity. Autonomic nervous system imbalance was previously described in this population. We aim to compare the autonomic function of children with ADHD and controls by analyzing heart rate variability (HRV.Methods: Children rested in supine position with spontaneous breathing for 20 minutes. Heart rate was recorded beat by beat. HRV analysis was performed in the time and frequency domains and Poincaré plot.Results: Twenty-eight children with ADHD (22 boys, aged 9.964 years and 28 controls (15 boys, age 9.857 years participated in this study. It was determined that the mean and standard deviation of indexes which indicate parasympathetic activity is higher in

Depression and reduced heart rate variability after cardiac surgery: the mediating role of emotion regulation.

Science.gov (United States)

Patron, Elisabetta; Messerotti Benvenuti, Simone; Favretto, Giuseppe; Gasparotto, Renata; Palomba, Daniela

2014-02-01

Heart rate variability (HRV), as an index of autonomic nervous system (ANS) functioning, is reduced by depression after cardiac surgery, but the underlying mechanisms of this relationship are poorly understood. Poor emotion regulation as a core symptom of depression has also been associated with altered ANS functioning. The present study aimed to examine whether emotion dysregulation could be a mediator of the depression-reduced HRV relationship observed after cardiac surgery. Self-reported emotion regulation and four-minute HRV were measured in 25 depressed and 43 nondepressed patients after cardiac surgery. Mediation analysis was conducted to evaluate emotion regulation as a mediator of the depression-reduced HRV relationship. Compared to nondepressed patients, those with depression showed lower standard deviation of normal-to-normal (NN) intervals (pbehavior partially mediated the effect of depression on LF n.u. and HF n.u. Results confirmed previous findings showing that depression is associated with reduced HRV, especially a reduced vagal tone and a sympathovagal imbalance, after cardiac surgery. This study also provides preliminary evidence that increased trait levels of suppression of emotion-expressive behavior may mediate the depression-related sympathovagal imbalance after cardiac surgery. Copyright © 2013 Elsevier B.V. All rights reserved.

A comparative study of lipid profile and autonomic functions in vegetarian and non-vegetarian postmenopausal women

Directory of Open Access Journals (Sweden)

Arunima Chaudhuri

2013-01-01

Full Text Available Background: The prevalence of dyslipedaemia, autonomic dysfunction leading to cardiovascular diseases, increases with menopause and an ageing population. Autonomic dysfunction as measured by lower heart rate variability is an established risk factor for cardiac death. Diet and nutrition have been extensively investigated as risk factors for major cardiovascular diseases and are also linked to other cardiovascular risk factors. Objectives: To compare lipid profile and autonomic functions of postmenopausal women on vegetarian and non- vegetarian diet. Materials and Methods: 120 Postmenopausal women (menopausal duration and age-matched without any gross systemic disease from an Industrial population were selected. Sixty women were on vegetarian diet and 60 on non-vegetarian diet. BMI and waist/hip ratios were calculated, lipid profile was analyzed, and autonomic function tests were carried out. A comparison was done between the two groups using Students t test. Pearson′s correlation coefficient was calculated between the independent variable (lipid profile parameters and the dependent variables (deep breath test, valsalva ratio, 30:15 ratio, OTT, IHG, CPT to understand the effect of lipid profile on autonomic control of heart. Results : Significant increases in total cholesterol, triglyceride, LDL, cholesterol/HDL ratio were noticed in women on non-vegetarian diet. Results of autonomic function tests, i.e. valsalva ratio, deep breath test, 30: 15R-R intervals ratio, isometric hand grip test, cold pressor test, and orthostatic tolerance test were significantly worsened in postmenopausal women on non-vegetarian diet. Conclusion: Dietary factors may be an important cause of alteration of lipid metabolism. Increased cholesterol decreases heart rate variability and increased LDL cholesterol decreases baroreceptor sensitivity thereby worsening autonomic functions in postmenopausal women.

The role of cardiac vagal tone and inhibitory control in pre-schoolers' listening comprehension.

Science.gov (United States)

Scrimin, Sara; Patron, Elisabetta; Florit, Elena; Palomba, Daniela; Mason, Lucia

2017-12-01

This study investigated the role of basal cardiac activity and inhibitory control at the beginning of the school year in predicting oral comprehension at the end of the year in pre-schoolers. Forty-three, 4-year-olds participated in the study. At the beginning of the school year children's electrocardiogram at rest was registered followed by the assessment of inhibitory control as well as verbal working memory and verbal ability. At the end of the year all children were administered a listening comprehension ability measure. A stepwise regression showed a significant effect of basal cardiac vagal tone in predicting listening comprehension together with inhibitory control and verbal ability. These results are among the first to show the predictive role of basal cardiac vagal tone and inhibitory control in pre-schoolers' oral text comprehension, and offer new insight into the association between autonomic regulation of the heart, inhibitory control, and cognitive activity at a young age. © 2017 Wiley Periodicals, Inc.

Effect of Mindfulness Meditation on Perceived Stress Scores and Autonomic Function Tests of Pregnant Indian Women.

Science.gov (United States)

Muthukrishnan, Shobitha; Jain, Reena; Kohli, Sangeeta; Batra, Swaraj

2016-04-01

Various pregnancy complications like hypertension, preeclampsia have been strongly correlated with maternal stress. One of the connecting links between pregnancy complications and maternal stress is mind-body intervention which can be part of Complementary and Alternative Medicine (CAM). Biologic measures of stress during pregnancy may get reduced by such interventions. To evaluate the effect of Mindfulness meditation on perceived stress scores and autonomic function tests of pregnant Indian women. Pregnant Indian women of 12 weeks gestation were randomised to two treatment groups: Test group with Mindfulness meditation and control group with their usual obstetric care. The effect of Mindfulness meditation on perceived stress scores and cardiac sympathetic functions and parasympathetic functions (Heart rate variation with respiration, lying to standing ratio, standing to lying ratio and respiratory rate) were evaluated on pregnant Indian women. There was a significant decrease in perceived stress scores, a significant decrease of blood pressure response to cold pressor test and a significant increase in heart rate variability in the test group (pwomen. The results of this study suggest that mindfulness meditation improves parasympathetic functions in pregnant women and is a powerful modulator of the sympathetic nervous system during pregnancy.

Network interactions within the canine intrinsic cardiac nervous system: implications for reflex control of regional cardiac function

Science.gov (United States)

Beaumont, Eric; Salavatian, Siamak; Southerland, E Marie; Vinet, Alain; Jacquemet, Vincent; Armour, J Andrew; Ardell, Jeffrey L

2013-01-01

The aims of the study were to determine how aggregates of intrinsic cardiac (IC) neurons transduce the cardiovascular milieu versus responding to changes in central neuronal drive and to determine IC network interactions subsequent to induced neural imbalances in the genesis of atrial fibrillation (AF). Activity from multiple IC neurons in the right atrial ganglionated plexus was recorded in eight anaesthetized canines using a 16-channel linear microelectrode array. Induced changes in IC neuronal activity were evaluated in response to: (1) focal cardiac mechanical distortion; (2) electrical activation of cervical vagi or stellate ganglia; (3) occlusion of the inferior vena cava or thoracic aorta; (4) transient ventricular ischaemia, and (5) neurally induced AF. Low level activity (ranging from 0 to 2.7 Hz) generated by 92 neurons was identified in basal states, activities that displayed functional interconnectivity. The majority (56%) of IC neurons so identified received indirect central inputs (vagus alone: 25%; stellate ganglion alone: 27%; both: 48%). Fifty per cent transduced the cardiac milieu responding to multimodal stressors applied to the great vessels or heart. Fifty per cent of IC neurons exhibited cardiac cycle periodicity, with activity occurring primarily in late diastole into isovolumetric contraction. Cardiac-related activity in IC neurons was primarily related to direct cardiac mechano-sensory inputs and indirect autonomic efferent inputs. In response to mediastinal nerve stimulation, most IC neurons became excessively activated; such network behaviour preceded and persisted throughout AF. It was concluded that stochastic interactions occur among IC local circuit neuronal populations in the control of regional cardiac function. Modulation of IC local circuit neuronal recruitment may represent a novel approach for the treatment of cardiac disease, including atrial arrhythmias. PMID:23818689

Self-esteem fluctuations and cardiac vagal control in everyday life.

Science.gov (United States)

Schwerdtfeger, Andreas R; Scheel, Sophie-Marie

2012-03-01

It has been proposed that self-esteem buffers threat-responding. The same effect is ascribed to the vagus nerve, which is a primary nerve of the parasympathetic nervous system. Consequently, it has been suggested that self-esteem and cardiac vagal tone are interconnected on a trait, as well as on a state, level. In this study, we examined the relationship of vagal cardiac control and self-esteem fluctuations across a single day using ecological momentary assessment. Eighty-four participants were recruited, and self-esteem, negative affect, and vagal tone were recorded throughout a 22-hour period. Men provided higher self-esteem ratings than women, but the negative relationship between self-esteem and negative affect was stronger in women. Moreover, controlling for potential confounds (e.g., age, BMI, depressive symptoms, smoking status, regular physical activity), we observed that for men, self-esteem was significantly positively associated with cardiac vagal tone, whereas for women it was not. These findings suggest that the relationship between self-esteem and vagal innervation of the heart during daily life is sex-specific and might involve different central-autonomic pathways for men and women, respectively. Copyright © 2011 Elsevier B.V. All rights reserved.

Effects of CPAP on clinical variables and autonomic modulation in children during an asthma attack.

Science.gov (United States)

de Freitas Dantas Gomes, Evelim Leal; Costa, Dirceu; Germano, Sandra Maria; Borges, Pâmela Vieira; Sampaio, Luciana Maria Malosá

2013-08-01

Continuous positive airway pressure (CPAP) causes changes in alveolar and intrathoracic pressure and the activation of pulmonary stretch receptors affects the balance of the autonomic nervous system. The acute effects of CPAP on autonomic modulation have been demonstrated in different diseases, but no studies have been carried out addressing CPAP in patients with asthma. The hypothesis tested in the present study is that CPAP can produce an autonomic effect beyond a mechanical effect of bronchial dilatation in children with asthma. The results demonstrated improvements in clinical variables and an increase in vagal tone with the administration of CPAP during an asthma attack, as demonstrated by a diminished respiratory rate and a reduction in signs of respiratory distress. Regarding autonomic modulation, an increase in parasympathetic variables was found, indicating non-cholinergic activation stemming from the persistent increase in peak flow. Copyright © 2013 Elsevier B.V. All rights reserved.

Examining the role of TRPA1 in air pollution-induced cardiac arrhythmias and autonomic imbalance

Science.gov (United States)

Here we describe how air pollution causes cardiac arrhythmogenesis through sensory irritation in the airways. Time-series studies show the risk of adverse cardiac events increases significantly in the hours to days after expos...

Heart failure-induced changes of voltage-gated Ca2+ channels and cell excitability in rat cardiac postganglionic neurons.

Science.gov (United States)

Tu, Huiyin; Liu, Jinxu; Zhang, Dongze; Zheng, Hong; Patel, Kaushik P; Cornish, Kurtis G; Wang, Wei-Zhong; Muelleman, Robert L; Li, Yu-Long

2014-01-15

Chronic heart failure (CHF) is characterized by decreased cardiac parasympathetic and increased cardiac sympathetic nerve activity. This autonomic imbalance increases the risk of arrhythmias and sudden death in patients with CHF. We hypothesized that the molecular and cellular alterations of cardiac postganglionic parasympathetic (CPP) neurons located in the intracardiac ganglia and sympathetic (CPS) neurons located in the stellate ganglia (SG) possibly link to the cardiac autonomic imbalance in CHF. Rat CHF was induced by left coronary artery ligation. Single-cell real-time PCR and immunofluorescent data showed that L (Ca(v)1.2 and Ca(v)1.3), P/Q (Ca(v)2.1), N (Ca(v)2.2), and R (Ca(v)2.3) types of Ca2+ channels were expressed in CPP and CPS neurons, but CHF decreased the mRNA and protein expression of only the N-type Ca2+ channels in CPP neurons, and it did not affect mRNA and protein expression of all Ca2+ channel subtypes in the CPS neurons. Patch-clamp recording confirmed that CHF reduced N-type Ca2+ currents and cell excitability in the CPP neurons and enhanced N-type Ca2+ currents and cell excitability in the CPS neurons. N-type Ca2+ channel blocker (1 μM ω-conotoxin GVIA) lowered Ca2+ currents and cell excitability in the CPP and CPS neurons from sham-operated and CHF rats. These results suggest that CHF reduces the N-type Ca2+ channel currents and cell excitability in the CPP neurons and enhances the N-type Ca2+ currents and cell excitability in the CPS neurons, which may contribute to the cardiac autonomic imbalance in CHF.

Autonomic and Renal Alterations in the Offspring of Sleep-Restricted Mothers During Late Pregnancy

Directory of Open Access Journals (Sweden)

Joyce R.S. Raimundo

Full Text Available OBJECTIVES: Considering that changes in the maternal environment may result in changes in progeny, the aim of this study was to investigate the influence of sleep restriction during the last week of pregnancy on renal function and autonomic responses in male descendants at an adult age. METHODS: After confirmation of pregnancy, female Wistar rats were randomly assigned to either a control or a sleep restriction group. The sleep-restricted rats were subjected to sleep restriction using the multiple platforms method for over 20 hours per day between the 14th and 20th day of pregnancy. After delivery, the litters were limited to 6 offspring that were designated as offspring from control and offspring from sleep-restricted mothers. Indirect measurements of systolic blood pressure (BPi, renal plasma flow, glomerular filtration rate, glomerular area and number of glomeruli per field were evaluated at three months of age. Direct measurements of cardiovascular function (heart rate and mean arterial pressure, cardiac sympathetic tone, cardiac parasympathetic tone, and baroreflex sensitivity were evaluated at four months of age. RESULTS: The sleep-restricted offspring presented increases in BPi, glomerular filtration rate and glomerular area compared with the control offspring. The sleep-restricted offspring also showed higher basal heart rate, increased mean arterial pressure, increased sympathetic cardiac tone, decreased parasympathetic cardiac tone and reduced baroreflex sensitivity. CONCLUSIONS: Our data suggest that reductions in sleep during the last week of pregnancy lead to alterations in cardiovascular autonomic regulation and renal morpho-functional changes in offspring, triggering increases in blood pressure.

From Autonomous Systems to Sociotechnical Systems: Designing Effective Collaborations

Directory of Open Access Journals (Sweden)

Kyle J. Behymer

Full Text Available Effectiveness in sociotechnical systems often depends on coordination among multiple agents (including both humans and autonomous technologies. This means that autonomous technologies must be designed to function as collaborative systems, or team players. In many complex work domains, success is beyond the capabilities of humans unaided by technologies. However, at the same time, human capabilities are often critical to ultimate success, as all automated control systems will eventually face problems their designers did not anticipate. Unfortunately, there is often an either/or attitude with respect to humans and technology that tends to focus on optimizing the separate human and autonomous components, with the design of interfaces and team processes as an afterthought. The current paper discusses the limitations of this approach and proposes an alternative where the goal of design is a seamless integration of human and technological capabilities into a well-functioning sociotechnical system. Drawing lessons from both the academic (SRK Framework and commercial (IBM’s Watson, video games worlds, suggestions for enriching the coupling between the human and automated systems by considering both technical and social aspects are discussed.

Imaging of metabolism and autonomic innervation of the heart by positron emission tomography

International Nuclear Information System (INIS)

Melon, P.; Schwaiger, M.

1992-01-01

Positron emission tomography (PET) allows, in combination with multiple radiopharmaceuticals, unique physiological and biochemical tissue characterization. Tracers of blood flow, metabolism and neuronal function have been employed with this technique for research application. More recently, PET has emerged in cardiology as useful for the detection of coronary artery disease and the evaluation of tissue viability. Metabolic tracers such as flourine-18 deoxyglucose (FDG) permit the specific delineation of ischaemically compromised myocardium. Clinical studies have indicated that the metabolic imaging is helpful in selecting patients for coronary artery bypass surgery or coronary angioplasty. More recent research work has concentrated on the use of carbon-11 acetate as a marker of myocardial oxygen consumption. Together with measurements of left ventricular performance, estimates of cardiac efficiency can be derived from dynamic 11 C-acetate studies. The non-invasive evaluation of the autonomic nervous system of the heart was limited in the past. With the introduction of radiopharmaceuticals which specifically bind to neuronal structures, the regional integrity of the autonomic nervous system of the heart can be evaluated with PET. Numerous tracers for pre- and postsynaptic binding sites have been synthesized. 11 C-Hydroxyephedrine represent a new catecholamine analogne which is stored in cardiac presynaptic sympathetic nerve terminals. Initial clinical studies with it suggest a promising role for PET in the study of the sympathetic nervous system in various cardiac diseases such as cardiomyopathy, ischaemic heart disease and diabetes mellitus. The specificity of the radiopharmaceuticals and the quantitative measurements of tissue tracer distribution provided by PET make this technology a very attractive research tool in the cardiovascular sciences with great promise in the area of cardiac metabolism and neurocardiology. (orig.)

Heart rate variability response to mental arithmetic stress in patients with schizophrenia Autonomic response to stress in schizophrenia

NARCIS (Netherlands)

Castro, Mariana N.; Vigo, Daniel E.; Weidema, Hylke; Fahrer, Rodolfo D.; Chu, Elvina M.; De Achaval, Delfina; Nogues, Martin; Leiguarda, Ramon C.; Cardinali, Daniel P.; Guinjoan, Salvador N.

Background: The vulnerability-stress hypothesis is an established model of schizophrenia symptom formation. We sought to characterise the pattern of the cardiac autonomic response to mental arithmetic stress in patients with stable schizophrenia. Methods: We performed heart rate variability (HRV)

Strain-specific patterns of autonomic nervous system activity and heart failure susceptibility in mice.

Science.gov (United States)

Shusterman, Vladimir; Usiene, Irmute; Harrigal, Chivonne; Lee, Joon Sup; Kubota, Toru; Feldman, Arthur M; London, Barry

2002-06-01

Transgenic mice are widely used to study cardiac function, but strain-dependent differences in autonomic nervous system activity (ANSA) have not been explored. We compared 1) short-term pharmacological responses of cardiac rhythm in FVB vs. C57Black6/SV129 wild-type mice and 2) long-term physiological dynamics of cardiac rhythm and survival in tumor necrosis factor (TNF)-alpha transgenic mice with heart failure (TNF-alpha mice) on defined backgrounds. Ambulatory telemetry electrocardiographic recordings and response to saline, adrenergic, and cholinergic agents were examined in FVB and C57Black6/SV129 mice. In FVB mice, baseline heart rate (HR) was higher and did not change after injection of isoproterenol or atropine but decreased with propranolol. In C57Black6/SV129 mice, HR did not change with propranolol but increased with isoproterenol or atropine. Mean HR, but not indexes of HR variability, was an excellent predictor of response to autonomic agents. The proportion of surviving animals was higher in TNF-alpha mice on an FVB background than on a mixed FVB/C57Black6 background. The homeostatic states of ANSA are strain specific, which can explain the interstrain differences in mean HR, pharmacological responses, and survival of animals with congestive heart failure. Strain-specific differences should be considered in selecting the strains of mice used for transgenic and gene targeting experiments.

Postural tachycardia syndrome (POTS) and other autonomic disorders in antiphospholipid (Hughes) syndrome (APS).

Science.gov (United States)

Schofield, J R; Blitshteyn, S; Shoenfeld, Y; Hughes, G R V

2014-06-01

Antiphospholipid syndrome (APS) is an autoimmune hypercoagulable disorder that has been shown to cause a large number of cardiac and neurological manifestations. Two recent studies have demonstrated abnormalities in cardiovascular autonomic function testing in APS patients without other cardiovascular or autoimmune disease. However, an association between autonomic disorders such as postural tachycardia syndrome and APS has not previously been described. Data were obtained by retrospective chart review. We identified 15 patients who have been diagnosed with APS and an autonomic disorder. The median age of the patients at the time of data analysis was 39 years. The autonomic disorders seen in these patients included postural tachycardia syndrome, neurocardiogenic syncope and orthostatic hypotension. The majority of patients (14/15) were female and the majority (14/15) had non-thrombotic neurological manifestations of APS, most commonly migraine, memory loss and balance disorder. Many also had livedo reticularis (11/15) and Raynaud's phenomenon (nine of 15). In some patients, the autonomic manifestations improved with anticoagulation and/or anti-platelet therapy; in others they did not. Two patients with postural tachycardia syndrome who failed to improve with the usual treatment of APS have been treated with intravenous immunoglobulin with significant improvement in their autonomic symptoms. We believe that autonomic disorders in APS may represent an important clinical association with significant implications for treatment. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Chinese-chi and Kundalini yoga Meditations Effects on the Autonomic Nervous System: Comparative Study

Directory of Open Access Journals (Sweden)

Anilesh Dey

2016-06-01

Full Text Available Cardiac disease is one of the major causes for death all over the world. Heart rate variability (HRV is a significant parameter that used in assessing Autonomous Nervous System (ANS activity. Generally, the 2D Poincare′ plot and 3D Poincaré plot of the HRV signals reflect the effect of different external stimuli on the ANS. Meditation is one of such external stimulus, which has different techniques with different types of effects on the ANS. Chinese Chi-meditation and Kundalini yoga are two different effective meditation techniques. The current work is interested with the analysis of the HRV signals under the effect of these two based on meditation techniques. The 2D and 3D Poincare′ plots are generally plotted by fitting respectively an ellipse/ellipsoid to the dense region of the constructed Poincare′ plot of HRV signals. However, the 2D and 3D Poincaré plots sometimes fail to describe the proper behaviour of the system. Thus in this study, a three-dimensional frequency-delay plot is proposed to properly distinguish these two famous meditation techniques by analyzing their effects on ANS. This proposed 3D frequency-delay plot is applied on HRV signals of eight persons practicing same Chi-meditation and four other persons practising same Kundalini yoga. To substantiate the result for larger sample of data, statistical Student t-test is applied, which shows a satisfactory result in this context. The experimental results established that the Chi-meditation has large impact on the HRVcompared to the Kundalini yoga.

Dependency of blood pressure upon cardiac filling in patients with severe postural hypotension

DEFF Research Database (Denmark)

Mehlsen, J; Haedersdal, C; Stokholm, K H

1994-01-01

by vasoconstriction. The reduction in cardiac output resulted from reductions in left ventricular end-diastolic volumes with unchanged left ventricular ejection fractions and only moderate increments in heart rate. The study was demonstrated that blood pressure is strongly dependent upon cardiac filling in severe......Autonomic denervation of the vascular bed results theoretically in a stronger dependency of blood pressure upon intravascular volume, and the study described aimed at an investigation of the relation between cardiac filling and arterial blood pressure in patients with severe postural hypotension....... Seven patients were studied during head-up tilt at three different tilt angles using intra-arterial blood pressure recordings and estimates of left ventricular volumes by radioisotope ventriculography. Blood pressure fell dramatically during head-up tilt due to reductions in cardiac output unopposed...

Dependency of blood pressure upon cardiac filling in patients with severe postural hypotension

DEFF Research Database (Denmark)

Mehlsen, J; Haedersdal, C; Stokholm, K H

1994-01-01

Autonomic denervation of the vascular bed results theoretically in a stronger dependency of blood pressure upon intravascular volume, and the study described aimed at an investigation of the relation between cardiac filling and arterial blood pressure in patients with severe postural hypotension....... Seven patients were studied during head-up tilt at three different tilt angles using intra-arterial blood pressure recordings and estimates of left ventricular volumes by radioisotope ventriculography. Blood pressure fell dramatically during head-up tilt due to reductions in cardiac output unopposed...... by vasoconstriction. The reduction in cardiac output resulted from reductions in left ventricular end-diastolic volumes with unchanged left ventricular ejection fractions and only moderate increments in heart rate. The study was demonstrated that blood pressure is strongly dependent upon cardiac filling in severe...

Are There Deleterious Cardiac Effects of Acute and Chronic Endurance Exercise?

Science.gov (United States)

Eijsvogels, Thijs M. H.; Fernandez, Antonio B.; Thompson, Paul D.

2015-01-01

Multiple epidemiological studies document that habitual physical activity reduces the risk of atherosclerotic cardiovascular disease (ASCVD), and most demonstrate progressively lower rates of ASCVD with progressively more physical activity. Few studies have included individuals performing high-intensity, lifelong endurance exercise, however, and recent reports suggest that prodigious amounts of exercise may increase markers for, and even the incidence of, cardiovascular disease. This review examines the evidence that extremes of endurance exercise may increase cardiovascular disease risk by reviewing the causes and incidence of exercise-related cardiac events, and the acute effects of exercise on cardiovascular function, the effect of exercise on cardiac biomarkers, including “myocardial” creatine kinase, cardiac troponins, and cardiac natriuretic peptides. This review also examines the effect of exercise on coronary atherosclerosis and calcification, the frequency of atrial fibrillation in aging athletes, and the possibility that exercise may be deleterious in individuals genetically predisposed to such cardiac abnormalities as long QT syndrome, right ventricular cardiomyopathy, and hypertrophic cardiomyopathy. This review is to our knowledge unique because it addresses all known potentially adverse cardiovascular effects of endurance exercise. The best evidence remains that physical activity and exercise training benefit the population, but it is possible that prolonged exercise and exercise training can adversely affect cardiac function in some individuals. This hypothesis warrants further examination. PMID:26607287

Effect of experimental hyperthyroidism on protein turnover in skeletal and cardiac muscle.

Science.gov (United States)

Carter, W J; Van Der Weijden Benjamin, W S; Faas, F H

1980-10-01

Since experimental hyperthyroidism reduces skeletal muscle mass while simultaneously increasing cardiac muscle mass, the effect of hyperthyroidism on muscle protein degradation was compared in skeletal and cardiac muscle. Pulse-labeling studies using (3H) leucine and (14C) carboxyl labeled aspartate and glutamate were carried out. Hyperthyroidism caused a 25%-29% increase in protein breakdown in both sarcoplasmic and myofibrillar fractions of skeletal muscle. Increased muscle protein degradation may be a major factor in the development of skeletal muscle wasting and weakness in hyperthyroidism. In contrast, protein breakdown appeared to be reduced 22% in the sarcoplasmic fraction of hyperthyroid heart muscle and was unchanged in the myofibrillar fraction. Possible reasons for the contrasting effects of hyperthyroidism on skeletal and cardiac muscle include increased sensitivity of the hyperthyroid heart to catecholamines, increased cardiac work caused by the hemodynamic effects of hyperthyroidism, and a different direct effect of thyroid hormone at the nuclear level in cardiac as opposed to skeletal muscle.

Cardiovascular autonomic dysfunction in primary ovarian insufficiency: clinical and experimental evidence

Science.gov (United States)

Goldmeier, Silvia; De Angelis, Kátia; Rabello Casali, Karina; Vilodre, César; Consolim-Colombo, Fernanda; Belló Klein, Adriane; Plentz, Rodrigo; Spritzer, PoliMara; Irigoyen, Maria-Cláudia

2014-01-01

Objective: Women with primary ovarian insufficiency (POI) present an increased risk for cardiovascular disease. In this study we tested the hypothesis that POI in women under hormone therapy (HT) are associated with vascular vasodilatation attenuation and cardiovascular autonomic dysfunction and these impairments are related to changes in systemic antioxidant enzymes. Furthermore, the possibility that ovarian hormone deprivation can induce such changes and that HT cannot reverse all of those impairments was examined in an experimental model of POI. Methods: Fifteen control and 17 patients with primary ovarian insufficiency receiving HT were included in the study. To test the systemic and cardiac consequences of ovarian hormone deprivation, ovariectomy was induced in young female rats that were submitted or not to HT. Spectral analysis of RR interval and blood pressure signals were performed and oxidative stress parameters were determined. Results: POI women under HT have increased mean arterial pressure (94±10 vs. 86±5 mmHg) despite normal endothelial and autonomic modulation of vasculature. Additionally, they presented impaired baroreflex sensitivity (3.9±1.38 vs. 7.15±3.62 ms/mmHg) and reduced heart rate variability (2310±1173 vs. 3754±1921 ms2). Similar results obtained in ovariectomized female rats were accompanied by an increased lipoperoxidation (7433±1010 vs. 6180±289 cps/mg protein) and decreased antioxidant enzymes in cardiac tissue. As it was observed in women, the HT in animals did not restore hemodynamic and autonomic dysfunctions. Conclusion: These data provide clinical and experimental evidence that long term HT may not restore all cardiovascular risk factors associated with ovarian hormone deprivation. PMID:24349626

Relationships between thermic effect of food, insulin resistance and autonomic nervous activity

OpenAIRE

Watanabe, Tomonori; Nomura, Masahiro; Nakayasu, Kimiko; Kawano, Tomohito; Ito, Susumu; Nakaya, Yutaka

2006-01-01

Background: The thermic effect of food (TEF) is higher in lean than in obese human subjects. Objective: Relationships between TEF and insulin resistance during meals, from the point of view of autonomic nervous activity, were evaluated. Methods : Autonomic nervous activity was evaluated in 20 young adults using the spectral analysis of heart rate variability from one hour before to two hours after a meal. Heart rate data were analyzed based on low frequency components (LF power, 0.04 - 0.15Hz...

AUTONOMIC CARDIOVASCULAR REGULATION DISORDERS IN PATIENTS WITH PSORIATIC ARTHRITIS

Directory of Open Access Journals (Sweden)

A. P. Rebrov

2011-01-01

Full Text Available Aim – to identify disorders of autonomic regulation of cardiac activity in patients with psoriatic arthritis (PsA by determining the heart rate variability (HRV, and also establish the relationship of HRV with systemic inflammation and traditional cardiovascular risk factors.Materials and methods. The study included 53 patients with PsA (mean age 43.64 ± 12.1 years, including 48.2 % men, mean disease durationwas 10.32 ± 10.2 years. The control group included 25 healthy volunteers (average age 46.7 ± 12.45 years, 49.1 % – men. Time andfrequency measures of HRV were analyzed. Active PsA was determined by an index DAS4, rate erythrocyte sedimentation rate (ESR, levels of C-reactive protein (CRP and fibrinogen. Patients with clinical manifestations of cardiovascular disease, and patients with symptomsof carotid atherosclerosis, detected by duplex study were excluded.Results. Deterioration of HRV in patients with PsA compared with those in patients of the control group, the availability of statistically significant reverse relationship of temporal and spectral parameters of HRV with PsA activity (ESR, CRP, entezit score, DAS4, duration of arthritis, the classical factors of cardiovascular risk were established.Conclusion. Patients with PsA had noted a violation of autonomic regulation of cardiac activity in the form of reduced HRV and activation of the sympathetic part of it. Identified changes were associated with activity of systemic inflammation and classical factors of cardiovascular risk.

AUTONOMIC CARDIOVASCULAR REGULATION DISORDERS IN PATIENTS WITH PSORIATIC ARTHRITIS

Directory of Open Access Journals (Sweden)

A. P. Rebrov

2014-07-01

Full Text Available Aim – to identify disorders of autonomic regulation of cardiac activity in patients with psoriatic arthritis (PsA by determining the heart rate variability (HRV, and also establish the relationship of HRV with systemic inflammation and traditional cardiovascular risk factors.Materials and methods. The study included 53 patients with PsA (mean age 43.64 ± 12.1 years, including 48.2 % men, mean disease durationwas 10.32 ± 10.2 years. The control group included 25 healthy volunteers (average age 46.7 ± 12.45 years, 49.1 % – men. Time andfrequency measures of HRV were analyzed. Active PsA was determined by an index DAS4, rate erythrocyte sedimentation rate (ESR, levels of C-reactive protein (CRP and fibrinogen. Patients with clinical manifestations of cardiovascular disease, and patients with symptomsof carotid atherosclerosis, detected by duplex study were excluded.Results. Deterioration of HRV in patients with PsA compared with those in patients of the control group, the availability of statistically significant reverse relationship of temporal and spectral parameters of HRV with PsA activity (ESR, CRP, entezit score, DAS4, duration of arthritis, the classical factors of cardiovascular risk were established.Conclusion. Patients with PsA had noted a violation of autonomic regulation of cardiac activity in the form of reduced HRV and activation of the sympathetic part of it. Identified changes were associated with activity of systemic inflammation and classical factors of cardiovascular risk.

The effects of autonomous learning on cognitive load and learning results

NARCIS (Netherlands)

Gorissen, Chantal; Kester, Liesbeth; Brand-Gruwel, Saskia; Martens, Rob

2012-01-01

Gorissen, C. J. J., Kester, L., Brand-Gruwel, S., & Martens, R. L. (2011, August). The Effects of Autonomous Learning on Cognitive Load and Learning Results. Presentation at the EARLI conference. Exeter, UK.

Autonomic and Vascular Control in Prehypertensive Subjects with a Family History of Arterial Hypertension

Directory of Open Access Journals (Sweden)

Josária Ferraz Amaral

2018-02-01

Full Text Available Abstract Background: Individuals with a family history of systemic arterial hypertension (FHSAH and / or prehypertension have a higher risk of developing this pathology. Objective: To evaluate the autonomic and vascular functions of prehypertensive patients with FHSAH. Methods: Twenty-five young volunteers with FHSAH, 14 normotensive and 11 prehypertensive subjects were submitted to vascular function evaluation by forearm vascular conductance(VC during resting and reactive hyperemia (Hokanson® and cardiac and peripheral autonomic modulation, quantified, respectively, by spectral analysis of heart rate (ECG and systolic blood pressure (SBP (FinometerPRO®. The transfer function analysis was used to measure the gain and response time of baroreflex. The statistical significance adopted was p ≤ 0.05. Results: Pre-hypertensive individuals, in relation to normotensive individuals, have higher VC both at rest (3.48 ± 1.26 vs. 2.67 ± 0.72 units, p = 0.05 and peak reactive hyperemia (25, 02 ± 8.18 vs. 18.66 ± 6.07 units, p = 0.04. The indices of cardiac autonomic modulation were similar between the groups. However, in the peripheral autonomic modulation, greater variability was observed in prehypertensive patients compared to normotensive individuals (9.4 [4.9-12.7] vs. 18.3 [14.8-26.7] mmHg2; p < 0.01 and higher spectral components of very low (6.9 [2.0-11.1] vs. 13.5 [10.7-22.4] mmHg2, p = 0.01 and low frequencies (1.7 [1.0-3.0] vs. 3.0 [2.0-4.0] mmHg2, p = 0.04 of SBP. Additionally, we observed a lower gain of baroreflex control in prehypertensive patients compared to normotensive patients (12.16 ± 4.18 vs. 18.23 ± 7.11 ms/mmHg, p = 0.03, but similar delay time (-1.55 ± 0.66 vs. -1.58 ± 0.72 s, p = 0.90. Conclusion: Prehypertensive patients with FHSAH have autonomic dysfunction and increased vascular conductance when compared to normotensive patients with the same risk factor.

Role of Training and Detraining on Inflammatory and Metabolic Profile in Infarcted Rats: Influences of Cardiovascular Autonomic Nervous System

Science.gov (United States)

Santana, Aline Alves; Santamarina, Aline Boveto; Oyama, Lila Missae; Caperuto, Érico Chagas; de Souza, Cláudio Teodoro; Barboza, Catarina de Andrade; Rocha, Leandro Yanase; Figueroa, Diego; Mostarda, Cristiano; Irigoyen, Maria Cláudia; Lira, Fábio Santos

2014-01-01

The aim of this study was to evaluate the effects of exercise training (ET, 50–70% of VO2 max, 5 days/week) and detraining (DT) on inflammatory and metabolic profile after myocardial infarction (MI) in rats. Male Wistar rats were divided into control (C, n = 8), sedentary infarcted (SI, n = 9), trained infarcted (TI, n = 10; 3 months of ET), and detrained infarcted (DI, n = 11; 2 months of ET + 1 month of DT). After ET and DT protocols, ventricular function and inflammation, cardiovascular autonomic modulation (spectral analysis), and adipose tissue inflammation and lipolytic pathway were evaluated. ET after MI improved cardiac and vascular autonomic modulation, and these benefits were correlated with reduced inflammatory cytokines on the heart and adipose tissue. These positive changes were sustained even after 1 month of detraining. No expressive changes were observed in oxidative stress and lipolytic pathway in experimental groups. In conclusion, our results strongly suggest that the autonomic improvement promoted by ET, and maintained even after the detraining period, was associated with reduced inflammatory profile in the left ventricle and adipose tissue of rats subjected to MI. These data encourage enhancing cardiovascular autonomic function as a therapeutic strategy for the treatment of inflammatory process triggered by MI. PMID:25045207

Role of Training and Detraining on Inflammatory and Metabolic Profile in Infarcted Rats: Influences of Cardiovascular Autonomic Nervous System

Directory of Open Access Journals (Sweden)

Bruno Rodrigues

2014-01-01

Full Text Available The aim of this study was to evaluate the effects of exercise training (ET, 50–70% of VO2 max, 5 days/week and detraining (DT on inflammatory and metabolic profile after myocardial infarction (MI in rats. Male Wistar rats were divided into control (C, n=8, sedentary infarcted (SI, n=9, trained infarcted (TI,  n=10; 3 months of ET, and detrained infarcted (DI, n=11; 2 months of ET + 1 month of DT. After ET and DT protocols, ventricular function and inflammation, cardiovascular autonomic modulation (spectral analysis, and adipose tissue inflammation and lipolytic pathway were evaluated. ET after MI improved cardiac and vascular autonomic modulation, and these benefits were correlated with reduced inflammatory cytokines on the heart and adipose tissue. These positive changes were sustained even after 1 month of detraining. No expressive changes were observed in oxidative stress and lipolytic pathway in experimental groups. In conclusion, our results strongly suggest that the autonomic improvement promoted by ET, and maintained even after the detraining period, was associated with reduced inflammatory profile in the left ventricle and adipose tissue of rats subjected to MI. These data encourage enhancing cardiovascular autonomic function as a therapeutic strategy for the treatment of inflammatory process triggered by MI.

Evaluation of cardiac autonomic nerves by iodine-123 metaiodobenzylguanidine scintigraphy and ambulatory electrocardiography in patients after arterial switch operations

Energy Technology Data Exchange (ETDEWEB)

Sakurai, Hajime; Maeda, Masanobu; Miyahara, Ken [Shakaihoken Chukyo Hospital, Nagoya (Japan)] [and others

2000-05-01

The autonomic cardiac nerves reach the heart after passing through the vicinity of the aortic root and the pulmonary trunk. The arterial switch operation (ASO) completely transects the ascending aorta and the pulmonary trunk. Therefore, this surgical procedure virtually denerves the heart. Cardiac sympathetic denervation and reinnervation were evaluated in patients after ASO using iodine-123 metaiodobenzylguanidine (MIBG) myocardial scintigraphy and parasympathetic denervation and reinnervation using ambulatory electrocardiography [Holter electrocardiogram (ECG)]. MIBG scintigraphy was performed in 14 patients who underwent ASO (ASO group) and 3 patients who underwent other open heart surgery (control group). All patients in the ASO group underwent the operation in the neonatal or infantile period. Planar and single photon emission computed tomography (SPECT) images of the myocardium were obtained. Defect score was determined by the SPECT images as a semi-quantitative index. The mean interval between ASO and MIBG scintigraphy was 25.6{+-}14.6 months. Holter ECG was also performed in 14 patients in the ASO group and 19 age-matched normal children. The Holter ECGs were plotted on a Lorenz plot. The H index, which is related to vagal tone for the cardiovascular system, was calculated from the R-R intervals. The mean interval between the ASO and Holter ECG was 8.3{+-}9.7 months. MIBG scintigraphy in the control group demonstrated an almost normal homogeneous tracer uptake, but showed extremely reduced tracer uptake and significantly higher defect score in the ASO group. The extent and degree of the reduction of MIBG uptake improved with time after the ASO. The heart-to-mediastinum MIBG count ratio tended to increase with time. The H index of the ASO group was lower than that of normal children (<12 months: Control group 0.0280{+-}0.0068 vs ASO group 0.0219{+-}0.0083), and gradually increased with time (1-3 years: 0.0470{+-}0.0157 vs 0.0314{+-}0.0124). (author)

Evaluation of cardiac autonomic nerves by iodine-123 metaiodobenzylguanidine scintigraphy and ambulatory electrocardiography in patients after arterial switch operations

International Nuclear Information System (INIS)

Sakurai, Hajime; Maeda, Masanobu; Miyahara, Ken

2000-01-01

The autonomic cardiac nerves reach the heart after passing through the vicinity of the aortic root and the pulmonary trunk. The arterial switch operation (ASO) completely transects the ascending aorta and the pulmonary trunk. Therefore, this surgical procedure virtually denerves the heart. Cardiac sympathetic denervation and reinnervation were evaluated in patients after ASO using iodine-123 metaiodobenzylguanidine (MIBG) myocardial scintigraphy and parasympathetic denervation and reinnervation using ambulatory electrocardiography [Holter electrocardiogram (ECG)]. MIBG scintigraphy was performed in 14 patients who underwent ASO (ASO group) and 3 patients who underwent other open heart surgery (control group). All patients in the ASO group underwent the operation in the neonatal or infantile period. Planar and single photon emission computed tomography (SPECT) images of the myocardium were obtained. Defect score was determined by the SPECT images as a semi-quantitative index. The mean interval between ASO and MIBG scintigraphy was 25.6±14.6 months. Holter ECG was also performed in 14 patients in the ASO group and 19 age-matched normal children. The Holter ECGs were plotted on a Lorenz plot. The H index, which is related to vagal tone for the cardiovascular system, was calculated from the R-R intervals. The mean interval between the ASO and Holter ECG was 8.3±9.7 months. MIBG scintigraphy in the control group demonstrated an almost normal homogeneous tracer uptake, but showed extremely reduced tracer uptake and significantly higher defect score in the ASO group. The extent and degree of the reduction of MIBG uptake improved with time after the ASO. The heart-to-mediastinum MIBG count ratio tended to increase with time. The H index of the ASO group was lower than that of normal children (<12 months: Control group 0.0280±0.0068 vs ASO group 0.0219±0.0083), and gradually increased with time (1-3 years: 0.0470±0.0157 vs 0.0314±0.0124). (author)

Clonidine, an alpha2-receptor agonist, diminishes GABAergic neurotransmission to cardiac vagal neurons in the nucleus ambiguus.

Science.gov (United States)

Philbin, Kerry E; Bateman, Ryan J; Mendelowitz, David

2010-08-06

In hypertension, there is an autonomic imbalance in which sympathetic activity dominates over parasympathetic control. Parasympathetic activity to the heart originates from cardiac vagal neurons located in the nucleus ambiguus. Presympathetic neurons that project to sympathetic neurons in the spinal cord are located in the ventral brainstem in close proximity to cardiac vagal neurons, and many of these presympathetic neurons are catecholaminergic. In addition to their projection to the spinal cord, many of these presympathetic neurons have axon collaterals that arborize into neighboring cardiorespiratory locations and likely release norepinephrine onto nearby neurons. Activation of alpha(2)-adrenergic receptors in the central nervous system evokes a diverse range of physiological effects, including reducing blood pressure. This study tests whether clonidine, an alpha(2)-adrenergic receptor agonist, alters excitatory glutamatergic, and/or inhibitory GABAergic or glycinergic synaptic neurotransmission to cardiac vagal neurons in the nucleus ambiguus. Cardiac vagal neurons were identified in an in vitro brainstem slice preparation, and synaptic events were recording using whole cell voltage clamp methodologies. Clonidine significantly inhibited GABAergic neurotransmission but had no effect on glycinergic or glutamatergic pathways to cardiac vagal neurons. This diminished inhibitory GABAergic neurotransmission to cardiac vagal neurons would increase parasympathetic activity to the heart, decreasing heart rate and blood pressure. The results presented here provide a cellular substrate for the clinical use of clonidine as a treatment for hypertension as well as a role in alleviating posttraumatic stress disorder by evoking an increase in parasympathetic cardiac vagal activity, and a decrease in heart rate and blood pressure. Copyright 2010 Elsevier B.V. All rights reserved.

Iyengar Yoga Increases Cardiac Parasympathetic Nervous Modulation among Healthy Yoga Practitioners

Directory of Open Access Journals (Sweden)

Kerstin Khattab

2007-01-01

Full Text Available Relaxation techniques are established in managing of cardiac patients during rehabilitation aiming to reduce future adverse cardiac events. It has been hypothesized that relaxation-training programs may significantly improve cardiac autonomic nervous tone. However, this has not been proven for all available relaxation techniques. We tested this assumption by investigating cardiac vagal modulation during yoga.We examined 11 healthy yoga practitioners (7 women and 4 men, mean age: 43 ± 11; range: 26–58 years. Each individual was subjected to training units of 90 min once a week over five successive weeks. During two sessions, they practiced a yoga program developed for cardiac patients by B.K.S. Iyengar. On three sessions, they practiced a placebo program of relaxation. On each training day they underwent ambulatory 24 h Holter monitoring. The group of yoga practitioners was compared to a matched group of healthy individuals not practicing any relaxation techniques. Parameters of heart rate variability (HRV were determined hourly by a blinded observer. Mean RR interval (interval between two R-waves of the ECG was significantly higher during the time of yoga intervention compared to placebo and to control (P < 0.001 for both. The increase in HRV parameters was significantly higher during yoga exercise than during placebo and control especially for the parameters associated with vagal tone, i.e. mean standard deviation of NN (Normal Beat to Normal Beat of the ECG intervals for all 5-min intervals (SDNNi, P < 0.001 for both and root mean square successive difference (rMSSD, P < 0.01 for both. In conclusion, relaxation by yoga training is associated with a significant increase of cardiac vagal modulation. Since this method is easy to apply with no side effects, it could be a suitable intervention in cardiac rehabilitation programs.

A non-cardiomyocyte autonomous mechanism of cardioprotection involving the SLO1 BK channel

Directory of Open Access Journals (Sweden)

Andrew P. Wojtovich

2013-03-01

Full Text Available Opening of BK-type Ca2+ activated K+ channels protects the heart against ischemia-reperfusion (IR injury. However, the location of BK channels responsible for cardioprotection is debated. Herein we confirmed that openers of the SLO1 BK channel, NS1619 and NS11021, were protective in a mouse perfused heart model of IR injury. As anticipated, deletion of the Slo1 gene blocked this protection. However, in an isolated cardiomyocyte model of IR injury, protection by NS1619 and NS11021 was insensitive to Slo1 deletion. These data suggest that protection in intact hearts occurs by a non-cardiomyocyte autonomous, SLO1-dependent, mechanism. In this regard, an in-situ assay of intrinsic cardiac neuronal function (tachycardic response to nicotine revealed that NS1619 preserved cardiac neurons following IR injury. Furthermore, blockade of synaptic transmission by hexamethonium suppressed cardioprotection by NS1619 in intact hearts. These results suggest that opening SLO1 protects the heart during IR injury, via a mechanism that involves intrinsic cardiac neurons. Cardiac neuronal ion channels may be useful therapeutic targets for eliciting cardioprotection.

On the Evolution of the Cardiac Pacemaker

Directory of Open Access Journals (Sweden)

Silja Burkhard

2017-04-01

Full Text Available The rhythmic contraction of the heart is initiated and controlled by an intrinsic pacemaker system. Cardiac contractions commence at very early embryonic stages and coordination remains crucial for survival. The underlying molecular mechanisms of pacemaker cell development and function are still not fully understood. Heart form and function show high evolutionary conservation. Even in simple contractile cardiac tubes in primitive invertebrates, cardiac function is controlled by intrinsic, autonomous pacemaker cells. Understanding the evolutionary origin and development of cardiac pacemaker cells will help us outline the important pathways and factors involved. Key patterning factors, such as the homeodomain transcription factors Nkx2.5 and Shox2, and the LIM-homeodomain transcription factor Islet-1, components of the T-box (Tbx, and bone morphogenic protein (Bmp families are well conserved. Here we compare the dominant pacemaking systems in various organisms with respect to the underlying molecular regulation. Comparative analysis of the pathways involved in patterning the pacemaker domain in an evolutionary context might help us outline a common fundamental pacemaker cell gene programme. Special focus is given to pacemaker development in zebrafish, an extensively used model for vertebrate development. Finally, we conclude with a summary of highly conserved key factors in pacemaker cell development and function.

On the Evolution of the Cardiac Pacemaker

Science.gov (United States)

Burkhard, Silja; van Eif, Vincent; Garric, Laurence; Christoffels, Vincent M.; Bakkers, Jeroen

2017-01-01

The rhythmic contraction of the heart is initiated and controlled by an intrinsic pacemaker system. Cardiac contractions commence at very early embryonic stages and coordination remains crucial for survival. The underlying molecular mechanisms of pacemaker cell development and function are still not fully understood. Heart form and function show high evolutionary conservation. Even in simple contractile cardiac tubes in primitive invertebrates, cardiac function is controlled by intrinsic, autonomous pacemaker cells. Understanding the evolutionary origin and development of cardiac pacemaker cells will help us outline the important pathways and factors involved. Key patterning factors, such as the homeodomain transcription factors Nkx2.5 and Shox2, and the LIM-homeodomain transcription factor Islet-1, components of the T-box (Tbx), and bone morphogenic protein (Bmp) families are well conserved. Here we compare the dominant pacemaking systems in various organisms with respect to the underlying molecular regulation. Comparative analysis of the pathways involved in patterning the pacemaker domain in an evolutionary context might help us outline a common fundamental pacemaker cell gene programme. Special focus is given to pacemaker development in zebrafish, an extensively used model for vertebrate development. Finally, we conclude with a summary of highly conserved key factors in pacemaker cell development and function. PMID:29367536

Effects of n-3 polyunsaturated fatty acids on cardiac ion channels

Directory of Open Access Journals (Sweden)

Cristina eMoreno

2012-07-01

Full Text Available Dietary n-3 polyunsaturated fatty acids (PUFAs have been reported to exhibit antiarrhythmic properties, attributed to their capability to modulate ion channels. In the present review, we will focus on the effects of PUFAs on cardiac sodium channel (Nav1.5 and two potassium channels (Kv (Kv1.5 and Kv11.1. n-3 marine (docohexaenoic and eicohexapentaenoic acid and plant origin (alpha-linolenic acid PUFAs block Kv1.5 and Kv11.1 channels at physiological concentrations. Also, DHA and EPA decreased Nav1.5 and calcium channels. These effects on Na and Ca channels theoretically should shorten the cardiac APD, whereas the blocking actions of n-3 PUFAs of Kv channels should lengthen the cardiac action potential. Experiments performed in female rabbits fed with a diet rich in n-3 PUFAs show a longer cardiac action potential and effective refractory period. This study was performed to analyze if their antiarrhythmic effects are due to a reduction of triangulation, reverse use-dependence, instability and dispersion of the cardiac action potential (TRIaD as a measure of proarrhythmic effects. Dietary n-3 PUFAs supplementation markedly reduced dofetilide-induced TRIaD and abolished dofetilide-induced torsades de pointes (TdP. Ultrafast sodium channel block by DHA may account for the antiarrhythmic protection of dietary supplements of n-3 PUFAs against dofetilide induced proarrhythmia observed in this animal model. The cardiac effects of n-3 PUFAs resemble those of amiodarone: both block sodium, calcium and potassium channels, have anti-adrenergic properties, can prolong the cardiac action potential, reverse TRIaD and suppress TdP. The main difference is that sodium channel block by n-3 PUFAs has a much faster onset and offset kinetics. Therefore, the electrophysiological profile of n-3 PUFAs appears more desirable: the duration of reduced sodium current (facilitates re-entry is much shorter. The n-3 PUFAs appear as a safer alternative to other antiarrhythmic

Nocturnal antihypertensive treatment in patients with type 1 diabetes with autonomic neuropathy and non-dipping of blood pressure during night time

DEFF Research Database (Denmark)

Hjortkær, Henrik; Jensen, Tonny; Kofoed, Klaus

2014-01-01

INTRODUCTION: Cardiac autonomic neuropathy (CAN) and elevated nocturnal blood pressure are independent risk factors for cardiovascular disease in patients with diabetes. Previously, associations between CAN, non-dipping of nocturnal blood pressure and coronary artery calcification have been...

Monosodium glutamate neonatal treatment induces cardiovascular autonomic function changes in rodents

Directory of Open Access Journals (Sweden)

Signorá Peres Konrad

2012-10-01

Full Text Available OBJECTIVES: The aim of this study was to evaluate cardiovascular autonomic function in a rodent obesity model induced by monosodium glutamate injections during the first seven days of life. METHOD: The animals were assigned to control (control, n = 10 and monosodium glutamate (monosodium glutamate, n = 13 groups. Thirty-three weeks after birth, arterial and venous catheters were implanted for arterial pressure measurements, drug administration, and blood sampling. Baroreflex sensitivity was evaluated according to the tachycardic and bradycardic responses induced by sodium nitroprusside and phenylephrine infusion, respectively. Sympathetic and vagal effects were determined by administering methylatropine and propranolol. RESULTS: Body weight, Lee index, and epididymal white adipose tissue values were higher in the monosodium glutamate group in comparison to the control group. The monosodium glutamate-treated rats displayed insulin resistance, as shown by a reduced glucose/insulin index (-62.5%, an increased area under the curve of total insulin secretion during glucose overload (39.3%, and basal hyperinsulinemia. The mean arterial pressure values were higher in the monosodium glutamate rats, whereas heart rate variability (>7 times, bradycardic responses (>4 times, and vagal (~38% and sympathetic effects (~36% were reduced as compared to the control group. CONCLUSION: Our results suggest that obesity induced by neonatal monosodium glutamate treatment impairs cardiac autonomic function and most likely contributes to increased arterial pressure and insulin resistance.

Cardiovascular Autonomic Responses in the VCD Rat Model of Menopause: Effects of Short- and Long-Term Ovarian Failure.

Science.gov (United States)

Huber, Domitila A; Bazilio, Darlan; Lorenzon, Flaviano; Sehnem, Sibele; Pacheco, Lucas; Anselmo-Franci, Janete A; Lima, Fernanda B

2017-01-01

After menopause, hypertension elevates the risk of cardiac diseases, one of the major causes of women's morbidity. The gradual depletion of ovarian follicles in rats, induced by 4-vinylcyclohexene diepoxide (VCD), is a model for studying the physiology of menopause. 4-Vinylcyclohexene diepoxide treatment leads to early ovarian failure (OF) and a hormonal profile comparable to menopause in humans. We have hypothesized that OF can compromise the balance between sympathetic and parasympathetic tones of the cardiovascular system, shifting toward dominance of the former. We aimed to study the autonomic modulation of heart and blood vessels and the cardiovascular reflexes in rats presenting short-term (80 days) or long-term (180 days) OF induced by VCD. Twenty-eight-day-old Wistar rats were submitted to VCD treatment (160 mg/kg, intraperitoneally) or vehicle (control) for 15 consecutive days and experiments were conducted at 80 or 180 days after the onset of treatment. Long-term OF led to an increase in the sympathetic activity to blood vessels and an impairment in the baroreflex control of the heart, evoked by physiological changes in arterial pressure. Despite that, long-term OF did not cause hypertension during the 180 days of exposure. Short-term OF did not cause any deleterious effect on the cardiovascular parameters analyzed. These data indicate that long-term OF does not disrupt the maintenance of arterial pressure homeostasis in rats but worsens the autonomic cardiovascular control. In turn, this can lead to cardiovascular complications, especially when associated with the aging process seen during human menopause.

Autonomic nervous system profile in fibromyalgia patients and its modulation by exercise: a mini review.

Science.gov (United States)

Kulshreshtha, Poorvi; Deepak, Kishore K

2013-03-01

This review imparts an impressionistic tone to our current understanding of autonomic nervous system abnormalities in fibromyalgia. In the wake of symptoms present in patients with fibromyalgia (FM), autonomic dysfunction seems plausible in fibromyalgia. A popular notion is that of a relentless sympathetic hyperactivity and hyporeactivity based on heart rate variability (HRV) analyses and responses to various physiological stimuli. However, some exactly opposite findings suggesting normal/hypersympathetic reactivity in patients with fibromyalgia do exist. This heterogeneous picture along with multiple comorbidities accounts for the quantitative and qualitative differences in the degree of dysautonomia present in patients with FM. We contend that HRV changes in fibromyalgia may not actually represent increased cardiac sympathetic tone. Normal muscle sympathetic nerve activity (MSNA) and normal autonomic reactivity tests in patients with fibromyalgia suggest defective vascular end organ in fibromyalgia. Previously, we proposed a model linking deconditioning with physical inactivity resulting from widespread pain in patients with fibromyalgia. Deconditioning also modulates the autonomic nervous system (high sympathetic tone and a low parasympathetic tone). A high peripheral sympathetic tone causes regional ischaemia, which in turn results in widespread pain. Thus, vascular dysregulation and hypoperfusion in patients with FM give rise to ischaemic pain leading to physical inactivity. Microvascular abnormalities are also found in patients with FM. Therapeutic interventions (e.g. exercise) that result in vasodilatation and favourable autonomic alterations have proven to be effective. In this review, we focus on the vascular end organ in patients with fibromyalgia in particular and its modulation by exercise in general. © 2012 The Authors Clinical Physiology and Functional Imaging © 2012 Scandinavian Society of Clinical Physiology and Nuclear Medicine.

Analgesic and anti-inflammatory effects of honey: the involvement of autonomic receptors.

Science.gov (United States)

Owoyele, Bamidele Victor; Oladejo, Rasheed Olajiire; Ajomale, Kayode; Ahmed, Rasheedat Omotayo; Mustapha, Abdulrasheed

2014-03-01

The use of honey for therapeutic purposes is on the increase and many studies have shown that honey has the ability to influence biological systems including pain transmission. Therefore, this study was designed to investigate the analgesic and anti-inflammatory effects of honey and the effects of concurrent administration of autonomic nervous system blocking drugs. Studies on analgesic activities was carried out using hotplate and formalin-induced paw licking models while the anti-inflammatory activity was by the carrageenan paw oedema method. Animals were distributed into six groups consisting of five animals each. They were administered saline, honey (600 mg/kg), indomethacin (5 mg/kg), autonomic blockers (3 μg/kg of tamsulosin, 20 mg/kg (intraperitoneally) of propranolol, 2 ml/kg of atropine or 10 mg/kg (intra muscularly) of hexamethonium) or honey (200 and 600 mg/kg) with one of the blockers. The results showed that honey reduced pain perception especially inflammatory pain and the administration of tamsulosin and propranolol spared the effect of honey. Hexamethonium also spared the effects of honey at the early and late phases of the test while atropine only inhibited the early phase of the test. However, atropine and hexamethonium spared the anti-inflammatory effects of honey but tamsulosin abolished the effects while propranolol only abolished the anti-inflammatory effects at the peak of the inflammation. The results suggest the involvement of autonomic receptors in the anti-nociceptive and anti-inflammatory effects of honey although the level of involvement depends on the different types of the receptors.

Empagliflozin lessened cardiac injury and reduced visceral adipocyte hypertrophy in prediabetic rats with metabolic syndrome.

Science.gov (United States)

Kusaka, Hiroaki; Koibuchi, Nobutaka; Hasegawa, Yu; Ogawa, Hisao; Kim-Mitsuyama, Shokei

2016-11-11

The potential benefit of SGLT2 inhibitors in metabolic syndrome is with prediabetic stage unclear. This work was undertaken to investigate the non-glycemic effect of empagliflozin on metabolic syndrome rats with prediabetes. SHR/NDmcr-cp(+/+) rats (SHRcp), a model of metabolic syndrome with prediabetes, were given empagliflozin for 10 weeks to examine the effects on urinary sodium and water balance, visceral and subcutaneous adipocyte, and cardiac injury. Further, the effect of empagliflozin on blood pressure and autonomic nervous system was continuously investigated by using radiotelemetry system. Empagliflozin significantly reduced urinary sodium and water balance of SHRcp only within 1 week of the treatment, but later than 1 week did not alter them throughout the treatment. Empagliflozin significantly reduced body weight of SHRcp, which was mainly attributed to the significant reduction of subcutaneous fat mass. Empagliflozin significantly reduced the size of visceral adipocytes and increased the number of smaller size of adipocytes, which was associated with the attenuation of oxidative stress. Empagliflozin ameliorated cardiac hypertrophy and fibrosis of SHRcp, in association with the attenuation of cardiac oxidative stress and inflammation. However, empagliflozin did not significantly change blood pressure, heart rate, sympathetic activity, or baroreceptor function, as evidenced by radiotelemetry analysis. Our present work provided the evidence that SGLT2 inhibition reduced visceral adipocytes hypertrophy and ameliorated cardiac injury in prediabetic metabolic syndrome rat, independently of diuretic effect or blood pressure lowering effect. Thus, SGLT2 inhibition seems to be a promising therapeutic strategy for prediabetic metabolic syndrome.

Clonidine, an α2 receptor agonist, diminishes GABAergic neurotransmission to cardiac vagal neurons in the nucleus ambiguus

OpenAIRE

Philbin, Kerry E.; Bateman, Ryan J.; Mendelowitz, David

2010-01-01

In hypertension there is an autonomic imbalance in which sympathetic activity dominates over parasympathetic control. Parasympathetic activity to the heart originates from cardiac vagal neurons located in the nucleus ambiguus. Pre-sympathetic neurons that project to sympathetic neurons in the spinal cord are located in the ventral brainstem in close proximity to cardiac vagal neurons, and many of these pre-sympathetic neurons are catecholaminergic. In addition to their projection to the spina...

Insights into the background of autonomic medicine.

Science.gov (United States)

Laranjo, Sérgio; Geraldes, Vera; Oliveira, Mário; Rocha, Isabel

2017-10-01

Knowledge of the physiology underlying the autonomic nervous system is pivotal for understanding autonomic dysfunction in clinical practice. Autonomic dysfunction may result from primary modifications of the autonomic nervous system or be secondary to a wide range of diseases that cause severe morbidity and mortality. Together with a detailed history and physical examination, laboratory assessment of autonomic function is essential for the analysis of various clinical conditions and the establishment of effective, personalized and precise therapeutic schemes. This review summarizes the main aspects of autonomic medicine that constitute the background of cardiovascular autonomic dysfunction. Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Autonomic Neuropathy—a Prospective Cohort Study of Symptoms and E/I Ratio in Normal Glucose Tolerance, Impaired Glucose Tolerance, and Type 2 Diabetes

Directory of Open Access Journals (Sweden)

Malin Zimmerman

2018-03-01

Full Text Available BackgroundAutonomic neuropathy in diabetes, in addition to causing a range of symptoms originating from the autonomic nervous system, may increase cardiovascular morbidity. Our aim was to study the progression of autonomic neuropathy, based on symptom score and evaluation of an autonomic test, in persons with normal and impaired glucose tolerance and in patients with type 2 diabetes (T2D.MethodsParticipants were recruited in 2003/2004 with a follow-up in 2014. The participants’ glucose tolerance was categorized using oral glucose tolerance tests. Symptoms were evaluated using an autonomic symptom score (ASS, ECG was used to test cardiac autonomic function based on the expiration/inspiration ratio (E/I ratio, and blood samples were taken on both occasions.ResultsASSs were higher at follow-up in the T2D patients than in the normal glucose tolerance group (mean 1.21 ± 1.30 vs. 0.79 ± 0.7; p < 0.05. E/I ratio did not deteriorate more than could be expected as an aging effect in well-controlled T2D. No relationship was found between E/I ratio and HbA1c or ASS.ConclusionThe presence of autonomic symptoms increased over time in T2D patients, but the symptoms did not correlate with the E/I ratio in this metabolically well-controlled cohort. ASSs can be a useful clinical tool when assessing the progression of autonomic dysfunction in patients with abnormal glucose metabolism.

Cumulative stress and autonomic dysregulation in a community sample.

Science.gov (United States)

Lampert, Rachel; Tuit, Keri; Hong, Kwang-Ik; Donovan, Theresa; Lee, Forrester; Sinha, Rajita

2016-05-01

Whether cumulative stress, including both chronic stress and adverse life events, is associated with decreased heart rate variability (HRV), a non-invasive measure of autonomic status which predicts poor cardiovascular outcomes, is unknown. Healthy community dwelling volunteers (N = 157, mean age 29 years) participated in the Cumulative Stress/Adversity Interview (CAI), a 140-item event interview measuring cumulative adversity including major life events, life trauma, recent life events and chronic stressors, and underwent 24-h ambulatory ECG monitoring. HRV was analyzed in the frequency domain and standard deviation of NN intervals (SDNN) calculated. Initial simple regression analyses revealed that total cumulative stress score, chronic stressors and cumulative adverse life events (CALE) were all inversely associated with ultra low-frequency (ULF), very low-frequency (VLF) and low-frequency (LF) power and SDNN (all p accounting for additional appreciable variance. For VLF and LF, both total cumulative stress and chronic stress significantly contributed to the variance alone but were not longer significant after adjusting for race and health behaviors. In summary, total cumulative stress, and its components of adverse life events and chronic stress were associated with decreased cardiac autonomic function as measured by HRV. Findings suggest one potential mechanism by which stress may exert adverse effects on mortality in healthy individuals. Primary preventive strategies including stress management may prove beneficial.

Capturing the cardiac effects of racial discrimination: Do the effects "keep going"?

Science.gov (United States)

Hoggard, Lori S; Hill, LaBarron K; Gray, DeLeon L; Sellers, Robert M

2015-08-01

Racial discrimination negatively impacts cardiac functioning, but few studies examine the more distal cardiac effects of racial discrimination experiences. The present study examined the momentary and prolonged impact of lab-based intergroup and intragroup racial discrimination on heart rate variability (HRV) and heart rate (HR) in a sample (N = 42) of African American (AA) women across two days. On day one, the women were exposed to simulated racial discrimination from either a European American (EA) or AA confederate in the lab. On day two, the women returned to the lab for additional physiological recording and debriefing. Women insulted by the EA confederate exhibited lower HRV on day one and marginally lower HRV on day two. These women also exhibited marginally higher HR on day two. The HRV and HR effects on day two were not mediated by differences in perseveration about the stressor. The findings indicate that racial discrimination - particularly intergroup racial discrimination - may have both momentary and prolonged effects on cardiac activity in AAs. Copyright © 2015 Elsevier B.V. All rights reserved.

Physiology of school burnout in medical students: Hemodynamic and autonomic functioning

Directory of Open Access Journals (Sweden)

Ross W. May

2016-09-01

Full Text Available This study investigated the relationship between burnout and hemodynamic and autonomic functioning in both medical students (N = 55 and premedical undergraduate students (N = 77. Questionnaires screened for health related issues and assessed school burnout and negative affect symptomatology (anxiety and depression. Continuous beat-to-beat blood pressure (BP through finger plethysmography and electrocardiogram (ECG monitoring was conducted during conditions of baseline and cardiac stress induced via the cold pressor task to produce hemodynamic, heart rate variability, and blood pressure variability indices. Independent sample t-tests demonstrated that medical students had significantly higher school burnout scores compared to their undergraduate counterparts. Controlling for age, BMI, anxiety and depressive symptoms, multiple regression analyses indicated that school burnout was a stronger predictor of elevated hemodynamics (blood pressure, decreased heart rate variability, decreased markers of vagal activity and increased markers of sympathetic tone at baseline for medical students than for undergraduates. Analyses of physiological values collected during the cold pressor task indicated greater cardiac hyperactivity for medical students than for undergraduates. The present study supports previous research linking medical school burnout to hemodynamic and autonomic functioning, suggests biomarkers for medical school burnout, and provides evidence that burnout may be implicated as a physiological risk factor in medical students. Study limitations and potential intervention avenues are discussed.

Cardiac Autonomic Nervous System Activation and Metabolic Profile in Young Children : The ABCD Study

NARCIS (Netherlands)

Vrijkotte, Tanja G M; van den Born, Bert-Jan H; Hoekstra, Christine M C A; Gademan, Maaike G J; van Eijsden, Manon; de Rooij, Susanne R; Twickler, Marcel T B

2015-01-01

BACKGROUND: In adults, increased sympathetic and decreased parasympathetic nervous system activity are associated with a less favorable metabolic profile. Whether this is already determined at early age is unknown. Therefore, we aimed to assess the association between autonomic nervous system

Sudden cardiac death in multiple sclerosis caused by active demyelination of the medulla oblongata

NARCIS (Netherlands)

Hengstman, G.J.D.; Kusters, B.

2011-01-01

Cardiovascular autonomic dysfunction is not uncommon in multiple sclerosis (MS) and is related to the involvement of the vegetative areas of cardiac innervations in the medulla oblongata. It has been suggested that this may contribute to the occurrence of sudden death in MS. In this case report, we

Autonomic Dysfunction in Muscular Dystrophy: A Theoretical Framework for Muscle Reflex Involvement

Directory of Open Access Journals (Sweden)

Scott Alan Smith

2014-02-01

Full Text Available Muscular dystrophies are a heterogeneous group of genetically inherited disorders whose most prominent clinical feature is progressive degeneration of skeletal muscle. In several forms of the disease, the function of cardiac muscle is likewise affected. The primary defect in this group of diseases is caused by mutations in myocyte proteins important to cellular structure and/or performance. That being stated, a growing body of evidence suggests that the development of autonomic dysfunction may secondarily contribute to the generation of skeletal and cardio-myopathy in muscular dystrophy. Indeed, abnormalities in the regulation of both sympathetic and parasympathetic nerve activity have been reported in a number of muscular dystrophy variants. However, the mechanisms mediating this autonomic dysfunction remain relatively unknown. An autonomic reflex originating in skeletal muscle, the exercise pressor reflex, is known to contribute significantly to the control of sympathetic and parasympathetic activity when stimulated. Given the skeletal myopathy that develops with muscular dystrophy, it is logical to suggest that the function of this reflex might also be abnormal with the pathogenesis of disease. As such, it may contribute to or exacerbate the autonomic dysfunction that manifests. This possibility along with a basic description of exercise pressor reflex function in health and disease are reviewed. A better understanding of the mechanisms that possibly underlie autonomic dysfunction in muscular dystrophy may not only facilitate further research but could also lead to the identification of new therapeutic targets for the treatment of muscular dystrophy.

Cardiac CT for planning redo cardiac surgery: effect of knowledge-based iterative model reconstruction on image quality

International Nuclear Information System (INIS)

Oda, Seitaro; Weissman, Gaby; Weigold, W. Guy; Vembar, Mani

2015-01-01

The purpose of this study was to investigate the effects of knowledge-based iterative model reconstruction (IMR) on image quality in cardiac CT performed for the planning of redo cardiac surgery by comparing IMR images with images reconstructed with filtered back-projection (FBP) and hybrid iterative reconstruction (HIR). We studied 31 patients (23 men, 8 women; mean age 65.1 ± 16.5 years) referred for redo cardiac surgery who underwent cardiac CT. Paired image sets were created using three types of reconstruction: FBP, HIR, and IMR. Quantitative parameters including CT attenuation, image noise, and contrast-to-noise ratio (CNR) of each cardiovascular structure were calculated. The visual image quality - graininess, streak artefact, margin sharpness of each cardiovascular structure, and overall image quality - was scored on a five-point scale. The mean image noise of FBP, HIR, and IMR images was 58.3 ± 26.7, 36.0 ± 12.5, and 14.2 ± 5.5 HU, respectively; there were significant differences in all comparison combinations among the three methods. The CNR of IMR images was better than that of FBP and HIR images in all evaluated structures. The visual scores were significantly higher for IMR than for the other images in all evaluated parameters. IMR can provide significantly improved qualitative and quantitative image quality at in cardiac CT for planning of reoperative cardiac surgery. (orig.)

Quantifying the effect of autonomous adaptation to global river flood projections: application to future flood risk assessments

Science.gov (United States)

Kinoshita, Youhei; Tanoue, Masahiro; Watanabe, Satoshi; Hirabayashi, Yukiko

2018-01-01

This study represents the first attempt to quantify the effects of autonomous adaptation on the projection of global flood hazards and to assess future flood risk by including this effect. A vulnerability scenario, which varies according to the autonomous adaptation effect for conventional disaster mitigation efforts, was developed based on historical vulnerability values derived from flood damage records and a river inundation simulation. Coupled with general circulation model outputs and future socioeconomic scenarios, potential future flood fatalities and economic loss were estimated. By including the effect of autonomous adaptation, our multimodel ensemble estimates projected a 2.0% decrease in potential flood fatalities and an 821% increase in potential economic losses by 2100 under the highest emission scenario together with a large population increase. Vulnerability changes reduced potential flood consequences by 64%-72% in terms of potential fatalities and 28%-42% in terms of potential economic losses by 2100. Although socioeconomic changes made the greatest contribution to the potential increased consequences of future floods, about a half of the increase of potential economic losses was mitigated by autonomous adaptation. There is a clear and positive relationship between the global temperature increase from the pre-industrial level and the estimated mean potential flood economic loss, while there is a negative relationship with potential fatalities due to the autonomous adaptation effect. A bootstrapping analysis suggests a significant increase in potential flood fatalities (+5.7%) without any adaptation if the temperature increases by 1.5 °C-2.0 °C, whereas the increase in potential economic loss (+0.9%) was not significant. Our method enables the effects of autonomous adaptation and additional adaptation efforts on climate-induced hazards to be distinguished, which would be essential for the accurate estimation of the cost of adaptation to

Asymptomatic ST-depression during exercise testing in children and adolescents with type 1 diabetes mellitus and autonomic dysfunction

Directory of Open Access Journals (Sweden)

Dmitry Nikitich Laptev

2015-04-01

Full Text Available Aim. The aim of this study was to investigate cardiac autonomic function as assessed by ST dynamics during and post-exercise in children and adolescents with type 1 diabetes mellitus (T1DM. Materials and methods. The study included 71 young patients with T1DM. The patients were aged 9?18 years and had no history of macrovascular disease or renal disease, including microalbuminuria. Cardiac autonomic function was assessed using cardiovascular tests and 24-h ECG monitoring with automatic calculation of QT interval and heart rate variability parameters. Each patient underwent the physical working capacity 170 test. Results. The prevalence of cardiovascular autonomic neuropathy (CAN was 30.9%. The frequency of asymptomatic ST-segment depression increased during exercise in 10 (45.5% patients with CAN (CAN+ compared with 9 (18.4% patients without CAN (CAN-; p=0.042. During the recovery period, asymptomatic ST-segment depression was present in the first minute in 8 (36.4% CAN+ patients compared with 1 (2% CAN- patient (p=0.0003 and in the second minute in 5 (22.7% CAN+ patients compared with 1 (2% CAN- patient (p=0.0095. Conclusion. Children and adolescents with T1DM and impaired autonomic function have increased prevalence of asymptomatic ST-segment depression during and post-exercise. The presence of cardiovascular risk factors in children and adolescents with T1DM and CAN may contribute to the increased cardiovascular morbidity and mortality during adulthood in patients with T1DM.

Asymptomatic ST-depression during exercise testing in children and adolescents with type 1 diabetes mellitus and autonomic dysfunction

Directory of Open Access Journals (Sweden)

Dmitry Nikitich Laptev

2015-04-01

Full Text Available Aim. The aim of this study was to investigate cardiac autonomic function as assessed by ST dynamics during and post-exercise in children and adolescents with type 1 diabetes mellitus (T1DM.Materials and methods. The study included 71 young patients with T1DM. The patients were aged 9–18 years and had no history of macrovascular disease or renal disease, including microalbuminuria. Cardiac autonomic function was assessed using cardiovascular tests and 24-h ECG monitoring with automatic calculation of QT interval and heart rate variability parameters. Each patient underwent the physical working capacity 170 test.Results. The prevalence of cardiovascular autonomic neuropathy (CAN was 30.9%. The frequency of asymptomatic ST-segment depression increased during exercise in 10 (45.5% patients with CAN (CAN+ compared with 9 (18.4% patients without CAN (CAN-; p=0.042. During the recovery period, asymptomatic ST-segment depression was present in the first minute in 8 (36.4% CAN+ patients compared with 1 (2% CAN- patient (p=0.0003 and in the second minute in 5 (22.7% CAN+ patients compared with 1 (2% CAN- patient (p=0.0095.Conclusion. Children and adolescents with T1DM and impaired autonomic function have increased prevalence of asymptomatic ST-segment depression during and post-exercise. The presence of cardiovascular risk factors in children and adolescents with T1DM and CAN may contribute to the increased cardiovascular morbidity and mortality during adulthood in patients with T1DM.

Diet and exercise training reduce blood pressure and improve autonomic modulation in women with prehypertension.

Science.gov (United States)

Sales, Allan R K; Silva, Bruno M; Neves, Fabricia J; Rocha, Natália G; Medeiros, Renata F; Castro, Renata R T; Nóbrega, Antonio C L

2012-09-01

Despite mortality from heart disease has been decreasing, the decline in death in women remains lower than in men. Hypertension (HT) is a major risk factor for cardiovascular disease. Therefore, approaches to prevent or delay the onset of HT would be valuable in women. Given this background, we investigated the effect of diet and exercise training on blood pressure (BP) and autonomic modulation in women with prehypertension (PHT). Ten women with PHT (39 ± 6 years, mean ± standard deviation) and ten with normotension (NT) (35 ± 11 years) underwent diet and exercise training for 12 weeks. Autonomic modulation was assessed through heart rate (HR) and systolic BP (SBP) variability, using time and frequency domain analyses. At preintervention, women with PHT had higher SBP (PHT: 128 ± 7 vs. NT: 111 ± 6 mmHg, p 0.05). Moreover, reduction in SBP was associated with augmentation in SDNN (r = -0.46, p diet and exercise training reduced SBP in women with PHT, and this was associated with augmentation in parasympathetic and probably reduction in sympathetic cardiac modulation.

Temperature effects on aerobic scope and cardiac performance of European perch (Perca fluviatilis).

Science.gov (United States)

Jensen, Denise Lyager; Overgaard, Johannes; Wang, Tobias; Gesser, Hans; Malte, Hans

2017-08-01

Several recent studies have highlighted how impaired cardiac performance at high temperatures and in hypoxia may compromise the capacity for oxygen transport. Thus, at high temperatures impaired cardiac capacity is proposed to reduce oxygen transport to a degree that lowers aerobic scope and compromises thermal tolerance (the oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis). To investigate this hypothesis, we measured aerobic and cardiac performance of a eurythermal freshwater teleost, the European perch (Perca fluviatilis). Rates of oxygen consumption were measured during rest and activity at temperatures between 5°C and 27°C, and we evaluated cardiac function by in vivo measurements of heart rate and in vitro studies to determine contractility of myocardial strips. Aerobic scope increased progressively from 5°C to 21°C, after which it levelled off. Heart rate showed a similar response. We found little difference between resting and active heart rate at high temperature suggesting that increased cardiac scope during activity is primarily related to changes in stroke volume. To examine the effects of temperature on cardiac capacity, we measured isometric force development in electrically paced myocardial preparations during different combinations of temperature, pacing frequency, oxygenation and adrenergic stimulation. The force-frequency product increased markedly upon adrenergic stimulation at 21 and 27°C (with higher effects at 21°C) and the cardiac preparations were highly sensitive to hypoxia. These findings suggest that at (critically) high temperatures, cardiac output may diminish due to a decreased effect of adrenergic stimulation and that this effect may be further exacerbated if the heart becomes hypoxic. Hence cardiac limitations may contribute to the inability to increase aerobic scope at high temperatures in the European perch (Perca fluviatilis). Copyright © 2017 Elsevier Ltd. All rights reserved.

The Effect of Levetiracetam Therapy on the Autonomous Nerve System in Epilepsy Patients

Directory of Open Access Journals (Sweden)

Kazim Ekmekci

2013-10-01

Full Text Available Aim: It was aimed to research the effects of levetiracetam on some autonomic functions by comparing autonomous nerve system tests in epilepsy patients using levetiracetam monotherapy with the tests of the healthy volunteers who don’t use drug.   Material and Method: Fourty-one patients diagnosed with partial epilepsy using levetiracetam were included in this study. Control group was selected from 35 healthy volunteers who don’t have epilepsy. RR interval variation (RRIV, valsalva, and tilt tests were applied to patient and control groups in order to assess the autonomous nerve system functions. Results: No statistically-significant differences were found in the results of RRIV, valsalva, and tilt tests in patients in comparison with the control group (p>0.05. No statistical significances weren’t also observed when the results of upright position and the postural blood pressure changes were compared with the control group (p>0.05. Discussion: Our findings had shown that using levetiracetam therapy had no effect on the responses of heart rate and blood pressure in epilepsy patients.

Effects of alpha-glucosylhesperidin on the peripheral body temperature and autonomic nervous system.

Science.gov (United States)

Takumi, Hiroko; Fujishima, Noboru; Shiraishi, Koso; Mori, Yuka; Ariyama, Ai; Kometani, Takashi; Hashimoto, Shinichi; Nadamoto, Tomonori

2010-01-01

We studied the effects of alpha-glucosylhesperidin (G-Hsp) on the peripheral body temperature and autonomic nervous system in humans. We first conducted a survey of 97 female university students about excessive sensitivity to the cold; 74% of them replied that they were susceptible or somewhat susceptible to the cold. We subsequently conducted a three-step experiment. In the first experiment, G-Hsp (500 mg) was proven to prevent a decrease in the peripheral body temperature under an ambient temperature of 24 degrees C. In the second experiment, a warm beverage containing G-Hsp promoted blood circulation and kept the finger temperature higher for a longer time. We finally used a heart-rate variability analysis to study whether G-Hsp changed the autonomic nervous activity. The high-frequency (HF) component tended to be higher, while the ratio of the low-frequency (LF)/HF components tended to be lower after the G-Hsp administration. These results suggest that the mechanism for temperature control by G-Hsp might involve an effect on the autonomic nervous system.

Novel therapeutic effects of sesamin on diabetes-induced cardiac dysfunction

Science.gov (United States)

Thuy, Tran Duong; Phan, Nam Nhut; Wang, Chih-Yang; Yu, Han-Gang; Wang, Shu-Yin; Huang, Pung-Ling; Do, Yi-Yin; Lin, Yen-Chang

2017-01-01

Diabetes is a risk factor that increases the occurrence and severity of cardiovascular events. Cardiovascular complications are the leading cause of mortality of 75% of patients with diabetes >40 years old. Sesamin, the bioactive compound extracted from Sesamum indicum, is a natural compound that has diverse beneficial effects on hypoglycemia and reducing cholesterol. The aim of this study is to investigate sesamin effects to diabetes-inducing cardiac hypertrophy. In the present study bioinformatics analysis demonstrated cardiac hypertrophy signaling may be the most important pathway for upregulating genes in sesamin-treated groups. To verify the bioinformatics prediction, sesamin was used as the main bioactive compound to attenuate the impact of diabetes induced by streptozotocin (STZ) on cardiac function in a rat model. The results revealed that oral administration of sesamin for 4 weeks (100 and 200 mg/kg body weight) marginally improved blood glucose levels, body weight and significantly ameliorated the effects on heart rate and blood pressure in rats with type 1 diabetes relative to control rats. The QT interval of sesamin was also reduced relative to the control group. The findings indicated that sesamin has potential cardioprotective effects in the STZ-induced diabetes model. This suggested that this can be used as a novel treatment for patients with diabetes with cardiac dysfunction complication. PMID:28358428

Low to high frequency ratio of heart rate variability spectra fails to describe sympatho-vagal balance in cardiac patients.

Science.gov (United States)

Milicević, Goran

2005-06-01

Heart rate variability (HRV) reflects an influence of autonomic nervous system on heart work. In healthy subjects, ratio between low and high frequency components (LF/HF ratio) of HRV spectra represents a measure of sympatho-vagal balance. The ratio was defined by the authorities as an useful clinical tool, but it seems that it fails to summarise sympatho-vagal balance in a clinical setting. Value of the method was re-evaluated in several categories of cardiac patients. HRV was analysed from 24-hour Holter ECGs in 132 healthy subjects, and 2159 cardiac patients dichotomised by gender, median of age, diagnosis of myocardial infarction or coronary artery surgery, left ventricular systolic function and divided by overall HRV into several categories. In healthy subjects, LF/HF ratio correlated with overall HRV negatively, as expected. The paradoxical finding was obtained in cardiac patients; the lower the overall HRV and the time-domain indices of vagal modulation activity were the lower the LF/HF ratio was. If used as a measure of sympatho-vagal balance, long-term recordings of LF/HF ratio contradict to clinical finding and time-domain HRV indices in cardiac patients. The ratio cannot therefore be used as a reliable marker of autonomic activity in a clinical setting.

Structural Discrimination and Autonomous Vehicles

DEFF Research Database (Denmark)

Liu, Hin-Yan

2016-01-01

This paper examines the potential for structural discrimination to be woven into the fabric of autonomous vehicle developments, which remain underexplored and undiscussed. The prospect for structural discrimination arises as a result of the coordinated modes of autonomous vehicle behaviour...... individual identity, and potentially relative worth, to autonomous vehicles engaging in a crash damage calculus. At the risk of introducing these ideas into the development of autonomous vehicles, this paper hopes to spark a debate to foreclose these eventualities....... that is prescribed by its code. This leads to the potential for individuated outcomes to be networked and thereby multiplied consistently to any number of vehicles implementing such a code. The aggregated effects of such algorithmic policy preferences will thus cumulate in the reallocation of benefits and burdens...

Efficacy and safety of aldose reductase inhibitor for the treatment of diabetic cardiovascular autonomic neuropathy: systematic review and meta-analysis.

Directory of Open Access Journals (Sweden)

Xin Hu

Full Text Available BACKGROUND: Aldose reductase inhibitors (ARIs can block the metabolism of the polyol pathway, and have been used to slow or reverse the progression of diabetic cardiovascular autonomic neuropathy (DCAN. The purpose of this study was to review the effectiveness and safety of ARIs in the treatment of DCAN as determined by five cardiac autonomic neuropathy function tests. METHODS: CENTRAL, MEDLINE, EMBASE, Scopus databases (inception to May 2012 were searched to identify randomized controlled trials (RCTs and non-randomized controlled trials (non-RCTs investigating ARIs for the treatment of DCAN with an English-language restriction. The data were analyzed using RevMan 5.0, and the heterogeneity between the trials was evaluated using the Cochrane's Q-test as well as the I² test. The type of model (random or fixed used for analysis was based on heterogeneity. Weighted mean differences (WMD with 95% confidence intervals (CI were computed for the five cardiac automatic neuropathy function tests to evaluate the effects. RESULTS: Ten articles met the prerequisites for this review. Analysis of the results showed that ARIs significantly improved function in at least three of the five automatic neuropathy tests, including the resting heart rate variation coefficients (WMD = 0.25, 95%CI 0.02 to 0.48, P = 0.040; the 30∶15 ratio (WMD = 0.06, 95%CI 0.01 to 0.10, P = 0.010 and the postural systolic blood pressure change (WMD = -5.94, 95%CI -7.31 to -4.57, P = 0.001. The expiration/inspiration ratio showed a marginally significant benefit (WMD = 0.05, 95%CI 0.00 to 0.09, P = 0.040. Glycaemic control was not significantly affected by ARIs. Adverse effects of ARIs except for Tolerestat were minimal. CONCLUSIONS: Based on these results, we conclude that ARIs could ameliorate cardiac automatic neuropathy especially mild or asymptomatic DCAN but need further investigation.

Evaluation of cardiac denervation in patients with long-standing diabetes

International Nuclear Information System (INIS)

Khurram, M.; Khar, Hamama-tul-Bushra; Malik, M.F. Fazal-ur-Rehman; Javed, S.; Hassan, Z.; Minhas, Z.; Goraya, M.F.; Shakoor, A.

2002-01-01

Objective: Evaluation of cardiac autonomic dysfunction in long-standing diabetics, comparing patients treated with insulin and oral hypo glycemic agents. Design: Observational and comparative study between two treatment groups. Place and Duration of Study: At department of Medicine, Pakistan Institute of Medical Sciences, Islamabad, for 6 months. Subjects and Methods: Fifty diabetic patients of about 10 years illness were studied. Patients were divided into two groups, Group 1(13 males, 12 females; mean age 33.08 years) included those who received insulin, and Group II patients (12 males, 13 females; mean age 54.68 years) who received oral hypo glycemic agents for their diabetic illness. Evaluation of cardiac denervation in both the groups was done in terms of presence of resting tachycardia, loss of sinus arrhythmia and abnormalities of Valsava response. Results: At least some form of cardiac denervation was present in 62% of total subjects. 48% of Group I and 76 % of Group II patients. A significantly high number of patients treated with oral hypo glycemic agents had evidence of cardiac denervation when compared with patients who were treated with insulin (p < 0.05). Conclusion: Cardiac denervation is common in long-standing diabetics specifically in those treated with oral hypo glycemic agents. (author)

Autonomous Landing on Moving Platforms

KAUST Repository

Mendoza Chavez, Gilberto

2016-08-01

This thesis investigates autonomous landing of a micro air vehicle (MAV) on a nonstationary ground platform. Unmanned aerial vehicles (UAVs) and micro air vehicles (MAVs) are becoming every day more ubiquitous. Nonetheless, many applications still require specialized human pilots or supervisors. Current research is focusing on augmenting the scope of tasks that these vehicles are able to accomplish autonomously. Precise autonomous landing on moving platforms is essential for self-deployment and recovery of MAVs, but it remains a challenging task for both autonomous and piloted vehicles. Model Predictive Control (MPC) is a widely used and effective scheme to control constrained systems. One of its variants, output-feedback tube-based MPC, ensures robust stability for systems with bounded disturbances under system state reconstruction. This thesis proposes a MAV control strategy based on this variant of MPC to perform rapid and precise autonomous landing on moving targets whose nominal (uncommitted) trajectory and velocity are slowly varying. The proposed approach is demonstrated on an experimental setup.

Effects of teacher autonomy support and students' autonomous motivation on learning in physical education.

Science.gov (United States)

Shen, Bo; McCaughtry, Nate; Martin, Jeffrey; Fahlman, Mariane

2009-03-01

This study applied self-determination theory to investigate the effects of students' autonomous motivation and their perceptions of teacher autonomy support on need satisfaction adjustment, learning achievement, and cardiorespiratory fitness over a 4-month personal conditioning unit. Participants were 253 urban adolescents (121 girls and 132 boys, ages = 12-14 years). Based on a series of multiple regression analyses, perceived autonomy support by teachers significantly predicted students'need satisfaction adjustment and led to learning achievement, especially for students who were not autonomously motivated to learn in physical education. In turn, being more autonomous was directly associated with cardiorespiratory fitness enhancement. The findings suggest that shifts in teaching approaches toward providing more support for students' autonomy and active involvement hold promise for enhancing learning.

Premature Ventricular Contraction Coupling Interval Variability Destabilizes Cardiac Neuronal and Electrophysiological Control: Insights From Simultaneous Cardioneural Mapping.

Science.gov (United States)

Hamon, David; Rajendran, Pradeep S; Chui, Ray W; Ajijola, Olujimi A; Irie, Tadanobu; Talebi, Ramin; Salavatian, Siamak; Vaseghi, Marmar; Bradfield, Jason S; Armour, J Andrew; Ardell, Jeffrey L; Shivkumar, Kalyanam

2017-04-01

Variability in premature ventricular contraction (PVC) coupling interval (CI) increases the risk of cardiomyopathy and sudden death. The autonomic nervous system regulates cardiac electrical and mechanical indices, and its dysregulation plays an important role in cardiac disease pathogenesis. The impact of PVCs on the intrinsic cardiac nervous system, a neural network on the heart, remains unknown. The objective was to determine the effect of PVCs and CI on intrinsic cardiac nervous system function in generating cardiac neuronal and electric instability using a novel cardioneural mapping approach. In a porcine model (n=8), neuronal activity was recorded from a ventricular ganglion using a microelectrode array, and cardiac electrophysiological mapping was performed. Neurons were functionally classified based on their response to afferent and efferent cardiovascular stimuli, with neurons that responded to both defined as convergent (local reflex processors). Dynamic changes in neuronal activity were then evaluated in response to right ventricular outflow tract PVCs with fixed short, fixed long, and variable CI. PVC delivery elicited a greater neuronal response than all other stimuli ( P <0.001). Compared with fixed short and long CI, PVCs with variable CI had a greater impact on neuronal response ( P <0.05 versus short CI), particularly on convergent neurons ( P <0.05), as well as neurons receiving sympathetic ( P <0.05) and parasympathetic input ( P <0.05). The greatest cardiac electric instability was also observed after variable (short) CI PVCs. Variable CI PVCs affect critical populations of intrinsic cardiac nervous system neurons and alter cardiac repolarization. These changes may be critical for arrhythmogenesis and remodeling, leading to cardiomyopathy. © 2017 American Heart Association, Inc.

Effect of Social Intolerance on Psychological Distress in Cardiac Patients

International Nuclear Information System (INIS)

Zonash, R.; Arouj, K.

2017-01-01

Background: The patients with diverse cardiac issues and physical illness experience different levels of social intolerance, depression, anxiety and stress. Objectives: To explore the relationship between social intolerance and psychological distress among cardiac patients and investigate the effect of different type of cardiac illness, its duration and physical symptoms on social intolerance and psychological distress. Study design, settings and duration: Cross-sectional study, conducted at Benazir Bhutto Hospital (BBH), Rawalpindi Institute of Cardiology (RIC), Hearts International Hospital (HIH) and Pakistan Institute of Medical Sciences (PIMS) from September-December, 2014. Patients and Methods: The sample size of 180 adult cardiac patients was collected. These patients were selected from the cardiac units of 4 hospitals of Rawalpindi using purposive sampling. Social intolerance was assessed using Frustration Discomfort Scale (FDS), distress was assessed using depression anxiety and stress scale (DASS) Results: Out of 180 patients, 53.3 percent were males and 46.7 percent females. Their ages ranged from 20 to 60 years. Results revealed significant discomfort intolerance, (p < 0.01) entitlement (p < 0.05) and emotional intolerance (p < 0.01) in these patients. There was 45 percent variance in depression, while discomfort intolerance (p < 0.01) and achievement frustration (p< 0.01) showed 35 percent variance in anxiety. Conclusion: Cardiac patients suffer from major emotional distress.(author)

[Heart rate variability as a method of assessing the autonomic nervous system in polycystic ovary syndrome].

Science.gov (United States)

de Sá, Joceline Cássia Ferezini; Costa, Eduardo Caldas; da Silva, Ester; Azevedo, George Dantas

2013-09-01

Polycystic ovary syndrome (PCOS) is an endocrine disorder associated with several cardiometabolic risk factors, such as central obesity, insulin resistance, type 2 diabetes, metabolic syndrome, and hypertension. These factors are associated with adrenergic overactivity, which is an important prognostic factor for the development of cardiovascular disorders. Given the common cardiometabolic disturbances occurring in PCOS women, over the last years studies have investigated the cardiac autonomic control of these patients, mainly based on heart rate variability (HRV). Thus, in this review, we will discuss the recent findings of the studies that investigated the HRV of women with PCOS, as well as noninvasive methods of analysis of autonomic control starting from basic indexes related to this methodology.

The effect of cardiac rehabilitation on anxiety and depression in patients undergoing cardiac bypass graft surgery in Iran

Directory of Open Access Journals (Sweden)

Sharif Farkhondeh

2012-06-01

Full Text Available Abstract Background Many patients experience anxiety and depression after cardiac bypass surgery. The aim of this study was to examine the effect of cardiac rehabilitation on anxiety and depression in patients undergoing coronary artery bypass grafting in hospitals affiliated to Shiraz University of Medical Sciences in southern Iran. Methods For this randomized controlled trial, 80 patients who met the inclusion criteria were recruited and randomly assigned to case and control groups. Anxiety was measured with the Spielberger Anxiety Scale and depression was measured using Beck’s Depression Inventory at three points in time: on discharge from the hospital, immediately after the intervention, and 2 months after cardiac rehabilitation. After measuring anxiety and depression in both groups upon discharge, the experimental group participated in 8 cardiac rehabilitation sessions over a 4-week period. The control group received only the routine follow-up care. Results There was a statistically significant difference in depression scores between groups at all three time-points (Mean score from 19.6 to 10 in the intervention group and from 19.5 to 14 in the control group, P = 0.0014. However, no significant difference was seen in anxiety scores between the groups (Mean score from 37 to 28 in the intervention group and from 38 to 32 in the control group, P = 0.079. Conclusions Cardiac rehabilitation was effective in reducing depression 2 months after surgery in patients undergoing coronary artery bypass grafting. Trial registration IRCTN201203262812N8

Stress cardiac magnetic resonance imaging provides effective cardiac risk reclassification in patients with known or suspected stable coronary artery disease.

Science.gov (United States)

Shah, Ravi; Heydari, Bobak; Coelho-Filho, Otavio; Murthy, Venkatesh L; Abbasi, Siddique; Feng, Jiazhuo H; Pencina, Michael; Neilan, Tomas G; Meadows, Judith L; Francis, Sanjeev; Blankstein, Ron; Steigner, Michael; di Carli, Marcelo; Jerosch-Herold, Michael; Kwong, Raymond Y

2013-08-06

A recent large-scale clinical trial found that an initial invasive strategy does not improve cardiac outcomes beyond optimized medical therapy in patients with stable coronary artery disease. Novel methods to stratify at-risk patients may refine therapeutic decisions to improve outcomes. In a cohort of 815 consecutive patients referred for evaluation of myocardial ischemia, we determined the net reclassification improvement of the risk of cardiac death or nonfatal myocardial infarction (major adverse cardiac events) incremental to clinical risk models, using guideline-based low (3%) annual risk categories. In the whole cohort, inducible ischemia demonstrated a strong association with major adverse cardiac events (hazard ratio=14.66; Pstatistic, 0.81-0.86; P=0.04; adjusted hazard ratio=7.37; PStress cardiac magnetic resonance imaging effectively reclassifies patient risk beyond standard clinical variables, specifically in patients at moderate to high pretest clinical risk and in patients with previous coronary artery disease. http://www.clinicaltrials.gov. Unique identifier: NCT01821924.

Differential effects of active and passive coping on secretory immunity

NARCIS (Netherlands)

Bosch, JA; de Geus, E.J.C.; Kelder, A.; Veerman, E.C.I.; Hoogstraten, J.; van Nieuw Amerongen, A.

2001-01-01

This study examined the acute immunological effects of two laboratory stressors, expected to evoke distinct patterns of cardiac autonomic activity; namely an "active coping" time-paced memory test, and a "passive coping" stressful video showing surgical operations. We measured salivary S-IgA,

Impaired neural structure and function contributing to autonomic symptoms in congenital central hypoventilation syndrome.

Science.gov (United States)

Harper, Ronald M; Kumar, Rajesh; Macey, Paul M; Harper, Rebecca K; Ogren, Jennifer A

2015-01-01

Congenital central hypoventilation syndrome (CCHS) patients show major autonomic alterations in addition to their better-known breathing deficiencies. The processes underlying CCHS, mutations in the PHOX2B gene, target autonomic neuronal development, with frame shift extent contributing to symptom severity. Many autonomic characteristics, such as impaired pupillary constriction and poor temperature regulation, reflect parasympathetic alterations, and can include disturbed alimentary processes, with malabsorption and intestinal motility dyscontrol. The sympathetic nervous system changes can exert life-threatening outcomes, with dysregulation of sympathetic outflow leading to high blood pressure, time-altered and dampened heart rate and breathing responses to challenges, cardiac arrhythmia, profuse sweating, and poor fluid regulation. The central mechanisms contributing to failed autonomic processes are readily apparent from structural and functional magnetic resonance imaging studies, which reveal substantial cortical thinning, tissue injury, and disrupted functional responses in hypothalamic, hippocampal, posterior thalamic, and basal ganglia sites and their descending projections, as well as insular, cingulate, and medial frontal cortices, which influence subcortical autonomic structures. Midbrain structures are also compromised, including the raphe system and its projections to cerebellar and medullary sites, the locus coeruleus, and medullary reflex integrating sites, including the dorsal and ventrolateral medullary nuclei. The damage to rostral autonomic sites overlaps metabolic, affective and cognitive regulatory regions, leading to hormonal disruption, anxiety, depression, behavioral control, and sudden death concerns. The injuries suggest that interventions for mitigating hypoxic exposure and nutrient loss may provide cellular protection, in the same fashion as interventions in other conditions with similar malabsorption, fluid turnover, or hypoxic exposure.

Impaired Neural Structure and Function Contributing to Autonomic Symptoms in Congenital Central Hypoventilation Syndrome

Directory of Open Access Journals (Sweden)

Ronald M Harper

2015-10-01

Full Text Available Congenital central hypoventilation syndrome (CCHS patients show major autonomic alterations in addition to their better-known breathing deficiencies. The processes underlying CCHS, mutations in the PHOX2B gene, target autonomic neuronal development, with frame shift extent contributing to symptom severity. Many autonomic characteristics, such as impaired pupillary constriction and poor temperature regulation, reflect parasympathetic alterations, and can include disturbed alimentary processes, with malabsorption and intestinal motility dyscontrol. The sympathetic nervous system changes can exert life-threatening outcomes, with dysregulation of sympathetic outflow leading to high blood pressure, time-altered and dampened heart rate and breathing responses to challenges, cardiac arrhythmia, profuse sweating, and poor fluid regulation. The central mechanisms contributing to failed autonomic processes are readily apparent from structural and functional magnetic resonance imaging studies, which reveal substantial cortical thinning, tissue injury, and disrupted functional responses in hypothalamic, hippocampal, posterior thalamic, and basal ganglia sites and their descending projections, as well as insular, cingulate, and medial frontal cortices, which influence subcortical autonomic structures. Midbrain structures are also compromised, including the raphe system and its projections to cerebellar and medullary sites, the locus coeruleus, and medullary reflex integrating sites, including the dorsal and ventrolateral medullary nuclei. The damage to rostral autonomic sites overlaps metabolic, affective and cognitive regulatory regions, leading to hormonal disruption, anxiety, depression, behavioral control, and sudden death concerns. The injuries suggest that interventions for mitigating hypoxic exposure and nutrient loss may provide cellular protection, in the same fashion as interventions in other conditions with similar malabsorption, fluid turnover

Cardiac effects of 3-iodothyronamine: a new aminergic system modulating cardiac function.

Science.gov (United States)

Chiellini, Grazia; Frascarelli, Sabina; Ghelardoni, Sandra; Carnicelli, Vittoria; Tobias, Sandra C; DeBarber, Andrea; Brogioni, Simona; Ronca-Testoni, Simonetta; Cerbai, Elisabetta; Grandy, David K; Scanlan, Thomas S; Zucchi, Riccardo

2007-05-01

3-Iodothyronamine T1AM is a novel endogenous thyroid hormone derivative that activates the G protein-coupled receptor known as trace anime-associated receptor 1 (TAAR1). In the isolated working rat heart and in rat cardiomyocytes, T1AM produced a reversible, dose-dependent negative inotropic effect (e.g., 27+/-5, 51+/-3, and 65+/-2% decrease in cardiac output at 19, 25, and 38 microM concentration, respectively). An independent negative chronotropic effect was also observed. The hemodynamic effects of T1AM were remarkably increased in the presence of the tyrosine kinase inhibitor genistein, whereas they were attenuated in the presence of the tyrosine phosphatase inhibitor vanadate. No effect was produced by inhibitors of protein kinase A, protein kinase C, calcium-calmodulin kinase II, phosphatidylinositol-3-kinase, or MAP kinases. Tissue cAMP levels were unchanged. In rat ventricular tissue, Western blot experiments with antiphosphotyrosine antibodies showed reduced phosphorylation of microsomal and cytosolic proteins after perfusion with synthetic T1AM; reverse transcriptase-polymerase chain reaction experiments revealed the presence of transcripts for at least 5 TAAR subtypes; specific and saturable binding of [125I]T1AM was observed, with a dissociation constant in the low micromolar range (5 microM); and endogenous T1AM was detectable by tandem mass spectrometry. In conclusion, our findings provide evidence for the existence of a novel aminergic system modulating cardiac function.

Effects of plasma viscosity modulation on cardiac function during moderate hemodilution

Directory of Open Access Journals (Sweden)

Chatpun Surapong

2010-01-01

Full Text Available Background : Previous studies have found that increasing plasma viscosity as whole blood viscosity decrease has beneficial effects in microvascular hemodynamics. As the heart couples with systemic vascular network, changes in plasma and blood viscosity during hemodilution determine vascular pressure drop and flow rate, which influence cardiac function. This study aimed to investigate how changes in plasma viscosity affect on cardiac function during acute isovolemic hemodilution. Materials and Methods: Plasma viscosity was modulated by hemodilution of 40% of blood volume with three different plasma expanders (PEs. Dextran 2000 kDa (Dx2M, 6.3 cP and dextran 70 kDa (Dx70, 3.0 cP were used as high and moderate viscogenic PEs, respectively. Polyethylene glycol conjugated with human serum albumin (PEG-HSA, 2.2 cP was used as low viscogenic PE. The cardiac function was assessed using a miniaturized pressure-volume conductance catheter. Results: After hemodilution, pressure dropped to 84%, 79%, and 78% of baseline for Dx2M, Dx70 and PEG-HSA, respectively. Cardiac output markedly increased for Dx2M and PEG-HSA. Dx2M significantly produced higher stroke work relative to baseline and compared to Dx70. Conclusion: Acute hemodilution with PEG-HSA without increasing plasma viscosity provided beneficial effects on cardiac function compared to Dx70, and similar to those measured with Dx2M. Potentially negative effects of increasing peripheral vascular resistance due to the increase in plasma viscosity were prevented.

Effects of High-Dose α-Lipoic Acid on Heart Rate Variability of Type 2 Diabetes Mellitus Patients with Cardiac Autonomic Neuropathy in Korea

Directory of Open Access Journals (Sweden)

Sol Jae Lee

2017-07-01

Full Text Available BackgroundDiabetic cardiac autonomic neuropathy (CAN is one of the important complications of diabetes. It is characterized by reduced heart rate variability (HRV.MethodsIn this randomized, double-blind, placebo-controlled, multicenter trial, 75 patients were randomly assigned to one of two groups. One group (n=41 received α-lipoic acid (ALA at an oral dose of 600 mg/day for the first 12 weeks and then 1,200 mg/day for the next 12 weeks. The other group (n=34 received placebo treatment for 24 weeks. CAN was assessed by measuring HRVs in people with diabetes.ResultsMost of the baseline measures for HRVs were similar between the ALA and placebo groups. Although there were no statistically significant HRV changes in the ALA group compared to the placebo group after 24 weeks of trial, we found a positive tendency in some of the HRV parameters of the ALA group. The standard deviations of normal-to-normal RR intervals in the standing position increased by 1.87 ms in the ALA group but decreased by −3.97 ms in the placebo group (P=0.06. The power spectrum of the low frequency (LF band in the standing position increased by 15.77 ms2 in the ALA group, whereas it declined by −15.04 ms2 in the placebo group (P=0.08. The high frequency/LF ratio in the upright position increased by 0.35 in the ALA group, whereas it declined by −0.42 in the placebo group (P=0.06. There were no differences between the two groups regarding rates of adverse events.ConclusionAlthough a slight improvement tendency was seen in HRV in the ALA group, there were no statistically significant HRV changes in the ALA group compared to the placebo group after 24 weeks of trial. However, the high oral dose of ALA was well-tolerated.

Heart rate variability alters cardiac repolarization and electromechanical dynamics.

Science.gov (United States)

Phadumdeo, Vrishti M; Weinberg, Seth H

2018-04-07

Heart rate continuously varies due to autonomic regulation, stochasticity in pacemaking, and circadian rhythm, collectively termed heart rate variability (HRV), during normal physiological conditions. Low HRV is clinically associated with an elevated risk of cardiac arrhythmias. Alternans, a beat-to-beat alternation in action potential duration (APD) and/or intracellular calcium (Ca) transient, is a well-known risk factor associated with cardiac arrhythmias that is typically studied under conditions of a constant pacing rate, i.e., the absence of HRV. In this study, we investigate the effects of HRV on the interplay between APD, Ca, and electromechanical properties, employing a nonlinear discrete-time map model that governs APD and intracellular Ca cycling with a stochastic pacing period. We find that HRV can decrease variation in APD and peak Ca at fast pacing rates for which alternans is present. Further, increased HRV typically disrupts the alternating pattern for both APD and peak Ca and weakens the correlation between APD and peak Ca, thus decoupling Ca-mediated instabilities from repolarization alternation. We find that the efficacy of these effects is regulated by the sarcoplasmic reticulum Ca uptake rate. Overall, these results demonstrate that HRV disrupts arrhythmogenic alternans and suggests that HRV may be a significant factor in preventing life-threatening arrhythmias. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study

Directory of Open Access Journals (Sweden)

Fatima Dumas Cintra

2014-11-01

Full Text Available Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart® system. Results: A total of 767 participants (461 men with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001. After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.

Multivariate pattern classification reveals autonomic and experiential representations of discrete emotions.

Science.gov (United States)

Kragel, Philip A; Labar, Kevin S

2013-08-01

Defining the structural organization of emotions is a central unresolved question in affective science. In particular, the extent to which autonomic nervous system activity signifies distinct affective states remains controversial. Most prior research on this topic has used univariate statistical approaches in attempts to classify emotions from psychophysiological data. In the present study, electrodermal, cardiac, respiratory, and gastric activity, as well as self-report measures were taken from healthy subjects during the experience of fear, anger, sadness, surprise, contentment, and amusement in response to film and music clips. Information pertaining to affective states present in these response patterns was analyzed using multivariate pattern classification techniques. Overall accuracy for classifying distinct affective states was 58.0% for autonomic measures and 88.2% for self-report measures, both of which were significantly above chance. Further, examining the error distribution of classifiers revealed that the dimensions of valence and arousal selectively contributed to decoding emotional states from self-report, whereas a categorical configuration of affective space was evident in both self-report and autonomic measures. Taken together, these findings extend recent multivariate approaches to study emotion and indicate that pattern classification tools may improve upon univariate approaches to reveal the underlying structure of emotional experience and physiological expression. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Detection of cardiovascular autonomic neuropathy using exercise testing in patients with type 2 diabetes mellitus.

Science.gov (United States)

Banthia, Smriti; Bergner, Daniel W; Chicos, Alexandru B; Ng, Jason; Pelchovitz, Daniel J; Subacius, Haris; Kadish, Alan H; Goldberger, Jeffrey J

2013-01-01

This study investigated autonomic nervous system function in subjects with diabetes during exercise and recovery. Eighteen type 2 diabetics (age 55±2 years) and twenty healthy controls (age 51±1 years) underwent two 16-min bicycle submaximal ECG stress tests followed by 45 min of recovery. During session #2, atropine (0.04 mg/kg) was administered at peak exercise, and the final two minutes of exercise and entire recovery occurred under parasympathetic blockade. Plasma catecholamines were measured throughout. Parasympathetic effect was defined as the difference between a measured parameter at baseline and after parasympathetic blockade. The parasympathetic effect on the RR interval was blunted (P=.004) in diabetic subjects during recovery. Parasympathetic effect on QT-RR slope during early recovery was diminished in the diabetes group (diabetes 0.13±0.02, control 0.21±0.02, P=.03). Subjects with diabetes had a lower heart rate recovery at 1 min (diabetes 18.5±1.9 bpm, control 27.6±1.5 bpm, Pdiabetes, even with minimal evidence of CAN using current methodology, altered cardiac autonomic balance is present and can be detected through an exercise-based assessment for CAN. The early post-exercise recovery period in diabetes was characterized by enhanced sympathoexcitation, diminished parasympathetic reactivation and delay in heart rate recovery. Copyright © 2013 Elsevier Inc. All rights reserved.

Wnt signaling balances specification of the cardiac and pharyngeal muscle fields

Science.gov (United States)

Mandal, Amrita; Holowiecki, Andrew; Song, Yuntao Charlie; Waxman, Joshua S.

2017-01-01

Canonical Wnt/β-catenin (Wnt) signaling plays multiple conserved roles during fate specification of cardiac progenitors in developing vertebrate embryos. Although lineage analysis in ascidians and mice has indicated there is a close relationship between the cardiac second heart field (SHF) and pharyngeal muscle (PM) progenitors, the signals underlying directional fate decisions of the cells within the cardio-pharyngeal muscle field in vertebrates are not yet understood. Here, we examined the temporal requirements of Wnt signaling in cardiac and PM development. In contrast to a previous report in chicken embryos that suggested Wnt inhibits PM development during somitogenesis, we find that in zebrafish embryos Wnt signaling is sufficient to repress PM development during anterior-posterior patterning. Importantly, the temporal sensitivity of dorso-anterior PMs to increased Wnt signaling largely overlaps with when Wnt signaling promotes specification of the adjacent cardiac progenitors. Furthermore, we find that excess early Wnt signaling can cell autonomously promote expansion of the first heart field (FHF) progenitors at the expense of PM and SHF within the anterior lateral plate mesoderm (ALPM). Our study provides insight into an antagonistic developmental mechanism that balances the sizes of the adjacent cardiac and PM progenitor fields in early vertebrate embryos. PMID:28087459

The Effects of Climate Change on Cardiac Health.

Science.gov (United States)

De Blois, Jonathan; Kjellstrom, Tord; Agewall, Stefan; Ezekowitz, Justin A; Armstrong, Paul W; Atar, Dan

2015-01-01

The earth's climate is changing and increasing ambient heat levels are emerging in large areas of the world. An important cause of this change is the anthropogenic emission of greenhouse gases. Climate changes have a variety of negative effects on health, including cardiac health. People with pre-existing medical conditions such as cardiovascular disease (including heart failure), people carrying out physically demanding work and the elderly are particularly vulnerable. This review evaluates the evidence base for the cardiac health consequences of climate conditions, with particular reference to increasing heat exposure, and it also explores the potential further implications. © 2015 S. Karger AG, Basel.

Autonomic headache with autonomic seizures: a case report.

Science.gov (United States)

Ozge, Aynur; Kaleagasi, Hakan; Yalçin Tasmertek, Fazilet

2006-10-01

The aim of the report is to present a case of an autonomic headache associated with autonomic seizures. A 19-year-old male who had had complex partial seizures for 15 years was admitted with autonomic complaints and left hemicranial headache, independent from seizures, that he had had for 2 years and were provoked by watching television. Brain magnetic resonance imaging showed right hippocampal sclerosis and electroencephalography revealed epileptic activity in right hemispheric areas. Treatment with valproic acid decreased the complaints. The headache did not fulfil the criteria for the diagnosis of trigeminal autonomic cephalalgias, and was different from epileptic headache, which was defined as a pressing type pain felt over the forehead for several minutes to a few hours. Although epileptic headache responds to anti-epileptics and the complaints of the present case decreased with antiepileptics, it has been suggested that the headache could be a non-trigeminal autonomic headache instead of an epileptic headache.

Effect of a puzzle on the process of students' learning about cardiac physiology.

Science.gov (United States)

Cardozo, Lais Tono; Miranda, Aline Soares; Moura, Maria José Costa Sampaio; Marcondes, Fernanda Klein

2016-09-01

The aim of the present study was to evaluate the effects of using a puzzle to learn about cardiac physiology. Students were divided into control and game groups. In class 1, the control group had a 2-h theoretical class about cardiac physiology, including a detailed description of the phases of the cardiac cycle, whereas the game group had a 50-min theoretical class without the description of the cardiac cycle. In class 2, the control group did an assessment exercise before an activity with the cardiac puzzle and the game group answered questions after the above-mentioned activity. While solving the puzzle, the students had to describe the cardiac cycle by relating the concepts of heart morphology and physiology. To evaluate short-term learning, the number of wrong answers and grades in the assessment exercise were compared between the control and game groups. To evaluate medium-term learning, we compared the grades obtained by students of the control and game groups in questions about cardiac physiology that formed part of the academic exam. In the assessment exercise, the game group presented a lower number of errors and higher score compared with the control group. In the academic exam, applied after both groups had used the puzzle, there was no difference in the scores obtained by the control and game groups in questions about cardiac physiology. These results showed a positive effect of the puzzle on students' learning about cardiac physiology compared with those not using the puzzle. Copyright © 2016 The American Physiological Society.

Effects of therapeutic touch on anxiety, vital signs, and cardiac dysrhythmia in a sample of Iranian women undergoing cardiac catheterization: a quasi-experimental study.

Science.gov (United States)

Zolfaghari, Mitra; Eybpoosh, Sana; Hazrati, Maryam

2012-12-01

To investigate the effects of Therapeutic Touch (TT) on anxiety, vital signs, and cardiac dysrhythmia in women undergoing cardiac catheterization. It was a quasi-experimental study. The participants had no history of hallucination, anxiety, or other psychological problems. Participants had to be conscious and have attained at least sixth-grade literacy level. Participants were randomly assigned into an intervention group (n = 23; received 10-15 minutes TT), a placebo group (n = 23; received 10-15 minutes simulated touch), and a control group (n = 23; did not receive any therapy). Data were collected using Spielberger's anxiety test, cardiac dysrhythmia checklist, and vital signs recording sheet. Statistical analyses were considered to be significant at α = .05 levels. Sixty-nine women ranging in age from 35 to 65 years participated. TT significantly decreased state anxiety p < 0.0001 but not trait anxiety (p = .88), decreased the incidence of all cardiac dysrhythmias p < 0.0001 except premature ventricular contraction (p = .01), and regulated vital signs p < 0.0001 in the intervention group versus placebo and control group. TT is an effective approach for managing state anxiety, regulating vital signs, and decreasing the incidence of cardiac dysrhythmia during stressful situations, such as cardiac catheterization, in Iranian cardiac patients.

Cardiac Function Remains Impaired Despite Reversible Cardiac Remodeling after Acute Experimental Viral Myocarditis

Directory of Open Access Journals (Sweden)

Peter Moritz Becher

2017-01-01

Full Text Available Background. Infection with Coxsackievirus B3 induces myocarditis. We aimed to compare the acute and chronic phases of viral myocarditis to identify the immediate effects of cardiac inflammation as well as the long-term effects after resolved inflammation on cardiac fibrosis and consequently on cardiac function. Material and Methods. We infected C57BL/6J mice with Coxsackievirus B3 and determined the hemodynamic function 7 as well as 28 days after infection. Subsequently, we analyzed viral burden and viral replication in the cardiac tissue as well as the expression of cytokines and matrix proteins. Furthermore, cardiac fibroblasts were infected with virus to investigate if viral infection alone induces profibrotic signaling. Results. Severe cardiac inflammation was determined and cardiac fibrosis was consistently colocalized with inflammation during the acute phase of myocarditis. Declined cardiac inflammation but no significantly improved hemodynamic function was observed 28 days after infection. Interestingly, cardiac fibrosis declined to basal levels as well. Both cardiac inflammation and fibrosis were reversible, whereas the hemodynamic function remains impaired after healed viral myocarditis in C57BL/6J mice.

The effects of malnutrition on cardiac function in African children.

Science.gov (United States)

Silverman, Jonathan A; Chimalizeni, Yamikani; Hawes, Stephen E; Wolf, Elizabeth R; Batra, Maneesh; Khofi, Harriet; Molyneux, Elizabeth M

2016-02-01

Cardiac dysfunction may contribute to high mortality in severely malnourished children. Our objective was to assess the effect of malnutrition on cardiac function in hospitalised African children. Prospective cross-sectional study. Public referral hospital in Blantyre, Malawi. We enrolled 272 stable, hospitalised children ages 6-59 months, with and without WHO-defined severe acute malnutrition. Cardiac index, heart rate, mean arterial pressure, stroke volume index and systemic vascular resistance index were measured by the ultrasound cardiac output monitor (USCOM, New South Wales, Australia). We used linear regression with generalised estimating equations controlling for age, sex and anaemia. Our primary outcome, cardiac index, was similar between those with and without severe malnutrition: difference=0.22 L/min/m(2) (95% CI -0.08 to 0.51). No difference was found in heart rate or stroke volume index. However, mean arterial pressure and systemic vascular resistance index were lower in children with severe malnutrition: difference=-8.6 mm Hg (95% CI -12.7 to -4.6) and difference=-200 dyne s/cm(5)/m(2) (95% CI -320 to -80), respectively. In this largest study to date, we found no significant difference in cardiac function between hospitalised children with and without severe acute malnutrition. Further study is needed to determine if cardiac function is diminished in unstable malnourished children. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Hypocretin-1 (orexin A) prevents the effects of hypoxia/hypercapnia and enhances the GABAergic pathway from the lateral paragigantocellular nucleus to cardiac vagal neurons in the nucleus ambiguus.

Science.gov (United States)

Dergacheva, O; Philbin, K; Bateman, R; Mendelowitz, D

2011-02-23

Hypocretins (orexins) are hypothalamic neuropeptides that play a crucial role in regulating sleep/wake states and autonomic functions including parasympathetic cardiac activity. We have recently demonstrated stimulation of the lateral paragigantocellular nucleus (LPGi), the nucleus which is thought to play a role in rapid eye movement (REM) sleep control, activates an inhibitory pathway to preganglionic cardiac vagal neurons in the nucleus ambiguus (NA). In this study we test the hypothesis that hypocretin-1 modulates the inhibitory neurotransmission to cardiac vagal neurons evoked by stimulation of the LPGi using whole-cell patch-clamp recordings in an in vitro brain slice preparation from rats. Activation of hypocretin-1 receptors produced a dose-dependent and long-term facilitation of GABAergic postsynaptic currents evoked by electrical stimulation of the LPGi. Hypoxia/hypercapnia diminished LPGi-evoked GABAergic current in cardiac vagal neurons and this inhibition by hypoxia/hypercapnia was prevented by pre-application of hypocretin-1. The action of hypocretin-1 was blocked by the hypocretin-1 receptor antagonist SB-334867. Facilitation of LPGi-evoked GABAergic current in cardiac vagal neurons under both normal condition and during hypoxia/hypercapnia could be the mechanism by which hypocretin-1 affects parasympathetic cardiac function and heart rate during REM sleep. Furthermore, our findings indicate a new potential mechanism that might be involved in the cardiac arrhythmias, bradycardia, and sudden cardiac death that can occur during sleep. Copyright © 2011. Published by Elsevier Ltd.

Short-term results of a 5-week comprehensive cardiac rehabilitation program after first-time myocardial infarction.

Science.gov (United States)

Fallavollita, Luca; Marsili, Bruno; Castelli, Sandro; Cucchi, Francesca; Santillo, Elpidio; Marini, Luciano; Balestrini, Fabrizio

2016-03-01

A prospective single-center interventional cohort study was conducted to evaluate the effects of a 5-week comprehensive cardiac rehabilitation program on terms exercise capacity, quality of life, echocardiographic findings and autonomic modulation after first-time myocardial infarction. We studied 37 consecutive post-myocardial infartion patients (mean age 66 years). All patients began a 5-week cardiac rehabilitation supervised training. The exercise program consisted of 40 minutes of training, three times a week, on a cycle ergometer at 60-80% of the maximal heart rate. At baseline and after training program we analyzed: the distance walked after the Six-Minutes Walking Test (6MWT); quality of life (QoL) assesed using the Psychological General Well-Being Inventory (PGWBI) questionnaire; echocardiographic finding and autonomic balance assesed heart rate variability (HRV). We observed statistically significant improvement in exercise capacity (from 423±94 to 496±13 m; P<0.05). Also we observed statistically significant improvements in the many PGWBI dimensions; particularly, anxiety +5.8% (from 18.11±5.2 to 19.12±4.4); depression +6.0% (from 12.00±3.0 to 12.73±2.4); positive well-being +6% (from 11.55±3.5 to 12.23±4.0); general health +10.3% (from 9.48±3.5 to 10.46±2.87); vitality +6.8% (from 12.96±4.2 to 13.85±4.2). Finally, we observed changes in HRV indices after training program: RR (from 903±169 ms to 952±163 ms; P<0.05), pNN50% (from 4.74±4.89 to 6.23±5.53; P<0.05), in time-domain; LF (from 274±169 to 362±233 ms2; P<0,05); HF (from 214±154 to 314±194 ms2; P<0.05) and LF/HF (from 1.53±0.54 to 1.24±0.47; P<0.05) in frequency-domain. The study suggest that a cardiac rehabilitation program in postmyocardial infarction improves exercise capacity, QoL and autonomic modulation.

Arterial Stiffness and Autonomic Modulation After Free-Weight Resistance Exercises in Resistance Trained Individuals.

Science.gov (United States)

Kingsley, J Derek; Mayo, Xián; Tai, Yu Lun; Fennell, Curtis

2016-12-01

Kingsley, JD, Mayo, X, Tai, YL, and Fennell, C. Arterial stiffness and autonomic modulation after free-weight resistance exercises in resistance trained individuals. J Strength Cond Res 30(12): 3373-3380, 2016-We investigated the effects of an acute bout of free-weight, whole-body resistance exercise consisting of the squat, bench press, and deadlift on arterial stiffness and cardiac autonomic modulation in 16 (aged 23 ± 3 years; mean ± SD) resistance-trained individuals. Arterial stiffness, autonomic modulation, and baroreflex sensitivity (BRS) were assessed at rest and after 3 sets of 10 repetitions at 75% 1-repetition maximum on each exercise with 2 minutes of rest between sets and exercises. Arterial stiffness was analyzed using carotid-femoral pulse wave velocity (cf-PWV). Linear heart rate variability (log transformed [ln] absolute and normalized units [nu] of low-frequency [LF] and high-frequency [HF] power) and nonlinear heart rate complexity (Sample Entropy [SampEn], Lempel-Ziv Entropy [LZEn]) were measured to determine autonomic modulation. BRS was measured by the sequence method. A 2 × 2 repeated measures analysis of variance (ANOVA) was used to analyze time (rest, recovery) across condition (acute resistance exercise, control). There were significant increases in cf-PWV (p = 0.05), heart rate (p = 0.0001), normalized LF (LFnu; p = 0.001), and the LF/HF ratio (p = 0.0001). Interactions were also noted for ln HF (p = 0.006), HFnu (p = 0.0001), SampEn (p = 0.001), LZEn (p = 0.005), and BRS (p = 0.0001) such that they significantly decreased during recovery from the resistance exercise compared with rest and the control. There was no effect on ln total power, or ln LF. These data suggest that a bout of resistance exercise using free-weights increases arterial stiffness and reduces vagal activity and BRS in comparison with a control session. Vagal tone may not be fully recovered up to 30 minutes after a resistance exercise bout.

Serum cortisol concentration with exploratory cut-off values do not predict the effects of hydrocortisone administration in children with low cardiac output after cardiac surgery.

Science.gov (United States)

Verweij, E J; Hogenbirk, Karin; Roest, Arno A W; van Brempt, Ronald; Hazekamp, Mark G; de Jonge, Evert

2012-10-01

Low cardiac output syndrome is common after paediatric cardiac surgery. Previous studies suggested that hydrocortisone administration may improve haemodynamic stability in case of resistant low cardiac output syndrome in critically ill children. This study was set up to test the hypothesis that the effects of hydrocortisone on haemodynamics in children with low cardiac output syndrome depend on the presence of (relative) adrenal insufficiency. A retrospective study was done on paediatric patients who received hydrocortisone when diagnosed with resistant low cardiac output syndrome after paediatric cardiac surgery in the period from 1 November 2005 to 31 December 2008. We studied the difference in effects of treatment with hydrocortisone administration between patients with adrenal insufficiency defined as an exploratory cut-off value of total cortisol of cortisol of ≥ 100 nmol/l. A total of 62 of patients were enrolled, meeting the inclusion criteria for low cardiac output syndrome. Thirty-two patients were assigned to Group 1 (cortisol concentration and those with normal baseline cortisol levels. A cortisol value using an exploratory cut-off value of 100 nmol/l for adrenal insufficiency should not be used as a criterion to treat these patients with hydrocortisone.

Is it time for cardiac innervation imaging?

Energy Technology Data Exchange (ETDEWEB)

Knuuti, J. [Turku Univ., Turku (Finland) Turku PET Center; Sipola, P. [Kuopio Univ., Kuopio (Finland)

2005-03-01

The autonomic nervous system plays an important role in the regulation of cardiac function and the regional distribution of cardiac nerve terminals can be visualized using scintigraphic techniques. The most commonly used tracer is iodine-123-metaiodobenzylguanidine (MIBG) but C-11-hydroxyephedrine has also been used with PET. When imaging with MIBG, the ratio of heart-to-mediastinal counts is used as an index of tracer uptake, and regional distribution is also assessed from tomographic images. The rate of clearance of the tracer can also be measured and indicates the function of the adrenergic system. Innervation imaging has been applied in patients with susceptibility to arrythmias, coronary artery disease, hypertrophic and dilated cardiomyopathy and anthracycline induced cardiotoxicity. Abnormal adrenergic innervation or function appear to exist in many pathophysiological conditions indicating that sympathetic neurons are very susceptible to damage. Abnormal findings in innervation imaging also appear to have significant prognostic value especially in patients with cardiomyopathy. Recently, it has also been shown that innervation imaging can monitor drug-induced changes in cardiac adrenergic activity. Although innervation imaging holds great promise for clinical use, the method has not received wider clinical acceptance. Larger randomized studies are required to confirm the value of innervation imaging in various specific indications.

Effects of the Fourth Ventricle Compression in the Regulation of the Autonomic Nervous System: A Randomized Control Trial

Directory of Open Access Journals (Sweden)

Ana Paula Cardoso-de-Mello-e-Mello-Ribeiro

2015-01-01

Full Text Available Introduction. Dysfunction of the autonomic nervous system is an important factor in the development of chronic pain. Fourth ventricle compression (CV-4 has been shown to influence autonomic activity. Nevertheless, the physiological mechanisms behind these effects remain unclear. Objectives. This study is aimed at evaluating the effects of fourth ventricle compression on the autonomic nervous system. Methods. Forty healthy adults were randomly assigned to an intervention group, on whom CV-4 was performed, or to a control group, who received a placebo intervention (nontherapeutic touch on the occipital bone. In both groups, plasmatic catecholamine levels, blood pressure, and heart rate were measured before and immediately after the intervention. Results. No effects related to the intervention were found. Although a reduction of norepinephrine, systolic blood pressure, and heart rate was found after the intervention, it was not exclusive to the intervention group. In fact, only the control group showed an increment of dopamine levels after intervention. Conclusion. Fourth ventricle compression seems not to have any effect in plasmatic catecholamine levels, blood pressure, or heart rate. Further studies are needed to clarify the CV-4 physiologic mechanisms and clinical efficacy in autonomic regulation and pain treatment.

Hemodynamic and autonomic nervous system responses to mixed meal ingestion in healthy young and old subjects and dysautonomic patients with postprandial hypotension

Science.gov (United States)

Lipsitz, L. A.; Ryan, S. M.; Parker, J. A.; Freeman, R.; Wei, J. Y.; Goldberger, A. L.

1993-01-01

BACKGROUND. Although postprandial hypotension is a common cause of falls and syncope in elderly persons and in patients with autonomic insufficiency, the pathophysiology of this disorder remains unknown. METHODS AND RESULTS. We examined the hemodynamic, splanchnic blood pool, plasma norepinephrine (NE), and heart rate (HR) power spectra responses to a standardized 400-kcal mixed meal in 11 healthy young (age, 26 +/- 5 years) and nine healthy elderly (age, 80 +/- 5 years) subjects and 10 dysautonomic patients with symptomatic postprandial hypotension (age, 65 +/- 16 years). Cardiac and splanchnic blood pools were determined noninvasively by radionuclide scans, and forearm vascular resistance was determined using venous occlusion plethysmography. In healthy young and old subjects, splanchnic blood volume increased, but supine blood pressure remained unchanged after the meal. In both groups, HR increased and systemic vascular resistance remained stable. Forearm vascular resistance and cardiac index increased after the meal in elderly subjects, whereas these responses were highly variable and of smaller magnitude in the young. Young subjects demonstrated postprandial increases in low-frequency HR spectral power, representing cardiac sympatho-excitation, but plasma NE remained unchanged. In elderly subjects, plasma NE increased after the meal but without changes in the HR power spectrum. Patients with dysautonomia had a large postprandial decline in blood pressure associated with no change in forearm vascular resistance, a fall in systemic vascular resistance, and reduction in left ventricular end diastolic volume index. HR increased in these patients but without changes in plasma NE or the HR power spectrum. CONCLUSIONS. 1) In healthy elderly subjects, the maintenance of blood pressure homeostasis after food ingestion is associated with an increase in HR, forearm vascular resistance, cardiac index, and plasma NE. In both young and old, systemic vascular resistance is

Effects of work stress and home stress on autonomic nervous function in Japanese male workers.

Science.gov (United States)

Maeda, Eri; Iwata, Toyoto; Murata, Katsuyuki

2015-01-01

Autonomic imbalance is one of the important pathways through which psychological stress contributes to cardiovascular diseases/sudden death. Although previous studies have focused mainly on stress at work (work stress), the association between autonomic function and stress at home (home stress) is still poorly understood. The purpose was to clarify the effect of work/home stress on autonomic function in 1,809 Japanese male workers. We measured corrected QT (QTc) interval and QT index on the electrocardiogram along with blood pressure and heart rate. Participants provided self-reported information about the presence/absence of work/home stress and the possible confounders affecting QT indicators. Home stress was related positively to QT index (p=0.040) after adjusting for the possible confounders, though work stress did not show a significant relation to QTc interval or QT index. The odds ratio of home stress to elevated QT index (≥105) was 2.677 (95% CI, 1.050 to 6.822). Work/home stress showed no significant relation to blood pressure or heart rate. These findings suggest that autonomic imbalance, readily assessed by QT indicators, can be induced by home stress in Japanese workers. Additional research is needed to identify different types of home stress that are strongly associated with autonomic imbalance.

Stimulating endogenous cardiac regeneration

Directory of Open Access Journals (Sweden)

Amanda eFinan

2015-09-01

Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

Neurotransmission to parasympathetic cardiac vagal neurons in the brain stem is altered with left ventricular hypertrophy-induced heart failure.

Science.gov (United States)

Cauley, Edmund; Wang, Xin; Dyavanapalli, Jhansi; Sun, Ke; Garrott, Kara; Kuzmiak-Glancy, Sarah; Kay, Matthew W; Mendelowitz, David

2015-10-01

Hypertension, cardiac hypertrophy, and heart failure (HF) are widespread and debilitating cardiovascular diseases that affect nearly 23 million people worldwide. A distinctive hallmark of these cardiovascular diseases is autonomic imbalance, with increased sympathetic activity and decreased parasympathetic vagal tone. Recent device-based approaches, such as implantable vagal stimulators that stimulate a multitude of visceral sensory and motor fibers in the vagus nerve, are being evaluated as new therapeutic approaches for these and other diseases. However, little is known about how parasympathetic activity to the heart is altered with these diseases, and this lack of knowledge is an obstacle in the goal of devising selective interventions that can target and selectively restore parasympathetic activity to the heart. To identify the changes that occur within the brain stem to diminish the parasympathetic cardiac activity, left ventricular hypertrophy was elicited in rats by aortic pressure overload using a transaortic constriction approach. Cardiac vagal neurons (CVNs) in the brain stem that generate parasympathetic activity to the heart were identified with a retrograde tracer and studied using patch-clamp electrophysiological recordings in vitro. Animals with left cardiac hypertrophy had diminished excitation of CVNs, which was mediated both by an augmented frequency of spontaneous inhibitory GABAergic neurotransmission (with no alteration of inhibitory glycinergic activity) as well as a diminished amplitude and frequency of excitatory neurotransmission to CVNs. Opportunities to alter these network pathways and neurotransmitter receptors provide future targets of intervention in the goal to restore parasympathetic activity and autonomic balance to the heart in cardiac hypertrophy and other cardiovascular diseases. Copyright © 2015 the American Physiological Society.

Hypoventilation improvement in an adult non-invasively ventilated patient with Rapid-onset Obesity with Hypothalamic Dysfunction Hypoventilation and Autonomic Dysregulation (ROHHAD).

Science.gov (United States)

Graziani, Alessandro; Casalini, Pierpaolo; Mirici-Cappa, Federica; Pezzi, Giuseppe; Giuseppe Stefanini, Francesco

2016-01-01

Rapid-onset Obesity with Hypothalamic Dysfunction, Hypoventilation, and Autonomic Dysregulation (ROHHAD) is a rare disease of unknown etiology, characterized by rapid-onset obesity in young children, hypoventilation, hypothalamic and autonomic dysfunction. Patients between the ages of 2 and 4 present with hyperphagia and weight gain, followed by neuro-hormonal dysfunction and central hypoventilation months or years later. Cardiac arrest may represent the fatal complication of alveolar hypoventilation and early mechanical ventilation is essential for the patient's life. In this paper, we describe a 22-year-old patient with ROHHAD syndrome who had an acute respiratory failure during nocturnal non-invasive ventilation (NIV).

Higher exercise intensity delays postexercise recovery of impedance-derived cardiac sympathetic activity.

Science.gov (United States)

Michael, Scott; Jay, Ollie; Graham, Kenneth S; Davis, Glen M

2017-08-01

Systolic time intervals (STIs) provide noninvasive insights into cardiac sympathetic neural activity (cSNA). As the effect of exercise intensity on postexercise STI recovery is unclear, this study investigated the STI recovery profile after different exercise intensities. Eleven healthy males cycled for 8 min at 3 separate intensities: LOW (40%-45%), MOD (75%-80%), and HIGH (90%-95%) of heart-rate (HR) reserve. Bio-impedance cardiography was used to assess STIs - primarily pre-ejection period (PEP; inversely correlated with cSNA), as well as left ventricular ejection time (LVET) and PEP:LVET - during 10 min seated recovery immediately postexercise. Heart-rate variability (HRV), i.e., natural-logarithm of root mean square of successive differences (Ln-RMSSD), was calculated as an index of cardiac parasympathetic neural activity (cPNA). Higher preceding exercise intensity elicited a slower recovery of HR and Ln-RMSSD (p return to baseline by 10 min following any intensity (p ≤ 0.009). Recovery of STIs was also slower following higher intensity exercise (p ≤ 0.002). By 30 s postexercise, higher preceding intensity resulted in a lower PEP (98 ± 14 ms, 75 ± 6 ms, 66 ± 5 ms for LOW, MOD, and HIGH, respectively, p fashion. While exercise intensity must be considered, acute recovery may be a valuable period during which to concurrently monitor these noninvasive indices, to identify potentially abnormal cardiac autonomic responses.

Cardiac Coherence, Self-Regulation, Autonomic Stability and Psychosocial Well-being

Directory of Open Access Journals (Sweden)

Rollin eMcCraty

2014-09-01

Full Text Available The ability to alter one’s emotional responses is central to overall well-being and to effectively meeting the demands of life. One of the chief symptoms of events such as trauma, that overwhelm our capacities to successfully handle and adapt to them, is a shift in our internal baseline reference such that there ensues a repetitive activation of the traumatic event. This can result in high vigilance and over-sensitivity to environmental signals which are reflected in inappropriate emotional responses and autonomic nervous system dynamics. In this article we discuss the perspective that one’s ability to self-regulate the quality of feeling and emotion of one’s moment-to-moment experience is intimately tied to our physiology, and the reciprocal interactions among physiological, cognitive and emotional systems. These interactions form the basis of information processing networks in which communication between systems occurs through the generation and transmission of rhythms and patterns of activity. Our discussion emphasizes the communication pathways between the heart and brain, as well as how these are related to cognitive and emotional function and self-regulatory capacity. We discuss the hypothesis that self-induced positive emotions increase the coherence in bodily processes, which is reflected in the pattern of the heart’s rhythm. This shift in the heart rhythm in turn plays an important role in facilitating higher cognitive functions, creating emotional stability and facilitating states of calm. Over time, this establishes a new inner-baseline reference, a type of implicit memory that organizes perception, feelings and behavior. Without establishing a new baseline reference, people are at risk of getting stuck in familiar, yet unhealthy emotional and behavioral patterns and living their lives through the automatic filters of past familiar or traumatic experience.

Comprehensive cardiac rehabilitation

DEFF Research Database (Denmark)

Kruse, Marie; Hochstrasser, Stefan; Zwisler, Ann-Dorthe O

2006-01-01

OBJECTIVES: The costs of comprehensive cardiac rehabilitation are established and compared to the corresponding costs of usual care. The effect on health-related quality of life is analyzed. METHODS: An unprecedented and very detailed cost assessment was carried out, as no guidelines existed...... and may be as high as euro 1.877. CONCLUSIONS: Comprehensive cardiac rehabilitation is more costly than usual care, and the higher costs are not outweighed by a quality of life gain. Comprehensive cardiac rehabilitation is, therefore, not cost-effective....

The effect of Tranexamic acid on cardiac surgery bleeding

Directory of Open Access Journals (Sweden)

Mohammad Esmaeelzadeh

2014-02-01

Full Text Available Serious bleeding in cardiac surgery leads to re-exploration, blood transfusion and increases the risks of mortality and morbidity. Using the lysine analogous of antifibrionlytic agents are the preferred strategy to suppress the need for transfusion procedures and blood products. Although tranexamic acid has been very influential in reducing the transfusion requirement after operation, tranexamic acid induced seizures is one of the common side effects of this drug. Due to inhibiting the fibrinolysis, thrombotic events are other possible side effects of using tranexamic acid. There are no certain results regarding decreasing the mortality rate by using the drug but it is identified that tranexamic acid does not increase the mortality. In this article, we aimed to review the literature on using tranexamic acid in cardiac surgeries.

Purinergic modulation of adult guinea pig cardiomyocytes in long term cultures and co-cultures with extracardiac or intrinsic cardiac neurones.

Science.gov (United States)

Horackova, M; Huang, M H; Armour, J A

1994-05-01

To determine the capacity of ATP to modify cardiomyocytes directly or indirectly via peripheral autonomic neurones, the effects of various purinergic agents were studied on long term cultures of adult guinea pig ventricular myocytes and their co-cultures with extracardiac (stellate ganglion) or intrinsic cardiac neurones. Ventricular myocytes and cardiac neurones were enzymatically dissociated and plated together or alone (myocytes only). Myocyte cultures were used for experiments after three to six weeks. The electrical and contractile properties of cultured myocytes and myocyte-neuronal networks were investigated. The spontaneous beating frequency of ventricular myocytes co-cultured with stellate ganglion neurones increased by approximately 140% (p under control conditions, but when beta adrenergic receptors of tetrodotoxin sensitive neural responses were blocked, ATP induced greater augmentation (> 100%). In contrast, ATP induced much smaller effects in non-innervated myocyte cultures (approximately 26%, p UTP > MSATP > beta gamma ATP > alpha beta ATP. Adenosine (10(-4) M) attenuated the beating frequency of myocytes in both types of co-culture, while not significantly affecting non-innervated myocyte cultures. The experimental model used in this study showed that extrinsic and intrinsic cardiac neurones which possess P2 receptors can greatly enhance cardiac myocyte contractile rate when activated by ATP. Since adenosine reduced contractile rate in both types of co-cultures while not affecting non-innervated myocytes, it is concluded that some of these neurones possess P1 receptors.

Cardiac arrest during gamete release in chum salmon regulated by the parasympathetic nerve system.

Directory of Open Access Journals (Sweden)

Yuya Makiguchi

Full Text Available Cardiac arrest caused by startling stimuli, such as visual and vibration stimuli, has been reported in some animals and could be considered as an extraordinary case of bradycardia and defined as reversible missed heart beats. Variability of the heart rate is established as a balance between an autonomic system, namely cholinergic vagus inhibition, and excitatory adrenergic stimulation of neural and hormonal action in teleost. However, the cardiac arrest and its regulating nervous mechanism remain poorly understood. We show, by using electrocardiogram (ECG data loggers, that cardiac arrest occurs in chum salmon (Oncorhynchus keta at the moment of gamete release for 7.39+/-1.61 s in females and for 5.20+/-0.97 s in males. The increase in heart rate during spawning behavior relative to the background rate during the resting period suggests that cardiac arrest is a characteristic physiological phenomenon of the extraordinarily high heart rate during spawning behavior. The ECG morphological analysis showed a peaked and tall T-wave adjacent to the cardiac arrest, indicating an increase in potassium permeability in cardiac muscle cells, which would function to retard the cardiac action potential. Pharmacological studies showed that the cardiac arrest was abolished by injection of atropine, a muscarinic receptor antagonist, revealing that the cardiac arrest is a reflex response of the parasympathetic nerve system, although injection of sotalol, a beta-adrenergic antagonist, did not affect the cardiac arrest. We conclude that cardiac arrest during gamete release in spawning release in spawning chum salmon is a physiological reflex response controlled by the parasympathetic nervous system. This cardiac arrest represents a response to the gaping behavior that occurs at the moment of gamete release.

Inflammatory and apoptotic remodeling in autonomic nervous system following myocardial infarction.

Directory of Open Access Journals (Sweden)

Chen Gao

Full Text Available Chronic myocardial infarction (MI triggers pathological remodeling in the heart and cardiac nervous system. Abnormal function of the autonomic nervous system (ANS, including stellate ganglia (SG and dorsal root ganglia (DRG contribute to increased sympathoexcitation, cardiac dysfunction and arrythmogenesis. ANS modulation is a therapeutic target for arrhythmia associated with cardiac injury. However, the molecular mechanism involved in the pathological remodeling in ANS following cardiac injury remains to be established.In this study, we performed transcriptome analysis by RNA-sequencing in thoracic SG and (T1-T4 DRG obtained from Yorkshire pigs following either acute (3 to 5 hours or chronic (8 weeks myocardial infarction. By differential expression and weighted gene co-expression network analysis (WGCNA, we identified significant transcriptome changes and specific gene modules in the ANS tissues in response to myocardial infarction at either acute or chronic phases. Both differential expressed genes and the member genes of the WGCNA gene module associated with post-infarct condition were significantly enriched for inflammatory signaling and apoptotic cell death. Targeted validation analysis supported a significant induction of inflammatory and apoptotic signal in both SG and DRG following myocardial infarction, along with cellular evidence of apoptosis induction based on TUNEL analysis. Importantly, these molecular changes were observed specifically in the thoracic segments but not in their counterparts obtained from lumbar sections.Myocardial injury leads to time-dependent global changes in gene expression in the innervating ANS. Induction of inflammatory gene expression and loss of neuron cell viability in SG and DRG are potential novel mechanisms contributing to abnormal ANS function which can promote cardiac arrhythmia and pathological remodeling in myocardium.

Cardiac gated ventilation

International Nuclear Information System (INIS)

Hanson, C.W. III; Hoffman, E.A.

1995-01-01

There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. The authors evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50 msec scan aperture. Multi slice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. The authors observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a non-failing model of the heart

The Effect of Chinese ESL Learners’ Beliefs on their Autonomous Learning

Directory of Open Access Journals (Sweden)

Qunyan Zhong

2010-12-01

Full Text Available What beliefs do Chinese learners hold about language learning? What is the effect of these beliefs on their autonomous learning? These are the two questions that this study aims to address. I employed naturalistic inquiry (Lincoln & Guba, 1985 to investigate five Chinese ESL learners’ beliefs about language learning and their learning behaviour. A number of instruments (interviews, classroom observations and stimulated recall, learning logs were used to collect triangulated data over a 12-week period. Following standard procedures of qualitative data analysis, I identified five categories of learners’ beliefs. The results revealed that the beliefs that the learners held were context-specific, reflecting their learning experiences. Some of them were conducive to learning autonomy while others were not. The beliefs influenced the level of the learners’ autonomy. The study suggests that educators should take into account learners’ beliefs when promoting autonomous learning.

Genetic autonomic disorders.

Science.gov (United States)

Axelrod, Felicia B

2013-03-01

Genetic disorders affecting the autonomic nervous system can result in abnormal development of the nervous system or they can be caused by neurotransmitter imbalance, an ion-channel disturbance or by storage of deleterious material. The symptoms indicating autonomic dysfunction, however, will depend upon whether the genetic lesion has disrupted peripheral or central autonomic centers or both. Because the autonomic nervous system is pervasive and affects every organ system in the body, autonomic dysfunction will result in impaired homeostasis and symptoms will vary. The possibility of genetic confirmation by molecular testing for specific diagnosis is increasing but treatments tend to remain only supportive and directed toward particular symptoms. Copyright © 2013 Elsevier Inc. All rights reserved.

Nurse practitioners in postoperative cardiac surgery: are they effective?

Science.gov (United States)

Goldie, Catherine L; Prodan-Bhalla, Natasha; Mackay, Martha

2012-01-01

High demand for acute care nurse practitioners (ACNPs) in Canadian postoperative cardiac surgery settings has outpaced methodologically rigorous research to support the role. To compare the effectiveness of ACNP-led care to hospitalist-led care in a postoperative cardiac surgery unit in a Canadian, university-affiliated, tertiary care hospital. Patients scheduled for urgent or elective coronary artery bypass and/or valvular surgery were randomly assigned to either ACNP-led (n=22) or hospitalist-led (n=81) postoperative care. Both ACNPs and hospitalists worked in collaboration with a cardiac surgeon. Outcome variables included length of hospital stay, hospital readmission rate, postoperative complications, adherence to follow-up appointments, attendance at cardiac rehabilitation and both patient and health care team satisfaction. Baseline demographic characteristics were similar between groups except more patients in the ACNP-led group had had surgery on an urgent basis (p < or = 0.01), and had undergone more complicated surgical procedures (p < or =0.01). After discharge, more patients in the hospitalist-led group had visited their family doctor within a week (p < or =0.02) and measures of satisfaction relating to teaching, answering questions, listening and pain management were higher in the ACNP-led group. Although challenges in recruitment yielded a lower than anticipated sample size, this study contributes to our knowledge of the ACNP role in postoperative cardiac surgery. Our findings provide support for the ACNP role in this setting as patients who received care from an ACNP had similar outcomes to hospitalist-led care and reported greater satisfaction in some measures of care.

Physics Simulation Software for Autonomous Propellant Loading and Gas House Autonomous System Monitoring

Science.gov (United States)

Regalado Reyes, Bjorn Constant

2015-01-01

1. Kennedy Space Center (KSC) is developing a mobile launching system with autonomous propellant loading capabilities for liquid-fueled rockets. An autonomous system will be responsible for monitoring and controlling the storage, loading and transferring of cryogenic propellants. The Physics Simulation Software will reproduce the sensor data seen during the delivery of cryogenic fluids including valve positions, pressures, temperatures and flow rates. The simulator will provide insight into the functionality of the propellant systems and demonstrate the effects of potential faults. This will provide verification of the communications protocols and the autonomous system control. 2. The High Pressure Gas Facility (HPGF) stores and distributes hydrogen, nitrogen, helium and high pressure air. The hydrogen and nitrogen are stored in cryogenic liquid state. The cryogenic fluids pose several hazards to operators and the storage and transfer equipment. Constant monitoring of pressures, temperatures and flow rates are required in order to maintain the safety of personnel and equipment during the handling and storage of these commodities. The Gas House Autonomous System Monitoring software will be responsible for constantly observing and recording sensor data, identifying and predicting faults and relaying hazard and operational information to the operators.

Adrenergic Blockade Bi-directionally and Asymmetrically Alters Functional Brain-Heart Communication and Prolongs Electrical Activities of the Brain and Heart during Asphyxic Cardiac Arrest

Science.gov (United States)

Tian, Fangyun; Liu, Tiecheng; Xu, Gang; Li, Duan; Ghazi, Talha; Shick, Trevor; Sajjad, Azeem; Wang, Michael M.; Farrehi, Peter; Borjigin, Jimo

2018-01-01

Sudden cardiac arrest is a leading cause of death in the United States. The neurophysiological mechanism underlying sudden death is not well understood. Previously we have shown that the brain is highly stimulated in dying animals and that asphyxia-induced death could be delayed by blocking the intact brain-heart neuronal connection. These studies suggest that the autonomic nervous system plays an important role in mediating sudden cardiac arrest. In this study, we tested the effectiveness of phentolamine and atenolol, individually or combined, in prolonging functionality of the vital organs in CO2-mediated asphyxic cardiac arrest model. Rats received either saline, phentolamine, atenolol, or phentolamine plus atenolol, 30 min before the onset of asphyxia. Electrocardiogram (ECG) and electroencephalogram (EEG) signals were simultaneously collected from each rat during the entire process and investigated for cardiac and brain functions using a battery of analytic tools. We found that adrenergic blockade significantly suppressed the initial decline of cardiac output, prolonged electrical activities of both brain and heart, asymmetrically altered functional connectivity within the brain, and altered, bi-directionally and asymmetrically, functional, and effective connectivity between the brain and heart. The protective effects of adrenergic blockers paralleled the suppression of brain and heart connectivity, especially in the right hemisphere associated with central regulation of sympathetic function. Collectively, our results demonstrate that blockade of brain-heart connection via alpha- and beta-adrenergic blockers significantly prolonged the detectable activities of both the heart and the brain in asphyxic rat. The beneficial effects of combined alpha and beta blockers may help extend the survival of cardiac arrest patients. PMID:29487541

Adrenergic Blockade Bi-directionally and Asymmetrically Alters Functional Brain-Heart Communication and Prolongs Electrical Activities of the Brain and Heart during Asphyxic Cardiac Arrest

Directory of Open Access Journals (Sweden)

Fangyun Tian

2018-02-01

Full Text Available Sudden cardiac arrest is a leading cause of death in the United States. The neurophysiological mechanism underlying sudden death is not well understood. Previously we have shown that the brain is highly stimulated in dying animals and that asphyxia-induced death could be delayed by blocking the intact brain-heart neuronal connection. These studies suggest that the autonomic nervous system plays an important role in mediating sudden cardiac arrest. In this study, we tested the effectiveness of phentolamine and atenolol, individually or combined, in prolonging functionality of the vital organs in CO2-mediated asphyxic cardiac arrest model. Rats received either saline, phentolamine, atenolol, or phentolamine plus atenolol, 30 min before the onset of asphyxia. Electrocardiogram (ECG and electroencephalogram (EEG signals were simultaneously collected from each rat during the entire process and investigated for cardiac and brain functions using a battery of analytic tools. We found that adrenergic blockade significantly suppressed the initial decline of cardiac output, prolonged electrical activities of both brain and heart, asymmetrically altered functional connectivity within the brain, and altered, bi-directionally and asymmetrically, functional, and effective connectivity between the brain and heart. The protective effects of adrenergic blockers paralleled the suppression of brain and heart connectivity, especially in the right hemisphere associated with central regulation of sympathetic function. Collectively, our results demonstrate that blockade of brain-heart connection via alpha- and beta-adrenergic blockers significantly prolonged the detectable activities of both the heart and the brain in asphyxic rat. The beneficial effects of combined alpha and beta blockers may help extend the survival of cardiac arrest patients.

Patients With Fibromyalgia Have Significant Autonomic Symptoms But Modest Autonomic Dysfunction.

Science.gov (United States)

Vincent, Ann; Whipple, Mary O; Low, Phillip A; Joyner, Michael; Hoskin, Tanya L

2016-05-01

Research suggests that disordered autonomic function may be one contributor to deconditioning reported in fibromyalgia; however, no study to date has assessed these variables simultaneously with comprehensive measures. To characterize physical fitness and autonomic function with the use of clinically validated measures and subjective questionnaires between patients with fibromyalgia and healthy controls. Cross-sectional, observational, controlled study. Community sample of patients with fibromyalgia and healthy controls. Thirty patients with fibromyalgia and 30 pain and fatigue-free controls. Participants completed a battery of self-report questionnaires and physiological measures, including clinically validated measures of physical fitness and autonomic function. Six-Minute Walk Test total distance, maximal oxygen consumption as assessed by cardiopulmonary exercise testing, total steps using activity monitor, Composite Autonomic Scoring Scale as assessed by Autonomic Reflex Screen, total metabolic equivalents per week using the International Physical Activity Questionnaire, and self-reported autonomic symptoms via the 31-item Composite Autonomic Symptom Score questionnaire. Autonomic function, as assessed by self-report, was significantly different between patients and controls (P physical activity was not significantly different between patients and controls (P = .99), but levels of moderate and vigorous physical activity as measured by actigraphy were significantly lower in patients (P = .012 and P = .047, respectively). Exercise capacity (6-Minute Walk) was poorer in patients (P = .0006), but there was no significant difference in maximal volume of oxygen consumption (P = .07). Patients with fibromyalgia report more severe symptoms across all domains, including physical activity and autonomic symptoms, compared with controls, but the objective assessments only showed modest differences. Our results suggest that patients with widespread subjective impairment of

Dissociation of sad facial expressions and autonomic nervous system responding in boys with disruptive behavior disorders

Science.gov (United States)

Marsh, Penny; Beauchaine, Theodore P.; Williams, Bailey

2009-01-01

Although deficiencies in emotional responding have been linked to externalizing behaviors in children, little is known about how discrete response systems (e.g., expressive, physiological) are coordinated during emotional challenge among these youth. We examined time-linked correspondence of sad facial expressions and autonomic reactivity during an empathy-eliciting task among boys with disruptive behavior disorders (n = 31) and controls (n = 23). For controls, sad facial expressions were associated with reduced sympathetic (lower skin conductance level, lengthened cardiac preejection period [PEP]) and increased parasympathetic (higher respiratory sinus arrhythmia [RSA]) activity. In contrast, no correspondence between facial expressions and autonomic reactivity was observed among boys with conduct problems. Furthermore, low correspondence between facial expressions and PEP predicted externalizing symptom severity, whereas low correspondence between facial expressions and RSA predicted internalizing symptom severity. PMID:17868261

Modeling the autonomic and metabolic effects of obstructive sleep apnea: A simulation study.

Directory of Open Access Journals (Sweden)

Limei eCheng

2012-01-01

Full Text Available Long term exposure to intermittent hypoxia and sleep fragmentation introduced by recurring obstructive sleep apnea has been linked to subsequent cardiovascular disease and Type 2 diabetes. The underlying mechanisms remain unclear, but impairment of the normal interactions among the systems that regulate autonomic and metabolic function is likely involved. We have extended an existing integrative model of respiratory, cardiovascular and sleep-wake state control, to incorporate a sub-model of glucose-insulin-fatty acid regulation. This computational model is capable of simulating the complex dynamics of cardiorespiratory control, chemoreflex and state-related control of breath-to-breath ventilation, state-related and chemoreflex control of upper airway potency, respiratory and circulatory mechanics, as well as the metabolic control of glucose insulin dynamics and its interactions with the autonomic control. The interactions between autonomic and metabolic control include the circadian regulation of epinephrine secretion, epinephrine regulation on dynamic fluctuations in glucose and free-fatty acid in plasma, metabolic coupling among tissues and organs provided by insulin and epinephrine, as well as the effect of insulin on peripheral vascular sympathetic activity. These model simulations provide insight into the relative importance of the various mechanisms that determine the acute and chronic physiological effects of sleep-disordered breathing. The model can also be used to investigate the effects of a variety of interventions, such as different glucose clamps, the intravenous glucose tolerance test and the application of continuous positive airway pressure on obstructive sleep apnea subjects. As such, this model provides the foundation on which future efforts to simulate disease progression and the long-term effects of pharmacological intervention can be based.

Experimental observations of EMI effects in autonomous Chua's chaotic circuit

International Nuclear Information System (INIS)

Kilic, Recai; Saracoglu, O. Galip; Yildirim, Fatma

2007-01-01

This paper deals with the experimentally investigation of EMI effects in autonomous Chua's chaotic circuit. We realized this experimental investigation by constructing an experimental setup subject to a Chua's circuit and applying a 5-30 MHz/100-200 mV EMI signal to the input pins of voltage Op-Amps used for realizing nonlinear resistor in Chua's circuit. In addition, we also experimentally investigated whether EMI signals affect the chaos synchronization between two Chua's chaotic circuits or not

Premature Ventricular Contraction Coupling Interval Variability Destabilizes Cardiac Neuronal and Electrophysiological Control: Insights from Simultaneous Cardio-Neural Mapping

Science.gov (United States)

Hamon, David; Rajendran, Pradeep S.; Chui, Ray W.; Ajijola, Olujimi A.; Irie, Tadanobu; Talebi, Ramin; Salavatian, Siamak; Vaseghi, Marmar; Bradfield, Jason S.; Armour, J. Andrew; Ardell, Jeffrey L.; Shivkumar, Kalyanam

2017-01-01

Background Variability in premature ventricular contraction (PVC) coupling interval (CI) increases the risk of cardiomyopathy and sudden death. The autonomic nervous system regulates cardiac electrical and mechanical indices, and its dysregulation plays an important role in cardiac disease pathogenesis. The impact of PVCs on the intrinsic cardiac nervous system (ICNS), a neural network on the heart, remains unknown. The objective was to determine the effect of PVCs and CI on ICNS function in generating cardiac neuronal and electrical instability using a novel cardio-neural mapping approach. Methods and Results In a porcine model (n=8) neuronal activity was recorded from a ventricular ganglion using a microelectrode array, and cardiac electrophysiological mapping was performed. Neurons were functionally classified based on their response to afferent and efferent cardiovascular stimuli, with neurons that responded to both defined as convergent (local reflex processors). Dynamic changes in neuronal activity were then evaluated in response to right ventricular outflow tract PVCs with fixed short, fixed long, and variable CI. PVC delivery elicited a greater neuronal response than all other stimuli (P<0.001). Compared to fixed short and long CI, PVCs with variable CI had a greater impact on neuronal response (P<0.05 versus short CI), particularly on convergent neurons (P<0.05), as well as neurons receiving sympathetic (P<0.05) and parasympathetic input (P<0.05). The greatest cardiac electrical instability was also observed following variable (short) CI PVCs. Conclusions Variable CI PVCs affect critical populations of ICNS neurons and alter cardiac repolarization. These changes may be critical for arrhythmogenesis and remodeling leading to cardiomyopathy. PMID:28408652

Cardiac Autonomic Modulations and Psychological Correlates in the Yukon Arctic Ultra: The Longest and the Coldest Ultramarathon

Directory of Open Access Journals (Sweden)

Lea C. Rundfeldt

2018-02-01

Full Text Available Studies on human physical performance in extreme environments have effectively approached the investigation of adaptation mechanisms and their physiological limits. As scientific interest in the interplay between physiological and psychological aspects of performance is growing, we aimed to investigate cardiac autonomic control, by means of heart rate variability, and psychological correlates, in competitors of a subarctic ultramarathon, taking place over a 690 km course (temperatures between +5 and −47°C. At baseline (PRE, after 277 km (D1, 383 km (D2, and post-race (POST, 690 km, heart rate (HR recordings (supine, 15 min, psychometric measurements (Profile of Mood States/POMS, Borg fatigue, and Karolinska Sleepiness Scale scores both upon arrival and departure were obtained in 16 competitors (12 men, 4 women, 38.6 ± 9.5 years. As not all participants reached the finish line, comparison of finishers (FIN, n = 10 and non-finishers (NON, n = 6, allowed differential assessment of performance. Resting HR increased overall significantly at D1 (FIN +15.9; NON +14.0 bpm, due to a significant decrease in parasympathetic drive. This decrease was in FIN only partially recovered toward POST. In FIN only, baseline HR was negatively correlated with mean velocity [r −0.63 (P.04] and parasympathetic drive [pNN50+: r −0.67 (P.03], a lower HR and a higher vagal tone predicting a better performance. Moreover, in FIN, a persistent increase of the long-term self-similarity coefficient, assessed by detrended fluctuation analysis (DFAα2, was retrieved, possibly due to higher alertness. As for psychometrics, at D1, POMS Vigor decreased (FIN: −7.0; NON: −3.8, while Fatigue augmented (FIN: +6.9; NON: +5.0. Sleepiness increased only in NON, while Borg scales did not exhibit changes. Baseline comparison of mood states with normative data for athletes displayed significantly higher positive mood in our athletes. Results show that: the race conditions induced

Cardiac Autonomic Neuropathy May Play a Role in Pathogenesis of Atherosclerosis in Type 1 Diabetes Mellitus

Czech Academy of Sciences Publication Activity Database

Malá, Š.; Potočková, V.; Hoskovcová, L.; Pithová, P.; Brabec, Marek; Kulhánková, J.; Keil, R.; Riedlbauchová, L.; Brož, J.

2017-01-01

Roč. 134, December (2017), s. 139-144 ISSN 0168-8227 Institutional support: RVO:67985807 Keywords : autonomic neuropathy * diabetes mellitus * intima media thickness * atherosclerosis * heart rate variability Subject RIV: BB - Applied Statistics, Operational Research OBOR OECD: Statistics and probability Impact factor: 3.639, year: 2016

Effects of catheter-based renal denervation on cardiac sympathetic activity and innervation in patients with resistant hypertension.

Science.gov (United States)

Donazzan, Luca; Mahfoud, Felix; Ewen, Sebastian; Ukena, Christian; Cremers, Bodo; Kirsch, Carl-Martin; Hellwig, Dirk; Eweiwi, Tareq; Ezziddin, Samer; Esler, Murray; Böhm, Michael

2016-04-01

To investigate, whether renal denervation (RDN) has a direct effect on cardiac sympathetic activity and innervation density. RDN demonstrated its efficacy not only in reducing blood pressure (BP) in certain patients, but also in decreasing cardiac hypertrophy and arrhythmias. These pleiotropic effects occur partly independent from the observed BP reduction. Eleven patients with resistant hypertension (mean office systolic BP 180 ± 18 mmHg, mean antihypertensive medications 6.0 ± 1.5) underwent I-123-mIBG scintigraphy to exclude pheochromocytoma. We measured cardiac sympathetic innervation and activity before and 9 months after RDN. Cardiac sympathetic innervation was assessed by heart to mediastinum ratio (H/M) and sympathetic activity by wash out ratio (WOR). Effects on office BP, 24 h ambulatory BP monitoring, were documented. Office systolic BP and mean ambulatory systolic BP were significantly reduced from 180 to 141 mmHg (p = 0.006) and from 149 to 129 mmHg (p = 0.014), respectively. Cardiac innervation remained unchanged before and after RDN (H/M 2.5 ± 0.5 versus 2.6 ± 0.4, p = 0.285). Cardiac sympathetic activity was significantly reduced by 67 % (WOR decreased from 24.1 ± 12.7 to 7.9 ± 25.3 %, p = 0.047). Both, responders and non-responders experienced a reduction of cardiac sympathetic activity. RDN significantly reduced cardiac sympathetic activity thereby demonstrating a direct effect on the heart. These changes occurred independently from BP effects and provide a pathophysiological basis for studies, investigating the potential effect of RDN on arrhythmias and heart failure.

Regulation of cardiac remodeling by cardiac Na/K-ATPase isoforms

Directory of Open Access Journals (Sweden)

Lijun Catherine Liu

2016-09-01

Full Text Available Cardiac remodeling occurs after cardiac pressure/volume overload or myocardial injury during the development of heart failure and is a determinant of heart failure. Preventing or reversing remodeling is a goal of heart failure therapy. Human cardiomyocyte Na+/K+-ATPase has multiple α isoforms (1-3. The expression of the α subunit of the Na+/K+-ATPase is often altered in hypertrophic and failing hearts. The mechanisms are unclear. There are limited data from human cardiomyocytes. Abundant evidences from rodents show that Na+/K+-ATPase regulates cardiac contractility, cell signaling, hypertrophy and fibrosis. The α1 isoform of the Na+/K+-ATPase is the ubiquitous isoform and possesses both pumping and signaling functions. The α2 isoform of the Na+/K+-ATPase regulates intracellular Ca2+ signaling, contractility and pathological hypertrophy. The α3 isoform of the Na+/K+-ATPase may also be a target for cardiac hypertrophy. Restoration of cardiac Na+/K+-ATPase expression may be an effective approach for prevention of cardiac remodeling. In this article, we will overview: (1 the distribution and function of isoform specific Na+/K+-ATPase in the cardiomyocytes. (2 the role of cardiac Na+/K+-ATPase in the regulation of cell signaling, contractility, cardiac hypertrophy and fibrosis in vitro and in vivo. Selective targeting of cardiac Na+/K+-ATPase isoform may offer a new target for the prevention of cardiac remodeling.

Sitagliptin reduces cardiac apoptosis, hypertrophy and fibrosis primarily by insulin-dependent mechanisms in experimental type-II diabetes. Potential roles of GLP-1 isoforms.

Directory of Open Access Journals (Sweden)

Belén Picatoste

Full Text Available BACKGROUND: Myocardial fibrosis is a key process in diabetic cardiomyopathy. However, their underlying mechanisms have not been elucidated, leading to a lack of therapy. The glucagon-like peptide-1 (GLP-1 enhancer, sitagliptin, reduces hyperglycemia but may also trigger direct effects on the heart. METHODS: Goto-Kakizaki (GK rats developed type-II diabetes and received sitagliptin, an anti-hyperglycemic drug (metformin or vehicle (n=10, each. After cardiac structure and function assessment, plasma and left ventricles were isolated for biochemical studies. Cultured cardiomyocytes and fibroblasts were used for in vitro assays. RESULTS: Untreated GK rats exhibited hyperglycemia, hyperlipidemia, plasma GLP-1 decrease, and cardiac cell-death, hypertrophy, fibrosis and prolonged deceleration time. Moreover, cardiac pro-apoptotic/necrotic, hypertrophic and fibrotic factors were up-regulated. Importantly, both sitagliptin and metformin lessened all these parameters. In cultured cardiomyocytes and cardiac fibroblasts, high-concentration of palmitate or glucose induced cell-death, hypertrophy and fibrosis. Interestingly, GLP-1 and its insulinotropic-inactive metabolite, GLP-1(9-36, alleviated these responses. In addition, despite a specific GLP-1 receptor was only detected in cardiomyocytes, GLP-1 isoforms attenuated the pro-fibrotic expression in cardiomyocytes and fibroblasts. In addition, GLP-1 receptor signalling may be linked to PPARδ activation, and metformin may also exhibit anti-apoptotic/necrotic and anti-fibrotic direct effects in cardiac cells. CONCLUSIONS: Sitagliptin, via GLP-1 stabilization, promoted cardioprotection in type-II diabetic hearts primarily by limiting hyperglycemia e hyperlipidemia. However, GLP-1 and GLP-1(9-36 promoted survival and anti-hypertrophic/fibrotic effects on cultured cardiac cells, suggesting cell-autonomous cardioprotective actions.

Resting spontaneous baroreflex sensitivity and cardiac autonomic control in anabolic androgenic steroid users

OpenAIRE

Santos, Marcelo R. dos; Sayegh, Ana L.C.; Armani, Rafael; Costa-Hong, Valéria; Souza, Francis R. de; Toschi-Dias, Edgar; Bortolotto, Luiz A.; Yonamine, Mauricio; Negrão, Carlos E.; Alves, Maria-Janieire N.N.

2018-01-01

OBJECTIVES: Misuse of anabolic androgenic steroids in athletes is a strategy used to enhance strength and skeletal muscle hypertrophy. However, its abuse leads to an imbalance in muscle sympathetic nerve activity, increased vascular resistance, and increased blood pressure. However, the mechanisms underlying these alterations are still unknown. Therefore, we tested whether anabolic androgenic steroids could impair resting baroreflex sensitivity and cardiac sympathovagal control. In addition, ...

In patient's with Parkinson disease, autonomic symptoms are frequent and associated with other non-motor symptoms.

Science.gov (United States)

Arnao, Valentina; Cinturino, Antonio; Valentino, Francesca; Perini, Valentina; Mastrilli, Sergio; Bellavia, Gabriele; Savettieri, Giovanni; Realmuto, Sabrina; D'Amelio, Marco

2015-10-01

Autonomic symptoms and sleep disorders are common non-motor symptoms of Parkinson disease (PD), which are correlated with poor quality of life for patients. To assess the frequency of autonomic symptoms in a consecutive series of PD patients and to correlate them with other motor and non-motor symptoms. All consecutive non-demented PD patients who underwent an extensive evaluation including Hoehn and Yahr staging, Unified Parkinson's Disease Rating Scale, Beck's Depression Inventory, Neuropsychiatric Inventory, PDQ-39 Scale, the Parkinson's diseases Sleep Scale, the Epworth Sleepiness Scale and SCOPA-AUT scale were enrolled. Comorbidity has been also considered. Supine to standing position blood pressure and cardiac frequency changes were also measured. 135 PD patients were included (mean age at interview 67.7; mean disease duration: 5.3 years). Patients were stratified according to mean SCOPA-AUT scale score (13.1). Those with higher SCOPA-AUT scale score were significantly older, had longer disease duration, worse disease stage, worse quality of sleep, were more severely affected, and were also taking a higher dosage of levodopa. At multivariate analysis, older age, longer disease duration, and worse quality of sleep were independently associated with higher SCOPA-AUT scale scores. Our results remark the role of autonomic symptoms in PD. In our patient population, characterized by mild to moderate disease severity, most of the patients complained of autonomic nervous system involvement (84%). A significant association between autonomic symptoms and sleep disorders was also observed.

Effect of 48 h Fasting on Autonomic Function, Brain Activity, Cognition, and Mood in Amateur Weight Lifters

Science.gov (United States)

Skurvydas, Albertas

2016-01-01

Objectives. The acute fasting-induced cardiovascular autonomic response and its effect on cognition and mood remain debatable. Thus, the main purpose of this study was to estimate the effect of a 48 h, zero-calorie diet on autonomic function, brain activity, cognition, and mood in amateur weight lifters. Methods. Nine participants completed a 48 h, zero-calorie diet program. Cardiovascular autonomic function, resting frontal brain activity, cognitive performance, and mood were evaluated before and after fasting. Results. Fasting decreased (p Fasting decreased (p Fasting also increased (p fasting resulted in higher parasympathetic activity and decreased resting frontal brain activity, increased anger, and improved prefrontal-cortex-related cognitive functions, such as mental flexibility and set shifting, in amateur weight lifters. In contrast, hippocampus-related cognitive functions were not affected by it. PMID:28025637

Semi-Autonomous Systems Laboratory

Data.gov (United States)

Federal Laboratory Consortium — VisionThe Semi-Autonomous Systems Lab focuses on developing a comprehensive framework for semi-autonomous coordination of networked robotic systems. Semi-autonomous...

Compact autonomous navigation system (CANS)

Science.gov (United States)

Hao, Y. C.; Ying, L.; Xiong, K.; Cheng, H. Y.; Qiao, G. D.

2017-11-01

Autonomous navigation of Satellite and constellation has series of benefits, such as to reduce operation cost and ground station workload, to avoid the event of crises of war and natural disaster, to increase spacecraft autonomy, and so on. Autonomous navigation satellite is independent of ground station support. Many systems are developed for autonomous navigation of satellite in the past 20 years. Along them American MANS (Microcosm Autonomous Navigation System) [1] of Microcosm Inc. and ERADS [2] [3] (Earth Reference Attitude Determination System) of Honeywell Inc. are well known. The systems anticipate a series of good features of autonomous navigation and aim low cost, integrated structure, low power consumption and compact layout. The ERADS is an integrated small 3-axis attitude sensor system with low cost and small volume. It has the Earth center measurement accuracy higher than the common IR sensor because the detected ultraviolet radiation zone of the atmosphere has a brightness gradient larger than that of the IR zone. But the ERADS is still a complex system because it has to eliminate many problems such as making of the sapphire sphere lens, birefringence effect of sapphire, high precision image transfer optical fiber flattener, ultraviolet intensifier noise, and so on. The marginal sphere FOV of the sphere lens of the ERADS is used to star imaging that may be bring some disadvantages., i.e. , the image energy and attitude measurements accuracy may be reduced due to the tilt image acceptance end of the fiber flattener in the FOV. Besides Japan, Germany and Russia developed visible earth sensor for GEO [4] [5]. Do we have a way to develop a cheaper/easier and more accurate autonomous navigation system that can be used to all LEO spacecraft, especially, to LEO small and micro satellites? To return this problem we provide a new type of the system—CANS (Compact Autonomous Navigation System) [6].

The influence of resistance exercise with emphasis on specific contractions (concentric vs. eccentric on muscle strength and post-exercise autonomic modulation: a randomized clinical trial

Directory of Open Access Journals (Sweden)

Mariana O. Gois

2014-01-01

Full Text Available Background: Compared to eccentric contractions, concentric contractions result in higher cardiovascular stress. However, we do not know how these two types of contractions influence cardiac autonomic modulation during the post-exercise recovery period. Objective: to compare the effect of resistance training that is performed with concentric vs. eccentric emphasis on muscle strength and on post-exercise recovery which was assessed by examining heart rate variability (HRV, for the knee extensor muscle group in young healthy adults. Methods: For this study, 105 men between 18 and 30 years of age were randomized into 4 groups: concentric control (CONCC, eccentric control (ECCC, concentric training (CONCT and eccentric training (ECCT. The CONCC and ECCC groups underwent one session of resistance exercise (RE using the knee extensor muscle group (3 sets of 1 repetition at 100% of the maximal repetition [1MR] and the CONCT and ECCT groups performed 10 training sessions. The HRV was analyzed at baseline and across four recovery periods (T1, T2, T3 and T4. Results: The ECCT group exhibited increased muscle strength at the end of the study. Regarding cardiac autonomic modulation, the CONCC and ECCC groups exhibited increases in overall variability (SDNN and SD2 at T1 compared to baseline, and the ECCT group demonstrated increases in variables reflecting vagal modulation and the recovery process (RMSSD, SD1 and HF [ms2] at T1, T2 and T4 compared to baseline. Conclusions: Resistance training with emphasis on eccentric contractions promoted strength gain and an increase in cardiac vagal modulation during recovery compared to baseline.

Optimal Technique in Cardiac Anesthesia Recovery

OpenAIRE

Svircevic, V.

2014-01-01

The aim of this thesis is to evaluate fast-track cardiac anesthesia techniques and investigate their impact on postoperative mortality, morbidity and quality of life. The following topics will be discussed in the thesis. (1.) Is fast track cardiac anesthesia a safe technique for cardiac surgery? (2.) Does thoracic epidural anesthesia have an effect on mortality and morbidity after cardiac surgery? (3.) Does thoracic epidural anesthesia have an effect on quality of life after cardiac surgery? ...

Predictive value of cardiac autonomic indexes and MIBG washout in ICD recipients with mild to moderate heart failure

International Nuclear Information System (INIS)

Koutelou, M.; Katsikis, A.; Livanis, E.; Georgiadis, M.; Voudris, V.; Flevari, P.; Kremastinos, D.; Theodorakis, G.

2009-01-01

We aimed at evaluating the combined use of heart rate variability (HRV), baroreflex sensitivity (BRS), and metaiodobenzylguanidine (MIBG) imaging in the risk stratification for sudden cardiac death (SCD) of patients with mild to moderate heart failure. Twenty-five patients (17 male and 8 female, mean age 63±5 years, mean left ventricular ejection fraction (LVEF) 36±3%) with a recently implanted cardioverter-defibrillator (ICD) and mild (NYHA I-II) heart failure due to either ischemic (n=15) or dilated (n=10) cardiomyopathy were studied. One week after ICD implantation they underwent baroreflex sensitivity (BRS) evaluation to bolus phenylephrine by the Oxford method, 24-h heart rate variability (HRV) assessment, and MIBG imaging. The mean patient follow-up was 32±10 months. Simple correlation and stepwise multiple regression analysis was performed to evaluate if the number of sustained ventricular tachycardia (cycle length <330 ms) or fibrillation episodes per month is related to one or more of MIBG, BRS, and HRV indexes and if MIBG % washout is related to HRV and/or BRS. The frequency of fast ventricular arrhythmic episodes (FVAE) demonstrated an inverse relation to BRS (p<0.0001), rMSSD (p=0.001), and pNN50 (p=0.0034), while it was positively related to low frequency (LF) (p<0.0001) and MIBG % washout (p=0.001). BRS, LF, rMSSD, and MIBG washout were also independent predictors of FVAE. MIBG washout was related to only one HRV marker (SDNN-I, p<0.0001), while no correlation was observed with BRS. In ICD recipients with well-compensated heart failure, autonomic markers derived from BRS, HRV, and MIBG studies are related to FVAE. These markers have limited inter-dependency and constitute useful means for SCD risk stratification in this subgroup of patients. (author)

The effect of malaria and anti-malarial drugs on skeletal and cardiac muscles.

Science.gov (United States)

Marrelli, Mauro Toledo; Brotto, Marco

2016-11-02

Malaria remains one of the most important infectious diseases in the world, being a significant public health problem associated with poverty and it is one of the main obstacles to the economy of an endemic country. Among the several complications, the effects of malaria seem to target the skeletal muscle system, leading to symptoms, such as muscle aches, muscle contractures, muscle fatigue, muscle pain, and muscle weakness. Malaria cause also parasitic coronary artery occlusion. This article reviews the current knowledge regarding the effect of malaria disease and the anti-malarial drugs on skeletal and cardiac muscles. Research articles and case report publications that addressed aspects that are important for understanding the involvement of malaria parasites and anti-malarial therapies affecting skeletal and cardiac muscles were analysed and their findings summarized. Sequestration of red blood cells, increased levels of serum creatine kinase and reduced muscle content of essential contractile proteins are some of the potential biomarkers of the damage levels of skeletal and cardiac muscles. These biomarkers might be useful for prevention of complications and determining the effectiveness of interventions designed to protect cardiac and skeletal muscles from malaria-induced damage.

PET and SPET tracers for mapping the cardiac nervous system

International Nuclear Information System (INIS)

Langer, Oliver; Halldin, Christer

2002-01-01

The human cardiac nervous system consists of a sympathetic and a parasympathetic branch with (-)-norepinephrine and acetylcholine as the respective endogenous neurotransmitters. Dysfunction of the cardiac nervous system is implicated in various types of cardiac disease, such as heart failure, myocardial infarction and diabetic autonomic neuropathy. In vivo assessment of the distribution and function of cardiac sympathetic and parasympathetic neurones with positron emission tomography (PET) and single-photon emission tomography (SPET) can be achieved by means of a number of carbon-11-, fluorine-18-, bromine-76- and iodine-123-labelled tracer molecules. Available tracers for mapping sympathetic neurones can be divided into radiolabelled catecholamines, such as 6-[ 18 F]fluorodopamine, (-)-6-[ 18 F]fluoronorepinephrine and (-)-[ 11 C]epinephrine, and radiolabelled catecholamine analogues, such as [ 123 I]meta-iodobenzylguanidine, [ 11 C]meta-hydroxyephedrine, [ 18 F]fluorometaraminol, [ 11 C]phenylephrine and meta-[ 76 Br]bromobenzylguanidine. Resistance to metabolism by monoamine oxidase and catechol-O-methyl transferase simplifies the myocardial kinetics of the second group. Both groups of compounds are excellent agents for an overall assessment of sympathetic innervation. Biomathematical modelling of tracer kinetics is complicated by the complexity of the steps governing neuronal uptake, retention and release of these agents as well as by their high neuronal affinity, which leads to partial flow dependence of uptake. Mapping of cardiac parasympathetic neurones is limited by a low density and focal distribution pattern of these neurones in myocardium. Available tracers are derivatives of vesamicol, a molecule that binds to a receptor associated with the vesicular acetylcholine transporter. Compounds like (-)-[ 18 F]fluoroethoxybenzovesamicol display a high degree of non-specific binding in myocardium which restricts their utility for cardiac neuronal imaging. (orig.)

Analysis of autonomic modulation of heart rate in patients with Parkinson's disease and elderly individuals submitted to game therapy training.

Science.gov (United States)

Rocha, Rodrigo Santiago Barbosa; De Oliveira Rocha, Larissa Salgado; Pena, Elza Sara Maués; Caldas, Laiz Cristinna Ponce; Moreno, Marlene Aparecida

2018-01-01

Elderly patients and individuals with Parkinson's disease have a reduction in autonomic heart rate modulation, which may influence the survival of these patients, and rehabilitation can minimize this event. We tested the hypothesis that rehabilitation protocol with game console would influence the cardiac autonomic modulation of patients with Parkinson's Disease. Eight-seven volunteers were divided into two groups, control (n = 45) and Parkinson's (n = 42), they completed the study 40 volunteers in the control group (CG) and 31 patients in the Parkinson group (PG), and subjected to 24 sessions of game therapy physiotherapy, thrice a week. Analysis of autonomic HR modulation was conducted before and after the rehabilitation program using a Polar RS800CX HR sensor. For the analysis of heart rate variability the data were transferred to the Kubios HRV 2.2 program. Statistical analysis was performed in the Biostat 5.2 program, the comparison of the data by ANOVA followed by Tukey test, and the general characteristics by the chi-square test. The critical value for rejecting the null hypothesis was set at P modulation of HR values. Subjects with PD exhibit less autonomic modulation of HR and the rehabilitation protocol with game therapy improved autonomic modulation of HR. Geriatr Gerontol Int 2018; 18: 20-25. © 2017 Japan Geriatrics Society.

Differential cardiac effects in rats exposed to atmospheric smog generated from isoprene versus toluene

Science.gov (United States)

The results of this study demonstrate that atmospheric smog generated from both isoprene and toluene cause cardiac effects in rats. In addition, it appears that smog from toluene is more toxic in terms of cardiac arrhythmogenicity. Smog, which is a comple...

Evaluation of cardiovascular autonomic nervous functions in diabetics: Study in a rural teaching hospital

Directory of Open Access Journals (Sweden)

Ashutosh Pathak

2017-01-01

Full Text Available Introduction: Cardiovascular autonomic neuropathy (CAN is a least understood complication of diabetes which is often underdiagnosed. It causes resting tachycardia, orthostatic hypotension, and exercise intolerance and is associated with higher cardiovascular mortality in diabetic patients. This stresses the need of early diagnosis of CAN to prevent higher mortality rates. Materials and Methods: Fifty cases of diabetes mellitus with no clinical evidence of cardiac disease were subjected to cardiac autonomic function (CAF tests according to Ewing's criteria which included heart rate (HR variability during deep breathing, Valsalva maneuver ratio, HR response on standing, blood pressure (BP response to standing, and BP response to sustained handgrip to find the prevalence of CAN. Results: In this study, among 100 patients (50 case and 50 control, we found CAN in 52%. Out of which, parasympathetic neuropathy was seen in 52% of cases, and sympathetic neuropathy was seen in 26% of cases. CAF tests of HR variability during deep breathing, Valsalva maneuver ratio, HR response to standing, BP response to standing, and BP response to sustained handgrip found abnormal response in 68%, 40%, 52%, 12%, and 14%, respectively. Diabetic retinopathy and nephropathy were significantly associated with CAN (P = 0.0001, S. Conclusion: Prevalence of CAN among diabetics was 52%, and parasympathetic CAF tests are more sensitive for the detection of CAN than sympathetic CAF tests. Development of CAN in diabetic patients may lead to increased morbidity; thence, they should be routinely evaluated for CAN using these bedside tests.

Effect of myocardial perfusion and metabolic interventions on cardiac kinetics of phenylpentadecanoic acid (IPPA) I 123

Energy Technology Data Exchange (ETDEWEB)

Reske, S.N.; Schoen, S.; Schmitt, W.; Knopp, R.; Winkler, C.; Machulla, H.J.

1986-08-01

The effect of regional myocardial perfusion and flow-independent adrenergic stimulation, as well as lactate-mediated inhibition of cardiac lipolysis, on cardiac IPPA uptake and metabolism was examined in canine hearts (flow studies) and in the isolated perfused Langendorff rat heart (metabolic interventions). In both normal and ischaemic myocardium, local perfusion is a major determinant of cardiac IPPA uptake. In pacing-induced hyperaemia, the strict flow-dependence of cardiac IPPA uptake is not preserved. Adrenergic stimulation raises the rate of oxidation of both palmitic acid /sup 14/C and IPPA. This change is reflected by increased metabolite production released into the perfusate and radioactivity clearance recorded externally. Lactate in high concentrations exerts the opposite effect on cardiac free fatty acid oxidation. IPPA is stored in this condition preferentially in tissue phospholipids and triglycerides.

Effect of myocardial perfusion and metabolic interventions on cardiac kinetics of phenylpentadecanoic acid (IPPA) I 123

International Nuclear Information System (INIS)

Reske, S.N.; Schoen, S.; Schmitt, W.; Knopp, R.; Winkler, C.; Machulla, H.J.

1986-01-01

The effect of regional myocardial perfusion and flow-independent adrenergic stimulation, as well as lactate-mediated inhibition of cardiac lipolysis, on cardiac IPPA uptake and metabolism was examined in canine hearts (flow studies) and in the isolated perfused Langendorff rat heart (metabolic interventions). In both normal and ischaemic myocardium, local perfusion is a major determinant of cardiac IPPA uptake. In pacing-induced hyperaemia, the strict flow-dependence of cardiac IPPA uptake is not preserved. Adrenergic stimulation raises the rate of oxidation of both palmitic acid 14 C and IPPA. This change is reflected by increased metabolite production released into the perfusate and radioactivity clearance recorded externally. Lactate in high concentrations exerts the opposite effect on cardiac free fatty acid oxidation. IPPA is stored in this condition preferentially in tissue phospholipids and triglycerides. (orig.)

The Human Element and Autonomous Ships

Directory of Open Access Journals (Sweden)

Sauli Ahvenjärvi

2016-09-01

Full Text Available The autonomous ship technology has become a “hot” topic in the discussion about more efficient, environmentally friendly and safer sea transportation solutions. The time is becoming mature for the introduction of commercially sensible solutions for unmanned and fully autonomous cargo and passenger ships. Safety will be the most interesting and important aspect in this development. The utilization of the autonomous ship technology will have many effects on the safety, both positive and negative. It has been announced that the goal is to make the safety of an unmanned ship better that the safety of a manned ship. However, it must be understood that the human element will still be present when fully unmanned ships are being used. The shore-based control of a ship contains new safety aspects and an interesting question will be the interaction of manned and unmanned ships in the same traffic area. The autonomous ship technology should therefore be taken into account on the training of seafarers. Also it should not be forgotten that every single control algorithm and rule of the internal decision making logic of the autonomously navigating ship has been designed and coded by a human software engineer. Thus the human element is present also in this point of the lifetime navigation system of the autonomous ship.

Role of interleukin-6 levels in cardiovascular autonomic dysfunction in type 2 diabetic patients

Energy Technology Data Exchange (ETDEWEB)

Shinohara, Tetsuji; Takahashi, Naohiko; Kakuma, Tetsuya; Hara, Masahide; Yoshimatsu, Hironobu [Oita University, Department of Internal Medicine 1, Faculty of Medicine, Yuhu, Oita (Japan); Yufu, Kunio; Anan, Futoshi; Nakagawa, Mikiko; Saikawa, Tetsunori [Oita University, Department of Cardiovascular Science, Oita (Japan)

2008-09-15

Increased serum interleukin-6 (IL-6) levels are associated with an increased risk of cardiovascular disease, and cardiovascular autonomic dysfunction is associated with high mortality in type 2 diabetic patients. However, the relationship between IL-6 levels and cardiovascular autonomic dysfunction has not been fully elucidated. The aim of this study was to determine whether serum IL-6 levels are associated with cardiovascular autonomic dysfunction in type 2 diabetic patients. Eighty type 2 diabetic patients who did not have organic heart disease were categorized into a high IL-6 group (>2.5 pg/ml, n= 0, age 59{+-}12 years) or a non-high IL-6 group (<2.5 pg/ml, n=40, 61{+-}12 years). Cardiac autonomic function was assessed by baroreflex sensitivity, heart rate variability, plasma norepinephrine concentrations and {sup 123}I-metaiodobenzylguanidine (MIBG) scintigraphy. The body mass index values (BMI), fasting insulin levels and homeostasis model assessment index values were higher in the high IL-6 group than in the non-high IL-6 group (p<0.01). Early and delayed {sup 123}I-MIBG myocardial uptake values were lower (p<0.01), and the percent washout rate of {sup 123}I-MIBG was higher (p<0.05) in the high IL-6 group than in the non-high IL-6 group. Furthermore, multiple regression analysis revealed that the IL-6 level was independently predicted by the BMI and the myocardial uptake of {sup 123}I-MIBG during the delayed phase. The results indicate that elevated IL-6 levels are associated with depressed cardiovascular autonomic function and obesity in type 2 diabetic patients. (orig.)

More Effective Use of Urban Space by Autonomous Double Parking

Directory of Open Access Journals (Sweden)

Rafael Estepa

2017-01-01

Full Text Available The new capabilities of autonomous cars can be used to mitigate to a large extent safety concerns and nuisance traditionally associated with double parking. In this paper double parking for autonomous cars is proposed as a new approach to temporarily increase parking capacity in locations in clear need for extra provision when best alternatives cannot be found. The basic requirements, operation, and procedures of the proposed solution are outlined. A curbside parking has been simulated implementing the suggested double parking operation and important advantages have been identified for drivers, the environment, and the city. Double parking can increase over 50% the parking capacity of a given area. Autonomous car owners would (at least double their probabilities of finding parking compared to traditional drivers, saving cruising time and emissions. However, significant work and technological advances are still needed in order to make this feasible in the near future.

Autonomic nervous system mediated effects of food intake. Interaction between gastrointestinal and cardiovascular systems.

NARCIS (Netherlands)

van Orshoven, N.P.

2008-01-01

The studies presented in this thesis focused on the autonomic nervous system mediated interactions between the gastrointestinal and cardiovascular systems in response to food intake and on potential consequences of failure of these interactions. The effects of food intake on cardiovascular

Chronic hydrocephalus-induced changes in cerebral blood flow: mediation through cardiac effects.

Science.gov (United States)

Dombrowski, Stephen M; Schenk, Soren; Leichliter, Anna; Leibson, Zack; Fukamachi, Kiyotaka; Luciano, Mark G

2006-10-01

Decreased cerebral blood flow (CBF) in hydrocephalus is believed to be related to increased intracranial pressure (ICP), vascular compression as the result of enlarged ventricles, or impaired metabolic activity. Little attention has been given to the relationship between cardiac function and systemic blood flow in chronic hydrocephalus (CH). Using an experimental model of chronic obstructive hydrocephalus developed in our laboratory, we investigated the relationship between the duration and severity of hydrocephalus and cardiac output (CO), CBF, myocardial tissue perfusion (MTP), and peripheral blood flow (PBF). Blood flow measures were obtained using the microsphere injection method under controlled hemodynamic conditions in experimental CH (n=23) and surgical control (n=8) canines at baseline and at 2, 4, 8, 12, and 16 weeks. Cardiac output measures were made using the Swan-Ganz thermodilution method. Intracranial compliance (ICC) via cerebrospinal fluid (CSF) bolus removal and infusion, and oxygen delivery in CSF and prefrontal cortex (PFC) were also investigated. We observed an initial surgical effect relating to 30% CO reduction and approximately 50% decrease in CBF, MTP, and PBF in both groups 2 weeks postoperatively, which recovered in control animals but continued to decline further in CH animals at 16 weeks. Cerebral blood flow, which was positively correlated with CO (P=0.028), showed no significant relationship with either CSF volume or pressure. Decreased CBF correlated with oxygen deprivation in PFC (P=0.006). Cardiac output was inversely related with ventriculomegaly (P=0.019), but did not correlate with ICP. Decreased CO corresponded to increased ICC, as measured by CSF infusion (P=0.04). Our results suggest that CH may have more of an influence on CO and CBF in the chronic stage than in the early condition, which was dominated by surgical effect. The cause of this late deterioration of cardiac function in hydrocephalus is uncertain, but may reflect

Autonomous Motivation and Fruit/Vegetable Intake in Parent–Adolescent Dyads

Science.gov (United States)

Dwyer, Laura A.; Bolger, Niall; Laurenceau, Jean-Philippe; Patrick, Heather; Oh, April Y.; Nebeling, Linda C.; Hennessy, Erin

2017-01-01

Introduction Autonomous motivation (motivation to engage in a behavior because of personal choice, interest, or value) is often associated with health behaviors. The present study contributes to research on motivation and eating behaviors by examining: (1) how autonomous motivation is correlated within parent–adolescent dyads; and (2) whether parent- and adolescent-reported autonomous motivation predicts the parent–adolescent correlation in fruit and vegetable (FV) intake frequency. Methods Data were drawn from the Family Life, Activity, Sun, Health, and Eating (FLASHE) Study, a cross-sectional U.S. survey of parent–adolescent dyads led by the National Cancer Institute and fielded between April and October 2014. In 2016, data were analyzed from dyads who had responses on a six-item self-report measure of daily frequency of FV consumption and a two-item self-report measure of autonomous motivation for consuming FVs. Results Parents' and adolescents' reports of autonomous motivation and FV intake frequency were positively correlated. Both parents' and adolescents' autonomous motivation predicted higher levels of their own FV intake frequency and that of their dyad partner (p-values ≤0.001). These effects of autonomous motivation explained 22.6% of the parent–adolescent correlation in FV intake frequency. Actor effects (one's motivation predicting their own FV intake frequency) were stronger than partner effects (one's motivation predicting their partner's FV intake frequency). Conclusions Parent–adolescent similarity in autonomous motivation for healthy eating may contribute to similarity in eating behaviors. Future research should further examine how individual-level health behavior correlates influence health behaviors within dyads. PMID:28526363

Autonomous Motivation and Fruit/Vegetable Intake in Parent-Adolescent Dyads.

Science.gov (United States)

Dwyer, Laura A; Bolger, Niall; Laurenceau, Jean-Philippe; Patrick, Heather; Oh, April Y; Nebeling, Linda C; Hennessy, Erin

2017-06-01

Autonomous motivation (motivation to engage in a behavior because of personal choice, interest, or value) is often associated with health behaviors. The present study contributes to research on motivation and eating behaviors by examining (1) how autonomous motivation is correlated within parent-adolescent dyads and (2) whether parent- and adolescent-reported autonomous motivation predicts the parent-adolescent correlation in fruit and vegetable (FV) intake frequency. Data were drawn from the Family Life, Activity, Sun, Health, and Eating (FLASHE) Study, a cross-sectional U.S. survey of parent-adolescent dyads led by the National Cancer Institute and fielded between April and October 2014. In 2016, data were analyzed from dyads who had responses on a six-item self-report measure of daily frequency of FV consumption and a two-item self-report measure of autonomous motivation for consuming FVs. Parents' and adolescents' reports of autonomous motivation and FV intake frequency were positively correlated. Both parents' and adolescents' autonomous motivation predicted higher levels of their own FV intake frequency and that of their dyad partner (p-values ≤0.001). These effects of autonomous motivation explained 22.6% of the parent-adolescent correlation in FV intake frequency. Actor effects (one's motivation predicting their own FV intake frequency) were stronger than partner effects (one's motivation predicting their partner's FV intake frequency). Parent-adolescent similarity in autonomous motivation for healthy eating may contribute to similarity in eating behaviors. Future research should further examine how individual-level health behavior correlates influence health behaviors within dyads. Published by Elsevier Inc.

Effects of short-term carvedilol on the cardiac sympathetic activity assessed by {sup 123}I-MIBG scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Miranda, Sandra Marina Ribeiro de; Mesquita, Evandro Tinoco; Freire, Fabiano de Lima; Ribeiro, Mario Luiz; Nobrega, Antonio Claudio Lucas da; Mesquita, Claudio Tinoco, E-mail: sandramarina@cardiol.b [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Azevedo, Jader Cunha; Barbirato, Gustavo Borges; Coimbra, Alexandro [Hospital Pro-Cardiaco, Rio de Janeiro, RJ (Brazil); Dohmann, Hans Fernando da Rocha [Centro de Ensino e Pesquisa do Pro-Cardiaco (PROCEP), Rio de Janeiro, RJ (Brazil)

2010-03-15

Background: autonomic alterations in heart failure are associated with an increase in morbimortality. Several noninvasive methods have been employed to evaluate the sympathetic function, including the Meta-Iodobenzylguanidine ({sup 123}I-MIBG) scintigraphy imaging of the heart. Objective: to evaluate the cardiac sympathetic activity through {sup 123}I-MIBG scintigraphy, before and after three months of carvedilol therapy in patients with heart failure and left ventricular ejection fraction (LVEF) < 45%. Patients and methods: sixteen patients, aged 56.3 +- 12.6 years (11 males), with a mean LVEF of 28% +- 8% and no previous use of beta-blockers were recruited for the study. Images of the heart innervation were acquired with {sup 123}I-MIBG, and the serum levels of catecholamines (epinephrine, dopamine and norepinephrine) were measured; the radioisotope ventriculography (RIV) was performed before and after a three-month therapy with carvedilol. Results: patients' functional class showed improvement: before the treatment, 50% of the patients were FC II and 50% were FC III. After 3 months, 7 patients were FC I (43.8%) and 9 were FC II (56.2%), (rho = 0.0001). The mean LVEF assessed by RIV increased from 29% to 33% (rho = 0.017). There was no significant variation in cardiac adrenergic activity assessed by {sup 123}I-MIBG (early and late resting images and washout rate). No significant variation was observed regarding the measurement of catecholamines. Conclusion: the short-term treatment with carvedilol promoted the clinical and LVEF improvement. However, this was not associated to an improvement in the cardiac adrenergic activity, assessed by {sup 123}I-MIBG scintigraphy, as well as the measurement of circulating catecholamines. (author)

Autonomic correlates at rest and during evoked attention in children with attention-deficit/hyperactivity disorder and effects of methylphenidate.

Science.gov (United States)

Negrao, Bianca Lee; Bipath, Priyesh; van der Westhuizen, Deborah; Viljoen, Margaretha

2011-01-01

The aim of this study was to assess autonomic nervous system functioning in children with attention-deficit/hyperactivity disorder (ADHD) and to examine the effects of methylphenidate and focussed attention. Children with ADHD (n = 19) were tested while they were stimulant free and during a period in which they were on stimulants. On both occasions, autonomic nervous system functioning was tested at baseline and during focussed attention. Autonomic nervous system functioning of control subjects was also tested at baseline and during focussed attention. Autonomic nervous system activity was determined by means of heart rate variability (HRV) and skin conductivity analyses. Attention was evoked by means of the BioGraph Infiniti biofeedback apparatus. HRV was determined by time domain, frequency domain and Poincaré analysis of RR interval data. Skin conductivity was determined by the BioGraph Infiniti biofeedback apparatus. The main findings of this study were (a) that stimulant-free children with ADHD showed a sympathetic underarousal and parasympathetic overarousal of the sympathovagal balance relative to control subjects; (b) methylphenidate shifted the autonomic balance of children with ADHD towards normal levels; however, a normal autonomic balance was not reached, and (c) stimulant-free children with ADHD exhibited a shift in the sympathovagal balance towards the sympathetic nervous system from baseline to focussed attention; however, methylphenidate appeared to abolish this shift. Stimulant-free children with ADHD have a parasympathetic dominance of the autonomic balance, relative to control subjects. Methylphenidate attempts to restore the normal autonomic balance in children with ADHD, but inhibits the normal autonomic nervous system response to a cognitive challenge. These results indicate that methylphenidate may have a suppressive effect on the normal stress response. Although this may be of benefit to those who interact with children who suffer from ADHD

Relationships between thermic effect of food, insulin resistance and autonomic nervous activity.

Science.gov (United States)

Watanabe, Tomonori; Nomura, Masahiro; Nakayasu, Kimiko; Kawano, Tomohito; Ito, Susumu; Nakaya, Yutaka

2006-02-01

The thermic effect of food (TEF) is higher in lean than in obese human subjects. Relationships between TEF and insulin resistance during meals, from the point of view of autonomic nervous activity, were evaluated. Autonomic nervous activity was evaluated in 20 young adults using the spectral analysis of heart rate variability from one hour before to two hours after a meal. Heart rate data were analyzed based on low frequency components (LF power, 0.04-0.15 Hz), high frequency components (HF power, 0.15-0.40 Hz), and LF/HF ratios. Energy expenditure and the TEF were measured 30 min after a meal. Homeostasis model of insulin resistance index (HOMA-IR) was also measured. The LF/HF ratio was significantly increased 30 min after a meal (pinsulin sensitivity induces a poor response of sympathetic nervous activity in the postprandial phase and a reduction in postprandial energy expenditure.

Cardioprotective Effects of Tualang Honey: Amelioration of Cholesterol and Cardiac Enzymes Levels

OpenAIRE

Khalil, Md. Ibrahim; Tanvir, E. M.; Afroz, Rizwana; Sulaiman, Siti Amrah; Gan, Siew Hua

2015-01-01

The present study was designed to investigate the cardioprotective effects of Malaysian Tualang honey against isoproterenol- (ISO-) induced myocardial infarction (MI) in rats by investigating changes in the levels of cardiac marker enzymes, cardiac troponin I (cTnI), triglycerides (TG), total cholesterol (TC), lipid peroxidation (LPO) products, and antioxidant defense system combined with histopathological examination. Male albino Wistar rats (n = 40) were pretreated orally with Tualang honey...

Effects of Caloric Restriction on Cardiac Oxidative Stress and Mitochondrial Bioenergetics: Potential Role of Cardiac Sirtuins

Directory of Open Access Journals (Sweden)

Ken Shinmura

2013-01-01

Full Text Available The biology of aging has not been fully clarified, but the free radical theory of aging is one of the strongest aging theories proposed to date. The free radical theory has been expanded to the oxidative stress theory, in which mitochondria play a central role in the development of the aging process because of their critical roles in bioenergetics, oxidant production, and regulation of cell death. A decline in cardiac mitochondrial function associated with the accumulation of oxidative damage might be responsible, at least in part, for the decline in cardiac performance with age. In contrast, lifelong caloric restriction can attenuate functional decline with age, delay the onset of morbidity, and extend lifespan in various species. The effect of caloric restriction appears to be related to a reduction in cellular damage induced by reactive oxygen species. There is increasing evidence that sirtuins play an essential role in the reduction of mitochondrial oxidative stress during caloric restriction. We speculate that cardiac sirtuins attenuate the accumulation of oxidative damage associated with age by modifying specific mitochondrial proteins posttranscriptionally. Therefore, the distinct role of each sirtuin in the heart subjected to caloric restriction should be clarified to translate sirtuin biology into clinical practice.

Heart Rate Variability and Autonomic Modulations in Preeclampsia.

Directory of Open Access Journals (Sweden)

Shaza M Musa

Full Text Available Although the exact pathophysiology of preeclampsia is not well understood, autonomic nervous system imbalance is suggested as one of the main factors.To investigate heart rate variability (HRV and autonomic modulations in Sudanese pregnant women with preeclampsia.A case-control study (60 women in each arm was conducted at Omdurman Maternity Hospital-Sudan, during the period from June to August, 2014. Cases were women presented with preeclampsia and healthy pregnant women were the controls. Studied groups were matched for important determinants of HRV. Natural logarithm (Ln of total power (TP, high frequency (HF, low frequency (LF and very low frequency (VLF were used to determine HRV. Normalized low and high frequencies (LF Norm and HF Norm were used to evaluate sympathetic and parasympathetic autonomic modulations respectively.Patients with preeclampsia achieved significantly higher LF Norm [49.80 (16.25 vs. 44.55 (19.15, P = 0.044] and LnLF/HF [0.04 (0.68 vs. -0.28 (0.91, P = 0.023] readings, but lower HF Norm [49.08 (15.29 vs. 55.87 (19.56, P = 0.012], compared with healthy pregnant women. Although all other HRV measurements were higher in the patients with preeclampsia compared with the controls, only LnVLF [4.50 (1.19 vs. 4.01 (1.06, P = 0.017] and LnLF [4.01 (1.58 vs. 3.49 (1.23, P = 0.040] reached statistical significance.The study adds further evidence for the dominant cardiac sympathetic modulations on patients with preeclampsia, probably secondary to parasympathetic withdrawal in this group. However, the higher LnVLF and LnLF readings achieved by preeclamptic women compared with the controls are unexpected in the view that augmented sympathetic modulations usually depresses all HRV parameters including these two measures.

Cold Regions Issues for Off-Road Autonomous Vehicles

Science.gov (United States)

2004-04-01

the operation of off-road autonomous vehicles . Low-temperature effects on lubricants, materials, and batteries can impair a robot’s ability to operate...demanding that off-road autonomous vehicles must be designed for and tested in cold regions if they are expected to operate there successfully.

Automatic recognition of cardiac arrhythmias based on the geometric patterns of Poincaré plots

International Nuclear Information System (INIS)

Zhang, Lijuan; Guo, Tianci; Xi, Bin; Fan, Yang; Wang, Kun; Bi, Jiacheng; Wang, Ying

2015-01-01

The Poincaré plot emerges as an effective tool for assessing cardiovascular autonomic regulation. It displays nonlinear characteristics of heart rate variability (HRV) from electrocardiographic (ECG) recordings and gives a global view of the long range of ECG signals. In the telemedicine or computer-aided diagnosis system, it would offer significant auxiliary information for diagnosis if the patterns of the Poincaré plots can be automatically classified. Therefore, we developed an automatic classification system to distinguish five geometric patterns of the Poincaré plots from four types of cardiac arrhythmias. The statistics features are designed on measurements and an ensemble classifier of three types of neural networks is proposed. Aiming at the difficulty to set a proper threshold for classifying the multiple categories, the threshold selection strategy is analyzed. 24 h ECG monitoring recordings from 674 patients, which have four types of cardiac arrhythmias, are adopted for recognition. For comparison, Support Vector Machine (SVM) classifiers with linear and Gaussian kernels are also applied. The experiment results demonstrate the effectiveness of the extracted features and the better performance of the designed classifier. Our study can be applied to diagnose the corresponding sinus rhythm and arrhythmia substrates disease automatically in the telemedicine and computer-aided diagnosis system. (paper)

Adverse cardiac effects of exogenous angiotensin 1-7 in rats with subtotal nephrectomy are prevented by ACE inhibition.

Directory of Open Access Journals (Sweden)

Louise M Burrell

Full Text Available We previously reported that exogenous angiotensin (Ang 1-7 has adverse cardiac effects in experimental kidney failure due to its action to increase cardiac angiotensin converting enzyme (ACE activity. This study investigated if the addition of an ACE inhibitor (ACEi to Ang 1-7 infusion would unmask any beneficial effects of Ang 1-7 on the heart in experimental kidney failure. Male Sprague-Dawley rats underwent subtotal nephrectomy (STNx and were treated with vehicle, the ACEi ramipril (oral 1mg/kg/day, Ang 1-7 (subcutaneous 24 μg/kg/h or dual therapy (all groups, n = 12. A control group (n = 10 of sham-operated rats were also studied. STNx led to hypertension, renal impairment, cardiac hypertrophy and fibrosis, and increased both left ventricular ACE2 activity and ACE binding. STNx was not associated with changes in plasma levels of ACE, ACE2 or angiotensin peptides. Ramipril reduced blood pressure, improved cardiac hypertrophy and fibrosis and inhibited cardiac ACE. Ang 1-7 infusion increased blood pressure, cardiac interstitial fibrosis and cardiac ACE binding compared to untreated STNx rats. Although in STNx rats, the addition of ACEi to Ang 1-7 prevented any deleterious cardiac effects of Ang 1-7, a limitation of the study is that the large increase in plasma Ang 1-7 with ramipril may have masked any effect of infused Ang 1-7.

Representations of relatedness with parents and friends and autonomous academic motivation during the late adolescence-early adulthood period: reciprocal or unidirectional effects?

Science.gov (United States)

Guay, Frédéric; Marsh, Herbert W; Senécal, Caroline; Dowson, Martin

2008-12-01

The literature on the determinants of academic motivation indicates that social and affective processes connected to students' interpersonal relationships are central elements in understanding students' academic motivation and other school-related outcomes. The aim of this study was to answer the following questions: Does autonomous motivation drive representations of relatedness, do representations of relatedness drive autonomous motivation, or are these constructs reciprocally related over time? The sample consists of 834 adolescents aged 18 years (SD=1.88) who participated in a 3-year longitudinal study. Results from the structural equation models provided good support for the effect of representations of relatedness with parents on autonomous academic motivation but no convincing support for the effect of motivation on representations of relatedness with parents. In addition, no significant effect in either direction was found between representations of relatedness with friends and autonomous academic motivation. It might be important to inform parents that they may still have an influence on their adolescent's representations of relatedness and subsequently on his/her autonomous academic motivation even during the late adolescence-early adulthood period, a period when some parents may be tempted to believe that they can do little to motivate their offspring.

Effects of Growth Hormone on Cardiac Remodeling During Resistance Training in Rats

Energy Technology Data Exchange (ETDEWEB)

Junqueira, Adriana, E-mail: francispacagnelli@unoeste.br [Universidade do Oeste Paulista (UNOESTE), Presidente Prudente, SP (Brazil); Cicogna, Antônio Carlos [Universidade Estadual Paulista (UNESP), Campus Botucatu, SP (Brazil); Engel, Letícia Estevam; Aldá, Maiara Almeida [Universidade do Oeste Paulista (UNOESTE), Presidente Prudente, SP (Brazil); Tomasi, Loreta Casquel de [Universidade Estadual Paulista (UNESP), Campus Botucatu, SP (Brazil); Giuffrida, Rogério; Giometti, Inês Cristina [Universidade do Oeste Paulista (UNOESTE), Presidente Prudente, SP (Brazil); Freire, Ana Paula Coelho Figueira [Universidade do Oeste Paulista (UNOESTE), Presidente Prudente, SP (Brazil); Universidade Estadual Paulista (UNESP), Campus Presidente Prudente, SP (Brazil); Aguiar, Andreo Fernando [Universidade do Norte do Paraná, UNOPAR, Londrina, PR (Brazil); Pacagnelli, Francis Lopes [Universidade do Oeste Paulista (UNOESTE), Presidente Prudente, SP (Brazil)

2016-01-15

Although the beneficial effects of resistance training (RT) on the cardiovascular system are well established, few studies have investigated the effects of the chronic growth hormone (GH) administration on cardiac remodeling during an RT program. To evaluate the effects of GH on the morphological features of cardiac remodeling and Ca2+ transport gene expression in rats submitted to RT. Male Wistar rats were divided into 4 groups (n = 7 per group): control (CT), GH, RT and RT with GH (RTGH). The dose of GH was 0.2 IU/kg every other day for 30 days. The RT model used was the vertical jump in water (4 sets of 10 jumps, 3 bouts/wk) for 30 consecutive days. After the experimental period, the following variables were analyzed: final body weight (FBW), left ventricular weight (LVW), LVW/FBW ratio, cardiomyocyte cross-sectional area (CSA), collagen fraction, creatine kinase muscle-brain fraction (CK-MB) and gene expressions of SERCA2a, phospholamban (PLB) and ryanodine (RyR). There was no significant (p > 0.05) difference among groups for FBW, LVW, LVW/FBW ratio, cardiomyocyte CSA, and SERCA2a, PLB and RyR gene expressions. The RT group showed a significant (p < 0.05) increase in collagen fraction compared to the other groups. Additionally, the trained groups (RT and RTGH) had greater CK-MB levels compared to the untrained groups (CT and GH). GH may attenuate the negative effects of RT on cardiac remodeling by counteracting the increased collagen synthesis, without affecting the gene expression that regulates cardiac Ca{sup 2+} transport.

Effect of fast-track cardiac anesthesia on myocardial oxidative damage, inflammation and nerve related peptides of patients undergoing cardiac operation

Directory of Open Access Journals (Sweden)

Xing-Tao Cai

2016-01-01

Full Text Available Objective: To study the effect of fast-track cardiac anesthesia on myocardial oxidative damage, inflammation and nerve related peptides of patients undergoing cardiac operation. Methods: Sixty patients with rheumatic heart disease undergoing heart valve surgery were randomly divided into the fast track group (n=30 and conventional group (n=30. Then myocardial injury indicators, mitochondrial oxidative stress indicators, inflammation indicators and nerverelated peptides of both groups were analyzed. Results: cTnI contents at T2-T4 points in time of both groups showed an increasing trend and the increasing trend of fast track group was weaker than that of conventional group; SOD contents as well as mitochondrial tristate respiratory function, respiratory control ratios and phosphorus oxygen ratios in myocardial tissue of fast track group were higher than those of conventional group, and MDA contents was lower than those of conventional group; plasma TNF-α, IL-6, IL-8, NSE, S100β and Aβ contents of fast track group were lower than those of conventional group. Conclusions: Fasttrack cardiac anesthesia can protect myocardial cells, reduce mitochondrial oxidative stress, relieve inflammation and improve nerve function; it is an ideal anesthesia method for cardiac operation.

Protective effects of isorhynchophylline on cardiac arrhythmias in rats and guinea pigs.

Science.gov (United States)

Gan, Runtao; Dong, Guo; Yu, Jiangbo; Wang, Xu; Fu, Songbin; Yang, Shusen

2011-09-01

As one important constituent extracted from a traditional Chinese medicine, Uncaria Rhynchophylla Miq Jacks, isorhynchophylline has been used to treat hypertension, epilepsy, headache, and other illnesses. Whether isorhynchophylline protects hearts against cardiac arrhythmias is still incompletely investigated. This study was therefore aimed to examine the preventive effects of isorhynchophylline on heart arrhythmias in guinea pigs and rats and then explore their electrophysiological mechanisms. In vivo, ouabain and calcium chloride were used to establish experimental arrhythmic models in guinea pigs and rats. In vitro, the whole-cell patch-lamp technique was used to study the effect of isorhynchophylline on action potential duration and calcium channels in acutely isolated guinea pig and rat cardiomyocytes. The dose of ouabain required to induce cardiac arrhythmias was much larger in guinea pigs administered with isorhynchophylline. Additionally, the onset time of cardiac arrhythmias induced by calcium chloride was prolonged, and the duration was shortened in rats pretreated with isorhynchophylline. The further study showed that isorhynchophylline could significantly decrease action potential duration and inhibit calcium currents in isolated guinea pig and rat cardiomyocytes in a dose-dependent manner. In summary, isorhynchophylline played a remarkably preventive role in cardiac arrhythmias through the inhibition of calcium currents in rats and guinea pigs. © Georg Thieme Verlag KG Stuttgart · New York.

The effectiveness of the cardiac resynchronization in a patient with ischemic cardiomyopathy

Directory of Open Access Journals (Sweden)

Diana R. Tudorașcu

2018-04-01

Full Text Available Cardiac resynchronization therapy (CRT in multiple and large trials has been demonstrated to improve symptoms and decrease hospitalization and mortality of patients when used in addition to optimal medical therapy. The global mechanical performance of the heart is affected in subjects with heart failure by atrio-ventricular, interventricular, or intraventricular conduction disorders, which lead to the desynchronization of electrical activity. Cardiac resynchronization therapy can effectively improve the clinical and haemodynamic status of these patients. According to literature data, CRT is performed only on well-selected patients (who qualify for CRT based on current indications, and approximately 70% of those patients respond favorably. We present the case of a patient responsive to cardiac resynchronization therapy which led to lowering of his NYHA classification and to improvement of left ventricle hemodynamics. The benefits of cardiac resynchronization therapy were multiple in this case, including improved tolerance to physical exercise and a decreased rate of hospitalization, which overall led to improved quality of life.

Diabetic retinopathy is associated with insulin resistance and cardiovascular autonomic dysfunction in type 2 diabetic patients

International Nuclear Information System (INIS)

Anan, Futoshi; Takayuki, Masaki; Takahashi, Naohiko; Nakagawa, Mikiko; Eshima, Nobuoki; Saikawa, Tetsunori; Yoshimatsu, Hironobu

2009-01-01

Diabetic retinopathy (DR) and cardiovascular autonomic dysfunction are associated with high mortality in type 2 diabetic patients. This preliminary study was therefore designed to test the hypothesis that DR is associated with insulin resistance and cardiovascular autonomic dysfunction in type 2 diabetic patients without insulin treatment. Seventy persons were diagnosed to have type 2 diabetes in the examination from June 2004 to May 2006. The study group consisted of 29 type 2 diabetic patients with DR (age: 58±6 years, mean±standard deviation (s.d.)) and 41 type 2 diabetic patients with no DR (NDR) (n=41, 58±5 years). Cardiovascular autonomic function was assessed by baroreflex sensitivity (BRS), heart rate variability, plasma norepinephrine concentration and cardiac 123 I-metaiodobenzylguanidine (MIBG) scintigraphic findings. DR patients had lower BRS, early and delayed 123 I-MIBG myocardial uptake values and higher percent washout rate (WR) of 123 I-MIBG than the NDR patients. With respect to metabolic findings, DR patients had higher fasting plasma insulin concentration (P 123 I-MIBG (P 123 I-MIBG are independently associated with DR in Japanese patients with type 2 diabetes mellitus. (author)

The effectiveness of and satisfaction with high-fidelity simulation to teach cardiac surgical resuscitation skills to nurses.

Science.gov (United States)

McRae, Marion E; Chan, Alice; Hulett, Renee; Lee, Ai Jin; Coleman, Bernice

2017-06-01

There are few reports of the effectiveness or satisfaction with simulation to learn cardiac surgical resuscitation skills. To test the effect of simulation on the self-confidence of nurses to perform cardiac surgical resuscitation simulation and nurses' satisfaction with the simulation experience. A convenience sample of sixty nurses rated their self-confidence to perform cardiac surgical resuscitation skills before and after two simulations. Simulation performance was assessed. Subjects completed the Satisfaction with Simulation Experience scale and demographics. Self-confidence scores to perform all cardiac surgical skills as measured by paired t-tests were significantly increased after the simulation (d=-0.50 to 1.78). Self-confidence and cardiac surgical work experience were not correlated with time to performance. Total satisfaction scores were high (mean 80.2, SD 1.06) indicating satisfaction with the simulation. There was no correlation of the satisfaction scores with cardiac surgical work experience (τ=-0.05, ns). Self-confidence scores to perform cardiac surgical resuscitation procedures were higher after the simulation. Nurses were highly satisfied with the simulation experience. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Betel chewing on the central and autonomic nervous systems.

Science.gov (United States)

Chu, N S

2001-01-01

Betel chewing has been claimed to produce a sense of well-being, euphoria, heightened alertness, sweating, salivation, a hot sensation in the body and increased capacity to work. Betel chewing also leads to habituation, addiction and withdrawal. However, the mechanisms underlying these effects remain poorly understood. Arecoline, the major alkaloid of Areca nut, has been extensively studied, and several effects of betel chewing are thought to be related to the actions of this parasympathomimetic constituent. However, betel chewing may produce complex reactions and interactions. In the presence of lime, arecoline and guvacoline in Areca nut are hydrolyzed into arecaidine and guvacine, respectively, which are strong inhibitors of GABA uptake. Piper betle flower or leaf contains aromatic phenolic compounds which have been found to stimulate the release of catecholamines in vitro. Thus, betel chewing may affect parasympathetic, GABAnergic and sympathetic functions. Betel chewing produces an increase in heart rate, blood pressure, sweating and body temperature. In addition, EEG shows widespread cortical desynchronization indicating a state of arousal. In autonomic function tests, both the sympathetic skin response and RR interval variation are affected. Betel chewing also increases plasma concentrations of norepinephrine and epinephrine. These results suggest that betel chewing mainly affects the central and autonomic nervous systems. Future studies should investigate both the acute and chronic effects of betel chewing. Such studies may further elucidate the psychoactive mechanisms responsible for the undiminished popularity of betel chewing since antiquity. Copyright 2001 National Science Council, ROC and S. Karger AG, Basel.

Effects of Cardiac Rehabilitation on Sexual Dysfunction of Post Myocardial Infarction Patients

Directory of Open Access Journals (Sweden)

Jamshid Najafian

2001-01-01

Full Text Available Objective: The common sexual complains in patients with coronary heart disease and post myocardial infarction are decrease in libido, impotence, and premature or delay ejaculation. Cardiac rehabilitation could decrease many of the psychological features of myocardial infarction and also increase exercise capacity of patients. Rehabilitation may also improve sexual disturbances in these patients directly or indirectly. This study is a clinical trial that evaluate the effect of rehabilitation on sexual problem of post MI patients. Materials & Methods: 60 patients took part in this study. All of them were men aged between 35 and 65. All patients had myocardial infarction one month ago. 30 patients were referred for cardiac rehabilitation (Case, and 30 people were patients who were not recommended to take part in rehabilitation because their physician did not believe on rehabilitation. Questioner for anxiety, depression, impotency, libido and premature ejaculation were evaluated by before and after study period. The cardiac rehabilitation composed of 24 sessions. Each session consisted of one hour of aerobic exercise (10 min warm up, 10 min cool down and 40 min isotonic exercise. Results: After cardiac rehabilitation the scores for anxiety, depression, premature ejaculation and impotency were decreased and the scores of libido were increased. In both case and control groups, the changes were significant by paired t test P<0.05. The differences between case and control were significant for depression, libido and impotency by independent t test. Conclusion: Cardiac rehabilitation could improve sexual problems in post myocardial infarction patients directly and indirectly by effect on psychological characteristics.

Regulatory effects of phospholamban on cardiac sarcoplasmic reticulum function

International Nuclear Information System (INIS)

Kim, Hae Won.

1989-01-01

In this thesis, the author reports the effect of phospholamban on: (a) Ca 2+ release by cardiac SR and (b) the Ca 2+ -ATPase activity in a purified reconstituted system. Phosphorylation of phospholamban by Ca 2+ · calmodulin-dependent protein kinase had no appreciable effect on the initial rates of Ca 2+ release from cardiac SR vesicles loaded under passive conditions and on the apparent 45 Ca 2+ - 40 Ca 2+ exchange from cardiac SR vesicles loaded under active conditions. us, it appears that Ca 2+ · calmodulin-dependent phosphorylation of phospholamban is not involved in the regulation of Ca 2+ release and 45 Ca 2+-40 Ca 2+ exchange. To determine the molecular mechanism by which phospholamban regulates the Ca 2+ pump, a reconstituted system was developed, using a freeze-thaw sonication procedure. The Ca 2+ -ATPase was purified by a method which yields an active enzyme preparation essentially free of phospholamban. The best rates of Ca 2+ uptake were obtained when cholate and phosphatidylcholine (PC) were used at a ratio of cholate/PC/Ca 2 + -ATPase of 2/80/1. The maximal rates of Ca 2+ Uptake were 700 nmol/min/mg reconstituted vesicles compared to 800 nmol/min/mg SR vesicles. The EC 50 values for Ca 2+ were 0.05 μM for both Ca 2+ uptake and Ca 2+ -ATPase activity in the reconstituted vesicles compared to 0.63 μM Ca 2+ in native SR vesicles. To determine the effect of phospholamban on the Ca + -ATPase activity in the reconstituted vesicles, purified phospholamban was added to the cholate/Ca 2+ -ATPase mixture prior to combining it with liposomes

Midodrine improves orgasm in spinal cord-injured men: the effects of autonomic stimulation.

Science.gov (United States)

Soler, Jean Marc; Previnaire, Jean Gabriel; Plante, Pierre; Denys, Pierre; Chartier-Kastler, Emmanuel

2008-12-01

Orgasm is less frequent in men with spinal cord injury (SCI) than in able-bodied subjects, and is poorly understood. To assess the effect of autonomic stimulation on orgasm in SCI men using midodrine, an alpha1-adrenergic agonist agent. Penile vibratory stimulation (PVS) was performed in 158 SCI men on midodrine as part of a treatment for anejaculation, after they failed a baseline PVS. A maximum of four trials were performed, weekly, with increasing doses of midodrine. The presence and type of ejaculation, orgasm experiences, and cardiovascular data were collected. Ejaculation either antegrade or retrograde was obtained in 102 SCI men (65%). Orgasm without ejaculation was reported by 14 patients (9%) on baseline PVS. Ninety-three patients (59%) experienced orgasm during PVS on midodrine. Orgasm was significantly related to the presence of ejaculation in 86 patients (84%), and more strikingly to antegrade ejaculation (pure or mixed with retrograde), i.e., in 98% of 70 patients. Orgasm was significantly more frequent in patients with upper motor neuron and incomplete lesions who present somatic responses during PVS. There was no effect of the presence of psychogenic erection. There was a significant increase in both systolic and diastolic blood pressure. Sixteen patients, mainly tetraplegics, developed intense autonomic dysreflexia (AD) that required an oral nicardipine chlorhydrate. Orgasm is the brain's cognitive interpretation of genital sensations and somatic responses, AD, and ejaculation. Intact sacral and T10-L2 cord segments are mandatory, allowing coordination between internal and external sphincters. Autonomic stimulation with midodrine enhances orgasm rate, mainly by creating antegrade ejaculation.

[Autonomic regulation at emotional stress under hypoxic conditions in the elderly with physiological and accelerated aging: effect of hypoxic training].

Science.gov (United States)

Os'mak, E D; Asanov, É O

2014-01-01

The effect of hypoxic training on autonomic regulation in psycho-emotional stress conditions in hypoxic conditions in older people with physiological (25 people) and accelerated (28 people) aging respiratory system. It is shown that hypoxic training leads to an increase in vagal activity indicators (HF) and reduced simpatovagal index (LF/HF), have a normalizing effect on the autonomic balance during stress loads in older people with different types of aging respiratory system.

Mathematical cardiac electrophysiology

CERN Document Server

Colli Franzone, Piero; Scacchi, Simone

2014-01-01

This book covers the main mathematical and numerical models in computational electrocardiology, ranging from microscopic membrane models of cardiac ionic channels to macroscopic bidomain, monodomain, eikonal models and cardiac source representations. These advanced multiscale and nonlinear models describe the cardiac bioelectrical activity from the cell level to the body surface and are employed in both the direct and inverse problems of electrocardiology. The book also covers advanced numerical techniques needed to efficiently carry out large-scale cardiac simulations, including time and space discretizations, decoupling and operator splitting techniques, parallel finite element solvers. These techniques are employed in 3D cardiac simulations illustrating the excitation mechanisms, the anisotropic effects on excitation and repolarization wavefronts, the morphology of electrograms in normal and pathological tissue and some reentry phenomena. The overall aim of the book is to present rigorously the mathematica...

Long-Term Dynamics of Autonomous Fractional Differential Equations

Science.gov (United States)

Liu, Tao; Xu, Wei; Xu, Yong; Han, Qun

This paper aims to investigate long-term dynamic behaviors of autonomous fractional differential equations with effective numerical method. The long-term dynamic behaviors predict where systems are heading after long-term evolution. We make some modification and transplant cell mapping methods to autonomous fractional differential equations. The mapping time duration of cell mapping is enlarged to deal with the long memory effect. Three illustrative examples, i.e. fractional Lotka-Volterra equation, fractional van der Pol oscillator and fractional Duffing equation, are studied with our revised generalized cell mapping method. We obtain long-term dynamics, such as attractors, basins of attraction, and saddles. Compared with some existing stability and numerical results, the validity of our method is verified. Furthermore, we find that the fractional order has its effect on the long-term dynamics of autonomous fractional differential equations.

Cardiac adverse effects of naloxone-precipitated morphine withdrawal on right ventricle: Role of corticotropin-releasing factor (CRF) 1 receptor

Energy Technology Data Exchange (ETDEWEB)

Navarro-Zaragoza, J.; Martínez-Laorden, E.; Mora, L.; Hidalgo, J.; Milanés, M.V.; Laorden, M.L., E-mail: laorden@um.es

2014-02-15

Opioid addiction is associated with cardiovascular disease. However, mechanisms linking opioid addiction and cardiovascular disease remain unclear. This study investigated the role of corticotropin-releasing factor (CRF) 1 receptor in mediating somatic signs and the behavioural states produced during withdrawal from morphine dependence. Furthermore, it studied the efficacy of CRF1 receptor antagonist, CP-154,526 to prevent the cardiac sympathetic activity induced by morphine withdrawal. In addition, tyrosine hydroxylase (TH) phosphorylation pathways were evaluated. Like stress, morphine withdrawal induced an increase in the hypothalamic–pituitary–adrenal (HPA) axis activity and an enhancement of noradrenaline (NA) turnover. Pre-treatment with CRF1 receptor antagonist significantly reduced morphine withdrawal-induced increases in plasma adrenocorticotropic hormone (ACTH) levels, NA turnover and TH phosphorylation at Ser31 in the right ventricle. In addition, CP-154,526 reduced the phosphorylation of extracellular signal-regulated kinase (ERK) after naloxone-precipitated morphine withdrawal. In addition, CP-154,526 attenuated the increases in body weight loss during morphine treatment and suppressed some of morphine withdrawal signs. Altogether, these results support the idea that cardiac sympathetic pathways are activated in response to naloxone-precipitated morphine withdrawal suggesting that treatment with a CRF1 receptor antagonist before morphine withdrawal would prevent the development of stress-induced behavioural and autonomic dysfunction in opioid addicts. - Highlights: • Morphine withdrawal caused an increase in myocardial sympathetic activity. • ERK regulates TH phosphorylation after naloxone-induced morphine withdrawal. • CRF1R is involved in cardiac adaptive changes during morphine dependence.

Cardiac adverse effects of naloxone-precipitated morphine withdrawal on right ventricle: Role of corticotropin-releasing factor (CRF) 1 receptor

International Nuclear Information System (INIS)

Navarro-Zaragoza, J.; Martínez-Laorden, E.; Mora, L.; Hidalgo, J.; Milanés, M.V.; Laorden, M.L.

2014-01-01

Opioid addiction is associated with cardiovascular disease. However, mechanisms linking opioid addiction and cardiovascular disease remain unclear. This study investigated the role of corticotropin-releasing factor (CRF) 1 receptor in mediating somatic signs and the behavioural states produced during withdrawal from morphine dependence. Furthermore, it studied the efficacy of CRF1 receptor antagonist, CP-154,526 to prevent the cardiac sympathetic activity induced by morphine withdrawal. In addition, tyrosine hydroxylase (TH) phosphorylation pathways were evaluated. Like stress, morphine withdrawal induced an increase in the hypothalamic–pituitary–adrenal (HPA) axis activity and an enhancement of noradrenaline (NA) turnover. Pre-treatment with CRF1 receptor antagonist significantly reduced morphine withdrawal-induced increases in plasma adrenocorticotropic hormone (ACTH) levels, NA turnover and TH phosphorylation at Ser31 in the right ventricle. In addition, CP-154,526 reduced the phosphorylation of extracellular signal-regulated kinase (ERK) after naloxone-precipitated morphine withdrawal. In addition, CP-154,526 attenuated the increases in body weight loss during morphine treatment and suppressed some of morphine withdrawal signs. Altogether, these results support the idea that cardiac sympathetic pathways are activated in response to naloxone-precipitated morphine withdrawal suggesting that treatment with a CRF1 receptor antagonist before morphine withdrawal would prevent the development of stress-induced behavioural and autonomic dysfunction in opioid addicts. - Highlights: • Morphine withdrawal caused an increase in myocardial sympathetic activity. • ERK regulates TH phosphorylation after naloxone-induced morphine withdrawal. • CRF1R is involved in cardiac adaptive changes during morphine dependence

Radioiodine therapy of functional autonomy using the functional autonomous volume

International Nuclear Information System (INIS)

Seeger, T.; Emrich, D.; Sandrock, D.

1995-01-01

In order to determine the effective radiation dose to be delivered by 131 I in functional autonomy we have used the functional autonomous volume calculated from the global 99m Tc thyroid uptake under exogenous or endogenous suppression before and 3 to 7 months after treatment. The radiation dose to the autonomous volume was calculated retrospectively in 131 patients with unifocal, multifocal and disseminated autonomy (75 hyperthyroid, 56 euthyroid) who received 131 I treatment of 200-300 Gy to the total volume of the gland. It could be shown that at least 350 Gy to the autonomous volume are required to reach the desired effect of treatment which was dependent only on the radiation dose delivered to the functional autonomous volume. (orig.) [de

Autonomic nervous system function in chronic exogenous subclinical thyrotoxicosis and the effect of restoring euthyroidism.

Science.gov (United States)

Eustatia-Rutten, Carmen F A; Corssmit, Eleonora P M; Heemstra, Karen A; Smit, Johannes W A; Schoemaker, Rik C; Romijn, Johannes A; Burggraaf, Jacobus

2008-07-01

Knowledge on the relationship between the autonomic nervous system and subclinical hyperthyroidism is mainly based upon cross-sectional studies in heterogeneous patient populations, and the effect of restoration to euthyroidism in subclinical hyperthyroidism has not been studied. We investigated the long-term effects of exogenous subclinical hyperthyroidism on the autonomic nervous system and the potential effects of restoration of euthyroidism. This was a prospective single-blinded, placebo-controlled, randomized trial. The study was performed at a university hospital. A total of 25 patients who were on more than 10-yr TSH suppressive therapy after thyroidectomy was examined. Patients were studied at baseline and subsequently randomized to a 6-month thyroid hormone substitution regimen to obtain either euthyroidism or maintenance of the subclinical hyperthyroid state. Urinary excretion of catecholamines and heart rate variability were measured. Baseline data of the subclinical hyperthyroidism patients were compared with data obtained in patients with hyperthyroidism and controls. Urinary excretion of norepinephrine and vanillylmandelic acid was higher in the subclinical hyperthyroidism patients compared with controls and lower compared with patients with overt hyperthyroidism. Heart rate variability was lower in patients with hyperthyroidism, intermediate in subclinical hyperthyroidism patients, and highest in the healthy controls. No differences were observed after restoration of euthyroidism. Long-term exogenous subclinical hyperthyroidism has effects on the autonomic nervous system measured by heart rate variability and urinary catecholamine excretion. No differences were observed after restoration to euthyroidism. This may indicate the occurrence of irreversible changes or adaptation during long-term exposure to excess thyroid hormone that is not remedied by 6-month euthyroidism.

Behavioral and biological effects of autonomous versus scheduled mission management in simulated space-dwelling groups

Science.gov (United States)

Roma, Peter G.; Hursh, Steven R.; Hienz, Robert D.; Emurian, Henry H.; Gasior, Eric D.; Brinson, Zabecca S.; Brady, Joseph V.

2011-05-01

Logistical constraints during long-duration space expeditions will limit the ability of Earth-based mission control personnel to manage their astronaut crews and will thus increase the prevalence of autonomous operations. Despite this inevitability, little research exists regarding crew performance and psychosocial adaptation under such autonomous conditions. To this end, a newly-initiated study on crew management systems was conducted to assess crew performance effectiveness under rigid schedule-based management of crew activities by Mission Control versus more flexible, autonomous management of activities by the crews themselves. Nine volunteers formed three long-term crews and were extensively trained in a simulated planetary geological exploration task over the course of several months. Each crew then embarked on two separate 3-4 h missions in a counterbalanced sequence: Scheduled, in which the crews were directed by Mission Control according to a strict topographic and temporal region-searching sequence, and Autonomous, in which the well-trained crews received equivalent baseline support from Mission Control but were free to explore the planetary surface as they saw fit. Under the autonomous missions, performance in all three crews improved (more high-valued geologic samples were retrieved), subjective self-reports of negative emotional states decreased, unstructured debriefing logs contained fewer references to negative emotions and greater use of socially-referent language, and salivary cortisol output across the missions was attenuated. The present study provides evidence that crew autonomy may improve performance and help sustain if not enhance psychosocial adaptation and biobehavioral health. These controlled experimental data contribute to an emerging empirical database on crew autonomy which the international astronautics community may build upon for future research and ultimately draw upon when designing and managing missions.

Effects of benazepril on cardiac fibrosis in STZ-induced diabetic rats.

Science.gov (United States)

Li, Qian; Wang, Yi; Sun, Shu-zhen; Tian, Yong-jie; Liu, Ming-hua

2010-08-01

The present study was designed to explore the roles of MMP-2/TIMP-2 in cardiac fibrosis and to study the effects of benazepril, an angiotensin-converting enzyme inhibitor (ACEI) on cardiac remodelling in streptozotocin(STZ)-induced diabetic rats. Male Wistar rats were randomly divided into three groups: a normal control group (NC), a diabetes mellitus-untreated group (DM) and a diabetes mellitus benazepril-treated group (DB). Diabetes mellitus was induced in the DM and DB groups by intraperitoneal injection of streptozotocin (60 mg/kg). DB rats were treated with benazepril 10 mg/kg/day for 12 weeks by remedial perfusing of the stomach. In the DM group, compared with the NC group, the gene and protein expression of MMP-2 decreased while the TIMP-2 gene and protein expression increased in heart tissues, along with a markedly cardiac collagen deposition.All the above changes were attenuated by benazepril treatment in the DB group. The imbalance of MMP-2 and TIMP-2 expressions in heart tissues might participate in interstitial fibrosis in diabetic myocardiopathy. Benazepril may ameliorate cardiac fibrosis partly by regulating the MMP-2/TIMP-2 system.

Effects of the july 1997 floods in the Czech Republic on cardiac mortality.

Science.gov (United States)

Obrová, Jana; Sovová, Eliška; Ivanová, Kateřina; Táborský, Miloš; Loyka, Svatopluk

2014-12-01

An excess of deaths from cardiac causes are reported after many natural disasters. Despite the fact that floods are the most common and most destructive natural disaster worldwide, little is known about their effect on human health. We analyzed the influence of the greatest floods in the Czech Republic on cardiac mortality in the affected area. This was a retrospective case-control study. We analyzed persons whose autopsies proved they had died of cardiac causes during the month of the flood, 2 months before the flood, 1 month after the flood, and during the same period in the 3 previous years. A total of 207 of 985 autopsy reports met the criteria for inclusion in the study. There were no significant differences in the proportions of men and women (P=0.819) or in age (P=0.577). During the month of the flood, an increase in cardiac mortality was observed; however, the increase was not statistically significant (P=0.088). According to our findings, the 1997 Central European flood did not significantly affect cardiac mortality.

Nesfatin-1 activates cardiac vagal neurons of nucleus ambiguus and elicits bradycardia in conscious rats.

Science.gov (United States)

Brailoiu, G Cristina; Deliu, Elena; Tica, Andrei A; Rabinowitz, Joseph E; Tilley, Douglas G; Benamar, Khalid; Koch, Walter J; Brailoiu, Eugen

2013-09-01

Nesfatin-1, a peptide whose receptor is yet to be identified, has been involved in the modulation of feeding, stress, and metabolic responses. More recently, increasing evidence supports a modulatory role for nesfatin-1 in autonomic and cardiovascular activity. This study was undertaken to test if the expression of nesfatin-1 in the nucleus ambiguus, a key site for parasympathetic cardiac control, may be correlated with a functional role. As we have previously demonstrated that nesfatin-1 elicits Ca²⁺ signaling in hypothalamic neurons, we first assessed the effect of this peptide on cytosolic Ca²⁺ in cardiac pre-ganglionic neurons of nucleus ambiguus. We provide evidence that nesfatin-1 increases cytosolic Ca²⁺ concentration via a Gi/o-coupled mechanism. The nesfatin-1-induced Ca²⁺ rise is critically dependent on Ca²⁺ influx via P/Q-type voltage-activated Ca²⁺ channels. Repeated administration of nesfatin-1 leads to tachyphylaxis. Furthermore, nesfatin-1 produces a dose-dependent depolarization of cardiac vagal neurons via a Gi/o-coupled mechanism. In vivo studies, using telemetric and tail-cuff monitoring of heart rate and blood pressure, indicate that microinjection of nesfatin-1 into the nucleus ambiguus produces bradycardia not accompanied by a change in blood pressure in conscious rats. Taken together, our results identify for the first time that nesfatin-1 decreases heart rate by activating cardiac vagal neurons of nucleus ambiguus. Our results indicate that nesfatin-1, one of the most potent feeding peptides, increases cytosolic Ca²⁺ by promoting Ca²⁺ influx via P/Q channels and depolarizes nucleus ambiguus neurons; both effects are Gi/o-mediated. In vivo studies indicate that microinjection of nesfatin-1 into nucleus ambiguus produces bradycardia in conscious rats. This is the first report that nesfatin-1 increases the parasympathetic cardiac tone. © 2013 International Society for Neurochemistry.

On the health paradox of occupational and leisure-time physical activity using objective measurements: Effects on autonomic imbalance.

Directory of Open Access Journals (Sweden)

David M Hallman

Full Text Available Leisure-time physical activity (LTPA has considerable benefits for cardiovascular health and longevity, while occupational physical activity (OPA is associated with an elevated cardiovascular risk. This "health paradox" may be explained by different effects on the autonomic nervous system from OPA and LTPA. Thus, we aimed to investigate whether objectively measured OPA and LTPA are differentially associated with autonomic regulation among workers.The study comprised 514 blue-collar workers from the Danish cohort DPHACTO. Physical activity (i.e. walking, climbing stairs, running and cycling was assessed objectively using accelerometers worn on the thigh, hip and trunk over multiple working days. During this period, a heart rate monitor was used to sample heart period intervals from the ECG signal. Heart rate and heart rate variability (HRV indices were analyzed during nocturnal sleep as markers of autonomic regulation. Multiple regression analysis was used to determine the main effects of OPA and LTPA and their interaction on heart rate and HRV, adjusting for multiple confounders.Statistically significant interaction was found between OPA and LTPA on heart rate (adjusted p<0.0001 and HRV indices in time (rMSSD, adjusted p = 0.004 and frequency-domains (HF, adjusted p = 0.022; LF, adjusted p = 0.033. The beneficial effect of LTPA on nocturnal heart rate and HRV clearly diminished with higher levels of OPA, and high levels of both OPA and LTPA had a detrimental effect.We found contrasting associations for objectively measured OPA and LTPA with heart rate and HRV during sleep. Differential effects of OPA and LTPA on autonomic regulation may contribute to the physical activity health paradox.

Intermittent Exposure to Social Defeat and Open-field Test in Rats : Acute and Long-term Effects on ECG, Body Temperature and Physical Activity

NARCIS (Netherlands)

Sgoifo, Andrea; Pozzato, Chiara; Meerlo, Peter; Costoli, Tania; Manghi, Massimo; Stilli, Donatella; Olivetti, Giorgio; Musso, Ezio

2002-01-01

This study investigated the effects of exposure to an intermittent homotypic stressor on: (i) habituation of acute autonomic responsivity (i.e. cardiac sympathovagal balance and susceptibility to arrhythmias), and (ii) circadian rhythmicity of heart rate, body temperature, and physical activity.

Funções autonômica cardíaca e mecânica ventricular na cardiopatia chagásica crônica assintomática Cardiac autonomic and ventricular mechanical functions in asymptomatic chronic chagasic cardiomyopathy

Directory of Open Access Journals (Sweden)

Daniel França Vasconcelos

2012-02-01

Full Text Available FUNDAMENTO: A associação das funções autonômica cardíaca e ventricular sisto-diastólica variavelmente alteradas ainda é controversa e pouco explorada na cardiopatia chagásica crônica. OBJETIVO: Avaliar em que extensão as funções autonômica cardíaca e mecânica ventricular estão alteradas e se ambas estão relacionadas na cardiopatia chagásica assintomática. MÉTODOS: EM 13 cardiopatas chagásicos assintomáticos e 15 indivíduos normais (grupo controle, foram avaliadas e correlacionadas a modulação autonômica da variabilidade da frequência cardíaca durante cinco minutos, nos domínios temporal e espectral, nas posições supina e ortostática, e a função ventricular com base em variáveis morfofuncionais Doppler ecocardiográficas. A análise estatística empregou o teste de Mann-Whitney e a correlação de Spearman. RESULTADOS: Em ambas as posições, os índices temporais (p = 0,0004-0,01 e as áreas espectrais total (p = 0,0007-0,005 e absoluta, de baixa e alta frequências (p = 0,0001-0,002, mostraram-se menores no grupo chagásico. O balanço vagossimpático mostrou-se semelhante em ambas as posturas (p = 0,43-0,89. As variáveis ecocardiográficas não diferiram entre os grupos (p = 0,13-0,82, exceto o diâmetro sistólico final do ventrículo esquerdo que se mostrou maior (p = 0,04, correlacionando-se diretamente com os reduzidos índices da modulação autonômica global (p = 0,01-0,04 e parassimpática (p = 0,002-0,01, nos pacientes chagásicos, em posição ortostática. CONCLUSÃO: AS DEpressões simpática e parassimpática com balanço preservado associaram-se apenas a um indicador de disfunção ventricular. Isso sugere que a disfunção autonômica cardíaca pode preceder e ser independentemente mais severa que a disfunção ventricular, não havendo associação causal entre ambos os distúrbios na cardiopatia chagásica crônica.BACKGROUND: The association of variably altered cardiac autonomic and

Trastuzumab-associated cardiac adverse effects in the herceptin adjuvant trial

NARCIS (Netherlands)

Suter, Thomas M.; Procter, Marion; van Veldhuisen, Dirk J.; Muscholl, Michael; Bergh, Jonas; Carlomagno, Chiara; Perren, Timothy; Passalacqua, Rodolfo; Bighin, Claudia; Klijn, Jan G. M.; Ageev, Fail T.; Hitre, Erika; Groetz, Juergen; Iwata, Hiroji; Knap, Malgorzata; Gnant, Michael; Muehlbauer, Susanne; Spence, Alison; Gelber, Richard D.; Piccart-Gebhart, Martine J.

2007-01-01

Purpose The purpose of this analysis was to investigate trastuzumab- associated cardiac adverse effects in breast cancer patients after completion of ( neo) adjuvant chemotherapy with or without radiotherapy. Patients and Methods The Herceptin Adjuvant ( HERA) trial is a three- group, multicenter,

Longitudinal Control for Mengshi Autonomous Vehicle via Cloud Model

Science.gov (United States)

Gao, H. B.; Zhang, X. Y.; Li, D. Y.; Liu, Y. C.

2018-03-01

Dynamic robustness and stability control is a requirement for self-driving of autonomous vehicle. Longitudinal control method of autonomous is a key technique which has drawn the attention of industry and academe. In this paper, we present a longitudinal control algorithm based on cloud model for Mengshi autonomous vehicle to ensure the dynamic stability and tracking performance of Mengshi autonomous vehicle. An experiments is applied to test the implementation of the longitudinal control algorithm. Empirical results show that if the longitudinal control algorithm based Gauss cloud model are applied to calculate the acceleration, and the vehicles drive at different speeds, a stable longitudinal control effect is achieved.

Muscle metaboreflex and autonomic regulation of heart rate in humans

DEFF Research Database (Denmark)

Fisher, James P; Adlan, Ahmed M; Shantsila, Alena

2013-01-01

) conditions, but attenuated with β-adrenergic blockade (0.2 ± 1 beats min(-1); P > 0.05 vs. rest). Thus muscle metaboreflex activation-mediated increases in HR are principally attributable to increased cardiac sympathetic activity, and only following exercise with a large muscle mass (PEI following leg......We elucidated the autonomic mechanisms whereby heart rate (HR) is regulated by the muscle metaboreflex. Eight male participants (22 ± 3 years) performed three exercise protocols: (1) enhanced metaboreflex activation with partial flow restriction (bi-lateral thigh cuff inflation) during leg cycling...... exercise, (2) isolated muscle metaboreflex activation (post-exercise ischaemia; PEI) following leg cycling exercise, (3) isometric handgrip followed by PEI. Trials were undertaken under control (no drug), β1-adrenergic blockade (metoprolol) and parasympathetic blockade (glycopyrrolate) conditions. HR...

Testing for autonomic neuropathy

DEFF Research Database (Denmark)

Hilsted, J

1984-01-01