NASA Technical Reports Server (NTRS)
Taylor, J. A.; Myers, C. W.; Halliwill, J. R.; Seidel, H.; Eckberg, D. L.
2001-01-01
Clinicians and experimentalists routinely estimate vagal-cardiac nerve traffic from respiratory sinus arrhythmia. However, evidence suggests that sympathetic mechanisms may also modulate respiratory sinus arrhythmia. Our study examined modulation of respiratory sinus arrhythmia by sympathetic outflow. We measured R-R interval spectral power in 10 volunteers that breathed sequentially at 13 frequencies, from 15 to 3 breaths/min, before and after beta-adrenergic blockade. We fitted changes of respiratory frequency R-R interval spectral power with a damped oscillator model: frequency-dependent oscillations with a resonant frequency, generated by driving forces and modified by damping influences. beta-Adrenergic blockade enhanced respiratory sinus arrhythmia at all frequencies (at some, fourfold). The damped oscillator model fit experimental data well (39 of 40 ramps; r = 0.86 +/- 0.02). beta-Adrenergic blockade increased respiratory sinus arrhythmia by amplifying respiration-related driving forces (P < 0.05), without altering resonant frequency or damping influences. Both spectral power data and the damped oscillator model indicate that cardiac sympathetic outflow markedly reduces heart period oscillations at all frequencies. This challenges the notion that respiratory sinus arrhythmia is mediated simply by vagal-cardiac nerve activity. These results have important implications for clinical and experimental estimation of human vagal cardiac tone.
Respiratory sinus arrhythmia is a limited measure of cardiac parasympathetic control in man.
Kollai, M; Mizsei, G
1990-01-01
1. Respiratory modulation of cardiac parasympathetic activity and the relationship between respiratory sinus arrhythmia and parasympathetic control has been studied in twenty-nine conscious, healthy young adult subjects. 2. Changes in heart period in propranolol-treated subjects were taken as the measure of changes in cardiac parasympathetic activity; respiratory sinus arrhythmia was quantified as the difference between maximum and minimum heart periods in a given respiratory cycle; cardiac parasympathetic control was defined as the change in heart period after administration of a full dose of atropine. 3. During normal quiet breathing the inspiratory level of cardiac parasympathetic activity was not reduced to zero. The expiratory level was influenced by excitatory inputs whose activation was related to respiratory cycle length. 4. Slow breathing was associated with augmented sinus arrhythmia, but in different individuals the influence on minimum and maximum heart periods varied so that mean heart period was increased in some subjects but decreased in others. This occurred both in control conditions and after administration of a full dose of propranolol. 5. During normal breathing the correlation across subjects between respiratory sinus arrhythmia and parasympathetic control, although significant, was not close (r = 0.61). The relationship was not affected by beta-adrenergic blockade (r = 0.63). The strength of the correlation improved when multiple regression of respiratory sinus arrhythmia was performed on three variables: parasympathetic control, respiratory cycle length and tidal volume (R = 0.93). 6. It is concluded that in conscious human subjects the respiratory modulation of cardiac parasympathetic activity is different from that observed in the anaesthetized dog, and that variations in the amplitude of respiratory sinus arrhythmia do not necessarily reflect proportional changes in cardiac parasympathetic control. PMID:2391653
Sundararajan, Premkumar; Sangaralingam, Thangavelu
2016-01-01
Introduction The presentation of symptoms of paediatric arrhythmias vary depending on the age and underlying heart disease. Physical examination of children with important arrhythmias may be entirely normal. Aim Aim is to study the characteristics of cardiac arrhythmias in paediatric patients in a tertiary paediatric care centre in Chennai, India. Materials and Methods The participants (n=60) were from birth to 12 years of age. Patients with sinus arrhythmias, sinus tachycardia and sinus bradycardia were excluded. Proportions of various parameters of interest like clinical features, age and sex distribution and underlying heart disease of children presenting with cardiac arrhythmias were arrived. Statistical analysis was performed using SPSS version 16.0. Results Ventricular ectopics were the most common type of arrhythmias observed in the present study followed by Sinus Node Dysfunction (SND). The most common type of SND was sino atrial arrest. Supra ventricular tachycardia was the most frequently sustained tachyarrhythmia in the present study. An increased association of WPW (Wolf Parkinson White Syndrome) with specific congenital cardiac defects was noted. Conclusion Cardiac arrhythmias in children can present at anytime from fetal life to adolescence and their recognition requires high index of suspicion. While majority of children with arrhythmias have structurally normal heart, they are frequently encountered in children with underlying heart disease. Treatment of paediatric arrhythmias should be guided by the severity of the patient, the structure and function of the heart. PMID:28208963
Autonomic reactivity during viewing of an unpleasant film.
Baldaro, B; Mazzetti, M; Codispoti, M; Tuozzi, G; Bolzani, R; Trombini, G
2001-12-01
The effect of an aversive, high-arousing film on heart rate, respiratory sinus arrhythmia, and electrogastrographic activity (EGG) was investigated. Previous studies have indicated a larger heart-rate deceleration for visual stimuli depicting surgery or blood compared to neutral content, and this phenomenon is similar to the bradycardia observed in animals in response to fear. The heart-rate deceleration is clearly parasympathetically driven, and it is considered a general index of attention. An accurate index of cardiac vagal tone can be obtained by means of quantification of the amplitude of respiratory sinus arrhythmia. The relationship between cardiac vagal tone and EGG is complex, but animal research has shown that suppressing vagal activity dampens gastric motility. We have investigated whether a movie depicting surgery is associated with greater heart-rate deceleration, larger increase in respiratory sinus arrhythmia, and greater increase in EGG activity compared to a neutral movie. In addition, if both respiratory sinus arrhythmia and EGG are indices of vagal tone, a positive correlation between these physiological responses was expected. Analysis indicated an effect of the surgery movie on heart rate and respiratory sinus arrhythmia, but not on EGG activity. Moreover, the expected correlation was not found. Implications for future studies are discussed.
Klotho protein lowered in senile patients with brady sinus arrhythmia.
Wang, Ying; Yang, Wei; Zheng, Ernv; Zhang, Wei; Su, Xianming
2015-01-01
To explore the correlationship between brady sinus arrhythmia and the levels of serum klotho protein in aged. 104 patients over 75 years old with brady sinus arrhythmia (experiment group) were enrolled, including 34 cases of sinus arrest, 43 cases of sinus bradycardia and 25 cases of atrioventricular block. 109 patients over 75 years old without brady sinus arrhymia were chosen as control group. All subjects were monitored by Holter. The levels of serum klotho protein were detected and compared among three groups. The correlation between the frequency of sinus arrest and the levels of serum klotho protein was analyzed simultaneously. The levels of serum klotho protein in experiment group were lower than that in control group (P<0.01); the sinus arrest frequency was negatively correlated with the levels of serum klotho protien. The levels of serum klotho protein in patients with sinus arrest were lower than that with sinus bradycardia and atrioventricularblock (P<0.05). But there was no significant difference between sinus bradycardia group and atrioventricular block group. The levels of serum klotho protein may reflect the function of sinoatrial node and could be used as an index to estimate the function of sinoatrial node.
Klotho protein lowered in senile patients with brady sinus arrhythmia
Wang, Ying; Yang, Wei; Zheng, Ernv; Zhang, Wei; Su, Xianming
2015-01-01
Objective: To explore the correlationship between brady sinus arrhythmia and the levels of serum klotho protein in aged. Methods: 104 patients over 75 years old with brady sinus arrhythmia (experiment group) were enrolled, including 34 cases of sinus arrest, 43 cases of sinus bradycardia and 25 cases of atrioventricular block. 109 patients over 75 years old without brady sinus arrhymia were chosen as control group. All subjects were monitored by Holter. The levels of serum klotho protein were detected and compared among three groups. The correlation between the frequency of sinus arrest and the levels of serum klotho protein was analyzed simultaneously. Results: The levels of serum klotho protein in experiment group were lower than that in control group (P<0.01); the sinus arrest frequency was negatively correlated with the levels of serum klotho protien. The levels of serum klotho protein in patients with sinus arrest were lower than that with sinus bradycardia and atrioventricularblock (P<0.05). But there was no significant difference between sinus bradycardia group and atrioventricular block group. Conclusion: The levels of serum klotho protein may reflect the function of sinoatrial node and could be used as an index to estimate the function of sinoatrial node. PMID:26550342
... rhythm problems (arrhythmias) in which the heart's natural pacemaker (sinus node) doesn't work properly. The sinus ... people with sick sinus syndrome eventually need a pacemaker to keep the heart in a regular rhythm. ...
ERIC Educational Resources Information Center
Neuhaus, Emily; Bernier, Raphael; Beauchaine, Theodore P.
2014-01-01
Theoretical and empirical models describe respiratory sinus arrhythmia (RSA) as a peripheral biomarker of emotion regulation and social competence. Recent findings also link RSA to individual differences in social functioning within autism spectrum disorder (ASD). However, associations between RSA and symptoms of internalizing/externalizing…
Development of the cardiac pacemaker
Liang, Xingqun; Evans, Sylvia M.
2017-01-01
The sinoatrial node (SAN) is the dominant pacemaker of the heart. Abnormalities in SAN formation and function can cause sinus arrhythmia, including sick sinus syndrome and sudden death. A better understanding of genes and signaling pathways that regulate SAN development and function is essential to develop more effective treatment to sinus arrhythmia, including biological pacemakers. In this review, we briefly summarize the key processes of SAN morphogenesis during development, and focus on the transcriptional network that drives SAN development. PMID:27770149
Brief Report: Emotion Regulation and Respiratory Sinus Arrhythmia in Autism Spectrum Disorder
ERIC Educational Resources Information Center
Guy, Lisa; Souders, Margaret; Bradstreet, Lauren; DeLussey, Christine; Herrington, John D.
2014-01-01
Emotion regulation (ER) may be an important transdiagnostic factor for understanding mental and behavioral health given its association with several psychiatric disorders, including autism spectrum disorder (ASD). However, there is limited research on ER in ASD, particularly using biomarkers such as respiratory sinus arrhythmia (RSA). The aim of…
ERIC Educational Resources Information Center
Wetter, Emily K.; El-Sheikh, Mona
2012-01-01
Background: We assessed trajectories of children's internalizing symptoms as predicted by interactions among maternal internalizing symptoms, respiratory sinus arrhythmia (RSA) and child sex. Method: An ethnically and socioeconomically diverse sample of children (n = 251) participated during three study waves. Children's mean ages were 8.23 years…
ERIC Educational Resources Information Center
Eisenberg, Nancy; Sulik, Michael J.; Spinrad, Tracy L.; Edwards, Alison; Eggum, Natalie D.; Liew, Jeffrey; Sallquist, Julie; Popp, Tierney K.; Smith, Cynthia L.; Hart, Daniel
2012-01-01
The purpose of the current study was to predict the development of aggressive behavior from young children's respiratory sinus arrhythmia (RSA) and environmental quality. In a longitudinal sample of 213 children, baseline RSA, RSA suppression in response to a film of crying babies, and a composite measure of environmental quality (incorporating…
Bourassa, Kyle J; Hasselmo, Karen; Sbarra, David A
2016-08-01
Divorce is a stressor associated with long-term health risk, though the mechanisms of this effect are poorly understood. Cardiovascular reactivity is one biological pathway implicated as a predictor of poor long-term health after divorce. A sample of recently separated and divorced adults (N = 138) was assessed over an average of 7.5 months to explore whether individual differences in heart rate variability-assessed by respiratory sinus arrhythmia-operate in combination with subjective reports of separation-related distress to predict prospective changes in cardiovascular reactivity, as indexed by blood pressure reactivity. Participants with low resting respiratory sinus arrhythmia at baseline showed no association between divorce-related distress and later blood pressure reactivity, whereas participants with high respiratory sinus arrhythmia showed a positive association. In addition, within-person variation in respiratory sinus arrhythmia and between-persons variation in separation-related distress interacted to predict blood pressure reactivity at each laboratory visit. Individual differences in heart rate variability and subjective distress operate together to predict cardiovascular reactivity and may explain some of the long-term health risk associated with divorce. © The Author(s) 2016.
Simulation of Cardiac Arrhythmias Using a 2D Heterogeneous Whole Heart Model
Balakrishnan, Minimol; Chakravarthy, V. Srinivasa; Guhathakurta, Soma
2015-01-01
Simulation studies of cardiac arrhythmias at the whole heart level with electrocardiogram (ECG) gives an understanding of how the underlying cell and tissue level changes manifest as rhythm disturbances in the ECG. We present a 2D whole heart model (WHM2D) which can accommodate variations at the cellular level and can generate the ECG waveform. It is shown that, by varying cellular-level parameters like the gap junction conductance (GJC), excitability, action potential duration (APD) and frequency of oscillations of the auto-rhythmic cell in WHM2D a large variety of cardiac arrhythmias can be generated including sinus tachycardia, sinus bradycardia, sinus arrhythmia, sinus pause, junctional rhythm, Wolf Parkinson White syndrome and all types of AV conduction blocks. WHM2D includes key components of the electrical conduction system of the heart like the SA (Sino atrial) node cells, fast conducting intranodal pathways, slow conducting atriovenctricular (AV) node, bundle of His cells, Purkinje network, atrial, and ventricular myocardial cells. SA nodal cells, AV nodal cells, bundle of His cells, and Purkinje cells are represented by the Fitzhugh-Nagumo (FN) model which is a reduced model of the Hodgkin-Huxley neuron model. The atrial and ventricular myocardial cells are modeled by the Aliev-Panfilov (AP) two-variable model proposed for cardiac excitation. WHM2D can prove to be a valuable clinical tool for understanding cardiac arrhythmias. PMID:26733873
ERIC Educational Resources Information Center
Jones, Robin M.; Walden, Tedra A.; Conture, Edward G.; Erdemir, Aysu; Lambert, Warren E.; Porges, Stephen W.
2017-01-01
Purpose: This study sought to determine whether respiratory sinus arrhythmia (RSA) and executive functions are associated with stuttered speech disfluencies of young children who do (CWS) and do not stutter (CWNS). Method: Thirty-six young CWS and 36 CWNS were exposed to neutral, negative, and positive emotion-inducing video clips, followed by…
New Methods for the Analysis of Heartbeat Behavior in Risk Stratification
Glass, Leon; Lerma, Claudia; Shrier, Alvin
2011-01-01
Developing better methods for risk stratification for tachyarrhythmic sudden cardiac remains a major challenge for physicians and scientists. Since the transition from sinus rhythm to ventricular tachycardia/fibrillation happens by different mechanisms in different people, it is unrealistic to think that a single measure will be adequate to provide a good index for risk stratification. We analyze the dynamical properties of ventricular premature complexes over 24 h in an effort to understand the underlying mechanisms of ventricular arrhythmias and to better understand the arrhythmias that occur in individual patients. Two dimensional density plots, called heartprints, correlate characteristic features of the dynamics of premature ventricular complexes and the sinus rate. Heartprints show distinctive characteristics in individual patients. Based on a better understanding of the natures of transitions from sinus rhythm to sudden cardiac and the mechanisms of arrhythmia prior to cardiac arrest, it should be possible to develop better methods for risk stratification. PMID:22144963
1978-06-01
responses (AER) with a photo-optico-electronic method. Habituation was obtained by binaural stimulation with monotonously repeated clicki of a constant...Bonsper, D. E. The effect of increased information processing on sinus arrhythmia and heart beat Monti-y,7UalTfrniaITNaval Postgraduate School...September 1970. (NTIS No. ’’A’’A f śS4) This experiment investigated the eflt of increased information processing on heart beat and sinus arrhythmia. A
Bidirectional Cardio-Respiratory Interactions in Heart Failure.
Radovanović, Nikola N; Pavlović, Siniša U; Milašinović, Goran; Kirćanski, Bratislav; Platiša, Mirjana M
2018-01-01
We investigated cardio-respiratory coupling in patients with heart failure by quantification of bidirectional interactions between cardiac (RR intervals) and respiratory signals with complementary measures of time series analysis. Heart failure patients were divided into three groups of twenty, age and gender matched, subjects: with sinus rhythm (HF-Sin), with sinus rhythm and ventricular extrasystoles (HF-VES), and with permanent atrial fibrillation (HF-AF). We included patients with indication for implantation of implantable cardioverter defibrillator or cardiac resynchronization therapy device. ECG and respiratory signals were simultaneously acquired during 20 min in supine position at spontaneous breathing frequency in 20 healthy control subjects and in patients before device implantation. We used coherence, Granger causality and cross-sample entropy analysis as complementary measures of bidirectional interactions between RR intervals and respiratory rhythm. In heart failure patients with arrhythmias (HF-VES and HF-AF) there is no coherence between signals ( p < 0.01), while in HF-Sin it is reduced ( p < 0.05), compared with control subjects. In all heart failure groups causality between signals is diminished, but with significantly stronger causality of RR signal in respiratory signal in HF-VES. Cross-sample entropy analysis revealed the strongest synchrony between respiratory and RR signal in HF-VES group. Beside respiratory sinus arrhythmia there is another type of cardio-respiratory interaction based on the synchrony between cardiac and respiratory rhythm. Both of them are altered in heart failure patients. Respiratory sinus arrhythmia is reduced in HF-Sin patients and vanished in heart failure patients with arrhythmias. Contrary, in HF-Sin and HF-VES groups, synchrony increased, probably as consequence of some dominant neural compensatory mechanisms. The coupling of cardiac and respiratory rhythm in heart failure patients varies depending on the presence of atrial/ventricular arrhythmias and it could be revealed by complementary methods of time series analysis.
Respiratory sinus arrhythmia in Chagas disease.
Neves, Victor Ribeiro; Peltola, Mirja; Huikuri, Heikki; Rocha, Manoel Otávio da Costa; Ribeiro, Antonio Luiz
2014-10-01
We applied the respiratory sinus arrhythmia (RSA) quantification algorithm to 24-hour ECG recordings of Chagas disease (ChD) patients with (G1, n=148) and without left ventricular dysfunction (LVD) (G2, n=33), and in control subjects (G0, n=28). Both ChD groups displayed a reduced RSA index; G1=299 (144-812); G2=335 (162-667), p=0.011, which was correlated with vagal indexes of heart rate variability analysis. RSA index is a marker of vagal modulation in ChD patients. Copyright © 2014 Elsevier B.V. All rights reserved.
Arrhythmias Following Comprehensive Stage II Surgical Palliation in Single Ventricle Patients.
Wilhelm, Carolyn M; Paulus, Diane; Cua, Clifford L; Kertesz, Naomi J; Cheatham, John P; Galantowicz, Mark; Fernandez, Richard P
2016-03-01
Post-operative arrhythmias are common in pediatric patients following cardiac surgery. Following hybrid palliation in single ventricle patients, a comprehensive stage II palliation is performed. The incidence of arrhythmias in patients following comprehensive stage II palliation is unknown. The purpose of this study is to determine the incidence of arrhythmias following comprehensive stage II palliation. A single-center retrospective chart review was performed on all single ventricle patients undergoing a comprehensive stage II palliation from January 2010 to May 2014. Pre-operative, operative, and post-operative data were collected. A clinically significant arrhythmia was defined as an arrhythmia which led to cardiopulmonary resuscitation or required treatment with either pacing or antiarrhythmic medication. Statistical analysis was performed with Wilcoxon rank-sum test and Fisher's exact test with p < 0.05 significant. Forty-eight single ventricle patients were reviewed (32 hypoplastic left heart syndrome, 16 other single ventricle variants). Age at surgery was 185 ± 56 days. Cardiopulmonary bypass time was 259 ± 45 min. Average vasoactive-inotropic score was 5.97 ± 7.58. Six patients (12.5 %) had clinically significant arrhythmias: four sinus bradycardia, one 2:1 atrioventricular block, and one slow junctional rhythm. No tachyarrhythmias were documented for this patient population. Presence of arrhythmia was associated with elevated lactate (p = 0.04) and cardiac arrest (p = 0.002). Following comprehensive stage II palliation, single ventricle patients are at low risk for development of tachyarrhythmias. The most frequent arrhythmia seen in these patients was sinus bradycardia associated with respiratory compromise.
Contijoch, Francisco; Witschey, Walter R T; Rogers, Kelly; Rears, Hannah; Hansen, Michael; Yushkevich, Paul; Gorman, Joseph; Gorman, Robert C; Han, Yuchi
2015-05-21
Data obtained during arrhythmia is retained in real-time cardiovascular magnetic resonance (rt-CMR), but there is limited and inconsistent evidence to show that rt-CMR can accurately assess beat-to-beat variation in left ventricular (LV) function or during an arrhythmia. Multi-slice, short axis cine and real-time golden-angle radial CMR data was collected in 22 clinical patients (18 in sinus rhythm and 4 patients with arrhythmia). A user-initialized active contour segmentation (ACS) software was validated via comparison to manual segmentation on clinically accepted software. For each image in the 2D acquisitions, slice volume was calculated and global LV volumes were estimated via summation across the LV using multiple slices. Real-time imaging data was reconstructed using different image exposure times and frame rates to evaluate the effect of temporal resolution on measured function in each slice via ACS. Finally, global volumetric function of ectopic and non-ectopic beats was measured using ACS in patients with arrhythmias. ACS provides global LV volume measurements that are not significantly different from manual quantification of retrospectively gated cine images in sinus rhythm patients. With an exposure time of 95.2 ms and a frame rate of > 89 frames per second, golden-angle real-time imaging accurately captures hemodynamic function over a range of patient heart rates. In four patients with frequent ectopic contractions, initial quantification of the impact of ectopic beats on hemodynamic function was demonstrated. User-initialized active contours and golden-angle real-time radial CMR can be used to determine time-varying LV function in patients. These methods will be very useful for the assessment of LV function in patients with frequent arrhythmias.
Cardiac regulation in the socially monogamous prairie vole
Grippo, Angela J.; Lamb, Damon G.; Carter, C. Sue; Porges, Stephen W.
2007-01-01
Social experiences, both positive and negative, may influence cardiovascular regulation. Prairie voles (Microtus ochrogaster) are socially monogamous rodents that form social bonds similar to those seen in primates, and this species may provide a useful model for investigating neural and social regulation of cardiac function. Cardiac regulation has not been studied previously in the prairie vole. Radiotelemetry transmitters were implanted into adult female prairie voles under anesthesia, and electrocardiographic parameters were recorded. Autonomic blockade was performed using atenolol (8 mg/kg ip) and atropine methyl nitrate (4 mg/kg ip). Several variables were evaluated, including heart rate (HR), HR variability and the amplitude of respiratory sinus arrhythmia. Sympathetic blockade significantly reduced HR. Parasympathetic blockade significantly increased HR, and reduced HR variability and the amplitude of respiratory sinus arrhythmia. Combined autonomic blockade significantly increased HR, and reduced HR variability and respiratory sinus arrhythmia amplitude. The data indicate that autonomic function in prairie voles shares similarities with primates, with a predominant vagal influence on cardiac regulation. The current results provide a foundation for studying neural and social regulation of cardiac function during different behavioral states in this socially monogamous rodent model. PMID:17107695
Dijkman, B; Wellens, H J
2000-12-01
Performance of dual chamber implantable cardioverter defibrillator (ICD) systems has been judged based on functioning of the ventricular tachycardia:supraventricular tachycardia (VT:SVT) discrimination criteria and DDD pacing. The purpose of this study was to evaluate the use of dual chamber diagnostics to improve the electrical and antiarrhythmic therapy of ventricular arrhythmias. Information about atrial and ventricular rhythm in relation to ventricular arrhythmia occurrence and therapy was evaluated in 724 spontaneous arrhythmia episodes detected and treated by three types of dual chamber ICDs in 41 patients with structural heart disease. Device programming was based on clinically documented and induced ventricular arrhythmias. In ambulatory patients, sinus tachycardia preceded ventricular arrhythmias more often than in the hospital during exercise testing. The incidence of these VTs could be reduced by increasing the dose of a beta-blocking agent in only two patients. In five patients in whom sinus tachycardia developed after onset of hemodynamic stable VT, propranolol was more effective than Class III antiarrhythmics combined with another beta-blocking agent with regard to the incidence of VT and pace termination. In all but three cases, atrial arrhythmias were present for a longer time before the onset of ventricular arrhythmias. During atrial arrhythmias, fast ventricular rates before the onset of ventricular rate were observed more often than RR irregularities and short-long RR sequences. Dual chamber diagnostics allowed proper interpretation of detection and therapy outcome in patients with different types of ventricular arrhythmia. The advantages of the dual chamber ICD system go further than avoiding the shortcomings of the single chamber system. Information from the atrial chamber allows better device programming and individualization of drug therapy for ventricular arrhythmia.
Autonomic Nervous System Reactivity: Children With and Without Sickle Cell Disease
Treadwell, Marsha J.; Alkon, Abbey; Styles, Lori; Boyce, W. Thomas
2011-01-01
Background Previous studies of healthy children have demonstrated a link between autonomic nervous system (ANS) reactivity and health outcomes, but there is limited research on whether ANS reactivity is similar for children with chronic conditions. Objective To determine if ANS reactivity differs for children with sickle cell disease (SCD) compared to a community sample of children without SCD. Method In two cross-sectional, descriptive studies, 32 public school children without chronic health problems were compared with 33 children with SCD. The children were 5-8 years old and they completed standardized protocols measuring ANS responses (respiratory sinus arrhythmia and pre-ejection period) during rest and challenge conditions in social, cognitive, sensory, and emotion domains. Reactivity was calculated as the difference between challenge response minus rest for each domain and overall. Results There were differences in the distributions of the samples in parent education and child age, so these variables were adjusted for in subsequent analyses. The community sample showed parasympathetic withdrawal (low respiratory sinus arrhythmia scores) and greater parasympathetic reactivity (low respiratory sinus arrhythmia difference scores and percentage of negative scores) compared with the children with SCD in the social (p < .05) and sensory domains (p < .05). The children with SCD showed greater sympathetic reactivity (low preejection period difference scores) compared with the community children in the cognitive domain (p < .05) and a greater percentage of children with SCD versus the community children showed negative pre-ejection period difference scores (sympathetic reactivity) in the social domain (p < .05). The community sample, but not the children with SCD, showed changes in respiratory sinus arrhythmia across domains (p < .05). Discussion Children with SCD may display a different pattern of ANS responses to laboratory challenges compared with children without SCD from the same community. PMID:21532352
Kumar, Saurabh; Sutherland, Fiona; Wheeler, Miriam; Heck, Patrick M; Lee, Geoffrey; Teh, Andrew W; Garg, Manohar L; Morgan, John G; Sparks, Paul B
2011-05-01
Atrial mechanical stunning is a form of tachycardia-mediated atrial cardiomyopathy that manifests after reversion of persistent atrial arrhythmias to sinus rhythm. This study sought to examine whether chronic omega-3 polyunsaturated fatty acid supplementation with fish oils can reverse atrial mechanical stunning. Patients undergoing reversion of persistent atrial fibrillation (AF) or atrial flutter (AFL) to sinus rhythm were randomized to a control group (n = 26) or an omega-3 group (n = 23). The latter were prescribed 6 g/day of fish oil for ≥1 month prior to the procedure. Parameters of left atrial appendage function were compared immediately before and immediately after reversion. After fish oil intake for a mean of 70 days, the following were noted favoring the omega-3 group among both AF and AFL patients: (1) 2-fold higher serum omega-3 levels (P < .001), (2) less mean decrease in emptying velocity (e.g., AF: 8% vs. 32%, P = .02), (3) less mean decrease in appendage emptying fraction (e.g., AFL: 7% vs. 60%, P = .002), (4) lower incidence of new or increased spontaneous echocardiographic contrast (e.g., AF: 11% vs. 62.5%, P = .003), and (5) lower incidence of atrial mechanical stunning (e.g., AFL: 20% vs. 100%, P = .001). Omega-3 intake conferred protection against stunning in a multivariable analysis (odds ratio 0.18, P = .02). Chronic fish oil ingestion in humans attenuates atrial mechanical stunning after reversion of atrial arrhythmias to sinus rhythm. This suggests that fish oils may target or even reverse underlying cellular and/or structural remodeling that occurs in response to persistent atrial arrhythmias. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.
Spectral analysis of sinus arrhythmia - A measure of mental effort
NASA Technical Reports Server (NTRS)
Vicente, Kim J.; Craig Thornton, D.; Moray, Neville
1987-01-01
The validity of the spectral analysis of sinus arrhythmia as a measure of mental effort was investigated using a computer simulation of a hovercraft piloted along a river as the experimental task. Strong correlation was observed between the subjective effort-ratings and the heart-rate variability (HRV) power spectrum between 0.06 and 0.14 Hz. Significant correlations were observed not only between subjects but, more importantly, within subjects as well, indicating that the spectral analysis of HRV is an accurate measure of the amount of effort being invested by a subject. Results also indicate that the intensity of effort invested by subjects cannot be inferred from the objective ratings of task difficulty or from performance.
Chen, Minglong; Gu, Kai; Yang, Bing; Chen, Hongwu; Ju, Weizhu; Zhang, Fengxiang; Yang, Gang; Li, Mingfang; Lu, Xinzheng; Cao, Kejiang; Ouyang, Feifan
2014-12-01
Accelerated idioventricular rhythm (AIVR) or ventricular tachycardia (VT) originating from the right bundle branch (RBB) is rare and published clinical data on such arrhythmia are scarce. In this study, we will describe the clinical manifestations, diagnosis, and management of a cohort of patients with this novel arrhythmia. Eight patients (5 men; median age, 25 years) with RBB-AIVR/VT were consecutively enrolled in the study. Pharmacological testing, exercise treadmill testing, electrophysiological study, and catheter ablation were performed in the study patients, and ECG features were characterized. All RBB-AIVR/VTs were of typical left bundle-branch block morphology with atrioventricular dissociation. The arrhythmias, which demonstrated chronotropic variability, were often isorhythmic with sinus rhythm and were accelerated by physical exercise, stress, and intravenous isoprenaline infusion. The rate of RBB-AIVR/VT varied from 45 to 200 beats per minute. Two patients experienced syncope, and 3 had impaired left ventricular function. Metoprolol was proven to be the most effective drug to decelerate the arrhythmia rate and relieve symptoms. Electrophysiology study was performed in 5 patients and the earliest activation with a sharp RBB potential was localized in the mid or distal RBB area. Catheter ablation terminated the arrhythmia with subsequent RBB block morphology during sinus rhythm. During follow-up, patients' symptoms were controlled with normalization of left ventricular function either on metoprolol or by catheter ablation. RBB-AIVR/VT is an unusual type of ventricular arrhythmia. It can result in significant symptoms and depressed ventricular function and can be successfully treated with catheter ablation. © 2014 American Heart Association, Inc.
Contributions of tidal lung inflation to human R-R interval and arterial pressure fluctuations
NASA Technical Reports Server (NTRS)
Koh, J.; Brown, T. E.; Beightol, L. A.; Eckberg, D. L.
1998-01-01
We studied the effects of mechanical lung inflation on respiratory frequency R-R interval and arterial pressure fluctuations in nine healthy young adults undergoing elective orthopedic surgery. We conducted this research to define the contribution of pulmonary and thoracic stretch receptor input to respiratory sinus arrhythmia. We compared fast Fourier transform spectral power during three modes of ventilation: (1) spontaneous, frequency-controlled (0.25 Hz) breathing, (2) intermittent positive pressure ventilation (0.25 Hz, with a tidal volume of 8 ml/kg) and (3) high frequency jet ventilation (5.0 Hz, 2.5 kg/cm2), after sedation and vecuronium paralysis. Mean R-R intervals, arterial pressures and arterial blood gas levels were comparable during all three breathing conditions. Respiratory frequency systolic pressure spectral power was comparable during spontaneous breathing and conventional mechanical ventilation, but was significantly reduced during high frequency jet ventilation (P < 0.05). Respiratory frequency R-R interval spectral power (used as an index of respiratory sinus arrhythmia) declined dramatically with sedation and muscle paralysis (P < 0.05), but was greater during conventional mechanical, than high frequency jet ventilation (P < 0.05). These results suggest that although phasic inputs from pulmonary and thoracic stretch receptors make a statistically significant contribution to respiratory sinus arrhythmia, that contribution is small.
Wariishi, Seiichiro; Yamashita, Koichi; Nishimori, Hideaki; Fukutomi, Takashi; Yamamoto, Masaki; Radhakrishnan, Geethalakshmi; Sasaguri, Shiro
2009-11-01
The purpose of this study was to investigate the efficacy of landiolol hydrochloride, a short-acting beta(1) blocker, by initiating its administration at a low dose (5 microg kg(-1) min(-1)) in patients with postoperative supraventricular arrhythmia. The efficacy of landiolol was evaluated in 38 patients who, after developing postoperative atrial flutter or fibrillation, with sinus tachycardia and two patients who had a history of paroxysmal atrial fibrillation with frequent atrial extrasystole. The heart rate and blood pressure before and 2 h after the administration of landiolol were compared. A return to the sinus rhythm from supraventricular arrhythmia was noted in 89%. The heart rate was reduced from 137+/-26 bpm (before landiolol administration) to 93+/-18 bpm (2 h after the start of the medication, P<0.01). As an agent to correct an arrhythmic condition, landiolol successfully raised the systolic blood pressure from 108+/-24 mmHg (before medication) to 120+/-19 mmHg (2 h after the medication was started, P<0.05). Continuous intravenous infusion of landiolol at a low dose was found to be effective for postoperative supraventricular arrhythmia.
Validation of electromechanical wave imaging in a canine model during pacing and sinus rhythm.
Grondin, Julien; Costet, Alexandre; Bunting, Ethan; Gambhir, Alok; Garan, Hasan; Wan, Elaine; Konofagou, Elisa E
2016-11-01
Accurate determination of regional areas of arrhythmic triggers is of key interest to diagnose arrhythmias and optimize their treatment. Electromechanical wave imaging (EWI) is an ultrasound technique that can image the transient deformation in the myocardium after electrical activation and therefore has the potential to detect and characterize location of triggers of arrhythmias. The objectives of this study were to investigate the relationship between the electromechanical and the electrical activation of the left ventricular (LV) endocardial surface during epicardial and endocardial pacing and during sinus rhythm as well as to map the distribution of electromechanical delays. In this study, 6 canines were investigated. Two external electrodes were sutured onto the epicardial surface of the LV. A 64-electrode basket catheter was inserted through the apex of the LV. Ultrasound channel data were acquired at 2000 frames/s during epicardial and endocardial pacing and during sinus rhythm. Electromechanical and electrical activation maps were synchronously obtained from the ultrasound data and the basket catheter, respectively. The mean correlation coefficient between electromechanical and electrical activation was 0.81 for epicardial anterior pacing, 0.79 for epicardial lateral pacing, 0.69 for endocardial pacing, and 0.56 for sinus rhythm. The electromechanical activation sequence determined by EWI follows the electrical activation sequence and more specifically in the case of pacing. This finding is of key interest in the role that EWI can play in the detection of the anatomical source of arrhythmias and the planning of pacing therapies such as cardiovascular resynchronization therapy. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Validation of Electromechanical Wave Imaging in a canine model during pacing and sinus rhythm
Grondin, Julien; Costet, Alexandre; Bunting, Ethan; Gambhir, Alok; Garan, Hasan; Wan, Elaine; Konofagou, Elisa E.
2016-01-01
Background Accurate determination of regional areas of arrhythmic triggers is of key interest to diagnose arrhythmias and optimize their treatment. Electromechanical wave imaging (EWI) is an ultrasound technique that can image the transient deformation in the myocardium following electrical activation and therefore has the potential to detect and characterize location of triggers of arrhythmias. Objectives The objectives of this study are to investigate the relationship between electromechanical and electrical activation of the left-ventricular (LV) endocardial surface during epicardial and endocardial pacing as well as during sinus rhythm and also to investigate the distribution of electromechanical delays. Methods In this study, six canines were investigated. Two external electrodes were sutured onto the epicardial surface of the left ventricle (LV). A 64-electrode basket catheter was inserted through the apex of the LV. Ultrasound channel data were acquired at 2000 frames/s during epicardial and endocardial pacing as well as during sinus rhythm. Electromechanical and electrical activation maps were synchronously obtained from the ultrasound data and the basket catheter respectively. Results The mean correlation coefficient between electromechanical and electrical activation was R=0.81 for epicardial anterior pacing, R=0.79 for epicardial lateral pacing, R=0.69 for endocardial pacing and R=0.56 for sinus rhythm. Conclusions The electromechanical activation sequence determined by EWI follows the electrical activation sequence and more specifically in the case of pacing. This finding is of key interest in the role that EWI can play in the detection of the anatomical source of arrhythmias and the planning of pacing therapies such as cardiovascular resynchronization therapy. PMID:27498277
Noll, Laura K; Clark, Caron A C; Skowron, Elizabeth A
2015-11-01
Despite burgeoning evidence linking early exposure to child maltreatment (CM) to deficits in self-regulation, the pathways to strong regulatory development in these children are not well understood, and significant heterogeneity is observed in their outcomes. Experiences of autonomy may play a key role in transmitting self-regulatory capacity across generations and help explain individual differences in maltreatment outcomes. In this study, we investigated multigenerational associations between Generation 1 (G1)-Generation 2 (G2) mothers' early experience of warmth and autonomy in relation to their own mothers and their Generation 3 (G3) children's autonomic physiological regulation in CM (n = 85) and non-CM (n = 128) families. We found that G2 mothers who recalled greater autonomy in their childhood relationship with their G1 mothers had preschool-age G3 children with higher respiratory sinus arrhythmia at baseline when alone while engaged in individual challenge tasks, during social exchanges with their mother in joint challenge tasks, and during the portions of the strange situation procedure when the mother was present. Although no clear mediators of this association emerged, multigenerational links among G1-G2 relations, maternal representations of her child, child behavior, and child respiratory sinus arrhythmia differed by maltreatment status, thus possibly representing important targets for future research and intervention.
NOLL, LAURA K.; CLARK, CARON A. C.; SKOWRON, ELIZABETH A.
2017-01-01
Despite burgeoning evidence linking early exposure to child maltreatment (CM) to deficits in self-regulation, the pathways to strong regulatory development in these children are not well understood, and significant heterogeneity is observed in their outcomes. Experiences of autonomy may play a key role in transmitting self-regulatory capacity across generations and help explain individual differences in maltreatment outcomes. In this study, we investigated multigenerational associations between Generation 1 (G1)–Generation 2 (G2) mothers’ early experience of warmth and autonomy in relation to their own mothers and their Generation 3 (G3) children’s autonomic physiological regulation in CM (n = 85) and non-CM (n = 128) families. We found that G2 mothers who recalled greater autonomy in their childhood relationship with their G1 mothers had preschool-age G3 children with higher respiratory sinus arrhythmia at baseline when alone while engaged in individual challenge tasks, during social exchanges with their mother in joint challenge tasks, and during the portions of the strange situation procedure when the mother was present. Although no clear mediators of this association emerged, multigenerational links among G1–G2 relations, maternal representations of her child, child behavior, and child respiratory sinus arrhythmia differed by maltreatment status, thus possibly representing important targets for future research and intervention. PMID:26535936
Fundamental relations between short-term RR interval and arterial pressure oscillations in humans
NASA Technical Reports Server (NTRS)
Taylor, J. A.; Eckberg, D. L.
1996-01-01
BACKGROUND: One of the principal explanations for respiratory sinus arrhythmia is that it reflects arterial baroreflex buffering of respiration-induced arterial pressure fluctuations. If this explanation is correct, then elimination of RR interval fluctuations should increase respiratory arterial pressure fluctuations. METHODS AND RESULTS: We measured RR interval and arterial pressure fluctuations during normal sinus rhythm and fixed-rate atrial pacing at 17.2+/-1.8 (SEM) beats per minute greater than the sinus rate in 16 healthy men and 4 healthy women, 20 to 34 years of age. Measurements were made during controlled-frequency breathing (15 breaths per minute or 0.25 Hz) with subjects in the supine and 40 degree head-up tilt positions. We characterized RR interval and arterial pressure variabilities in low-frequency (0.05 to 0.15 Hz) and respiratory-frequency (0.20 to 0.30 Hz) ranges with fast Fourier transform power spectra and used cross-spectral analysis to determine the phase relation between the two signals. As expected, cardiac pacing eliminated beat-to-beat RR interval variability. Against expectations, however, cardiac pacing in the supine position significantly reduced arterial pressure oscillations in the respiratory frequency (systolic, 6.8+/-1.8 to 2.9 +/-0.6 mm Hg2/Hz, P=.017). In contrast, cardiac pacing in the 40 degree tilt position increased arterial pressure variability (systolic, 8.0+/-1.8 to 10.8 +/-2.6, P=.027). Cross-spectral analysis showed that 40 degree tilt shifted the phase relation between systolic pressure and RR interval at the respiratory frequency from positive to negative (9 +/-7 degrees versus -17+/-11 degrees, P=.04); that is, in the supine position, RR interval changes appeared to lead arterial pressure changes, and in the upright position, RR interval changes appeared to follow arterial pressure changes. CONCLUSIONS: These results demonstrate that respiratory sinus arrhythmia can actually contribute to respiratory arterial pressure fluctuations. Therefore, respiratory sinus arrhythmia does not represent simple baroreflex buffering of arterial pressure.
Resting respiratory sinus arrhythmia is associated with tonic positive emotionality.
Oveis, Christopher; Cohen, Adam B; Gruber, June; Shiota, Michelle N; Haidt, Jonathan; Keltner, Dacher
2009-04-01
Resting respiratory sinus arrhythmia (RSAREST) indexes important aspects of individual differences in emotionality. In the present investigation, the authors address whether RSAREST is associated with tonic positive or negative emotionality, and whether RSAREST relates to phasic emotional responding to discrete positive emotion-eliciting stimuli. Across an 8-month, multiassessment study of first-year university students (n = 80), individual differences in RSAREST were associated with positive but not negative tonic emotionality, assessed at the level of personality traits, long-term moods, the disposition toward optimism, and baseline reports of current emotional states. RSAREST was not related to increased positive emotion, or stimulus-specific emotion, in response to compassion-, awe-, or pride-inducing stimuli. These findings suggest that resting RSA indexes aspects of a person's tonic positive emotionality. (c) 2009 APA, all rights reserved.
Pürerfellner, Helmut; Sanders, Prashanthan; Sarkar, Shantanu; Reisfeld, Erin; Reiland, Jerry; Koehler, Jodi; Pokushalov, Evgeny; Urban, Luboš; Dekker, Lukas R C
2017-10-03
Intermittent change in p-wave discernibility during periods of ectopy and sinus arrhythmia is a cause of inappropriate atrial fibrillation (AF) detection in insertable cardiac monitors (ICM). To address this, we developed and validated an enhanced AF detection algorithm. Atrial fibrillation detection in Reveal LINQ ICM uses patterns of incoherence in RR intervals and absence of P-wave evidence over a 2-min period. The enhanced algorithm includes P-wave evidence during RR irregularity as evidence of sinus arrhythmia or ectopy to adaptively optimize sensitivity for AF detection. The algorithm was developed and validated using Holter data from the XPECT and LINQ Usability studies which collected surface electrocardiogram (ECG) and continuous ICM ECG over a 24-48 h period. The algorithm detections were compared with Holter annotations, performed by multiple reviewers, to compute episode and duration detection performance. The validation dataset comprised of 3187 h of valid Holter and LINQ recordings from 138 patients, with true AF in 37 patients yielding 108 true AF episodes ≥2-min and 449 h of AF. The enhanced algorithm reduced inappropriately detected episodes by 49% and duration by 66% with <1% loss in true episodes or duration. The algorithm correctly identified 98.9% of total AF duration and 99.8% of total sinus or non-AF rhythm duration. The algorithm detected 97.2% (99.7% per-patient average) of all AF episodes ≥2-min, and 84.9% (95.3% per-patient average) of detected episodes involved AF. An enhancement that adapts sensitivity for AF detection reduced inappropriately detected episodes and duration with minimal reduction in sensitivity. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Cardiology
NASA Technical Reports Server (NTRS)
Ulyaninskiy, L. S.; Urmancheyeva, T. G.; Stepanyan, Y. P.; Fufacheva, A. A.; Gritsak, A. V.; Kuznetsova, B. A.; Kvitka, A. A.
1982-01-01
Experimental emotional stress which can produce various disorders of cardiac rhythm: sinus tachycardia, atrial fibrillation, ventricular, extrasystoles and paroxysmal ventricular tachysystoles was studied. In these conditions the adrenalin content in the blood and myocardium is increased 3 to 4 times. It is found that moderate motor activity leads to a relative decrease of adrenalin in the myocardium and arrest of cardiac arrhythmias.
Sanroman-Junquera, Margarita; Mora-Jimenez, Inmaculada; Garcia-Alberola, Arcadio; Caamano, Antonio J; Trenor, Beatriz; Rojo-Alvarez, Jose L
2018-04-01
Spatial and temporal processing of intracardiac electrograms provides relevant information to support the arrhythmia ablation during electrophysiological studies. Current cardiac navigation systems (CNS) and electrocardiographic imaging (ECGI) build detailed 3-D electroanatomical maps (EAM), which represent the spatial anatomical distribution of bioelectrical features, such as activation time or voltage. We present a principled methodology for spectral analysis of both EAM geometry and bioelectrical feature in CNS or ECGI, including their spectral representation, cutoff frequency, or spatial sampling rate (SSR). Existing manifold harmonic techniques for spectral mesh analysis are adapted to account for a fourth dimension, corresponding to the EAM bioelectrical feature. Appropriate scaling is required to address different magnitudes and units. With our approach, simulated and real EAM showed strong SSR dependence on both the arrhythmia mechanism and the cardiac anatomical shape. For instance, high frequencies increased significantly the SSR because of the "early-meets-late" in flutter EAM, compared with the sinus rhythm. Besides, higher frequency components were obtained for the left atrium (more complex anatomy) than for the right atrium in sinus rhythm. The proposed manifold harmonics methodology opens the field toward new signal processing tools for principled EAM spatiofeature analysis in CNS and ECGI, and to an improved knowledge on arrhythmia mechanisms.
Ramírez, A; Gil, M; Martínez Ríos, M A; Cárdenas, M; Pliego, J; Zamora, C; Mata, L A
1982-01-01
Four hundred patients with atrial septal defect treated surgically were reviewed. Thirty five (8.7%) developed arrhytmias post-surgery which persisted for over a year. Sinus bradycardia was found in 10 patients, nodal rhythm in 21, and atrial fibrilation and flutter in 4 patients. Thirty five per cent of the patients with late arrhythmias developed related symptomatology. In 14 patients the function of the sinus node was studied with electrical stimulation of the atrium and with His registry. The interatrial conduction time, AV node and His Purkinje were analized employing various stimulation frequencies. All the cases studied had normal intra-atrial conduction; the response of the atrio-ventricular node to increasing frequencies was normal, an the intraventricular conduction remained constant. In 8 patients (52%), alterations of the sinus node were found; these consisted of prolonged post-stimulation pauses, Wenckebach's type sinoatrial block and suppression of sinus automatism employing vagal procedures or through electrical stimulation. A patient with severe bradycardia detected by dynamic electrocardiography had to be treated with a permanent pacemaker. We confirm that these arrhytmias are not produced by lesions of the internodal tracts, and that an alteration of the sinus node is frequent without a concomitant lesion of the intraventricular pathway. The lesion to the nutrient artery could be due to trauma and/or surgically induced. The response to anticholinergic drugs was good. Prolonged observation of these patients could increase the morbility of these arrythmias and raise doubts of the surgical indications in cases with moderate hemodynamic repercussion.
Laske, Timothy G; Harlow, Henry J; Garshelis, David L; Iaizzo, Paul A
2010-10-01
American black bears survive winter months without food and water while in a mildly hypothermic, hypometabolic, and inactive state, yet they appear to be able to return to near-normal systemic function within minutes of arousal. This study's goal was to characterize the cardiovascular performance of overwintering black bears and elicit the underlying mechanisms enabling survival. Mid-winter cardiac electrophysiology was assessed in four wild black bears using implanted data recorders. Paired data from early and late winter were collected from 37 wild bears, which were anesthetized and temporarily removed from their dens to record cardiac electrophysiological parameters (12-lead electrocardiograms) and cardiac dimensional changes (echocardiography). Left ventricular thickness, primary cardiac electrophysiological parameters, and cardiovascular response to threats ("fight or flight" response) were preserved throughout winter. Dramatic respiratory sinus arrhythmias were recorded (cardiac cycle length variations up to 865%) with long sinus pauses between breaths (up to 13 s). The accelerated heart rate during breathing efficiently transports oxygen, with the heart "resting" between breaths to minimize energy usage. This adaptive cardiac physiology may have broad implications for human medicine.
Vezzosi, T; Buralli, C; Marchesotti, F; Porporato, F; Tognetti, R; Zini, E; Domenech, O
2016-10-01
The diagnostic accuracy of a smartphone electrocardiograph (ECG) in evaluating heart rhythm and ECG measurements was evaluated in 166 dogs. A standard 6-lead ECG was acquired for 1 min in each dog. A smartphone ECG tracing was simultaneously recorded using a single-lead bipolar ECG recorder. All ECGs were reviewed by one blinded operator, who judged if tracings were acceptable for interpretation and assigned an electrocardiographic diagnosis. Agreement between smartphone and standard ECG in the interpretation of tracings was evaluated. Sensitivity and specificity for the detection of arrhythmia were calculated for the smartphone ECG. Smartphone ECG tracings were interpretable in 162/166 (97.6%) tracings. A perfect agreement between the smartphone and standard ECG was found in detecting bradycardia, tachycardia, ectopic beats and atrioventricular blocks. A very good agreement was found in detecting sinus rhythm versus non-sinus rhythm (100% sensitivity and 97.9% specificity). The smartphone ECG provided tracings that were adequate for analysis in most dogs, with an accurate assessment of heart rate, rhythm and common arrhythmias. The smartphone ECG represents an additional tool in the diagnosis of arrhythmias in dogs, but is not a substitute for a 6-lead ECG. Arrhythmias identified by the smartphone ECG should be followed up with a standard ECG before making clinical decisions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Alamanni, Francesco; Veglia, Fabrizio; Galli, Claudia; Parolari, Alessandro; Zanobini, Marco
2015-01-01
The radiofrequency maze procedure achieves sinus rhythm in 45%–95% of patients treated for atrial fibrillation. This retrospective study evaluates mid-term results of the radiofrequency maze—performed concomitant to elective cardiac surgery—to determine sinus-rhythm predictive factors, and describes the evolution of patients' echocardiographic variables. From 2003 through 2011, 247 patients (mean age, 64 ± 9.5 yr) with structural heart disease (79.3% mitral disease) and atrial fibrillation underwent a concomitant radiofrequency modified maze procedure. Patients were monitored by 24-hour Holter at 3, 6, 12, and 24 months, then annually. Eighty-four mitral-valve patients underwent regular echocardiographic follow-up. Univariate and multivariate analysis for risk factors of maze failure were identified. The in-hospital mortality rate was 1.2%. During a median follow-up of 39.4 months, the late mortality rate was 3.6%, and pacemaker insertion was necessary in 26 patients (9.4%). Sinus rhythm was present in 63% of patients at the latest follow-up. Predictive factors for atrial fibrillation recurrence were arrhythmia duration (hazard ratio [HR]=1.296, P=0.045) and atrial fibrillation at hospital discharge (HR=2.03, P=0.019). The monopolar device favored maze success (HR=0.191, P <0.0001). Left atrial area and indexed left ventricular end-diastolic volume showed significant decrease both in sinus rhythm and atrial fibrillation patients. Early sinus rhythm conversion was associated with improved left ventricular ejection fraction. Concomitant radiofrequency maze procedure provided remarkable outcomes. Shorter preoperative atrial fibrillation duration, monopolar device use, and prompt treatment of arrhythmia recurrences increase the midterm success rate. Early sinus rhythm restoration seems to result in better left ventricular ejection fraction recovery. PMID:26413016
Simulation system of arrhythmia using ActiveX control.
Takeuchi, Akihiro; Hirose, Minoru; Hamada, Atsushi; Ikeda, Noriaki
2005-07-01
A simulation system for arrhythmias has been developed using Windows-based software technology, ActiveX control. The cardiac module consists of six cells, the sinus, atrium, AV node, ventricle, and ectopic foci. The physiological properties of the cells, the automaticity and conduction delay, were modelled, respectively, by the phase response curve and the excitability recovery curve. Cell functions were implemented in the ActiveX control and incorporated into the cardiac module. The system draws the ECG sequence as a ladder diagram in real time. The system interactively shows diverse arrhythmias for various user settings of the cell function and bidirectional conduction between the cells. Users are able to experiment virtually by setting up a so-called electrophysiological stimulation. This system is useful for learning and for teaching the interaction between the cells and arrhythmias.
Post Ross procedure aortic right sinus of Valsalva fistula to right ventricle.
Williams-Phillips, S
2011-12-01
Post Ross procedure complications have been limited predominantly to neoaortic valvular dilatation (10-30%) and insufficiency, right ventricular prosthetic deterioration or right ventricular pulmonary artery conduit obstruction. Arrhythmia has been documented to occur in a third of these patients. This is the first time that neoaortic right sinus of valsalva dissection and rupture to the right ventricle with a fistulous communication has occurred and been described, as far as the author is aware.
Beauchaine, Theodore P.
2015-01-01
In the past two decades, respiratory sinus arrhythmia (RSA)—an index of parasympathetic nervous system (PNS)-mediated cardiac control—has emerged as a reliable peripheral biomarker of emotion regulation (ER). Reduced RSA and excessive RSA reactivity (i.e., withdrawal) to emotional challenge are observed consistently among individuals with poor ER capabilities, including those with various forms of internalizing and externalizing psychopathology, and those with specific psychopathological syndromes, including anxiety, phobias, attention problems, autism, callousness, conduct disorder, depression, non-suicidal self-injury, panic disorder, and trait hostility. Emerging evidence suggests that low RSA and excessive RSA reactivity index poor ER because they are downstream peripheral markers of prefrontal cortex (PFC) dysfunction. Poorly modulated inhibitory efferent pathways from the medial PFC to the PNS result in reduced RSA and excessive RSA reactivity. According to this perspective, RSA is a non-invasive proxy for poor executive control over behavior, which characterizes most forms of psychopathology. PMID:25866835
Respiratory Sinus Arrhythmia, Shyness, and Effortful Control in Preschool-Age Children
Sulik, Michael J.; Eisenberg, Nancy; Silva, Kassondra M.; Spinrad, Tracy L.; Kupfer, Anne
2015-01-01
Resting respiratory sinus arrhythmia (RSA) and shyness were examined as predictors of effortful control (EC) in a sample of 101 preschool-age children. Resting RSA was calculated from respiration and heart rate data collected during a neutral film; shyness was measured using parents’, preschool teachers’, and classroom observers’ reports; and EC was measured using four laboratory tasks in addition to questionnaire measures. Principal components analysis was used to create composite measures of EC and shyness. The relation between RSA and EC was moderated by shyness, such that RSA was positively related to EC only for children high in shyness. This interaction suggests that emotional reactivity affects the degree to which RSA can be considered a correlate of EC. This study also draws attention to the need to consider the measurement context when assessing resting psychophysiology measures; shy individuals may not exhibit true baseline RSA responding in an unfamiliar laboratory setting. PMID:23127725
Cardiorespiratory interactions in patients with atrial flutter.
Masè, Michela; Disertori, Marcello; Ravelli, Flavia
2009-01-01
Respiratory sinus arrhythmia (RSA) is generally known as the autonomically mediated modulation of the sinus node pacemaker frequency in synchrony with respiration. Cardiorespiratory interactions have been largely investigated during sinus rhythm, whereas little is known about interactions during reentrant arrhythmias. In this study, cardiorespiratory interactions at the atrial and ventricular level were investigated during atrial flutter (AFL), a supraventricular arrhythmia based on a reentry, by using cross-spectral analysis and computer modeling. The coherence and phase between respiration and atrial (gamma(AA)(2), phi(AA)) and ventricular (gamma(RR)(2), phi(RR)) interval series were estimated in 20 patients with typical AFL (68.0 +/- 8.8 yr) and some degree of atrioventricular (AV) conduction block. In all patients, atrial intervals displayed oscillations strongly coupled and in phase with respiration (gamma(AA)(2)= 0.97 +/- 0.05, phi(AA) = 0.71 +/- 0.31 rad), corresponding to a paradoxical lengthening of intervals during inspiration. The modulation pattern was frequency independent, with in-phase oscillations and short time delays (0.40 +/- 0.15 s) for respiratory frequencies in the range 0.1-0.4 Hz. Ventricular patterns were affected by AV conduction type. In patients with fixed AV conduction, ventricular intervals displayed oscillations strongly coupled (gamma(RR)(2)= 0.97 +/- 0.03) and in phase with respiration (phi(RR) = 1.08 +/- 0.80 rad). Differently, in patients with variable AV conduction, respiratory oscillations were secondary to Wencheback rhythmicity, resulting in a decreased level of coupling (gamma(RR)(2)= 0.50 +/- 0.21). Simulations with a simplified model of AV conduction showed ventricular patterns to originate from the combination of a respiratory modulated atrial input with the functional properties of the AV node. The paradoxical frequency-independent modulation pattern of atrial interval, the short time delays, and the complexity of ventricular rhythm characterize respiratory arrhythmia during AFL and distinguish it from normal RSA. These peculiar features can be explained by assuming a direct mechanical action of respiration on AFL reentrant circuit.
Hinnant, J. Benjamin; EL-Sheikh, Mona
2013-01-01
We investigated the roles of sex and respiratory sinus arrhythmia (RSA), an index of autonomic parasympathetic nervous system activity, as predictors of codeveloping externalizing and internalizing symptoms in middle childhood. We expected that sex, baseline RSA (RSA-B), and RSA reactivity (RSA-R) to two types of tasks would interact to differentiate co-occurring trajectories of symptoms. We tested these hypotheses by combining longitudinal data from two independent samples (n = 390; 210 girls, 180 boys) with repeated measures at ages 8, 9, 10, and 11. RSA-R was measured in response to a socially stressful and frustrating stressor. Indicators of growth in externalizing and internalizing symptoms were derived from multiple domain growth models and used in person-centered growth mixture analyses. Three groups of externalizing and internalizing trajectories were found. Profile membership was predicted by several two-way interactions among sex, RSA-B, or RSA-R but was not predicted by three-way interactions. Children with low RSA-B and strong RSA withdrawal, girls with low RSA-B, and girls with strong RSA withdrawal were more likely to be on a developmental trajectory of low externalizing symptoms and moderately elevated internalizing symptoms. Membership in the high externalizing and high internalizing trajectory was predicted by weak RSA withdrawal for boys and strong RSA withdrawal for girls. The type of stressor task also played a role in predicting probability of profile membership. Results are discussed in the context of developmental psychobiology and implications for the codevelopment of psychopathology symptoms in childhood. PMID:23627954
[Shock shape representation of sinus heart rate based on cloud model].
Yin, Wenfeng; Zhao, Jie; Chen, Tiantian; Zhang, Junjian; Zhang, Chunyou; Li, Dapeng; An, Baijing
2014-04-01
The present paper is to analyze the trend of sinus heart rate RR interphase sequence after a single ventricular premature beat and to compare it with the two parameters, turbulence onset (TO) and turbulence slope (TS). Based on the acquisition of sinus rhythm concussion sample, we in this paper use a piecewise linearization method to extract its linear characteristics, following which we describe shock form with natural language through cloud model. In the process of acquisition, we use the exponential smoothing method to forecast the position where QRS wave may appear to assist QRS wave detection, and use template to judge whether current cardiac is sinus rhythm. And we choose some signals from MIT-BIH Arrhythmia Database to detect whether the algorithm is effective in Matlab. The results show that our method can correctly detect the changing trend of sinus heart rate. The proposed method can achieve real-time detection of sinus rhythm shocks, which is simple and easily implemented, so that it is effective as a supplementary method.
Skarda, R T; Muir, W W; Bednarski, R M; Hubbell, J A; Mason, D E
1995-01-01
The purpose of this study was to review the incidence of cardiac arrhythmias in 137 anesthetized dogs and 13 anesthetized cats with congenital or acquired heart disease that were referred for correction of following procedures: patent ductus arteriosus (PDA-ligation, 28%), cardiac catheterization with angiogram and angioplasty (22%), pacemaker implantation (18%), exploratory lateral thoracotomy (8.7%), correction of right aortic arch (ring anomaly, 3.3%), correction of subvalvular aortic stenosis (2.7%), correction of PDA with coil in patients with mitral regurgitation and congestive heart failure (2%), pericardectomy and removal of heart base tumor (2%), and palliative surgery for ventricular septal defect (VSD, 0.7%). The anesthetic plan considered the risks of anesthesia based upon the pathophysiology of cardiac lesions and the anesthetic drug effects on the cardiovascular system. Recommendations are made for dogs with decreased cardiac contractility, cardiac disease with volume overload, cardiac disease with pressure overload, and pericardial tamponade. The percentages of animals and their associated cardiac arrhythmias after premedication and during and after anesthesia were: sinus bradycardia (15.3%), sinus tachycardia (3.3%), atrial flutter (0.7%), atrial fibrillation (0.7%), premature ventricular contraction (14%), and ventricular tachycardia (1.3%). Prompt therapy was given to a percentage of animals in order to control arrhythmia and support cardiovascular system, by using atropine or glycopyrrolate (14%), lidocaine (17.3%), and dopamine (14.7%).(ABSTRACT TRUNCATED AT 250 WORDS)
SPEAR Trial: Smartphone Pediatric ElectrocARdiogram Trial
Nguyen, Hoang H.; Van Hare, George F.; Rudokas, Michael; Bowman, Tammy; Silva, Jennifer N. A.
2015-01-01
Objectives Smartphone-enabled ECG devices have the potential to improve patient care by enabling remote ECG assessment of patients with potential and diagnosed arrhythmias. This prospective study aimed to assess the usefulness of pediatric ECG tracings generated by the AliveCor device (Oklahoma City, OK) and to assess user satisfaction. Study Design Enrolled pediatric patients with documented paroxysmal arrhythmia used the AliveCor device over a yearlong study period. Pediatric electrophysiologists reviewed all transmitted ECG tracings. Patient completed surveys were analyzed to assess user satisfaction. Results 35 patients were enrolled with the following diagnoses: supraventricular tachycardia (SVT, 57%), atrial fibrillation (AF, 11%), ectopic atrial tachycardia (EAT, 6%), atrial tachycardia (AT, 3%), and ventricular tachycardia (VT, 23%). A total of 238 tracings were received from 20 patients, 96% of which were of diagnostic quality for sinus rhythm, sinus tachycardia, SVT, and AF. 126 patient satisfaction surveys (64% from parents) were completed. 98% of the survey responses indicated that it was easy to obtain tracings, 93% found it easy to transmit the tracings, 98% showed added comfort in managing arrhythmia by having the device, and 93% showed interest in continued use of the device after the study period ended. Conclusions Smartphone-enabled ECG devices can generate tracings of diagnostic quality in children. User satisfaction was extremely positive. Use of the device to manage certain patients with AF and SVT showcases the future role of remote ECGs in the successful outpatient management of arrhythmias in children by potentially reducing Emergency Department visits and healthcare costs. PMID:26295569
Atrial fibrillation in the elderly
Franken, Roberto A.; Rosa, Ronaldo F.; Santos, Silvio CM
2012-01-01
This review discusses atrial fibrillation according to the guidelines of Brazilian Society of Cardiac Arrhythmias and the Brazilian Cardiogeriatrics Guidelines. We stress the thromboembolic burden of atrial fibrillation and discuss how to prevent it as well as the best way to conduct cases of atrial fibrillatios in the elderly, reverting the arrhythmia to sinus rhythm, or the option of heart rate control. The new methods to treat atrial fibrillation, such as radiofrequency ablation, new oral direct thrombin inhibitors and Xa factor inhibitors, as well as new antiarrhythmic drugs, are depicted. PMID:22916053
Physiological Regulation and Infantile Anorexia: A Pilot Study
ERIC Educational Resources Information Center
Chatoor, Irene; Ganiban, Jody; Surles, Jaclyn; Doussard-Roosevelt, Jane
2004-01-01
Objective: To examine whether infantile anorexia is associated with physiological dysregulation. Method: This study included eight toddlers with infantile anorexia and eight healthy eaters matched for age, race, socioeconomic status, and gender. Physiological measures of heart period and respiratory sinus arrhythmia were assessed across three…
Sulik, Michael J; Eisenberg, Nancy; Spinrad, Tracy L; Silva, Kassondra M
2015-07-01
We tested whether respiratory sinus arrhythmia (RSA) reactivity in response to each of three self-regulation tasks (bird and dragon; knock-tap; and gift wrap) would predict self-regulation performance in a sample of 101 preschool-age children (M age = 4.49, SD = .64). While controlling for baseline RSA, decreases in RSA from bird and dragon to knock-tap (but not from baseline to bird and dragon) predicted a latent variable measuring self-regulation. Furthermore, increases in RSA from the knock-tap to gift wrap-the only task involving delay of gratification-were related to concurrent task performance while controlling for the relation between RSA reactivity and the latent self-regulation variable. Results suggest that the relations between RSA reactivity and self-regulatory ability are influenced by task-specific demands and possibly by task order. Furthermore, RSA reactivity appears to relate differently to performance on motivationally salient self-regulation tasks such as delay of gratification relative to cool executive function tasks. © 2015 Wiley Periodicals, Inc.
Overbeek, Thérèse J M; van Boxtel, Anton; Westerink, Joyce H D M
2012-09-01
The literature shows large inconsistencies in respiratory sinus arrhythmia (RSA) responses to induced emotional states. This may be caused by differences in emotion induction methods, RSA quantification, and non-emotional demands of the situation. In 83 healthy subjects, we studied RSA responses to pictures and film fragments eliciting six different discrete emotions relative to neutral baseline stimuli. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean heart rate and respiration rate, resulting in eight different RSA response measures. Subjective ratings of emotional stimuli and facial electromyographic responses indicated that pictures and film fragments elicited the intended emotions. Although RSA measures showed various emotional effects, responses were quite heterogeneous and frequently nonsignificant. They were substantially influenced by methodological factors, in particular time vs. frequency domain response measures, correction for changes in respiration rate, use of pictures vs. film fragments, and sex of participants. Copyright © 2012 Elsevier B.V. All rights reserved.
Respiratory sinus arrhythmia responses to cognitive tasks: effects of task factors and RSA indices.
Overbeek, Thérèse J M; van Boxtel, Anton; Westerink, Joyce H D M
2014-05-01
Many studies show that respiratory sinus arrhythmia (RSA) decreases while performing cognitive tasks. However, there is uncertainty about the role of contaminating factors such as physical activity and stress-inducing task variables. Different methods to quantify RSA may also contribute to variable results. In 83 healthy subjects, we studied RSA responses to a working memory task requiring varying levels of cognitive control and a perceptual attention task not requiring strong cognitive control. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean interbeat interval and respiration rate, resulting in eight different RSA indices. The two tasks were clearly differentiated by heart rate and facial EMG reference measures. Cognitive control induced inhibition of RSA whereas perceptual attention generally did not. However, the results show several differences between different RSA indices, emphasizing the importance of methodological variables. Age and sex did not influence the results. Copyright © 2014 Elsevier B.V. All rights reserved.
Respiratory sinus arrhythmia as a measure of cognitive workload.
Muth, Eric R; Moss, Jason D; Rosopa, Patrick J; Salley, James N; Walker, Alexander D
2012-01-01
The current standard for measuring cognitive workload is the NASA Task-load Index (TLX) questionnaire. Although this measure has a high degree of reliability, diagnosticity, and sensitivity, a reliable physiological measure of cognitive workload could provide a non-invasive, objective measure of workload that could be tracked in real or near real-time without interrupting the task. This study investigated changes in respiratory sinus arrhythmia (RSA) during seven different sub-sections of a proposed selection test for Navy aviation and compared them to changes reported on the NASA-TLX. 201 healthy participants performed the seven tasks of the Navy's Performance Based Measure. RSA was measured during each task and the NASA-TLX was administered after each task. Multi-level modeling revealed that RSA significantly predicted NASA-TLX scores. A moderate within-subject correlation was also found between RSA and NASA TLX scores. The findings support the potential development of RSA as a real-time measure of cognitive workload. Copyright © 2011. Published by Elsevier B.V.
Maternal Rearing Environment Impacts Autonomic Nervous System Activity
Bliss-Moreau, Eliza; Moadab, Gilda; Capitanio, John P.
2017-01-01
While it is now well known that social deprivation during early development permanently perturbs affective responding, accumulating evidence suggests that less severe restriction of the early social environment may also have deleterious effects. In the present report, we evaluate the affective responding of rhesus macaque (Macaca mulatta) infants raised by their mothers in restricted social environments or by their mothers in large social groups by indexing autonomic nervous system activity. Following a 25-hr evaluation of biobehavioral organization, electrocardiogram and an index of respiration were recorded for ten minutes. This allowed for an evaluation of both heart rate and respiratory sinus arrhythmia, an index of parasympathetic activity, during a challenging situation. Three to four month old infants raised in restricted social environments had significantly higher heart rates and lower respiratory sinus arrhythmia as compared to infants raised in unrestricted social environments, consistent with a more potent stress response to the procedure. These results are consistent with mounting evidence that the environment in which individuals are raised has important consequences for affective processing. PMID:28369889
Normalization of respiratory sinus arrhythmia by factoring in tidal volume.
Kobayashi, H
1998-09-01
The amplitude of respiratory sinus arrhythmia (RSA) was measured in eight healthy young male students with special reference to the effect of tidal volume (Vt). Under simultaneously controlled respiratory frequency and Vt, the heart rate variability (HRV) of the subjects was measured. While the respiratory frequency was adjusted to either 0.25 or 0.10 Hz, the Vt was controlled at 13 different volumes for each frequency. Linear relationships between RSA amplitude and Vt were observed and close correlations were obtained for 0.25 Hz compared with 0.10 Hz. However, regression equations showed a marked variation among subjects. Furthermore, RSA amplitude was related to vital capacity. Subjects who had lower vital capacity tended to show higher RSA amplitudes at the same Vt. Therefore, the ratio (% Vt) of Vt to vital capacity is a more effective index in normalizing RSA than raw tidal volume. From these results, we have proposed a normalized RSA (RSA amplitude/% Vt) as a new index of autonomic activity that provides a constant value regardless of Vt.
The relation of respiratory sinus arrhythmia to later shyness: Moderation by neighborhood quality.
Zhang, Hui; Spinrad, Tracy L; Eisenberg, Nancy; Zhang, Linlin
2018-05-21
The purpose of the study was to predict young children's shyness from both internal/biological (i.e., resting respiratory sinus arrhythmia; RSA) and external (i.e., neighborhood quality) factors. Participants were 180 children at 42 (Time 1; T1), 72 (T2), and 84 (T3) months of age. RSA data were obtained at T1 during a neutral film in the laboratory. Mothers reported perceived neighborhood quality at T2 and children's dispositional shyness at T1 and T3. Path analyses indicated that resting RSA interacted with neighborhood quality to predict T3 shyness, even after controlling for earlier family income and T1 shyness. Specifically, high levels of resting RSA predicted low levels of shyness in the context of high neighborhood quality. When neighborhood quality was low, resting RSA was positively related to later shyness. These findings indicate that children's shyness is predicted by more than biological processes and that consideration of the broader context is critical to understanding children's social behavior. © 2018 Wiley Periodicals, Inc.
Yaptangco, Mona; Crowell, Sheila E; Baucom, Brian R; Bride, Daniel L; Hansen, Erik J
2015-09-01
Major depressive disorder (MDD) is a debilitating and prevalent disorder associated with lower quality of life and substantial economic burden. Recently, there has been strong interest in respiratory sinus arrhythmia (RSA) as a biological predictor of later depression. Theoretical work suggests that higher resting RSA indexes physiological flexibility and better emotion regulation whereas lower RSA may mark vulnerability for psychopathology. However, empirical findings have varied. This study examined whether lower resting RSA predicted later depressive symptoms in a sample of healthy young adults across one year (n=185). Results indicate that year one (Y1) resting RSA predicted Y2 depressive symptoms. This finding remained significant when accounting for the stability of RSA and depressive symptoms across both time points and when including trait anxiety, body mass index, and medication use in statistical models. Findings provide further support for RSA as a promising biological marker for understanding and predicting depressive symptoms. Copyright © 2015 Elsevier B.V. All rights reserved.
Does respiratory sinus arrhythmia occur in fishes?
Campbell, Hamish A; Taylor, Edwin W; Egginton, Stuart
2005-01-01
The hypothesis that respiratory modulation of heart rate variability (HRV) or respiratory sinus arrhythmia (RSA) is restricted to mammals was tested on four Antarctic and four sub-Antarctic species of fish, that shared close genotypic or ecotypic similarities but, due to their different environmental temperatures, faced vastly different selection pressures related to oxygen supply. The intrinsic heart rate (fH) for all the fish species studied was ∼25% greater than respiration rate (fV), but vagal activity successively delayed heart beats, producing a resting fH that was synchronized with fV in a progressive manner. Power spectral statistics showed that these episodes of relative bradycardia occurred in a cyclical manner every 2–4 heart beats in temperate species but at >4 heart beats in Antarctic species, indicating a more relaxed selection pressure for cardio-respiratory coupling. This evidence that vagally mediated control of fH operates around the ventilatory cycle in fish demonstrates that influences similar to those controlling RSA in mammals operate in non-mammalian vertebrates. PMID:17148239
Chen, Ying; Wu, Zhong; Yang, Cuiwei; Shao, Jun; Wong, Kelvin Kian Loong; Abbott, Derek
2012-09-01
Atrial fibrillation (AF) can result in life-threatening arrhythmia, and a clinically convenient means for detecting vulnerability remains elusive. We investigated atrial vulnerability by analyzing the sinus electrogram (EG) from AF animal models using a phase synchronization method. Using acetylcholine (ACh)-induced acute canine AF models (n= 4), a total of 128 electrical leads were attached to the surface of the anterior and posterior atria, and the pulmonary veins to form an electrocardiological mapping system. ACh was injected at varying concentrations with ladder-type adjustments. Sinus EGs and induced AF EGs that pertain to specific ACh concentrations were recorded.We hypothesize that the atrial vulnerability may be correlated with the Shannon entropy (SE) of the phase difference matrix that is extracted from the sinus EG. Our research suggests that the combination of SE with the synchronization method enables the sinus node EG to be analyzed and used to estimate atrial vulnerability.
Physiological and Emotional Reactivity to Learning and Frustration
ERIC Educational Resources Information Center
Lewis, Michael; Hitchcock, Daniel F. A.; Sullivan, Margaret Wolan
2004-01-01
This study examined the behavioral (arm, facial) and autonomic (heart rate, respiratory sinus arrhythmia [RSA], and adrenocortical axis) reactivity of 56 4-month-old infants in response to contingency learning and extinction-induced frustration. During learning, infants displayed increases in operant arm response and positive emotional…
ECG changes in factory workers exposed to 27.2 MHz radiofrequency radiation.
Chen, Qingsong; Xu, Guoyong; Lang, Li; Yang, Aichu; Li, Shilin; Yang, Liwen; Li, Chaolin; Huang, Hanlin; Li, Tao
2013-05-01
To research the effect of 27.2 MHz radiofrequency radiation on electrocardiograms (ECG), 225 female workers operating radiofrequency machines at a shoe factory were chosen as the exposure group and 100 female workers without exposure from the same factory were selected as the control group. The 6 min electric field strength that the female workers were exposed to was 64.0 ± 25.2 V/m (mean ± SD), which exceeded 61 V/m, the International Commission on Non-Ionizing Radiation Protection reference root mean square levels for occupational exposure. A statistical difference was observed between the exposed group and the control group in terms of the rate of sinus bradycardia (χ(2) = 11.48, P = 0.003). When several known risk factors for cardiovascular disease were considered, including smoking, age, alcohol ingestion habit, and so on, the exposure duration was not an effective factor for ECG changes, sinus arrhythmia, or sinus bradycardia according to α = 0.05, while P = 0.052 for sinus arrhythmia was very close to 0.05. We did not find any statistical difference in heart rate, duration of the QRS wave (ventricular depolarization), or corrected QT intervals (between the start of the Q wave and end of the T wave) between the exposed and control groups. Occupational exposure to radiofrequency radiation was not found to be a cause of ECG changes after consideration of the confounding factors. Copyright © 2012 Wiley Periodicals, Inc.
Larsson, Maria Helena M A; Coelho, Fernanda M; Oliveira, Valéria M C; Yamaki, Fernanda L; Pereira, Guilherme G; Soares, Elaine C; Fedullo, José Daniel L; Pereira, Roberto C; Ito, F H
2008-09-01
Twenty-seven healthy captive lions (Panthera leo) and 13 healthy captive tigers (Panthera tigris) from São Paulo Zoo (Fundação Parque Zoológico de Sã Paulo, São Paulo, Brazil) collection were selected for this study. They were anesthetized with ketamine (10 mg/kg) combined with xylazine (1-2 mg/kg) for physical examinations, hematologic and serum chemical analysis and electrocardiogram recording. The main aim of this research was to gather initial information about normal electrocardiographic parameters of large felids. Standard P-QRS-T deflections on leads described for domestic carnivores were analyzed, and they did not greatly differ from those of large felids, taking into account the greater weight and corporal mass of large felids. Heart rate of lions ranged from 42 to 76 beats per minute (bpm). Heart rate of tigers ranged from 56 to 97 bpm. In both species, the most common rhythm detected was normal sinus rhythm followed by sinus arrhythmia; wandering pacemaker was also observed with normal sinus rhythm or sinus arrhythmia. Mean electrical axis lay between +60 degrees and +120 degrees. QRS complexes were predominantly positive in leads DI, DII, DIII, and AVF, and negative in AVR and AVL. This study provides insights into normal electrocardiograms of large felids. Wider investigations on the same subject are necessary to establish criteria for the recognition of abnormalities in these species and should include other anesthetic drug(s) combinations and reports of electrocardiographic features of animals with cardiac disease and electrolytes disturbances.
Management of Arrhythmias in Heart Failure
Masarone, Daniele; Limongelli, Giuseppe; Rubino, Marta; Valente, Fabio; Vastarella, Rossella; Ammendola, Ernesto; Gravino, Rita; Verrengia, Marina; Salerno, Gemma; Pacileo, Giuseppe
2017-01-01
Heart failure patients are predisposed to develop arrhythmias. Supraventricular arrhythmias can exacerbate the heart failure symptoms by decreasing the effective cardiac output and their control require pharmacological, electrical, or catheter-based intervention. In the setting of atrial flutter or atrial fibrillation, anticoagulation becomes paramount to prevent systemic or cerebral embolism. Patients with heart failure are also prone to develop ventricular arrhythmias that can present a challenge to the managing clinician. The management strategy depends on the type of arrhythmia, the underlying structural heart disease, the severity of heart failure, and the range from optimization of heart failure therapy to catheter ablation. Patients with heart failure, irrespective of ejection fraction are at high risk for developing sudden cardiac death, however risk stratification is a clinical challenge and requires a multiparametric evaluation for identification of patients who should undergo implantation of a cardioverter defibrillator. Finally, patients with heart failure can also develop symptomatic bradycardia, caused by sinus node dysfunction or atrio-ventricular block. The treatment of bradycardia in these patients with pacing is usually straightforward but needs some specific issue. PMID:29367535
Borderline Personality Disorder and Emotion Regulation: Insights from the Polyvagal Theory
ERIC Educational Resources Information Center
Austin, Marilyn A.; Riniolo, Todd C.; Porges, Stephen W.
2007-01-01
The current study provides the first published evidence that the parasympathetic component of the autonomic nervous system differentiates the response profiles between individuals diagnosed with borderline personality disorder (BPD) and controls. Respiratory sinus arrhythmia (RSA), a non-invasive marker of the influence of the myelinated vagal…
Vagal Reactivity and Affective Adjustment in Infants during Interaction Challenges.
ERIC Educational Resources Information Center
Bazhenova, Olga V.; Plonskaia, Oxana; Porges, Stephen W.
2001-01-01
Evaluated respiratory sinus arrhythmia (RSA) and heart period in 5-month-olds during interaction challenges. Found that during object-mediated challenge, RSA increases were uniquely related to positive engagement. During person-mediated challenge, subjects showed more complex integration of autonomic and behavioral responses such that only infants…
Autonomic Dysregulation during Sensory Stimulation in Children with Autism Spectrum Disorder
ERIC Educational Resources Information Center
Schaaf, Roseann C.; Benevides, Teal W.; Leiby, Benjamin E.; Sendecki, Jocelyn A.
2015-01-01
Autonomic nervous system (ANS) activity during sensory stimulation was measured in 59 children with autism spectrum disorder (ASD) ages 6-9 in comparison to 30 typically developing controls. Multivariate comparisons revealed significant differences between groups in the respiratory sinus arrhythmia (parasympathetic measure) vector of means across…
ERIC Educational Resources Information Center
Blandon, Alysia Y.; Calkins, Susan D.; Keane, Susan P.; O'brien, Marion
2010-01-01
Trajectories of children's temperamental reactivity (negative affectivity and surgency) were examined in a community sample of 370 children across the ages of 4 to 7 with hierarchical linear modeling. Children's physiological reactivity (respiratory sinus arrhythmia [RSA]), physiological regulation ([delta]RSA), and maternal parenting behavior…
Physiological Reactivity to Infant Crying and Observed Maternal Sensitivity
ERIC Educational Resources Information Center
Joosen, Katharina J.; Mesman, Judi; Bakermans-Kranenburg, Marian J.; Pieper, Suzanne; Zeskind, Philip S.; van IJzendoorn, Marinus H.
2013-01-01
Relations between maternal sensitivity and physiological reactivity to infant crying were examined using measures of heart rate (HR) and respiratory sinus arrhythmia (RSA) in 49 mothers of second-born infants. Using the Ainsworth Sensitivity Scale, an independent assessment of maternal sensitivity was made during maternal free play and bathing of…
Liu, Enzhao; Xu, Gang; Liu, Tong; Ye, Lan; Zhang, Qitong; Zhao, Yanshu; Li, Guangping
2015-03-01
Discrete potentials (DPs) have been recorded and targeted as the site of ablation of the outflow tract arrhythmias. The aim of the present study was to investigate the significance of DPs with respect to mapping and ablation for idiopathic outflow tract premature ventricular contractions (PVCs) or ventricular tachycardias (VTs). Seventeen consecutive patients with idiopathic right or left ventricular outflow tract PVCs/VTs who underwent radiofrequency catheter ablation were included. Intracardiac electrograms during the mapping and ablation were analysed. During sinus rhythm, sharp high-frequency DPs that displayed double or multiple components were recorded following or buried in the local ventricular electrograms in all of the 17 patients, peak amplitude 0.51 ± 0.21 mV. The same potential was recorded prior to the local ventricular potential of the PVCs/VTs. Spontaneous reversal of the relationship of the DPs to the local ventricular electrogram during the arrhythmias was noted. The DPs were related to a region of low voltage showed by intracardiac high-density contact mapping. At the sites with DPs, lower unipolar and bipolar ventricular voltage of sinus beats were noted compared with the adjacent regions without DPs (unipolar: 6.1 ± 1.8 vs. 8.3 ± 2.3 mV, P < 0.05; bipolar: 0.62 ± 0.45 vs. 1.03 ± 0.60 mV, P < 0.05). The targeted DPs were still present in 12 patients after successful elimination of the ectopies. Discrete potentials were not present in seven controls. Discrete potentials and related low-voltage regions were common in idiopathic outflow tract ventricular arrhythmias. Discrete potential- and substrate-guided ablation strategy will help to reduce the recurrence of idiopathic outflow tract arrhythmias. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.
Moak, Jeffrey P; Mercader, Marco A; He, Dingchao; Trachiotis, Gregory; Langert, Joshua; Blicharz, Andy; Montaque, Erin; Li, Xiyan; Cheng, Yao I; McCarter, Robert; Bornzin, Gene A; Martin, Gerard R; Jonas, Richard A
2013-06-01
Supraventricular arrhythmias (junctional ectopic tachycardia [JET] and atrial tachyarrhythmias) frequently complicate recovery from open heart surgery in children and can be difficult to manage. Medical treatment of JET can result in significant morbidity. Our goal was to develop a nonpharmacological approach using autonomic stimulation of selective fat pad (FP) regions of the heart in a young canine model of open heart surgery to control 2 common postoperative supraventricular arrhythmias. Eight mongrel dogs, varying in age from 5 to 8 months and weighting 22±4 kg, underwent open heart surgery replicating a nontransannular approach to tetralogy of Fallot repair. Neural stimulation of the right inferior FP was used to control the ventricular response to supraventricular arrhythmias. Right inferior FP stimulation decreased baseline AV nodal conduction without altering sinus cycle length. AV node Wenckebach cycle length prolonged from 270±33 to 352±89 ms, P=0.02. Atrial fibrillation occurred in 7 animals, simulating a rapid atrial tachyarrhythmias. FP stimulation slowed the ventricular response rate from 166±58 to 63±29 beats per minute, P<0.001. Postoperative JET occurred in 7 dogs. FP stimulation slowed the ventricular rate during postoperative JET from 148±31 to 106±32 beats per minute, P<0.001, and restored sinus rhythm in 7/7 dogs. Right inferior FP stimulation had a selective effect on the AV node, and slowed the ventricular rate during postoperative JET and atrial tachyarrhythmias in our young canine open heart surgery model. FP stimulation may be a useful new technique for managing children with JET and atrial tachyarrhythmias.
Cardiac Vagal Regulation and Early Peer Status
ERIC Educational Resources Information Center
Graziano, Paulo A.; Keane, Susan P.; Calkins, Susan D.
2007-01-01
A sample of 341 5 1/2-year-old children participating in an ongoing longitudinal study was the focus of a study on the relation between cardiac vagal regulation and peer status. To assess cardiac vagal regulation, resting measures of respiratory sinus arrhythmia (RSA) and RSA change (suppression) to 3 cognitively and emotionally challenging tasks…
ERIC Educational Resources Information Center
El-Sheikh, Mona; Kouros, Chrystyna D.; Erath, Stephen; Cummings, E. Mark; Keller, Peggy; Staton, Lori
2009-01-01
Toward greater specificity in the prediction of externalizing problems in the context of interparental conflict, interactions between children's parasympathetic and sympathetic nervous system (PNS and SNS) activity were examined as moderators. PNS activity was indexed by respiratory sinus arrhythmia (RSA) and RSA reactivity (RSA-R) to lab…
Respiratory Sinus Arrhythmia Predicts Restricted Repetitive Behavior Severity
ERIC Educational Resources Information Center
Condy, Emma E.; Scarpa, Angela; Friedman, Bruce H.
2017-01-01
In addition to social communication deficits, restricted repetitive behaviors (RRBs) are a key diagnostic feature of autism spectrum disorder (ASD). Dysfunction of the autonomic nervous system (ANS) in ASD has been posited as a mechanism of RRBs; however, most studies investigating ANS activity in ASD have focused on its relation to social…
ERIC Educational Resources Information Center
Wagner, Nicholas; Mills-Koonce, Roger; Willoughby, Michael; Propper, Cathi; Rehder, Peter; Gueron-Sela, Noa
2017-01-01
Extant literature suggests that oppositional defiant disorder (ODD) and callous-unemotional (CU) behaviors in childhood and adolescence are associated with distinct patterns of psychophysiological functioning, and that individual differences in these patterns have implications for developmental pathways to disorder. Very little is known about the…
ERIC Educational Resources Information Center
Diamond, Lisa M.; Fagundes, Christopher P.; Cribbet, Matthew R.
2012-01-01
The present study tested whether individual differences in autonomic nervous system functioning interact with environmental risk factors to predict adolescents' psychosocial functioning. The authors assessed skin conductance and respiratory sinus arrhythmia at rest and during laboratory stressors in 110 14-year-olds. Subsequently, adolescents and…
ERIC Educational Resources Information Center
Musser, Erica D.; Backs, Richard W.; Schmitt, Colleen F.; Ablow, Jennifer C.; Measelle, Jeffery R.; Nigg, Joel T.
2011-01-01
Despite growing interest in conceptualizing ADHD as involving disrupted emotion regulation, few studies have examined the physiological mechanisms related to emotion regulation in children with this disorder. This study examined parasympathetic and sympathetic nervous system reactivity via measures of respiratory sinus arrhythmia (RSA) and cardiac…
ERIC Educational Resources Information Center
Dietrich, Andrea; Riese, Harriette; Sondeijker, Frouke E. P. L.; Greaves-Lord, Kirstin; van Roon, Arie M.; Ormel, Johan; Neeleman, Jan; Rosmalen, Judith G. M.
2007-01-01
Objective: To investigate whether externalizing and internalizing problems are related to lower and higher heart rate (HR), respectively, and to explore the relationship of these problems with respiratory sinus arrhythmia (RSA) and baroreflex sensitivity (BRS). Moreover, to study whether problems present at both preschool and preadolescent age…
ERIC Educational Resources Information Center
Shenk, Chad E.; Putnam, Frank W.; Noll, Jennie G.
2012-01-01
Objective: Not every adolescent exposed to child maltreatment develops symptoms of post-traumatic stress disorder (PTSD), emphasizing the need to identify variables that explain how some maltreated children come to develop these symptoms. This study tested whether a set of variables, respiratory sinus arrhythmia (RSA) and cortisol reactivity as…
ERIC Educational Resources Information Center
Ablow, Jennifer C.; Marks, Amy K.; Shirley Feldman, S.; Huffman, Lynne C.
2013-01-01
Associations among 53 primiparous women's Adult Attachment Interview classifications (secure-autonomous vs. insecure-dismissing) and physiological and self-reported responses to infant crying were explored. Heart rate, skin conductance levels, and respiratory sinus arrhythmia (RSA) were recorded continuously. In response to the cry,…
The Effects of Respiratory Sinus Arrhythmia on Anger Reactivity and Persistence in Major Depression
Ellis, Alissa J.; Shumake, Jason; Beevers, Christopher G.
2016-01-01
The experience of anger during a depressive episode has recently been identified as a poor prognostic indicator of illness course. Given the clinical implications of anger in major depressive disorder (MDD), understanding the mechanisms involved in anger reactivity and persistence is critical for improved intervention. Biological processes involved in emotion regulation during stress, such as respiratory sinus arrhythmia (RSA), may play a role in maintaining negative moods. Clinically depressed (MDD) (n=49) and non-depressed (non-MDD) (n=50) individuals were challenged with a stressful computer task shown to increase anger, while RSA (high frequency range 0.15–0.4 Hz) was collected. RSA predicted future anger, but was unrelated to current anger. That is, across participants, low baseline RSA predicted anger reactivity during the task, and in depressed individuals, those with low RSA during the task had a greater likelihood of anger persistence during a recovery period. These results suggest that low RSA may be a psychophysiological process involved in anger regulation in depression. Low RSA may contribute to sustained illness course by diminishing the repair of angry moods. PMID:27401801
Neural network for photoplethysmographic respiratory rate monitoring
NASA Astrophysics Data System (ADS)
Johansson, Anders
2001-10-01
The photoplethysmographic signal (PPG) includes respiratory components seen as frequency modulation of the heart rate (respiratory sinus arrhythmia, RSA), amplitude modulation of the cardiac pulse, and respiratory induced intensity variations (RIIV) in the PPG baseline. The aim of this study was to evaluate the accuracy of these components in determining respiratory rate, and to combine the components in a neural network for improved accuracy. The primary goal is to design a PPG ventilation monitoring system. PPG signals were recorded from 15 healthy subjects. From these signals, the systolic waveform, diastolic waveform, respiratory sinus arrhythmia, pulse amplitude and RIIV were extracted. By using simple algorithms, the rates of false positive and false negative detection of breaths were calculated for each of the five components in a separate analysis. Furthermore, a simple neural network (NN) was tried out in a combined pattern recognition approach. In the separate analysis, the error rates (sum of false positives and false negatives) ranged from 9.7% (pulse amplitude) to 14.5% (systolic waveform). The corresponding value of the NN analysis was 9.5-9.6%.
Taylor, Zoe E.; Eisenberg, Nancy; Spinrad, Tracy L.
2015-01-01
The goal of this study was to examine physiological and environmental predictors of children’s sympathy (an emotional response consisting of feelings of concern or sorrow for others who are distressed or in need) and whether temperamental effortful control mediated these relations. Specifically, in a study of 192 children (23% Hispanic; 54% male), respiratory sinus arrhythmia (RSA), a measure thought to reflect physiological regulation, and observed authoritative parenting (both at 42 months) were examined as predictors of children’s effortful control (at 54 months) and, in turn, children’s sympathy (at 72 and 84 months). Measures of both baseline RSA and RSA suppression were examined. In a structural equation model, observed parenting was positively related to children’s subsequent sympathy through its positive relation to effortful control. Furthermore, the indirect path from baseline RSA to higher sympathy through effortful control was marginally significant. Authoritative parenting and baseline RSA uniquely predicted individual differences in children’s effortful control. Findings highlight the potential role of both authoritative parenting and physiological regulation in the development of children’s sympathy. PMID:25329555
Atrial fibrillation pearls and perils of management.
Kudenchuk, P J
1996-01-01
Atrial fibrillation, a common arrhythmia, is responsible for considerable cardiovascular morbidity. Its management demands more than antiarrhythmic therapy alone, but must address the causes and consequences of the arrhythmia. Although remediable causes are infrequently found, a thorough search for associated heart disease or its risk factors results in better-informed patient management. Controlling the ventricular response and protecting from thromboembolic complications are important initial goals of therapy and may include the administration of aspirin in younger, low-risk patients. Older patients and those with risk factors for systemic embolism are not adequately protected from stroke complications by aspirin therapy alone. It remains controversial whether all high-risk patients should receive warfarin and at what intensity. Whether and how sinus rhythm should be restored and maintained poses the greatest therapeutic controversy for atrial fibrillation. The mortal risk of antiarrhythmic therapy is substantially greater in patients with evidence of heart failure. In such persons, the risks and benefits of maintaining normal sinus rhythm with antiarrhythmic medications should be weighted carefully. A definitive cure for atrial fibrillation remains elusive, but promising surgical and catheter ablation therapies are being developed. PMID:8686300
Aults, Christopher D; Cooper, Patrick J; Pauletti, Rachel E; Jones, Nancy Aaron; Perry, David G
2015-12-01
Previous studies have examined sex differences in physiological responding, including respiratory sinus arrhythmia (RSA) reactivity in response to changing stimulus conditions involving situation specific or gender related cues, in children and adolescents. The present study examined whether RSA reactivity moderates the relation between aggression and internalizing symptoms and whether there are sex differences in this effect. Participants were 82 adolescents (M age = 12.1 years; 44 girls) from the general middle-school population. Peer nominations assessed aggression and internalizing symptoms, and RSA reactivity (defined as change in RSA from baseline to task) was recorded while participants anticipated and responded to an 85 dB signaled white-noise burst. For girls, internalizing symptoms were associated with aggression only if girls showed low RSA reactivity from baseline to task; there was no effect for boys. This association was absent when girls showed high RSA reactivity. Thus, child sex appears to influence not only levels of physiological responding but also relations of physiological responding to comorbidity of adjustment problems.
Taylor, Zoe E; Eisenberg, Nancy; Spinrad, Tracy L
2015-01-01
The goal of this study was to examine physiological and environmental predictors of children's sympathy (an emotional response consisting of feelings of concern or sorrow for others who are distressed or in need) and whether temperamental effortful control mediated these relations. Specifically, in a study of 192 children (23% Hispanic; 54% male), respiratory sinus arrhythmia (RSA), a measure thought to reflect physiological regulation, and observed authoritative parenting (both at 42 months) were examined as predictors of children's effortful control (at 54 months) and, in turn, children's sympathy (at 72 and 84 months). Measures of both baseline RSA and RSA suppression were examined. In a structural equation model, observed parenting was positively related to children's subsequent sympathy through its positive relation to effortful control. Furthermore, the indirect path from baseline RSA to higher sympathy through effortful control was marginally significant. Authoritative parenting and baseline RSA uniquely predicted individual differences in children's effortful control. Findings highlight the potential role of both authoritative parenting and physiological regulation in the development of children's sympathy.
Psychological, autonomic, and serotonergic correlates of parasuicide among adolescent girls.
Crowell, Sheila E; Beauchaine, Theodore P; McCauley, Elizabeth; Smith, Cindy J; Stevens, Adrianne L; Sylvers, Patrick
2005-01-01
Although parasuicidal behavior in adolescence is poorly understood, evidence suggests that it may be a developmental precursor of borderline personality disorder (BPD). Current theories of both parasuicide and BPD suggest that emotion dysregulation is the primary precipitant of self-injury, which serves to dampen overwhelmingly negative affect. To date, however, no studies have assessed endophenotypic markers of emotional responding among parasuicidal adolescents. In the present study, we compare parasuicidal adolescent girls (n=23) with age-matched controls (n=23) on both psychological and physiological measures of emotion regulation and psychopathology. Adolescents, parents, and teachers completed questionnaires assessing internalizing and externalizing psychopathology, substance use, trait affectivity, and histories of parasuicide. Psychophysiological measures including electrodermal responding (EDR), respiratory sinus arrhythmia, and cardiac pre-ejection period (PEP) were collected at baseline, during negative mood induction, and during recovery. Compared with controls, parasuicidal adolescents exhibited reduced respiratory sinus arrhythmia (RSA) at baseline, greater RSA reactivity during negative mood induction, and attenuated peripheral serotonin levels. No between-group differences on measures of PEP or EDR were found. These results lend further support to theories of emotion dysregulation and impulsivity in parasuicidal teenage girls.
Obstructive sleep apnoea-hypopnoea and arrhythmias: new updates.
Vizzardi, Enrico; Sciatti, Edoardo; Bonadei, Ivano; D'Aloia, Antonio; Curnis, Antonio; Metra, Marco
2017-07-01
Obstructive sleep apnoea-hypopnoea (OSAH) is a prevalent condition characterized by repetitive pharyngeal collapse during sleep, leading to hypoxemia, hypercapnia, and persistent inspiratory efforts against an occluded airway until arousal. Several studies demonstrated that OSAH exerts acute and chronic effects on the cardiovascular system. Thus, although being a respiratory problem, the most important consequences of OSAH are cardiovascular, among which there are arrhythmias. The purpose of this review is to systematically analyse what has been recently published about the relationship between OSAH and every cardiac arrhythmia separately. We searched Pubmed, Scopus, Web of Science and Cochrane Collaboration databases for 'OSAHS arrhythmias', 'OSAH arrhythmias' and 'OSA arrhythmias'. We analyse 1298 articles and meta-analyses, excluding already edited reviews. Arrhythmias, especially of ventricular origin, are frequent in OSAH. Ventricular premature beats, couplets and ventricular tachycardia runs are even more frequent in patients suffering from heart failure. They may be due to left heart remodelling, overwork and ischaemia and can explain at least some sudden deaths occurring between midnight and 6 a.m. Sinus pauses and atrioventricular blocks are increased according to the severity of the disturbance and may be reduced by continuous positive airway pressure therapy, preventing pace-maker implantation. Finally, atrial fibrillation, resistance against antiarrhythmic drugs and recurrences after surgical procedures are strongly related to OSAH. Arrhythmias are frequent in OSAH. Treatment of OSAH may reduce some of them. An implantable cardioverter-defibrillator and continuous positive airway pressure should be considered in some patients.
Cosio, F G; Palacios, J; Vidal, J M; Cocina, E G; Gómez-Sánchez, M A; Tamargo, L
1983-01-01
Extrastimulus-induced intraatrial conduction delays were measured in 12 patients with documented episodes of atrial fibrillation (AF) by recording atrial electrograms at the high right atrium, His bundle region, and coronary sinus. Seventeen patients with and without heart disease, but without atrial arrhythmias served as the control group. During baseline-paced atrial rhythms, a conduction delay zone could be delineated, near the atrial effective refractory period, during which all extrastimuli produced conduction delays. When compared at the same paced cycle lengths (500 to 650 ms), the patients with AF had shorter atrial effective refractory periods (mean +/- standard deviation 206 +/- 24.1 versus 233 +/- 28.2 in control patients, p less than 0.02), wider conduction delay zones (79 +/- 21.7 ms versus 52 +/- 21 in control patients, p less than 0.01), and longer conduction delays both to the His bundle region (64 +/- 18.3 ms versus 35 +/- 21.7 in control patients, p less than 0.005) and the coronary sinus (76 +/- 18.9 ms versus 35 +/- 16.1 in control patients, p less than 0.001). Repetitive atrial responses were recorded in 6 patients with AF and in 9 control subjects. Sinus nodal function abnormalities were detected in 6 of the patients with fibrillation. Patients with AF had a higher tendency than control subjects to develop slow intraatrial conduction, as well as shorter effective refractory periods. Since both features would favor reentry, they may be the electrophysiologic manifestations of the abnormalities making these patients prone to atrial reentrant arrhythmias. Repetitive atrial responses were of no predictive value. Sinus nodal dysfunction was frequently found, but was not essential for the occurrence of AF.
Spitzer, Stefan G; Wacker, Petra; Gazarek, Steffen; Malinowski, Klaus; Schibgilla, Volker
2009-12-01
PASTA (pacing of the atria in sinus node disease) is a prospective and randomized trial, assessing the effect of different atrial lead positions on the atrial fibrillation (AF) incidence in patients with sinus node disease (SND). The atrial lead position is randomized to: (a) free right atrial wall, (b) right atrial appendage (RAA), (c) coronary sinus ostium (CS-Os), or (d) dual site right atrial pacing (CS-Os + RAA). The pacemakers (Vitatron Selection 9000 or Prevent AF, Vitatron B.V., Arnhem, The Netherlands) are programmed in DDDR 70 mode and the total follow-up duration is 24 months. To describe the atrial rhythm state, pacemaker-derived data (arrhythmia counter) were assessed for AF episodes. AF was considered as evident, if the AF burden (time in AF related to follow-up interval) was >1% (i.e., 15 min/d). Follow-up data after 24 months were evaluated. The analysis evaluates 142 patients (77 male, 74.5 +/- 7.8 years). There was no statistical significant difference with respect to the occurrence of AF between the four groups after 24 months (A: 36%; B: 38%, C: 32%, D: 48%). The percentage of atrial/ventricular pacing was in A: 78/76%, in B: 84/81%, in C: 70/65%, and in D: 79/69%. These differences were not significant. The evaluation of the AF burden >1% and the total AF burden after 24 months did not show differences in the incidence of AF in patients with dual chamber pacemaker therapy for SND. We were not able to demonstrate a significant influence of right atrial lead position on the incidence of AF recurrence.
Frailty syndrome in patients with heart rhythm disorders.
Mlynarska, Agnieszka; Mlynarski, Rafal; Golba, Krzysztof S
2017-09-01
To assess the prevalence of frailty syndrome in patients with heart rhythm disorders that qualified for pacemaker implantation. The study included 171 patients (83 women, aged 73.9 ± 6.7 years) who qualified for pacemaker implantation as a result of sinus node dysfunction (81 patients) or atrio-ventricular blocks (AVB; 90 patients). A total of 60 patients (25 women, aged 72.40 ± 7.09 years) without heart rhythm disorders were included in the control group. Frailty syndrome was diagnosed using the Canadian Study of Health and Aging Clinical Frailty Scale test. Frailty syndrome was diagnosed in 25.15% of the patients, and pre-frailty in 36.84% of the patients. Frailty syndrome was diagnosed in 10% of the control group, and the average value of frailty was 3.35 ± 0.92. Frailty occurred significantly more often among patients with AVB (33.34%) compared with patients who were diagnosed with sinus node dysfunction (16.05%); P = 0.0081. The average score of frailty for sinus node dysfunction was 3.71 ± 0.89, and for AVB it was 4.14 ± 0.93; P = 0.0152. In the case of AVB, the women had a statistically more intense level of frailty of 4.54 ± 0.90 as compared with the men 3.87 ± 0.85; P = 0.0294. In the multiple logistic analysis, the presence of any arrhythmia was strongly associated with frailty syndrome (OR 2.1286, 95% CI 1.4594 - 3.1049; P = 0.0001). Frailty syndrome was diagnosed in one-quarter of patients with cardiac arrhythmias, whereas a further 40% were at a higher risk of frailty syndrome, and its occurrence was significantly higher if compared with the control group. Frailty occurred significantly more often among patients with atrio-ventricular blocks, especially in women. The results of the present research showed that there is a statistical association between frailty and arrhythmias. Geriatr Gerontol Int 2017; 17: 1313-1318. © 2016 Japan Geriatrics Society.
Surgical Ablation of Atrial Fibrillation Using Energy Sources.
Brick, Alexandre Visconti; Braile, Domingo Marcolino
2015-01-01
Surgical ablation, concomitant with other operations, is an option for treatment in patients with chronic atrial fibrillation. The aim of this study is to present a literature review on surgical ablation of atrial fibrillation in patients undergoing cardiac surgery, considering energy sources and return to sinus rhythm. A comprehensive survey was performed in the literature on surgical ablation of atrial fibrillation considering energy sources, sample size, study type, outcome (early and late), and return to sinus rhythm. Analyzing studies with immediate results (n=5), the percentage of return to sinus rhythm ranged from 73% to 96%, while those with long-term results (n=20) (from 12 months on) ranged from 62% to 97.7%. In both of them, there was subsequent clinical improvement of patients who underwent ablation, regardless of the energy source used. Surgical ablation of atrial fibrillation is essential for the treatment of this arrhythmia. With current technology, it may be minimally invasive, making it mandatory to perform a procedure in an attempt to revert to sinus rhythm in patients requiring heart surgery.
Wozniak, Jacek; Dabrowski, Rafal; Luczak, Dariusz; Kwiatkowska, Malgorzata; Musiej-Nowakowska, Elzbieta; Kowalik, Ilona; Szwed, Hanna
2009-01-01
To evaluate possible disturbances in autonomic regulation and cardiac arrhythmias in children with localized and systemic scleroderma. There were 40 children included in the study: 20 with systemic and 20 with localized scleroderma. The control group comprised 20 healthy children. In 24-hour Holter recording, the average rate of sinus rhythm was significantly higher in the groups with systemic and localized scleroderma than in the control group, but there was no significant difference between them. The variability of heart rhythm in both groups was significantly decreased. In the group with systemic scleroderma, single supraventricular ectopic beats were observed in 20% and runs were seen in 40% of patients. In the group with localized scleroderma, supraventricular single ectopic beats occurred in 35% of patients and runs in 45% of those studied. Ventricular arrhythmia occurred in 2 children with systemic scleroderma, but in 1 child, it was complex. The most frequent cardiac arrhythmias in both types of scleroderma in children were of supraventricular origin, whereas ventricular arrhythmias did not occur very often. There were no significant differences in autonomic disturbances manifesting as a higher heart rate and decreased heart rate variability between localized and systemic scleroderma.
Lerma, Claudia; Wessel, Niels; Schirdewan, Alexander; Kurths, Jürgen; Glass, Leon
2008-07-01
The objective was to determine the characteristics of heart rate variability and ventricular arrhythmias prior to the onset of ventricular tachycardia (VT) in patients with an implantable cardioverter defibrillator (ICD). Sixty-eight beat-to-beat time series from 13 patients with an ICD were analyzed to quantify heart rate variability and ventricular arrhythmias. The episodes of VT were classified in one of two groups depending on whether the sinus rate in the 1 min preceding the VT was greater or less than 90 beats per minute. In a subset of patients, increased heart rate and reduced heart rate variability was often observed up to 20 min prior to the VT. There was a non-significant trend to higher incidence of premature ventricular complexes (PVCs) before VT compared to control recordings. The patterns of the ventricular arrhythmias were highly heterogeneous among different patients and even within the same patient. Analysis of the changes of heart rate and heart rate variability may have predictive value about the onset of VT in selected patients. The patterns of ventricular arrhythmia could not be used to predict onset of VT in this group of patients.
Arrhythmia Secondary to Cold Water Submersion during Helicopter Underwater Escape Training.
Kaur, Paven P; Drummond, Sarah E; Furyk, Jeremy
2016-02-01
A 32-year-old, fit and healthy, Caucasian male presented with a less than 24-hour history of palpitations with the onset following participation in helicopter underwater escape training (HUET). He reported no chest pain, shortness of breath, syncope, or pre-syncope symptoms. On examination, an irregularly irregular pulse was noted at a rate of 120 beats per minute with a blood pressure of 132/84. There was no evidence of congestive cardiac failure. The electrocardiogram (ECG) demonstrated atrial fibrillation at 97 beats per minute with a normal axis, normal QRS complexes, and a QTc of 399 ms. Bloods were all within normal limits and a chest x-ray showed no abnormality. The patient was loaded with amiodarone and reverted to sinus rhythm with a normal post-reversion ECG. Five years on, following further HUET, the patient presented with an identical presentation. His ECG showed fast atrial fibrillation at a rate of 115 beats per minute. On this occasion, he was sedated and Direct Current cardioverted with reversal to sinus rhythm after one shock. It was felt that the precipitating factor for this patient's atrial fibrillation, in both cases, was HUET. The case discussed describes a previously fit and well subject who developed a sustained arrhythmia secondary to cold water submersion. Evidence suggests water submersion can provoke cardiac arrhythmias via the suggested theory of "autonomic conflict." It has been proposed that a number of unexplained deaths related to water submersion may be secondary to arrhythmogenic syncope.
The Association between Prenatal Cocaine Exposure and Physiological Regulation at 13 Months of Age
ERIC Educational Resources Information Center
Schuetze, Pamela; Eiden, Rina D.; Danielewicz, Susan
2009-01-01
Background: This study examined the association between prenatal cocaine exposure (PCE) and autonomic regulation at 13 months of age. Methods: Measures of respiratory sinus arrhythmia (RSA) were obtained from 156 (79 exposed, and 77 nonexposed) infants during baseline and during tasks designed to elicit positive (PA) and negative affect (NA).…
Physiological Regulation and Fearfulness as Predictors of Young Children's Empathy-Related Reactions
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Liew, Jeffrey; Eisenberg, Nancy; Spinrad, Tracy L.; Eggum, Natalie D.; Haugen, R. G.; Kupfer, Anne; Reiser, Mark R.; Smith, Cynthia L.; Lemery-Chalfant, Kathryn; Baham, Melinda E.
2011-01-01
Indices of physiological regulation (i.e., resting respiratory sinus arrhythmia [RSA] and RSA suppression) and observed fearfulness were tested as predictors of empathy-related reactions to an unfamiliar person's simulated distress within and across 18 (T1, N = 247) and 30 (T2, N = 216) months of age. Controlling for T1 helping, high RSA…
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Hinnant, James Benjamin; El-Sheikh, Mona
2009-01-01
We examined associations between basal respiratory sinus arrhythmia (RSA) in conjunction with RSA regulation with the hypothesis that their interaction would explain unique variability in children's prospective adjustment 2 years later. Participants were 176 children (98 girls; 78 boys) in middle childhood. RSA regulation was assessed through…
Physiological Response to Social Evaluative Threat in Adolescents with Autism Spectrum Disorder
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Edmiston, E. Kale; Jones, Robin M.; Corbett, Blythe A.
2016-01-01
The Trier Social Stress Test (TSST) was employed to study response to social evaluative threat in male adolescents with Autism Spectrum Disorder (ASD, n = 21) and typical development (n = 13). Participants wore a mobile electrocardiogram to collect heart rate data. There were significant group effects on respiratory sinus arrhythmia (RSA), a…
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Blandon, Alysia Y.; Calkins, Susan D.; Keane, Susan P.; O'Brien, Marion
2008-01-01
Trajectories of emotion regulation processes were examined in a community sample of 269 children across the ages of 4 to 7 using hierarchical linear modeling. Maternal depressive symptomatology (Symptom Checklist-90) and children's physiological reactivity (respiratory sinus arrhythmia [RSA]) and vagal regulation ([delta]RSA) were explored as…
Resting RSA Is Associated with Natural and Self-Regulated Responses to Negative Emotional Stimuli
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Demaree, Heath A.; Robinson, Jennifer L.; Everhart, D. Erik; Schmeichel, Brandon J.
2004-01-01
Resting respiratory sinus arrhythmia (RSA) was assessed among 111 adult participants. These individuals were then asked to watch a positive or negative affective film in either a natural manner or while exaggerating their facial response. Facial reactions to the film were video-recorded and subsequently rated in terms of facial affect.…
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Ravaja, Niklas; Kallinen, Kari; Saari, Timo; Keltikangas-Jarvinen, Liisa
2004-01-01
The authors examined the effects of suboptimally presented facial expressions on emotional and attentional responses and memory among 39 young adults viewing video (business news) messages from a small screen. Facial electromyography (EMG) and respiratory sinus arrhythmia were used as physiological measures of emotion and attention, respectively.…
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Bal, Elgiz; Harden, Emily; Lamb, Damon; Van Hecke, Amy Vaughan; Denver, John W.; Porges, Stephen W.
2010-01-01
Respiratory Sinus Arrhythmia (RSA), heart rate, and accuracy and latency of emotion recognition were evaluated in children with autism spectrum disorders (ASD) and typically developing children while viewing videos of faces slowly transitioning from a neutral expression to one of six basic emotions (e.g., anger, disgust, fear, happiness, sadness,…
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Van Hecke, Amy Vaughan; Lebow, Jocelyn; Bal, Elgiz; Lamb, Damon; Harden, Emily; Kramer, Alexis; Denver, John; Bazhenova, Olga; Porges, Stephen W.
2009-01-01
Few studies have examined whether familiarity of partner affects social responses in children with autism. This study investigated heart rate regulation (respiratory sinus arrhythmia [RSA]: The myelinated vagus nerve's regulation of heart rate) and temporal-parietal electroencephalogram (EEG) activity while nineteen 8- to 12-year-old children with…
Marital Conflict, Allostatic Load, and the Development of Children's Fluid Cognitive Performance
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Hinnant, J. Benjamin; El-Sheikh, Mona; Keiley, Margaret; Buckhalt, Joseph A.
2013-01-01
Relations between marital conflict, children's respiratory sinus arrhythmia (RSA), and fluid cognitive performance were examined over 3 years to assess allostatic processes. Participants were 251 children reporting on marital conflict, baseline RSA, and RSA reactivity (RSA-R) to a lab challenge were recorded, and fluid cognitive performance…
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Watson, Linda R.; Roberts, Jane E.; Baranek, Grace T.; Mandulak, Kerry C.; Dalton, Jennifer C.
2012-01-01
Young boys with autism were compared to typically developing boys on responses to nonsocial and child-directed speech (CDS) stimuli. Behavioral (looking) and physiological (heart rate and respiratory sinus arrhythmia) measures were collected. Boys with autism looked equally as much as chronological age-matched peers at nonsocial stimuli, but less…
Electrocardiographic characteristics of atrioventricular block induced by tilt testing.
Zyśko, Dorota; Gajek, Jacek; Koźluk, Edward; Mazurek, Walentyna
2009-02-01
The electrocardiographic (ECG) characteristics of atrioventricular (AV) block during reflex syncope may be unique due to the presence of hypervagotonia. The aim of the present study was to define the ECG characteristics of the AV block induced by neurocardiogenic reflex provoked by tilt testing (TT). A series of 31 patients with presumed vasovagal syncope and AV block provoked by TT was studied. The duration of PP and PR interval, AV block grade and type, concomitant arrhythmias, and timing of the AV block occurrence were assessed. The AV block occurred at TT termination in 26 patients, in the recovery in 4 patients, and in both periods in 1 patient. Atrioventricular block was preceded by sinus slowing, and sinus rhythm during AV block was slow and instable. Mobitz I, 2:1 second-degree AV block, and advanced second-degree AV block were recognized in 35.5, 48.4, and 67.8% of patients, respectively. Third-degree AV block was diagnosed in 41.9% of patients. Twenty-one patients had at least two AV block forms. The most prevalent concomitant arrhythmia was junctional escape rhythm (61.3%). (i) The occurrence of the AV block during neurocardiogenic reaction induced by TT is always preceded by sinus rhythm slowing and usually by PR interval prolongation. (ii) The AV block provoked by TT usually occurs at TT termination, but may occur even in the recovery period in a supine position. Sometimes the AV block may be present both at TT termination and during the recovery period.
Zyśko, Dorota; Gajek, Jacek; Mazurek, Walentyna
2005-02-01
The inflammatory process plays important role in pathogenesis of some cardiovascular diseases. Atrial fibrillation is atrial arrhythmia with rapid, asynchronous activation of atrial myocytes. The inflammatory process can be responsible for atrial electrical and anatomical remodeling and therefore shifts towards arrhythmia persistence. The presence of systemic inflammation may be assessed by means of C-reactive protein (CRP) measurement. Maximal concentration of CRP coincidences with the peak of paroxysmal atrial fibrillation occurrence in patients after cardiac surgery. In patients with sinus rhythm the concentration of CRP is a risk factor for this arrhythmia in long-term follow-up. In patients with atrial fibrillation mean CRP concentration is 2-fold higher comparing to control group. CRP concentration is higher in patients with chronic than paroxysmal form of this arrhythmia. High CRP level predicts worse results of direct current cardioversion and more frequent paroxysms of atrial fibrillation during follow-up. Besides of, the patients with echocardiographic signs of thromboembolic risk have higher CRP levels than control subjects. There is no data about the influence of anti-inflammatory therapy on atrial fibrillation or its recurrences.
Anomalous origin of right coronary artery from left coronary sinus.
Hamzeh, Gadah; Crespo, Alex; Estarán, Rafael; Rodríguez, Miguel A; Voces, Roberto; Aramendi, José I
2008-08-01
Anomalous aortic origin of the coronary arteries is uncommon but clinically significant. Manifestations vary from asymptomatic patients to those who present with angina pectoris, myocardial infarction, heart failure, syncope, arrhythmias, and sudden death. We describe 4 patients, aged 34 to 59 years, who were diagnosed with right coronary artery arising from the left sinus of Valsalva, confirmed by coronary angiography, which was surgically repaired. Three patients presented dyspnea and angina, and one with acute myocardial infarction. At operation, the right coronary artery was dissected at the take-off from the intramural course, and reimplanted into the right sinus of Valsalva. There was no mortality. One patient had associated coronary artery disease that required stent placement postoperatively. This reimplantation technique provides a good physiological and anatomical repair, eliminates a slit-like ostium, avoids compression of the coronary artery between the aorta and the pulmonary artery, and gives superior results to coronary artery bypass grafting or the unroofing technique.
Dijkman, B; Wellens, H J
2001-09-01
The 7250 Jewel AF Medtronic model of ICD is the first implantable device in which both therapies for atrial arrhythmias and pacing algorithms for atrial arrhythmia prevention are available. Feasibility of that extensive atrial arrhythmia management requires correct and synergic functioning of different algorithms to control arrhythmias. The ability of the new pacing algorithms to stabilize the atrial rate following termination of treated atrial arrhythmias was evaluated in the marker channel registration of 600 spontaneously occurring episodes in 15 patients with the Jewel AF. All patients (55+/-15 years) had structural heart disease and documented atrial and ventricular arrhythmias. Dual chamber rate stabilization pacing was present in 245 (41 %) of episodes following arrhythmia termination and was a part of the mode switching operation during which pacing was provided in the dynamic DDI mode. This algorithm could function as the atrial rate stabilization pacing only when there was a slow spontaneous atrial rhythm or in presence of atrial premature beats conducted to the ventricles with a normal AV time. In case of atrial premature beats with delayed or absent conduction to the ventricles and in case of ventricular premature beats, the algorithm stabilized the ventricular rate. The rate stabilization pacing in DDI mode during sinus rhythm following atrial arrhythmia termination was often extended in time due to the device-based definition of arrhythmia termination. This was also the case in patients, in whom the DDD mode with true atrial rate stabilization algorithm was programmed. The rate stabilization algorithms in the Jewel AF applied after atrial arrhythmia termination provide pacing that is not based on the timing of atrial events. Only under certain circumstances the algorithm can function as atrial rate stabilization pacing. Adjustments in availability and functioning of the rate stabilization algorithms might be of benefit for the clinical performance of pacing as part of device therapy for atrial arrhythmias.
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Moore, Ginger A.; Hill-Soderlund, Ashley L.; Propper, Cathi B.; Calkins, Susan D.; Mills-Koonce, W. Roger.; Cox, Martha J.
2009-01-01
Parents' physiological regulation may support infants' regulation. Mothers (N=152) and 6-month-old male and female infants were observed in normal and disrupted social interaction. Affect was coded at 1-s intervals and vagal tone measured as respiratory sinus arrhythmia (RSA). Maternal sensitivity was assessed in free play. Mothers and infants…
Bogers, A.J.J.C.; Kik, Ch.; de Jong, P.L.; Meijboom, F.J.
2008-01-01
Surgical ablation for atrial arrhythmias at conversion of atriopulmonary or ventriculopulmonary Fontan to a total cavopulmonary connection is feasible with recovery of both sinus rhythm and atrial transport function. Recovery of the patient’s physical condition may take up to a year. (Neth Heart J 2008;16:170-2.18566699) PMID:18566699
ERIC Educational Resources Information Center
Schuetze, Pamela; Eiden, Rina D.; Edwards, Ellen P.
2009-01-01
This study examined the association between prenatal exposure to cocaine and physiological regulation across the first 7 months of age. Measures of respiratory sinus arrhythmia (RSA) were obtained from 169 (82 cocaine-exposed and 87 nonexposed) infants during baseline periods at 1 month and 7 months of age and during tasks designed to elicit…
ERIC Educational Resources Information Center
Obradovic, Jelena; Bush, Nicole R.; Stamperdahl, Juliet; Adler, Nancy E.; Boyce, W. Thomas
2010-01-01
This study examined the direct and interactive effects of stress reactivity and family adversity on socioemotional and cognitive development in three hundred and thirty-eight 5- to 6-year-old children. Neurobiological stress reactivity was measured as respiratory sinus arrhythmia and salivary cortisol responses to social, cognitive, sensory, and…
ERIC Educational Resources Information Center
Taylor, Zoe E.; Eisenberg, Nancy; Spinrad, Tracy L.
2015-01-01
The goal of this study was to examine physiological and environmental predictors of children's sympathy (an emotional response consisting of feelings of concern or sorrow for others who are distressed or in need) and whether temperamental effortful control mediated these relations. Specifically, in a study of 192 children (23% Hispanic; 54%…
ERIC Educational Resources Information Center
Miller, Jonas G.; Nuselovici, Jacob N.; Hastings, Paul D.
2016-01-01
How does empathic physiology unfold as a dynamic process, and which aspect of empathy predicts children's kindness? In response to empathy induction videos, 4- to 6-year-old children (N = 180) showed an average pattern of dynamic respiratory sinus arrhythmia (RSA) change characterized by early RSA suppression, followed by RSA recovery, and modest…
Ritz, Thomas; Bosquet Enlow, Michelle; Schulz, Stefan M.; Kitts, Robert; Staudenmayer, John; Wright, Rosalind J.
2012-01-01
Respiratory sinus arrhythmia (RSA) is related to cardiac vagal outflow and the respiratory pattern. Prior infant studies have not systematically examined respiration rate and tidal volume influences on infant RSA or the extent to which infants' breathing is too fast to extract a valid RSA. We therefore monitored cardiac activity, respiration, and physical activity in 23 six-month old infants during a standardized laboratory stressor protocol. On average, 12.6% (range 0–58.2%) of analyzed breaths were too short for RSA extraction. Higher respiration rate was associated with lower RSA amplitude in most infants, and lower tidal volume was associated with lower RSA amplitude in some infants. RSA amplitude corrected for respiration rate and tidal volume influences showed theoretically expected strong reductions during stress, whereas performance of uncorrected RSA was less consistent. We conclude that stress-induced changes of peak-valley RSA and effects of variations in breathing patterns on RSA can be determined for a representative percentage of infant breaths. As expected, breathing substantially affects infant RSA and needs to be considered in studies of infant psychophysiology. PMID:23300753
The effects of respiratory sinus arrhythmia on anger reactivity and persistence in major depression.
Ellis, Alissa J; Shumake, Jason; Beevers, Christopher G
2016-10-01
The experience of anger during a depressive episode has recently been identified as a poor prognostic indicator of illness course. Given the clinical implications of anger in major depressive disorder (MDD), understanding the mechanisms involved in anger reactivity and persistence is critical for improved intervention. Biological processes involved in emotion regulation during stress, such as respiratory sinus arrhythmia (RSA), may play a role in maintaining negative moods. Clinically depressed (MDD; n = 49) and nondepressed (non-MDD; n = 50) individuals were challenged with a stressful computer task shown to increase anger, while RSA (high frequency range 0.15-0.4 Hz) was collected. RSA predicted future anger, but was unrelated to current anger. That is, across participants, low baseline RSA predicted anger reactivity during the task, and in depressed individuals, those with low RSA during the task had a greater likelihood of anger persistence during a recovery period. These results suggest that low RSA may be a psychophysiological process involved in anger regulation in depression. Low RSA may contribute to sustained illness course by diminishing the repair of angry moods. © 2016 Society for Psychophysiological Research.
Zhang, Hui; Wang, Zhenhong; You, Xuqun; Lü, Wei; Luo, Yun
2015-09-01
The aim of the current study was to examine the direct and interactive effects of two types of narcissism (overt and covert) and respiratory sinus arrhythmia (RSA) reactivity on emotion regulation difficulties in 227 undergraduate students. Overt and covert narcissism and emotion regulation difficulties were assessed with self-report measures (narcissistic personality inventory (NPI)-16, hypersensitive narcissism scale (HSNS), and difficulties in emotion regulation scale (DERS)), and physiological data were measured during the baseline, stress (a public-speaking task), and recovery periods in the laboratory. Results indicated that overt narcissism was negatively related to a lack of emotional awareness and emotional clarity, whereas covert narcissism was positively related to overall emotion regulation difficulties, nonacceptance of emotional responses, impulse control difficulties, limited access to emotion regulation strategies, and a lack of emotional clarity. RSA reactivity in response to a mock job interview moderated the associations between covert narcissism (as a predictor) and overall emotion regulation difficulties and impulse control difficulties (as outcomes). This finding showed that a greater stress-induced RSA decrease may serve as a protective factor and ameliorate the effect of covert narcissism on individuals' emotion regulation difficulties. Copyright © 2015 Elsevier B.V. All rights reserved.
Crystal, Sarah I.; Ahles, Joshua J.; Crowell, Sheila E.
2015-01-01
Polyvagal theory suggests that parasympathetic regulation of cardiac function, indexed by resting respiratory sinus arrhythmia (RSA), may be a marker of emotion regulatory capacity and associated with youth psychopathology. Contemporary models of psychopathology suggest that the effects of biological vulnerability may be moderated by developmental context. The aim of the present study was to examine whether parenting, particularly parental responses to youth’s negative emotions, moderated the effects of resting RSA on depressive symptoms among early adolescents. We examined resting RSA, depressive symptoms, and parental responses to youth negative emotions among 120 adolescents aged 11–14 years (M = 12.86, SD = .85; 52.5% female). Resting RSA and lack of supportive parenting interacted to predict youth depressive symptoms, such that low resting RSA predicted more depressive symptoms only in the context of low levels of supportive parental responses to youth’s negative emotions. By contrast, high resting RSA buffered the effects of low supportive parenting on youth depressive symptoms. These findings highlight the importance of understanding joint contributions of biological vulnerability and developmental context on youth depression outcomes. PMID:26290213
LeMoult, Joelle; Yoon, K. Lira; Joormann, Jutta
2015-01-01
Difficulty regulating emotions following stressful events is a hallmark of Major Depressive Disorder (MDD). Although individuals’ ability to regulate their emotions is believed to have direct consequences for both emotional and physical wellbeing, few studies have examined the cardiovascular effects of different emotion regulation strategies in MDD. To the best of our knowledge, the current study is the first to examine the effects of two emotion regulation strategies, cognitive distraction and rumination, on both self-reported sadness and respiratory sinus arrhythmia (RSA) in individuals with MDD and healthy controls (CTLs). Following a forced-failure stressor, participants were randomly assigned to a rumination or cognitive distraction condition. As expected, rumination increased sadness and triggered RSA withdrawal for both MDDs and CTLs. Interestingly, although cognitive distraction reduced sadness, it also triggered RSA withdrawal. Moreover, cognitive distraction was associated with greater RSA withdrawal for MDDs than CTLs. Thus, although depressed individuals are able to use cognitive distraction to emotionally recover from stress, it may be associated with greater cognitive effort. Adding low-cost physiological measures such as RSA into assessments has the potential to offer new and important information about the effects of emotion regulation on mental and physiological health. PMID:27199505
Hegarty-Craver, Meghan; Gilchrist, Kristin H; Propper, Cathi B; Lewis, Gregory F; DeFilipp, Samuel J; Coffman, Jennifer L; Willoughby, Michael T
2017-08-08
Respiratory sinus arrhythmia (RSA) is a quantitative metric that reflects autonomic nervous system regulation and provides a physiological marker of attentional engagement that supports cognitive and affective regulatory processes. RSA can be added to executive function (EF) assessments with minimal participant burden because of the commercial availability of lightweight, wearable electrocardiogram (ECG) sensors. However, the inclusion of RSA data in large data collection efforts has been hindered by the time-intensive processing of RSA. In this study we evaluated the performance of an automated RSA-scoring method in the context of an EF study in preschool-aged children. The absolute differences in RSA across both scoring methods were small (mean RSA differences = -0.02-0.10), with little to no evidence of bias for the automated relative to the hand-scoring approach. Moreover, the relative rank-ordering of RSA across both scoring methods was strong (rs = .96-.99). Reliable changes in RSA from baseline to the EF task were highly similar across both scoring methods (96%-100% absolute agreement; Kappa = .83-1.0). On the basis of these findings, the automated RSA algorithm appears to be a suitable substitute for hand-scoring in the context of EF assessment.
Zhang, Hui; Spinrad, Tracy L; Eisenberg, Nancy; Luo, Yun; Wang, Zhenhong
2017-10-01
The aim of the current study was to address the potential moderating roles of respiratory sinus arrhythmia (RSA; baseline and suppression) and participant sex in the relation between parents' marital conflict and young adults' internet addiction. Participants included 105 (65 men) Chinese young adults who reported on their internet addiction and their parents' marital conflict. Marital conflict interacted with RSA suppression to predict internet addiction. Specifically, high RSA suppression was associated with low internet addiction, regardless of parental marital conflict; however, for participants with low RSA suppression, a positive relation between marital conflict and internet addiction was found. Internet addiction also was predicted by a significant three-way interaction among baseline RSA, marital conflict, and participant sex. Specifically, for men, marital conflict positively predicted internet addiction under conditions of low (but not high) baseline RSA. For women, marital conflict positively predicted internet addiction under conditions of high (but not low) baseline RSA. Findings highlight the importance of simultaneous consideration of physiological factors, in conjunction with family factors, in the prediction of young adults' internet addiction. Copyright © 2017 Elsevier B.V. All rights reserved.
Lynch, Michael; Manly, Jody Todd; Cicchetti, Dante
2015-11-01
Physiological response to stress has been linked to a variety of healthy and pathological conditions. The current study conducted a multilevel examination of interactions among environmental toxins (i.e., neighborhood crime and child maltreatment) and specific genetic polymorphisms of the endothelial nitric oxide synthase gene (eNOS) and GABA(A) receptor subunit alpha-6 gene (GABRA6). One hundred eighty-six children were recruited at age 4. The presence or absence of child maltreatment as well as the amount of crime that occurred in their neighborhood during the previous year were determined at that time. At age 9, the children were brought to the lab, where their physiological response to a cognitive challenge (i.e., change in the amplitude of the respiratory sinus arrhythmia) was assessed and DNA samples were collected for subsequent genotyping. The results confirmed that complex Gene × Gene, Environment × Environment, and Gene × Environment interactions were associated with different patterns of respiratory sinus arrhythmia reactivity. The implications for future research and evidence-based intervention are discussed.
Panaite, Vanessa; Hindash, Alexandra Cowden; Bylsma, Lauren M.; Small, Brent J.; Salomon, Kristen; Rottenberg, Jonathan
2015-01-01
Respiratory sinus arrhythmia (RSA) reactivity, an index of cardiac vagal tone, has been linked to self-regulation and the severity and course of depression (Rottenberg, 2007). Although initial data supports the proposition that RSA withdrawal during a sad film is a specific predictor of depression course (Fraguas, 2007; Rottenberg, 2005), the robustness and specificity of this finding are unclear. To provide a stronger test, RSA reactivity to three emotion films (happy, sad, fear) and to a more robust stressor, a speech task, were examined in currently depressed individuals (n = 37), who were assessed for their degree of symptomatic improvement over 30 weeks. Robust RSA reactivity to the sad film uniquely predicted overall symptom improvement over 30 weeks. RSA reactivity to both sad and stressful stimuli predicted the speed and maintenance of symptomatic improvement. The current analyses provide the most robust support to date that RSA withdrawal to sad stimuli (but not stressful) has specificity in predicting the overall symptomatic improvement. In contrast, RSA reactivity to negative stimuli (both sad and stressful) predicted the trajectory of depression course. Patients’ engagement with sad stimuli may be an important sign to attend to in therapeutic settings. PMID:26681648
Estimation of 3-D conduction velocity vector fields from cardiac mapping data.
Barnette, A R; Bayly, P V; Zhang, S; Walcott, G P; Ideker, R E; Smith, W M
2000-08-01
A method to estimate three-dimensional (3-D) conduction velocity vector fields in cardiac tissue is presented. The speed and direction of propagation are found from polynomial "surfaces" fitted to space-time (x, y, z, t) coordinates of cardiac activity. The technique is applied to sinus rhythm and paced rhythm mapped with plunge needles at 396-466 sites in the canine myocardium. The method was validated on simulated 3-D plane and spherical waves. For simulated data, conduction velocities were estimated with an accuracy of 1%-2%. In experimental data, estimates of conduction speeds during paced rhythm were slower than those found during normal sinus rhythm. Vector directions were also found to differ between different types of beats. The technique was able to distinguish between premature ventricular contractions and sinus beats and between sinus and paced beats. The proposed approach to computing velocity vector fields provides an automated, physiological, and quantitative description of local electrical activity in 3-D tissue. This method may provide insight into abnormal conduction associated with fatal ventricular arrhythmias.
Reithmann, Christopher; Fiek, Michael
2018-01-01
Ventricular arrhythmias (VAs) from the left ventricular outflow tract (LVOT) can have multiple exits exhibiting divergent ECG features. In a series of 131 patients with VAs with LVOT origin, 10 patients presented with divergent QRS morphologies. Multisite endo- and epicardial mapping of different exit sites was performed. The earliest ventricular activity of 23 LVOT VAs in 10 patients was detected in the endocardium of the LV in 7 patients, the aortic sinuses of Valsalva (SoV) in 3 patients, the distal coronary sinus in 6 patients, the anterior interventricular vein in 3 patients, and the posterior right ventricular outflow tract (RVOT) in 4 patients. Simultaneous elimination of two divergent QRS morphologies of LVOT VAs by ablation from a single site was achieved in 5 patients (aorto-mitral continuity in 3 patients, SoV and RVOT in each 1 patient) using a mean maximum ablation energy of 46 ± 5 W. Sequential ablation from two or three different sites, including trans-pericardial and distal coronary sinus ablation in each 2 patients, led to elimination of the divergent VA QRS morphologies in the other 5 patients. During the follow-up of 28 ± 29 months, 4 of the 10 patients had recurrence of at least one LVOT VA. A 43-year-old patient with muscular dystrophy Curschmann-Steinert had recurrence of sustained LVOT VTs and died of sudden cardiac death. Multisite mapping of different exit sites of LVOT VAs can guide ablation of intramural foci but the recurrence rate after initially successful ablation was high.
ERIC Educational Resources Information Center
Propper, Cathi; Moore, Ginger A.; Mills-Koonce, W. Roger; Halpern, Carolyn Tucker; Hill-Soderlund, Ashley L.; Calkins, Susan D.; Carbone, Mary Anna; Cox, Martha
2008-01-01
This study investigated dopamine receptor genes ("DRD2" and "DRD4") and maternal sensitivity as predictors of infant respiratory sinus arrhythmia (RSA) and RSA reactivity, purported indices of vagal tone and vagal regulation, in a challenge task at 3, 6, and 12 months in 173 infant-mother dyads. Hierarchical linear modeling (HLM) revealed that at…
Campbell, Hamish A; Leite, Cleo A C; Wang, Tobias; Skals, Marianne; Abe, Augusto S; Egginton, Stuart; Rantin, F Tadeu; Bishop, Charles M; Taylor, Edwin W
2006-07-01
Autonomic control of heart rate variability and the central location of vagal preganglionic neurones (VPN) were examined in the rattlesnake (Crotalus durissus terrificus), in order to determine whether respiratory sinus arrhythmia (RSA) occurred in a similar manner to that described for mammals. Resting ECG signals were recorded in undisturbed snakes using miniature datalogging devices, and the presence of oscillations in heart rate (fh) was assessed by power spectral analysis (PSA). This mathematical technique provides a graphical output that enables the estimation of cardiac autonomic control by measuring periodic changes in the heart beat interval. At fh above 19 min(-1) spectra were mainly characterised by low frequency components, reflecting mainly adrenergic tonus on the heart. By contrast, at fh below 19 min(-1) spectra typically contained high frequency components, demonstrated to be cholinergic in origin. Snakes with a fh >19 min(-1) may therefore have insufficient cholinergic tonus and/or too high an adrenergic tonus acting upon the heart for respiratory sinus arrhythmia (RSA) to develop. A parallel study monitored fh simultaneously with the intraperitoneal pressures associated with lung inflation. Snakes with a fh<19 min(-1) exhibited a high frequency (HF) peak in the power spectrum, which correlated with ventilation rate (fv). Adrenergic blockade by propranolol infusion increased the variability of the ventilation cycle, and the oscillatory component of the fh spectrum broadened accordingly. Infusion of atropine to effect cholinergic blockade abolished this HF component, confirming a role for vagal control of the heart in matching fh and fv in the rattlesnake. A neuroanatomical study of the brainstem revealed two locations for vagal preganglionic neurones (VPN). This is consistent with the suggestion that generation of ventilatory components in the heart rate variability (HRV) signal are dependent on spatially distinct loci for cardiac VPN. Therefore, this study has demonstrated the presence of RSA in the HRV signal and a dual location for VPN in the rattlesnake. We suggest there to be a causal relationship between these two observations.
Albarado-Ibañez, Alondra; Avelino-Cruz, José Everardo; Velasco, Myrian; Torres-Jácome, Julián; Hiriart, Marcia
2013-01-01
In the last ten years, the incidences of metabolic syndrome and supraventricular arrhythmias have greatly increased. The metabolic syndrome is a cluster of alterations, which include obesity, hypertension, hypertriglyceridemia, glucose intolerance and insulin resistance, that increase the risk of developing, among others, atrial and nodal arrhythmias. The aim of this study is to demonstrate that metabolic syndrome induces electrical remodeling of the sinus node and produces arrhythmias. We induced metabolic syndrome in 2-month-old male Wistar rats by administering 20% sucrose in the drinking water. Eight weeks later, the rats were anesthetized and the electrocardiogram was recorded, revealing the presence of arrhythmias only in treated rats. Using conventional microelectrode and voltage clamp techniques, we analyzed the electrical activity of the sinoatrial node. We observed that in the sinoatrial node of “metabolic syndrome rats”, compared to controls, the spontaneous firing of all cells decreased, while the slope of the diastolic depolarization increased only in latent pacemaker cells. Accordingly, the pacemaker currents If and Ist increased. Furthermore, histological analysis showed a large amount of fat surrounding nodal cardiomyocytes and a rise in the sympathetic innervation. Finally, Poincaré plot denoted irregularity in the R-R and P-P ECG intervals, in agreement with the variability of nodal firing potential recorded in metabolic syndrome rats. We conclude that metabolic syndrome produces a dysfunction SA node by disrupting normal architecture and the electrical activity, which could explain the onset of arrhythmias in rats. PMID:24250786
Albarado-Ibañez, Alondra; Avelino-Cruz, José Everardo; Velasco, Myrian; Torres-Jácome, Julián; Hiriart, Marcia
2013-01-01
In the last ten years, the incidences of metabolic syndrome and supraventricular arrhythmias have greatly increased. The metabolic syndrome is a cluster of alterations, which include obesity, hypertension, hypertriglyceridemia, glucose intolerance and insulin resistance, that increase the risk of developing, among others, atrial and nodal arrhythmias. The aim of this study is to demonstrate that metabolic syndrome induces electrical remodeling of the sinus node and produces arrhythmias. We induced metabolic syndrome in 2-month-old male Wistar rats by administering 20% sucrose in the drinking water. Eight weeks later, the rats were anesthetized and the electrocardiogram was recorded, revealing the presence of arrhythmias only in treated rats. Using conventional microelectrode and voltage clamp techniques, we analyzed the electrical activity of the sinoatrial node. We observed that in the sinoatrial node of "metabolic syndrome rats", compared to controls, the spontaneous firing of all cells decreased, while the slope of the diastolic depolarization increased only in latent pacemaker cells. Accordingly, the pacemaker currents If and Ist increased. Furthermore, histological analysis showed a large amount of fat surrounding nodal cardiomyocytes and a rise in the sympathetic innervation. Finally, Poincaré plot denoted irregularity in the R-R and P-P ECG intervals, in agreement with the variability of nodal firing potential recorded in metabolic syndrome rats. We conclude that metabolic syndrome produces a dysfunction SA node by disrupting normal architecture and the electrical activity, which could explain the onset of arrhythmias in rats.
Surgical outcome of Fontan conversion and arrhythmia surgery: Need a pacemaker?
Terada, Takafumi; Sakurai, Hajime; Nonaka, Toshimichi; Sakurai, Takahisa; Sugiura, Junya; Taneichi, Tetsuyoshi; Ohtsuka, Ryohei
2014-07-01
Atrial tachyarrhythmias are frequent complications in the late period after the Fontan procedure, and important risk factors for a poor prognosis. The impact of Fontan conversion and arrhythmia surgery in failed Fontan patients has been described in many reports. We evaluated our experience with Fontan conversion procedures, concomitant arrhythmia surgery, and pacemaker implantation. We reviewed the hospital records of 25 consecutive patients who underwent a Fontan conversion procedure from January 2004 to March 2012. Twenty-four patients had arrhythmia surgery using cryoablation and radiofrequency ablation at the time of conversion. A bilateral atrial maze procedure was performed in 6 patients, right-side maze in 15, and isthmus block in 3. Three patients with a diagnosis of corrected transposition of the great arteries underwent simultaneous pacemaker implantation electively. There was no early death and one late death during a mean follow-up period of 21.2 months. Three tachyarrhythmia recurrences developed, and there were 4 occurrences of sinus bradycardia. Five of these patients required postoperative pacemaker implantation. The mid-term results of Fontan conversion and arrhythmia surgery in our institute were satisfactory. The occurrence of unexpected postoperative pacemaker requirement was high in the patients who underwent a right atrial or bilateral atrial maze procedure. Pacemaker or lead implantation is recommended for patients planned to undergo a right-side or full maze procedure. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
ECG signal quality during arrhythmia and its application to false alarm reduction.
Behar, Joachim; Oster, Julien; Li, Qiao; Clifford, Gari D
2013-06-01
An automated algorithm to assess electrocardiogram (ECG) quality for both normal and abnormal rhythms is presented for false arrhythmia alarm suppression of intensive care unit (ICU) monitors. A particular focus is given to the quality assessment of a wide variety of arrhythmias. Data from three databases were used: the Physionet Challenge 2011 dataset, the MIT-BIH arrhythmia database, and the MIMIC II database. The quality of more than 33 000 single-lead 10 s ECG segments were manually assessed and another 12 000 bad-quality single-lead ECG segments were generated using the Physionet noise stress test database. Signal quality indices (SQIs) were derived from the ECGs segments and used as the inputs to a support vector machine classifier with a Gaussian kernel. This classifier was trained to estimate the quality of an ECG segment. Classification accuracies of up to 99% on the training and test set were obtained for normal sinus rhythm and up to 95% for arrhythmias, although performance varied greatly depending on the type of rhythm. Additionally, the association between 4050 ICU alarms from the MIMIC II database and the signal quality, as evaluated by the classifier, was studied. Results suggest that the SQIs should be rhythm specific and that the classifier should be trained for each rhythm call independently. This would require a substantially increased set of labeled data in order to train an accurate algorithm.
Walden, Tedra A.; Conture, Edward G.; Erdemir, Aysu; Lambert, Warren E.; Porges, Stephen W.
2017-01-01
Purpose This study sought to determine whether respiratory sinus arrhythmia (RSA) and executive functions are associated with stuttered speech disfluencies of young children who do (CWS) and do not stutter (CWNS). Method Thirty-six young CWS and 36 CWNS were exposed to neutral, negative, and positive emotion-inducing video clips, followed by their participation in speaking tasks. During the neutral video, we measured baseline RSA, a physiological index of emotion regulation, and during video viewing and speaking, we measured RSA change from baseline, a physiological index of regulatory responses during challenge. Participants' caregivers completed the Children's Behavior Questionnaire from which a composite score of the inhibitory control and attentional focusing subscales served to index executive functioning. Results For both CWS and CWNS, greater decrease of RSA during both video viewing and speaking was associated with more stuttering. During speaking, CWS with lower executive functioning exhibited a negative association between RSA change and stuttering; conversely, CWNS with higher executive functioning exhibited a negative association between RSA change and stuttering. Conclusion Findings suggest that decreased RSA during video viewing and speaking is associated with increased stuttering and young CWS differ from CWNS in terms of how their executive functions moderate the relation between RSA change and stuttered disfluencies. PMID:28763803
Lunkenheimer, Erika; Tiberio, Stacey S.; Buss, Kristin A.; Lucas-Thompson, Rachel G.; Boker, Steven M.; Timpe, Zachary C.
2015-01-01
The coordination of physiological processes between parents and infants is thought to support behaviors critical for infant adaptation, but we know little about parent-child physiological coregulation during the preschool years. The present study examined whether time-varying changes in parent and child respiratory sinus arrhythmia (RSA) exhibited coregulation (across-person dynamics) accounting for individual differences in parent and child RSA, and whether there were differences in these parasympathetic processes by children’s externalizing problems. Mother-child dyads (N=47; Child age M=3½ years) engaged in three laboratory tasks (free play, clean up, puzzle task) for 18 min, during which RSA data were collected. Multilevel coupled autoregressive models revealed that mothers and preschoolers showed positive coregulation of RSA such that changes in mother RSA predicted changes in the same direction in child RSA and vice versa, controlling for the stability of within-person RSA over time and individual differences in overall mean RSA. However, when children’s externalizing behaviors were higher, coregulation was negative such that changes in real-time mother and child RSA showed divergence rather than positive concordance. Results suggest that mothers and preschoolers do coregulate RSA during real-time interactions, but that children’s higher externalizing behavior problems are related to disruptions in these processes. PMID:25976070
Panaite, Vanessa; Hindash, Alexandra Cowden; Bylsma, Lauren M; Small, Brent J; Salomon, Kristen; Rottenberg, Jonathan
2016-01-01
Respiratory sinus arrhythmia (RSA) reactivity, an index of cardiac vagal tone, has been linked to self-regulation and the severity and course of depression (Rottenberg, 2007). Although initial data supports the proposition that RSA withdrawal during a sad film is a specific predictor of depression course (Fraguas, 2007; Rottenberg, 2005), the robustness and specificity of this finding are unclear. To provide a stronger test, RSA reactivity to three emotion films (happy, sad, fear) and to a more robust stressor, a speech task, were examined in currently depressed individuals (n=37), who were assessed for their degree of symptomatic improvement over 30weeks. Robust RSA reactivity to the sad film uniquely predicted overall symptom improvement over 30weeks. RSA reactivity to both sad and stressful stimuli predicted the speed and maintenance of symptomatic improvement. The current analyses provide the most robust support to date that RSA withdrawal to sad stimuli (but not stressful) has specificity in predicting the overall symptomatic improvement. In contrast, RSA reactivity to negative stimuli (both sad and stressful) predicted the trajectory of depression course. Patients' engagement with sad stimuli may be an important sign to attend to in therapeutic settings. Copyright © 2015 Elsevier B.V. All rights reserved.
Microgravity alters respiratory sinus arrhythmia and short-term heart rate variability in humans
NASA Technical Reports Server (NTRS)
Migeotte, P-F; Prisk, G. Kim; Paiva, M.; West, J. B. (Principal Investigator)
2003-01-01
We studied heart rate (HR), heart rate variability (HRV), and respiratory sinus arrhythmia (RSA) in four male subjects before, during, and after 16 days of spaceflight. The electrocardiogram and respiration were recorded during two periods of 4 min controlled breathing at 7.5 and 15 breaths/min in standing and supine postures on the ground and in microgravity. Low (LF)- and high (HF)-frequency components of the short-term HRV (< or =3 min) were computed through Fourier spectral analysis of the R-R intervals. Early in microgravity, HR was decreased compared with both standing and supine positions and had returned to the supine value by the end of the flight. In microgravity, overall variability, the LF-to-HF ratio, and RSA amplitude and phase were similar to preflight supine values. Immediately postflight, HR increased by approximately 15% and remained elevated 15 days after landing. LF/HF was increased, suggesting an increased sympathetic control of HR standing. The overall variability and RSA amplitude in supine decreased postflight, suggesting that vagal tone decreased, which coupled with the decrease in RSA phase shift suggests that this was the result of an adaptation of autonomic control of HR to microgravity. In addition, these alterations persisted for at least 15 days after return to normal gravity (1G).
Holochwost, Steven J; Volpe, Vanessa V; Gueron-Sela, Noa; Propper, Cathi B; Mills-Koonce, W Roger
2018-03-13
Deficits of inhibitory control in early childhood are linked to externalizing behaviors and attention problems. While environmental factors and physiological processes are associated with its etiology, few studies have examined how these factors jointly predict inhibitory control. This study examined whether respiratory sinus arrhythmia (RSA) functioned as a mediator or moderator of both cumulative sociodemographic risk and parenting behaviors on inhibitory control during early childhood. The sample included 206 children and their biological mothers. At 24, 30, and 36 months of child age dyads participated in a series of laboratory visits in which sociodemographic, parenting, and baseline RSA (RSAB) data were collected. Inhibitory control was assessed at 36 months using a gift-wrap delay task. A series of structural equation models yielded no evidence that RSAB mediated the relations of risk or parenting and inhibitory control. RSAB moderated the effects of risk, such that high-risk children with low RSAB performed more poorly on tasks of inhibitory control, while high-risk children with high RSAB did not. These results suggest that higher levels of RSAB may mitigate the influence of environmental risk on the development of inhibitory control early childhood. © 2018 Association for Child and Adolescent Mental Health.
NASA Technical Reports Server (NTRS)
Elstad, M.; Toska, K.; Chon, K. H.; Raeder, E. A.; Cohen, R. J.
2001-01-01
1. Are arterial blood pressure fluctuations buffered or reinforced by respiratory sinus arrhythmia (RSA)? There is still considerable debate about this simple question. Different results have been obtained, triggering a discussion as to whether or not the baroreflexes are responsible for RSA. We suspected that the measurements of different aspects of arterial pressure (mean arterial pressure (MAP) and systolic pressure (SP)) can explain the conflicting results. 2. Simultaneous recordings of beat-to-beat MAP, SP, left cardiac stroke volume (SV, pulsed ultrasound Doppler), heart rate (HR) and respiration (RE) were obtained in 10 healthy young adults during spontaneous respiration. In order to eliminate HR variations at respiratory frequency we used propranolol and atropine administration in the supine and tilted positions. Respiration-synchronous variation in the recorded variables was quantified by spectral analysis of the recordings of each of these variables, and the phase relations between them were determined by cross-spectral analysis. 3. MAP fluctuations increased after removing heart rate variations in both supine and tilted position, whereas SP fluctuations decreased in the supine position and increased in the head-up tilted position. 4. RSA buffers respiration-synchronous fluctuations in MAP in both positions. However, fluctuations in SP were reinforced by RSA in the supine and buffered in the tilted position.
Lunkenheimer, Erika; Tiberio, Stacey S; Buss, Kristin A; Lucas-Thompson, Rachel G; Boker, Steven M; Timpe, Zachary C
2015-12-01
The coordination of physiological processes between parents and infants is thought to support behaviors critical for infant adaptation, but we know little about parent-child physiological coregulation during the preschool years. The present study examined whether time-varying changes in parent and child respiratory sinus arrhythmia (RSA) exhibited coregulation (across-person dynamics) accounting for individual differences in parent and child RSA, and whether there were differences in these parasympathetic processes by children's externalizing problems. Mother-child dyads (N = 47; Child age M = 3½ years) engaged in three laboratory tasks (free play, clean up, puzzle task) for 18 min, during which RSA data were collected. Multilevel coupled autoregressive models revealed that mothers and preschoolers showed positive coregulation of RSA such that changes in mother RSA predicted changes in the same direction in child RSA and vice versa, controlling for the stability of within-person RSA over time and individual differences in overall mean RSA. However, when children's externalizing behaviors were higher, coregulation was negative such that changes in real-time mother and child RSA showed divergence rather than positive concordance. Results suggest that mothers and preschoolers do coregulate RSA during real-time interactions, but that children's higher externalizing behavior problems are related to disruptions in these processes. © 2015 Wiley Periodicals, Inc.
Gray, Sarah A O; Theall, Katherine; Lipschutz, Rebecca; Drury, Stacy
2017-03-01
Respiratory sinus arrhythmia (RSA), a marker of parasympathetic activity, has been shown to moderate the relation between adversity and child behavioral outcomes; however, this work has been conducted in primarily Caucasian samples and limited in focus to family-level adversity. The current analysis extends the previous literature to examine the co-contribution of exposure to potentially traumatic events (PTEs), baseline RSA, and RSA withdrawal to internalizing and externalizing behavior in a sample of primarily African American youth ( n = 92) recruited using neighborhood mapping techniques from communities high in epidemiological indicators of adversity. Exposure to PTEs was associated with lower baseline RSA. Complex interactions were observed between sex of the child, baseline RSA and RSA withdrawal, and PTE exposure predicting to internalizing behaviors. Among girls with high (4+) levels of PTEs, high baseline RSA and RSA withdrawal predicted higher internalizing; for RSA withdrawal only, the inverse was observed for girls with low PTE exposure, for whom high RSA withdrawal predicted lower internalizing. No associations were observed from RSA to externalizing, or among boys to internalizing. Findings are consistent with distinct patterns among primarily African American samples and suggest the need for sex-specific conceptualizations of the link between environmental adversity, physiological reactivity, and internalizing behaviors.
Gray, Sarah A. O.; Theall, Katherine; Lipschutz, Rebecca; Drury, Stacy
2016-01-01
Respiratory sinus arrhythmia (RSA), a marker of parasympathetic activity, has been shown to moderate the relation between adversity and child behavioral outcomes; however, this work has been conducted in primarily Caucasian samples and limited in focus to family-level adversity. The current analysis extends the previous literature to examine the co-contribution of exposure to potentially traumatic events (PTEs), baseline RSA, and RSA withdrawal to internalizing and externalizing behavior in a sample of primarily African American youth (n = 92) recruited using neighborhood mapping techniques from communities high in epidemiological indicators of adversity. Exposure to PTEs was associated with lower baseline RSA. Complex interactions were observed between sex of the child, baseline RSA and RSA withdrawal, and PTE exposure predicting to internalizing behaviors. Among girls with high (4+) levels of PTEs, high baseline RSA and RSA withdrawal predicted higher internalizing; for RSA withdrawal only, the inverse was observed for girls with low PTE exposure, for whom high RSA withdrawal predicted lower internalizing. No associations were observed from RSA to externalizing, or among boys to internalizing. Findings are consistent with distinct patterns among primarily African American samples and suggest the need for sex-specific conceptualizations of the link between environmental adversity, physiological reactivity, and internalizing behaviors. PMID:28479668
Jones, Robin M; Walden, Tedra A; Conture, Edward G; Erdemir, Aysu; Lambert, Warren E; Porges, Stephen W
2017-08-16
This study sought to determine whether respiratory sinus arrhythmia (RSA) and executive functions are associated with stuttered speech disfluencies of young children who do (CWS) and do not stutter (CWNS). Thirty-six young CWS and 36 CWNS were exposed to neutral, negative, and positive emotion-inducing video clips, followed by their participation in speaking tasks. During the neutral video, we measured baseline RSA, a physiological index of emotion regulation, and during video viewing and speaking, we measured RSA change from baseline, a physiological index of regulatory responses during challenge. Participants' caregivers completed the Children's Behavior Questionnaire from which a composite score of the inhibitory control and attentional focusing subscales served to index executive functioning. For both CWS and CWNS, greater decrease of RSA during both video viewing and speaking was associated with more stuttering. During speaking, CWS with lower executive functioning exhibited a negative association between RSA change and stuttering; conversely, CWNS with higher executive functioning exhibited a negative association between RSA change and stuttering. Findings suggest that decreased RSA during video viewing and speaking is associated with increased stuttering and young CWS differ from CWNS in terms of how their executive functions moderate the relation between RSA change and stuttered disfluencies.
Dual chamber arrhythmia detection in the implantable cardioverter defibrillator.
Dijkman, B; Wellens, H J
2000-10-01
Dual chamber implantable cardioverter defibrillator (ICD) technology extended ICD therapy to more than termination of hemodynamically unstable ventricular tachyarrhythmias. It created the basis for dual chamber arrhythmia management in which dependable detection is important for treatment and prevention of both ventricular and atrial arrhythmias. Dual chamber detection algorithms were investigated in two Medtronic dual chamber ICDs: the 7250 Jewel AF (33 patients) and the 7271 Gem DR (31 patients). Both ICDs use the same PR Logic algorithm to interpret tachycardia as ventricular tachycardia (VT), supraventricular tachycardia (SVT), or dual (VT+ SVT). The accuracy of dual chamber detection was studied in 310 of 1,367 spontaneously occurring tachycardias in which rate criterion only was not sufficient for arrhythmia diagnosis. In 78 episodes there was a double tachycardia, in 223 episodes SVT was detected in the VT or ventricular fibrillation zone, and in 9 episodes arrhythmia was detected outside the boundaries of the PR Logic functioning. In 100% of double tachycardias the VT was correctly diagnosed and received priority treatment. SVT was seen in 59 (19%) episodes diagnosed as VT. The causes of inappropriate detection were (1) algorithm failure (inability to fulfill the PR
[The relationship of ECG and pregnancy outcome of older pregnant woman in late pregnancy].
Zhao, Xiao-Qin; Wang, Chun-Guang; Song, Yu-Xia; Jiao, Hong
2014-01-01
To observe the changes of electrocardiogram (ECG) and pregnancy outcome of the late pregnancy women. Late pregnancy women were divided into two groups by age: over 35 group and under 35 group. The incidence of abnormal electrocardiogram was recorded when the patients were subjected to routine ECG examination. Then the pregnancy, delivery outcome and if there's low birth weight newborn were recorded later. The incidence of abnormal ECG in over 35 group was significantly higher than that in under 35 group (P < 0.05). And the incidence of ST segment changes, arrhythmia in the group of former was higher than that in the group of latter (P < 0.05). Among the different type of arrhythmia, the incidence of sinus bradycardia and ventricular premature beat in the group of former were higher than those in the group of latter (P < 0.05). But the incidence of sinus tachycardia in the former group was obviously lower than that in the latter group (P < 0.05). The incidence of pregnancy loss in over 35 with abnormal ECG group was significantly higher than that in under 35 with normal or abnormal ECG groups (P < 0.05). The incidence of premature birth in over 35 with abnormal ECG group was significantly higher than that in over 35 with normal ECG group (P < 0.05). The incidence of low body weight in over 35 with abnormal ECG group was significantly higher than that in under 35 with normal ECG group (P < 0.05). The late pregnancy women with the age of over 35 are more likely to have ECG abnormalities, such as arrhythmia, myocardial ischemia and so on. The older pregnant women with abnormal ECG easily suffer from pregnancy losing, premature birth and having a low birth weight baby.
[Sinus rhythm: mechanisms and function].
Lerebours, Guy
2007-01-01
The normal cardiac rhythm originates in a specialized region of the heart, the sinus node that is part of the nodal tissue. The rhythmic, impulse initiation of sinus node pacemaker cells results from a spontaneous diastolic depolarization that is initiated immediately after repolarization of the preceding actions potential. This slow diastolic depolarisation is typical of automatic cells and essential to their function. Several currents are involved in this diastolic depolarisation: a hyperpolarization activated inward current, termed "pacemaker" I(f) current, two Ca2+ currents (a L type and a T type), a delayed K+ current and a Na/Ca exchange current. The frequency of the automatic discharge is the main determinant of heart rate. However the sinus node activity is regulated by adrenergic and cholinergic neurotransmitters. Acetylcholine provokes the hyperpolarization of pacemaker cells and decreases the speed of the spontaneous diastolic depolarisation, thus slowing the sinus rate. Catecholamines lead to sinus tachycardia by increasing the diastolic depolarisation speed. In normal conditions, the observed resting heart rate is lower than the intrinsic frequency of the sinus node due to a "predominance" of the vagal tone. Neural regulation of the heart rate aims at meeting the metabolic needs of the tissues through a varying blood flow. Differences between diurnal and nocturnal mean heart rates are accounted for by neural influences. During the night, the increased vagal tone results in decreased heart rate. The exercise-induced tachycardia results from the sympathetic stimulation. It allows more blood to reach skeletal muscles, and as a consequence an increased supply of oxygen and nutrients. Compared to the variety of clinical arrhythmias, sinus rhythm is the basis for optimal exercise capacity and quality of life.
Pérez de Prado, Armando; López-Gómez, Juan M.; Quiroga, Borja; Goicoechea, Marian; García-Prieto, Ana; Torres, Esther; Reque, Javier; Luño, José
2016-01-01
Background and objectives Supraventricular arrhythmias are associated with high morbidity and mortality. Nevertheless, this condition has received little attention in patients on hemodialysis. The objective of this study was to analyze the incidence of intradialysis supraventricular arrhythmia and its long–term prognostic value. Design, setting, participants, & measurements We designed an observational and prospective study in a cohort of patients on hemodialysis with a 10-year follow-up period. All patients were recruited for study participation and were not recruited for clinical indications. The study population comprised 77 patients (42 men and 35 women; mean age =58±15 years old) with sinus rhythm monitored using a Holter electrocardiogram over six consecutive hemodialysis sessions at recruitment. Results Hypertension was present in 68.8% of patients, and diabetes was present in 29.9% of patients. Supraventricular arrhythmias were recorded in 38 patients (49.3%); all of these were short, asymptomatic, and self-limiting. Age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08) and right atrial enlargement (hazard ratio, 4.29; 95% confidence interval, 1.30 to 14.09) were associated with supraventricular arrhythmia in the multivariate analysis. During a median follow-up of 40 months, 57 patients died, and cardiovascular disease was the main cause of death (52.6%). The variables associated with all-cause mortality in the Cox model were age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08), C-reactive protein (hazard ratio, 1.04 per 1 mg/L; 95% confidence interval, 1.00 to 1.08), and supraventricular arrhythmia (hazard ratio, 3.21; 95% confidence interval, 1.29 to 7.96). Patients with supraventricular arrhythmia also had a higher risk of nonfatal cardiovascular events (hazard ratio, 4.32; 95% confidence interval, 2.11 to 8.83) and symptomatic atrial fibrillation during follow-up (hazard ratio, 17.19; 95% confidence interval, 2.03 to 145.15). Conclusions The incidence of intradialysis supraventricular arrhythmia was high in our hemodialysis study population. Supraventricular arrhythmias were short, asymptomatic, and self-limiting, and although silent, these arrhythmias were independently associated with mortality and cardiovascular events. PMID:27697781
Verde, Eduardo; Pérez de Prado, Armando; López-Gómez, Juan M; Quiroga, Borja; Goicoechea, Marian; García-Prieto, Ana; Torres, Esther; Reque, Javier; Luño, José
2016-12-07
Supraventricular arrhythmias are associated with high morbidity and mortality. Nevertheless, this condition has received little attention in patients on hemodialysis. The objective of this study was to analyze the incidence of intradialysis supraventricular arrhythmia and its long-term prognostic value. We designed an observational and prospective study in a cohort of patients on hemodialysis with a 10-year follow-up period. All patients were recruited for study participation and were not recruited for clinical indications. The study population comprised 77 patients (42 men and 35 women; mean age =58±15 years old) with sinus rhythm monitored using a Holter electrocardiogram over six consecutive hemodialysis sessions at recruitment. Hypertension was present in 68.8% of patients, and diabetes was present in 29.9% of patients. Supraventricular arrhythmias were recorded in 38 patients (49.3%); all of these were short, asymptomatic, and self-limiting. Age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08) and right atrial enlargement (hazard ratio, 4.29; 95% confidence interval, 1.30 to 14.09) were associated with supraventricular arrhythmia in the multivariate analysis. During a median follow-up of 40 months, 57 patients died, and cardiovascular disease was the main cause of death (52.6%). The variables associated with all-cause mortality in the Cox model were age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08), C-reactive protein (hazard ratio, 1.04 per 1 mg/L; 95% confidence interval, 1.00 to 1.08), and supraventricular arrhythmia (hazard ratio, 3.21; 95% confidence interval, 1.29 to 7.96). Patients with supraventricular arrhythmia also had a higher risk of nonfatal cardiovascular events (hazard ratio, 4.32; 95% confidence interval, 2.11 to 8.83) and symptomatic atrial fibrillation during follow-up (hazard ratio, 17.19; 95% confidence interval, 2.03 to 145.15). The incidence of intradialysis supraventricular arrhythmia was high in our hemodialysis study population. Supraventricular arrhythmias were short, asymptomatic, and self-limiting, and although silent, these arrhythmias were independently associated with mortality and cardiovascular events. Copyright © 2016 by the American Society of Nephrology.
Domingo, Diana; Neco, Patricia; Fernández-Pons, Elena; Zissimopoulos, Spyros; Molina, Pilar; Olagüe, José; Suárez-Mier, M Paz; Lai, F Anthony; Gómez, Ana M; Zorio, Esther
2015-05-01
Catecholaminergic polymorphic ventricular tachycardia is a malignant disease, due to mutations in proteins controlling Ca(2+) homeostasis. While the phenotype is characterized by polymorphic ventricular arrhythmias under stress, supraventricular arrhythmias may occur and are not fully characterized. Twenty-five relatives from a Spanish family with several sudden deaths were evaluated with electrocardiogram, exercise testing, and optional epinephrine challenge. Selective RyR2 sequencing in an affected individual and cascade screening in the rest of the family was offered. The RyR2(R420Q) mutation was generated in HEK-293 cells using site-directed mutagenesis to conduct in vitro functional studies. The exercise testing unmasked catecholaminergic polymorphic ventricular tachycardia in 8 relatives (sensitivity = 89%; positive predictive value = 100%; negative predictive value = 93%), all of them carrying the heterozygous RyR2(R420Q) mutation, which was also present in the proband and a young girl without exercise testing, a 91% penetrance at the end of the follow-up. Remarkably, sinus bradycardia, atrial and junctional arrhythmias, and/or giant post-effort U-waves were identified in patients. Upon permeabilization and in intact cells, the RyR2(R420Q) expressing cells showed a smaller peak of Ca(2+) release than RyR2 wild-type cells. However, at physiologic intracellular Ca(2+) concentration, equivalent to the diastolic cytosolic concentration, the RyR2(R420Q) released more Ca(2+) and oscillated faster than RyR2 wild-type cells. The missense RyR2(R420Q) mutation was identified in the N-terminus of the RyR2 gene in this highly symptomatic family. Remarkably, this mutation is associated with sinus bradycardia, atrial and junctional arrhythmias, and giant U-waves. Collectively, functional heterologous expression studies suggest that the RyR2(R420Q) behaves as an aberrant channel, as a loss- or gain-of-function mutation depending on cytosolic intracellular Ca(2+) concentration. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.
Lasukova, T V; Krylatov, A V; Maslov, L N; Lishmanov, Iu B; Gross, G J; Podoksenov, Iu K; Podoksenov, A Iu
2004-01-01
Pretreatment with intravenous peptide delta1-opioid receptor (OR) agonist DPDPE (0.5 mg/kg) decreases the incidence of occlusion (10 min) and reperfusion (10 min) arrhythmias in rats. The agonist of delta2-OR DSLET has no effect on arrhythmias in coronary artery occlusion and reperfusion. Pretreatment with selective delta-antagonists ICI 174,864 (2.5 mg/kg) eliminates an antiarrhythmic effect of DPDPE. The addition of DPDPE to the perfusion solution in a final concentration of 0.1 mg/l and/or 0.5 mg/l fifteen min before ischemia also decreases the incidence of reperfusion arrhythmias in a concentration-dependent manner. The addition of DPDPE to the perfusion solution in a final concentration of 0.1 mg/l decreases creatine kinase levels in the coronary sinus effluent. However, DPDPE has no cardioprotective effect in a concentration of 0.5 mg/l or after intravenous administration. It is suggested that antiarrhythmic and cardioprotective effects of DPDPE during reperfusion may be due to stimulation of cardiac delta1-receptors.
Model-based imaging of cardiac electrical function in human atria
NASA Astrophysics Data System (ADS)
Modre, Robert; Tilg, Bernhard; Fischer, Gerald; Hanser, Friedrich; Messnarz, Bernd; Schocke, Michael F. H.; Kremser, Christian; Hintringer, Florian; Roithinger, Franz
2003-05-01
Noninvasive imaging of electrical function in the human atria is attained by the combination of data from electrocardiographic (ECG) mapping and magnetic resonance imaging (MRI). An anatomical computer model of the individual patient is the basis for our computer-aided diagnosis of cardiac arrhythmias. Three patients suffering from Wolff-Parkinson-White syndrome, from paroxymal atrial fibrillation, and from atrial flutter underwent an electrophysiological study. After successful treatment of the cardiac arrhythmia with invasive catheter technique, pacing protocols with stimuli at several anatomical sites (coronary sinus, left and right pulmonary vein, posterior site of the right atrium, right atrial appendage) were performed. Reconstructed activation time (AT) maps were validated with catheter-based electroanatomical data, with invasively determined pacing sites, and with pacing at anatomical markers. The individual complex anatomical model of the atria of each patient in combination with a high-quality mesh optimization enables accurate AT imaging, resulting in a localization error for the estimated pacing sites within 1 cm. Our findings may have implications for imaging of atrial activity in patients with focal arrhythmias.
Yue-Chun, Li; Jia-Feng, Lin; Jia-Xuan, Lin
2015-10-01
Electrocardiographic characteristics can be useful in differentiating between right ventricular outflow tract (RVOT) and aortic sinus cusp (ASC) ventricular arrhythmias. Ventricular arrhythmias originating from ASC, however, show preferential conduction to RVOT that may render the algorithms of electrocardiographic characteristics less reliable. Even though there are few reports describing ventricular arrhythmias with ASC origins and endocardial breakout sites of RVOT, progressive dynamic changes in QRS morphology of the ventricular arrhythmias during ablation obtained were rare.This case report describes a patient with symptomatic premature ventricular contractions of left ASC origin presenting an electrocardiogram (ECG) characteristic of right ventricular outflow tract before ablation. Pacing at right ventricular outflow tract reproduced an excellent pace map. When radiofrequency catheter ablation was applied to the right ventricular outflow tract, the QRS morphology of premature ventricular contractions progressively changed from ECG characteristics of right ventricular outflow tract origin to ECG characteristics of left ASC origin.Successful radiofrequency catheter ablation was achieved at the site of the earliest ventricular activation in the left ASC. The distance between the successful ablation site of the left ASC and the site with an excellent pace map of the RVOT was 20 mm.The ndings could be strong evidence for a preferential conduction via the myocardial bers from the ASC origin to the breakout site in the right ventricular outflow tract. This case demonstrates that ventricular arrhythmias with a single origin and exit shift may exhibit QRS morphology changes.
Reversible atrial fibrillation following Crotalinae envenomation.
Quan, Dan; Zurcher, Kenneth
2017-01-01
Cardiotoxicity is a documented complication of Crotalinae envenomation. Reported cardiac complications following snake envenomation have included acute myocardial infarction, electrocardiogram abnormalities and arrhythmias. Few reports exist describing arrhythmia induced by viper envenomation and to our knowledge none describe arrhythmia induced by Crotalinae envenomation. This report concerns the first known case of atrial fibrillation precipitated by rattlesnake bite. A 73-year-old Caucasian man with a past medical history of hypertension, hyperlipidemia, type 1 diabetes mellitus, and a baseline first-degree atrioventricular block presented to the emergency department following a rattlesnake bite to his left lower leg. He developed pain and swelling in his left leg two-hour post-envenomation and subsequently received four vials of Crotalidae polyvalent immune fab (ovine). At three-hour post-envenomation following transfer to the intensive care unit, an electrocardiogram revealed new-onset atrial fibrillation. An amiodarone drip was started and the patient successfully converted to normal sinus rhythm approximately six hours after he was found to be in atrial fibrillation. A transthoracic echocardiogram revealed mild concentric left ventricular hypertrophy and an ejection fraction of 72%. He was discharged the following day with no hematological abnormalities and a baseline first-degree atrioventricular block. This is the first documented case of reversible atrial fibrillation precipitated by Crotalinae envenomation. In patients with pertinent risk factors for developing atrial fibrillation, physicians should be aware of the potential for this arrhythmia. Direct toxic effects of venom or structural and electrophysiological cardiovascular abnormalities may predispose snakebite patients to arrhythmia, warranting extended and attentive cardiac monitoring.
Spontaneous conversion of atrial fibrillation caused by severe hyperkalemia: A case report.
Yan, Lihua; Jiang, Tingbo; Yang, Xiangjun; Xu, Mingzhu
2018-04-01
Hyperkalemia is a life-threatening electrolyte disturbance which could lead to arrhythmias and potentially death. An 82-year-old male patient who presented typical electrocardiographic indications of hyperkalemia, including the absence of P waves, prolongation of QRS complex, sinoventricular conduction, bradyarrhythmia and tall peaked T waves. He developed a rare self-defibrillation of atrial fibrillation to sinus rhythm due to hyperkalemia. Besides, he developed secondary thrombosis caused by abrupt termination of atrial fibrillation. This patient was diagnosed with hyperkalemia, hypertension, and AF. He was treated with an intravenous infusion of calcium gluconate, insulin and dextrose, an oral kayexalate, and emergency hemodialysis. The patient was managed effectively and discharged with stable status. Hyperkalemia could induce malignant arrhythmia with high mortality. Thus we suggested more attention be paid to monitoring electrolyte disorders and maintaining anticoagulation treatments to avoid thromboembolism.
Eisenberg, Nancy; Sulik, Michael J.; Spinrad, Tracy L.; Edwards, Alison; Eggum, Natalie D.; Liew, Jeffrey; Sallquist, Julie; Popp, Tierney K.; Smith, Cynthia L.; Hart, Daniel
2012-01-01
The purpose of the current study was to predict the development of aggressive behavior from young children’s respiratory sinus arrhythmia (RSA) and environmental quality. In a longitudinal sample of 213 children, baseline RSA, RSA suppression in response to a film of crying babies, and a composite measure of environmental quality (incorporating socioeconomic status and marital adjustment) were measured, and parent-reported aggression was assessed from 18 to 54 months of age. Predictions based on biological sensitivity-to-context/differential susceptibility and diathesis-stress models, as well as potential moderation by child sex, were examined. The interaction of baseline RSA with environmental quality predicted the development (slope) and 54-month intercept of mothers’ reports of aggression. For girls only, the interaction between baseline RSA and environmental quality predicted the 18-month intercept of fathers’ reports. In general, significant negative relations between RSA and aggression were found primarily at high levels of environmental quality. In addition, we found a significant Sex × RSA interaction predicting the slope and 54-month intercept of fathers’ reports of aggression, such that RSA was negatively related to aggression for boys but not for girls. Contrary to predictions, no significant main effects or interactions were found for RSA suppression. The results provide mixed but not full support for differential susceptibility theory and provide little support for the diathesis-stress model. PMID:22182294
El-Sheikh, Mona; Hinnant, J. Benjamin
2011-01-01
Allostatic load theory hypothesizes that stress and the body’s responses to stressors contribute to longer term physiological changes in multiple systems over time (allostasis), and that shifts in how these systems function have implications for adjustment and health. We investigated these hypotheses with longitudinal data from two independent samples (n = 413; 219 girls, 194 boys) with repeated measures at ages 8, 9, 10, and 11. Initial parental marital conflict and its change over time indexed children’s exposure to an important familial stressor, which was examined in interaction with children’s respiratory sinus arrhythmia (RSA) reactivity to laboratory tasks (stress response) to predict children’s basal levels of RSA over time. We also investigated children’s sex as an additional possible moderator. Our second research question focused on examining whether initial levels and changes in resting RSA over time predicted children’s externalizing behavior. Boys with a strong RSA suppression response to a frustrating laboratory task who experienced higher initial marital conflict or increasing marital conflict over time showed decreases in their resting RSA over time. In addition, boys’ initial resting RSA (but not changes in resting RSA over time) was negatively related to change over time in externalizing symptoms. Findings for girls were more mixed. Results are discussed in the context of developmental psychobiology, allostatic load, and implications for the development of psychopathology. PMID:21756434
Murdock, Kyle W; Fagundes, Christopher P
2017-04-01
Low childhood socioeconomic status (SES) is reliably associated with poor adult health. Social environments early in life and physiological stress responses are theorized to underlie this link; however, the role of attachment orientations is relatively unknown. In this study, we examined whether attachment orientations (i.e., attachment anxiety and attachment avoidance) and self-reported stress were mediators of the association between childhood SES and self-reported health in adulthood. Furthermore, we examined whether parasympathetic nervous system functioning was a moderator of associations between attachment orientations and self-reported stress. Participants (N = 213) provided self-reports of childhood SES, attachment orientations, general stress, and self-rated health. Respiratory sinus arrhythmia (RSA) was measured at rest, as well as during an acute social stressor. Low childhood SES was associated with poor self-reported health via the serial pathway from attachment anxiety to general stress. Moreover, attachment avoidance was associated with self-reported health via general stress, but only among those with high stress-induced RSA. Findings were independent of participant age, sex, race, body mass index, baseline RSA, and adult SES. Attachment theory is useful for understanding why those from low SES backgrounds are at greater risk of negative health outcomes in adulthood. Findings extend our knowledge of how interpersonal relationships in childhood can shape emotional and physical health outcomes in adulthood.
Murdock, Kyle W.; Fagundes, Christopher P.
2016-01-01
Background Low childhood SES is reliably associated with poor adult health. Social environments early in life and physiological stress responses are theorized to underlie this link; however, the role of attachment orientations is relatively unknown. Purpose In this study, we examined whether attachment orientations (i.e., attachment anxiety and attachment avoidance) and self-reported stress were mediators of the association between childhood SES and self-reported health in adulthood. Furthermore, we examined whether parasympathetic nervous system functioning was a moderator of associations between attachment orientations and self-reported stress. Methods Participants (N = 213) provided self-reports of childhood SES, attachment orientations, stress, and self-rated health. Respiratory sinus arrhythmia (RSA) was measured at rest, as well as during an acute social stressor. Results Low childhood SES was associated with poor self-reported health via the serial pathway from attachment anxiety to general stress. Moreover, attachment avoidance was associated with self-reported health via general stress, but only among those with high stress-induced RSA. Findings were independent of participant age, sex, race, body mass index, baseline RSA, and adult SES. Conclusions Attachment theory is useful for understanding why those from low SES backgrounds are at greater risk of negative health outcomes in adulthood. Findings extend our knowledge of how interpersonal relationships in childhood can shape emotional and physical health outcomes in adulthood. PMID:27679464
Patron, Elisabetta; Messerotti Benvenuti, Simone; Favretto, Giuseppe; Valfrè, Carlo; Bonfà, Carlotta; Gasparotto, Renata; Palomba, Daniela
2013-03-01
The current study investigated whether biofeedback training aimed at increasing respiratory sinus arrhythmia (RSA), a measure of cardiac vagal modulation, can reduce depressive symptoms in patients after cardiac surgery. This randomized controlled study enrolled 26 patients after first-time cardiac surgery. The patients were randomly assigned to an RSA-biofeedback group (N = 13) or to a treatment as usual group (N = 13). The biofeedback training consisted of five 45 min sessions designed to increase RSA. The outcome was assessed as changes in RSA and in the Centre for Epidemiologic Studies of Depression (CES-D) values from pre- to post-training. Both groups were comparable for demographic and biomedical characteristics. RSA increased significantly in patients who underwent RSA-biofeedback compared to controls. Moreover, the CES-D scores were reduced significantly from pre- to post-training in the RSA-biofeedback group compared to the controls. Changes in RSA were inversely related to changes in CES-D scores from pre- to post-training. These findings extend the effectiveness of RSA-biofeedback for increasing vagal modulation as well as for reducing depressive symptoms in post-surgical patients. Overall, the current study also suggests that this biobehavioral intervention may add to the efficacy of postoperative risk reduction programs and rehabilitation protocols in cardiac surgery patients.
Atypical patterns of respiratory sinus arrhythmia index an endophenotype for depression
Yaroslavsky, Ilya; Rottenberg, Jonathan; Kovacs, Maria
2015-01-01
Can atypical patterns of parasympathetic nervous system activity serve as endophenotypes for depression? Using respiratory sinus arrhythmia (RSA) as an index of parasympathetic nervous system function, we examined this question in two studies: one involving mothers with and without depression histories and their offspring (at high and low risk for depression, respectively), and a further study of adolescent sibling pairs concordant and discordant for major depression. In both studies, subjects were exposed to sad mood induction; subjects’ RSA was monitored during rest periods and in response to the mood induction. We used Gottesman and Gould’s (2003) criteria for an endophenotype and a priori defined “atypical” and “normative” RSA patterns (combinations of resting RSA and RSA reactivity). We found that atypical RSA patterns (a) predicted current depressive episodes and remission status among women with histories of juvenile onset depression and healthy controls, (b) predicted longitudinal trajectories of depressive symptoms among high- and low-risk young offspring, (c) were concordant across mothers and their juvenile offspring, (d) were more prevalent among never-depressed youth at high risk for depression than their low-risk peers, and (e) were more concordant across adolescent sibling pairs in which both versus only one had a history of major depression. Thus, the results support atypical RSA patterns as an endophenotype for depression. Possible mechanisms by which RSA patterns increase depression risk and their genetic contributors are discussed. PMID:25422965
NASA Technical Reports Server (NTRS)
Eckberg, Dwain L.
2003-01-01
Respiratory activity phasically alters membrane potentials of preganglionic vagal and sympathetic motoneurones and continuously modulates their responsiveness to stimulatory inputs. The most obvious manifestation of this 'respiratory gating' is respiratory sinus arrhythmia, the rhythmic fluctuations of electrocardiographic R-R intervals observed in healthy resting humans. Phasic autonomic motoneurone firing, reflecting the throughput of the system, depends importantly on the intensity of stimulatory inputs, such that when levels of stimulation are low (as with high arterial pressure and sympathetic activity, or low arterial pressure and vagal activity), respiratory fluctuations of sympathetic or vagal firing are also low. The respiratory gate has a finite capacity, and high levels of stimulation override the ability of respiration to gate autonomic responsiveness. Autonomic throughput also depends importantly on other factors, including especially, the frequency of breathing, the rate at which the gate opens and closes. Respiratory sinus arrhythmia is small at rapid, and large at slow breathing rates. The strong correlation between systolic pressure and R-R intervals at respiratory frequencies reflects the influence of respiration on these two measures, rather than arterial baroreflex physiology. A wide range of evidence suggests that respiratory activity gates the timing of autonomic motoneurone firing, but does not influence its tonic level. I propose that the most enduring significance of respiratory gating is its use as a precisely controlled experimental tool to tease out and better understand otherwise inaccessible human autonomic neurophysiological mechanisms.
Gouin, Jean-Philippe; Deschênes, Sonya S; Dugas, Michel J
2014-09-01
Respiratory sinus arrhythmia (RSA) has been conceptualized as an index of emotion regulation abilities. Although resting RSA has been associated with both concurrent and prospective affective responses to stress, the impact of RSA reactivity on emotional responses to stress is inconsistent across studies. The type of emotional stimuli used to elicit these phasic RSA responses may influence the adaptive value of RSA reactivity. We propose that RSA reactivity to a personally relevant worry-based stressor might forecast future affective responses to stress. To evaluate whether resting RSA and RSA reactivity to worry inductions predict stress-related increases in psychological distress, an academic stress model was used to prospectively examine changes in psychological distress from the well-defined low- and high-stress periods. During the low-stress period, 76 participants completed self-report mood measures and had their RSA assessed during a resting baseline, free worry period and worry catastrophizing interview. Participants completed another mood assessment during the high-stress period. Results indicated that baseline psychological distress predicted larger decreases in RSA during the worry inductions. Lower resting RSA and greater RSA suppression to the worry inductions at baseline prospectively predicted larger increases in psychological distress from the low- to high-stress period, even after accounting for the impact of baseline distress on RSA. These results provide further evidence that RSA may represent a unique index of emotion regulation abilities in times of stress.
El-Sheikh, Mona; Hinnant, J Benjamin
2011-08-01
Allostatic load theory hypothesizes that stress and the body's responses to stressors contribute to longer term physiological changes in multiple systems over time (allostasis), and that shifts in how these systems function have implications for adjustment and health. We investigated these hypotheses with longitudinal data from two independent samples (n = 413; 219 girls, 194 boys) with repeated measures at ages 8, 9, 10, and 11. Initial parental marital conflict and its change over time indexed children's exposure to an important familial stressor, which was examined in interaction with children's respiratory sinus arrhythmia (RSA) reactivity to laboratory tasks (stress response) to predict children's basal levels of RSA over time. We also investigated children's sex as an additional possible moderator. Our second research question focused on examining whether initial levels and changes in resting RSA over time predicted children's externalizing behavior. Boys with a strong RSA suppression response to a frustrating laboratory task who experienced higher initial marital conflict or increasing marital conflict over time showed decreases in their resting RSA over time. In addition, boys' initial resting RSA (but not changes in resting RSA over time) was negatively related to change over time in externalizing symptoms. Findings for girls were more mixed. Results are discussed in the context of developmental psychobiology, allostatic load, and implications for the development of psychopathology.
Supraventricular tachycardia after fenoterol inhalation: report of two cases.
Hung, Yu-Fa; Yang, Winnie; Chang, Mei-Ling
2003-01-01
Supraventricular tachycardia (SVT) following fenoterol inhalation in metered-dose inhaler (MDI) has never been reported. We report two cases of SVT after fenoterol inhalation in MDI. Case one was a 4-year-old boy who had asthma since early childhood. Paroxysmal supraventricular tachycardia (PSVT) was found after fenoterol inhalation (MDI), which returned to normal sinus rhythm following adenosine injection. The other one was a 9-year-old male who also had asthma since early childhood. He suffered from attacks of PSVT four times after fenoterol inhalation within one year. After verapamil injection and vagal maneuvers, PSVT was converted to normal sinus rhythm. There were no other episodes of SVT after discontinuing usage of fenoterol inhalation for 2 years in the follow-up. We report these two cases to remind pediatricians that cardiac arrhythmias should be evaluated following fenoterol inhalation (MDI).
Diameters of the cavo-sinus-tricuspid area in relation to type I atrial flutter.
Kozłowski, Dariusz; Hreczecha, Jolanta; Skwarek, Magdalena; Piwko, Grzegorz; Kosiński, Adam; Gawrysiak, Marcin; Grzybiak, Marek
2003-05-01
Cardiac arrhythmias have troubled patients and fascinated physicians for centuries. The twentieth century was an era of progress, when the mechanism of cardiac disorders became more commonly recognised. Arrhythmias may be due to abnormalities of automaticity, to abnormalities of conduction, or to a combination of both. In order for re-entry to occur, an area of slowing conduction combined with unidirectional block must be present. Much investigation has centred on the underlying re-entry mechanisms of atrial flutter. In the light of these facts, it would seem that a close acquaintance with the detailed topography of the vena cava orifice (cavo), coronary sinus orifice (sinus) and the attachment of the septal leaflet of the tricuspid valve (tricupid) area could be of great interest, especially for invasive cardiologists. The research was conducted carried out on material consisting of 41 hearts of humans of both sexes from the age of 12 to 80 (6 female, 35 male). Classical macroscopic methods of anatomical evaluation were used. The following measurements were made: the shortest distance between the Eustachian valve and the attachment of the tricuspid valve on the left margin of the coronary sinus orifice (diameter 1), the distance between the attachment of the tricuspid valve and the inferior margin of the sinus orifice (diameter 2), the distance between the Eustachian valve and the attachment of the tricuspid valve on the right margin of the coronary sinus orifice (diameter 3), the distance between the inferior margin of the vena cava inferior and the attachment of the tricuspid valve (diameter 4) and, finally, the diameter between the attachment of the septal cusp of the tricuspid valve and the extemal border of the vena cava inferior (diameter 5). No correlation was found between the age and sex of the three groups of the material. The dimensions of the structure examined were similar in the three groups of hearts. In young adult hearts all the diameters measured ranged from 4 to 47 mm. The average diameters were, respectively: 15.02 mm (diameter 1), 8.97 mm (diameter 2), 17.27 mm (diameter 3), 26.87 mm (diameter 4), 36.42 mm (diameter 5). In the mature adult hearts all the diameters measured ranged from 8 to 45 mm; 18.19 mm (diameter 1), 10.54 mm (diameter 2), 19.95 mm (diameter 3), 28.90 mm (diameter 4), 39.63 mm (diameter 5). In the older adults hearts all the diameters measured ranged from 4 to 47 mm. The average diameters were, respectively: 15.65 mm (diameter 1), 8.70 mm (diameter 2), 7.25 mm (diameter 3), 26.80 mm (diameter 4), 35.85 mm (diameter 5). On the basis of our study we were able to conclude that the diameters of the cavo-sinus-tricuspid area were constant and did not differ significantly within the three (young, mature, old) adult groups examined.
Chen, Jan-Yow; Liu, Jiung-Hsiun; Wu, Hong-Dar Isaac; Lin, Kuo-Hung; Chang, Kuan-Cheng; Liou, Ying-Ming
2016-01-01
Background Familial sick sinus syndrome is associated with gene mutations and dysfunction of ion channels. In contrast, degenerative fibrosis of the sinus node tissue plays an important role in the pathogenesis of acquired sick sinus syndrome. There is a close relationship between transforming growth factor-β1 mediated cardiac fibrosis and acquired arrhythmia. It is of interest to examine whether transforming growth factor-β1 is involved in the pathogenesis of acquired sick sinus syndrome. Methods Overall, 110 patients with acquired SSS and 137 age/gender-matched controls were screened for transforming growth factor-β1 and cardiac sodium channel gene polymorphisms using gene sequencing or restriction fragment length polymorphism methods. An enzyme-linked immunosorbent assay was used to determine the serum level of transforming growth factor-β1. Results Two transforming growth factor-β1 gene polymorphisms (C-509T and T+869C) and one cardiac sodium channel gene polymorphism (H588R) have been identified. The C-dominant CC/CT genotype frequency of T869C was significantly higher in acquired sick sinus syndrome patients than in controls (OR 2.09, 95% CI 1.16–3.75, P = 0.01). Consistently, the level of serum transforming growth factor-β1 was also significantly greater in acquired sick sinus syndrome group than in controls (5.3±3.4 ng/ml vs. 3.7±2.4 ng/ml, P = 0.01). In addition, the CC/CT genotypes showed a higher transforming growth factor-β1 serum level than the TT genotype (4.25 ± 2.50 ng/ml vs. 2.71± 1.76 ng/ml, P = 0.028) in controls. Conclusion Transforming growth factor-β1 T869C polymorphism, correlated with high serum transforming growth factor-β1 levels, is associated with susceptibility to acquired sick sinus syndrome. PMID:27380173
Tricyclic antidepressant overdose: emergency department findings as predictors of clinical course.
Foulke, G E; Albertson, T E; Walby, W F
1986-11-01
There is controversy regarding the appropriate utilization of health care resources in the management of tricyclic antidepressant overdosage. Antidepressant overdose patients presenting to the emergency department (ED) are routinely admitted to intensive care units, but only a small proportion develop cardiac arrhythmias or other complications requiring such an environment. The authors reviewed the findings in 165 patients presenting to an ED with antidepressant overdose. They found that major manifestations of toxicity on ED evaluation (altered mental status, seizures, arrhythmias, and conduction defects) were commonly associated with a complicated hospital course. Patients with the isolated findings of sinus tachycardia or QTc prolongation had no complications. No patient experienced a serious toxic event without major evidence of toxicity on ED evaluation and continued evidence of toxicity during the hospital course. These data support the concept that proper ED evaluation can identify a large body of patients with trivial ingestions who may not require hospital observation.
How revealing are insertable loop recorders in pediatrics?
Frangini, Patricia A; Cecchin, Frank; Jordao, Ligia; Martuscello, Maria; Alexander, Mark E; Triedman, John K; Walsh, Edward P; Berul, Charles I
2008-03-01
An insertable loop recorder (ILR) in patients with infrequent syncope or palpitations may be useful to decide management strategies, including clinical observation, medical therapy, pacemaker, or implantable cardioverter defibrillator (ICD). We sought to determine the diagnostic utility of the Reveal ILR (Medtronic, Inc., Minneapolis, MN, USA) in pediatric patients. Retrospective review of clinical data, indications, findings, and therapeutic decision in 27 consecutive patients who underwent ILR implantation from 1998-2007. The median age was 14.8 years (2-25 years). Indications were syncope in 24 patients and recurrent palpitations in three. Overall, eight patients had structural heart disease (six congenital heart disease, one hypertrophic cardiomyopathy, one Kawasaki), five had previous documented ventricular arrhythmias with negative evaluation including electrophysiology study, and three patients had QT prolongation. Tilt testing was performed in 10 patients, of which five had neurocardiogenic syncope but recurrent episodes despite medical therapy. After median three months (1-20 months), 17 patients presented with symptoms and the ILR memory was analyzed in 16 (no episode stored in one due to full device memory), showing asystole or transient atrioventricular (AV) block (2), sinus bradycardia (6), or normal sinus rhythm (8). Among asymptomatic patients, 3/10 had intermittent AV block or long pauses, automatically detected and stored by the ILR. In 19 of 20 patients, ILR was diagnostic (95%) and five subsequently underwent pacemaker implantation, while seven patients remained asymptomatic without ILR events. Notably, no life-threatening events were detected. The ILR was explanted in 22 patients after a median of 22 months, two due to pocket infection, 12 for battery depletion and eight after clear documentation of nonmalignant arrhythmia. The ILR in pediatrics is a useful adjunct to other diagnostic studies. Patient selection is critical as the ILR should not be utilized for malignant arrhythmias. A diagnosis is attained in the majority of symptomatic patients, predominantly bradyarrhythmias including pauses and intermittent AV block.
Ambler, Jonathan J S; Deakin, Charles D
2006-11-01
Biphasic waveforms have similar or greater efficacy at cardioverting atrial and ventricular arrhythmias at lower energy levels than monophasic waveforms, and cause less ST depression following defibrillation of ventricular fibrillation. No studies have investigated this effect on ST change with atrial arrhythmias. We studied the efficacy of the Welch Allyn-MRL PIC biphasic defibrillator. One hundred and thirty-nine patients undergoing elective DC cardioversion for atrial arrhythmias were randomised to cardioversion by monophasic (Hewlett Packard Codemaster XL; 100, 200, 300, 360 and 360J) or biphasic (Welch Allyn-MRL PIC; 70, 100, 150, 200 and 300J) defibrillator. We analysed success of cardioversion after 0 and 30min, cumulative energy, number of shocks and energy at successful cardioversion. The ST change in the recorded electrocardiogram was measured at 15s after all shocks using electronic callipers. Immediately after cardioversion 59/68 (86.8%) of the monophasic group versus 56/60 (93.3%) of the biphasic group were in sinus rhythm. Of the monophasic group, 55/67 (82.1%) remained in sinus rhythm at 30min versus 53/58 (91.4%) of the biphasic group. These differences were not significant at 0min (P=0.35) or 30min (P=0.21). The biphasic group required significantly fewer shocks (P=0.006), less cumulative energy (P<0.0001) and required lower total energy for successful cardioversion (P<0.0001). Of the 102 patients with electrocardiogram recordings suitable for analysis, ST segment change was greater in the monophasic group (P=0.037). The Welch Allyn-MRL biphasic waveform for DC cardioversion results in fewer shocks, with less cumulative energy delivered and less post shock ST change than with a Hewlett Packard Codemaster XL damped sine wave monophasic waveform.
The management of ventricular dysrhythmia in aconite poisoning.
Coulson, James M; Caparrotta, Thomas M; Thompson, John P
2017-06-01
Aconite poisoning is relatively rare but is frequently complicated by ventricular dysrhythmias, which may be fatal. Molecular basis of aconite alkaloid ventricular arrhythmogenicity: Aconite exerts its toxic effects due to the presence of an admixture of alkaloids present in all parts of the plant. The major target of these aconite alkaloids is the fast voltage-gates sodium channel, where they cause persistent activation. This blockade of the channel in the activated state promotes automaticity within the ventricular myocardium and the generation of ventricular arrhythmias. Aconitine-induced arrhythmias: Aconite alkaloids are known to cause many different types of disturbance of heart rhythm. However, this focused review specifically looks at ventricular rhythm disturbances, namely ventricular ectopy, ventricular tachycardia, torsades des pointes and ventricular fibrillation. The objective of this review was to identify the outcome of anti-dysrhythmic strategies from animal studies and case reports in humans in order to guide the management of ventricular dysrhythmias in aconite poisoning in humans. A review of the literature in English was conducted in PubMed and Google Scholar from 1966 to July 2016 using the search terms "aconite/aconitine"; "aconite/aconitine + poisoning" and "aconite/aconitine + dysrhythmia". 168 human case-reports and case-series were identified by these searches, of which 103 were rejected if exposure to aconite did not result in ventricular dysrhythmias, if it was uncertain as to whether aconite had been ingested, if other agents were co-ingested, if there was insufficient information to determine the type of treatments administered or if there was insufficient information to determine outcome. Thus, 65 case reports of probable aconite poisoning that resulted in ventricular dysrhythmias were identified. Toxicokinetic data in aconite poisoning: Data were only available in three papers; the presence of ventricular rhythm disturbances directly correlated with the concentration of aconite alkaloids in the plasma. 54 of 65 cases developed ventricular tachycardia, six developed torsades des pointes, 15 patients developed ventricular fibrillation, 10 developed ventricular ectopics and one developed a broad complex tachycardia not otherwise specified; each dysrhythmia was regarded as separate and patients may have had more than one dysrhythmia. 10 patients died, giving a mortality of 15%. In total, 147 treatments were administered to 65 patients. 46 of the interventions were assessed by the authors as having been associated with successful restoration of sinus rhythm. Flecainide administration was accompanied by dysrhythmia termination in six of seven cases. Mexiletine was connected with correcting dysrhythmias in 3 of 3 cases. Procainamide administration was associated with return to sinus rhythm in 2 of 2 cases. Prolonged cardio-pulmonary resuscitation was administered to 15 patients where it was associated with a return to sinus rhythm in nine of these. Amiodarone was linked to success in correcting dysrhythmias in 11 of 20 cases. Cardiopulmonary bypass use was associated with a return to sinus rhythm in four out of six cases. Epinephrine was documented as being employed on four occasions, and was associated with a restoration of sinus rhythm on two of these. Magnesium sulphate administration was accompanied by dysrhythmia termination in two of nine cases. Direct cardioversion was associated with a return of sinus rhythm in 5 of 30 cases. However, it is not certain whether the drug treatment influenced the course of the dysrhythmia. Based on the evidence available from human case reports, flecainaide or amiodarone appear to be more associated with a return to sinus rhythm than lidocaine and/or cardioversion, although it is not established whether the administration of treatment caused reversion to normal sinus rhythm. The potential beneficial effects of amiodarone were not observed in animal studies. This may be due to intra-species differences between ion channels or relate to the wider cardiovascular toxicity of aconite that extends beyond arrhythmias. Prolonged cardiopulmonary resuscitation and cardiopulmonary bypass should be considered as an integral part of good clinical care as "time-buying" strategies to allow the body to excrete the toxic alkaloids. There may also be a role for mexiletine, procainamide and magnesium sulphate.
Investigation of mechanisms and non-pharmacological therapy of cardiac arrhythmias
NASA Astrophysics Data System (ADS)
Vago, Hajnalka
Learning of mechanisms of arrhythmias may contribute substantially to the development of effective pharmacological and non-pharmacological therapeutic methods. Clinical relevance of endothelin-1 (ET-1), a strong vasoconstrictor and arrhythmogenic endogenous substrate, is not clarified yet. In our experimental studies, performed in the in situ canine heart, electrophysiological effects and the role in the pathomechanism of malignant ventricular tachyarrhythmias of endogenous and exogenous ET-1 was investigated. It has been proven in the in vivo ischaemia-reperfusion canine heart model, that during reperfusion ET-1 and big-ET levels increase in the coronary sinus, however there was no correlation between endothelin levels and electrophysiological changes. ET A-receptor antagonist darusentan does not prevent electrophysiological changes and development of ventricular tachyarrhythmias during ischaemia and reperfusion. On the contrary, during ischaemia endogenous ET-1 tends to show balancing effect. It has been proven that administration of high dose intracoronary ET-1 bolus has dual, ischaemic and direct, electrophysiological effect. It has been shown for the first time, that ET-1 causes monophasic action potential (MAP) and T-wave alternant. Our clinical study leads to the conclusion that previous atrial fibrillation, absence of preoperative beta-blocker treatment and combined heart surgery are strong predictors of atrial fibrillation following open heart surgery. The basis of new nonpharmacological therapies is the learning of pathomechanisms of arrhythmias and in some cases heart failure, which is an arrhythmogenic substrate. In our experimental study reliable MAP measurements, suitable for investigation of arrhythmogenesis, were performed for the first time using fractally coated ablation catheters during spontaneous rate and during stimulations. It has been proven that radiofrequency ablation affects significantly MAP parameters. In Hungary, we were the first to apply effectively biatrial pacemaker and biatrial cardioverter defibrillator for the prevention of paroxysmal atrial fibrillation. In the majority of patients frequency of paroxysmal atrial fibrillation decreased significantly due to biatrial stimulation or combined pharmacological and resynchronisation therapy. Parasymphathetic cardiac neurostimulation is a promising new non-pharmacological treatment option in certain types of arrhythmias. In our clinical study we were able to stimulate cardiac parasympathetic nerves innervating atrioventricular node achieving ventricular rate control during atrial tachyarrhythmias with chronically implanted coronary sinus lead. In our study biventricular pacemakers and cardioverter defibrillators were applied successfully in the treatment of drug refractory congestive heart failure combined with inter- and/or intraventricular conduction disturbances. AV sequential left sided chronic pacing using a single lead located in the coronary sinus has not been previously reported. Left sided DDD pacing was effective chronically in the improvement of the functional stage of patient suffering from congestive heart disease combined with left bundle branch block and binodal disease. Parallel with the investigation of pathomechanism of life-threatening ventricular tachyarrhythmias and the most common, clinically relevant atrial fibrillation due to recent technical development, we were able to support nonpharmacological therapeutic modalities, gaining popularity in clinical management, with novel observations.
Tsiflikas, Ilias; Drosch, Tanja; Brodoefel, Harald; Thomas, Christoph; Reimann, Anja; Till, Alexander; Nittka, Daniel; Kopp, Andreas F; Schroeder, Stephen; Heuschmid, Martin; Burgstahler, Christof
2010-08-06
Cardiac multi-detector computed tomography (MDCT) permits accurate visualization of high-grade coronary artery stenosis. However, in patients with heart rate irregularities, MDCT was found to have limitations. Thus, the aim of the present study was to evaluate the diagnostic accuracy of a new dual-source computed tomography (DSCT) scanner generation with 83 ms temporal resolution in patients without stable sinus rhythm. 44 patients (31 men, mean age 67.5+/-9.2 years) without stable sinus rhythm and scheduled for invasive coronary angiography (ICA) because of suspected (n=17) or known coronary artery disease (CAD, n=27) were included in this study. All patients were examined with DSCT (Somatom Definition, Siemens). Besides assessment of total calcium score, all coronary segments were analyzed with regard to the presence of significant coronary artery lesions (>50%). The findings were compared to ICA in a blinded fashion. During CT examination, heart rhythm was as follows: 25 patients (57%) atrial fibrillation, 7 patients (16%) ventricular extrasystoles (two of them with atrial fibrillation), 4 patients (9%) supraventricular extrasystoles, 10 patients (23%) sinus arrhythmia (heart rate variability>10 bpm). Mean heart rate was 69+/-14 bpm, median 65 bpm. Mean Agatston score equivalent (ASE) was 762, ranging from 0 to 4949.7 ASE. Prevalence of CAD was 68% (30/44). 155 segments (27%) showed "step-ladder" artifacts and 28 segments (5%) could not be visualized by DSCT. Only 70 segments (12%) were completely imaged without any artifacts. Based on a coronary segment model, sensitivity was 73%, specificity 91%, positive predictive value 63%, and negative predictive value 94% for the detection of significant lesions (>or=50% diameter stenosis). Overall accuracy was 88%. In patients with heart rate irregularities, including patients with atrial fibrillation and a high prevalence of coronary artery disease, the diagnostic yield of dual-source computed tomography is still hampered due to a high number of segments with "step-ladder" artifacts. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.
[The use of auto mode switching in patients with sick sinus syndrome].
Vlasínová, J
2005-01-01
At present the dual chamber pacing, originally developed for patients with AV blockades, is widely used also for patients with Sick sinus syndrome (tachycardic-bradycardic type). But these patients often cause therapeutical problems to their physicians. In these cases either antiarrhythmic therapy is necessary to prevent recurrent supraventricular tachycardias (which are cause of rapid ventricular pacing) or in the case of failure of AA therapy the pacing mode has to be changed to DDI/R, which excludes physiological VAT pacing. The Auto Mode Switching (AMS) function ensures adequate ventricular pacing rate in the time of SV arrhythmias. Effects of dual chamber pacemakers equipped with AMS were studied in a group of patients with paroxysmal atrial fibrilation and/or atrial flutter. Therapy brings effects in lower of expenses due to less frequent visits at the physician, lower rate of rehospitalizations and lower need for powerful AA therapy.
[The risk of direct current countershock].
Gajek, J; Zyśko, D
2001-07-01
Direct current cardioversion (DCC) is a procedure commonly used to restore the sinus rhythm in patients with supraventricular and ventricular arrhythmias. Its safety, regarding the use of electric current, is still a matter of controversy and debate. The patients with atrial fibrillation/flutter, supraventricular or ventricular tachycardia represent a broad spectrum of clinical conditions and it is difficult to draw the conclusions. The high success rate of DCC in restoring the sinus rhythm, may be partly responsible for enhancing and revealing proarrhythmic properties of antiarrhythmic drugs. The deaths described as a complications of DCC were mainly due to the proarrhythmia and less common to the progression of the pathologic process. The embolic, arrhythmic and anesthetic complications of DCC can be prevented if the known recommendations of performing the DCC are followed. The authors review critically the literature data about the complications of the procedure and come to the conclusion of safety of DCC.
Autonomic Cardiovascular Control and Executive Function in Chronic Hypotension.
Duschek, Stefan; Hoffmann, Alexandra; Reyes Del Paso, Gustavo A; Ettinger, Ulrich
2017-06-01
Chronic low blood pressure (hypotension) is characterized by complaints such as fatigue, reduced drive, dizziness, and cold limbs. Additionally, deficits in attention and memory have been observed. Autonomic dysregulation is considered to be involved in the origin of this condition. The study explored autonomic cardiovascular control in the context of higher cognitive processing (executive function) in hypotension. Hemodynamic recordings were performed in 40 hypotensive and 40 normotensive participants during execution of four classical executive function tasks (number-letter task, n-back task, continuous performance test, and flanker task). Parameters of cardiac sympathetic control, i.e., stroke volume, cardiac output, pre-ejection period, total peripheral resistance, and parasympathetic control, i.e., respiratory sinus arrhythmia and baroreflex sensitivity, were obtained. The hypotensive group exhibited lower stroke volume and cardiac output, as well as higher pre-ejection period and baroreflex sensitivity during task execution. Increased error rates in hypotensive individuals were observed in the n-back and flanker tasks. In the total sample, there were positive correlations of error rates with pre-ejection period, baroreflex sensitivity and respiratory sinus arrhythmia, and negative correlations with cardiac output. Group differences in stroke volume, cardiac output, and pre-ejection period suggest diminished beta-adrenergic myocardial drive during executive function processing in hypotension, in addition to increased baroreflex function. Although further research is warranted to quantify the extent of executive function impairment in hypotension, the results from correlation analysis add evidence to the notion that higher sympathetic inotropic influences and reduced parasympathetic cardiac influences are accompanied by better cognitive performance.
Abaied, Jamie L; Wagner, Caitlin; Breslend, Nicole Lafko; Flynn, Megan
2016-04-01
This longitudinal study examined the prospective contribution of respiratory sinus arrhythmia (RSA), a key physiological indicator of self-regulation, to eating disorder symptoms in college students, and whether this link was moderated by maladaptive responses to stress and parent psychological control. At Wave 1, college students' RSA was measured at rest. At Waves 1 and 2 (six-month follow-up), students reported on their eating disorder symptoms, coping and involuntary responses to stress, and perceptions of their parents' use of psychological control. Significant three-way interactions indicated that the link between RSA and subsequent eating disorder symptoms was contingent on responses to stress and parent psychological control. In the context of maladaptive responses to stress and high psychological control, RSA predicted increased eating disorder symptoms over time. In the absence of parent psychological control, high RSA was beneficial in most cases, even when individuals reported maladaptive responses to stress. This study presents novel evidence that high RSA contributes to risk for or resilience to eating disorder symptoms over time. RSA can be protective against eating disorder symptoms, but in some contexts, the self-regulation resources that high RSA provides may be inappropriately applied to eating cognitions and behaviors. This research highlights the importance of examining physiological functioning conjointly with other risk factors as precursors to eating disorder symptoms over time. Copyright © 2016. Published by Elsevier Ltd.
Porges, Stephen W; Macellaio, Matthew; Stanfill, Shannon D; McCue, Kimberly; Lewis, Gregory F; Harden, Emily R; Handelman, Mika; Denver, John; Bazhenova, Olga V; Heilman, Keri J
2013-06-01
The current study evaluated processes underlying two common symptoms (i.e., state regulation problems and deficits in auditory processing) associated with a diagnosis of autism spectrum disorders. Although these symptoms have been treated in the literature as unrelated, when informed by the Polyvagal Theory, these symptoms may be viewed as the predictable consequences of depressed neural regulation of an integrated social engagement system, in which there is down regulation of neural influences to the heart (i.e., via the vagus) and to the middle ear muscles (i.e., via the facial and trigeminal cranial nerves). Respiratory sinus arrhythmia (RSA) and heart period were monitored to evaluate state regulation during a baseline and two auditory processing tasks (i.e., the SCAN tests for Filtered Words and Competing Words), which were used to evaluate auditory processing performance. Children with a diagnosis of autism spectrum disorders (ASD) were contrasted with aged matched typically developing children. The current study identified three features that distinguished the ASD group from a group of typically developing children: 1) baseline RSA, 2) direction of RSA reactivity, and 3) auditory processing performance. In the ASD group, the pattern of change in RSA during the attention demanding SCAN tests moderated the relation between performance on the Competing Words test and IQ. In addition, in a subset of ASD participants, auditory processing performance improved and RSA increased following an intervention designed to improve auditory processing. Copyright © 2012 Elsevier B.V. All rights reserved.
Fortunato, Christine K.; Gatzke-Kopp, Lisa M.; Ram, Nilam
2015-01-01
Internalizing and externalizing disorders are often, though inconsistently in studies of young children, associated with low baseline levels of respiratory sinus arrhythmia (RSA). RSA is thus considered to reflect the capacity for flexible and regulated affective reactivity and a general propensity for psychopathology. However, studies assessing RSA reactivity to emotional challenges tend to report more consistent associations with internalizing than with externalizing disorders, although it is unclear whether this is a function of the type of emotion challenges used. In the present study, we examined whether baseline RSA was associated with internalizing and/or externalizing severity in a sample of 273 young children (ages 5–6) with elevated symptoms of psychopathology. Following motivation-based models of emotion, we also tested whether RSA reactivity during withdrawal-based (fear, sadness) and approach-based (happiness, anger) emotion inductions was differentially associated with internalizing and externalizing symptoms, respectively. Baseline RSA was not associated with externalizing or internalizing symptom severity. However, RSA reactivity to specific emotional challenges was associated differentially with each symptom domain. As expected, internalizing symptom severity was associated with greater RSA withdrawal (increased arousal) during fearful and sad film segments. Conversely, externalizing symptom severity was related to blunted RSA withdrawal during a happy film segment. The use of theoretically derived stimuli may be important in characterizing the nature of the deficits in emotion processing that differentiate the internalizing and externalizing domains of psychopathology. PMID:23233122
Viana, Andres G; Palmer, Cara A; Zvolensky, Michael J; Alfano, Candice A; Dixon, Laura J; Raines, Elizabeth M
2017-06-01
Although behavioral inhibition (BI) is clearly identified as a temperamental risk factor for childhood anxiety psychopathology, much less is known about whether the strength of this association may vary as a function of parasympathetic nervous system regulation in children with anxiety disorders. To build upon extant research in this area, the present study examined whether respiratory sinus arrhythmia (RSA) can explicate the conditions in which BI is linked to increased symptom severity among anxiety-disordered children (N = 44; M = 9.61 years, SD = 1.63; 52% female and African American, respectively). We examined RSA responding both during a basal period and during a stressor ("challenge" RSA): interacting with a "mystery guest" who was wearing a mask. As hypothesized, the interaction between BI and both basal and challenge RSA was significantly related to anxiety disorder symptom severity, even after controlling for depressive symptoms. The form of the interaction indicated that highest levels of anxiety disorder symptoms were found among children with high levels of BI and low basal and challenge RSA, respectively. These data provide novel empirical evidence of a clinically-relevant interplay between RSA and BI in relation to anxiety disorder symptom severity among clinical youth. Future work is needed to expand on the specific mechanisms that may be responsible e for the interplay between temperamental and psychobiological risks for childhood anxiety. Copyright © 2017 Elsevier Ltd. All rights reserved.
Diagnostic Role of ECG Recording Simultaneously With EEG Testing.
Kendirli, Mustafa Tansel; Aparci, Mustafa; Kendirli, Nurten; Tekeli, Hakan; Karaoglan, Mustafa; Senol, Mehmet Guney; Togrol, Erdem
2015-07-01
Arrhythmia is not uncommon in the etiology of syncope which mimics epilepsy. Data about the epilepsy induced vagal tonus abnormalities have being increasingly reported. So we aimed to evaluate what a neurologist may gain by a simultaneous electrocardiogram (ECG) and electroencephalogram (EEG) recording in the patients who underwent EEG testing due to prediagnosis of epilepsy. We retrospectively evaluated and detected ECG abnormalities in 68 (18%) of 376 patients who underwent EEG testing. A minimum of 20 of minutes artifact-free recording were required for each patient. Standard 1-channel ECG was simultaneously recorded in conjunction with the EEG. In all, 28% of females and 14% of males had ECG abnormalities. Females (mean age 49 years, range 18-88 years) were older compared with the male group (mean age 28 years, range 16-83 years). Atrial fibrillation was more frequent in female group whereas bradycardia and respiratory sinus arrhythmia was higher in male group. One case had been detected a critical asystole indicating sick sinus syndrome in the female group and treated with a pacemaker implantation in the following period. Simultaneous ECG recording in conjunction with EEG testing is a clinical prerequisite to detect and to clarify the coexisting ECG and EEG abnormalities and their clinical relevance. Potentially rare lethal causes of syncope that mimic seizure or those that could cause resistance to antiepileptic therapy could effectively be distinguished by detecting ECG abnormalities coinciding with the signs and abnormalities during EEG recording. © EEG and Clinical Neuroscience Society (ECNS) 2014.
Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation.
Lafuente-Lafuente, Carmelo; Valembois, Lucie; Bergmann, Jean-François; Belmin, Joël
2015-03-28
Atrial fibrillation is the most frequent sustained arrhythmia. Atrial fibrillation frequently recurs after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence, but the effect of these drugs on mortality and other clinical outcomes is unclear. This is an update of a review previously published in 2008 and 2012. To determine in patients who have recovered sinus rhythm after having atrial fibrillation, the effects of long-term treatment with antiarrhythmic drugs on death, stroke, embolism, drug adverse effects and recurrence of atrial fibrillation. We updated the searches of CENTRAL in The Cochrane Library (2013, Issue 12 of 12), MEDLINE (to January 2014) and EMBASE (to January 2014). The reference lists of retrieved articles, recent reviews and meta-analyses were checked. Two independent authors selected randomised controlled trials comparing any antiarrhythmic drug with a control (no treatment, placebo, drugs for rate control) or with another antiarrhythmic drug in adults who had atrial fibrillation and in whom sinus rhythm was restored. Post-operative atrial fibrillation was excluded. Two authors independently assessed quality and extracted data. Studies were pooled, if appropriate, using Peto odds ratio (OR). All results were calculated at one year of follow-up. In this update three new studies, with 534 patients, were included making a total of 59 included studies comprising 21,305 patients. All included studies were randomised controlled trials. Allocation concealment was adequate in 17 trials, it was unclear in the remaining 42 trials. Risk of bias was assessed in all domains only in the trials included in this update.Compared with controls, class IA drugs quinidine and disopyramide (OR 2.39, 95% confidence interval (95% CI) 1.03 to 5.59, number needed to treat to harm (NNTH) 109, 95% CI 34 to 4985) and sotalol (OR 2.23, 95% CI 1.1 to 4.50, NNTH 169, 95% CI 60 to 2068) were associated with increased all-cause mortality. Other antiarrhythmics did not seem to modify mortality, but our data could be underpowered to detect mild increases in mortality for several of the drugs studied.Several class IA (disopyramide, quinidine), IC (flecainide, propafenone) and III (amiodarone, dofetilide, dronedarone, sotalol) drugs significantly reduced recurrence of atrial fibrillation (OR 0.19 to 0.70, number needed to treat to beneft (NNTB) 3 to 16). Beta-blockers (metoprolol) also significantly reduced atrial fibrillation recurrences (OR 0.62, 95% CI 0.44 to 0.88, NNTB 9).All analysed drugs increased withdrawals due to adverse affects and all but amiodarone, dronedarone and propafenone increased pro-arrhythmia. Only 11 trials reported data on stroke. None of them found any significant difference with the exception of a single trial than found less strokes in the group treated with dronedarone compared to placebo. This finding was not confirmed in others studies on dronedarone.We could not analyse heart failure and use of anticoagulation because few original studies reported on these measures. Several class IA, IC and III drugs, as well as class II drugs (beta-blockers), are moderately effective in maintaining sinus rhythm after conversion of atrial fibrillation. However, they increase adverse events, including pro-arrhythmia, and some of them (disopyramide, quinidine and sotalol) may increase mortality. Possible benefits on clinically relevant outcomes (stroke, embolism, heart failure) remain to be established.
Hoffmayer, Kurt S; Bhave, Prashant D; Marcus, Gregory M; James, Cynthia A; Tichnell, Crystal; Chopra, Nagesh; Moxey, Laura; Krahn, Andrew D; Dixit, Sanjay; Stevenson, William; Calkins, Hugh; Badhwar, Nitish; Gerstenfeld, Edward P; Scheinman, Melvin M
2013-04-01
Ventricular arrhythmias in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and idiopathic ventricular tachycardia (VT) can share a left bundle branch block/inferior axis morphology. We previously reported electrocardiogram characteristics during outflow tract ventricular arrhythmias that helped distinguish VT related to ARVD/C from idiopathic VT. To prospectively validate these criteria. We created a risk score by using a derivation cohort. Two experienced electrophysiologists blinded to the diagnosis prospectively scored patients with VT/premature ventricular contractions (PVCs) with left bundle branch block/inferior axis pattern in a validation cohort of 37 ARVD/C tracings and 49 idiopathic VT tracings. All patients with ARVD/C had their diagnosis confirmed based on the revised task force criteria. Patients with idiopathic VT were selected based on structurally normal hearts with documented right ventricular outflow tract VT successfully treated with ablation. The scoring system provides 3 points for sinus rhythm anterior T-wave inversions in leads V1-V3 and during ventricular arrhythmia: 2 points for QRS duration in lead I≥120 ms, 2 points for QRS notching, and 1 point for precordial transition at lead V5 or later. A score of 5 or greater was able to correctly distinguish ARVD/C from idiopathic VT 93% of the time, with a sensitivity of 84%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 91%. We describe a simple scoring algorithm that uses 12-lead electrocardiogram characteristics to effectively distinguish right ventricular outflow tract arrhythmias originating from patients with ARVD/C versus patients with idiopathic VT. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
A flash from the past: a case on long term follow-up of a "corridor" operation.
Ricciardi, Danilo; Sarkozy, Andrea; Wauters, Kristel; Brugada, Pedro
2013-01-01
An electrophysiological study in a patient with a previous corridor operation was performed because of syncope. The atrial electrograms showed the persistence of the sinus rhythm in the right atrial corridor despite an organized atrial fibrillation in the left atrium. The first case described of a long term follow-up in a corridor operation, one of the first described surgical approach for the treatment of atrial fibrillation, that gave the beginning to the non-pharmacological approach of this arrhythmia. Copyright © 2013 Elsevier Inc. All rights reserved.
Vagal tone as an index of mental state
NASA Technical Reports Server (NTRS)
Porges, Stephen W.
1988-01-01
The utility of monitoring oscillations in the heart rate pattern as a window to the brain is discussed as an index of general central nervous system status. Quantification of the amplitude of respiratory sinus arrhythmia provides an accurate index of cardiac vagal tone. A number of studies have demonstrated the validity of this measure; the relationship between flight performance and vagal tone has also been studied. In general, the vagal tone index appears to monitor global states of the central nervous system and may be useful in screening the general state of pilots.
Emmel, M; Sreeram, N; Brockmeier, K
2005-04-01
Idiopathic junctional ectopic tachycardia is a rare arrhythmia in children. Several studies have demonstrated that drug therapy is often ineffective and sometimes the only achieved effect is rate control. Early presentation and frequent recurrence are associated with adverse outcome. Three consecutive children, aged 9, 7 and 12 years respectively, underwent radiofrequency catheter ablation for junctional ectopic tachycardia, after having failed antiarrhythmic drug therapy. The entire His bundle was plotted out and marked, using the Localisa navigation system. The arrhythmia was readily and repeatedly inducible using intravenous isoprenaline infusion and the site of earliest retrograde conduction during tachycardia could be assessed. Ablations were performed in sinus rhythm, empirically targeting the site of earliest retrograde conduction during tachycardia. This approach was successful in abolishing tachyarrhythmia in the first two patients, in whom the successful ablation site was located superoparaseptally. In the third patient, junctional ectopic tachycardia was inducible, despite abolishing retrograde atrial activation, in a septal location on the tricuspid valve annulus. Further ablations in the superoparaseptal region, closer to the His bundle, were successful in rendering tachyarrhythmia noninducible. Over a median follow-up of 10 months, none of the patients has had recurrence of arrhythmia, despite discontinuing all antiarrhythmic medications. Radio frequency catheter ablation of junctional ectopic tachycardia is feasible with preservation of atrioventricular conduction.
Prabhu, Mukund A; Thajudeen, Anees; Vk, Ajit Kumar; J, Tharakan; B V, Prasad Srinivas; Namboodiri, Narayanan
2017-01-01
Left atrial (LA) reentrant tachycardias are not uncommon in regions where rheumatic heart disease is prevalent. Some of these arrhythmias may be curable by radiofrequency ablation (RFA). However, there are limited data pertaining to this in existing literature. Three patients who had rheumatic mitral valve disease with past history of surgical-/catheter-based intervention and having no significant residual disease had symptomatic atrial flutter despite optimal medical management. An electrophysiological study confirmed an LA focal/micro-reentrant mechanism in all. There was patchy scarring of the LA, and successful RFA of these arrhythmias could be achieved. The focal nature of the scar in these patients may suggest that the rheumatic involvement of the atrium or the hemodynamic consequence of the vulvar lesion causes nonuniform insult to the atrial tissue and limited scar. At least in some patients with limited scarring, early RFA may help in the maintenance of sinus rhythm. © 2016 Wiley Periodicals, Inc.
CONRADT, ELISABETH; BEAUCHAINE, THEODORE; ABAR, BEAU; LAGASSE, LINDA; SHANKARAN, SEETHA; BADA, HENRIETTA; BAUER, CHARLES; WHITAKER, TONI; HAMMOND, JANE; LESTER, BARRY
2016-01-01
There is a growing scientific interest in the psychophysiological functioning of children living in low-socioeconomic status (SES) contexts, though this research is complicated by knowledge that physiology–behavior relations often operate differently in these environments among adults. Importantly, such research is made more difficult because SES may be a proxy for a wide range of risk factors including poor caregiving and exposure to parental substance use. We used factor analysis to organize risk-exposure data collected from 827 children—many of whom were raised in low-SES contexts and exposed to substances prenatally—into dissociable components including economic stress, caregiving stress (e.g., stress the caregiver may experience, including parental psychopathology), and postnatal substance exposure. These factors, along with respiratory sinus arrhythmia (RSA) reactivity at age 1 month, were used to predict behavior dysregulation and resting RSA at age 3 years. A significant RSA Reactivity × Caregiving Stress interaction indicated that infants who exhibited high RSA reactivity at 1 month experienced the greatest behavior dysregulation at 3 years, but only when they were exposed to high levels of caregiving stress. Among African Americans, the highest resting RSA at 3 years was found in infants with less RSA reactivity, but only if they also experienced less caregiving stress. Our work is consistent with biological sensitivity to context, adaptive calibration, and allostatic load models, and highlights the importance of studying Physiology × Environment interactions in low-SES contexts for predicting behavior and resting RSA. PMID:26681620
Conradt, Elisabeth; Degarmo, David; Fisher, Phil; Abar, Beau; Lester, Barry M.; Lagasse, Linda L.; Shankaran, Seetha; Bada, Henrietta; Bauer, Charles R.; Whitaker, Toni M.; Hammond, Jane A.
2015-01-01
Neurobehavioral disinhibition (ND) is a complex condition reflecting a wide range of problems involving difficulties with emotion regulation and behavior control. Respiratory sinus arrhythmia (RSA) is a physiological correlate of emotion regulation that has been studied in a variety of at-risk populations; however, there are no studies of RSA in children with ND. Data were drawn from a prospective longitudinal study of prenatal substance exposure that included 1,073 participants. Baseline RSA and RSA reactivity to an attention-demanding task were assessed at 3, 4, 5, and 6 years. ND was assessed at ages 8/9, 11, and 13/14 years via behavioral dysregulation and executive dysfunction composite measures. Greater exposure to early adversity was related to less RSA reactivity at 3 years, increases in RSA reactivity from ages 3 to 6 years, and increased behavioral dysregulation from ages 8/9 to 13/14. RSA reactivity was examined as a moderator of the association between early adversity and changes in ND. A significant Early Adversity × RSA Reactivity quadratic interaction revealed that children with decelerations in RSA reactivity exhibited increases in behavioral dysregulation, regardless of their exposure to early adversity. However, greater exposure to early adversity was related to greater increases in behavioral dysregulation, but only if children exhibited accelerations in RSA reactivity from ages 3 to 6 years. The results contribute to our understanding of how interactions across multiple levels of analysis contribute to the development of ND. PMID:24909973
Mathewson, Karen J; Schmidt, Louis A; Miskovic, Vladimir; Santesso, Diane L; Duku, Eric; McCabe, Randi E; Antony, Martin M; Moscovitch, David A
2013-05-01
Modifying dysfunctional emotion regulation is an important goal in psychological treatments for social anxiety disorder (SAD). Antecedent-focused strategies learned in cognitive behavioral therapy (CBT), such as cognitive reappraisal, have proven more effective in reducing social anxiety than response-focused strategies, such as expressive suppression. Still, not all patients with SAD respond well to CBT. Medications and physiological factors may also influence the clinical response. The purpose of the present study was to examine the role that these factors play in determining treatment response following CBT for SAD. Using multilevel modeling, we examined associations across four separate laboratory visits between change in self-reported anxiety and indices of reappraisal, suppression, medication status, and resting respiratory sinus arrhythmia (RSA), a proxy measure of self-regulatory capacity, in 23 socially anxious adults during a 12-week program of CBT. Most participants were ultimately classified as responders to CBT (n=15), but in some, anxiety levels remained unchanged (n=8). Medication use explained substantial variance related to individual differences in anxiety among participants. When modeled separately, reappraisal, suppression, and RSA each accounted for significant variance related to anxiety. However, the best-fitting model included reappraisal and RSA. Moreover, RSA reactivity (change in RSA levels over time) was more important for predicting anxiety reduction than were baseline levels of RSA. These findings suggest that reappraisal and parasympathetic responsiveness may be important in reducing anxiety in adults with SAD who respond well to CBT. Copyright © 2013 Elsevier B.V. All rights reserved.
Vagal and sympathetic activity in burnouts during a mentally demanding workday.
Zanstra, Ydwine J; Schellekens, Jan M H; Schaap, Cas; Kooistra, Libbe
2006-01-01
We study differences in task performance and related sympathetic-vagal reaction patterns between burnouts and controls during a mentally demanding workday. Thirty-nine adults with burnout and 40 healthy controls performed mental tasks during a simulated workday. At pretest, just before lunch (lunch test) and at the end of the day (posttest), a Stroop color word task was administered as a probe task. Efficiency (the relation between performance and effort during the probe task), performance (reaction time and errors), and effort (self-report) were measured, as well as cardiovascular indices of sympathetic (blood pressure) and vagal (respiratory sinus arrhythmia) activity. Performance and effort investment of both burnouts and controls did not differ during pretest. As the day progressed the performance of controls improved more than the performance of burnouts. Moreover, the control group showed a decrease of blood pressure in response to mental task demands, a decrease in respiratory sinus arrhythmia activity, and no change in experienced effort. In the burnout group, no change could be demonstrated in blood pressure, suggesting a sympathetic predominance in the sympathetic-vagal balance. Burnouts experienced an increase in effort and were more tired at the end of the workday. Burnouts and healthy controls differ in their pattern of sympathetic-vagal activity only after long-lasting work demands. Findings give limited support to Porges's view that in healthy subjects, the vagal system is more responsive to challenging task situations than in chronically stressed individuals. The distinction between two phases in the burnout on the basis of behavioral and physiological characteristics is discussed.
[Comprehensive testing system for cardiorespiratory interaction research].
Zhang, Zhengbo; Wang, Buqing; Wang, Weidong; Zheng, Jiewen; Liu, Hongyun; Li, Kaiyuan; Sun, Congcong; Wang, Guojing
2013-04-01
To investigate the modulation effects of breathing movement on cardiovascular system and to study the physiological coupling relationship between respiration and cardiovascular system, we designed a comprehensive testing system for cardiorespiratory interaction research. This system, comprising three parts, i. e. physiological signal conditioning unit, data acquisition and USB medical isolation unit, and a PC based program, can acquire multiple physiological data such as respiratory flow, rib cage and abdomen movement, electrocardiograph, artery pulse wave, cardiac sounds, skin temperature, and electromyography simultaneously under certain experimental protocols. Furthermore this system can be used in research on short-term cardiovascular variability by paced breathing. Preliminary experiments showed that this system could accurately record rib cage and abdomen movement under very low breathing rate, using respiratory inductive plethysmography to acquire respiration signal in direct-current coupling mode. After calibration, this system can be used to estimate ventilation non-intrusively and correctly. The PC based program can generate audio and visual biofeedback signal, and guide the volunteers to perform a slow and regular breathing. An experiment on healthy volunteers showed that this system was able to guide the volunteers to do slow breathing effectively and simultaneously record multiple physiological data during the experiments. Signal processing techniques were used for off-line data analysis, such as non-invasive ventilation calibration, QRS complex wave detection, and respiratory sinus arrhythmia and pulse wave transit time calculation. The experiment result showed that the modulation effect on RR interval, respiratory sinus arrhythmia (RSA), pulse wave transit time (PWTT) by respiration would get stronger with the going of the slow and regular breathing.
Kuo, Janice R; Fitzpatrick, Skye; Metcalfe, Rebecca K; McMain, Shelley
2016-03-01
Borderline personality disorder (BPD) is conceptualized as a disorder of heightened emotional reactivity and difficulties with emotion regulation. However, findings regarding emotional reactivity in BPD are mixed and there are limited studies examining emotion regulation capabilities in this population. Twenty-five individuals with BPD and 30 healthy controls (HCs) engaged in a baseline assessment followed by the presentation of neutral and BPD-relevant negative images. Participants were instructed to react as they naturally would to the image, or to use a mindfulness-based or distraction-based strategy to feel less negative. Self-reported and physiological (i.e., heart rate, electrodermal activity, and respiratory sinus arrhythmia) measures were collected. Compared with the HCs, the BPD group exhibited elevated heart rate and reduced respiratory sinus arrhythmia at baseline. However, there were no differences in emotional reactivity in self-report or physiological indices between the two groups. In addition, the BPD group did not exhibit deficits in the ability to implement either emotion regulation strategy, with the exception that the BPD group reported less positive emotions while distracting compared with the HCs. This study is limited by a small sample size and the inclusion of a medicated BPD sample. Emotion dysregulation in BPD might be better accounted for by abnormal baseline emotional functioning rather than heightened emotional reactivity or deficits in emotion regulation. Treatments for BPD might be enhanced by directly targeting resting state emotional functioning rather than emotional reactions or regulatory attempts. Copyright © 2015 Elsevier Ltd. All rights reserved.
Munafò, Marianna; Patron, Elisabetta; Palomba, Daniela
2016-06-01
High work stress has been consistently associated with disturbed autonomic balance, specifically, lowered vagal cardiac control and increased sympathetic activity, which may lead to increased cardiovascular risk. Stress management procedures have been proposed to reduce autonomic dysfunctions related to work stress in different categories of workers exposed to heightened work demands, while a limited number of studies addressed this issue in managers. The present study was aimed at evaluating the effectiveness of a respiratory sinus arrhythmia (RSA) biofeedback (BF) intervention on psychological and physiological outcomes, in managers with high-level work responsibilities. Thirty-one managers leading outstanding private or public companies were randomly assigned to either a RSA-BF training (RSA-BF; N = 16) or a control group (N = 15). The RSA-BF training consisted of five weekly 45 min sessions, designed to increase RSA, whereas controls had to provide a daily stress diary once a week. After the training, managers in both groups reported reduced heart rate at rest, lower anxiety levels and improvement in health-related quality of life. More importantly, managers in the RSA-BF group showed increased vagal control (as indexed by increased RSA), decreased sympathetic arousal (as indexed by reduced skin conductance and systolic blood pressure) and lower emotional interferences, compared to managers in the control group. Results from this study showed that RSA-BF training was effective in improving cardiac autonomic balance at rest. Moreover, findings from this study underline the effectiveness of biofeedback in reducing psychophysiological negative outcomes associated with stress in managers.
Sivakumar, Siddharth S.; Namath, Amalia G.; Tuxhorn, Ingrid E.; Lewis, Stephen J.
2016-01-01
We hypothesized that epilepsy affects the activity of the autonomic nervous system even in the absence of seizures, which should manifest as differences in heart rate variability (HRV) and cardiac cycle. To test this hypothesis, we investigated ECG traces of 91 children and adolescents with generalized epilepsy and 25 neurologically normal controls during 30 min of stage 2 sleep with interictal or normal EEG. Mean heart rate (HR) and high-frequency HRV corresponding to respiratory sinus arrhythmia (RSA) were quantified and compared. Blood pressure (BP) measurements from physical exams of all subjects were also collected and analyzed. RSA was on average significantly stronger in patients with epilepsy, whereas their mean HR was significantly lower after adjusting for age, body mass index, and sex, consistent with increased parasympathetic tone in these patients. In contrast, diastolic (and systolic) BP at rest was not significantly different, indicating that the sympathetic tone is similar. Remarkably, five additional subjects, initially diagnosed as neurologically normal but with enhanced RSA and lower HR, eventually developed epilepsy, suggesting that increased parasympathetic tone precedes the onset of epilepsy in children. ECG waveforms in epilepsy also displayed significantly longer TP intervals (ventricular diastole) relative to the RR interval. The relative TP interval correlated positively with RSA and negatively with HR, suggesting that these parameters are linked through a common mechanism, which we discuss. Altogether, our results provide evidence for imbalanced autonomic function in generalized epilepsy, which may be a key contributing factor to sudden unexpected death in epilepsy. PMID:26888110
Initial Experience With Ultra High-Density Mapping of Human Right Atria.
Bollmann, Andreas; Hilbert, Sebastian; John, Silke; Kosiuk, Jedrzej; Hindricks, Gerhard
2016-02-01
Recently, an automatic, high-resolution mapping system has been presented to accurately and quickly identify right atrial geometry and activation patterns in animals, but human data are lacking. This study aims to assess the clinical feasibility and accuracy of high-density electroanatomical mapping of various RA arrhythmias. Electroanatomical maps of the RA (35 partial and 24 complete) were created in 23 patients using a novel mini-basket catheter with 64 electrodes and automatic electrogram annotation. Median acquisition time was 6:43 minutes (0:39-23:05 minutes) with shorter times for partial (4.03 ± 4.13 minutes) than for complete maps (9.41 ± 4.92 minutes). During mapping 3,236 (710-16,306) data points were automatically annotated without manual correction. Maps obtained during sinus rhythm created geometry consistent with CT imaging and demonstrated activation originating at the middle to superior crista terminalis, while maps during CS pacing showed right atrial activation beginning at the infero-septal region. Activation patterns were consistent with cavotricuspid isthmus-dependent atrial flutter (n = 4), complex reentry tachycardia (n = 1), or ectopic atrial tachycardia (n = 2). His bundle and fractionated potentials in the slow pathway region were automatically detected in all patients. Ablation of the cavotricuspid isthmus (n = 9), the atrio-ventricular node (n = 2), atrial ectopy (n = 2), and the slow pathway (n = 3) was successfully and safely performed. RA mapping with this automatic high-density mapping system is fast, feasible, and safe. It is possible to reproducibly identify propagation of atrial activation during sinus rhythm, various tachycardias, and also complex reentrant arrhythmias. © 2015 Wiley Periodicals, Inc.
Persistent Atrial Fibrillation Ablation using the Tip-Versatile Ablation Catheter.
Davies, Edward J; Clayton, Ben; Lines, Ian; Haywood, Guy A
2016-07-01
The mechanisms by which persistent atrial fibrillation (PsAF) develops are incompletely understood. Consequently, the optimal strategy for the ablative management of PsAF remains debated. Current methods are often time consuming, complex and non-reproducible. We assessed the Tip-Versatile Ablation Catheter (T-VAC) technique, a rapidly delivered, empirical technique based on the box-set concept using duty-cycled linear catheter ablation technology. Forty-four procedures in 40 patients undergoing PsAF ablation with the novel technique were prospectively entered onto a database: 27 de novo. Primary endpoint was freedom from arrhythmia at over two-year follow-up. Secondary endpoints were time to first arrhythmia recurrence, freedom from atrial fibrillation (AF) on and off antiarrhythmic drugs (AAD), procedural and fluoroscopy duration and complication rate. At mean follow-up of 33 months, absolute freedom from arrhythmia recurrence was 45% in the de novo group. Overall, at 33 (IQR 24-63) months, 60% of de novo patients were in sustained normal sinus rhythm and a further 15% reported only occasional paroxysms of AF at long-term follow-up. Procedure time was 192±25 mins, total energy delivered 2239±883s and fluoroscopy time was 60±10mins. In selected patients with persistent AF, a long-term rate of 60% arrhythmia free survival off AAD can be achieved using this novel T-VAC technique. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.
Lelakowski, Jacek; Majewski, Jacek; Małecka, Barbara; Bednarek, Jacek; Stypuła, Paweł; Szeglowski, Marcin
2007-01-01
During implantation of a DDD pacemaker the following difficulties may be encountered: venous anomalies (the absence of vessels of adequate calibre or difficulty in subclavian vein puncture), arrhythmias during implantation (episodes of atrial flutter/fibrillation while the atrial leads are being positioned), lack of mechanical stability of the electrode in the heart chamber and inability to achieve an acceptable pacing and sensing threshold during implantation. The purpose of the study was to analyse retrospectively the reasons for DDD pacemaker failure in patients operated on between 1993 and 2005. We reviewed retrospectively all implantation data from 1988 to 2005 to identify patients with primary failure of DDD pacemaker implantation. Further analysis included patients who had received a DDD pacemaker between 1993 and 2005, when this type of pacemaker made up between 9 and 40% of all pacemaker implantations. We implanted 7469 pacemakers, including 1958 (26.2%) dual-chamber pacemakers, in 783 patients with atrioventricular block (AVB), 392 with sick sinus syndrome (SSS), 450 with AVB +/- SSS and 333 with tachy-brady syndrome (TBS). The mean age of the patients was 65.5 +/- 17.3 years. DDD pacing was unsuccessful in 108 (1.4%) patients, including 32 with AVB, 22 with SSS, 16 with SSS +/- AVB and 38 with TBS. The mean age of these patients was 78.5 +/- 19.4 years. The reasons for failed implantation were venous anomalies in 12%, an arrhythmia episode in 27.8%, a high pacing threshold in the atrium in 17.6%, low atrial potential amplitude in 25.9% and lack of mechanical stability of the electrode in 16.7% of patients. The difficulties were encountered in elderly patients (p < 0.01), most frequently in patients with SSS and TBS (71). Between 2004 and 2005 venous anomalies and a high pacing threshold were the main causes of failure. Currently the main difficulties encountered during pacemaker implantation are venous anomalies and a high pacing threshold. Arrhythmia episodes, low atrial potential amplitude and lack of mechanical stability are of minor importance. Elderly patients with sick sinus syndrome and tachy-brady syndrome have the highest failure rate. (Cardiol J 2007; 14: 155-159).
A benefit-risk assessment of class III antiarrhythmic agents.
Brendorp, Bente; Pedersen, Oledyg; Torp-Pedersen, Christian; Sahebzadah, Naji; Køber, Lars
2002-01-01
With beta-blockers as the exception, increasing doubt is emerging on the value of antiarrhythmic drug therapy following a series of trials that have either shown no mortality benefit or even an excess mortality. Vaughan Williams class I drugs are generally avoided in patients with structural heart disease, and class IV drugs are avoided in heart failure. Unfortunately, arrhythmias are a growing problem due to an increase in the incidence of atrial fibrillation and sudden death. The population is becoming older and more patients survive for a longer time period with congestive heart failure, which again increases the frequency of both supraventricular as well as ventricular arrhythmias. Class III antiarrhythmic drugs act by blocking repolarising currents and thereby prolong the effective refractory period of the myocardium. This is believed to facilitate termination of re-entry tachyarrhythmias. This class of drugs is developed for treatment of both supraventricular and ventricular arrhythmias. Amiodarone, sotalol, dofetilide, and ibutilide are examples of class III drugs that are currently available. Amiodarone and sotalol have other antiarrhythmic properties in addition to pure class III action, which differentiates them from the others. However, all have potential serious adverse events. Proarrhythmia, especially torsade de pointes, is a common problem making the benefit-risk ratio of these drugs a key question. Class III drugs have been evaluated in different settings: primary and secondary prevention of ventricular arrhythmias and in treatment of atrial fibrillation or flutter. Based on existing evidence there is no routine indication for antiarrhythmic drug therapy other than beta-blockers in patients at high risk of sudden death. Subgroup analyses of trials with amiodarone and dofetilide suggest that patients with atrial fibrillation may have a mortality reduction with these drugs. However, this needs to be tested in a prospective trial. Similarly, subgroups that will benefit from prophylactic treatment with class III antiarrhythmic drugs may be found based on QT-intervals or - in the future - from genetic testing. Class III drugs are effective in converting atrial fibrillation to sinus rhythm and for the maintenance of sinus rhythm after conversion. This is currently by far the most important indication for this class of drugs. As defined by recent guidelines, amiodarone and dofetilide have their place as second-line therapy except for patients with heart failure where they are first line therapy being the only drugs where the safety has been documented for this group of high risk patients.
Panduranga, Prashanth; Al-Farqani, Abdullah; Al-Rawahi, Najib
2012-11-01
A 10-year-old girl presented to the emergency department of a regional hospital with 1 episode of generalized tonic-clonic seizures. Postictal monitoring followed by a 12-lead electrocardiogram showed fast atrial fibrillation with intermittent wide QRS regular tachycardia. Immediately following this, her rhythm changed to wide QRS irregular tachycardia without hemodynamic compromise. She was suspected to have ventricular tachycardia and was treated with intravenous amiodarone with cardioversion to sinus rhythm. Subsequent electrocardiogram in sinus rhythm showed typical features of manifest Wolff-Parkinson-White (WPW) accessory pathway. This case illustrates the diagnostic and therapeutic dilemmas in patients with atrial fibrillation, wide QRS tachycardia, and undiagnosed WPW syndrome with antidromic conduction of atrial arrhythmias through the accessory pathway. Furthermore, this case demonstrates that undiagnosed wide QRS tachycardias need to be treated with drugs acting on the accessory pathway, thus keeping in mind underlying WPW syndrome as a possibility to avoid potentially catastrophic events.
Sudden cardiac arrest as a rare presentation of myxedema coma: case report.
Salhan, Divya; Sapkota, Deepak; Verma, Prakash; Kandel, Saroj; Abdulfattah, Omar; Lixon, Antony; Zwenge, Deribe; Schmidt, Frances
2017-01-01
Myxedema coma is a decompensated hypothyroidism which occurs due to long-standing, undiagnosed, or untreated hypothyroidism. Untreated hypothyroidism is known to affect almost all organs including the heart. It is associated with a decrease in cardiac output, stroke volume due to decreased myocardial contractility, and an increase in systemic vascular resistance. It can cause cardiac arrhythmias and the most commonly seen conduction abnormalities are sinus bradycardia, heart block, ventricular tachycardia, and torsade de pointes. The authors report a case of an elderly man who presented with sudden cardiac arrest and myxedema coma and who was successfully revived.
Complete A-V block: incidental or a part of cor triatriatum dexter.
Guler, Y; Akgun, T; Toprak, C; Guler, A; Esen, A M
2014-05-01
Cor triatriatum dexter (CTD) is an extremely rare cardiac anomaly in which the right atrium is divided into two distinct chambers by a membrane. The persistence of the right valve of sinus venosus results in a complete septation of the right atrium. This anomaly is frequently associated with other right-sided cardiac abnormalities. Its clinical manifestation and the need for intervention are determined by the number and the size of the fenestrations on the membrane, associated cardiac anomalies and arrhythmias. We describe a case of CTD in a patient with complete atrioventricular (A-V) block.
Schwarz, Simon; Ravens, Ursula; Knaut, Michael
2016-01-01
Abstract Background and Purpose 5‐HT increases force and L‐type Ca2 + current (ICa,L) and causes arrhythmias through 5‐HT4 receptors in human atrium. In permanent atrial fibrillation (peAF), atrial force responses to 5‐HT are blunted, arrhythmias abolished but ICa,L responses only moderately attenuated. We investigated whether, in peAF, this could be due to an increased function of PDE3 and/or PDE4, using the inhibitors cilostamide (300 nM) and rolipram (1 μM) respectively. Experimental Approach Contractile force, arrhythmic contractions and ICa,L were assessed in right atrial trabeculae and myocytes, obtained from patients with sinus rhythm (SR), paroxysmal atrial fibrillation (pAF) and peAF. Key Results Maximum force responses to 5‐HT were reduced to 15% in peAF, but not in pAF. Cilostamide, but not rolipram, increased both the blunted force responses to 5‐HT in peAF and the inotropic potency of 5‐HT fourfold to sevenfold in trabeculae of patients with SR, pAF and peAF. Lusitropic responses to 5‐HT were not decreased in peAF. Responses of ICa,L to 5‐HT did not differ and were unaffected by cilostamide or rolipram in myocytes from patients with SR or peAF. Concurrent cilostamide and rolipram increased 5‐HT's propensity to elicit arrhythmias in trabeculae from patients with SR, but not with peAF. Conclusions and Implications PDE3, but not PDE4, reduced inotropic responses to 5‐HT in peAF, independently of lusitropy and ICa,L, but PDE3 activity was the same as that in patients with SR and pAF. Atrial remodelling in peAF abolished the facilitation of 5‐HT to induce arrhythmias by inhibition of PDE3 plus PDE4. PMID:27238373
Cardiac arrhythmias during aerobatic flight and its simulation on a centrifuge.
Zawadzka-Bartczak, Ewelina K; Kopka, Lech H
2011-06-01
It is well known that accelerations during centrifuge training and during flight can provoke cardiac arrhythmias. Our study was designed to investigate both the similarities and differences between heart rhythm disturbances during flights and centrifuge tests. There were 40 asymptomatic, healthy pilots who performed two training flights and were also tested in a human centrifuge according to a program of rapid onset rate acceleration (ROR) and of centrifuge simulation of the actual acceleration experienced in flight (Simulation). During the flight and centrifuge tests ECG was monitored with the Holter method. ECG was examined for heart rhythm changes and disturbances. During flights, premature ventricular contractions (PVCs) were found in 25% of the subjects, premature supraventricular contractions (PSVCs) and PVCs with bigeminy in 5%, and pairs of PVCs in 2.5% of subjects. During the centrifuge tests, PVCs were experienced by 45% of the subjects, PSVCs and pairs of PVCs by 7.5%, and PVCs with bigeminy by 2.5%. Sinus bradycardia was observed during flights and centrifuge tests in 7.5% of subjects. Comparative evaluation of electrocardiographic records in military pilots during flights and centrifuge tests demonstrated that: 1) there were no clinically significant arrhythmias recorded; and 2) the frequency and kind of heart rhythm disturbances during aerobatic flight and its simulation on a centrifuge were not identical and did not occur repetitively in the same persons during equal phases of the tests.
Twenty-four hour Holter monitoring in finishing cattle housed outdoors.
Frese, D A; Thomason, J D; Reinhardt, C; Bartle, S; Rethorst, D; Loneragan, G H; Thomson, D
2017-04-01
Atrial premature complexes have been reported to be the most common arrhythmia in cattle and is suspected to be secondary to systemic disease, especially gastrointestinal disease. In order to properly identify pathologic arrhythmia in cattle, the normal rhythm and arrhythmia prevalence should be defined. The objective of this study was to determine the normal heart rate, rhythm, number of ventricular premature complexes (VPCs), and atrial premature complexes (APCs) in unrestrained Angus steers. Twenty-seven client owned steers with unremarkable physical examinations and serum biochemical analyses were used. Twenty-four hour Holter monitors, attached by a custom-made harness, were retrospectively evaluated. Three lead electrocardiographic registrations of good quality and normal sinus rhythm were obtained from all steers in the study. The mean heart rate was 66.8 bpm ± 16.4 bpm. Ventricular premature complexes were rare (noted in 14.8% of steers), and APCs were common (noted in 85% of the steers). Simple second degree AV block was observed in 18.5% of the steers. In summary, healthy steers have rare single VPCs, although it is possible for an individual animal to have apparent more frequent VPCs. Mean heart rate varies with a diurnal pattern similar to other species. Atrial premature complexes are the most prevalent abnormality observed in feedlot steers. Copyright © 2016 Elsevier B.V. All rights reserved.
The use of sugammadex in a pregnant patient with Wolff-Parkinson-White syndrome.
Sengul, Turker; Saracoglu, Ayten; Sener, Sibel; Bezen, Olgac
2016-09-01
Wolff-Parkinson-White (WPW) syndrome is a rare pre-excitation syndrome which develops when atrioventricular conduction occurs through a pathologic accessory pathway known as the bundle of Kent instead of atrioventricular node, hence resulting in tachycardia. Patients with WPW syndrome may experience various symptoms arising from mild-to-moderate chest disease, palpitations, hypotension, and severe cardiopulmonary dysfunction. These patients are most often symptomatic because of cardiac arrhythmias. In this case report, we present an uneventful anesthetic management of a pregnant patient with WPW syndrome undergoing cesarean delivery. A 23-year-old American Society of Anesthesiologists class 2 pregnant patient was diagnosed with WPW syndrome. Her preoperative 12-lead electrocardiogram showed a sinus rhythm at 82 beats per minute, a delta wave, and a short PR interval. After an uneventful surgery, sugammadex 2mg/kg was administered as a reversal agent instead of neostigmine. Then she was discharged to her obstetrics service. Serious hemodynamic disorders may occur in patients with WPW syndrome due to development of fatal arrhythmias. Neostigmine used as a reversal agent in general anesthesia can trigger such fatal arrhythmias by leading changes in cardiac conduction. We believe that sugammadex, which is safely used in many areas in the scope of clinical practice, can be also used for patients diagnosed with WPW syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.
PULSESMART: Pulse-based Arrhythmia Discrimination Using a Novel Smartphone Application
McManus, David D.; Chong, Jo Woon; Soni, Apurv; Saczynski, Jane S.; Esa, Nada; Napolitano, Craig; Darling, Chad E.; Boyer, Edward; Rosen, Rochelle K.; Floyd, Kevin C.; Chon, Ki H.
2015-01-01
Background Atrial fibrillation (AF) is a common and dangerous paroxysmal rhythm abnormality. Smartphones are increasingly used for mobile health applications by older patients at risk for AF and may be useful for AF screening. Objectives To test whether an enhanced smartphone app for AF detection can discriminate between sinus rhythm (SR), AF, premature atrial contractions (PACs) and premature ventricular contractions (PVCs). Methods We analyzed 219 2-minute pulse recordings from 121 participants with AF (n=98), PACs (n=15), or PVCs (n=15) using an iPhone 4S. We obtained pulsatile time series recordings in 91 participants after successful cardioversion to sinus rhythm from pre-existing AF. The PULSESMART app conducted pulse analysis using 3 methods [Root Mean Square of Successive RR Differences; Shannon Entropy; Poincare plot]. We examined the sensitivity, specificity, and predictive accuracy of the app for AF, PAC, and PVC discrimination from sinus rhythm using the 12-lead EKG or 3-lead telemetry as the gold standard. We also administered a brief usability questionnaire to a subgroup (n=65) of app users. Results The smartphone-based app demonstrated excellent sensitivity (0.970), specificity (0.935), and accuracy (0.951) for real-time identification of an irregular pulse during AF. The app also showed good accuracy for PAC (0.955) and PVC discrimination (0.960). The vast majority of surveyed app users (83%) reported that it was “useful” and “not complex” to use. Conclusions A smartphone app can accurately discriminate pulse recordings during AF from sinus rhythm, PACs, and PVCs. PMID:26391728
Zhang, Wei; Fagan, Shawn E.; Gao, Yu
2017-01-01
Atypical respiratory sinus arrhythmia (RSA), a biomarker of emotion dysregulation, is associated with both externalizing and internalizing behaviors. In addition, social adversity and gender may moderate this association. In this study, we investigated if RSA (both resting RSA and RSA reactivity in an emotion regulation task) predicts externalizing and/or internalizing behaviors and the extent to which social adversity moderates this relationship. Two hundred and fifty-three children (at Time 1, mean age = 9.05, SD = 0.60, 48% boys) and their caregivers from the community participated in this study. Resting RSA and RSA reactivity were assessed, and caregivers reported children’s externalizing and internalizing behaviors at both Time 1 and Time 2 (1 year later). We found that lower resting RSA (but not RSA reactivity) at Time 1 was associated with increased externalizing and internalizing behaviors at Time 2 in boys, even after controlling for the effects of Time 1 behavioral problems and Time 2 age. Moreover, there was a significant interaction effect between Time 1 resting RSA and social adversity such that lower resting RSA predicted higher externalizing and internalizing behaviors in boys only under conditions of high social adversity. Follow-up analyses revealed that these predictive effects were stronger for externalizing behavior than for internalizing behavior. No significant effects were found for girls. Our findings provide further evidence that low resting RSA may be a transdiagnostic biomarker of emotion dysregulation and a predisposing risk factor for both types of behavior problems, in particular for boys who grow up in adverse environments. We conclude that biosocial interaction effects and gender differences should be considered when examining the etiological mechanisms of child psychopathology. PMID:28955262
Palmieri, Vincenzo; Gervasi, Salvatore; Bianco, Massimiliano; Cogliani, Roberta; Poscolieri, Barbara; Cuccaro, Francesco; Marano, Riccardo; Mazzari, Mario; Basso, Cristina; Zeppilli, Paolo
2018-02-01
Although anomalous origin of left (AOLCA) and right coronary artery (AORCA) from the wrong sinus may cause sudden death (SD) in athletes, early diagnosis and management of these anomalies are still challenging. We analysed clinical/instrumental profiles of athletes identified with AOLCA/AORCA focusing our attention on diagnosis, management and follow-up. We report 23 athletes (17 males, mean age 27±17yrs.), 6 with AOLCA and 17 with AORCA. Diagnosis was made by trans-thoracic echocardiography (TTE) in 21/23(91%). Symptoms were present only in 10(41%). Only 3 had an abnormal rest-ECG and 9(39%) an abnormal stress test ECG (3 ST-depression, 4 ventricular arrhythmias, 1 supraventricular arrhythmias, 1 rate-dependent left-bundle-branch-block). Anatomy of the anomalous coronary artery showed no significant correlation with clinical presentation, except for a tendency to higher occurrence of proximal hypoplasia in symptomatic athletes (83% vs 40%, p=0.09). All athletes were disqualified from competitive-sports and advised to avoid strenuous effort. Surgery was recommended to all athletes with AOLCA and 6 with AORCA, but only 6 underwent surgery. No major cardiac events or ischemic symptoms/signs occurred during a mean follow-up of 65±70months. Early diagnosis of AOLCA/AORCA in athletes is feasible by TTE. Typical symptoms/signs of myocardial ischemia are present only in one third of cases thus underlying the need of a high index of clinical suspicion to achieve the diagnosis. After exercise restriction, none had major cardiac events or ischemia symptoms/signs recurrence. There was no correlation between anatomical characteristics and clinical presentation with the possible exception of coronary hypoplasia. Copyright © 2017 Elsevier B.V. All rights reserved.
Elstad, Maja; Walløe, Lars; Holme, Nathalie L A; Maes, Elke; Thoresen, Marianne
2015-03-01
Arterial blood pressure variations are an independent risk factor for end organ failure. Respiratory sinus arrhythmia (RSA) is a sign of a healthy cardiovascular system. However, whether RSA counteracts arterial blood pressure variations during the respiratory cycle remains controversial. We restricted normal RSA with non-invasive intermittent positive pressure ventilation (IPPV) to test the hypothesis that RSA normally functions to stabilize mean arterial blood pressure. Ten young volunteers were investigated during metronome-paced breathing and IPPV. Heart rate (ECG), mean arterial blood pressure and left stroke volume (finger arterial pressure curve) and right stroke volume (pulsed ultrasound Doppler) were recorded, while systemic and pulmonary blood flow were calculated beat-by-beat. Respiratory variations (high-frequency power, 0.15-0.40 Hz) in cardiovascular variables were estimated by spectral analysis. Phase angles and correlation were calculated by cross-spectral analysis. The magnitude of RSA was reduced from 4.9 bpm(2) (95% CI 3.0, 6.2) during metronome breathing to 2.8 bpm(2) (95% CI 1.1, 5.0) during IPPV (p = 0.03). Variations in mean arterial blood pressure were greater (2.3 mmHg(2) (95% CI 1.4, 3.9) during IPPV than during metronome breathing (1.0 mmHg(2) [95% CI 0.7, 1.3]) (p = 0.014). Respiratory variations in right and left stroke volumes were inversely related in the respiratory cycle during both metronome breathing and IPPV. RSA magnitude is lower and mean arterial blood pressure variability is greater during IPPV than during metronome breathing. We conclude that in healthy humans, RSA stabilizes mean arterial blood pressure at respiratory frequency.
'Non-hypotensive' hypovolaemia reduces ascending aortic dimensions in humans
NASA Technical Reports Server (NTRS)
Taylor, J. A.; Halliwill, J. R.; Brown, T. E.; Hayano, J.; Eckberg, D. L.
1995-01-01
1. The notion that small, 'non-hypotensive' reductions of effective blood volume alter neither arterial pressure nor arterial baroreceptor activity is pervasive in the experimental literature. We tested two hypotheses: (a) that minute arterial pressure and cardiac autonomic outflow changes during hypovolaemia induced by lower body suction in humans are masked by alterations in breathing, and (b) that evidence for arterial baroreflex engagement might be obtained from measurements of thoracic aorta dimensions. 2. In two studies, responses to graded lower body suction at 0 (control), 5, 10, 15, 20 and 40 mmHg were examined in twelve and ten healthy young men, respectively. In the first, arterial pressure (photoplethysmograph), R-R interval, and respiratory sinus arrhythmia amplitude (complex demodulation) were measured during uncontrolled and controlled breathing (constant breathing frequency and tidal volume). In the second, cross-sectional areas of the ascending thoracic aorta were calculated from nuclear magnetic resonance images. 3. Lower body suction with controlled breathing resulted in an increased arterial pulse pressure at mild levels (5-20 mmHg; ANOVA, P < 0.05) and a decreased arterial pulse pressure at moderate levels (40 mmHg; ANOVA, P < 0.05). Both R-R intervals and respiratory sinus arrhythmia were negatively related to lower body suction level, whether group averages (general linear regression, r > 0.92) or individual subjects (orthogonal polynomials, 12 of 12 subjects) were assessed. 4. Aortic pulse area decreased progressively and significantly during mild lower body suction, with 47% of the total decline occurring by 5 mmHg. 5. These results suggest that small reductions of effective blood volume reduce aortic baroreceptive areas and trigger haemodynamic adjustments which are so efficient that alterations in arterial pressure escape detection by conventional means.
Rusin, Craig G.; Hudson, John L.; Lee, Hoshik; Delos, John B.; Guin, Lauren E.; Vergales, Brooke D.; Paget-Brown, Alix; Kattwinkel, John; Lake, Douglas E.; Moorman, J. Randall
2012-01-01
In healthy neonates, connections between the heart and lungs through brain stem chemosensory pathways and the autonomic nervous system result in cardiorespiratory synchronization. This interdependence between cardiac and respiratory dynamics can be difficult to measure because of intermittent signal quality in intensive care settings and variability of heart and breathing rates. We employed a phase-based measure suggested by Schäfer and coworkers (Schäfer C, Rosenblum MG, Kurths J, Abel HH. Nature 392: 239–240, 1998) to obtain a breath-by-breath analysis of cardiorespiratory interaction. This measure of cardiorespiratory interaction does not distinguish between cardiac control of respiration associated with cardioventilatory coupling and respiratory influences on the heart rate associated with respiratory sinus arrhythmia. We calculated, in sliding 4-min windows, the probability density of heartbeats as a function of the concurrent phase of the respiratory cycle. Probability density functions whose Shannon entropy had a <0.1% chance of occurring from random numbers were classified as exhibiting interaction. In this way, we analyzed 18 infant-years of data from 1,202 patients in the Neonatal Intensive Care Unit at University of Virginia. We found evidence of interaction in 3.3 patient-years of data (18%). Cardiorespiratory interaction increased several-fold with postnatal development, but, surprisingly, the rate of increase was not affected by gestational age at birth. We find evidence for moderate correspondence between this measure of cardiorespiratory interaction and cardioventilatory coupling and no evidence for respiratory sinus arrhythmia, leading to the need for further investigation of the underlying mechanism. Such continuous measures of physiological interaction may serve to gauge developmental maturity in neonatal intensive care patients and prove useful in decisions about incipient illness and about hospital discharge. PMID:22174403
Busscher, Bert; Spinhoven, Philip; de Geus, Eco J C
2015-09-01
Exposure is regarded to be a crucial component of therapies for phobias. According to emotional processing theory, the success of exposure therapy is predicted by activation of subjective and physiological fear responses and their within-session habituation and between-session adaptation. This study tested this prediction for aviophobia. Seventy-nine participants following a highly standardized treatment program for aviophobia provided self-reported and physiological (heart rate, respiratory sinus arrhythmia and pre-ejection period) measurements of fear activation, within-session habituation, and between-session adaptation during exposure to flight-related stimuli, a flight simulator, and during two real flights. Multiple regression analyses were conducted to examine whether these measurements predicted therapy outcome up to 3 years after finishing therapy, including number of flights flown in this period. Both subjective and physiological arousal measurements indicated strong fear activation and large within-session habituation and between-session adaptation during exposure. Flight anxiety measures showed large improvements up to 3 years after treatment (η between 0.72 and 0.91). Lower self-reported anxiety during flight exposure was associated with lower flight anxiety after exposure (R = 0.15) and more flights flown (R = 0.14). Within-flight habituation or between-session adaptation of self-reported anxiety had no relationship with treatment outcome. Within-flight habituation of HR reactivity (R = 0.10) and respiratory sinus arrhythmia reactivity (R = 0.11) was associated with lower flight anxiety directly after the flight, but not on flight anxiety 3 years after finishing therapy or on long-term flying behavior. The results provide only weak support for emotional processing theory. Low self-reported anxiety during in vivo flight exposure was the best predictor of successful long-term therapy outcome.
[Risk of arrhythmia and domestic low-voltage electrical injury].
Claudet, I; Maréchal, C; Debuisson, C; Salanne, S
2010-04-01
Analysis of domestic low-voltage (220-240 V) electrical injury in children admitted to a pediatric emergency department to illustrate the low risk of initial or delayed risk of arrhythmia. Retrospective study between 2001 and 2008 analyzing all children aged less than 15 years admitted for a low-voltage electrical injury. The data collected were age, sex, time and circumstances of the accident, time and day of admission, transport modalities, presence of risk factors for arrhythmia (transthoracic current, wet skin, tetany, loss of consciousness or neurological symptoms, and initial EKG abnormalities), injuries, EKG, muscular and/or cardiac enzyme values, progression and complications. For statistical analysis, data were entered in Microsoft Excel tables. Analysis was done with StatView5.1 (SAS Institute) and Epi Info 6.04fr (VF, ENSP epiconcept). In the descriptive analysis, the data are presented as mean values with SD, median and range. Forty-eight children were included. The mean annual number of admissions was equal to 6 (range, 3-12). The mean age was 6.2 + or - 4.3 years (median, 4.6 years). There was a male predominance: the overall sex ratio was 1.5, i.e., 3 before the age of 2 and 2.6 before the age of 10. The electrical injury occurred after contact with a wire or a connected cord or after the introduction of a metallic object in a wall socket. Ten children had risk factors of arrhythmia (mainly wet skin or thoracic pain). Twenty-nine children suffered from burns to the extremities (digits and hands, 70 %). At admission, 45 children had an EKG performed. The initial EKG was considered abnormal in 8 cases showing: sinusal tachycardia (n=4), incomplete right bundle branch block (n=4), and V(1) negative T waves (n=1). The EKG normalized within the first 12h. Hospitalization for cardiac monitoring was required for 18 children. No delayed arrhythmia occurred. In a mean time of 3.5h after the accident, a troponin dosage was given to 15 children and was normal in all cases. One child developed rhabdomyolysis and evolved without needing dialysis. After a low-voltage electrical injury, initial arrhythmia is not frequent, with often a nonspecific and transitory EKG expression; delayed arrhythmia is very rare. Children presenting to the emergency department after such an electrical accident, who are asymptomatic, without any risk factors for arrhythmia (wet skin, tetany, vertical pathway of the current, preexistent cardiological conditions, loss of consciousness) and with a normal initial EKG do not require cardiac monitoring. Copyright 2010 Elsevier Masson SAS. All rights reserved.
Carbon monoxide and lethal arrhythmias
DOE Office of Scientific and Technical Information (OSTI.GOV)
Farber, J.P.; Schwartz, P.J.; Vanoli, E.
1990-12-01
The effect of acute exposure to carbon monoxide on ventricular arrhythmias was studied in a previously described chronically maintained animal model of sudden cardiac death. In 60 percent of dogs with a healed anterior myocardial infarction, the combination of mild exercise and acute myocardial ischemia induces ventricular fibrillation. The events in this model are highly reproducible, thus allowing study by internal control analysis. Dogs that develop ventricular fibrillation during the test of exercise and acute myocardial ischemia are considered at high risk for sudden death and are defined as 'susceptible'; dogs that survive the test without a fatal arrhythmia aremore » considered at low risk for sudden death and are defined as 'resistant.' In the current study, the effects of carboxyhemoglobin levels ranging from 5 to 15 percent were tested in resistant and susceptible dogs. A trend toward higher heart rates was observed at all levels of carboxyhemoglobin, although significant differences were observed only with 15 percent carboxyhemoglobin. This trend was observed at rest and during exercise in both resistant and susceptible dogs. In resistant animals, in which acute myocardial ischemia is typically associated with bradycardia even under the control condition, this reflex response occurred earlier and was augmented after exposure to carbon monoxide. This effect may depend on the increased hypoxic challenge caused by carbon monoxide, and thus on an augmentation of the neural reflex activation or a sensitization of the sinus node to acetylcholine induced by hypoxia. In both resistant and susceptible dogs, carbon monoxide exposure induced a worsening of ventricular arrhythmias in a minority of cases. This worsening was not reproducible in subsequent trials. These data indicate that acute exposure to carbon monoxide is seldom arrhythmogenic in dogs that have survived myocardial infarction. (Abstract Truncated)« less
Theis, Cathrin; Konrad, Torsten; Mollnau, Hanke; Sonnenschein, Sebastian; Kämpfner, Denise; Potstawa, Maik; Ocete, Blanca Quesada; Bock, Karsten; Himmrich, Ewald; Münzel, Thomas; Rostock, Thomas
2015-10-01
Pulmonary vein isolation (PVI) is still associated with a substantial number of arrhythmia recurrences in paroxysmal atrial fibrillation (AF). This prospective, randomized study aimed to compare 2 different procedural strategies. A total of 152 patients undergoing de novo ablation for paroxysmal AF were randomized to 2 different treatment arms. The procedure in group A consisted of PVI exclusively. In this group, all isolated PVs were challenged with adenosine to reveal and ablate dormant conduction. In group B, PVI was performed with the patient either in spontaneous or in induced AF. If AF did not terminate with PVI, ablation was continued by targeting extra-PV AF sources with the desired procedural end point of termination to sinus rhythm. Primary study end point was freedom from arrhythmia during 1-year follow-up. In group A, adenosine provoked dormant conduction in 31 (41%) patients with a mean of 1.6±0.8 transiently recovered PVs per patient. Termination of AF during PVI was observed in 31 (65%) patients, whereas AF persisted afterward in 17 (35%) patients. AF termination occurred in 13 (76%) patients by AF source ablation. After 1-year follow-up, significantly more group B patients were free of arrhythmia recurrences (87 versus 68%; P=0.006). During redo ablation, the rate of PV reconduction did not differ between both groups (group A: 55% versus group B: 61%; P=0.25). Elimination of extra-PV AF sources after PVI is superior to sole PV isolation with the adjunct of abolishing potential dormant conduction. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02238392. © 2015 The Authors.
The Use of Continuous Electrocardiographic Holter Monitoring in Pediatric Cardiology
Begic, Zijo; Begic, Edin; Mesihovic-Dinarevic, Senka; Masic, Izet; Pesto, Senad; Halimic, Mirza; Kadic, Almira; Dobraca, Amra
2016-01-01
Objective: To show the place and role of continuous electrocardiographic twenty-four-hour ECG monitoring in daily clinical practice of pediatric cardiologists. Methods: According to protocol, 2753 patients underwent dynamic continuous ECG Holter monitoring (data collected from the “Register of ECG Holter monitoring” of Pediatric Clinic, UCC Sarajevo in period April 2003- April 2015). Results: There were 50,5% boys and 49,5% girls, aged from birth to 19 years (1,63% - neonates and infants, 2,6% - toddlers, 9,95% - preschool children, 35,5% - gradeschoolers and 50,3% children in puberty and adolescence). In 68,1% of patients Holter was performed for the first time. Indications for conducting Holter were: arrhythmias in 42,2% cases, precordial pain in 23,5%, suspicion of pre-excitation and/or pre-excitation in 10%, crisis of consciousness in 8%, uncorrected congenital/acquired heart defects in 4,2%, operated heart defects in 3,7%, hypertension in 3,1% cases, control of the pacemaker in 1,63% and other causes in 3,5% cases. Discharge diagnosis after ECG Holter monitoring were: insignificant arrhythmias in 47,1% cases, wandering pacemaker in 21,3%, pre-excitation in 16,2%, benign ventricular premature beats in 6,3%, atrioventricular block in 3%, sinus pause in 2.2% cases and other arrhythmias in 3,5%. In mentioned period 57 cases of Wolf Parkinson White syndrome were registered, in 4,5% of patients antiarrhythmic therapy was administered. Radiofrequent ablation was performed in 23 cases. Conclusion: The development of pediatric cardiac surgery has initiated development of pediatric arrhythmology as imperative segment of pediatric cardiology. Continuous ECG Holter monitoring has become irreplaceable method in everyday diagnostics and therapy of arrhythmias in children. PMID:27708487
Liang, Jackson J; Elafros, Melissa A; Muser, Daniele; Pathak, Rajeev K; Santangeli, Pasquale; Zado, Erica S; Frankel, David S; Supple, Gregory E; Schaller, Robert D; Deo, Rajat; Garcia, Fermin C; Lin, David; Hutchinson, Mathew D; Riley, Michael P; Callans, David J; Marchlinski, Francis E; Dixit, Sanjay
2016-11-01
Transformation from persistent to paroxysmal atrial fibrillation (AF) after ablation suggests modification of the underlying substrate. We examined the nature of initial arrhythmia recurrence in patients with nonparoxysmal AF undergoing antral pulmonary vein isolation and nonpulmonary vein trigger ablation and correlated recurrence type with long-term ablation efficacy after the last procedure. Three hundred and seventeen consecutive patients with persistent (n=200) and long-standing persistent (n=117) AF undergoing first ablation were included. AF recurrence was defined as early (≤6 weeks) or late (>6 weeks after ablation) and paroxysmal (either spontaneous conversion or treated with cardioversion ≤7 days) or persistent (lasting >7 days). During median follow-up of 29.8 (interquartile range: 14.8-49.9) months, 221 patients had ≥1 recurrence. Initial recurrence was paroxysmal in 169 patients (76%) and persistent in 52 patients (24%). Patients experiencing paroxysmal (versus persistent) initial recurrence were more likely to achieve long-term freedom off antiarrhythmic drugs (hazard ratio, 2.2; 95% confidence interval, 1.5-3.2; P<0.0001), freedom on/off antiarrhythmic drugs (hazard ratio, 2.5; 95% confidence interval, 1.6-3.8; P<0.0001), and arrhythmia control (hazard ratio, 5.2; 95% confidence interval, 2.9-9.2; P<0.0001) after last ablation. In patients with persistent and long-standing persistent AF, limited ablation targeting pulmonary veins and documented nonpulmonary vein triggers improves the maintenance of sinus rhythm and reverses disease progression. Transformation to paroxysmal AF after initial ablation may be a step toward long-term freedom from recurrent arrhythmia. © 2016 American Heart Association, Inc.
Heterotaxy syndrome and associated arrhythmias in pediatric patients.
Niu, Mary C; Dickerson, Heather A; Moore, Judson A; de la Uz, Caridad; Valdés, Santiago O; Kim, Jeffrey J; Bard, David E; Morris, Shaine A; Miyake, Christina Y
2018-04-01
Heterotaxy syndrome (HS) is a rare disorder with complex anatomy involving misarrangements of the cardiac conduction system. Arrhythmias may be related to anatomic variations and contribute to morbidity. The purpose of this study was to investigate the associations between arrhythmias, anatomy, and outcomes in a large HS cohort. A single-center retrospective review of patients ≤21 years of age diagnosed with HS was performed. A total of 337 patients were included in the study. During median follow-up of 7 years (interquartile range 2-16 years), 129 patients (38%) had ≥1 clinically significant rhythm disturbance: tachyarrhythmias in 75 (22%), bradyarrhythmias in 29 (9%), and both in 25 (7%). Factors associated with tachyarrhythmia by multivariate analysis were at least moderate atrioventricular valve regurgitation (hazard ratio [HR] 1.66; 95% confidence interval [CI] 1.11-2.50), single ventricle anatomy (HR 2.30; 95% CI 1.09-4.85), and pulmonary venous obstruction (HR 2.33; 95% CI 1.45-3.76). Isomerism subtype was not associated with tachyarrhythmias. In adjusted and unadjusted analyses, bradyarrhythmias (symptomatic sinus/atrial bradycardia and high-grade or complete heart block) were associated with left atrial isomerism (LAI) compared to right atrial isomerism (HR 7.12; 95% CI 3.01-16.9). The overall transplant-free survival of the cohort was 66%. Tachyarrhythmias, but not bradyarrhythmias, were associated with mortality or need for transplant (HR 2.24; 95% CI 1.45-3.46). Clinically significant arrhythmias are common in HS. Although bradyarrhythmias are associated with LAI, tachyarrhythmia occurrence may depend more on hemodynamic and anatomic factors than isomerism subtype. Tachyarrhythmias, but not bradyarrhythmias, are associated with death or need for transplant. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Supraventricular tachycardia induced by chocolate: is chocolate too sweet for the heart?
Parasramka, Saurabh; Dufresne, Alix
2012-09-01
Conflicting studies have been published concerning the association between chocolate and cardiovascular diseases. Fewer articles have described the potential arrhythmogenic risk related to chocolate intake. We present a case of paroxysmal supraventricular tachycardia in a woman after consumption of large quantity of chocolate. A 53-year-old woman with no significant medical history presented to us with complaints of palpitations and shortness of breath after consuming large amounts of chocolate. Electrocardiogram showed supraventricular tachycardia at 165 beats per minute, which was restored to sinus rhythm after adenosine bolus injection. Electrophysiology studies showed atrioventricular nodal reentry tachycardia, which was treated with radiofrequency ablation. Chocolate contains caffeine and theobromine, which are methylxanthines and are competitive antagonists of adenosine and can have arrhythmogenic potential. Our case very well describes an episode of tachycardia precipitated by large amount of chocolate consumption in a patient with underlying substrate. There are occasional case reports describing association between chocolate, caffeine, and arrhythmias. A large Danish study, however, did not find any association between amount of daily caffeine consumption and risk of arrhythmia.
Chow, B; French, A
2014-05-01
A six-year-old female spayed mixed-breed dog was referred following a 3-week history of lameness and progressive neurological deficits in both hindlimbs, and a 1-week history of a cardiac arrhythmia. The dog was diagnosed with hypothyroidism, atrial fibrillation, myocardial dysfunction and arterial thromboembolism. Cardioversion occurred after 2 weeks of levothyroxine supplementation, with improved systolic function over time. To the authors' knowledge, this is the first case reported in the veterinary or human literature documenting hypothyroidism with persistent atrial fibrillation being converted to sinus rhythm with levothyroxine as sole therapy. © 2014 British Small Animal Veterinary Association.
Estimating time-varying RSA to examine psychophysiological linkage of marital dyads.
Gates, Kathleen M; Gatzke-Kopp, Lisa M; Sandsten, Maria; Blandon, Alysia Y
2015-08-01
One of the primary tenets of polyvagal theory dictates that parasympathetic influence on heart rate, often estimated by respiratory sinus arrhythmia (RSA), shifts rapidly in response to changing environmental demands. The current standard analytic approach of aggregating RSA estimates across time to arrive at one value fails to capture this dynamic property within individuals. By utilizing recent methodological developments that enable precise RSA estimates at smaller time intervals, we demonstrate the utility of computing time-varying RSA for assessing psychophysiological linkage (or synchrony) in husband-wife dyads using time-locked data collected in a naturalistic setting. © 2015 Society for Psychophysiological Research.
A case of atrial tachycardia treated with ivabradine as bridge to ablation.
Meles, Ester; Carbone, Claudio; Maggiolini, Stefano; Moretti, Paolo; DE Carlini, Caterina C; Gentile, Gaetano; Gnecchi-Ruscone, Tomaso
2015-05-01
Ivabradine is indicated in cardiac failure and ischemia to reduce sinus rate by inhibition of the pacemaker I(f) current in sinoatrial node. We report a case of an 18-year-old woman with left atrial tachyarrhythmia resistant to several antiarrhythmic drugs and to electric cardioversion who responded only to ivabradine, which significantly reduced heart rate without abolishing the arrhythmia itself. An ectopic focus in the ostium of left pulmonary veins was found and the patient was successfully ablated. We suggest that ivabradine might be therefore useful in the treatment of supraventricular tachyarrhythmias due to an enhanced automaticity. © 2015 Wiley Periodicals, Inc.
Minzioni, G; Graffigna, A; Pagani, F; Vigano, M
1993-12-01
To restore sinus rhythm in the remaining heart chambers of six adult patients with atrial septal defect and chronic or paroxysmal atrial fibrillation, electrical, right atrial isolation associated with surgical correction of the defect was performed. All but one patient was free from atrial fibrillation without medication 2-25 months after operation. The isolated right atrial appendages showed intrinsic rhythmical activity in five patients and no electrical activity in one. Right atrial isolation is a safe and effective procedure that abolishes atrial fibrillation in patients with arrhythmia after surgical correction of atrial septal defect.
Physiological Response to Social Evaluative Threat in Adolescents with Autism Spectrum Disorder
Edmiston, E. Kale; Jones, Robin M.
2016-01-01
The Trier Social Stress Test (TSST) was employed to study response to social evaluative threat in male adolescents with Autism Spectrum Disorder (ASD, n = 21) and typical development (n = 13). Participants wore a mobile electrocardiogram to collect heart rate data. There were significant group effects on respiratory sinus arrhythmia (RSA), a measure of parasympathetic nervous system function, with lower values in ASD (F = 4.97). Bivariate correlations also showed a significant relationship between parent reports of social problems and RSA response to the TSST (r = −0.586). These findings suggest that autonomic dysregulation may contribute to social deficits in adolescents with ASD. PMID:27318810
Stoneman, P; Gilligan, P; Mahon, P; Sheahan, R
2017-11-01
Vernakalant hydrochloride is a rapid-acting antiarrhythmic drug licensed in the EU since 2010 for the conversion of recent-onset atrial fibrillation with proven efficacy and safety when compared with placebo and amiodarone in randomized clinical trials. The aim of our study was to determine the feasibility of same day discharge (following 2 h monitoring) from the emergency department after successful cardioversion using vernakalant hydrochloride. Patients with recent-onset atrial fibrillation treated in the emergency department of a large Dublin academic teaching hospital. Patients received a maximum of two weight based 10 min infusions of vernakalant. Hypotensive events (>30% initial blood pressure), arrhythmias, conversion rates, and time to conversion were recorded. Sinus rhythm was restored in 35 out of 42 patients (83%) in an average of 8.8 min (median 8 min), average CHA2DS2-VASc of 0.92, HAS-BLED of 0.21 and average symptoms duration of 12 h. There were no hypotensive or arrhythmogenic events. 41 out of 42 patients were discharged after 2 h of monitoring. Vernakalant hydrochloride has provided a quick, safe, and practical means of achieving rapid restoration of sinus rhythm in our ED population with stable recent-onset AF who would otherwise not have undergone routine electrically cardioversion and same day discharge.
[Left versus bi-atrial radiofrequency ablation in the treatment of atrial fibrillation].
Wang, Jian-Gang; Meng, Xu; Li, Hui
2008-11-25
To evaluate the effectiveness of radiofrequency modified maze operation for the treatment of atrial fibrillation (AF) and compare the results of the left versus bi-atrial procedures. 305 patients of organic heart disease combined with AF, 117 males and 188 females, aged (53 +/- 10), that underwent cardiac valve operation (n = 293) and/or coronary artery bypass graft surgery (n = 14), received concomitant atrial fibrillation, bi-atrial (n = 160) or left atrial (n = 145) with a mean duration of (36 +/- 43) months. Follow-up was conducted for (28 +/- 5) (3 - 42) months. Thirteen patients (4.3%) died postoperatively: 7 died of multisystem and organ failure, 3 of low cardiac output, 1 of rupture of left ventricle, 1 of arrhythmia, and 1 of sudden death. During the follow-up, 1 patient died of heart failure, 1 of encephalorrhagia and 1 of unknown reason in the bi-atrial group. At the end of the procedure 223 patients (73.1%) had sinus rhythm, with a sinus rhythm rate of 66.9% (107/160) in the bi-atrial group, significant lower than that in the left atrial group (80.0%, 116/145, P < 0.05). At late follow-up, 215 of the 266 patients (80.8%) were in stable sinus rhythm. Sinus rhythm rate of the bi-atrial group was 80.0%, not significantly different from that of the left atrial group (81.9%, P > 0.05). The Kaplan-Meier survival analysis showed there was no significant difference in the AF rhythm rate between these 2 groups (P = 0.33). Logistic regression analysis showed that the left atrial diameter of >/= 80 mm was an independent predictor of AF recurrence. Both the left and bi-atrial procedures are successful in terms of restoring sinus rhythm. Left atrial ablation in severe cases and where the incision of right atrium is not needed is a reasonable choice.
Mapping of a gene for long QT syndrome to chromosome 4q25-27
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schott, J.J.; Charpentier, F.; Peltier, S.
1995-11-01
Long QT syndrome (LQTS) is a heterogeneous inherited disorder causing syncope and sudden death from ventricular arrhythmias. A first locus for this disorder was mapped to chromosome 11p15.5. However, locus heterogeneity has been demonstrated in several families, and two other loci have recently been located on chromosomes 7q35-36 and 3p21-24. We used linkage analysis to map the locus in a 65-member family in which LQTS was associated with more marked sinus bradycardia than usual, leading to sinus node dysfunction. Linkage to chromosome 11p15.5, 7q35-36, or 3p21-24 was excluded. Positive linkage was obtained for markers located on chromosome 4q25-27. A maximalmore » LOD score of 7.05 was found for marker D4S402. The identification of a fourth locus for LQTS confirms its genetic heterogeneity. Locus 4q25-27 is associated with a peculiar phenotype within the LQTS entity. 42 refs., 4 figs., 3 tabs.« less
Imaging of the coronary sinus: normal anatomy and congenital abnormalities.
Shah, Sanket S; Teague, Shawn D; Lu, Jimmy C; Dorfman, Adam L; Kazerooni, Ella A; Agarwal, Prachi P
2012-01-01
Knowledge of the anatomy of the coronary sinus (CS) and cardiac venous drainage is important because of its relevance in electrophysiologic procedures and cardiac surgeries. Several procedures make use of the CS, such as left ventricular pacing, mapping and ablation of arrhythmias, retrograde cardioplegia, targeted drug delivery, and stem cell therapy. As a result, it is more important for physicians interpreting the results of computed tomographic (CT) examinations dedicated to the heart or including the heart to be able to identify normal variants and congenital anomalies and to understand their clinical importance. Abnormalities of the CS range from anatomic morphologic variations to hemodynamically significant anomalies such as an unroofed CS, anomalous pulmonary venous connection to the CS, and coronary artery-CS fistula. It can be important to identify some anatomic variations, even though they are clinically occult, to ensure appropriate preprocedural planning. Both CT and magnetic resonance imaging provide excellent noninvasive depiction of the anatomy and anomalies of the CS. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.324105220/-/DC1.
Addressing the controversy of rate-versus-rhythm control in atrial fibrillation.
Contractor, Tahmeed; Levin, Vadim; Desai, Ravi; Marchlinski, Francis E
2013-09-01
Atrial fibrillation is the most common sustained cardiac arrhythmia and significantly increases patient risk of stroke, cardiomyopathy, and mortality. Rate versus rhythm control as the "best" treatment strategy remains an issue of considerable, ongoing debate. A multitude of clinical trials have compared the 2 strategies and have not shown any benefit of one approach over the other. However, the trials were conducted in specific subgroups of patients and demonstrated low success rates with antiarrhythmic drug (AAD) therapy and a high incidence of adverse AAD effects. Sub-analyses of the trials have confirmed that successful rhythm control with sinus rhythm restoration is associated with a significant reduction in patient mortality. More recently, radiofrequency ablation (RFA) has emerged as a relatively effective procedure for maintaining sinus rhythm compared with use of AADs. Prospective randomized studies have shown good treatment results after the use of RFA, with acceptable risk. Given the limitation of pharmacologic rate versus rhythm control studies, and the promise of RFA, rhythm control should again be reconsidered as the "best" approach for managing many subgroups of patients with atrial fibrillation.
A KCNQ1 mutation causes age-dependant bradycardia and persistent atrial fibrillation.
Ki, Chang-Seok; Jung, Chae Lim; Kim, Hyun-ji; Baek, Kwan-Hyuck; Park, Seung Jung; On, Young Keun; Kim, Ki-Suk; Noh, Su Jin; Youm, Jae Boum; Kim, June Soo; Cho, Hana
2014-03-01
Atrial fibrillation (AF) is the most common arrhythmia. Gain-of-function mutations in KCNQ1, the pore-forming α-subunit of the slow delayed rectifier K current (IKs) channel, have been associated with AF. The purpose of this study was functional assessment of a mutation in KCNQ1 identified in a family with persistent AF and sinus bradycardia. We investigated whether this KCNQ1 missense mutation could form the genetic basis for AF and bradycardia simultaneously in this family. Sanger sequencing in a family with hereditary persistent AF identified a novel KCNQ1 variant (V241F) in a highly conserved region of S4 domain. The proband and her son developed bradycardia and persistent AF in an age-dependent fashion. The other son was a mutation carrier but he showed sinus bradycardia and not AF. Whole-cell patch clamp electrophysiology showed that V241F mutation in KCNQ1 shifted the activation curve to the left and dramatically slowed deactivation, leading to a constitutively open-like phenotype. Computer modeling showed that V241F would slow pacemaker activity. Also, simulations of atrial excitation predicted that V241F results in extreme shortening of action potential duration, possibly resulting in AF. Our study indicates that V241F might cause sinus bradycardia by increasing IKs. Additionally, V241F likely shortens atrial refractoriness to promote a substrate for reentry. KCNQ1 mutations have previously been described in AF, yet this is the first time a mutation in KCNQ1 is associated with age-dependent bradycardia and persistent AF. This finding further supports the hypothesis that sinus node dysfunction contributes to the development of AF.
Fast T Wave Detection Calibrated by Clinical Knowledge with Annotation of P and T Waves.
Elgendi, Mohamed; Eskofier, Bjoern; Abbott, Derek
2015-07-21
There are limited studies on the automatic detection of T waves in arrhythmic electrocardiogram (ECG) signals. This is perhaps because there is no available arrhythmia dataset with annotated T waves. There is a growing need to develop numerically-efficient algorithms that can accommodate the new trend of battery-driven ECG devices. Moreover, there is also a need to analyze long-term recorded signals in a reliable and time-efficient manner, therefore improving the diagnostic ability of mobile devices and point-of-care technologies. Here, the T wave annotation of the well-known MIT-BIH arrhythmia database is discussed and provided. Moreover, a simple fast method for detecting T waves is introduced. A typical T wave detection method has been reduced to a basic approach consisting of two moving averages and dynamic thresholds. The dynamic thresholds were calibrated using four clinically known types of sinus node response to atrial premature depolarization (compensation, reset, interpolation, and reentry). The determination of T wave peaks is performed and the proposed algorithm is evaluated on two well-known databases, the QT and MIT-BIH Arrhythmia databases. The detector obtained a sensitivity of 97.14% and a positive predictivity of 99.29% over the first lead of the validation databases (total of 221,186 beats). We present a simple yet very reliable T wave detection algorithm that can be potentially implemented on mobile battery-driven devices. In contrast to complex methods, it can be easily implemented in a digital filter design.
Optogenetic control of the cardiac conduction system (Conference Presentation)
NASA Astrophysics Data System (ADS)
Crocini, Claudia; Ferrantini, Cecilia; Coppini, Raffaele; Loew, Leslie M.; Cerbai, Elisabetta; Poggesi, Corrado; Pavone, Francesco S.; Sacconi, Leonardo
2016-03-01
Fatal cardiac arrhythmias are a major medical and social issue in Western countries. Current implantable pacemaker/defibrillators have limited effectiveness and are plagued by frequent malfunctions and complications. Here, we aim at setting up a new method to map and control the electrical activity of whole isolated mouse hearts. We employ a transgenic mouse model expressing Channel Rhodopsin-2 (ChR2) in the heart coupled with voltage optical mapping to monitor and control action potential propagation. The whole heart is loaded with the fluorinated red-shifted voltage sensitive dye (di-4-ANBDQPQ) and imaged with the central portion (128 x 128 pixel) of sCMOS camera operating at frame rate of 1.6 kHz. The wide-field imaging system is implemented with a random access ChR2 activation developed using two orthogonally-mounted acousto-optical deflectors (AODs). AODs rapidly scan different sites of the sample with a commutation time of 4 μs, allowing us to design ad hoc ChR2-stimulation pattern. First, we demonstrate the capability of our system in manipulating the conduction system of the whole mouse heart by changing the electrical propagation features. Then, we explore the efficacy of the random access ChR2 stimulation in inducing arrhythmias as well as to restore the cardiac sinus rhythm during an arrhythmic event. This work shows the potentiality of this new method for studying the mechanisms of arrhythmias and reentry in healthy and diseased hearts, as well as the basis of intra-ventricular dyssynchrony.
Li, Song-Nan; Wang, Lu; Dong, Jian-Zeng; Yu, Rong-Hui; Long, De-Yong; Tang, Ri-Bo; Sang, Cai-Hua; Jiang, Chen-Xi; Liu, Nian; Bai, Rong; Du, Xin; Ma, Chang-Sheng
2018-06-01
Left ventricular hypertrophy (LVH) is an independent predictor of new-onset atrial fibrillation. Whether LVH can predict the recurrence of arrhythmia after radiofrequency catheter ablation (RFCA) in patients with paroxysmal atrial fibrillation (PAF) remains unclear. PAF patients with baseline-electrocardiographic LVH has a higher recurrence rate after RFCA procedure compared with those without LVH. A total of 436 patients with PAF undergoing first RFCA were consecutively enrolled and clustered into 2 groups based on electrocardiogram (ECG) findings: non-ECG LVH (218 patients) and ECG LVH (218 patients). LVH was characterized by the Romhilt-Estes point score system; the score ≥5points were defined as LVH. At 42 months' (interquartile range, 18.0-60.0 months) follow-up after RFCA, 151 (69.3%) patients in the non-ECG LVH group and 108 (49.5%) patients in the ECG LVH group maintained sinus rhythm without using antiarrhythmic drugs (P < 0.001). Patients with ECG LVH tended to experience a much higher prevalence of stroke and recurrence of atrial arrhythmia episodes compared with those without ECG LVH (log-rank P < 0.001). Multivariate analysis found the presence of ECG LVH and left atrial diameter to be independent risk factors for recurrence after adjusting for confounding factors. The presence of ECG LVH was a strong and independent predictor of recurrence in patients with PAF following RFCA. © 2018 Wiley Periodicals, Inc.
Makowski, Marcin; Smorag, Ireneusz; Makowska, Joanna; Bissinger, Andrzej; Grycewicz, Tomasz; Paśnik, Jarek; Kidawa, Michal; Lubiński, Andrzej; Zielińska, Marzenna; Baj, Zbigniew
2017-05-15
Atrial fibrillation (AF) is associated with increased risk of thromboembolic complications. One of the markers of the increased risk of hypercoagulable state is platelet hyperreactivity. The aim of the study was to assess impact of arrhythmia on platelet reactivity. The study included 36 (mean age 48,3; range 21-60) male patients with lone atrial fibrillation, with exclusion of concomitant diseases known to trigger hypercoagulable state. The AF patients underwent cardioversion to restore sinus rhythm and were subsequently under observation for 1month. Echocardiography, ECG and blood collection was performed before cardioversion (T0) and 4weeks after successful cardioversion (T1). During the study period patients have been contacted and examined every week and 24h ECG monitoring was performed. Platelet reactivity was assessed based on changes of CD62 and CD42b expression on platelet surface after stimulation with thrombin. Also changes in MPV were assessed. In all patients sinus rhythm was maintained at the end of the study period, however in 14 patients recurrences of AF were observed, confirmed by 24h ECG monitoring (atrial fibrillation recurrence group - AFR) and 22 patients maintained sinus rhythm throughout the whole study period (SR group). Mean fluorescence intensity (MFI) of CD62 on thrombin stimulated platelets decreased significantly 4weeks after electrical cardioversion as compared to T0 (48.04±22.42 vs 41.47±16.03; p<0.01). Also MFI of CD42b on thrombin stimulated platelets decreased significantly 4weeks after electrical cardioversion as compared to T0 (22.16±10.82 vs 12.06±5.99; p<0.0001). Platelets reactivity estimated by CD 62 expression in SR group decreased significantly after 4weeks observation (58.01±15.26 vs 46.57±13.44; p<0.001) opposite to AFR group 35.66±21.87 vs 34.54±16.4; p-ns). Moreover there were significant differences between basal reactivity during AF between SR and AFR groups (58.01±15.26 vs 35.66±21.87; p-0.01). MFI of CD42b on thrombin stimulated platelets decreased significantly both in AFR and SR groups (22.05±11.36 vs 13.8±6.03; p<0.001 and 21.87±14.18 vs 10.04±5.09; p<0005). MPV decreased significantly 4weeks after electrical cardioversion as compared to T0 (8.81±0.19 vs 8.42±0.14; p<0.0001). The changes of platelet reactivity to thrombin observed after restoration of sinus rhythm in patients prove that arrhythmia intrinsically leads to increased reactivity of platelets. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Physiological Response to Social Evaluative Threat in Adolescents with Autism Spectrum Disorder.
Edmiston, E Kale; Jones, Robin M; Corbett, Blythe A
2016-09-01
The Trier Social Stress Test (TSST) was employed to study response to social evaluative threat in male adolescents with Autism Spectrum Disorder (ASD, n = 21) and typical development (n = 13). Participants wore a mobile electrocardiogram to collect heart rate data. There were significant group effects on respiratory sinus arrhythmia (RSA), a measure of parasympathetic nervous system function, with lower values in ASD (F = 4.97). Bivariate correlations also showed a significant relationship between parent reports of social problems and RSA response to the TSST (r = -0.586). These findings suggest that autonomic dysregulation may contribute to social deficits in adolescents with ASD.
The Popeye domain containing genes: essential elements in heart rate control
Schindler, Roland F.; Poon, Kar Lai; Simrick, Subreena
2012-01-01
The Popeye domain containing (Popdc) gene family displays preferential expression in skeletal muscle and heart. Only recently a significant gain in the understanding of the function of Popdc genes in the heart has been obtained. The Popdc genes encode membrane proteins harboring an evolutionary conserved Popeye domain, which functions as a binding domain for cyclic adenosine monophosphate (cAMP). Popdc proteins interact with the two-pore channel TREK-1 and enhance its current. This protein interaction is modulated by cAMP. Null mutations of members of the Popdc gene family in zebrafish and mouse are associated with severe cardiac arrhythmia phenotypes. While in zebrafish an atrioventricular block was prevalent, in mouse a stress-induced sinus bradycardia was observed, which was due to the presence of sinus pauses. Moreover, the phenotype develops in an age-dependent manner, being absent in the young animal and becoming increasingly severe, as the animals grow older. This phenotype is reminiscent of the sick sinus syndrome (SSS), which affects mostly the elderly and is characterized by the poor ability of the cardiac pacemaker to adapt the heart rate to the physiological demand. While being a prevalent disease, which is responsible for a large fraction of pacemaker implantations in Western countries, SSS is poorly understood at the molecular level. It is therefore expected that the study of the molecular basis of the stress-induced bradycardia in Popdc mice will shed new light on the etiology of pacemaker disease. PMID:24282731
The Popeye domain containing genes: essential elements in heart rate control.
Schindler, Roland F; Poon, Kar Lai; Simrick, Subreena; Brand, Thomas
2012-12-01
The Popeye domain containing (Popdc) gene family displays preferential expression in skeletal muscle and heart. Only recently a significant gain in the understanding of the function of Popdc genes in the heart has been obtained. The Popdc genes encode membrane proteins harboring an evolutionary conserved Popeye domain, which functions as a binding domain for cyclic adenosine monophosphate (cAMP). Popdc proteins interact with the two-pore channel TREK-1 and enhance its current. This protein interaction is modulated by cAMP. Null mutations of members of the Popdc gene family in zebrafish and mouse are associated with severe cardiac arrhythmia phenotypes. While in zebrafish an atrioventricular block was prevalent, in mouse a stress-induced sinus bradycardia was observed, which was due to the presence of sinus pauses. Moreover, the phenotype develops in an age-dependent manner, being absent in the young animal and becoming increasingly severe, as the animals grow older. This phenotype is reminiscent of the sick sinus syndrome (SSS), which affects mostly the elderly and is characterized by the poor ability of the cardiac pacemaker to adapt the heart rate to the physiological demand. While being a prevalent disease, which is responsible for a large fraction of pacemaker implantations in Western countries, SSS is poorly understood at the molecular level. It is therefore expected that the study of the molecular basis of the stress-induced bradycardia in Popdc mice will shed new light on the etiology of pacemaker disease.
[Symptomatic sinus dysfunction. A new use of electrophysiology].
Graux, P; Jacquemart, T; Carlioz, R; Lemaire, N; Dutoit, A; Croccel, L
1993-06-01
The authors undertook a prospective electrophysiological study of 950 patients: 53 subjects considered to be "controls" since they were free of any history of syncope or faintness were identified, as well as 39 symptomatic subjects with a strong suspicion of sinus dysfunction, since no other detectable cause of fainting episodes was found by extracardiac investigation, 24 hour ECG nor electrophysiology. Following the creation of a computerised tool enabling not only the entry of indirect tests, processing, averaging of results, printing and memorization, but also assistance in interpretation, several electrophysiological parameters were used: heart rate and existence of sinus arrhythmia, Strauss tests with adjusted data or not, effective nodal refractory period, Guize, Narula and Mandel tests, and an atropine (0.03 mg/kg) test which was performed only in the symptomatic group. These tests were studied by single-variate and correlative analysis to define their normal ranges, their critical values and their dependence or independence. The performance of each test (i.e. its efficiency, and the specificity and sensitivity of each critical value) was measured. Tests found to be most useful (specificity and efficiency > 90%) were as follows: Mandel test = CSRT > or = 534 ms, Narula test = TECASA > or = 339 ms, heart rate < or = 55/min, type II, IIa and chaotic Strauss curve associated with a pathological Guize test. The combination of these tests in this algorithm resulted in an increase in sensitivity to 84%, at the price of a very moderate fall in specificity to 87%.(ABSTRACT TRUNCATED AT 250 WORDS)
Viganò, M; Graffigna, A; Pagani, F; Salerno, J A
1991-12-01
Surgery can provide treatment for supraventricular tachyarrhythmias without operative risk and with a definite improvement of patients' quality of life. Ectopic atrial tachycardia is a rare but invalidating arrhythmia that may lead to cardiomyopathy: intraoperative mapping is necessary for the location of the location of the ectopic focus; in our experience, surgical, cryothermal or isolation ablation of the area were effective in 9 patients out of 9, with regression of the cardiomyopathy. Atrioventricular node reentry tachycardia is a reentry tachycardia which is often associated with Wolff-Parkinson-White syndrome and is amenable to surgical treatment. Discrete cryolesions around the Koch triangle are effective in interrupting the atrial inputs to the atrioventricular node and therefore the reentry mechanism: in our experience, 7 patients were successfully treated without operative mortality: 3 patients underwent surgical ablation of Kent bundles as well. Atrial fibrillation is not based on a well-defined mechanism, and therefore does not permit an electrically-guided surgical treatment. However, in case of atrial septal defect it is possible to isolate the enlarged right atrium in order to allow sinus rhythm to activate the left atrium and ventricles.(ABSTRACT TRUNCATED AT 250 WORDS)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Branch, C.A.; Goldberg, D.A.; Ewing, J.R.
1994-12-31
The gaseous fluorocarbon trifluoromethane has recently been investigated for its potential as an in vivo gaseous indicator for nuclear magnetic resonance studies of brain perfusion. Trifluoromethane may also have significant value as a replacement for chlorofluorocarbon fire retardants. Because of possible species-specific cardiotoxic and anesthetic properties, the toxicological evaluation of trifluoromethane in primates (Papio anubis) is necessary prior to its evaluation in humans. We report the acute cardiac and central nervous system effects of trifluoromethane in eight anesthetized baboons. A dose-response effect was established for respiratory rate, electroencephalogram, and cardiac sinus rate, which exhibited a stepwise decrease from 10% trifluoromethane.more » No spontaneous arrhythmias were noted, and arterial blood pressure remained unchanged at any inspired level. Intravenous epinephrine infusions (1 {mu}g/kg) induced transient cardiac arrhythmia in 1 animal only at 70% FC-23 (v/v) trifluoromethane. Trifluoromethane appears to induce mild dose-related physiological changes at inspired levels of 30% or more, indicative of an anesthetic effect. These data suggest that trifluoromethane may be safe to use in humans, without significant adverse acute effects, at an inspired level of 30%. 23 refs., 3 figs., 3 tabs.« less
Chen, Shou-Qiang; Xing, Shan-Shan; Gao, Hai-Qing
2014-01-01
Objective: In addition to ambulatory Holter electrocardiographic recording and transtelephonic electrocardiographic monitoring (TTM), a cardiac remote monitoring system can provide an automatic warning function through the general packet radio service (GPRS) network, enabling earlier diagnosis, treatment and improved outcome of cardiac diseases. The purpose of this study was to estimate its clinical significance in preventing acute cardiac episodes. Methods: Using 2 leads (V1 and V5 leads) and the automatic warning mode, 7160 patients were tested with a cardiac remote monitoring system from October 2004 to September 2007. If malignant arrhythmias or obvious ST-T changes appeared in the electrocardiogram records was automatically transferred to the monitoring center, the patient and his family members were informed, and the corresponding precautionary or therapeutic measures were implemented immediately. Results: In our study, 274 cases of malignant arrhythmia, including sinus standstill and ventricular tachycardia, and 43 cases of obvious ST-segment elevation were detected and treated. Because of early detection, there was no death or deformity. Conclusions: A cardiac remote monitoring system providing an automatic warning function can play an important role in preventing acute cardiac episodes. PMID:25674124
Successful electrical cardioversion of supraventricular tachycardia in a pregnant patient
Yılmaz, Fevzi; Beydilli, Inan; Kavalcı, Cemil; Yılmaz, Serkan
2012-01-01
Summary Background: Pregnancy can precipitate cardiac arrhythmias not previously present in seemingly well individuals. Atrial and ventricular premature beats are frequently present during pregnancy and are usually benign. Supraventricular tachycardia and malignant ventricular tachyarrhythmias occur less frequently. Maternal and fetal arrhythmias occurring during pregnancy may jeopardize the life of the mother and the fetus. Case Report: A 32-year-old pregnant women at 26 weeks gestation presented to the emergency department with palpitation. She had mild chest discomfort after a supraventricular tachycardia (SVT) episode but did not have syncope. After monitoring and access of an IV line, vagal manoeuvres were applied but the rhythm was resistant. Then she was treated with 5 mg metoprolol IV, but the SVT persisted. Then after IV infusion of adenosine triphosphate 6 to 12 mg, the rhythm was resistant. Synchronized cardioversion with 100 joules was performed. Patients’ rhythm was normalized to a sinus rhythm. She was discharged from hospital without any adverse effects following 24-hour monitoring. Conclusions: All pregnant patients with SVT require careful maternal and fetal monitoring during treatment, and close collaboration between the managing obstetrician and the cardiologist is essential. PMID:23569481
NASA Astrophysics Data System (ADS)
Vagos, Márcia R.; Arevalo, Hermenegild; de Oliveira, Bernardo Lino; Sundnes, Joakim; Maleckar, Mary M.
2017-09-01
Models of cardiac cell electrophysiology are complex non-linear systems which can be used to gain insight into mechanisms of cardiac dynamics in both healthy and pathological conditions. However, the complexity of cardiac models can make mechanistic insight difficult. Moreover, these are typically fitted to averaged experimental data which do not incorporate the variability in observations. Recently, building populations of models to incorporate inter- and intra-subject variability in simulations has been combined with sensitivity analysis (SA) to uncover novel ionic mechanisms and potentially clarify arrhythmogenic behaviors. We used the Koivumäki human atrial cell model to create two populations, representing normal Sinus Rhythm (nSR) and chronic Atrial Fibrillation (cAF), by varying 22 key model parameters. In each population, 14 biomarkers related to the action potential and dynamic restitution were extracted. Populations were calibrated based on distributions of biomarkers to obtain reasonable physiological behavior, and subjected to SA to quantify correlations between model parameters and pro-arrhythmia markers. The two populations showed distinct behaviors under steady state and dynamic pacing. The nSR population revealed greater variability, and more unstable dynamic restitution, as compared to the cAF population, suggesting that simulated cAF remodeling rendered cells more stable to parameter variation and rate adaptation. SA revealed that the biomarkers depended mainly on five ionic currents, with noted differences in sensitivities to these between nSR and cAF. Also, parameters could be selected to produce a model variant with no alternans and unaltered action potential morphology, highlighting that unstable dynamical behavior may be driven by specific cell parameter settings. These results ultimately suggest that arrhythmia maintenance in cAF may not be due to instability in cell membrane excitability, but rather due to tissue-level effects which promote initiation and maintenance of reentrant arrhythmia.
Locati, E T; Moya, A; Oliveira, M; Tanner, H; Willems, R; Lunati, M; Brignole, M
2016-08-01
SYNARR-Flash study (Monitoring of SYNcopes and/or sustained palpitations of suspected ARRhythmic origin) is an international, multicentre, observational, prospective trial designed to evaluate the role of external 4-week electrocardiogram (ECG) monitoring in clinical work-up of unexplained syncope and/or sustained palpitations of suspected arrhythmic origin. Consecutive patients were enrolled within 1 month after unexplained syncope or palpitations (index event) after being discharged from emergency room or hospitalization without a conclusive diagnosis. A 4-week ECG monitoring was obtained by external high-capacity loop recorder (SpiderFlash-T(®), Sorin) storing patient-activated and auto-triggered tracings. Diagnostic monitorings included (i) conclusive events with reoccurrence of syncope or palpitation with concomitant ECG recording (with/without arrhythmias) and (ii) events with asymptomatic predefined significant arrhythmias (sustained supraventricular or ventricular tachycardia, advanced atrio-ventricular block, sinus bradycardia <30 b.p.m., pauses >6 s). SYNARR-Flash study enrolled 395 patients (57.7% females, 56.9 ± 18.7 years, 28.1% with syncope, and 71.9% with palpitations) from 10 European centres. For syncope, the 4-week diagnostic yield was 24.5%, and predictors of diagnostic events were early start of recording (0-15 vs. >15 days after index event) (OR 6.2, 95% CI 1.3-29.6, P = 0.021) and previous history of supraventricular arrhythmias (OR 3.6, 95% CI 1.4-9.7, P = 0.018). For palpitations, the 4-week diagnostic yield was 71.6% and predictors of diagnostic events were history of recurrent palpitations (P < 0.001) and early start of recording (P = 0.001). The 4-week external ECG monitoring can be considered as first-line tool in the diagnostic work-up of syncope and palpitation. Early recorder use, history of supraventricular arrhythmia, and frequent previous events increased the likelihood of diagnostic events during the 4-week external ECG monitoring. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Cardiology.
Gravity and Development of Cardiopulmonary Reflex
NASA Astrophysics Data System (ADS)
Nagaoka, Shunji; Eno, Yuko; Ohira, Yoshinobu
Cardio-pulmonary reflex, which our cardiac activity is synchronized to the respiration by autonomic nervous system regulation, is called as "respiratory sinus arrhythmia" and commonly found in adult. The physiological function of the espiratory sinus arrhythmia is considered to maximize the gas exchange during respiration cycle. This respiration induced heart rate variability (RHRV) is only found in mammals and avian showing a remarkable postnatal development, whereas no RHRV in aquatic species such as fish or amphibian. To elucidate our hypothesis that gravity exposure may plays a key role in the postnatal development of RHRV as well as its evolutional origin in these ground animals, we have studied effects of hypergravity (2G) on the postnatal development of RHRV using rat. Pregnant Wister rats were kept in centrifugal cages system for 38 days from 6th days of pregnant mother to have neonates until 23 days old. Electrocardiograph was recorded from the neonates in 2 to 23 days old in 2G group with simultaneous control (1G) group. The RHRV analysis was performed by calculating a component of Fourier power spectral coincide with the respiration frequency. In both groups, averaged resting heart rate gradually increase from 2 to 23 days old. When comparing the heart rate between the two groups, the 2G group indicated significantly lower (240± 8 bpm) than 1G control (326±21 bpm, p¡0.001) in 2 days old, where as no significance in 23 days old. The RHRV of 2 days old neonates in both groups indicated very small magnitude but significantly lower in 2G group than 1G control (p¡0.01). The RHRV gradually increase during the first 2 weeks and then rapid increased to reached 45 fold of magnitude in 1G control, whereas 69 fold in 2G group. The results strongly suggested that the postnatal innervation from respiration to cardiovascular centers was gravity dependent.
Corrado, G; Santarone, M; Beretta, S; Tadeo, G; Tagliagambe, L M; Foglia-Manzillo, G; Spata, M; Miglierina, E; Acquati, F; Santarone, M
2000-04-01
To analyse the safety and impact on maintenance of sinus rhythm of transoesophageal echocardiographically guided early cardioversion associated with short-term anticoagulation in a large series of patients with atrial fibrillation and atrial flutter. Patients who were candidates for cardioversion were eligible for inclusion if they had atrial fibrillation or atrial flutter lasting longer than 2 days or of unknown duration. Patients received short-term anticoagulation with warfarin or heparin and underwent transthoracic echocardiography followed by transoesophageal echocardiography. Early cardioversion was performed if no thrombus was seen on the transoesophageal study. Warfarin was maintained for 1 month after cardioversion. In patients with atrial thrombi, cardioversion was deferred and prolonged anticoagulation was prescribed. The study population included 183 patients. One hundred and sixty nine patients without atrial thrombi underwent early cardioversion. Fourteen patients with atrial thrombi (7.6%) underwent a second transoesophageal echocardiogram after a median of 4 weeks of oral warfarin, and cardioversion was performed if clot regression was documented. No patient in our study population had a clinical thromboembolic event at 1 month follow-up (95% C.I. 0-0.016). The immediate success rate of cardioversion was better among patients with atrial fibrillation < 4 weeks duration compared with patients with atrial fibrillation of longer or of unknown duration: 96.6% vs 85%, respectively (P = 0.014). At 1 month follow-up, the percentage of arrhythmia relapses in patients with initially successful cardioversion was similar in the two groups (29% vs 26%, P = ns); thus the initial better outcome in patients with recent-onset arrhythmia was not lost. Transoesophageal echocardiography-guided early cardioversion in concert with short-term anticoagulation is safe. This approach permits abbreviation of the overall duration of atrial fibrillation and has a better impact on the maintenance of sinus rhythm for patients in whom the duration of atrial fibrillation is < 4 weeks.
Blain, G; Meste, O; Bouchard, T; Bermon, S
2005-07-01
To test whether ventilatory thresholds, measured during an exercise test, could be assessed using time varying analysis of respiratory sinus arrhythmia frequency (f(RSA)). Fourteen sedentary subjects and 12 endurance athletes performed a graded and maximal exercise test on a cycle ergometer: initial load 75 W (sedentary subjects) and 150 W (athletes), increments 37.5 W/2 min. f(RSA) was extracted from heart period series using an evolutive model. First (T(V1)) and second (T(V2)) ventilatory thresholds were determined from the time course curves of ventilation and ventilatory equivalents for O(2) and CO(2). f(RSA) was accurately extracted from all recordings and positively correlated to respiratory frequency (r = 0.96 (0.03), p<0.01). In 21 of the 26 subjects, two successive non-linear increases were determined in f(RSA), defining the first (T(RSA1)) and second (T(RSA2)) f(RSA) thresholds. When expressed as a function of power, T(RSA1) and T(RSA2) were not significantly different from and closely linked to T(V1) (r = 0.99, p<0.001) and T(V2) (r = 0.99, p<0.001), respectively. In the five remaining subjects, only one non-linear increase was observed close to T(V2). Significant differences (p<0.04) were found between athlete and sedentary groups when T(RSA1) and T(RSA2) were expressed in terms of absolute and relative power and percentage of maximal aerobic power. In the sedentary group, T(RSA1) and T(RSA2) were 150.3 (18.7) W and 198.3 (28.8) W, respectively, whereas in the athlete group T(RSA1) and T(RSA2) were 247.3 (32.8) W and 316.0 (28.8) W, respectively. Dynamic analysis of f(RSA) provides a useful tool for identifying ventilatory thresholds during graded and maximal exercise test in sedentary subjects and athletes.
Blain, G; Meste, O; Bouchard, T; Bermon, S; Segura, R.
2005-01-01
Objective: To test whether ventilatory thresholds, measured during an exercise test, could be assessed using time varying analysis of respiratory sinus arrhythmia frequency (fRSA). Methods: Fourteen sedentary subjects and 12 endurance athletes performed a graded and maximal exercise test on a cycle ergometer: initial load 75 W (sedentary subjects) and 150 W (athletes), increments 37.5 W/2 min. fRSA was extracted from heart period series using an evolutive model. First (TV1) and second (TV2) ventilatory thresholds were determined from the time course curves of ventilation and ventilatory equivalents for O2 and CO2. Results: fRSA was accurately extracted from all recordings and positively correlated to respiratory frequency (r = 0.96 (0.03), p<0.01). In 21 of the 26 subjects, two successive non-linear increases were determined in fRSA, defining the first (TRSA1) and second (TRSA2) fRSA thresholds. When expressed as a function of power, TRSA1 and TRSA2 were not significantly different from and closely linked to TV1 (r = 0.99, p<0.001) and TV2 (r = 0.99, p<0.001), respectively. In the five remaining subjects, only one non-linear increase was observed close to TV2. Significant differences (p<0.04) were found between athlete and sedentary groups when TRSA1 and TRSA2 were expressed in terms of absolute and relative power and percentage of maximal aerobic power. In the sedentary group, TRSA1 and TRSA2 were 150.3 (18.7) W and 198.3 (28.8) W, respectively, whereas in the athlete group TRSA1 and TRSA2 were 247.3 (32.8) W and 316.0 (28.8) W, respectively. Conclusions: Dynamic analysis of fRSA provides a useful tool for identifying ventilatory thresholds during graded and maximal exercise test in sedentary subjects and athletes. PMID:15976169
Fast T Wave Detection Calibrated by Clinical Knowledge with Annotation of P and T Waves
Elgendi, Mohamed; Eskofier, Bjoern; Abbott, Derek
2015-01-01
Background There are limited studies on the automatic detection of T waves in arrhythmic electrocardiogram (ECG) signals. This is perhaps because there is no available arrhythmia dataset with annotated T waves. There is a growing need to develop numerically-efficient algorithms that can accommodate the new trend of battery-driven ECG devices. Moreover, there is also a need to analyze long-term recorded signals in a reliable and time-efficient manner, therefore improving the diagnostic ability of mobile devices and point-of-care technologies. Methods Here, the T wave annotation of the well-known MIT-BIH arrhythmia database is discussed and provided. Moreover, a simple fast method for detecting T waves is introduced. A typical T wave detection method has been reduced to a basic approach consisting of two moving averages and dynamic thresholds. The dynamic thresholds were calibrated using four clinically known types of sinus node response to atrial premature depolarization (compensation, reset, interpolation, and reentry). Results The determination of T wave peaks is performed and the proposed algorithm is evaluated on two well-known databases, the QT and MIT-BIH Arrhythmia databases. The detector obtained a sensitivity of 97.14% and a positive predictivity of 99.29% over the first lead of the validation databases (total of 221,186 beats). Conclusions We present a simple yet very reliable T wave detection algorithm that can be potentially implemented on mobile battery-driven devices. In contrast to complex methods, it can be easily implemented in a digital filter design. PMID:26197321
Haapaniemi, Susan; Franklin, Barry A; Wegner, James H; Hamar, Shelby; Gordon, Seymour; Timmis, Gerald C; O'Neill, William W
2007-07-15
To evaluate the cardiac demands of hunting deer, continuous ambulatory electrocardiograms were obtained in men with and without coronary artery disease (CAD) and compared with their responses to maximal treadmill testing. A volunteer sample of 25 middle-aged men (mean +/- SD 55 +/- 7 years of age), 17 of whom had known CAD, completed the study. Peak heart rate (HR) during 7 different deer hunting activities was expressed as the mean percentage of the maximal HR (HRmax) attained during treadmill testing. Periods of sustained sinus tachycardia were identified. Arrhythmias and ST-segment depression during deer hunting that were not apparent during treadmill testing were documented. Overall, 22 of 25 subjects demonstrated HR responses >85% HRmax for 1 to 65 minutes. Ten subjects exceeded the HRmax achieved during treadmill testing for 1 to 5 minutes. The relative HR response during ambulatory activity in the field was inversely related to cardiorespiratory fitness, expressed as METs (r = -0.59; p = 0.0020). Three subjects had ischemic electrocardiograms during deer hunting, but not during treadmill testing. Complex arrhythmias in the field not detected by treadmill testing included ventricular bi-trigeminy, ventricular couplets, and 8 runs of ventricular tachycardia (3 to 28 beats) in 3 subjects with documented CAD. In conclusion, deer hunting can evoke sustained HRs, ischemic ST-segment depression, and threatening ventricular arrhythmias in excess of those documented during maximal treadmill testing. The strenuous nature of deer hunting coupled with presumed hyperadrenergia and superimposed environmental stresses may contribute to the excessive cardiac demands associated with this activity.
The normal electrocardiogram of four species of conscious raptors.
Talavera, J; Guzmán, M J; del Palacio, M J Fernández; Albert, A P; Bayón, A
2008-02-01
The aim of this study was to describe normal ECG patterns and values in four species of conscious raptors (Eurasian kestrel, Griffon vulture, Little owl, and Eurasian Eagle owl). Electrocardiograms were carried out in 75 conscious birds belonging to four species of raptors. Lead II waveforms were analysed to determine amplitudes and durations of waves and intervals. Morphologic patterns of P-QRS-T deflections were analysed in the six limb leads. Rhythm, heart rate, mean electrical axis, presence of Ta wave, ST slurring, and P-on-T phenomenon were also studied. The influence of species, body weight and heart rate in electrocardiographic variables were statistically analysed (P < 0.05). Sinus rhythm was present in all tracings, showing sinus arrhythmia in four cases. Ta wave was present in six tracings and P-on-T phenomenon in four. ST segment could be identified in all tracings, being mainly high above baseline. Significant differences between species were found for all the electrocardiographic parameters. The heart rate and body weight were also found to be a significant influence in most parameters. This study provides electrocardiographic data for four species of raptors that can be used to establish comparisons for clinical purposes.
Lewis, Gregory F.; Furman, Senta A.; McCool, Martha F.; Porges, Stephen W.
2011-01-01
Three frequently used RSA metrics are investigated to document violations of assumptions for parametric analyses, moderation by respiration, influences of nonstationarity, and sensitivity to vagal blockade. Although all metrics are highly correlated, new findings illustrate that the metrics are noticeably different on the above dimensions. Only one method conforms to the assumptions for parametric analyses, is not moderated by respiration, is not influenced by nonstationarity, and reliably generates stronger effect sizes. Moreover, this method is also the most sensitive to vagal blockade. Specific features of this method may provide insights into improving the statistical characteristics of other commonly used RSA metrics. These data provide the evidence to question, based on statistical grounds, published reports using particular metrics of RSA. PMID:22138367
Cardiorespiratory coupling in health and disease.
Garcia, Alfredo J; Koschnitzky, Jenna E; Dashevskiy, Tatiana; Ramirez, Jan-Marino
2013-04-01
Cardiac and respiratory activities are intricately linked both functionally as well as anatomically through highly overlapping brainstem networks controlling these autonomic physiologies that are essential for survival. Cardiorespiratory coupling (CRC) has many potential benefits creating synergies that promote healthy physiology. However, when such coupling deteriorates autonomic dysautonomia may ensue. Unfortunately there is still an incomplete mechanistic understanding of both normal and pathophysiological interactions that respectively give rise to CRC and cardiorespiratory dysautonomia. Moreover, there is also a need for better quantitative methods to assess CRC. This review addresses the current understanding of CRC by discussing: (1) the neurobiological basis of respiratory sinus arrhythmia (RSA); (2) various disease states involving cardiorespiratory dysautonomia; and (3) methodologies measuring heart rate variability and RSA. Copyright © 2013 Elsevier B.V. All rights reserved.
Cardiorespiratory Coupling in Health and Disease
Garcia, Alfredo J.; Koschnitzky, Jenna E.; Dashevskiy, Tatiana; Ramirez, Jan-Marino
2013-01-01
Cardiac and respiratory activities are intricately linked both functionally as well as anatomically through highly overlapping brainstem networks controlling these autonomic physiologies that are essential for survival. Cardiorespiratory coupling (CRC) has many potential benefits creating synergies that promote healthy physiology. However, when such coupling deteriorates autonomic dysautonomia may ensue. Unfortunately there is still an incomplete mechanistic understanding of both normal and pathophysiological interactions that respectively give rise to CRC and cardiorespiratory dysautonomia. Moreover, there is also a need for better quantitative methods to assess CRC. This review addresses the current understanding of CRC by discussing: (1) the neurobiological basis of respiratory sinus arrhythmia (RSA); (2) various disease states involving cardiorespiratory dysautonomia; and (3) methodologies measuring heart rate variability and RSA. PMID:23497744
Second harmonic generation imaging of the collagen in myocardium for atrial fibrillation diagnosis
NASA Astrophysics Data System (ADS)
Tsai, Ming-Rung; Chiou, Yu-We; Sun, Chi-Kuang
2009-02-01
Myocardial fibrosis, a common sequela of cardiac hypertrophy, has been shown to be associated with arrhythmias in experimental models. Some research has indicated that myocardial fibrosis plays an important role in predisposing patients to atrial fibrillation. Second harmonic generation (SHG) is an optically nonlinear coherent process to image the collagen network. In this presentation, we observe the SHG images of the collagen matrix in atrial myocardium and we analyzed of collagen fibers arrangement by using Fourier-transform analysis. Moreover, comparing the SHG images of the collagen fibers in atrial myocardium between normal sinus rhythm (NSR) and atrial fibrillation (AF), our result indicated that it is possible to realize the relation between myocardial fibrosis and AF.
Gastric myoelectrical and autonomic cardiac reactivity to laboratory stressors
GIANAROS, PETER J.; QUIGLEY, KAREN S.; MORDKOFF, J. TOBY; STERN, ROBERT M.
2010-01-01
We evaluated the effects of two laboratory stressors (speech preparation and isometric handgrip) on gastric myoelectrical and autonomic cardiac activity, and the extent to which autonomic responses to these stressors and somatization predict reports of motion sickness during exposure to a rotating optokinetic drum. Both stressors prompted a decrease in preejection period (PEP) and respiratory sinus arrhythmia (RSA), and an increase in a dysrhythmic pattern of gastric myoelectrical activity, termed gastric tachyarrhythmia. Stressor-induced decreases in RSA and higher somatization scores predicted increased reports of motion sickness during drum rotation. These results demonstrate that laboratory stressors concurrently affect gastric myoelectrical activity and autonomic control of the heart, and that stressor-induced decreases in RSA and higher levels of somatization predict motion sickness susceptibility. PMID:11446577
Hibernation in black bears: independence of metabolic suppression from body temperature.
Tøien, Øivind; Blake, John; Edgar, Dale M; Grahn, Dennis A; Heller, H Craig; Barnes, Brian M
2011-02-18
Black bears hibernate for 5 to 7 months a year and, during this time, do not eat, drink, urinate, or defecate. We measured metabolic rate and body temperature in hibernating black bears and found that they suppress metabolism to 25% of basal rates while regulating body temperature from 30° to 36°C, in multiday cycles. Heart rates were reduced from 55 to as few as 9 beats per minute, with profound sinus arrhythmia. After returning to normal body temperature and emerging from dens, bears maintained a reduced metabolic rate for up to 3 weeks. The pronounced reduction and delayed recovery of metabolic rate in hibernating bears suggest that the majority of metabolic suppression during hibernation is independent of lowered body temperature.
Automated Detection of Atrial Fibrillation Based on Time-Frequency Analysis of Seismocardiograms.
Hurnanen, Tero; Lehtonen, Eero; Tadi, Mojtaba Jafari; Kuusela, Tom; Kiviniemi, Tuomas; Saraste, Antti; Vasankari, Tuija; Airaksinen, Juhani; Koivisto, Tero; Pankaala, Mikko
2017-09-01
In this paper, a novel method to detect atrial fibrillation (AFib) from a seismocardiogram (SCG) is presented. The proposed method is based on linear classification of the spectral entropy and a heart rate variability index computed from the SCG. The performance of the developed algorithm is demonstrated on data gathered from 13 patients in clinical setting. After motion artifact removal, in total 119 min of AFib data and 126 min of sinus rhythm data were considered for automated AFib detection. No other arrhythmias were considered in this study. The proposed algorithm requires no direct heartbeat peak detection from the SCG data, which makes it tolerant against interpersonal variations in the SCG morphology, and noise. Furthermore, the proposed method relies solely on the SCG and needs no complementary electrocardiography to be functional. For the considered data, the detection method performs well even on relatively low quality SCG signals. Using a majority voting scheme that takes five randomly selected segments from a signal and classifies these segments using the proposed algorithm, we obtained an average true positive rate of [Formula: see text] and an average true negative rate of [Formula: see text] for detecting AFib in leave-one-out cross-validation. This paper facilitates adoption of microelectromechanical sensor based heart monitoring devices for arrhythmia detection.
2011-01-01
Introduction Energy drinks and highly caffeinated drinks comprise some of the fastest growing products of the beverage industry, often targeting teenagers and young adults. Cardiac arrhythmias in children related to high caffeine consumption have not been well described in the literature. This case series describes the possible association between the consumption of highly caffeinated drinks and the subsequent development of atrial fibrillation in the adolescent population. Case presentations We report the cases of two Caucasian adolescent boys of 14 and 16 years of age at the time of presentation, each without a significant cardiac history, who presented with palpitations or vague chest discomfort or both after a recent history of excessive caffeine consumption. Both were found to have atrial fibrillation on electrocardiogram; one patient required digoxin to restore a normal sinus rhythm, and the other self-converted after intravenous fluid administration. Conclusion With the increasing popularity of energy drinks in the pediatric and adolescent population, physicians should be aware of the arrhythmogenic potential associated with highly caffeinated beverage consumption. It is important for pediatricians to understand the lack of regulation in the caffeine content and other ingredients of these high-energy beverages and their complications so that parents and children can be educated about the risk of cardiac arrhythmias with excessive energy drink consumption. PMID:21247417
Simons, G R; Newby, K H; Kearney, M M; Brandon, M J; Natale, A
1998-02-01
The objective of this study was to assess the safety and efficacy of transvenous low energy cardioversion of atrial fibrillation in patients with ventricular tachycardia and atrial fibrillation and to study the mechanisms of proarrhythmia. Previous studies have demonstrated that cardioversion of atrial fibrillation using low energy, R wave synchronized, direct current shocks applied between catheters in the coronary sinus and right atrium is feasible. However, few data are available regarding the risk of ventricular proarrhythmia posed by internal atrial defibrillation shocks among patients with ventricular arrhythmias or structural heart disease. Atrial defibrillation was performed on 32 patients with monomorphic ventricular tachycardia and left ventricular dysfunction. Shocks were administered during atrial fibrillation (baseline shocks), isoproterenol infusion, ventricular pacing, ventricular tachycardia, and atrial pacing. Baseline shocks were also administered to 29 patients with a history of atrial fibrillation but no ventricular arrhythmias. A total of 932 baseline shocks were administered. No ventricular proarrhythmia was observed after well-synchronized baseline shocks, although rare inductions of ventricular fibrillation occurred after inappropriate T wave sensing. Shocks administered during wide-complex rhythms (ventricular pacing or ventricular tachycardia) frequently induced ventricular arrhythmias, but shocks administered during atrial pacing at identical ventricular rates did not cause proarrhythmia. The risk of ventricular proarrhythmia after well-synchronized atrial defibrillation shocks administered during narrow-complex rhythms is low, even in patients with a history of ventricular tachycardia. The mechanism of proarrhythmia during wide-complex rhythms appears not to be related to ventricular rate per se, but rather to the temporal relationship between shock delivery and the repolarization time of the previous QRS complex.
Dronedarone: an amiodarone analogue.
Doggrell, Sheila A; Hancox, Jules C
2004-04-01
Of the antiarrhythmic drugs in current use, amiodarone is one of the most effective and is associated with a comparatively low risk of drug-induced pro-arrhythmia, probably due to its multiple pharmacological actions on cardiac ion channels and receptors. However, amiodarone is associated with significant extra-cardiac side effects and this has driven development of amiodarone analogues. These analogues include short acting analogues (e.g., AT-2001) with similar acute effects to amiodarone, the thyroid receptor antagonist KB-130015 and dronedarone. Dronedarone, (SR-33589; Sanofi-Synthelabo), is a non-iodinated amiodarone derivative that inhibits Na +, K + and Ca 2+ currents. It is a potent inhibitor of the acetylcholine-activated K + current from atrial and sinoatrial nodal tissue, and inhibits the rapid delayed rectifier more potently than slow and inward rectifier K + currents and inhibits L-type calcium current. Dronedarone is an antagonist at alpha- and beta-adrenoceptors and unlike amiodarone, has little effect at thyroid receptors. Dronedarone is more potent than amiodarone in inhibiting arrhythmias and death in animal models of ischaemia- and reperfusion-induced arrhythmias. In the Dronedarone Atrial Fibrillation Study After Electrical Cardioversion (DAFNE) clinical trial, dronedarone 800 mg/day appeared to be effective and safe for the prevention of atrial fibrillation relapses after cardioversion. The Antiarrhythmic Trial with Dronedarone in Moderate-to-Severe Congestive Heart Failure Evaluating Morbidity Decrease (ANDROMEDA) trial was stopped due to a potential increased risk of death in the dronedarone group. Trials of dronedarone in the maintenance of sinus rhythm in patients with atrial fibrillation and a safety and tolerability study in patients with an implantable cardioverter defibrillator are ongoing. Further experimental and clinical studies are required before we have a definitive answer to whether dronedarone has advantages over amiodarone and other amiodarone analogues.
Arrhythmia causes lipid accumulation and reduced glucose uptake.
Lenski, Matthias; Schleider, Gregor; Kohlhaas, Michael; Adrian, Lucas; Adam, Oliver; Tian, Qinghai; Kaestner, Lars; Lipp, Peter; Lehrke, Michael; Maack, Christoph; Böhm, Michael; Laufs, Ulrich
2015-01-01
Atrial fibrillation (AF) is characterized by irregular contractions of atrial cardiomyocytes and increased energy demand. The aim of this study was to characterize the influence of arrhythmia on glucose and fatty acid (FA) metabolism in cardiomyocytes, mice and human left atrial myocardium. Compared to regular pacing, irregular (pseudo-random variation at the same number of contractions/min) pacing of neonatal rat cardiomyocytes induced shorter action potential durations and effective refractory periods and increased diastolic [Ca(2+)]c. This was associated with the activation of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and AMP-activated protein kinase (AMPK). Membrane expression of fatty acid translocase (FAT/CD36) and (14)C-palmitic acid uptake were augmented while membrane expression of glucose transporter subtype 4 (GLUT-4) as well as (3)H-glucose uptake were reduced. Inhibition of AMPK and CaMKII prevented these arrhythmia-induced metabolic changes. Similar alterations of FA metabolism were observed in a transgenic mouse model (RacET) for spontaneous AF. Consistent with these findings samples of left atrial myocardium of patients with AF compared to matched samples of patients with sinus rhythm showed up-regulation of CaMKII and AMPK and increased membrane expression of FAT/CD36, resulting in lipid accumulation. These changes of FA metabolism were accompanied by decreased membrane expression of GLUT-4, increased glycogen content and increased expression of the pro-apoptotic protein bax. Irregular pacing of cardiomyocytes increases diastolic [Ca(2+)]c and activation of CaMKII and AMPK resulting in lipid accumulation, reduced glucose uptake and increased glycogen synthesis. These metabolic changes are accompanied by an activation of pro-apoptotic signalling pathways.
Analysis of Electrocardiograms Associated with Pediatric Electrical Burns.
McLeod, Jennifer S; Maringo, Alison E; Doyle, Patrick J; Vitale, Lisa; Klein, Justin D; Shanti, Christina M
2017-05-26
The purpose of this study was to examine the utility of electrocardiograms (EKGs) for low-risk, low-voltage pediatric electrical burn victims. A retrospective chart review was conducted on 86 pediatric patients who presented to the children's hospital between 2000 and 2015 after sustaining electrical burns. Variables included source and estimated voltage, extent of injuries, length of stay, high risk factors, and EKG results. High risk factors included estimated voltage > 1000 V, lightning, tetany, symptoms, loss of consciousness, or seizures. Statistical analyses were conducted. Average age was 5 years. Of those who sustained burns, 84.5% (n = 71/84) had second-degree burns ≤ 1% TBSA or less. Eleven patients had high risk factors, 12.9% (n = 11/85) and most had length of stay < 3 days (91.8%; n = 78/85). Majority sustained burns from low-voltage (< 300 V) household electrical outlets, cords, or light bulb sockets (90.4%; n = 75/83). Among patients with available EKGs, 12 had arrhythmias on initial EKG (i.e., low right atrial rhythm, t-wave inversions, sinus tachycardia, bundle branch block; 20.7%; n = 12/58). All were transient and nonfatal. The data suggest that low estimated voltage (< 300 V) electrical injuries were associated with negative EKGs; however, due to the low rate of arrhythmias, a Fisher's exact test did not show significance, P = 0.09 (P > 0.05). Preliminary data suggest that most pediatric electrical burns are due to low voltage (< 300 V) household sources. Few have high risk factors or arrhythmias that were transient and nonfatal. These data suggest that low-risk, asymptomatic, low-voltage pediatric electrical burns may not require an initial screening EKG.
Miller, Jonas G.; Nuselovici, Jacob N.; Hastings, Paul D.
2016-01-01
How does empathic physiology unfold as a dynamic process, and which aspect of empathy predicts children’s kindness? In response to empathy induction videos, 4–6 year-old children (N = 180) showed an average pattern of dynamic respiratory sinus arrhythmia (RSA) change characterized by early RSA suppression followed by RSA recovery, and modest subsequent suppression during positive resolution of the empathic event. Children’s capacity for this pattern of flexible RSA change was associated with their subjective empathic feelings, which were concurrently associated with more sympathetic and prosocial responses to others. Conversely, only children’s dynamic RSA change longitudinally predicted prosocial behavior two years later. These findings have implications for understanding the dynamic and multifaceted nature of empathy, and its relation with prosocial development. PMID:28262932
Cardiovascular function during sustained +G/z/ stress
NASA Technical Reports Server (NTRS)
Erickson, H. H.; Sandler, H.; Stone, H. L.
1976-01-01
The development of aerospace systems capable of very high levels of positive vertical accelerators stress has created a need for a better understanding of the cardiovascular responses to acceleration. Using a canine model, the heart and cardiovascular system were instrumented to continuously measure coronary blood flow, cardiac output, left ventricular and aortic root pressure, and oxygen saturation in the aorta, coronary sinus, and right ventricle. The animals were exposed to acceleration profiles up to +6 G, 120 s at peak G; a seatback angle of 45 deg was simulated in some experiments. Radiopaque contrast medium was injected to visualize the left ventricular chamber, coronary vasculature, aorta, and branches of the aorta. The results suggest mechanisms responsible for arrhythmias which may occur, and subendocardial hemorrhage which has been reported in other animals.
Sievers, H H; Weyand, M; Kraatz, E G; Bernhard, A
1991-04-01
The standard technique for orthotopic cardiac transplantation implies large atrial anastomoses which do not preserve the anatomical integrity of the donor atria. This may become a potential source of electrophysiological and mechanical atrial dysfunction, especially in the right atrium with the sinus node and the sensitive low-pressure atrioventricular valve. As an improvement we suggest an alternative technique which we have recently developed for orthotopic cardiac transplantation; it combines the simple, convenient left atrial connection of the standard technique with individual anastomoses of the superior and inferior venae cavae, preserving the right atrium of the donated heart intact. This technique and our first results in two cases are described. Postoperatively, no arrhythmias and no signs of tricuspid insufficiency were observed.
Marital Conflict, Allostatic Load, and the Development of Children's Fluid Cognitive Performance
Hinnant, J. Benjamin; El-Sheikh, Mona; Keiley, Margaret; Buckhalt, Joseph A.
2013-01-01
Relations between marital conflict, children’s respiratory sinus arrhythmia (RSA), and fluid cognitive performance were examined over three years to assess allostatic processes. Participants were 251 children reporting on marital conflict, baseline RSA and RSA reactivity to a lab challenge were recorded, and fluid cognitive performance was measured using the Woodcock-Johnson III. A cross-lagged model showed that higher levels of marital conflict at age 8 predicted weaker RSA-R at age 9 for children with lower baseline RSA. A growth model showed that lower baseline RSA in conjunction with weaker RSA-R predicted the slowest development of fluid cognitive performance. Findings suggest that stress may affect development of physiological systems regulating attention, which are tied to the development of fluid cognitive performance. PMID:23534537
Pathogenesis of sudden death following water immersion (immersion syndrome)
NASA Technical Reports Server (NTRS)
Buhring, M.; Spies, H. F.
1981-01-01
Sympathetic activity under cold stress is investigated. Predominantly vagal cardio-depressive reflexes are discussed besides currently known mechanisms of sudden death after water immersion. Pronounced circulatory centralization in diving animals as well as following exposure in cold water indicates additional sympathetic activity. In cold water baths of 15 C, measurements indicate an increase in plasma catecholamine levels by more than 300 percent. This may lead to cardiac arrhythmias by the following mechanisms: cold water essentially induces sinus bradycardia; brady-and tachycardiarrhythmias may supervene as secondary complications; sinusbradycardia may be enhanced by sympathetic hypertonus. Furthermore, ectopic dysrhythmias are liable to be induced by the strictly sympathetic innervation of the ventricle. Myocardial ischemia following a rise in peripheral blood pressure constitutes another arrhythmogenic factor. Some of these reactions are enhanced by alcohol intoxication.
Altenburg, J; de Graaff, C S; van der Werf, T S; Boersma, W G
2011-01-01
The available evidence for long-term, low-dose treatment with 14- and 15-membered ring macrolides in non-cystic fibrosis (CF) bronchiectasis, COPD, chronic sinusitis, and asthma is reviewed with special attention to possible adverse effects and the emergence of resistance during long-term macrolide treatment. Macrolide maintenance therapy has been proven to be of benefit in diffuse panbronchiolitis and CF, presumably due to an anti-inflammatory mechanism of action in addition to its direct antimicrobial effect. Solid evidence to justify this treatment regimen for non-CF bronchiectasis, asthma, or sinusitis is still lacking, although a beneficial effect of long-term macrolide therapy has been found in small clinical trials on these subjects. Data from randomized trials of long-term macrolide treatment in COPD are conflicting. A sufficiently long duration of treatment and the careful selection of patients appears to be crucial. Aside from its beneficial effects, possible side effects of macrolide treatment should be taken into account, the most important of these being gastrointestinal upset and cardiac arrhythmias. Development of macrolide resistance among respiratory pathogens is very common during long-term macrolide treatment. Whether this finding is clinically significant is a matter of debate. Copyright © 2010 S. Karger AG, Basel.
Safety and efficacy of vernakalant for acute cardioversion of atrial fibrillation: an update
Tsuji, Yukiomi; Dobrev, Dobromir
2013-01-01
Intravenous vernakalant has recently been approved in Europe as an atrial-selective antiarrhythmic drug for the conversion of recent-onset atrial fibrillation (AF). It inhibits atrial-selective K+ currents (IK,ACh and IKur) and causes rate-dependent atrial-predominant Na+ channel block, with only a small inhibitory effect on the rapid delayed rectifier K+ current (IKr) in the ventricle. Due to its atrial-selective properties, vernakalant prolongs the effective refractory period of the atria with minimal effects on the ventricles, being associated with a low proarrhythmic risk for torsades de pointes arrhythmias. Five pivotal clinical trials consistently demonstrated that vernakalant rapidly terminates AF with stable maintenance of sinus rhythm for up to 24 hours. A head-to-head comparative trial showed that the 90-minute conversion rate of vernakalant was substantially higher than that of amiodarone. Initially, a longer-acting oral formulation of vernakalant was shown to be effective and safe in preventing AF recurrence after cardioversion in a Phase IIb study. However, the clinical studies testing oral vernakalant for maintenance of sinus rhythm after AF cardioversion were prematurely halted for undisclosed reasons. This review article provides an update on the safety and efficacy of intravenous vernakalant for the rapid cardioversion of AF. PMID:23637539
Symptomatic arrhythmias due to syringomyelia-induced severe autonomic dysfunction.
Riedlbauchová, Lucie; Nedělka, Tomáš; Schlenker, Jakub
2014-10-01
Syringomyelia is characterized by cavity formation in the spinal cord, most often at C2-Th9 level. Clinical manifestation reflects extent and localization of the spinal cord injury. 20-year old woman was admitted for recurrent rest-related presyncopes with sudden manifestation. Paroxysms of sinus bradycardia with SA and AV blocks were repeatedly documented during symptoms. There was normal echocardiographic finding, (para) infectious etiology was not proved. Character of the ECG findings raised suspicion on neurogenic cause. Autonomic nervous system testing demonstrated abnormalities reflecting predominant sympathetic dysfunction. Suspicion on incipient myelopathy was subsequently confirmed by MRI, which discovered syringomyelia at Th5 level as the only pathology. A 52-year old man with hypotrophic quadruparesis resulting from perinatal brain injury was sent for 2-years lasting symptoms (sudden palpitation, sweating, muscle tightness, shaking) with progressive worsening. Symptoms occurred in association with sudden increase of sinus rhythm rate and blood pressure that were provoked by minimal physical activity. Presence of significant autonomic dysregulation with baroreflex hyperreactivity in orthostatic test and symptomatic postural orthostatic tachycardia with verticalization-associated hypertension were proved. MRI revealed syringomyelia at C7 and Th7 level affecting sympathetic centers at these levels. Sympathetic fibers dysfunction at C-Th spinal level may cause significant autonomic dysfunction with arrhythmic manifestation.
Predicting the risk of sudden cardiac death.
Lerma, Claudia; Glass, Leon
2016-05-01
Sudden cardiac death (SCD) is the result of a change of cardiac activity from normal (typically sinus) rhythm to a rhythm that does not pump adequate blood to the brain. The most common rhythms leading to SCD are ventricular tachycardia (VT) or ventricular fibrillation (VF). These result from an accelerated ventricular pacemaker or ventricular reentrant waves. Despite significant efforts to develop accurate predictors for the risk of SCD, current methods for risk stratification still need to be improved. In this article we briefly review current approaches to risk stratification. Then we discuss the mathematical basis for dynamical transitions (called bifurcations) that may lead to VT and VF. One mechanism for transition to VT or VF involves a perturbation by a premature ventricular complex (PVC) during sinus rhythm. We describe the main mechanisms of PVCs (reentry, independent pacemakers and abnormal depolarizations). An emerging approach to risk stratification for SCD involves the development of individualized dynamical models of a patient based on measured anatomy and physiology. Careful analysis and modelling of dynamics of ventricular arrhythmia on an individual basis will be essential in order to improve risk stratification for SCD and to lay a foundation for personalized (precision) medicine in cardiology. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.
Li, Yi-gang; Grönefeld, Gerian; Israel, Carsten; Lu, Shang-biao; Wang, Qun-shan; Hohnloser, Stefan H
2006-12-20
Atrial tachycardia or flutter is common in patients after orthotopic heart transplantation. Radiofrequency catheter ablation to treat this arrhythmia has not been well defined in this setting. This study was conducted to assess the incidence of various symptomatic atrial arrhythmias and the efficacy and safety of radiofrequency catheter ablation in these patients. Electrophysiological study and catheter ablation were performed in patients with symptomatic tachyarrhythmia. One Halo catheter with 20 poles was positioned around the tricuspid annulus of the donor right atrium, or positioned around the surgical anastomosis when it is necessary. Three quadripolar electrode catheters were inserted via the right or left femoral vein and positioned in the recipient atrium, the bundle of His position, the coronary sinus. Programmed atrial stimulation and burst pacing were performed to prove electrical conduction between the recipient and the donor atria and to induce atrial arrhythmias. Out of 55 consecutive heart transplantation patients, 6 males [(58 +/- 12) years] developed symptomatic tachycardias at a mean of (5 +/- 4) years after heart transplantation. Electrical propagation through the suture line between the recipient and the donor atrium was demonstrated during atrial flutter or during recipient atrium and donor atrium pacing in 2 patients. By mapping around the suture line, the earliest fragmented electrogram of donor atrium was assessed. This electrical connection was successfully ablated in the anterior lateral atrium in both patients. There was no electrical propagation through the suture line in the other 4 patients. Two had typical atrial flutter in the donor atrium which was successfully ablated by completing a linear ablation between the tricuspid annulus and the inferior vena cava. Two patients had atrial tachycardia which was ablated in the anterior septal and lateral donor atrium. There were no procedure-related complications. Patients were free of recurrent atrial tachyarrhythmias after a follow-up of (8 +/- 7) months. Four electrophysiological mechanisms have been found to contribute to the occurrence of symptomatic supraventricular arrhythmias following heart transplantation. Radiofrequency catheter ablation in patients with atrial flutter/tachycardia is feasible and safe after heart transplantation.
HRV strongly depends on breathing. Are we questioning the right suspect?
Buchner, Teodor
2011-01-01
The fact that the heart rate variability (HRV) depends on breathing is well known. The HRV is an important phenomenon which reflects the functional state of the autonomous nervous system (ANS), although there are some doubts concerning the actual interpretation of spectral components of HRV and their postulated balance. The assessment of the functional state of the ANS is the task of paramount importance in risk stratification of cardiological patients. HRV is considered to depend mainly on the properties of the sinus node (SN), which achieves neurohumoral input from the ANS. Interestingly, there is growing evidence that the relation between the heart rate (HR) and breathing rate (BR) is really strong. The variety of breathing-related effects that are present in HRV is very rich, including respiratory sinus arrhythmia (RSA), cardiorespiratory synchronization and vivid heart rate response to breathing disorders. If the mean frequency of any of rhythms is changed, the other rhythm adjusts itself. This provokes the question on the actual source of the dynamics observed in the HRV. Is it possible that we observe mainly the dynamics of the respiratory rhythm which is just transduced by the heart effector? What might be the role of the intrinsic dynamics of this effector? Is the RSA a product of neural regulation or rather a by-product: what is its teleological role? In consequence: if we concentrate on the sinus node and its properties in order to understand the nature of the HRV - are we questioning the right suspect? The reasoning is supplied by suitable choice of literature and by the analysis of the computational model. Various consequences are discussed.
Modified radial v/s biatrial maze for atrial fibrillation in rheumatic valvular heart surgery.
Sayed, Sajid A; Katewa, Ashish; Srivastava, Vivek; Jana, Sujit; Patwardhan, Anil M
2014-01-01
Atrial fibrillation (AF) is commonest sustained atrial arrhythmia producing high morbidity. Although Cox's Maze III procedure cures AF in majority, reduced atrial transport function (ATF) is a concern. Radial approach with ablation lines radial from sinus node towards atrioventricular annulii and parallel to atrial coronary arteries, has shown better ATF. Single blind open randomized prospective study of 80 patients was undertaken in two groups (40 each) of modified Cox's maze III and modified radial approach, to evaluate conversion to normal sinus rhythm (NSR) and ATF. Patients undergoing surgery for rheumatic valvular heart disease with continuous AF were prospectively randomized. Ablation lines were created with radiofrequency (RF) bipolar coagulation with cryoablation for the isthmal lesions and coronary sinus. Results were compared at 6 months and ATF was evaluated by atrial filling fraction (AFF) and A/E ratio on echocardiography. The rate of conversion to NSR in both groups was statistically insignificant by Fisher's exact test (p > 0.05). ATF was better in modified radial approach compared to modified Cox's Maze III (A/E compared by unpaired t test:0.52 ± 0.08 v/s 0.36 ± 0.10; p < 0.05. AFF compared using Mann Whitney U test: median AFF for radial group was 23 v/s 20 for biatrial group; p < 0.05). In patients with AF undergoing rheumatic valvular surgery, radiofrequency radial approach is as effective as modified Cox's maze III for conversion to NSR with better atrial transport function. Copyright © 2014 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.
Jastrzębski, Jan; Kępka, Cezary; Kruk, Mariusz; Demkow, Marcin; Kalińczuk, Łukasz; Wolny, Rafał; Ciszewski, Michał; Michałowska, Ilona; Witkowski, Adam
2013-01-01
Introduction Heart rate irregularities are the major limitations of computed tomographic coronary angiography (CTCA) due to severe motion artifacts. Aim To evaluate the safety and efficacy of a lidocaine intravenous bolus in preserving good image quality by the transient suppression of premature ventricular contractions (PVC) during the CTCA scan. Material and methods The study group comprised 67 consecutive patients with sinus rhythm and numerous PVC scheduled for CTCA. Intravenous boluses of 25–50 mg lidocaine were given after calcium score assessment and immediately before CTCA. The control group comprised 67 patients with sinus rhythm without PVC matched according to the body mass index (BMI), age, sex, and calcium score. All coronary vessel segments were assessed for image quality and presence of significant stenosis. Results As compared with calcium score assessment, after administration of lidocaine and during the CTCA scan PVC were completely suppressed in 22 (40%), reduced in 10 (18%), unchanged in 18 (32%), and intensified in 5 (10%) patients. Overall, there were 32 (58%) patients with sinus rhythm during CTCA as compared with only 11 (20%) patients free from PVC during calcium score assessment (p < 0.001). Image quality in 871 coronary segments including both the study group and control patients was worse in patients with PVC (p < 0.0001). However, there was no statistically significant difference in the number of patients with at least one segment of non-diagnostic quality (6% vs. 12%, p = 0.36; respectively). Conclusions Single lidocaine bolus given prior to CTCA is safe, may temporarily eliminate or reduce the intensity of arrhythmia, and hence results in improved quality of CTCA in patients with numerous PVC. PMID:24570719
Atienza, Felipe; Almendral, Jesús; Jalife, José; Zlochiver, Sharon; Ploutz-Snyder, Robert; Torrecilla, Esteban G; Arenal, Angel; Kalifa, Jérôme; Fernández-Avilés, Francisco; Berenfeld, Omer
2009-01-01
Spectral analysis identifies localized sites of high-frequency activity during atrial fibrillation (AF). This study sought to determine the effectiveness of using real-time dominant frequency (DF) mapping for radiofrequency ablation of maximal DF (DFmax) sites and elimination of left-to-right frequency gradients in the long-term maintenance of sinus rhythm (SR) in AF patients. DF mapping was performed in 50 patients during ongoing AF (32 paroxysmal, 18 persistent), acquiring a mean of 117 +/- 38 points. Ablation was performed targeting DFmax sites, followed by circumferential pulmonary vein isolation. Ablation significantly reduced DFs (Hz) in the LA (7.9 +/- 1.4 vs. 5.7 +/- 1.3, P <.001), coronary sinus (CS) (5.7 +/- 1.1 vs. 5.3 +/- 1.2, P = .006), and RA (6.3 +/- 1.4 vs. 5.4 +/- 1.3, P <.001) abolishing baseline left-to-right atrial DF gradient (1.7 +/- 1.7 vs. 0.2 +/- 0.9; P <.001). Only a significant reduction in DFs in all chambers with a loss of the left-to-right atrial gradient after ablation was associated with a higher probability of long-term SR maintenance in both paroxysmal and persistent AF patients. After a mean follow-up of 9.3 +/- 5.4 months, 88% of paroxysmal and 56% of persistent AF patients were free of AF (P = .02). Ablation of DFmax sites was associated with a higher probability of remaining both free of arrhythmias (78% vs. 20%; P = .001) and free of AF (88% vs. 30%; P <.001). Radiofrequency ablation leading to elimination of LA-to-RA frequency gradients predicts long-term SR maintenance in AF patients.
Schotten, Ulrich; de Haan, Sunniva; Neuberger, Hans-Ruprecht; Eijsbouts, Sabine; Blaauw, Yuri; Tieleman, Robert; Allessie, Maurits
2004-11-01
Atrial fibrillation (AF) induces a progressive dilatation of the atria which in turn might promote the arrhythmia. The mechanism of atrial dilatation during AF is not known. To test the hypothesis that loss of atrial contractile function is a primary cause of atrial dilatation during the first days of AF, eight goats were chronically instrumented with epicardial electrodes, a pressure transducer in the right atrium, and piezoelectric crystals to measure right atrial diameter. AF was induced with the use of repetitive burst pacing. Atrial contractility was assessed during sinus rhythm, atrial pacing (160-, 300-, and 400-ms cycle length), and electrically induced AF. The compliance of the fibrillating right atrium was measured during unloading the atria with diuretics and loading with 1 liter of saline. All measurements were repeated after 6, 12, and 24 h of AF and then once a day during the first 5 days of AF. Recovery of the observed changes after spontaneous cardioversion was also studied. After 5 days of AF, atrial contractility during sinus rhythm or slow atrial pacing was greatly reduced. During rapid pacing (160 ms) or AF, the amplitude of the atrial pressure waves had declined to 20% of control. The compliance of the fibrillating atria increased twofold, whereas the right atrial pressure was unchanged. As a result, the mean right atrial diameter increased by approximately 12%. All changes were reversible within 3 days of sinus rhythm. We conclude that atrial dilatation during the first days of AF is due to an increase in atrial compliance caused by loss of atrial contractility during AF. Atrial compliance and size are restored when atrial contractility recovers after cardioversion of AF.
Oda, Sam Goldy Shoyama; Yamato, Ronaldo Jun; Fedullo, José Daniel Luzes; Leomil Neto, Moacir; Larsson, Maria Helena Matiko Akao
2009-09-01
Thirty-three captive leopard cats, Leopardus tigrinus, were anesthetized with xylazine (1-2 mg/kg) and ketamine (10 mg/kg), and electrocardiograph (ECG) tests were recorded in all leads with 1 cm = 1 mV sensibility and 25 mm/sec speed repeating DII lead at 50 mm/sec speed with the same sensibility. Results expressed by mean and standard deviation were: heart rate (HR) = 107 +/- 17 (bpm); P-wave = 0.048 +/- 0.072 (s) x 0.128 +/- 0.048 (mV); PR interval = 0.101 +/- 0.081 (s); QRS compound = 0.053 +/- 0.012 (s) x 1.446 +/- 0.602 (mV); QT interval = 0.231 +/- 0.028 (s); R-wave (CV6LL) = 1.574 +/- 0.527 (mV); R-wave (CV6LU) = 1.583 +/- 0.818 (mV); heart rhythm: normal sinus rhythm (15.2%), sinus rhythm with wandering pacemaker (WPM) (60.6%), sinus arrhythmia with WPM (24.2%); electric axis: between +30 degrees and +60 degrees (6.1%), +60 (6.1%), between +60 degrees and +90 degrees (57.6%), +90 degrees (9%), between +90 degrees and +120 degrees (21.2%); ST segment: normal (75.7%), elevation (18.2%), depression (6.1%); T-wave polarity (DII): positive (100%); T-wave (V10): absent (6.1%), negative (63.6%), positive (18.2%), and with interference (12.1%). Through ECG data comparison with other species, unique features of Leopardus tigrinus' (leopard cat) ECG parameters were detected. Some of the study animals presented with an R-wave amplitude that was indicative of left ventricle overload according to patterns for normal domestic cats (Felis cati). Echocardiographic exams revealed normal heart cavities' function and morphology. The aim of this study was to establish some electrocardiographic parameters of captive L. tigrinus.
Di Marco, Luigi Yuri; Raine, Daniel; Bourke, John P; Langley, Philip
2013-09-01
Successful termination of atrial fibrillation (AF) during catheter ablation (CA) is associated with arrhythmia-free follow-up. Preablation factors such as mean atrial fibrillation cycle length (AFCL) predict the likelihood of AF termination during ablation but recurring patterns and AFCL stability have not been evaluated. To investigate novel predictors of acute and postoperative ablation outcomes from intracardiac electrograms: (1) recurring AFCL patterns and (2) localization index (LI) of the instantaneous fibrillatory rate distribution. Sixty-two patients with AF (32 paroxysmal AF; 45 men; age 57 ± 10 years) referred for CA were enrolled. One-minute electrogram was recorded from coronary sinus (CS; 5 bipoles) and right atrial appendage (HRA; 2 bipoles). Atrial activations were detected automatically to derive the AFCL and instantaneous fibrillatory rate (inverse of AFCL) time series. Recurring AFCL patterns were quantified by using recurrence plot indices (RPIs): percentage determinism, entropy of determinism, and maximum diagonal length. AFCL stability was determined by using the LI. The CA outcome predictivity of individual indices was assessed. Patients with terminated atrial fibrillation (T-AF) had higher RPI (P < .05 in CS7-8) and LI than did those with nonterminated atrial fibrillation (P < .005 in CS3-4; P < .05 in CS5-6, CS7-8, and HRA). Patients free of arrhythmia after 3-month follow-up had higher RPI and LI (all P < .05 in CS7-8). All indices except percentage determinism predicted T-AF in CS7-8 (area under the curve [AUC] ≥ 0.71; odds ratio [OR] ≥ 4.50; P < .05). The median AFCL and LI predicted T-AF in HRAD (AUC ≥ 0.75; OR ≥ 7.76; P < .05). The RPI and LI predicted 3-month follow-up in CS7-8 (AUC ≥ 0.68; OR ≥ 4.17; P < .05). AFCL recurrence and stability indices could be used in selecting patients more likely to benefit from CA. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
The physiological effects of slow breathing in the healthy human
Russo, Marc A.; Santarelli, Danielle M.; O’Rourke, Dean
2017-01-01
Slow breathing practices have been adopted in the modern world across the globe due to their claimed health benefits. This has piqued the interest of researchers and clinicians who have initiated investigations into the physiological (and psychological) effects of slow breathing techniques and attempted to uncover the underlying mechanisms. The aim of this article is to provide a comprehensive overview of normal respiratory physiology and the documented physiological effects of slow breathing techniques according to research in healthy humans. The review focuses on the physiological implications to the respiratory, cardiovascular, cardiorespiratory and autonomic nervous systems, with particular focus on diaphragm activity, ventilation efficiency, haemodynamics, heart rate variability, cardiorespiratory coupling, respiratory sinus arrhythmia and sympathovagal balance. The review ends with a brief discussion of the potential clinical implications of slow breathing techniques. This is a topic that warrants further research, understanding and discussion. Key points Slow breathing practices have gained popularity in the western world due to their claimed health benefits, yet remain relatively untouched by the medical community. Investigations into the physiological effects of slow breathing have uncovered significant effects on the respiratory, cardiovascular, cardiorespiratory and autonomic nervous systems. Key findings include effects on respiratory muscle activity, ventilation efficiency, chemoreflex and baroreflex sensitivity, heart rate variability, blood flow dynamics, respiratory sinus arrhythmia, cardiorespiratory coupling, and sympathovagal balance. There appears to be potential for use of controlled slow breathing techniques as a means of optimising physiological parameters that appear to be associated with health and longevity, and that may extend to disease states; however, there is a dire need for further research into the area. Educational aims To provide a comprehensive overview of normal human respiratory physiology and the documented effects of slow breathing in healthy humans. To review and discuss the evidence and hypotheses regarding the mechanisms underlying slow breathing physiological effects in humans. To provide a definition of slow breathing and what may constitute “autonomically optimised respiration”. To open discussion on the potential clinical implications of slow breathing techniques and the need for further research. PMID:29209423
Powell, Brian D; Saxon, Leslie A; Boehmer, John P; Day, John D; Gilliam, F Roosevelt; Heidenreich, Paul A; Jones, Paul W; Rousseau, Matthew J; Hayes, David L
2013-10-29
This study sought to determine if the risk of mortality associated with inappropriate implantable cardioverter-defibrillator (ICD) shocks is due to the underlying arrhythmia or the shock itself. Shocks delivered from ICDs are associated with an increased risk of mortality. It is unknown if all patients who experience inappropriate ICD shocks have an increased risk of death. We evaluated survival outcomes in patients with an ICD and a cardiac resynchronization therapy defibrillator enrolled in the LATITUDE remote monitoring system (Boston Scientific Corp., Natick, Massachusetts) through January 1, 2010. First shock episode rhythms from 3,809 patients who acutely survived the initial shock were adjudicated by 7 electrophysiologists. Patients with a shock were matched to patients without a shock (n = 3,630) by age at implant, implant year, sex, and device type. The mean age of the study group was 64 ± 13 years, and 78% were male. Compared with no shock, there was an increased rate of mortality in those who received their first shock for monomorphic ventricular tachycardia (hazard ratio [HR]: 1.65, p < 0.0001), ventricular fibrillation/polymorphic ventricular tachycardia (HR: 2.10, p < 0.0001), and atrial fibrillation/flutter (HR: 1.61, p = 0.003). In contrast, mortality after first shocks due to sinus tachycardia and supraventricular tachycardia (HR: 0.97, p = 0.86) and noise/artifact/oversensing (HR: 0.91, p = 0.76) was comparable to that in patients without a shock. Compared with no shock, those who received their first shock for ventricular rhythms and atrial fibrillation had an increased risk of death. There was no significant difference in survival after inappropriate shocks for sinus tachycardia or noise/artifact/oversensing. In this study, the adverse prognosis after first shock appears to be more related to the underlying arrhythmia than to an adverse effect from the shock itself. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Lerma, Claudia; Gorelick, Alexander; Ghanem, Raja N; Glass, Leon; Huikuri, Heikki V
2013-09-01
To identify potential new markers for assessing the risk of sudden arrhythmic events based on a method that captures features of premature ventricular complexes (PVCs) in relation to sinus RR intervals in Holter recordings (heartprint). Holter recordings obtained 6 weeks after acute myocardial infarction from 227 patients with reduced ventricular function (left ventricular ejection fraction ≤ 40%) were used to produce heartprints. Measured indices were: PVCs per hour, standard deviation of coupling interval (SDCI), and the number of occurrences of the most prevalent form of PVCs (SNIB). Predictive values, survival analysis, and Cox regression with adjustment for clinical variables were performed based on primary endpoint, defined as an electrocardiogram-documented fatal or near-fatal arrhythmic event, death from any cause, and cardiac death. High ectopy (PVCs per hour ≥10) was a predictor of all endpoints. Repeating forms of PVCs (SNIB ≥ 83) was a predictor of primary endpoint, hazard ratio = 3.5 (1.3-9.5), and all-cause death, hazard ratio = 2.8 (1.1-7.3), but not cardiac death. SDCI ≤ 80 ms was a predictor of all-cause death and cardiac death, but not of primary endpoint. High ectopy, prevalence of repeating forms of PVCs, and low coupling interval variability are potentially useful risk markers of fatal or near-fatal arrhythmias after myocardial infarction.
RSA fluctuation in major depressive disorder.
Rottenberg, Jonathan; Clift, April; Bolden, Sarah; Salomon, Kristen
2007-05-01
Cardiac vagal control, as measured by indices of respiratory sinus arrhythmia (RSA), has been investigated as a marker of impaired self-regulation in mental disorders, including depression. Past work in depressed samples has focused on deficits in resting RSA levels, with mixed results. This study tested the hypothesis that depression involves abnormal RSA fluctuation. RSA was measured in depressed and healthy control participants during rest and during two reactivity tasks, each followed by a recovery period. Relative to controls, depressed persons exhibited lower resting RSA levels as well as less RSA fluctuation, primarily evidenced by a lack of task-related vagal suppression. Group differences in RSA fluctuation were not accounted for by differences in physical health or respiration, whereas group differences in resting RSA level did not survive covariate analyses. Depression may involve multiple deficits in cardiac vagal control.
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
Obradović, Jelena; Bush, Nicole R.; Stamperdahl, Juliet; Adler, Nancy E.; Boyce, W. Thomas
2009-01-01
This study examined the direct and interactive effects of stress reactivity and family adversity on socio-emotional and cognitive development in 338 five-to-six-year-old children. Neurobiological stress reactivity was measured as respiratory sinus arrhythmia and salivary cortisol responses to social, cognitive, sensory, and emotional challenges. Adaptation was assessed using child, parent, and teacher reports of externalizing symptoms, prosocial behaviors, school engagement, and academic competence. Results revealed significant interactions between reactivity and adversity. High stress reactivity was associated with more maladaptive outcomes in the context of high adversity but with better adaption in the context of low adversity. The findings corroborate a reconceptualization of stress reactivity as biological sensitivity to context by showing that high reactivity can both hinder and promote adaptive functioning. PMID:20331667
Moskowitz, Lauren J; Walsh, Caitlin E; Mulder, Emile; McLaughlin, Darlene Magito; Hajcak, Greg; Carr, Edward G; Zarcone, Jennifer R
2017-12-01
There is little research on the functional assessment and treatment of anxiety and related problem behavior in children with autism spectrum disorder (ASD), particularly those with intellectual and developmental disability (IDD). In a recent study, we evaluated a multimethod strategy for assessing anxiety in children with ASD and IDD (Am J Intellect Dev Disabil 118:419-434, 2013). In the present study, we developed treatments for the anxiety and associated problem behavior in these same children. A multiple baseline design was used to evaluate the effectiveness of a multicomponent intervention package, incorporating individualized strategies from Positive Behavior Support and Cognitive Behavioral Therapy. During intervention, all three participants showed substantial decreases in anxiety and problem behavior and significant increases in respiratory sinus arrhythmia in the situations that had previously been identified as anxiety-provoking.
Effects of novel oral anticoagulants on left atrial and left atrial appendage thrombi: an appraisal.
Marsico, Fabio; Cecere, Milena; Parente, Antonio; Paolillo, Stefania; de Martino, Fabiana; Dellegrottaglie, Santo; Trimarco, Bruno; Perrone Filardi, Pasquale
2017-02-01
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and predisposes to an increased risk of thromboembolic events. Patients affected by AF exhibit an increased risk of stroke compared with those in sinus rhythm, with the most common location of thrombi in the left atrial appendage. Until 2009, warfarin and other vitamin K antagonists were the only class of oral anticoagulants available. More recently, dabigatran, rivaroxaban, apixaban, and edoxaban have been approved by regulatory authorities for prevention of stroke in patients with non-valvular AF. Few data are available about the efficacy of novel oral anticoagulants for the treatment of left atrial and left atrial appendage thrombosis. Aim of this review is to summarize available evidence regarding the effectiveness of novel oral anticoagulants on left atrial appendage thrombosis.
Child and maternal attachment predict school-aged children's psychobiological convergence.
Sichko, Stassja; Borelli, Jessica L; Smiley, Patricia A; Goldstein, Alison; Rasmussen, Hannah F
2018-06-24
Psychobiological convergence-the alignment of task-related changes in children's self-reported and physiological indices of reactivity-has recently emerged as a powerful correlate of children's attachment representations, but has not been explored for its association with children's self-reported attachment, with parents' attachment, or with respect to cardiovascular reactivity. The present study found that, within a diverse community sample of mothers and school-aged children (N = 104, M age = 10.31), the positive link between cardiovascular (respiratory sinus arrhythmia [RSA]) and subjective reactivity to a stressor was only significant among children with high levels of security and children of mothers with low levels of attachment avoidance and anxiety. The convergence of children's subjective and physiological experience is discussed as a key developmental competence that may lay the groundwork for effective coping. © 2018 Wiley Periodicals, Inc.
Chandra, Dinesh; Gupta, Anubhav; Nath, Ranjit K.; kazmi, Aamir; Grover, Vijay; Gupta, Vijay K.
2013-01-01
Background The anatomical variability in patients with anomalous pulmonary venous connection to superior vena cava presents a surgical challenge. The problem is further compounded by the common occurrence of postoperative complications like arrhythmias and obstruction of the superior vena cava or pulmonary veins. We present our experience of managing this subset using the two patch and Warden's techniques. Patients and methods Between June 2011 and September 2012, 7 patients with APVC to the SVC were operated in our institute. After delineating the anatomy, five of them had a two patch repair and two were managed with Warden's technique. Results There was no in-hospital mortality or early mortality over a mean follow-up of 9.66 ± 3.88 months (range 6–15 months). All the patients on follow-up had unobstructed pulmonary venous and SVC drainage on echocardiography and all of them were in normal sinus rhythm. Conclusions Anomalous pulmonary venous connection to superior vena cava is a challenging subset of patients in whom the surgical management needs to be individualized. The detailed anatomy must be delineated using echocardiography with or without CT angiography before deciding the surgical plan. This entity can be repaired with excellent immediate and early results. However, these patients must be closely followed up for complications like systemic and pulmonary venous obstruction and sinus node dysfunction. PMID:24206880
Roffe, C.; Fletcher, S.; Woods, K. L.
1994-01-01
OBJECTIVE--To examine the effect of doubling serum magnesium concentration on the incidence of arrhythmias in patients with suspected acute myocardial infarction. DESIGN--Randomised double blind clinical trial. SETTING--Coronary care unit of a teaching hospital. PATIENTS--Clinical data were collected on 2316 randomised patients with suspected acute myocardial infarction. Holter monitoring was performed in a subgroup of 70 patients and analysed in 48 patients in whom acute myocardial infarction was confirmed. INTERVENTIONS--By random allocation, patients received either an intravenous loading dose of 8 mmol magnesium sulphate over five minutes plus 65 mmol over the next 24 hours, or equal volumes of saline. MAIN OUTCOME MEASURES--(a) Clinically documented arrhythmias; (b) use of antiarrhythmic treatments, cardioversion, and insertion of a pacemaker; (c) incidence of all abnormal rhythms during Holter monitoring. RESULTS--In the main trial the incidence of rhythm disturbance while in the coronary care unit (expressed as the odds ratio (OR) for magnesium: placebo and its 95% confidence interval) was not significantly different between treatment groups for ventricular fibrillation (OR 0.74; 0.46 to 1.20), ventricular tachycardia (OR 0.87; 0.63 to 1.20), supraventricular tachycardia (OR 0.69; 0.38 to 1.26), atrial fibrillation (OR 0.92; 0.69 to 1.23), or heart block of any degree (OR 1.17; 0.83 to 1.65). Sinus bradycardia was significantly more common in the magnesium group (OR 1.38; 1.03 to 1.85; p = 0.02). These findings were corroborated by the use of treatments for rhythm disturbance and the data from Holter monitoring. CONCLUSION--The regimen of intravenous magnesium sulphate used here had no significant effect on arrhythmia in acute myocardial infarction. The reduction in mortality that has been shown with this form of treatment is not attributable to suppression of life threatening rhythm disturbances. PMID:8130021
Diagnosis and Treatment of Atrial Fibrillation.
Gutierrez, Cecilia; Blanchard, Daniel G
2016-09-15
Atrial fibrillation is a supraventricular arrhythmia that adversely affects cardiac function and increases the risk of stroke. It is the most common arrhythmia and a major source of morbidity and mortality; its prevalence increases with age. Pulse rate is sensitive, but not specific, for diagnosis, and suspected atrial fibrillation should be confirmed with 12-lead electrocardiography. Because normal electrocardiographic findings do not rule out atrial fibrillation, home monitoring is recommended if there is clinical suspicion of arrhythmia despite normal test results. Treatment is based on decisions made regarding when to convert to normal sinus rhythm vs. when to treat with rate control, and, in either case, how to best reduce the risk of stroke. For most patients, rate control is preferred to rhythm control. Ablation therapy is used to destroy abnormal foci responsible for atrial fibrillation. Anticoagulation reduces the risk of stroke while increasing the risk of bleeding. The CHA2DS2-VASc scoring system assesses the risk of stroke, with a score of 2 or greater indicating a need for anticoagulation. The HAS-BLED score estimates the risk of bleeding. Scores of 3 or greater indicate high risk. Warfarin, dabigatran, factor Xa inhibitors (e.g., rivaroxaban, apixaban, edoxaban), and aspirin are options for stroke prevention. Selection of therapy should be individualized based on risks and potential benefits, cost, and patient preference. Left atrial appendage obliteration is an option for reducing stroke risk. Two implantable devices used to occlude the appendage, the Watchman and the Amplatzer Cardiac Plug, appear to be as effective as warfarin in preventing stroke, but they are invasive. Another percutaneous approach to occlusion, wherein the left atrium is closed off using the Lariat, is also available, but data on its long-term effectiveness and safety are still limited. Surgical treatments for atrial fibrillation are reserved for patients who are undergoing cardiac surgery for other reasons.
Yaroslavsky, Ilya; Bylsma, Lauren M.; Rottenberg, Jonathan; Kovacs, Maria
2013-01-01
We examined whether the combined indices of respiratory sinus arrhythmia at rest (resting RSA) and in response to a sad film (RSA reactivity) predict effective and ineffective responses to reduce sadness (adaptive vs. maladaptive mood repair) in women with histories of juvenile-onset depression (n = 74) and no history of major mental disorders (n = 75). Structural equation models were used to estimate latent resting RSA, depression, and adaptive and maladaptive mood repair and to test the study hypotheses. Results indicated that combinations of resting RSA+RSA reactivity (RSA patterns) predicted maladaptive mood repair, which in turn, mediated the effects of RSA pattern on depression. Further, RSA patterns moderated the depressogenic effects of maladaptive mood repair. RSA patterns were unrelated to adaptive mood repair. Our findings suggest that mood repair is one mechanism through which physiological vulnerabilities adversely affect mental health. PMID:23827087
Yaroslavsky, Ilya; Bylsma, Lauren M; Rottenberg, Jonathan; Kovacs, Maria
2013-10-01
We examined whether the combined indices of respiratory sinus arrhythmia at rest (resting RSA) and in response to a sad film (RSA reactivity) predict effective and ineffective responses to reduce sadness (adaptive vs. maladaptive mood repair) in women with histories of juvenile-onset depression (n=74) and no history of major mental disorders (n=75). Structural equation models were used to estimate latent resting RSA, depression, and adaptive and maladaptive mood repair and to test the study hypotheses. Results indicated that combinations of resting RSA+RSA reactivity (RSA patterns) predicted maladaptive mood repair, which in turn, mediated the effects of RSA pattern on depression. Further, RSA patterns moderated the depressogenic effects of maladaptive mood repair. RSA patterns were unrelated to adaptive mood repair. Our findings suggest that mood repair is one mechanism through which physiological vulnerabilities adversely affect mental health. Copyright © 2013 Elsevier B.V. All rights reserved.
Abar, Beau; Sheinkopf, Stephen; Lester, Barry; Lagasse, Linda; Seifer, Ronald; Shankaran, Seetha; Bada-Ellzey, Henrietta; Bauer, Charles; Whitaker, Toni; Hinckley, Matt; Hammond, Jane; Higgins, Rosemary
2014-01-01
We employed latent growth curve analysis to examine trajectories of respiratory sinus arrhythmia (RSA) from 3 to 6 years among children with varying levels of prenatal substance exposure and early adversity. Data were drawn from a prospective longitudinal study of prenatal substance exposure that included 1,121 participants. Baseline RSA and RSA reactivity to an attention-demanding task were assessed at 3, 4, 5, and 6 years. Overall, there were significant individual differences in the trajectories of RSA reactivity, but not baseline RSA, across development. Greater levels of prenatal substance exposure, and less exposure to early adversity, were associated with increased RSA reactivity at 3 years, but by 6 years, both were associated with greater RSA reactivity. Prenatal substance exposure had an indirect influence through early adversity on growth in RSA reactivity. Results are in support of and contribute to the framework of allostatic load. PMID:24002807
Hinnant, James Benjamin; El-Sheikh, Mona
2009-11-01
We examined associations between basal respiratory sinus arrhythmia (RSA) in conjunction with RSA regulation with the hypothesis that their interaction would explain unique variability in children's prospective adjustment 2 years later. Participants were 176 children (98 girls; 78 boys) in middle childhood. RSA regulation was assessed through social and problem-solving challenges. Parents reported on children's internalizing and externalizing symptoms. Interactions between RSA baseline and regulation to the social stressor predicted children's later internalizing symptoms. Interactions between RSA baseline and responding to the problem-solving stressor predicted children's externalizing symptoms. The highest levels of internalizing symptoms were predicted for children with both lower basal RSA and higher RSA suppression. The highest levels of externalizing symptoms were predicted for children who demonstrated lower basal RSA in conjunction with RSA augmentation. Findings highlight the importance of the contemporaneous consideration of basal RSA and RSA regulation in the prediction of developmental psychopathology symptomology.
Ardizzi, Martina; Sestito, Mariateresa; Martini, Francesca; Umiltà, Maria Alessandra; Ravera, Roberto; Gallese, Vittorio
2014-01-01
Age-group membership effects on explicit emotional facial expressions recognition have been widely demonstrated. In this study we investigated whether Age-group membership could also affect implicit physiological responses, as facial mimicry and autonomic regulation, to observation of emotional facial expressions. To this aim, facial Electromyography (EMG) and Respiratory Sinus Arrhythmia (RSA) were recorded from teenager and adult participants during the observation of facial expressions performed by teenager and adult models. Results highlighted that teenagers exhibited greater facial EMG responses to peers' facial expressions, whereas adults showed higher RSA-responses to adult facial expressions. The different physiological modalities through which young and adults respond to peers' emotional expressions are likely to reflect two different ways to engage in social interactions with coetaneous. Findings confirmed that age is an important and powerful social feature that modulates interpersonal interactions by influencing low-level physiological responses. PMID:25337916
A Model-Based Cluster Analysis of Maternal Emotion Regulation and Relations to Parenting Behavior.
Shaffer, Anne; Whitehead, Monica; Davis, Molly; Morelen, Diana; Suveg, Cynthia
2017-10-15
In a diverse community sample of mothers (N = 108) and their preschool-aged children (M age = 3.50 years), this study conducted person-oriented analyses of maternal emotion regulation (ER) based on a multimethod assessment incorporating physiological, observational, and self-report indicators. A model-based cluster analysis was applied to five indicators of maternal ER: maternal self-report, observed negative affect in a parent-child interaction, baseline respiratory sinus arrhythmia (RSA), and RSA suppression across two laboratory tasks. Model-based cluster analyses revealed four maternal ER profiles, including a group of mothers with average ER functioning, characterized by socioeconomic advantage and more positive parenting behavior. A dysregulated cluster demonstrated the greatest challenges with parenting and dyadic interactions. Two clusters of intermediate dysregulation were also identified. Implications for assessment and applications to parenting interventions are discussed. © 2017 Family Process Institute.
García-Castro, José Miguel; García-Martín, Antonia; Guirao-Arrabal, Emilio; Carrillo-Alascio, Pedro Luis
2017-07-01
Symptoms of hypopituitarism are usually chronic and nonspecific, but rarely the disease can have acute and life threatening manifestations. We report a 53 years old female with a pituitary adenoma that was admitted to our hospital because of syncope. The electrocardiogram showed sinus bradycardia with a prolonged QT interval. Frequent runs of non-sustained polymorphic ventricular tachycardia were noted on telemetry. The patient had a history of severe acute headaches in the previous days and laboratory tests revealed severe secondary hypothyroidism, adrenal insufficiency and a decrease in pituitary hormones. A magnetic resonance imaging of the head showed changes in the size and contrast enhancement of the adenoma. A diagnosis of hypopituitarism secondary to pituitary apoplexy was made and treatment with hydrocortisone and, subsequently, levothyroxine was started. Hormonal disorders such as hypothyroidism, adrenal insufficiency or hypopituitarism should be considered as unusual causes for reversible cardiomyopathy, long QT syndrome and ventricular arrhythmias.
Shoulberg, Erin K; Sijtsema, Jelle J; Murray-Close, Dianna
2011-09-01
The association between having a reputation for valuing popularity and relational aggression was assessed in a sample of 126 female children and adolescents (mean age = 12.43 years) at a 54-day residential summer camp for girls. Having a reputation for valuing popularity was positively related to relational aggression. This association was moderated by both popularity and physiological reactivity to social exclusion (i.e., respiratory sinus arrhythmia reactivity [RSAR] and heart rate reactivity [HRR]). Popular girls with a reputation for valuing popularity were at greater risk for engaging in relational aggression when they also exhibited blunted reactivity to social exclusion. Conversely, girls who had a reputation for valuing popularity but were not popular (i.e., the "wannabes") were at risk for engaging in relational aggression when they exhibited heightened reactivity to exclusion. Copyright © 2011 Elsevier Inc. All rights reserved.
Wagner, Nicholas J; Hastings, Paul D; Rubin, Kenneth H
2017-11-29
Callous-unemotional (CU) traits are one meaningful risk factor which helps to explain heterogeneity in the emergence of externalizing behavior problems. While the extant literature demonstrates links between early CU traits and later externalizing problems, there is a dearth of research examining for whom early CU traits confer risk. Data from a longitudinal study (n = 108) were used to examine the extent to which parasympathetic functioning moderated links between CU traits in toddlerhood (m age = 24.99 months) and externalizing behavior problems at preschool-age (m age = 51 months). Neither CU traits nor parasympathetic functioning at age 2 directly predicted later externalizing behaviors. However, results show that high levels of CU traits predict elevated externalizing behavior problems, but only for toddlers exhibiting either high baseline respiratory sinus arrhythmia (RSA) or little to no RSA suppression in response to a fear stimulus.
Sanders, Ashley F P; Hobbs, Diana A; Stephenson, David D; Laird, Robert D; Beaton, Elliott A
2017-04-01
Stress and anxiety have a negative impact on working memory systems by competing for executive resources and attention. Broad memory deficits, anxiety, and elevated stress have been reported in individuals with chromosome 22q11.2 deletion syndrome (22q11.2DS). We investigated anxiety and physiological stress reactivity in relation to visuospatial working memory impairments in 20 children with 22q11.2DS and 32 typically developing (TD) children ages 7 to 16. Children with 22q11.2DS demonstrated poorer working memory, reduced post-stress respiratory sinus arrhythmia recovery, and overall increased levels of cortisol in comparison to TD children. Anxiety, but not physiological stress responsivity, mediated the relationship between 22q11.2DS diagnosis and visuospatial working memory impairment. Findings indicate that anxiety exacerbates impaired working memory in children with 22q11.2DS.
Vagal Activity During Physiological Sexual Arousal in Women With and Without Sexual Dysfunction.
Stanton, Amelia M; Pulverman, Carey S; Meston, Cindy M
2017-01-02
Recently, heart rate variability (HRV) level has been found to be a risk factor for female sexual dysfunction. Low HRV was a significant predictor of female sexual arousal dysfunction and overall sexual dysfunction. Building upon this finding, the present study examined whether differences in vagal activity between sexually functional and sexually dysfunctional women may be driving the association between low HRV and female sexual dysfunction. Specifically, respiratory sinus arrhythmia (RSA) was assessed before, during, and after physiological sexual arousal in 84 women, aged 18 to 47, to examine potential differences in vagal activity between sexually functional and sexually dysfunctional women. Significant differences in vagal activity between these two groups were observed (p =.02). These findings provide additional specificity to the recently established relationship between HRV and female sexual function while also proposing a mechanism to target during treatments for sexual dysfunction.
Eliciting affect via immersive virtual reality: a tool for adolescent risk reduction.
Hadley, Wendy; Houck, Christopher D; Barker, David H; Garcia, Abbe Marrs; Spitalnick, Josh S; Curtis, Virginia; Roye, Scott; Brown, Larry K
2014-04-01
A virtual reality environment (VRE) was designed to expose participants to substance use and sexual risk-taking cues to examine the utility of VR in eliciting adolescent physiological arousal. 42 adolescents (55% male) with a mean age of 14.54 years (SD = 1.13) participated. Physiological arousal was examined through heart rate (HR), respiratory sinus arrhythmia (RSA), and self-reported somatic arousal. A within-subject design (neutral VRE, VR party, and neutral VRE) was utilized to examine changes in arousal. The VR party demonstrated an increase in physiological arousal relative to a neutral VRE. Examination of individual segments of the party (e.g., orientation, substance use, and sexual risk) demonstrated that HR was significantly elevated across all segments, whereas only the orientation and sexual risk segments demonstrated significant impact on RSA. This study provides preliminary evidence that VREs can be used to generate physiological arousal in response to substance use and sexual risk cues.
Asbach, S.; Gutleben, K. J.; Dahlem, P.; Brachmann, J.; Nölker, G.
2010-01-01
Myotonic dystrophy is a genetic muscular disease that is frequently associated with cardiac arrhythmias. Bradyarrhythmias, such as sinus bradycardia and atrioventricular block, are more common than tachyarrhythmias. Rarely, previously undiagnosed patients with myotonic dystrophy initially present with a tachyarrhythmia. We describe the case of a 14-year-old boy, who was admitted to the hospital with clinical signs and symptoms of decompensated heart failure and severely reduced left ventricular function. Electrocardiography showed common-type atrial flutter with 2 : 1 conduction resulting in a heart rate of 160 bpm. Initiation of medical therapy for heart failure as well as electrical cardioversion led to a marked clinical improvement. Catheter ablation of atrial flutter was performed to prevent future cardiac decompensations and to prevent development of tachymyopathy. Left ventricular function normalized during followup. Genetic analysis confirmed the clinical suspicion of myotonic dystrophy as known in other family members in this case. PMID:20871860
Macaque Cardiac Physiology Is Sensitive to the Valence of Passively Viewed Sensory Stimuli
Bliss-Moreau, Eliza; Machado, Christopher J.; Amaral, David G.
2013-01-01
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. PMID:23940712
Davis, Molly; Thomassin, Kristel; Bilms, Joanie; Suveg, Cynthia; Shaffer, Anne; Beach, Steven R. H.
2017-01-01
This study examined three potential moderators of the relations between maternal parenting stress and preschoolers’ adjustment problems: a genetic polymorphism - the short allele of the serotonin transporter (5-HTTLPR, ss/sl allele) gene, a physiological indicator - children’s baseline respiratory sinus arrhythmia (RSA), and a behavioral indicator - mothers’ reports of children’s negative emotionality. A total of 108 mothers (Mage = 30.68 years, SDage = 6.06) reported on their parenting stress as well as their preschoolers’ (Mage = 3.50 years, SDage = .51, 61% boys) negative emotionality and internalizing, externalizing, and sleep problems. Results indicated that the genetic sensitivity variable functioned according to a differential susceptibility model; however, the results involving physiological and behavioral sensitivity factors were most consistent with a diathesis-stress framework. Implications for prevention and intervention efforts to counter the effects of parenting stress are discussed. PMID:28295263
Schoenmaker, Christie; Huffmeijer, Renske; van IJzendoorn, Marinus H; Bakermans-Kranenburg, Marian J; van den Dries, Linda; Linting, Mariëlle; van der Voort, Anja; Juffer, Femmie
2015-02-01
The associations between attachment representations of adopted young adults and their experiential and physiological arousal to infant crying were examined. Attachment representations were assessed with the Attachment Script Assessment (ASA), and the young adults listened to infant cries, during which ratings of cry perception were collected and physiological reactivity was measured. Secure adoptees showed a well-integrated response to infant distress: heart-rate increases and respiratory sinus arrhythmia (RSA) withdrawal were coupled with heightened perception of urgency in these individuals. In insecure adoptees RSA withdrawal was absent, and a combination of lowered perceived urgency and heightened sympathetic arousal was found, reflecting a deactivating style of emotional reactivity. Overall, our findings support the idea that internal working models of attachment explain individual differences in the way attachment-related information is processed. Copyright © 2014 Elsevier Inc. All rights reserved.
[High-dose magnesium sulfate in the treatment of aconite poisoning].
Clara, A; Rauch, S; Überbacher, C A; Felgenhauer, N; Drüge, G
2015-05-01
This article reports the case of a 62-year-old male patient who ingested the roots of Monkshood (Aconitum napellus) and white hellebore (Veratrum album) dissolved in alcohol with a suicidal intention and suffered cardiotoxic and neurotoxic symptoms. After contacting the Poison Information Centre ventricular arrhythmia was treated with high-dose magnesium sulphate as the only antiarrhythmic agent and subsequently a stable sinus rhythm could be established after approximately 3 h. Aconitum napellus is considered the most poisonous plant in Europe and it is found in gardens, the Alps and the Highlands. Poisoning is mainly caused by the alkaloid aconite that leads to persistent opening and activation of voltage-dependent sodium channels resulting in severe cardiac and neurological toxicity. As no specific antidote is known so far, poisoning is associated with a high mortality. The therapy with high-dose magnesium sulphate is based on in vitro and animal experiments as well as limited clinical case reports.
The tell-tale heart: physiological reactivity during resolution of ambiguity in youth anxiety.
Rozenman, Michelle; Vreeland, Allison; Iglesias, Marisela; Mendez, Melissa; Piacentini, John
2018-03-01
In the past decade, cognitive biases and physiological arousal have each been proposed as mechanisms through which paediatric anxiety develops and is maintained over time. Preliminary studies have found associations between anxious interpretations of ambiguity, physiological arousal, and avoidance, supporting theories that link cognition, psychophysiology, and behaviour. However, little is known about the relationship between youths' resolutions of ambiguity and physiological arousal during acute stress. Such information may have important clinical implications for use of verbal self-regulation strategies and cognitive restructuring during treatments for paediatric anxiety. In this brief report, we present findings suggesting that anxious, but not typically developing, youth select avoidant goals via non-threatening resolution of ambiguity during a stressor, and that this resolution of ambiguity is accompanied by physiological reactivity (heart rate, heart rate variability, and respiratory sinus arrhythmia). We propose future empirical research on the interplay between interpretation bias, psychophysiology, and child anxiety, as well as clinical implications.
Graziano, Paulo A.; Bagner, Daniel M.; Sheinkopf, Stephen J.; Vohr, Betty R.; Lester, Barry M.
2012-01-01
The current study examined whether changes in maternal behaviors following an evidence-based treatment—Parent Child Interaction Therapy (PCIT)—was associated with improvements in cardiac vagal regulation in young children born premature. Participants included 28 young children (mean age = 37.79 months) that were born premature and presented with elevated externalizing behavior problems. To assess cardiac vagal regulation, resting measures of respiratory sinus arrhythmia (RSA) and RSA change (withdrawal or suppression) to a clean-up task were derived pre and post-treatment. Results indicated that an increase in behaviors mothers are taught to use during treatment (i.e., do skills—praise, reflection, and behavioral descriptions) were associated with an improvement in children’s post-treatment RSA suppression levels. The current study illustrates the important role of caregiver behavior in promoting physiological regulation in children born premature. PMID:22721742
Carrara, Marta; Carozzi, Luca; Moss, Travis J; de Pasquale, Marco; Cerutti, Sergio; Lake, Douglas E; Moorman, J Randall; Ferrario, Manuela
2015-01-01
Identification of atrial fibrillation (AF) is a clinical imperative. Heartbeat interval time series are increasingly available from personal monitors, allowing new opportunity for AF diagnosis. Previously, we devised numerical algorithms for identification of normal sinus rhythm (NSR), AF, and SR with frequent ectopy using dynamical measures of heart rate. Here, we wished to validate them in the canonical MIT-BIH ECG databases. We tested algorithms on the NSR, AF and arrhythmia databases. When the databases were combined, the positive predictive value of the new algorithms exceeded 95% for NSR and AF, and was 40% for SR with ectopy. Further, dynamical measures did not distinguish atrial from ventricular ectopy. Inspection of individual 24hour records showed good correlation of observed and predicted rhythms. Heart rate dynamical measures are effective ingredients in numerical algorithms to classify cardiac rhythm from the heartbeat intervals time series alone. Copyright © 2015 Elsevier Inc. All rights reserved.
Clark, Christine M; Frye, Charles G; Wardle, Margaret C; Norman, Greg J; de Wit, Harriet
2015-03-01
MDMA is a stimulant with unique "prosocial" effects, the physiological and pharmacological mechanisms of which are unknown. Here, we examine the relationship of measures of parasympathetic and sympathetic nervous system activity to the prosocial effects of MDMA. Parasympathetic activity was measured using respiratory sinus arrhythmia (RSA) and sympathetic activity using pre-ejection period (PEP). Over three sessions, 33 healthy volunteers received placebo, 0.75 mg/kg, and 1.5 mg/kg MDMA under counterbalanced, double-blind conditions, while we measured subjective feelings, RSA, and PEP. RSA and PEP data were available for 26 and 21 participants, respectively. MDMA increased prosocial and stimulated feelings, decreased RSA, and decreased PEP. At 1.5 mg/kg, subjective prosocial effects correlated with stimulated feelings and PEP, but not RSA. This suggests sympathetic, rather than parasympathetic, effects relate to the prosocial effects of MDMA. © 2014 Society for Psychophysiological Research.
ICD defibrillation failure solved in an unusual fashion.
Oliveira, Ricardo Gil; Madeira, Francisco; Ferreira, Ana Rita; Antunes, Susana; Morais, Carlos; Gil, Victor
2010-04-01
An implantable cardioverter defibrillator (ICD) is designed to sense life-threatening ventricular arrhythmias and terminate them, either by rapid pacing or by delivering an electrical shock. Nowadays it is a proven therapy for both primary and secondary prevention of sudden cardiac death. The typical configuration of an ICD consists of a right ventricular sensing/defibrillator lead with two coils (one distal, located in the right ventricle, and one proximal, located at the superior vena cava-right atrium junction) and an active can, the so-called "ventricular triad". Although effective in the vast majority of patients, it could be argued that this is not the most rational arrangement in electrical terms, since the main shock vector is anteriorly displaced in relation to the greater portion of the left ventricular mass. We describe a case of an ICD defibrillation failure that was solved by placing an additional defibrillator lead in a tributary of the coronary sinus.
Hasselmo, Karen; Sbarra, David A.; O'Connor, Mary-Frances; Moreno, Francisco A.
2015-01-01
Marital separation is linked to negative mental and physical health; however, the strength of this link may vary across people. This study examined changes in respiratory sinus arrhythmia (RSA), used to assess cardiac vagal control, in recently separated adults (N = 79; M time since separation = 3.5 months). When reflecting over the separation, self-reported psychological distress following the separation interacted with a polymorphism in the serotonin transporter gene (5-HTTLPR) and a relevant single nucleotide polymorphism (SNP), rs25531, to predict RSA. Among people reporting emotional difficulties after the separation, those who were homozygous for the short allele had lower RSA levels while reflecting on their relationship than other genotypes. The findings, although limited by the relatively small sample size, are discussed in terms of how higher-sensitivity genotypes may interact with psychological responses to stress to alter physiology. PMID:25630596
Kristjánsdóttir, Ingibjörg; Reimarsdóttir, Guđrun; Arnar, Davíđ O
2012-09-01
Syncope is a common complaint and determining the underlying cause can be difficult despite extensive evaluation. The purpose of this study was to evaluate the usefulness of an implantable loop recorder for patients with unexplained syncope and palpitations. This was a retrospective analysis of 18 patients, five of whom still have the device implanted. All patients had undergone extensive evaluation for their symptoms before getting the loop recorder implanted and this was therefore a highly select group. Of the thirteen patients where use of the device was completed, the mean age was 65±20 years. The loop recorder was in use for a mean time of 20±13 months. Unexplained syncope, eleven of thirteen, was the most common indication. The other two received the loop recorder for unexplained palpitations. Four patients had sick sinus syndrome during monitoring, three had supraventricular tachycardia and one had ventricular tachycardia. Further three had typical symptoms but no arrhythmia was recorded and excluding that as a cause. Two patients had no symptoms the entire time they had the loop recorder. Of the five patients still with the device three had syncope as the indication for monitoring and two have the device as a means of evaluating the results of treatment for arrhythmia. This study on our initial experience with implantable loop recorders shows that these devices can be useful in the investigation of the causes of syncope and palpitations.
Negreva, Mariya N; Penev, Atanas P; Georgiev, Svetoslav Zh; Aleksandrova, Albena A
2014-01-01
Researchers have a particularly strong interest in the mechanisms implicated in the clinical manifestation of atrial fibrillation. To examine dynamically the activity of the antioxidant enzymes, superoxide dismutase and catalase in patients with paroxysmal atrial fibrillation (duration < 48 hours). The studied parameters were examined in the erythrocytes of 51 patients (59.84 +/- 1.60, 26 men) immediately after their hospitalization, at 24 hours and 28 days after restoration of sinus rhythm. 52 controls (59.50 +/- 1.46, 26 men) were also included, none of which had a history of arrhythmia. Propafenone was used to manage the rhythm abnormality. The enzyme activity was determined by a spectrophotometric method. The average duration of atrial fibrillation episodes until the time of hospitalization was 8.14 hours (from 2 to 24 hours). During patient hospitalization the activity of superoxide dismutase and catalase was considerably higher compared to that of the controls (8.46 +/- 0.26 vs 5.81 +/- 0.14 U/mg Hb; 7.36 +/- 0.25 vs 4.76 +/- 0.12 E240/min/mg Hb; P < 0.001). This difference was maintained 24 hours after the rhythm regularization (7.19 +/- 0.25 vs 5.81 +/- 0.14 U/mg Hb, p < 0.001; 5.30 +/- 0.21 vs 4.76 +/- 0.12 E240/min/mg Hb, p < 0.05). Twenty-eight days after the restoration of sinus rhythm, the activity of catalase remained increased (5.11 +/- 0.08 vs 4.76 +/- 0.12 E240/min/mg Hb, p < 0.05). The paroxysmal atrial fibrillation in our study was characterized with significantly increased activity of superoxide dismutase and catalase even in the early hours of clinical manifestation of the disorder, which then slowly decreased with the restoration of sinus rhythm. Therefore, we can conclude that changes in oxidative status are closely related to the disease and are probably a part of the intimate mechanisms related to its initiation and clinical course.
Dronedarone: a promising alternative for the management of atrial fibrillation.
Yalta, Kenan; Turgut, Okan Onur; Yilmaz, Mehmet Birhan; Yilmaz, Ahmet; Tandogan, Izzet
2009-10-01
Atrial fibrillation (AF) is the most frequently encountered chronic arrhythmia associated with significant morbidity. It is generally encountered in the elderly, and will presumably become more prevalent in the future due to the increasing proportion of the elderly in the population. Major studies on AF have demonstrated no significant difference between rhythm and rate control in terms of mortality. However, young population with new-onset or lone AF, or patients in whom the maintenance of sinus rhythm is a must (due to recurrent thromboembolic events etc.) still gives rise to significant concerns related to the obligatory long-term prophylaxis. The long-term administration of the currently available conventional agents (amiodarone, dofetilide, sotalol, propafenone,flecainide etc.) is considered as a 'double edged sword' due to the presence of life-threatening adverse effects including pro-arrhythmia and organ toxicity associated with these agents. Several molecules are being developed for the management of AF. However, only a few novel agents confer promising results with respect to safety and efficacy issues in the major studies. Dronedarone is an amiodarone analogue without iodine moiety in its structure, and is similar to amiodarone with regard to its structural and electrophysiological properties. Dronedarone is largely denuded of the potentially life-threatening adverse effects of anti-arrhythmics. Major clinical studies have demonstrated both rhythm and rate-controlling efficacy of dronedarone compared to placebo without any serious adverse effects in patients with AF. However, the ANDROMEDA trial, a large scale study including patients hospitalized for symptomatic congestive heart failure (with severely depressed left ventricular systolic functions) was prematurely terminated due to the increased mortality in the dronedarone arm compared to placebo indicating a lack of safety in this group of patients. Conversely, the recently published ATHENA study (including more than 4,600 high risk patients, but excluding those with severe heart failure) demonstrated a significant reduction in cardiovascular hospitalizations and cardiovascular mortality with dronedarone compared to placebo. In contrast, the DIONYSOS study, comparing dronedarone with amiodarone, demonstrated better safety, but lower efficacy of dronedarone for the maintenance of sinus rhythm in patients with AF. Further clinical trials (including head to head comparison with other conventional anti-arrhythmics) are still required to determine the place of dronedarone in the management of AF. The present review focuses on basic and clinical aspects of dronedarone, a novel agent for the management of AF.
Impaired endothelial function in lone atrial fibrillation.
Polovina, Marija; Potpara, Tatjana; Giga, Vojislav; Stepanović, Jelena; Ostojić, Miodrag
2013-10-01
Impaired endothelial function has been previously documented in patients with atrial fibrillation (AF) and underlying comorbidities or older patients with idiopathic AF. The aim of this study was to evaluate systemic endothelial function in younger AF patients (less than < 60 years old) with lone AF (that is, without associated cardiopulmonary comorbidities, including arterial hypertension), by comparing brachial artery flow-mediated dilation (FMD) in lone AF patients with FMD of healthy subjects in sinus rhythm. Two groups of participants were prospectively enrolled. The first group comprised of 38 AF patients (the mean age 45 +/- 11 years, 68% male) with persistent (> 7 days) lone AF. The second group comprised of 28 healthy controls in sinus rhythm (the mean age 43 +/- 13, 53% male), matched by age, gender and atherosclerotic risk factors. All the participants underwent physical examination, laboratory analysis [including determination of C-reactive protein (CRP)], standard echocardiography and exercise-stress testing. Brachial artery FMD and endothelium independent dilation (NMD) were assessed with a high-resolution ultrasound probe and arterial diameters taken from 5 consecutive cardiac cycles were averaged for each measurement to accommodate to beat-to-beat flow variations in AF. There were no differences between the 2 groups regarding age, gender and most clinical, laboratory and echocardiographic characteristics (all p > 0.05), apart from the increased heart rate (p = 0.018), body mass index (p = 0.027), CRP levels (p = 0.007) and left atrial anteroposterior dimension (p < 0.001) in AF patients. FMD of AF patients [median value 5.0%, interquartile range (IQR) 2.87%-7.50%] was significantly lower (p < 0.001) than FMD of healthy controls (median value 8.85%, IQR 5.80%-12.50%), whereas there were no differences in median NMD values (p > 0.05). In the multivariate analysis, the independent FMD determinants in our study population were the presence of AF, smoking and total cholesterol levels (all p < 0.001). In patients with AF, the strongest independent FMD determinant was arrhythmia duration (p < 0.001), followed by smoking (p = 0.013) and total cholesterol levels (p = 0.045). Our findings confirm that sustained AF is associated with systemic endothelial dysfunction even in relatively young patients with no cardiovascular disorders or risk factors. AF is an independent contributor to lower FMD and a prolonged arrhythmia duration may confer the risk for more profound endothelial damage.
In vivo dose measurement using TLDs and MOSFET dosimeters for cardiac radiosurgery.
Gardner, Edward A; Sumanaweera, Thilaka S; Blanck, Oliver; Iwamura, Alyson K; Steel, James P; Dieterich, Sonja; Maguire, Patrick
2012-05-10
In vivo measurements were made of the dose delivered to animal models in an effort to develop a method for treating cardiac arrhythmia using radiation. This treatment would replace RF energy (currently used to create cardiac scar) with ionizing radiation. In the current study, the pulmonary vein ostia of animal models were irradiated with 6 MV X-rays in order to produce a scar that would block aberrant signals characteristic of atrial fibrillation. The CyberKnife radiosurgery system was used to deliver planned treatments of 20-35 Gy in a single fraction to four animals. The Synchrony system was used to track respiratory motion of the heart, while the contractile motion of the heart was untracked. The dose was measured on the epicardial surface near the right pulmonary vein and on the esophagus using surgically implanted TLD dosimeters, or in the coronary sinus using a MOSFET dosimeter placed using a catheter. The doses measured on the epicardium with TLDs averaged 5% less than predicted for those locations, while doses measured in the coronary sinus with the MOSFET sensor nearest the target averaged 6% less than the predicted dose. The measurements on the esophagus averaged 25% less than predicted. These results provide an indication of the accuracy with which the treatment planning methods accounted for the motion of the target, with its respiratory and cardiac components. This is the first report on the accuracy of CyberKnife dose delivery to cardiac targets.
Ziacchi, Matteo; Palmisano, Pietro; Biffi, Mauro; Ricci, Renato P; Landolina, Maurizio; Zoni-Berisso, Massimo; Occhetta, Eraldo; Maglia, Giampiero; Botto, Gianluca; Padeletti, Luigi; Boriani, Giuseppe
2018-04-01
: Modern pacemakers have an increasing number of programable parameters and specific algorithms designed to optimize pacing therapy in relation to the individual characteristics of patients. When choosing the most appropriate pacemaker type and programing, the following variables must be taken into account: the type of bradyarrhythmia at the time of pacemaker implantation; the cardiac chamber requiring pacing, and the percentage of pacing actually needed to correct the rhythm disorder; the possible association of multiple rhythm disturbances and conduction diseases; the evolution of conduction disorders during follow-up. The goals of device programing are to preserve or restore the heart rate response to metabolic and hemodynamic demands; to maintain physiological conduction; to maximize device longevity; to detect, prevent, and treat atrial arrhythmia. In patients with sinus node disease, the optimal pacing mode is DDDR. Based on all the available evidence, in this setting, we consider appropriate the activation of the following algorithms: rate responsive function in patients with chronotropic incompetence; algorithms to maximize intrinsic atrioventricular conduction in the absence of atrioventricular blocks; mode-switch algorithms; algorithms for autoadaptive management of the atrial pacing output; algorithms for the prevention and treatment of atrial tachyarrhythmias in the subgroup of patients with atrial tachyarrhythmias/atrial fibrillation. The purpose of this two-part consensus document is to provide specific suggestions (based on an extensive literature review) on appropriate pacemaker setting in relation to patients' clinical features.
Dronedarone: current evidence for its safety and efficacy in the management of atrial fibrillation.
Schweizer, Patrick A; Becker, Rüdiger; Katus, Hugo A; Thomas, Dierk
2011-01-06
Atrial fibrillation (AF) is the most common sustained arrhythmia. Management of AF includes rate control, rhythm control if necessary, prevention of thromboembolic events, and treatment of the underlying disease. Rate control is usually achieved by pharmacological suppression of calcium currents or by applying β-blockers or digitalis compounds. In contrast, the number of compounds available for rhythm control is still limited. Class Ic agents increase mortality in patients with structural heart disease, and amiodarone harbors an extensive side effect profile despite its efficacy in maintaining sinus rhythm. Furthermore, rhythm control by these compounds has not been shown to reduce patient mortality. Dronedarone is a new anti-arrhythmic drug that has been developed to provide rhythm and rate control in AF patients with fewer side effects compared with amiodarone. This review primarily focuses on clinical trials evaluating efficacy and safety of the novel drug. Conclusions from these studies are critically reviewed, and recommendations for clinical practice are discussed. Dronedarone significantly reduced the incidence of hospitalization due to cardiovascular events or death in high-risk patients with atrial fibrillation (ATHENA trial). However, dronedarone was less efficient than amiodarone in maintaining normal sinus rhythm (DIONYSOS trial) and is contraindicated in severe or deteriorating heart failure (ANDROMEDA trial). In summary, dronedarone represents a valuable addition to the limited spectrum of antiarrhythmic drugs and is currently recommended in patients with paroxysmal and persistent AF to achieve rate and rhythm control, excluding cases of severe or unstable congestive heart failure.
Konofagou, Elisa E.; Provost, Jean
2014-01-01
Cardiovascular diseases rank as America’s primary killer, claiming the lives of over 41% of more than 2.4 million Americans. One of the main reasons for this high death toll is the severe lack of effective imaging techniques for screening, early detection and localization of an abnormality detected on the electrocardiogram (ECG). The two most widely used imaging techniques in the clinic are CT angiography and echocardiography with limitations in speed of application and reliability, respectively. It has been established that the mechanical and electrical properties of the myocardium change dramatically as a result of ischemia, infarction or arrhythmia; both at their onset and after survival. Despite these findings, no imaging technique currently exists that is routinely used in the clinic and can provide reliable, non-invasive, quantitative mapping of the regional, mechanical and electrical function of the myocardium. Electromechanical Wave Imaging (EWI) is an ultrasound-based technique that utilizes the electromechanical coupling and its associated resulting strain to infer to the underlying electrical function of the myocardium. The methodology of EWI is first described and its fundamental performance is presented. Subsequent in vivo canine and human applications are provided that demonstrate the applicability of Electromechanical Wave Imaging in differentiating between sinus rhythm and induced pacing schemes as well as mapping arrhythmias. Preliminary validation with catheter mapping is also provided and transthoracic electromechanical mapping in all four chambers of the human heart is also presented demonstrating the potential of this novel methodology to noninvasively infer to both the normal and pathological electrical conduction of the heart. PMID:22284425
Navara, Rachita; Leef, George; Shenasa, Fatemah; Kowalewski, Christopher; Rogers, Albert J; Meckler, Gabriela; Zaman, Junaid A B; Baykaner, Tina; Park, Shirley; Turakhia, Mintu P; Zei, Paul; Viswanathan, Mohan; Wang, Paul J; Narayan, Sanjiv M
2018-01-29
To investigate mechanisms by which atrial fibrillation (AF) may terminate during ablation near the pulmonary veins before the veins are isolated (PVI). It remains unstudied how AF may terminate during ablation before PVs are isolated, or how patients with PV reconnection can be arrhythmia-free. We studied patients in whom PV antral ablation terminated AF before PVI, using two independent mapping methods. We studied patients with AF referred for ablation, in whom biatrial contact basket electrograms were studied by both an activation/phase mapping method and by a second validated mapping method reported not to create false rotational activity. In 22 patients (age 60.1 ± 10.4, 36% persistent AF), ablation at sites near the PVs terminated AF (77% to sinus rhythm) prior to PVI. AF propagation revealed rotational (n = 20) and focal (n = 2) patterns at sites of termination by mapping method 1 and method 2. Both methods showed organized sites that were spatially concordant (P < 0.001) with similar stability (P < 0.001). Vagal slowing was not observed at sites of AF termination. PV antral regions where ablation terminated AF before PVI exhibited rotational and focal activation by two independent mapping methods. These data provide an alternative mechanism for the success of PVI, and may explain AF termination before PVI or lack of arrhythmias despite PV reconnection. Mapping such sites may enable targeted PV lesion sets and improved freedom from AF. © 2018 Wiley Periodicals, Inc.
Ben Jehuda, Ronen; Eisen, Binyamin; Shemer, Yuval; Mekies, Lucy N; Szantai, Agnes; Reiter, Irina; Cui, Huanhuan; Guan, Kaomei; Haron-Khun, Shiraz; Freimark, Dov; Sperling, Silke R; Gherghiceanu, Mihaela; Arad, Michael; Binah, Ofer
2018-02-01
Mutations in the PRKAG2 gene encoding the γ-subunit of adenosine monophosphate kinase (AMPK) cause hypertrophic cardiomyopathy (HCM) and familial Wolff-Parkinson-White (WPW) syndrome. Patients carrying the R302Q mutation in PRKAG2 present with sinus bradycardia, escape rhythms, ventricular preexcitation, supraventricular tachycardia, and atrioventricular block. This mutation affects AMPK activity and increases glycogen storage in cardiomyocytes. The link between glycogen storage, WPW syndrome, HCM, and arrhythmias remains unknown. The purpose of this study was to investigate the pathological changes caused by the PRKAG2 mutation. We tested the hypothesis that patient's induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) display clinical aspects of the disease. Using clustered regularly interspaced short palindromic repeats (CRISPR) technology, we corrected the mutation and then generated isogenic iPSC-CMs. Action potentials were recorded from spontaneously firing and paced cardiomyocytes using the patch clamp technique. Using a microelectrode array setup, we recorded electrograms from iPSC-CMs clusters. Transmission electron microscopy was used to detect ultrastructural abnormalities in the mutated iPSC-CMs. PRKAG2-mutated iPSC-CMs exhibited abnormal firing patterns, delayed afterdepolarizations, triggered arrhythmias, and augmented beat rate variability. Importantly, CRISPR correction eliminated the electrophysiological abnormalities, the augmented glycogen, storage, and cardiomyocyte hypertrophy. PRKAG2-mutated iPSC-CMs displayed functional and structural abnormalities, which were abolished by correcting the mutation in the patient's iPSCs using CRISPR technology. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Portella, Renata Boschi; Pedrosa, Roberto Coury; Coeli, Claudia Medina; Buescu, Alexandru; Vaisman, Mario
2007-08-01
Subclinical hyperthyroidism (SH) has been associated with exercise intolerance, changes in cardiac morphology, atrial arrhythmias and sympathovagal imbalance. The aim of this study was to evaluate the vagal reserve and modulation by a sympathetic stimulus in nonelderly patients with SH without cardiovascular problems. We carried out a cross-sectional study, comparing data of the heart rate variability (HRV) of SH patients and healthy controls at rest and after vagal and sympathetic stimulation. We studied 16 female patients with at least 6 months of SH and 16 healthy female controls with the same median age (40 vs. 34.5 years). We used the tilt test, with electrocardiographic record at rest, during the respiratory sinus arrhythmia (RSA) manoeuvre and after tilting, in order to analyse HRV in the frequency domain (%high frequency (HF) and low/high frequency ratio (LF/HF) using Biopotentials Captation System software. The median TSH level was 0.03 mU/l in patients and 1.37 mUI/l in controls. The median free T4 was 1.37 ng/dl in patients and 1.20 ng/dl in controls. Patients demonstrated a significantly smaller difference between %HF during the RSA and %HF at rest than controls (median -7.5 vs. 36.6, P < 0.001). There was a lower difference between LF/HF ratio after tilting and LF/HF ratio at rest in patients than in controls (1.5 vs. 5.3, P = 0.005). Subclinical hyperthyroidism affects cardiovascular autonomic balance in otherwise apparently healthy nonelderly females by blunting vagal responses.
Manolis, A G; Katsivas, A G; Vassilopoulos, C; Koutsogeorgis, D; Louvros, N E
2002-04-01
Interatrial septum (IAS) pacing seems efficient in synchronizing atrial depolarization in patients (pts) with delayed inter-atrial conduction, but its clinical role in preventing atrial tachyarrhythmias is still debated. This study was conducted in order to evaluate the clinical efficacy of IAS pacing guided by pace mapping of the IAS, as an alternative treatment modality in pts with drug refractory paroxysmal atrial fibrillation (PAF). We evaluated 29 pts (13 male, 16 female, 60 +/- 11 years), with drug refractory PAF, normal sinus node function and prolonged inter-atrial conduction time (P wave 142 +/- 10 ms). Multipolar catheters were inserted and the electrograms from the high right atrium (HRA) and proximal, middle and distal coronary sinus (CS) were recorded. The IAS was paced from multiple sites. The site of IAS where the timing between HRA and distal CS was <20 ms was considered the most suitable for synchronizing the atria. This site was found to be superior to the CS os. near the fossa ovalis in all pts. An active fixation atrial lead was positioned at this site and a standard lead was placed in the right ventricle. During IAS pacing, the P wave duration decreased significantly to 107 +/- 15 ms (P<0.001). At implant, the atrial sensing was 2.3 +/- 0.7 mV, the atrial pacing threshold was 0.95 +/- 0.15 V (0.5 ms) and the impedance was 760 +/- 80 Ohm. We evaluated the pts during four periods of 3 months duration each. The first period (control) was before pacemaker implantation, while the pts were under antiarrhythmic treatment. During the subsequent two periods, we evaluated the clinical efficacy of IAS pacing to prevent PAF recurrences, in AAT (75 bpm) and AAIR (75-140 bpm) mode, with random selection of the order and after discontinuation of antiarrhythmic treatment. During the fourth period, the same AAIR mode was assessed, but antiarrhythmic drugs were also administered. We compared the arrhythmia free interval among the four periods. The proportion of atrial paced beats in AAIR pacing mode plus antiarrhythmics was significantly higher compared with the drug-free period in AAIR mode (57 +/- 9% and 49 +/- 9% respectively, P=0017) and with AAT pacing mode (44 +/- 10%,(, P<0.001). In AAT mode, the arrhythmia free interval was 24.2 +/- 5.1 days, while it was 26.2 +/- 5.7 days in AAIR mode. These intervals did not differ significantly from the pre-implantation period (24.1 +/- 6.3 days). The arrhythmia free interval in AAIR pacing in combination with antiarrhythmic drug therapy was 38.7 +/- 8.1 days and this was significantly longer than the previous periods (P<0.05). Atrial septal pacing in combination with antiarrhythmic drug therapy reduced the incidence of PAF in pts with prolonged inter-atrial conduction times. Pace mapping of the IAS is an attractive technique to assess the shortest atrial activation time between HRA and distal CS. Whether placement of the atrial lead based on the shortest HRA--distal CS time is the best place in the IAS to prevent PAF still remains to be proven.
Jekova, Irena; Krasteva, Vessela; Ménétré, Sarah; Stoyanov, Todor; Christov, Ivaylo; Fleischhackl, Roman; Schmid, Johann-Jakob; Didon, Jean-Philippe
2009-07-01
This paper presents a bench study on a commercial automated external defibrillator (AED). The objective was to evaluate the performance of the defibrillation advisory system and its robustness against electromagnetic interferences (EMI) with central frequencies of 16.7, 50 and 60 Hz. The shock advisory system uses two 50 and 60 Hz band-pass filters, an adaptive filter to identify and suppress 16.7 Hz interference, and a software technique for arrhythmia analysis based on morphology and frequency ECG parameters. The testing process includes noise-free ECG strips from the internationally recognized MIT-VFDB ECG database that were superimposed with simulated EMI artifacts and supplied to the shock advisory system embedded in a real AED. Measurements under special consideration of the allowed variation of EMI frequency (15.7-17.4, 47-52, 58-62 Hz) and amplitude (1 and 8 mV) were performed to optimize external validity. The accuracy was reported using the American Heart Association (AHA) recommendations for arrhythmia analysis performance. In the case of artifact-free signals, the AHA performance goals were exceeded for both sensitivity and specificity: 99% for ventricular fibrillation (VF), 98% for rapid ventricular tachycardia (VT), 90% for slow VT, 100% for normal sinus rhythm, 100% for asystole and 99% for other non-shockable rhythms. In the presence of EMI, the specificity for some non-shockable rhythms (NSR, N) may be affected in some specific cases of a low signal-to-noise ratio and extreme frequencies, leading to a drop in the specificity with no more than 7% point. The specificity for asystole and the sensitivity for VF and rapid VT in the presence of any kind of 16.7, 50 or 60 Hz EMI simulated artifact were shown to reach the equivalence of sensitivity required for non-noisy signals. In conclusion, we proved that the shock advisory system working in a real AED operates accurately according to the AHA recommendations without artifacts and in the presence of EMI. The results may be affected for specificity in the case of a low signal-to-noise ratio or in some extreme frequency setting.
Jularic, Mario; Akbulak, Ruken Özge; Schäffer, Benjamin; Moser, Julia; Nuehrich, Jana; Meyer, Christian; Eickholt, Christian; Willems, Stephan; Hoffmann, Boris A
2018-03-01
During ablation in the vicinity of the coronary arteries establishing a safe distance from the catheter tip to the relevant vessels is mandatory and usually assessed by fluoroscopy alone. The aim of the study was to investigate the feasibility of an image integration module (IIM) for continuous monitoring of the distance of the ablation catheter tip to the main coronary arteries during ablation of ventricular arrhythmias (VA) originating in the sinus of valsalva (SOV) and the left ventricular summit part of which can be reached via the great cardiac vein (GCV). Of 129 patients undergoing mapping for outflow tract arrhythmias from June 2014 till October 2015, a total of 39 patients (52.4 ± 18.1 years, 17 female) had a source of origin in the SOV or the left ventricular summit. Radiofrequency (RF) ablation was performed when a distance of at least 5 mm could be demonstrated with IIM. A safe distance in at least one angiographic plane could be demonstrated in all patients with a source of origin in the SOV, whereas this was not possible in 50% of patients with earliest activation in the summit area. However, using the IIM a safe position at an adjacent site within the GCV could be obtained in three of these cases and successful RF ablation performed safely without any complications. Ablation was successful in 100% of patients with an origin in the SOV, whereas VAs originating from the left ventricular summit could be abolished completely in only 60% of cases. Image integration combining electroanatomical mapping and fluoroscopy allows assessment of the safety of a potential ablation site by continuous real-time monitoring of the spatial relations of the catheter tip to the coronary vessels prior to RF application. It aids ablation in anatomically complex regions like the SOV or the ventricular summit providing biplane angiograms merged into the three-dimensional electroanatomical map. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.
Mutation E169K in junctophilin-2 causes atrial fibrillation due to impaired RyR2 stabilization.
Beavers, David L; Wang, Wei; Ather, Sameer; Voigt, Niels; Garbino, Alejandro; Dixit, Sayali S; Landstrom, Andrew P; Li, Na; Wang, Qiongling; Olivotto, Iacopo; Dobrev, Dobromir; Ackerman, Michael J; Wehrens, Xander H T
2013-11-19
This study sought to study the role of junctophilin-2 (JPH2) in atrial fibrillation (AF). JPH2 is believed to have an important role in sarcoplasmic reticulum (SR) Ca(2+) handling and modulation of ryanodine receptor Ca(2+) channels (RyR2). Whereas defective RyR2-mediated Ca(2+) release contributes to the pathogenesis of AF, nothing is known about the potential role of JPH2 in atrial arrhythmias. Screening 203 unrelated hypertrophic cardiomyopathy patients uncovered a novel JPH2 missense mutation (E169K) in 2 patients with juvenile-onset paroxysmal AF (pAF). Pseudoknock-in (PKI) mouse models were generated to determine the molecular defects underlying the development of AF caused by this JPH2 mutation. PKI mice expressing E169K mutant JPH2 exhibited a higher incidence of inducible AF than wild type (WT)-PKI mice, whereas A399S-PKI mice expressing a hypertrophic cardiomyopathy-linked JPH2 mutation not associated with atrial arrhythmias were not significantly different from WT-PKI. E169K-PKI but not A399A-PKI atrial cardiomyocytes showed an increased incidence of abnormal SR Ca(2+) release events. These changes were attributed to reduced binding of E169K-JPH2 to RyR2. Atrial JPH2 levels in WT-JPH2 transgenic, nontransgenic, and JPH2 knockdown mice correlated negatively with the incidence of pacing-induced AF. Ca(2+) spark frequency in atrial myocytes and the open probability of single RyR2 channels from JPH2 knockdown mice was significantly reduced by a small JPH2-mimicking oligopeptide. Moreover, patients with pAF had reduced atrial JPH2 levels per RyR2 channel compared to sinus rhythm patients and an increased frequency of spontaneous Ca(2+) release events. Our data suggest a novel mechanism by which reduced JPH2-mediated stabilization of RyR2 due to loss-of-function mutation or reduced JPH2/RyR2 ratios can promote SR Ca(2+) leak and atrial arrhythmias, representing a potential novel therapeutic target for AF. Copyright © 2013. Published by Elsevier Inc.
Mutation E169K in junctophilin-2 causes atrial fibrillation due to impaired RyR2 stabilization
Voigt, Niels; Garbino, Alejandro; Dixit, Sayali S.; Landstrom, Andrew P.; Li, Na; Wang, Qiongling; Olivotto, Iacopo; Dobrev, Dobromir; Ackerman, Michael J.; Wehrens, Xander H.T.
2013-01-01
Objectives To study the role of junctophilin 2 (JPH2) in atrial fibrillation (AF). Background JPH2 is believed to have an important role in sarcoplasmic reticulum (SR) Ca2+ handling and modulation of ryanodine receptor Ca2+ channels (RyR2). Whereas defective RyR2-mediated Ca2+ release contributes to the pathogenesis of AF, nothing is known about the potential role of JPH2 in atrial arrhythmias. Methods Screening 203 unrelated hypertrophic cardiomyopathy patients uncovered a novel JPH2 missense mutation (E169K) in 2 patients with juvenile-onset paroxysmal AF (pAF). Pseudo-knockin (PKI) mouse models were generated to determine the molecular defects underlying the development of AF caused by this JPH2 mutation. Results PKI mice expressing E169K mutant JPH2 exhibited a higher incidence of inducible AF compared with wildtype (WT)-PKI mice, while A399S-PKI mice expressing a HCM-linked JPH2 mutation not associated with atrial arrhythmias were not significantly different from WT-PKI. E169K-PKI but not A399A-PKI atrial cardiomyocytes showed an increased incidence of abnormal SR Ca2+ release events. These changes were attributed to reduced binding of E169KJPH2 to RyR2. Atrial JPH2 levels in WT-JPH2 transgenic, nontransgenic, and JPH2 knockdown mice correlated negatively with the incidence of pacing-induced AF. Ca2+ spark frequency in atrial myocytes and the open probability of single RyR2 channels from JPH2 knockdown mice was significantly reduced by a small JPH2-mimicking oligopeptide. Moreover, patients with pAF had reduced atrial JPH2 levels per RyR2 channel compared to sinus rhythm patients, and an increased frequency of spontaneous Ca2+ release events. Conclusions Our data suggest a novel mechanism by which reduced JPH2-mediated stabilization of RyR2 due to loss-of-function mutation or reduced JPH2:RyR2 ratios can promote SR Ca2+ leak and atrial arrhythmias, representing a potential novel therapeutic target for AF. PMID:23973696
Family enmeshment, adolescent emotional dysregulation, and the moderating role of gender.
Kivisto, Katherine Little; Welsh, Deborah P; Darling, Nancy; Culpepper, Christi L
2015-08-01
Enmeshment plays a key role in many families' dysfunctional interactions and may be especially detrimental for adolescents. Sixty-four adolescents completed ratings of family enmeshment, perceived distress tolerance, an interpersonal challenge task, and mood ratings before and immediately after the task. Before and during the challenge task, adolescents' respiratory sinus arrhythmia (an indicator of cardiac vagal tone) was recorded. Associations were tested between adolescents' perceptions of family enmeshment and 3 aspects of adolescent emotional dysregulation. Adolescents who perceived higher family enmeshment also demonstrated greater emotional dysregulation in several domains: negative global appraisals of distress tolerance, stronger increase in subjective negative mood from baseline to postchallenge, lower baseline vagal tone, and vagal augmentation during the challenge task. Gender differences also emerged, such that girls reported more negative distress appraisals overall and enmeshed boys showed greater emotional dysregulation across analyses. Findings are discussed in terms of how clinicians may dynamically assess and treat enmeshment and emotional dysregulation in families with male and female adolescents. (c) 2015 APA, all rights reserved).
Skowron, Elizabeth A; Cipriano-Essel, Elizabeth; Gatzke-Kopp, Lisa M; Teti, Douglas M; Ammerman, Robert T
2014-07-01
This study examined parasympathetic physiology as a moderator of the effects of early adversity (i.e., child abuse and neglect) on children's inhibitory control. Children's respiratory sinus arrhythmia (RSA) was assessed during a resting baseline, two joint challenge tasks with mother, and an individual frustration task. RSA assessed during each of the joint parent-child challenge tasks moderated the effects of child maltreatment (CM) status on children's independently-assessed inhibitory control. No moderation effect was found for RSA assessed at baseline or in the child-alone challenge task. Among CM-exposed children, lower RSA levels during the joint task predicted the lowest inhibitory control, whereas higher joint task RSA was linked to higher inhibitory control scores that were indistinguishable from those of non-CM children. Results are discussed with regard to the importance of considering context specificity (i.e., individual and caregiver contexts) in how biomarkers inform our understanding of individual differences in vulnerability among at-risk children. © 2013 Wiley Periodicals, Inc.
Miller, Jonas G.; Chocol, Caroline; Nuselovici, Jacob N.; Utendale, William T.; Simard, Melissa; Hastings, Paul D.
2014-01-01
This study examined the moderating effects of child temperament on the association between maternal socialization and 4–6-year-old children’s dynamic respiratory sinus arrhythmia (RSA) change in response to anger-themed emotional materials (N = 180). We used latent growth curve modeling to explore adaptive patterns of dynamic RSA change in response to anger. Greater change in RSA during anger-induction, characterized by more initial RSA suppression and a subsequent return to baseline, was related to children’s better regulation of aggression. For anger-themed materials, low levels of authoritarian parenting predicted more RSA suppression and recovery for more anger-prone children, whereas more authoritative parenting predicted more RSA suppression and recovery for less anger-prone children. These findings suggest that children’s adaptive patterns of dynamic RSA change can be characterized by latent growth curve modeling, and that these patterns may be differentially shaped by parent socialization experiences as a function of child temperament. PMID:23274169
Davis, Molly; Suveg, Cynthia; Whitehead, Monica; Jones, Anna; Shaffer, Anne
2016-01-01
To identify factors that can both exacerbate risk for, and protect against, internalizing problems during early childhood, the present study examined whether children’s respiratory sinus arrhythmia (RSA) suppression in response to emotionally-laden film clips would moderate the association between maternal and child anxious/depressive symptoms in a cross-sectional sample of 108 mothers (M age = 30.68 years, SD = 6.06) and their preschool-age children (M age = 3.50 years, SD = .52, 61.00% male). Results indicated that RSA suppression in response to the fear clip moderated the positive association between maternal and child anxious/depressive symptoms, such that higher suppression served a protective-stabilizing function while lower suppression exacerbated children’s risk for internalizing symptoms in the context of higher maternal symptoms. Moderation findings involving RSA suppression in response to a happiness-inducing clip were consistent with biological sensitivity to context; the association between maternal and child symptoms was strongest for children higher in suppression. PMID:27045275
Liu, Siwei; Gates, Kathleen M; Blandon, Alysia Y
2018-06-01
Despite recent research indicating that interpersonal linkage in physiology is a common phenomenon during social interactions, and the well-established role of respiratory sinus arrhythmia (RSA) in socially facilitative physiological regulation, little research has directly examined interpersonal influences in RSA, perhaps due to methodological challenges in analyzing multivariate RSA data. In this article, we aim to bridge this methodological gap by introducing a new method for quantifying interpersonal RSA influences. Specifically, we show that a frequency-domain statistic, generalized partial directed coherence (gPDC), can be used to capture lagged relations in RSA between social partners without first estimating RSA for each person. We illustrate its utility by examining the relation between gPDC and marital conflict in a sample of married couples. Finally, we discuss how gPDC complements existing methods in the time domain and provide guidelines for choosing among these different statistical techniques. © 2018 Society for Psychophysiological Research.
Emotion suppression moderates the quadratic association between RSA and executive function
Spangler, Derek P.; Bell, Martha Ann; Deater-Deckard, Kirby
2016-01-01
There is uncertainty about whether respiratory sinus arrhythmia (RSA), a cardiac marker of adaptive emotion regulation, is involved in relatively low or high executive function performance. In the present study, we investigated: (1) whether RSA during rest and tasks predict both relatively low and high executive function within a larger quadratic association among the two variables, and (2) the extent to which this quadratic trend was moderated by individual differences in emotion regulation. To achieve these aims, a sample of ethnically and socioeconomically diverse women self-reported reappraisal and emotion suppression. They next experienced a two-minute resting period during which ECG was continually assessed. In the next phase, the women completed an array of executive function and non-executive cognitive tasks while ECG was measured throughout. As anticipated, resting RSA showed a quadratic association with executive function that was strongest for high suppression. These results suggest that relatively high resting RSA may predict poor executive function ability when emotion regulation consumes executive control resources needed for ongoing cognitive performance. PMID:26018941
Dynamic measures of RSA predict distress and regulation in toddlers.
Brooker, Rebecca J; Buss, Kristin A
2010-05-01
In this study, we examined a new method for quantifying individual variability using dynamic measures of respiratory sinus arrhythmia (RSA). This method incorporated temporal variation into the measurement of RSA and provided information beyond that offered by more traditional quantifications such as difference scores. Dynamic and static measures of change in RSA were tested in relation to displays of emotion and affective behaviors during a fear-eliciting episode in a sample of 88 typically developing and high-fear toddlers during a laboratory visit at age 24 months. Dynamic measures of RSA contributed information that was unique from traditionally employed, static change scores in predicting high-fear toddlers' displays of shyness during a fear-eliciting episode. In contrast, RSA change scores offered information related to boldness in nonhigh-fear children. In addition, several associations included estimates of nonlinear change in RSA. Implications for the study of individual differences in RSA and relations with emotion and emotion regulation are discussed.
Changes in Physiology before, during, and after Yawning
Corey, Timothy P.; Shoup-Knox, Melanie L.; Gordis, Elana B.; Gallup, Gordon G.
2011-01-01
The ultimate function of yawning continues to be debated. Here, we examine physiological measurements taken before, during, and after yawns in humans, in an attempt to identify key proximate mechanisms associated with this behavior. In two separate studies we measured changes in heart rate, lung volume, eye closure, skin conductance, ear pulse, respiratory sinus arrhythmia, and respiratory rate. Data were depicted from 75 s before and after yawns, and analyzed at baseline, during, and immediately following yawns. Increases in heart rate, lung volume, and eye muscle tension were observed during or immediately following yawning. Patterns of physiological changes during yawning were then compared to data from non-yawning deep inhalations. In one study, respiration period increased following the execution of a yawn. Much of the variance in physiology surrounding yawning was specific to the yawning event. This was not the case for deep inhalation. We consider our findings in light of various hypotheses about the function of yawning and conclude that they are most consistent with the brain cooling hypothesis. PMID:22319494
Innocence and resisting confession during interrogation: effects on physiologic activity.
Guyll, Max; Madon, Stephanie; Yang, Yueran; Lannin, Daniel G; Scherr, Kyle; Greathouse, Sarah
2013-10-01
Innocent suspects may not adequately protect themselves during interrogation because they fail to fully appreciate the danger of the situation. This experiment tested whether innocent suspects experience less stress during interrogation than guilty suspects, and whether refusing to confess expends physiologic resources. After experimentally manipulating innocence and guilt, 132 participants were accused and interrogated for misconduct, and then pressured to confess. Systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), respiratory sinus arrhythmia (RSA), and preejection period (PEP) responses quantified stress reactions. As hypothesized, the innocent evidenced smaller stress responses to interrogation for SBP, DBP, HR, and RSA than did the guilty. Furthermore, innocents who refused to confess exhibited greater sympathetic nervous system activation, as evidenced by shorter PEPs, than did innocent or guilty confessors. These findings suggest that innocent suspects underestimate the threat of interrogation and that resisting pressures to confess can diminish suspects' physiologic resources and lead to false confessions. PsycINFO Database Record (c) 2013 APA, all rights reserved
Cardiac vagal control as a prospective predictor of anxiety in women diagnosed with breast cancer.
Kogan, Anya V; Allen, John J B; Weihs, Karen L
2012-04-01
Low cardiac vagal control (CVC) has been associated with state and trait anxiety and anxiety spectrum disorders. Studies indicate that diagnosis and treatments for breast cancer may be associated with anxiety. The current study examined whether CVC prospectively predicted a trajectory of change in anxiety following breast cancer diagnosis. Forty-three women diagnosed with non-metastatic breast cancer completed the Taylor Manifest Anxiety Scale and the Perceived Stress Scale, and a 5-min resting electrocardiographic (ECG) segment was recorded. Self-report measures were completed approximately every 3 months for a year. Respiratory sinus arrhythmia (RSA) significantly predicted the trajectory of change in anxiety over the follow-up period: participants with higher baseline RSA evidenced decreasing anxiety, whereas those with lower baseline RSA had increasing anxiety. These results are consistent with the hypothesis that CVC facilitates the modulation of anxiety in women coping with significant stressors of breast cancer diagnosis and treatment. Copyright © 2012 Elsevier B.V. All rights reserved.
Too much of a good thing? Cardiac vagal tone's nonlinear relationship with well-being.
Kogan, Aleksandr; Gruber, June; Shallcross, Amanda J; Ford, Brett Q; Mauss, Iris B
2013-08-01
Parasympathetic regulation of heart rate through the vagus nerve--often measured as resting respiratory sinus arrhythmia or cardiac vagal tone (CVT)--is a key biological correlate of psychological well-being. However, recent theorizing has suggested that many biological and psychological processes can become maladaptive when they reach extreme levels. This raises the possibility that CVT might not have an unmitigated positive relationship with well-being. In line with this reasoning, across 231 adult participants (Mage = 40.02 years; 52% female), we found that CVT was quadratically related to multiple measures of well-being, including life satisfaction and depressive symptoms. Individuals with moderate CVT had higher well-being than those with low or high CVT. These results provide the first direct evidence of a nonlinear relationship between CVT and well-being, adding to a growing body of research that has suggested some biological processes may cease being adaptive when they reach extreme levels. PsycINFO Database Record (c) 2013 APA, all rights reserved.
de Wied, Minet; van Boxtel, Anton; Matthys, Walter; Meeus, Wim
2012-02-01
This study examined empathy-related responding in male adolescents with disruptive behavior disorder (DBD), high or low on callous-unemotional (CU) traits. Facial electromyographic (EMG) and heart rate (HR) responses were monitored during exposure to empathy-inducing film clips portraying sadness, anger or happiness. Self-reports were assessed afterward. In agreement with expectations, DBD adolescents with high CU traits showed significantly lower levels of empathic sadness than healthy controls across all response systems. Between DBD subgroups significant differences emerged at the level of autonomic (not verbal or facial) reactions to sadness, with high CU respondents showing less HR change from baseline than low CU respondents. The study also examined basal patterns of autonomic function. Resting HR was not different between groups, but resting respiratory sinus arrhythmia (RSA) was significantly lower in DBD adolescents with high CU traits compared to controls. Results support the notion that CU traits designate a distinct subgroup of DBD individuals.
Garcia, Jose R; Campbell, Peter F; Kumar, Gautam; Langberg, Jonathan J; Cesar, Liliana; Deppen, Juline N; Shin, Eric Y; Bhatia, Neal K; Wang, Lanfang; Xu, Kai; Schneider, Frank; Robinson, Brian; García, Andrés J; Levit, Rebecca D
2018-05-01
Atrial fibrillation (AF) is the most common cardiac arrhythmia. Although treatment options for AF exist, many patients cannot be maintained in normal sinus rhythm. Amiodarone is an effective medication for AF but has limited clinical utility because of off-target tissue toxicity. Here, we use a pig model of AF to test the efficacy of an amiodarone-containing polyethylene glycol-based hydrogel. The gel is placed directly on the atrial epicardium through the pericardial space in a minimally invasive procedure using a specially designed catheter. Implantation of amiodarone-containing gel significantly reduced the duration of sustained AF at 21 and 28 days; inducibility of AF was reduced 14 and 21 days post-delivery. Off-target organ drug levels in the liver, lungs, thyroid, and fat were significantly reduced in animals treated with epicardial amiodarone gel compared with systemic controls in small-animal distribution studies. The pericardium is an underutilized therapeutic site and may be a new treatment strategy for AF and other cardiovascular diseases. © 2018 American Heart Association, Inc.
Cardiovascular manifestations of phaeochromocytoma.
Prejbisz, Aleksander; Lenders, Jacques W M; Eisenhofer, Graeme; Januszewicz, Andrzej
2011-11-01
Clinical expression of phaeochromocytoma may involve numerous cardiovascular manifestations, but usually presents as sustained or paroxysmal hypertension associated with other signs and symptoms of catecholamine excess. Most of the life-threatening cardiovascular manifestations of phaeochromocytoma, such as hypertensive emergencies, result from a rapid and massive release of catecholamines from the tumour. More rarely, patients with phaeochromocytoma present with low blood pressure or even shock that may then precede multisystem crisis. Sinus tachycardia, with palpitations as the presenting symptom, is the most prevalent abnormality of cardiac rhythm in phaeochromocytoma, but tumours can also be associated with more serious ventricular arrhythmias or conduction disturbances. Reversible dilated or hypertrophic cardiomyopathy are well established cardiac manifestations of phaeochromocytoma, with more recent attention to an increasing number of cases with Takotsubo cardiomyopathy. This review provides an update on the cause, clinical presentation and treatment of the cardiovascular manifestations of phaeochromocytoma. As the cardiovascular complications of phaeochromocytoma can be life-threatening, all patients who present with manifestations that even remotely suggest excessive catecholamine secretion should be screened for the disease.
Oliver, Michele L.; Nigg, Joel T.; Cassavaugh, Nicholas D.; Backs, Richard W.
2015-01-01
Objective The present study examined the role of negative emotions on driving performance in relation to ADHD, by comparing young adults scoring high on measures of ADHD (n = 20) with a control group (n = 22). Method The authors used cardiorespiratory physiological measures, simulated driving behavior, and self-report to examine how participants with high and low ADHD symptoms responded to frustration and to determine how frustration affected simulated driving performance. Results Groups did not differ in operational driving skills, but participants with high ADHD symptoms reported more frustration and exhibited more impairment at the tactical level of driving performance than the controls. There was significant suppression of respiratory sinus arrhythmia from resting baseline during tasks, but it did not differ between groups during driving. Conclusion This article proposes that remedial driver training for ADHD populations should focus more on the control of negative emotions rather than on attention or fundamental driving skills. PMID:21490175
Martinelli, L; Goggi, C; Graffigna, A; Salerno, J A; Chimienti, M; Klersy, C; Viganò, M
1987-01-01
The purpose of this report is to present a 5 year experience in electrophysiologically guided surgical treatment of post-infarction ventricular tachycardia (VT) in a consecutive series of 39 patients. In every case the arrhythmia was not responsive to pluripharmacological therapy. The diagnostic steps included preoperative endocardial, intraoperative epi- and endocardial mapping, automatically carried out when possible. Surgical techniques were: classic Guiraudon's encircling endocardial ventriculotomy (EEV), partial EEV, endocardial resection (ER), cryoablation or combined procedures. The hospital mortality was of 4 patients (10%). During the follow-up period (1-68 mo), 4 patients (11%) died of cardiac non-VT related causes. Among the survivors, 90% are in sinus rhythm. The authors consider electrophysiologically guided surgery a safe and reliable method for the treatment of post-infarction VT and suggest more extensive indications. They stress the importance of automatic mapping in pleomorphic and non-sustained VT, and the necessity of tailoring the surgical technique to the characteristics of each case.
Eliciting Affect via Immersive Virtual Reality: A Tool for Adolescent Risk Reduction
Houck, Christopher D.; Barker, David H.; Garcia, Abbe Marrs; Spitalnick, Josh S.; Curtis, Virginia; Roye, Scott; Brown, Larry K.
2014-01-01
Objective A virtual reality environment (VRE) was designed to expose participants to substance use and sexual risk-taking cues to examine the utility of VR in eliciting adolescent physiological arousal. Methods 42 adolescents (55% male) with a mean age of 14.54 years (SD = 1.13) participated. Physiological arousal was examined through heart rate (HR), respiratory sinus arrhythmia (RSA), and self-reported somatic arousal. A within-subject design (neutral VRE, VR party, and neutral VRE) was utilized to examine changes in arousal. Results The VR party demonstrated an increase in physiological arousal relative to a neutral VRE. Examination of individual segments of the party (e.g., orientation, substance use, and sexual risk) demonstrated that HR was significantly elevated across all segments, whereas only the orientation and sexual risk segments demonstrated significant impact on RSA. Conclusions This study provides preliminary evidence that VREs can be used to generate physiological arousal in response to substance use and sexual risk cues. PMID:24365699
Growth Models of Dyadic Synchrony and Mother-Child Vagal Tone in the Context of Parenting At-Risk
Giuliano, Ryan J.; Skowron, Elizabeth A.; Berkman, Elliot T.
2015-01-01
We used multilevel modeling to examine dynamic changes in respiratory sinus arrhythmia (RSA) and observer-coded interactive synchrony for mother-child dyads engaged in a laboratory interaction, to characterize parenting-at-risk. Seventy-nine preschooler-mother dyads including a subset with documented child maltreatment (CM; n=43) were observed completing a joint puzzle task while physiological measures were recorded. Dyads led by CM mothers showed decreases in positive synchrony over time, whereas no variation was observed in non-CM dyads. Growth models of maternal RSA indicated that mothers who maintained high levels of positive interactive synchrony with their child evidenced greater RSA reactivity, characterized by an initial withdrawal followed by augmentation as the task progressed, after accounting for CM group status. These results help to clarify patterns of RSA responding in the context of caregiver-child interactions, and demonstrate the importance of modeling dynamic changes in physiology over time in order to better understanding biological correlates of parenting-at-risk. PMID:25542759
Kuo, Janice R.; Linehan, Marsha M.
2014-01-01
This study investigated Linehan’s (1993) theory that individuals meeting criteria for borderline personality disorder (BPD) have high biological vulnerability to emotion dysregulation, including high baseline emotional intensity and high reactivity to emotionally-evocative stimuli. Twenty individuals with BPD, 20 age-matched individuals with generalized social anxiety disorder (SAD), and 20 age-matched normal controls (NC) participated in two separate emotion induction conditions, a standardized condition and a personally-relevant condition. Respiratory sinus arrhythmia (RSA), skin conductance response (SCR), and self-report measures were collected throughout the experiment. BPD participants displayed heightened biological vulnerability compared with NC as indicated by reduced basal RSA. BPD participants also exhibited high baseline emotional intensity, characterized by heightened SCR and heightened self-reported negative emotions at baseline. However, the BPD group did not display heightened reactivity as their physiological and self-reported changes from baseline to the emotion inductions tasks were not greater than the other two groups. PMID:19685950
Suurland, J; van der Heijden, K B; Huijbregts, S C J; van Goozen, S H M; Swaab, H
2017-09-01
Nonreciprocal action of the parasympathetic (PNS) and sympathetic (SNS) nervous systems, increases susceptibility to emotional and behavioral problems in children exposed to adversity. Little is known about the PNS and SNS in interaction with early adversity during infancy. Yet this is when the physiological systems involved in emotion regulation are emerging and presumably most responsive to environmental influences. We examined whether parasympathetic respiratory sinus arrhythmia (RSA) and sympathetic pre-ejection period (PEP) response and recovery at six months, moderate the association between cumulative prenatal risk and physical aggression at 20 months (N=113). Prenatal risk predicted physical aggression, but only in infants exhibiting coactivation of PNS and SNS (i.e., increase in RSA and decrease in PEP) in response to stress. These findings indicate that coactivation of the PNS and SNS in combination with prenatal risk is a biological marker for the development of aggression. Copyright © 2017 Elsevier B.V. All rights reserved.
Skowron, Elizabeth A.; Cipriano-Essel, Elizabeth; Gatzke-Kopp, Lisa M.; Teti, Douglas M.; Ammerman, Robert T.
2014-01-01
This study examined parasympathetic physiology as a moderator of the effects of early adversity (i.e., child abuse and neglect) on children’s inhibitory control. Children’s respiratory sinus arrhythmia (RSA) was assessed during a resting baseline, two joint challenge tasks with mother, and an individual frustration task. RSA assessed during each of the joint parent–child challenge tasks moderated the effects of child maltreatment (CM) status on children’s independently-assessed inhibitory control. No moderation effect was found for RSA assessed at baseline or in the child-alone challenge task. Among CM-exposed children, lower RSA levels during the joint task predicted the lowest inhibitory control, whereas higher joint task RSA was linked to higher inhibitory control scores that were indistinguishable from those of non-CM children. Results are discussed with regard to the importance of considering context specificity (i.e., individual and caregiver contexts) in how biomarkers inform our understanding of individual differences in vulnerability among at-risk children. PMID:24142832
Sucu, Murat; Davutoglu, Vedat; Ozer, Orhan
2009-01-01
External electrical cardioversion was first performed in the 1950s. Urgent or elective cardioversions have specific advantages, such as termination of atrial and ventricular tachycardia and recovery of sinus rhythm. Electrical cardioversion is life-saving when applied in urgent circumstances. The succcess rate is increased by accurate tachycardia diagnosis, careful patient selection, adequate electrode (paddles) application, determination of the optimal energy and anesthesia levels, prevention of embolic events and arrythmia recurrence and airway conservation while minimizing possible complications. Potential complications include ventricular fibrillation due to general anesthesia or lack of synchronization between the direct current (DC) shock and the QRS complex, thromboembolus due to insufficient anticoagulant therapy, non-sustained VT, atrial arrhythmia, heart block, bradycardia, transient left bundle branch block, myocardial necrosis, myocardial dysfunction, transient hypotension, pulmonary edema and skin burn. Electrical cardioversion performed in patients with a pacemaker or an incompatible cardioverter defibrillator may lead to dysfunction, namely acute or chronic changes in the pacing or sensitivity threshold. Although this procedure appears fairly simple, serious consequences might occur if inappropriately performed. PMID:19448376
Aconite poisoning with arrhythmia and shock.
Tak, Sandeep; Lakhotia, Manoj; Gupta, Alok; Sagar, Amit; Bohra, Gopal; Bajari, Rajesh
2016-09-01
A 55-year-old male presented with history of nausea, vomiting, palpitation paresthesis and profuse sweating in emergency department 2h after ingestion of "Bachnaag" (Aconite) root. Examination revealed shock with irregular pulses. Initial ECG showed frequent multifocal ventricular ectopics (VE), which later turned to short runs of ventricular tachycardia (VT). Immediate gastric lavage was done and activated charcoal given. Patient was treated with fluid resuscitation without any improvement in blood pressure. Patient was started on nor-adrenaline infusion with gradual recovery from hypotension over a period of 6h, but support was continued for 48h. Amiodarone was started to control ventricular excitability, which persisted over 72h with gradual decrease in frequency of VT and VE. Patient was discharged with normal sinus rhythm on oral amiodarone on 5th day of hospitalization. On follow-up after 2 weeks patient was totally asymptomatic and amiodarone was stopped. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.
Giuliano, Ryan J; Roos, Leslie E; Farrar, Jessica D; Skowron, Elizabeth A
2018-04-01
A child's cumulative risk for early exposure to stress has been linked to alterations of self-regulation outcomes, including neurobiological correlates of inhibitory control (IC). We examined whether children's ability to engage the parasympathetic nervous system impacts how risk affects IC. Children ages 3-5 years completed two laboratory measures of IC while respiratory sinus arrhythmia (RSA) was measured, indexing parasympathetic activity. Children with greater risk demonstrated lower IC; risk also moderated associations between RSA reactivity and IC. For children with less risk, greater RSA withdrawal during IC tasks was associated with better IC. In contrast, greater risk was associated with poor IC, regardless of RSA withdrawal. Effects of risk were more pronounced for cumulative than individual measures. Results suggest that cumulative risk exposure disrupts connectivity between physiological and behavioral components of self-regulation in early childhood. Parasympathetic withdrawal to cognitive tasks may be less relevant for performance in developmental samples experiencing greater life stress. © 2018 Wiley Periodicals, Inc.
Song, Ju-Hyun; Colasante, Tyler; Malti, Tina
2018-06-01
Although emotionally well-regulated children are more likely to behave prosocially, the psychological processes that connect their emotion regulation abilities and prosocial behavior are less clear. We tested if other-oriented sympathy and trust mediated the links between emotion regulation capacities (i.e., resting respiratory sinus arrhythmia [RSA], negative emotional intensity, and sadness regulation) and prosocial behavior in an ethnically diverse sample of 4- and 8-year-olds (N = 131; 49% girls). Resting RSA was calculated from children's electrocardiogram data in response to a nondescript video. Sympathy was child and caregiver reported, whereas negative emotional intensity, sadness regulation, trust, and prosocial behavior were caregiver reported. Regardless of age, higher resting RSA was linked to higher sympathy, which was associated with higher prosocial behavior. The positive link between sadness regulation and prosocial behavior was mediated by higher sympathy and trust. Children's other-oriented psychological processes may play important roles in translating certain emotion regulation capacities into prosocial behavior. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Enjoji, Yoshihisa; Mizobuchi, Masahiro; Muranishi, Hiromi; Miyamoto, Chinae; Utsunomiya, Makoto; Funatsu, Atsushi; Kobayashi, Tomoko; Nakamura, Shigeru
2009-12-01
Ventricular fibrillation (VF) or ventricular tachycardia (VT) storm is a life-threatening arrhythmia. Antiarrhythmic drugs (AADs) are not necessarily effective to rescue life from such conditions. Catheter ablation (CA) targeting triggering premature ventricular contractions (PVCs) of VF or VT that originates from Purkinje fiber network (PFN) is reported to be effective, especially in idiopathic patients. However, in condition of acute coronary syndrome (ACS), the efficacy of CA is not well understood. To clarify the usefulness of CA as an alternative way to AADs, we performed CA in four patients with VF or VT storm. The Purkinje potential was seen just before the myocardial ventricular wave during sinus rhythm that became more prominent and double components during the initiating PVC at the targeted area. Following CA, spontaneous episodes of VF or VT were no longer observed. CA is an efficacious way to bail out PFN-related VF or VT storm even in ACS.
Extracting the respiration cycle lengths from ECG signal recorded with bed sheet electrodes
NASA Astrophysics Data System (ADS)
Vehkaoja, A.; Peltokangas, M.; Lekkala, J.
2013-09-01
A method for recognizing the respiration cycle lengths from the electrocardiographic (ECG) signal recorded with textile electrodes that are attached to a bed sheet is proposed. The method uses two features extracted from the ECG that are affected by the respiration: respiratory sinus arrhythmia and the amplitude of the R-peaks. The proposed method was tested in one hour long recordings with ten healthy young adults. A relative mean absolute error of 5.6 % was achieved when the algorithm was able to provide a result for approximately 40 % of the time. 90 % of the values were within 0.5 s and 97 % within 1 s from the reference respiration value. In addition to the instantaneous respiration cycle lengths, also the mean values during 1 and 5 minutes epochs are calculated. The effect of the ECG signal source is evaluated by calculating the result also from the simultaneously recorded reference ECG signal. The acquired respiration information can be used in the estimation of sleep quality and the detection of sleep disorders.
Davis, Molly; Thomassin, Kristel; Bilms, Joanie; Suveg, Cynthia; Shaffer, Anne; Beach, Steven R H
2017-05-01
This study examined three potential moderators of the relations between maternal parenting stress and preschoolers' adjustment problems: a genetic polymorphism-the short allele of the serotonin transporter (5-HTTLPR, ss/sl allele) gene, a physiological indicator-children's baseline respiratory sinus arrhythmia (RSA), and a behavioral indicator-mothers' reports of children's negative emotionality. A total of 108 mothers (M age = 30.68 years, SD age = 6.06) reported on their parenting stress as well as their preschoolers' (M age = 3.50 years, SD age = 0.51, 61% boys) negative emotionality and internalizing, externalizing, and sleep problems. Results indicated that the genetic sensitivity variable functioned according to a differential susceptibility model; however, the results involving physiological and behavioral sensitivity factors were most consistent with a diathesis-stress framework. Implications for prevention and intervention efforts to counter the effects of parenting stress are discussed. © 2017 Wiley Periodicals, Inc.
Whedon, Margaret; Perry, Nicole B; Calkins, Susan D; Bell, Martha Ann
2018-05-21
Parasympathetic nervous system functioning in infancy may serve a foundational role in the development of cognitive and socioemotional skills (Calkins, 2007). In this study (N = 297), we investigated the potential indirect effects of cardiac vagal regulation in infancy on children's executive functioning and social competence in preschool via expressive and receptive language in toddlerhood. Vagal regulation was assessed at 10 months during two attention conditions (social, nonsocial) via task-related changes in respiratory sinus arrhythmia (RSA). A path analysis revealed that decreased RSA from baseline in the nonsocial condition and increased RSA in the social condition were related to larger vocabularies in toddlerhood. Additionally, children's vocabulary sizes were positively related to their executive function and social competence in preschool. Indirect effects from vagal regulation in both contexts to both 4-year outcomes were significant, suggesting that early advances in language may represent a mechanism through which biological functioning in infancy impacts social and cognitive functioning in childhood. © 2018 Wiley Periodicals, Inc.
Miller, Jonas G; Chocol, Caroline; Nuselovici, Jacob N; Utendale, William T; Simard, Melissa; Hastings, Paul D
2013-02-01
This study examined the moderating effects of child temperament on the association between maternal socialization and 4-6-year-old children's dynamic respiratory sinus arrhythmia (RSA) change in response to anger-themed emotional materials (N=180). We used latent growth curve modeling to explore adaptive patterns of dynamic RSA change in response to anger. Greater change in RSA during anger-induction, characterized by more initial RSA suppression and a subsequent return to baseline, was related to children's better regulation of aggression. For anger-themed materials, low levels of authoritarian parenting predicted more RSA suppression and recovery for more anger-prone children, whereas more authoritative parenting predicted more RSA suppression and recovery for less anger-prone children. These findings suggest that children's adaptive patterns of dynamic RSA change can be characterized by latent growth curve modeling, and that these patterns may be differentially shaped by parent socialization experiences as a function of child temperament. Copyright © 2013 Elsevier B.V. All rights reserved.
Hasselmo, Karen; Sbarra, David A; O'Connor, Mary-Frances; Moreno, Francisco A
2015-06-01
Marital separation is linked to negative mental and physical health; however, the strength of this link may vary across people. This study examined changes in respiratory sinus arrhythmia (RSA), used to assess cardiac vagal control, in recently separated adults (N = 79; M time since separation = 3.5 months). When reflecting on the separation, self-reported psychological distress following the separation interacted with a polymorphism in the serotonin transporter gene (5-HTTLPR) and a relevant single nucleotide polymorphism (SNP), rs25531, to predict RSA. Among people reporting emotional difficulties after the separation, those who were homozygous for the short allele had lower RSA levels while reflecting on their relationship than other genotypes. The findings, although limited by the relatively small sample size, are discussed in terms of how higher-sensitivity genotypes may interact with psychological responses to stress to alter physiology. © 2015 Society for Psychophysiological Research.
The Role of Negative Affect and Physiological Regulation in maternal attribution
Wang, Zhe; Deater-Deckard, Kirby; Bell, Martha Ann
2016-01-01
SYNOPSIS Objective Mothers who attribute child misbehaviors to children’s intentions, and not to situational causes, show more hostile parenting behaviors. Why are some mothers more likely than others to make more hostile attributions (i.e., high intentional attributions and low situational attributions) when confronted with child challenging behaviors? We examined the relation between mothers’ perception of child challenging behaviors and their hostile attributions of child misbehaviors, with an emphasis on how maternal negative affect and resting vagal activity moderated this relation. Design 160 mothers of 3- to 7-year-old children reported their perceptions of child problem behaviors, their attributions regarding child misbehaviors, and their temperamental negative affect. Mothers’ respiratory sinus arrhythmia (RSA) was measured during resting state. Results Maternal perceptions of child challenging behaviors were positively related to hostile maternal attributions, and this relation was strongest in mothers with high negative affect and low resting RSA. Conclusions These findings indicate the importance of considering mothers’ affective and physiological attributes when examining social-cognitive processes in parenting. PMID:27667969
Kogan, Aleksandr; Oveis, Christopher; Carr, Evan W; Gruber, June; Mauss, Iris B; Shallcross, Amanda; Impett, Emily A; van der Lowe, Ilmo; Hui, Bryant; Cheng, Cecilia; Keltner, Dacher
2014-12-01
In the present article, we introduce the quadratic vagal activity-prosociality hypothesis, a theoretical framework for understanding the vagus nerve's involvement in prosociality. We argue that vagus nerve activity supports prosocial behavior by regulating physiological systems that enable emotional expression, empathy for others' mental and emotional states, the regulation of one's own distress, and the experience of positive emotions. However, we contend that extremely high levels of vagal activity can be detrimental to prosociality. We present 3 studies providing support for our model, finding consistent evidence of a quadratic relationship between respiratory sinus arrhythmia--the degree to which the vagus nerve modulates the heart rate--and prosociality. Individual differences in vagal activity were quadratically related to prosocial traits (Study 1), prosocial emotions (Study 2), and outside ratings of prosociality by complete strangers (Study 3). Thus, too much or too little vagal activity appears to be detrimental to prosociality. The present article provides the 1st theoretical and empirical account of the nonlinear relationship between vagal activity and prosociality.
Family Financial Stress and Adolescent Sexual Risk-Taking: The Role of Self-Regulation.
Crandall, AliceAnn; Magnusson, Brianna M; Novilla, M Lelinneth B; Novilla, Lynneth Kirsten B; Dyer, W Justin
2017-01-01
The ability to control one's emotions, thoughts, and behaviors is known as self-regulation. Family stress and low adolescent self-regulation have been linked with increased engagement in risky sexual behaviors, which peak in late adolescence and early adulthood. The purpose of this study was to assess whether adolescent self-regulation, measured by parent and adolescent self-report and respiratory sinus arrhythmia, mediates or moderates the relationship between family financial stress and risky sexual behaviors. We assessed these relationships in a 4-year longitudinal sample of 450 adolescents (52 % female; 70 % white) and their parents using structural equation modeling. Results indicated that high family financial stress predicts engagement in risky sexual behaviors as mediated, but not moderated, by adolescent self-regulation. The results suggest that adolescent self-regulatory capacities are a mechanism through which proximal external forces influence adolescent risk-taking. Promoting adolescent self-regulation, especially in the face of external stressors, may be an important method to reduce risk-taking behaviors as adolescents transition to adulthood.
Barry, Samantha A; Rabkin, Ari N; Olezeski, Christy L; Rivers, Alison J; Gordis, Elana B
2015-03-15
The present study examines the impact of the parasympathetic nervous system (PNS), as measured by respiratory sinus arrhythmia (RSA), on the link between family aggression experienced during adolescence and posttraumatic stress symptoms during young adulthood. Participants completed retrospective self-report measures of interparental aggression and harsh parenting exposure during adolescence and measures of current posttraumatic stress symptoms. RSA indexed PNS activity. Among females, the three-way interaction between harsh parenting, interparental aggression, and resting RSA was significant in accounting for young adulthood PTSD symptoms. At higher values of resting RSA and higher levels of interparental aggression exposure, harsh parenting experienced during adolescence was positively associated with adulthood PTSD symptoms. Among males, adolescent aggression exposure and resting RSA did not significantly account for variation in adulthood PTSD symptoms. Thus, this study suggests that resting PNS activity may play an important role in the relationship between stressors during adolescence and later PTSD in females. Copyright © 2015 Elsevier Inc. All rights reserved.
Thyroid storm in a patient with Wolff-Parkinson-White syndrome.
Naqvi, Syed Yaseen; Luebbert, Jeffrey J; Rosen, Stephen G
2015-12-15
A 44-year-old woman with no medical history presented to the emergency department with a 2 h history of sudden onset chest pressure, palpitations, diaphoresis and shortness of breath. She reported a 90-pound unintentional weight loss, increased appetite, irritability, night sweats and palpitations for 2 months. Physical examination revealed a heart rate (HR) of 269 bpm and a blood pressure of 116/94 mm Hg. Her ECG revealed a wide-complex tachycardia with right bundle branch morphology and an HR of 265 bpm. Intravenous adenosine was administered with resolution of the arrhythmia and symptoms. Her subsequent ECG revealed sinus tachycardia with δ waves, which was consistent with Wolff-Parkinson-White (WPW) syndrome. Laboratory findings confirmed thyroid storm and treatment began with intravenous hydrocortisone, methimazole, metoprolol, amiodarone and iodine drops. Graves' disease was confirmed based on the presence of serum thyroid-stimulating hormone receptor antibody. The patient underwent successful WPW accessory tract ablation 6 weeks after initial presentation. 2015 BMJ Publishing Group Ltd.
Cardiac vagal control and children’s adaptive functioning: A meta-analysis
Graziano, Paulo; Derefinko, Karen
2014-01-01
Polyvagal theory has influenced research on the role of cardiac vagal control, indexed by respiratory sinus arrhythmia withdrawal (RSA-W) during challenging states, in children’s self-regulation. However, it remains unclear how well RSA-W predicts adaptive functioning (AF) outcomes and whether certain caveats of measuring RSA (e.g., respiration) significantly impact these associations. A meta-analysis of 44 studies (n = 4,996 children) revealed small effect sizes such that greater levels of RSA-W were related to fewer externalizing, internalizing, and cognitive/academic problems. In contrast, RSA-W was differentially related to children’s social problems according to sample type (community vs. clinical/at-risk). The relations between RSA-W and children’s AF outcomes were stronger among studies that co-varied baseline RSA and in Caucasian children (no effect was found for respiration). Children from clinical/at-risk samples displayed lower levels of baseline RSA and RSA-W compared to children from community samples. Theoretical/practical implications for the study of cardiac vagal control are discussed. PMID:23648264
Right Site, Wrong Route - Cannulating the Left Internal Jugular Vein.
Paik, Peter; Arukala, Sanjay K; Sule, Anupam A
2018-01-09
Central venous catheters are placed in approximately five million patients annually in the US. The preferred site of insertion is one with fewer risks and easier access. Although the right internal jugular vein is preferred, on occasion, the left internal jugular may have to be accessed. A patient was admitted for septic shock, cerebrovascular accident, and non-ST-segment elevation myocardial infarction. A central venous line was needed for antibiotic and vasopressor administration. Due to trauma from a fall to the right side and previously failed catheterization attempts at the left subclavian and femoral veins, the left internal jugular vein was accessed. On chest radiography for confirmation, the left internal jugular central venous catheter was seen projecting down the left paraspinal region. It did not take the expected course across the midline toward the right and into the superior vena cava (SVC). A review of a computed tomography (CT) scan of the chest with contrast done on a prior admission revealed a duplicated SVC on the left side that had not been reported in the original CT scan interpretation. A left-sided SVC is present in approximately 0.3% to 0.5% of the population, with 90% of these draining into the coronary sinus. During placements of central venous lines and pacemakers, irritation of the coronary sinus may result in hypotension, arrhythmia, myocardial ischemia, or cardiac arrest. A widened mediastinum can be an indication of a duplicated SVC. When attempting a left internal jugular vein central venous catheter placement, it is important to be aware of venous anomalies in order to prevent complications.
In vivo dose measurement using TLDs and MOSFET dosimeters for cardiac radiosurgery
Sumanaweera, Thilaka S.; Blanck, Oliver; Iwamura, Alyson K.; Steel, James P.; Dieterich, Sonja; Maguire, Patrick
2012-01-01
In vivo measurements were made of the dose delivered to animal models in an effort to develop a method for treating cardiac arrhythmia using radiation. This treatment would replace RF energy (currently used to create cardiac scar) with ionizing radiation. In the current study, the pulmonary vein ostia of animal models were irradiated with 6 MV X‐rays in order to produce a scar that would block aberrant signals characteristic of atrial fibrillation. The CyberKnife radiosurgery system was used to deliver planned treatments of 20–35 Gy in a single fraction to four animals. The Synchrony system was used to track respiratory motion of the heart, while the contractile motion of the heart was untracked. The dose was measured on the epicardial surface near the right pulmonary vein and on the esophagus using surgically implanted TLD dosimeters, or in the coronary sinus using a MOSFET dosimeter placed using a catheter. The doses measured on the epicardium with TLDs averaged 5% less than predicted for those locations, while doses measured in the coronary sinus with the MOSFET sensor nearest the target averaged 6% less than the predicted dose. The measurements on the esophagus averaged 25% less than predicted. These results provide an indication of the accuracy with which the treatment planning methods accounted for the motion of the target, with its respiratory and cardiac components. This is the first report on the accuracy of CyberKnife dose delivery to cardiac targets. PACS numbers: 87.53.Ly, 87.53.Bn PMID:22584173
Hormonal, Electrolytic, and Electrocardiographic Evaluations in Bitches With Eutocia and Dystocia.
Simões, Carla Regina Barbieri; Vassalo, Flávia Gardilin; Lourenço, Maria Lúcia Gomes; de Souza, Fabiana Ferreira; Oba, Eunice; Sudano, Mateus José; Prestes, Nereu Carlos
2016-12-01
The objective of the study was to assess clinical alterations, electrocardiographic, hematological, biochemical, hemogasometric, electrolytic, and hormone plasma concentrations in bitches with eutocia and dystocia. Overall, 28 bitches (dystocia, n = 22 and eutocia, n = 6) were assessed. The evaluations were performed at 2 time points, M1 (1 hour prepartum-eutocia group and cesarean or clinical intervention-dystocia group) and M2 (postpartum-eutocia or dystocia group and anesthetic recovery-dystocia group). The main clinical finding was the hypothermia (mean: 36.9°C dystocia vs. 36.8°C eutocia). Sinus arrhythmia and tachycardia were the electrocardiographic parameters predominant in eutocia and sinus rhythm in dystocia group. The P wave amplitude, heart rate, creatinine concentration, hematocrit, and hemoglobin were increased in M1 (P < .05), whereas the concentration of TCO 2 was higher in M2. There was an increase in P 4 concentration in dystocia and total T 3 concentrations were increased in M1 in both groups. Total T 4 was higher in dystocia during M1 and in dystocia during M2 in eutocia than in dystocia. We concluded that at 1 hour prepartum or pre-cesarean, there is an increase in heart rate in bitches with eutocia or dystocia, and this finding was correlated to thyroid hormone concentration. P 4 concentrations remained high during dystocia, and hematological and biochemical changes returned to normal after parturition. The evaluation of these parameters in pregnancy can be used as tool to prevent dystocia and consequent fetal death. Copyright © 2016 Elsevier Inc. All rights reserved.
Leptin decreases heart rate associated with increased ventricular repolarization via its receptor.
Lin, Yen-Chang; Huang, Jianying; Hileman, Stan; Martin, Karen H; Hull, Robert; Davis, Mary; Yu, Han-Gang
2015-11-15
Leptin has been proposed to modulate cardiac electrical properties via β-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1-30 μg/kg) decreased resting heart rate; at high doses (150-300 μg/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03-0.3 μg/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of β-adrenergic receptor stimulation. During inhibition of β-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias. Copyright © 2015 the American Physiological Society.
Leptin decreases heart rate associated with increased ventricular repolarization via its receptor
Lin, Yen-Chang; Huang, Jianying; Hileman, Stan; Martin, Karen H.; Hull, Robert; Davis, Mary
2015-01-01
Leptin has been proposed to modulate cardiac electrical properties via β-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1–30 μg/kg) decreased resting heart rate; at high doses (150–300 μg/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03–0.3 μg/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of β-adrenergic receptor stimulation. During inhibition of β-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias. PMID:26408544
Rajaeefard, Abdolreza; Ghorbani, Mohammad; Babaee Baigi, Mohammad Ali; Tabatabae, Hamidreza
2015-01-01
Background: Heart failure is a prevalent disease affecting about 4.9 million people in the U.S. and more than 22 million individuals worldwide. Using electric pacemaker is the most common treatment for the patients with heart conduction problems. The present study aimed to determine the factors affecting survival in the patients undergoing pacemaker implantation in the hospitals affiliated to Shiraz University of Medical Sciences. Objectives: The aim of the present study was to identify the factors affecting the survival of the patients suffering from arrhythmia. Patients and Methods: This retrospective survival analysis was conducted on all 1207 patients with heart failure who had undergone permanent pacemaker implantation in the hospitals affiliated to Shiraz University of Medical Sciences from 2002 to 2012. The data were analyzed using non-parametric methods such as Kaplan-Meier method, life table, and Cox regression model. The risk factors of mortality were determined using multivariate Cox proportional hazards method. Results: Survival data were available for 1030 (80%) patients (median age = 71 years [5th to 95th percentile range: 26 - 86 years]) and follow-up was completed for 84.28% of them. According to the results, 56% of the patients had received dual-chamber systems, while 44% had been implanted by single-chamber ventricular systems. Moreover, sick sinus syndrome and pacemaker mode were independent predictors of increased mortality. Conclusions: In this study, sick sinus syndrome and pacemaker mode followed by syncope were independently associated with increased mortality. PMID:26734484
Sobieszczańska-Małek, Małgorzata; Zieliński, Tomasz; Rywik, Tomasz; Piotrowska, Małgorzata; Religa, Grzegorz; Przybyłowski, Piotr; Rózański, Jacek; Korewicki, Jerzy
2010-01-01
Atrial fibrillation (AF) is the most common arrhythmia among patients (pts) with heart failure and has significant influence on survival. to assess prognosis of pts with refractory heart failure (HF) qualified for heart transplantation (HTX). 872 pts (107 W and 765 M) were qualified for HTX between Dec 2003 and Oct 2007. Patient's death or super urgent heart transplantation were considered the end point in Kaplan-Meier survival curves. 680 pts were on sinus rhythm (SR) and 192(22.0%) had atrial fibrillation (AF). During follow-up (1-1464 days, mean 550 days) 155 pts (17.7%) died, 17.65% with SR and 18.23% with AF (ns). EF - mean 21,6 (SR) and 21,8 (FA), NYHA 3,1 (SR), NTproBNP- mean 3635, 4 (SR) and 4349,4 (FA), Arronson - mean 7,8 (SR) and 7,7 (FA). There were no significant differences between groups. We analyzed influence of heart rate (Kaplan-Maier method) on survival. The pts were divided according to HR: gr.I <70/min, gr II 71-89/min, gr III >90/min. The shortest survival rate was noticed in group III. There was no difference in survival between group I and II. The prognosis for patients qualified for heart transplant does not depend on the type of the dominant cardiac rhythm (atrial fibrillation or sinus rhythm). The prognosis is significantly better for those patients whose basic, resting heart rate does not exceed 90 bpm regardless of the rhythm type.
Avitall, Boaz; Lafontaine, Daniel; Rozmus, Grzegorz; Adoni, Naveed; Dehnee, Abed; Urbonas, Arvydas; Le, Khoi M; Aleksonis, Dinas
2005-04-01
The coronary sinus (CS) can provide access to targets across and within the atrioventricular (AV) junction. In 12 dogs (32 +/- 3 Kg), cryo balloons (10-19 mm) were applied to regions of the AV junction for 3 minutes at a temperature of -75.9( composite function) +/- 9(composite function)C (ranging -57 to -83). Electrical activity and pacing within the CS were assessed pre and post ablation and at least 3 months later in 9 dogs. In the 3 other dogs, hearts were examined immediately after cryo ablation. CS and circumflex angiography was performed pre and post ablation. The hearts, CS, and Cx were then examined for structural injury. The AV junction was sectioned and the hearts were immersed in Tetrazolium, and the lesions were inspected for transmurality across the AV groove. In 3/12 dogs the distal CS cryo lesions resulted in inferior ST segment depression that resolved within 5 minutes. There was no arrhythmia or hemodynamic changes. No CS electrical activity was noted post ablation. The pacing threshold increased from 2 +/- 2.3 mA to 7.4 +/- 3.6 mA (p < 0.001). Pathological examination of 3 acute hearts revealed hematomas. There was no pericardial effusion. No evidence of stenosis or thrombosis was seen within the CS and the circumflex artery. After 3 months of recovery, transmural lesions across the AV groove were present in all of the targeted AV regions. Intra-CS cryo balloon ablation is safe and can potentially replace endocardial RF ablation targeting the AV junction and the CS muscular sleeve.
Hsieh, Dai-Ling; Hsiao, Tzu-Chien
2016-07-04
People with internet addiction (IA) suffer from mental, physical, social, and occupational problems. IA includes psychological and physiological syndromes, and among the syndromes, emotion was suggested important mental and physiological expressions of IA. However, few physiologically emotional characters of IA were investigated. Autonomic nervous system (ANS) activity was a good link between IA and emotion, and respiratory sinus arrhythmia (RSA) gained from ANS was hypothesized related to IA. An emotional induction experiment using negative and positive emotional films was conducted to validate the hypotheses. Thirty-four participants recruited from college were classified into high-risk IA group (HIA) and low-risk IA group (LIA). The respiratory signals, ECG signals, and self-assessed emotional intensity were acquired. The relationship and difference between IA and RSA was tested using descriptive statistics and inferential statistics. The RSA values of HIA were lower than those of LIA both before and after the induction of positive and negative emotions. When participants experienced a negative emotion (anger or fear), their RSA values declined; the decline for HIA was greater than that for LIA. The RSA values of HIA participants before induction of fear, happiness, or surprise, statistically significantly differed from that after induction of those emotions, with p values of 0.007, 0.04 and 0.01 respectively. The difference between the changes in RSA values upon the induction of surprise of HIA and LIA was statistically significant difference (p = 0.03). The interaction between two IA groups among emotional induction states was statistically significant difference. RSA value here was the main variable that reflected ANS activity, and especially vagus nerve regulation. The results revealed that the changes in RSA values were biologically significantly different between HIA and LIA, especially when sadness, happiness, or surprise was induced. HIA people exhibited stronger RSA reactivity following negative emotion than LIA people, but the RSA reactivity following positive emotion was weaker. This study provides more physiological information about IA and assists further investigation on the regulation of the ANS for IA abusers. The results will benefit the further application, early detection, therapy, and even early prevention. Clinical trial registration details This study was approved by the Institution Review Board of the National Taiwan University Hospital, Hsinchu Branch (Hsinchu, Taiwan), under the research project: A study of interactions between cognition, emotion and physiology (contract no.100IRB-32).
... Disease Venous Thromboembolism Aortic Aneurysm More Why Arrhythmia Matters Updated:Dec 21,2016 When the heart's ability ... September 2016. Arrhythmia • Home • About Arrhythmia • Why Arrhythmia Matters • Understand Your Risk for Arrhythmia • Symptoms, Diagnosis & Monitoring ...
Unipolar atrial electrogram morphology from an epicardial and endocardial perspective.
van der Does, Lisette J M E; Knops, Paul; Teuwen, Christophe P; Serban, Corina; Starreveld, Roeliene; Lanters, Eva A H; Mouws, Elisabeth M J P; Kik, Charles; Bogers, Ad J J C; de Groot, Natasja M S
2018-02-22
Endo-epicardial asynchrony (EEA) and the interplay between the endocardial and epicardial layers could be important in the pathophysiology of atrial arrhythmias. The morphologic differences between epicardial and endocardial atrial electrograms have not yet been described, and electrogram morphology may hold information about the presence of EEA. The purpose of this study was to directly compare epicardial to endocardial unipolar electrogram morphology during sinus rhythm (SR) and to evaluate whether EEA contributes to electrogram fractionation by correlating fractionation to spatial activation patterns. In 26 patients undergoing cardiac surgery, unipolar electrograms were simultaneously recorded from the epicardium and endocardium at the inferior, middle, and superior right atrial (RA) free wall during SR. Potentials were analyzed for epi-endocardial differences in local activation time, voltage, RS ratio, and fractionation. The surrounding and opposite electrograms of fractionated deflections were evaluated for corresponding local activation times in order to determine whether fractionation originated from EEA. The superior RA was predisposed to delayed activation, EEA, and fractionation. Both epicardial and endocardial electrograms demonstrated an S-predominance. Fractionation was mostly similar between the 2 sides; however, incidentally deflections up to 4 mV on 1 side could be absent on the other side. Remote activation was responsible for most fractionated deflections (95%) in SR, of which 4% could be attributed to EEA. Local epi-endocardial differences in electrogram fractionation occur occasionally during SR but will likely increase during arrhythmias due to increasing EEA and (functional) conduction disorders. Electrogram fractionation can originate from EEA, and this study demonstrated that unipolar electrogram fractionation can potentially identify EEA. Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Silicon central pattern generators for cardiac diseases
Nogaret, Alain; O'Callaghan, Erin L; Lataro, Renata M; Salgado, Helio C; Meliza, C Daniel; Duncan, Edward; Abarbanel, Henry D I; Paton, Julian F R
2015-01-01
Cardiac rhythm management devices provide therapies for both arrhythmias and resynchronisation but not heart failure, which affects millions of patients worldwide. This paper reviews recent advances in biophysics and mathematical engineering that provide a novel technological platform for addressing heart disease and enabling beat-to-beat adaptation of cardiac pacing in response to physiological feedback. The technology consists of silicon hardware central pattern generators (hCPGs) that may be trained to emulate accurately the dynamical response of biological central pattern generators (bCPGs). We discuss the limitations of present CPGs and appraise the advantages of analog over digital circuits for application in bioelectronic medicine. To test the system, we have focused on the cardio-respiratory oscillators in the medulla oblongata that modulate heart rate in phase with respiration to induce respiratory sinus arrhythmia (RSA). We describe here a novel, scalable hCPG comprising physiologically realistic (Hodgkin–Huxley type) neurones and synapses. Our hCPG comprises two neurones that antagonise each other to provide rhythmic motor drive to the vagus nerve to slow the heart. We show how recent advances in modelling allow the motor output to adapt to physiological feedback such as respiration. In rats, we report on the restoration of RSA using an hCPG that receives diaphragmatic electromyography input and use it to stimulate the vagus nerve at specific time points of the respiratory cycle to slow the heart rate. We have validated the adaptation of stimulation to alterations in respiratory rate. We demonstrate that the hCPG is tuneable in terms of the depth and timing of the RSA relative to respiratory phase. These pioneering studies will now permit an analysis of the physiological role of RSA as well as its any potential therapeutic use in cardiac disease. PMID:25433077
Bedirli, Nurdan; Işık, Berrin; Bashiri, Mehrnoosh; Pampal, Kutluk; Kurtipek, Ömer
2018-01-01
Sugammadex is a cylodextrin derivate that encapsulates steroidal neuromuscular blocker agents and is reported as a safe and well-tolerated drug. In this case report, we present a patient who developed grade 3 anaphylaxis just after sugammadex administration. A 22-year-old woman with diagnosis of Weaver syndrome was scheduled for bilateral mammoplasty and resection of unilateral accessory breast tissue resection. Anesthesia was induced and maintained by propofol, rocuronium, and remifentanil. At the end of the operation, sugammadex was administered and resulted in initially hypotension and bradycardia then the situation worsened by premature ventricular contraction and bigeminy with tachycardia, bronchospasm, and hypoxia. The Ring and Messmer clinical severity scale grade 3 anaphylactic reaction occurred just after sugammadex injection and the patient developed prolonged hypotension with recurrent cardiac arrhythmias in postoperative 12 hours. Treatment was initiated bolus injections of ephedrine, epinephrine, lidocaine, steroids and antihistaminic and continued with lidocaine bolus dosages and norepinephrine infusion for the postoperative period. The general condition of the patient improved to normal 3 hours after the sugammadex injection, and she was moved to the intensive care unit. At 2nd and 8th hours of intensive care unit follow-up, she developed premature ventricular contraction and bigeminy with the heart rate of 130 to 135 beats/min, which returned to sinus rhythm with 50 mg lidocaine. After that, no symptoms were observed and the patient was discharged to plastic surgery clinic at the following day. Sugammadex may result in life-treating anaphylactic reaction even in a patient who did not previously expose to drug. Moreover, prolonged cardiovascular collapse and cardiac arrhythmias may occur. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.
Bedirli, Nurdan; Işık, Berrin; Bashiri, Mehrnoosh; Pampal, Kutluk; Kurtipek, Ömer
2018-01-01
Abstract Rationale: Sugammadex is a cylodextrin derivate that encapsulates steroidal neuromuscular blocker agents and is reported as a safe and well-tolerated drug. In this case report, we present a patient who developed grade 3 anaphylaxis just after sugammadex administration. Patient concerns: A 22-year-old woman with diagnosis of Weaver syndrome was scheduled for bilateral mammoplasty and resection of unilateral accessory breast tissue resection. Anesthesia was induced and maintained by propofol, rocuronium, and remifentanil. At the end of the operation, sugammadex was administered and resulted in initially hypotension and bradycardia then the situation worsened by premature ventricular contraction and bigeminy with tachycardia, bronchospasm, and hypoxia. Diagnosis: The Ring and Messmer clinical severity scale grade 3 anaphylactic reaction occurred just after sugammadex injection and the patient developed prolonged hypotension with recurrent cardiac arrhythmias in postoperative 12 hours. Interventions: Treatment was initiated bolus injections of ephedrine, epinephrine, lidocaine, steroids and antihistaminic and continued with lidocaine bolus dosages and norepinephrine infusion for the postoperative period. Outcomes: The general condition of the patient improved to normal 3 hours after the sugammadex injection, and she was moved to the intensive care unit. At 2nd and 8th hours of intensive care unit follow-up, she developed premature ventricular contraction and bigeminy with the heart rate of 130 to 135 beats/min, which returned to sinus rhythm with 50 mg lidocaine. After that, no symptoms were observed and the patient was discharged to plastic surgery clinic at the following day. Lessons: Sugammadex may result in life-treating anaphylactic reaction even in a patient who did not previously expose to drug. Moreover, prolonged cardiovascular collapse and cardiac arrhythmias may occur. PMID:29505006
Clark, Timothy D; Sandblom, Erik; Cox, Georgina K; Hinch, Scott G; Farrell, Anthony P
2008-11-01
This study was undertaken to provide a comprehensive set of data relevant to disclosing the physiological effects and possible oxygen transport limitations in the Chinook salmon (Oncorhynchus tshawytscha) during an acute temperature change. Fish were instrumented with a blood flow probe around the ventral aorta and catheters in the dorsal aorta and sinus venosus. Water temperature was progressively increased from 13 degrees C in steps of 4 degrees C up to 25 degrees C. Cardiac output increased from 29 to 56 ml.min(-1).kg(-1) between 13 and 25 degrees C through an increase in heart rate (58 to 105 beats/min). Systemic vascular resistance was reduced, causing a stable dorsal aortic blood pressure, yet central venous blood pressure increased significantly at 25 degrees C. Oxygen consumption rate increased from 3.4 to 8.7 mg.min(-1).kg(-1) during the temperature increase, although there were signs of anaerobic respiration at 25 degrees C in the form of increased blood lactate and decreased pH. Arterial oxygen partial pressure was maintained during the heat stress, although venous oxygen partial pressure (Pv(O(2))) and venous oxygen content were significantly reduced. Cardiac arrhythmias were prominent in three of the largest fish (>4 kg) at 25 degrees C. Given the switch to anaerobic metabolism and the observation of cardiac arrhythmias at 25 degrees C, we propose that the cascade of venous oxygen depletion results in a threshold value for Pv(O(2)) of around 1 kPa. At this point, the oxygen supply to systemic and cardiac tissues is compromised, such that the oxygen-deprived and acidotic myocardium becomes arrhythmic, and blood perfusion through the gills and to the tissues becomes compromised.
Effect of high doses of magnesium on converting ibutilide to a safe and more effective agent.
Patsilinakos, Sotirios; Christou, Apostolos; Kafkas, Nikolaos; Nikolaou, Nikolaos; Antonatos, Dionysios; Katsanos, Spyridon; Spanodimos, Stavros; Babalis, Dimitrios
2010-09-01
Ibutilide is a class III antiarrhythmic agent indicated for cardioversion of atrial fibrillation and atrial flutter to sinus rhythm (SR). The most serious complication of ibutilide is torsades de pointes (TdP). Magnesium has been successfully used for the treatment of TdP, but its use as a prophylactic agent for this arrhythmia has not yet been established. The present study investigated whether high dose of magnesium would increase the safety and efficacy of ibutilide administration. A total of 476 patients with atrial fibrillation or atrial flutter who were candidates for conversion to SR were divided into 2 groups. Group A consisted of 229 patients who received ibutilide to convert atrial fibrillation or atrial flutter to SR. Group B consisted of 247 patients who received an intravenous infusion of 5 g of magnesium sulfate for 1 hour followed by the administration of ibutilide. Then, another 5 g of magnesium were infused for 2 additional hours. Of the patients in groups A and B, 154 (67.3%) and 189 (76.5%), respectively, were converted to SR (p = 0.033). Ventricular arrhythmias (sustained, nonsustained ventricular tachycardia, and TdP) occurred significantly more often in group A than in group B (7.4% vs 1.2%, respectively, p = 0.002). TdP developed in 8 patients (3.5%) in group A and in none (0%) in group B (p = 0.009). The administration of magnesium (despite the high doses used) was well tolerated. In conclusion, the administration of high doses of magnesium probably makes ibutilide a much safer agent, and magnesium increased the conversion efficacy of ibutilide. 2010 Elsevier Inc. All rights reserved.
Exploiting periodicity to extract the atrial activity in atrial arrhythmias
NASA Astrophysics Data System (ADS)
Llinares, Raul; Igual, Jorge
2011-12-01
Atrial fibrillation disorders are one of the main arrhythmias of the elderly. The atrial and ventricular activities are decoupled during an atrial fibrillation episode, and very rapid and irregular waves replace the usual atrial P-wave in a normal sinus rhythm electrocardiogram (ECG). The estimation of these wavelets is a must for clinical analysis. We propose a new approach to this problem focused on the quasiperiodicity of these wavelets. Atrial activity is characterized by a main atrial rhythm in the interval 3-12 Hz. It enables us to establish the problem as the separation of the original sources from the instantaneous linear combination of them recorded in the ECG or the extraction of only the atrial component exploiting the quasiperiodic feature of the atrial signal. This methodology implies the previous estimation of such main atrial period. We present two algorithms that separate and extract the atrial rhythm starting from a prior estimation of the main atrial frequency. The first one is an algebraic method based on the maximization of a cost function that measures the periodicity. The other one is an adaptive algorithm that exploits the decorrelation of the atrial and other signals diagonalizing the correlation matrices at multiple lags of the period of atrial activity. The algorithms are applied successfully to synthetic and real data. In simulated ECGs, the average correlation index obtained was 0.811 and 0.847, respectively. In real ECGs, the accuracy of the results was validated using spectral and temporal parameters. The average peak frequency and spectral concentration obtained were 5.550 and 5.554 Hz and 56.3 and 54.4%, respectively, and the kurtosis was 0.266 and 0.695. For validation purposes, we compared the proposed algorithms with established methods, obtaining better results for simulated and real registers.
Martínez-Alanis, Marisol; Ruiz-Velasco, Silvia; Lerma, Claudia
2016-12-15
Most approaches to predict ventricular tachyarrhythmias which are based on RR intervals consider only sinus beats, excluding premature ventricular complexes (PVCs). The method known as heartprint, which analyses PVCs and their characteristics, has prognostic value for fatal arrhythmias on long recordings of RR intervals (>70,000 beats). To evaluate characteristics of PVCs from short term recordings (around 1000 beats) and their prognostic value for imminent sustained tachyarrhythmia. We analyzed 132 pairs of short term RR interval recordings (one before tachyarrhythmia and one control) obtained from 78 patients. Patients were classified into two groups based on the history of accelerated heart rate (HR) (HR>90bpm) before a tachyarrhythmia episode. Heartprint indexes, such as mean coupling interval (meanCI) and the number of occurrences of the most prevalent form of PVCs (SNIB) were calculated. The predictive value of all the indexes and of the combination of different indexes was calculated. MeanCI shorter than 482ms and the occurrence of more repetitive arrhythmias (sNIB≥2.5), had a significant prognostic value for patients with accelerated heart rate: adjusted odds ratio of 2.63 (1.33-5.17) for meanCI and 2.28 (1.20-4.33) for sNIB. Combining these indexes increases the adjusted odds ratio: 10.94 (3.89-30.80). High prevalence of repeating forms of PVCs and shorter CI are potentially useful risk markers of imminent ventricular tachyarrhythmia. Knowing if a patient has history of VT/VF preceded by accelerated HR, improves the prognostic value of these risk markers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Cost-effectiveness of cardioversion and antiarrhythmic therapy in nonvalvular atrial fibrillation.
Catherwood, E; Fitzpatrick, W D; Greenberg, M L; Holzberger, P T; Malenka, D J; Gerling, B R; Birkmeyer, J D
1999-04-20
Physicians managing patients with nonvalvular atrial fibrillation must consider the risks, benefits, and costs of treatments designed to restore and maintain sinus rhythm compared with those of rate control with antithrombotic prophylaxis. To compare the cost-effectiveness of cardioversion, with or without antiarrhythmic agents, with that of rate control plus warfarin or aspirin. A Markov decision-analytic model was designed to simulate long-term health and economic outcomes. Published literature and hospital accounting information. Hypothetical cohort of 70-year-old patients with different baseline risks for stroke. 3 months. Societal. Therapeutic strategies using different combinations of cardioversion alone, cardioversion plus amiodarone or quinidine therapy, and rate control with antithrombotic treatment. Expected costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness. Strategies involving cardioversion alone were more effective and less costly than those not involving this option. For patients at high risk for ischemic stroke (5.3% per year), cardioversion alone followed by repeated cardioversion plus amiodarone therapy on relapse was most cost-effective ($9300 per QALY) compared with cardioversion alone followed by warfarin therapy on relapse. This strategy was also preferred for the moderate-risk cohort (3.6% per year), but the benefit was more expensive ($18,900 per QALY). In the lowest-risk cohort (1.6% per year), cardioversion alone followed by aspirin therapy on relapse was optimal. The choice of optimal strategy and incremental cost-effectiveness was substantially influenced by the baseline risk for stroke, rate of stroke in sinus rhythm, efficacy of warfarin, and costs and utilities for long-term warfarin and amiodarone therapy. Cardioversion alone should be the initial management strategy for persistent nonvalvular atrial fibrillation. On relapse of arrhythmia, repeated cardioversion plus low-dose amiodarone is cost-effective for patients at moderate to high risk for ischemic stroke.
Schmidt, Anders S; Lauridsen, Kasper G; Adelborg, Kasper; Torp, Peter; Bach, Leif F; Jepsen, Simon M; Hornung, Nete; Deakin, Charles D; Rickers, Hans; Løfgren, Bo
2017-03-08
Several different defibrillators are currently used for cardioversion and defibrillation of cardiac arrhythmias. The efficacy of a novel pulsed biphasic (PB) waveform has not been compared to other biphasic waveforms. Accordingly, this study aims to compare the efficacy and safety of PB shocks with biphasic truncated exponential (BTE) shocks in patients undergoing cardioversion of atrial fibrillation or -flutter. This prospective, randomized study included patients admitted for elective direct current cardioversion. Patients were randomized to receive cardioversion using either PB or BTE shocks. We used escalating shocks until sinus rhythm was obtained or to a maximum of 4 shocks. Patients randomized to PB shocks received 90, 120, 150, and 200 J and patients randomized to BTE shocks received 100, 150, 200, and 250 J, as recommended by the manufacturers. In total, 69 patients (51%) received PB shocks and 65 patients (49%) BTE shocks. Successful cardioversion, defined as sinus rhythm 4 hours after cardioversion, was achieved in 43 patients (62%) using PB shocks and in 56 patients (86%) using BTE shocks; ratio 1.4 (95% CI 1.1-1.7) ( P =0.002). There was no difference in safety (ie, myocardial injury judged by changes in high-sensitive troponin I levels; ratio 1.1) (95% CI 1.0-1.3), P =0.15. The study was terminated prematurely because of an adverse event. Cardioversion using a BTE waveform was more effective when compared with a PB waveform. There was no difference in safety between the 2 waveforms, as judged by changes in troponin I levels. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02317029. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
Chen, Jan-Yow; Liou, Ying-Ming; Wu, Hong-Dar Isaac; Lin, Kuo-Hung; Chang, Kuan-Cheng
2012-01-01
Background It is well known that familial sick sinus syndrome (SSS) is caused by functional alterations of ion channels and gap junction. Limited information is available on the mechanism of age-related non-familial SSS. Although evidence shows a close link between arrhythmia and the renin-angiotensin system (RAS), it remains to be determined whether the RAS is involved in the pathogenesis of non-familial SSS. Methods In this study, 113 patients with documented non-familial SSS and 125 controls were screened for angiotensinogen (AGT) and gap junction protein-connexin 40 (Cx40) promoter polymorphisms by gene sequencing, followed by an association study. A luciferase assay was used to determine the transcriptional activity of the promoter polymorphism. The interaction between nuclear factors and the promoter polymorphism was characterized by an electrophoretic mobility shift assay (EMSA). Results Association study showed the Cx40 -44/+71 polymorphisms are not associated with non-familial SSS; however, it indicated that four polymorphic sites at positions -6, -20, -152, and -217 in the AGT promoter are linked to non-familial SSS. Compared to controls, SSS patients had a lower frequency of the G-6A AA genotype (OR 2.88, 95% CI 1.58–5.22, P = 0.001) and a higher frequency of the G allele at -6 position (OR 2.65, 95% CI 1.54–4.57, P = 0.0003). EMSA and luciferase assays confirmed that nucleotide G at position -6 modulates the binding affinity with nuclear factors and yields a lower transcriptional activity than nucleotide A (P<0.01). Conclusion G-6A polymorphism, which modulates the transcriptional activity of the AGT promoter, may contribute to non-familial SSS susceptibility. PMID:22242192
[Electrocardiographic abnormalities in acute olanzapine poisonings].
Ciszowski, Krzysztof; Sein Anand, Jacek
2011-01-01
Olanzapine is an atypical antipsychotic used for many years in the treatment of schizophrenia and bipolar disorder. Poisonings with this medicine can results with cardiotoxic effects in the form of ECG abnormalities. To evaluate the nature and incidence of electrocardiographic abnormalities in patients with acute olanzapine poisoning. 23 adult (mean age 38.4 +/- 15.5 years) patients with acute olanzapine poisoning, including 10 men (30.4 +/- 8.1 years) and 11 women (45.7 +/- 17.2 years), where 1 man and 1 woman were poisoned twice. The toxic serum level of olanzapine (above 100 ng/mL) was confirmed in each patient. Evaluation of electrocardiograms performed in patients in the first day of hospitalization with automatic measurement of durations of PQ, QRS and QTc and the identification of arrhythmias and conduction disorders on the basis of visual analysis of the ECG waveforms. Statistical analysis of the results using the methods of descriptive statistics. The mean durations of PQ, QRS and QTc in the study group were as follows: 135 +/- 23 ms, 91 +/- 12 ms, and 453 +/- 48 ms, respectively. The most common ECG abnormalities were prolonged QTc and supraventricular tachycardia (including sinus tachycardia) - each 22%; less common were ST-T changes (17%) and supraventricular premature complexes (9%), and only in individual cases (4%) ventricular premature complexes, bundle branch block, sinus bradycardia and atrial fibrillation were present. In the course of acute olanzapine poisonings: (1) prolonged QTc interval is quite common, but rarely leads to torsade de pointes tachycardia; (2) fast supraventricular rhythms are also common, but rarely cause irregular tachyarrhythmias, eg. atrial fibrillation; (3) conduction disorders (atrioventricular blocks, bundle branch blocks) are not typical abnormalities; (4) the observed ECG abnormalities emphasize the need of continuous ECG monitoring in these patients.
Complications of pacemaker therapy in adults with congenital heart disease: a multicenter study.
Opić, Petra; van Kranenburg, Matthijs; Yap, Sing-Chien; van Dijk, Arie P; Budts, Werner; Vliegen, Hubert W; van Erven, Lieselot; Can, Anil; Sahin, Gulhan; Theuns, Dominic A M J; Witsenburg, Maarten; Roos-Hesselink, Jolien W
2013-10-09
This study aims to investigate indications and complications of permanent cardiac pacing in adults with congenital heart disease (CHD). Two-hundred and seventy-four CHD patients were identified who underwent permanent pacemaker implantation between 1972 and 2009. The indication for pacing was acquired sinus node or AV node conduction disease (63%), sinus node or AV node conduction disease after cardiac surgery (28%), and drug/arrhythmia-related indications (9%). Patients with complex CHD received a pacemaker at younger age (23 versus 31 years, p<0.0001) and more often received an epicardial pacing system (51% versus 23%, p<0.0001) compared to those with simple or moderate CHD. Twenty-nine patients (10.6%) had a periprocedural complication during the primary pacemaker implantation (general population: 5.2%). The most common acute complications were lead dysfunction (4.0%), bleeding (2.6%), pocket infection (1.5%) and pneumothorax (1.5%). During a median follow-up of 12 years, pacemaker-related complications requiring intervention occurred in 95 patients (34.6%). The most common late pacemaker-related complications included lead failure (24.8%), pacemaker dysfunction/early battery depletion (5.1%), pacemaker migration (4.7%) and erosion (4.7%). Pacemaker implantation at younger age (<18 years) was an independent predictor of late pacemaker-related complication (adjusted hazard ratio 1.68, 95% confidence interval 1.07 to 2.63, p=0.023). The risk of periprocedural complications seems higher in the CHD population compared to the general population and more than one-third of CHD patients encountered a pacemaker-related complication during long-term follow-up. This risk increases for those who receive a pacemaker at younger age. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.
Madhavan, Malini; Venkatachalam, K. L.; Swale, Matthew J.; DeSimone, Christopher V.; Gard, Joseph J.; Johnson, Susan B.; Suddendorf, Scott H.; Mikell, Susan B.; Ladewig, Dorothy J.; Nosbush, Toni Grabinger; Danielsen, Andrew J.; Knudson, Mark; Asirvatham, Samuel J.
2016-01-01
Background Endocardial ablation of atrial ganglionated plexi (GP) has been described for treatment of atrial fibrillation (AF). Our objective in this study was to develop percutaneous epicardial GP ablation in a canine model using novel energy sources and catheters. Methods Phase 1: The efficacy of several modalities to ablate the GP was tested in an open chest canine model (n=10). Phase 2: Percutaneous epicardial ablation of GP was done in 6 dogs using the most efficacious modality identified in phase 1 using 2 novel catheters. Results Phase 1: DC in varying doses [blocking (7 -12μA), electroporation (300-500μA), ablation (3000- 7500μA)], radiofrequency ablation (25–50 W), ultrasound (1.5MHz), and alcohol (2-5ml) injection were successful at 0/8, 4/12, 5/7, 3/8, 1/5 and 5/7 GP sites. DC (500–5000μA) along with alcohol irrigation was tested in phase 2. Phase 2: Percutaneous epicardial ablation of the right atrium, oblique sinus, vein of Marshall, and transverse sinus GP was successful in 5/6 dogs. One dog died of ventricular fibrillation (VF) during DC ablation at 5000 μA. Programmed stimulation induced AF in 6 dogs pre-ablation and no atrial arrhythmia in 3, flutter in 1 and AF in 1 post-ablation. Heart rate, blood pressure, effective atrial refractory period and local atrial electrogram amplitude did not change significantly post-ablation. Microscopic examination showed elimination of GP, and minimal injury to atrial myocardium. Conclusion Percutaneous epicardial ablation of GP using direct current and novel catheters is safe and feasible and may be used as an adjunct to pulmonary vein isolation in the treatment of atrial fibrillation in order to minimize additional atrial myocardial ablation. PMID:26854009
Tribulova, Narcis; Seki, Shingo; Radosinska, Jana; Kaplan, Peter; Babusikova, Eva; Knezl, Vladimir; Mochizuki, Seibu
2009-12-01
Using whole-heart preparations, we tested our hypothesis that Ca(2+) handling is closely related to cell-to-cell coupling at the gap junctions and that both are critical for the development and particularly the termination of ventricular fibrillation (VF) and hence the prevention of sudden arrhythmic death. Intracellular free calcium concentration ([Ca(2+)](i)), ECG, and left ventricular pressure were continuously monitored in isolated guinea pig hearts before and during development of low K(+)-induced sustained VF and during its conversion into sinus rhythm facilitated by stobadine. We also examined myocardial ultrastructure to detect cell-to-cell coupling alterations. We demonstrated that VF occurrence was preceded by a 55.9% +/- 6.2% increase in diastolic [Ca(2+)](i), which was associated with subcellular alterations indicating Ca(2+) overload of the cardiomyocytes and disorders in coupling among the cells. Moreover, VF itself further increased [Ca(2+)](i) by 58.2% +/- 3.4% and deteriorated subcellular and cell-to-cell coupling abnormalities that were heterogeneously distributed throughout the myocardium. In contrast, termination of VF and its conversion into sinus rhythm was marked by restoration of basal [Ca(2+)](i), resulting in recovery of intercellular coupling linked with synchronous contraction. Furthermore, we have shown that hearts exhibiting lower SERCA2a (sarcoplasmic reticulum Ca(2+)-ATPase) activity and abnormal intercellular coupling (as in older guinea pigs) are more prone to develop Ca(2+) overload associated with cell-to-cell uncoupling than hearts with higher SERCA2a activity (as in young guinea pigs). Consequently, young animals are better able to terminate VF spontaneously. These findings indicate the crucial role of Ca(2+) handling in relation to cell-to-cell coupling in both the occurrence and termination of malignant arrhythmia.
Weiss, Eric H.; Merchant, Faisal M.; d’Avila, Andre; Foley, Lori; Reddy, Vivek Y.; Singh, Jagmeet P.; Mela, Theofanie; Ruskin, Jeremy N.; Armoundas, Antonis A.
2011-01-01
Background Electrical alternans is a pattern of variation in the shape of electrocardiographic waveform that occurs every other beat. In humans, alternation in ventricular repolarization, known as repolarization alternans (RA), has been associated with increased vulnerability to ventricular tachycardia/fibrillation and sudden cardiac death. Methods and Results This study investigates the spatio-temporal variability of intracardiac RA and its relationship to body surface RA in an acute myocardial ischemia model in swine. We developed a real-time multi-channel repolarization signal acquisition, display and analysis system to record electrocardiographic signals from catheters in the right ventricle, coronary sinus, left ventricle, and epicardial surface prior to and following circumflex coronary artery balloon occlusion. We found that RA is detectable within 4 minutes following the onset ischemia, and is most prominently seen during the first half of the repolarization interval. Ischemia-induced RA was detectable on unipolar and bipolar leads (both in near- and far-field configurations) and on body surface leads. Far-field bipolar intracardiac leads were more sensitive for RA detection than body surface leads, with the probability of body surface RA detection increasing as the number of intracardiac leads detecting RA increased, approaching 100% when at least three intracardiac leads detected RA. We developed a novel, clinically-applicable intracardiac lead system based on a triangular arrangement of leads spanning the right ventricular (RV) and coronary sinus (CS) catheters which provided the highest sensitivity for intracardiac RA detection when compared to any other far-field bipolar sensing configurations (p < 0.0001). Conclusions In conclusion, intracardiac alternans, a complex spatio-temporal phenomenon associated with arrhythmia susceptibility and sudden cardiac death, can be reliably detected through a novel triangular RV-CS lead configuration. PMID:21430127
Cardiotoxicity of Freon among refrigeration services workers: comparative cross-sectional study
2009-01-01
Background Freon includes a number of gaseous, colorless chlorofluorocarbons. Although freon is generally considered to be a fluorocarbon of relatively low toxicity; significantly detrimental effects may occur upon over exposure. The purpose of the present study is to investigate whether occupational exposure to fluorocarbons can induce arterial hypertension, myocardial ischemia, cardiac arrhythmias, elevated levels of plasma lipids and renal dysfunction. Methods This comparative cross-sectional study was conducted at the cardiology clinic of the Suez Canal Authority Hospital (Egypt). The study included 23 apparently healthy male workers at the refrigeration services workshop who were exposed to fluorocarbons (FC 12 and FC 22) and 23 likewise apparently healthy male workers (unexposed), the control group. All the participants were interviewed using a pre-composed questionnaire and were subjected to a clinical examination and relevant laboratory investigations. Results There were no significant statistical differences between the groups studied regarding symptoms suggesting arterial hypertension and renal affection, although a significantly higher percentage of the studied refrigeration services workers had symptoms of arrhythmias. None of the workers had symptoms suggesting coronary artery disease. Clinical examination revealed that the refrigeration services workers had a significantly higher mean pulse rate compared to the controls, though no significant statistical differences were found in arterial blood pressure measurements between the two study groups. Exercise stress testing of the workers studied revealed normal heart reaction to the increased need for oxygen, while sinus tachycardia was detected in all the participants. The results of Holter monitoring revealed significant differences within subject and group regarding the number of abnormal beats detected throughout the day of monitoring (p < 0.001). There were no significant differences detected in the average heart rate during the monitoring period within subject or group. Most laboratory investigations revealed absence of significant statistical differences for lipid profile markers, serum electrolyte levels and glomerular lesion markers between the groups except for cholesterol and urinary β2-microglobulin (tubular lesion markers) levels which were significantly elevated in freon exposed workers. Conclusions Unprotected occupational exposure to chlorofluorocarbons can induce cardiotoxicity in the form of cardiac arrhythmias. The role of chlorofluorocarbons in inducing arterial hypertension and coronary artery diseases is unclear, although significantly elevated serum cholesterol and urinary β2-microglobulin levels raise a concern. PMID:19594908
NASA Technical Reports Server (NTRS)
Mullen, T. J.; Appel, M. L.; Mukkamala, R.; Mathias, J. M.; Cohen, R. J.
1997-01-01
We applied system identification to the analysis of fluctuations in heart rate (HR), arterial blood pressure (ABP), and instantaneous lung volume (ILV) to characterize quantitatively the physiological mechanisms responsible for the couplings between these variables. We characterized two autonomically mediated coupling mechanisms [the heart rate baroreflex (HR baroreflex) and respiratory sinus arrhythmia (ILV-HR)] and two mechanically mediated coupling mechanisms [the blood pressure wavelet generated with each cardiac contraction (circulatory mechanics) and the direct mechanical effects of respiration on blood pressure (ILV-->ABP)]. We evaluated the method in humans studied in the supine and standing postures under control conditions and under conditions of beta-sympathetic and parasympathetic pharmacological blockades. Combined beta-sympathetic and parasympathetic blockade abolished the autonomically mediated couplings while preserving the mechanically mediated coupling. Selective autonomic blockade and postural changes also altered the couplings in a manner consistent with known physiological mechanisms. System identification is an "inverse-modeling" technique that provides a means for creating a closed-loop model of cardiovascular regulation for an individual subject without altering the underlying physiological control mechanisms.
Emotion suppression moderates the quadratic association between RSA and executive function.
Spangler, Derek P; Bell, Martha Ann; Deater-Deckard, Kirby
2015-09-01
There is uncertainty about whether respiratory sinus arrhythmia (RSA), a cardiac marker of adaptive emotion regulation, is involved in relatively low or high executive function performance. In the present study, we investigated (a) whether RSA during rest and tasks predict both relatively low and high executive function within a larger quadratic association among the two variables, and (b) the extent to which this quadratic trend was moderated by individual differences in emotion regulation. To achieve these aims, a sample of ethnically and socioeconomically diverse women self-reported reappraisal and emotion suppression. They next experienced a 2-min resting period during which electrocardiogram (ECG) was continually assessed. In the next phase, the women completed an array of executive function and nonexecutive cognitive tasks while ECG was measured throughout. As anticipated, resting RSA showed a quadratic association with executive function that was strongest for high suppression. These results suggest that relatively high resting RSA may predict poor executive function ability when emotion regulation consumes executive control resources needed for ongoing cognitive performance. © 2015 Society for Psychophysiological Research.
Ward, Anthony R; Alarcón, Gabriela; Nigg, Joel T; Musser, Erica D
2015-11-01
Although attention deficit/hyperactivity disorder (ADHD) is associated with impairment in working memory and short-term memory, up to half of individual children with ADHD perform within a normative range. Heterogeneity in other ADHD-related mechanisms, which may compensate for or combine with cognitive weaknesses, is a likely explanation. One candidate is the robustness of parasympathetic regulation (as indexed by respiratory sinus arrhythmia; RSA). Theory and data suggest that a common neural network is likely tied to both heart-rate regulation and certain cognitive functions (including aspects of working and short-term memory). Cardiac-derived indices of parasympathetic reactivity were collected during short-term memory (STM) storage and rehearsal tasks from 243 children (116 ADHD, 127 controls). ADHD was associated with lower STM performance, replicating previous work. In addition, RSA reactivity moderated the association between STM and ADHD - both as a category and a dimension - independent of comorbidity. Specifically, conditional effects revealed that high levels of withdrawal interacted with weakened STM but high levels of augmentation moderated a positive association predicting ADHD. Thus, variations in parasympathetic reactivity may help explain neuropsychological heterogeneity in ADHD.
Whooping Cough in Adults: A Series of Severe Cases.
Zycinska, K; Cieplak, M; Chmielewska, M; Nitsch-Osuch, A; Klaczkow, A; Hadzik-Blaszczyk, M; Kur, Z; Wardyn, K A
2017-01-01
Bordetella pertussis is a gram-negative aerobic coccobacillus causing contagious respiratory tract disease called whooping cough. The virulence factors consist of pertussis toxin, filamentous hemagglutinin, fimbriae, lipooligosaccharide, and adenylate cyclase toxin. The disease causes a worldwide threat to public health despite a high vaccination coverage. The course of whooping cough in adults is frequently atypical, causing difficulty in diagnosis. In this report we present five patients hospitalized with Bordetella pertussis infection manifesting atypical and severe symptoms. The diagnosis was based on serological tests: serum concentration of specific antibodies against pertussis toxin and sputum cultures. We observed a wide spectrum of symptoms, from benign (sinus pain - 80 %, headaches - 20 %), through moderate (hemoptysis - 40 %; chest pain 60 %) to severe symptoms (cardiac arrhythmia - 40 %; syncope - 60 %). Bordetella pertussis infection can cause life-threatening complications and exacerbation of concomitant chronic diseases. Most vaccination programs cover only the first few months of life. Booster doses should be considered in adults, especially those immunocompromised or with pulmonary complications, but also in healthcare workers who are exposed to the contagion and also may spread the infection.
Provenzi, Livio; Casini, Erica; de Simone, Paola; Reni, Gianluigi; Borgatti, Renato; Montirosso, Rosario
2015-12-01
Infants' social stress regulation (i.e., reactivity and recovery) might be affected by mother-infant dyadic functioning and infants' vagal tone (i.e., respiratory sinus arrhythmia, RSA). This study investigated the role of a specific dyadic functioning feature (i.e., dyadic reparation) and individual differences in vagal tone regulation (i.e., RSA suppression vs. non-suppression) in relation to social stress regulation in 4-month-old infants. A total of 65 mother-infant dyads participated in the face-to-face still-face paradigm. Social stress reactivity and recovery were measured as negative emotionality during Still-Face and Reunion episodes, respectively. RSA was measured during Play, Still-Face, and Reunion episodes. Suppressors had higher dyadic reparation during Play and higher recovery from social stress compared with non-suppressors. Higher reparation during Play was associated with lower reactivity and higher recovery only for suppressors. Findings suggest a joint role of infants' RSA individual differences and dyadic reparation in affecting infants' social stress regulation at 4 months of age. Copyright © 2015 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Baevsky, R. M.; Bennett, B. S.; Bungo, M. W.; Charles, J. B.; Goldberger, A. L.; Nikulina, G. A.
1997-01-01
This article presents selected findings obtained with Holter monitoring from two crew members of the expedition, performed during a 175-day space mission on board orbital space station "MIR." Using mathematical processing of daily cardiointervals files, 5-minute sections of records were analyzed consecutively. Then, the average daily values of indices, the average-per-every-eight-hours values (morning, evening, night) and mean values per hour were computed. The results of analysis showed that prolonged exposure of man to microgravity conditions leads to important functional alteration in human neuroautonomic regulatory mechanisms. Both crew members had significant increase of heart rate, the rise of stress index, the decrease in power of the spectrum in the range of respiratory sinus arrhythmia. These marked signs of activation of the sympathetic section of the vegetative nervous system showed individual variations. The analysis of the daily collection of cardiointervals with Holter monitoring allows us to understand and forecast the functional feasibilities of the human organism under a variety of stress conditions associated with acute and chronic microgravity exposure.
Wilhelm, Frank H; Rattel, Julina A; Wegerer, Melanie; Liedlgruber, Michael; Schweighofer, Simon; Kreibig, Sylvia D; Kolodyazhniy, Vitaliy; Blechert, Jens
2017-12-01
Sex differences in emotional reactivity have been studied primarily for negative but less so for positive stimuli; likewise, sex differences in the psychophysiological response-patterning during such stimuli are poorly understood. Thus, the present study examined sex differences in response to negative/positive and high/low arousing films (classified as threat-, loss-, achievement-, and recreation-related, vs. neutral films), while measuring 18 muscular, autonomic, and respiratory parameters. Sex differences emerged for all films, but were most prominent for threat-related films: Despite equivalent valence and arousal ratings, women displayed more facial-muscular and respiratory responding than men and pronounced sympathetic activation (preejection period, other cardiovascular and electrodermal measures), while men showed coactivated sympathetic/parasympathetic responding (including increased respiratory sinus arrhythmia). This indicates a prototypical threat-related defense response in women, while men showed a pattern of sustained orienting, which can be understood as a shift toward less threat proximity in the defense cascade model. Clinical implications are discussed within a socio-evolutionary framework. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Uijtdehaage, S. H.; Stern, R. M.; Koch, K. L.
1992-01-01
This study investigated the effect of food ingestion on motion sickness severity and its physiological mechanisms. Forty-six fasted subjects were assigned either to a meal group or to a no-meal group. Electrogastrographic (EGG) indices (normal 3 cpm activity and abnormal 4-9 cpm tachyarrhythmia) and respiratory sinus arrhythmia (RSA) were measured before and after a meal and during a subsequent exposure to a rotating drum in which illusory self-motion was induced. The results indicated that food intake enhanced cardiac parasympathetic tone (RSA) and increased gastric 3 cpm activity. Postprandial effects on motion sickness severity remain equivocal due to group differences in RSA baseline levels. During drum rotation, dysrhythmic activity of the stomach (tachyarrhythmia) and vagal withdrawal were observed. Furthermore, high levels of vagal tone prior to drum rotation predicted a low incidence of motion sickness symptoms, and were associated positively with gastric 3 cpm activity and negatively with tachyarrhythmia. These data suggest that enhanced levels of parasympathetic activity can alleviate motion sickness symptoms by suppressing, in part, its dysrhythmic gastric underpinnings.
Effects of scopolamine on autonomic profiles underlying motion sickness susceptibility
NASA Technical Reports Server (NTRS)
Uijtdehaage, Sebastian H. J.; Stern, Robert M.; Koch, Kenneth L.
1993-01-01
The purpose of this study was to examine the effects of scopolamine on the physiological patterns occurring prior to and during motion sickness stimulation. In addition, the use of physiological profiles in the prediction of motion sickness was evaluated. Sixty subjects ingested either 0.6 mg scopolamine, 2.5 mg methoscopolamine, or a placebo. Heart rate (HR), respiratory sinus arrhythmia (an index of vagal tone), and electrogastrograms were measured prior to and during the exposure to a rotating optokinetic drum. Compared to the other groups, the scopolamine group reported fewer motion sickness symptoms, and displayed lower HR, higher vagal tone, enhanced normal gastric myoelectric activity, and depressed gastric dysrhythmias before and during motion sickness induction. Distinct physiological profiles prior to drum rotation could reliably differentiate individuals who would develop gastric discomfort from those who would not. Symptom-free subjects were characterized by high levels of vagal tone and low HR across conditions, and by maintaining normal (3 cpm) electrogastrographic activity during drum rotation. It was concluded that scopolamine offered motion sickness protection by initiating a pattern of increased vagal tone and gastric myoelectric stability.
Sleeper, M M; Kusiak, C M; Shofer, F S; O'Donnell, P; Bryan, C; Ponder, K P; Haskins, M E
2008-06-01
The purpose of this study was to define the cardiovascular abnormalities present in young and adult cats affected with the lysosomal storage diseases mucopolysaccharidosis (MPS) I and MPS VI. Eighteen cats affected with MPS I and 10 cats affected with MPS VI were evaluated by physical examination, electrocardiography and echocardiography. Electrocardiography (ECG) was performed on all MPS I and 9 of the MPS VI cats. Twelve unaffected cats underwent complete examinations for comparison purposes. No cardiovascular abnormalities were noted on physical examination. Measured ECG intervals were normal in affected cats; however, sinus arrhythmia was noted more frequently than in the unaffected cats. Significant echocardiographic abnormalities included aortic valve thickening, regurgitation and aortic root dilation. Significant mitral valve thickening was also noted. The severity of changes increased in older affected cats. As affected animals increased in age, more cardiac abnormalities were found with increasing severity. Significant lesions included the mitral and aortic valves and ascending aorta, but myocardial changes were not recognized. MPS I and MPS VI cats have similar cardiovascular findings to those seen in children and constitute important models for testing new MPS therapies.
Edla, Shwetha; Kovvali, Narayan; Papandreou-Suppappola, Antonia
2012-01-01
Constructing statistical models of electrocardiogram (ECG) signals, whose parameters can be used for automated disease classification, is of great importance in precluding manual annotation and providing prompt diagnosis of cardiac diseases. ECG signals consist of several segments with different morphologies (namely the P wave, QRS complex and the T wave) in a single heart beat, which can vary across individuals and diseases. Also, existing statistical ECG models exhibit a reliance upon obtaining a priori information from the ECG data by using preprocessing algorithms to initialize the filter parameters, or to define the user-specified model parameters. In this paper, we propose an ECG modeling technique using the sequential Markov chain Monte Carlo (SMCMC) filter that can perform simultaneous model selection, by adaptively choosing from different representations depending upon the nature of the data. Our results demonstrate the ability of the algorithm to track various types of ECG morphologies, including intermittently occurring ECG beats. In addition, we use the estimated model parameters as the feature set to classify between ECG signals with normal sinus rhythm and four different types of arrhythmia.
Holt-Lunstad, Julianne; Uchino, Bert N; Smith, Timothy W; Hicks, Angela
2007-06-01
Social relationships are reliably related to rates of morbidity and mortality. One pathway by which social relationships may influence health is via the impact of relationship quality on cardiovascular reactivity during social interactions. This study examined the effects of the quality of a friendship on cardiovascular reactivity when speaking about positive or negative life events with an ambivalent or supportive friend. To examine this, 107 healthy male and female adults (and their same-sex friend) were recruited. Results revealed that participants exhibited the greatest levels of systolic blood pressure reactivity when discussing a negative event with an ambivalent friend compared to a supportive friend. We also found higher resting levels of heart rate and lower respiratory sinus arrhythmia among those who brought in ambivalent friends than those who brought in supportive friends. Individuals may not be able to fully relax in the presence of ambivalent friends and may not benefit from support during stress. This research may help clarify the health-related consequences of differing types of social relationships.
Cooper-Vince, Christine E.; DeSerisy, Mariah; Cornacchio, Danielle; Sanchez, Amanda; McLaughlin, Katie A.; Comer, Jonathan S.
2017-01-01
Parasympathetic nervous system influences on cardiac functions—commonly indexed via respiratory sinus arrhythmia (RSA)—are central to self-regulation. RSA suppression during challenging emotional and cognitive tasks is often associated with better emotional and behavioral functioning in preschoolers. However, the links between RSA suppression and child behavior across various challenging interpersonal contexts remains unclear. The present study experimentally evaluated the relationship between child RSA reactivity to adult (mother vs. study staff) direction and disruptive behavior problems in children ages 3–8 with varying levels of disruptive behavior problems (N=43). Reduced RSA suppression in the context of mothers’ play-based direction was associated with more severe child behavior problems. In contrast, RSA suppression in the context of staff play-based direction was not associated with behavior problems. Findings suggest that the association between RSA suppression and child behavior problems may vary by social context (i.e., mother vs. other adult direction-givers). Findings are discussed in regard to RSA as an indicator of autonomic self-regulation that has relevance to child disruptive behavior problems. PMID:28261792
Ravaja, Niklas; Kallinen, Kari
2004-07-01
We examined the moderating influence of dispositional behavioral inhibition system (BIS) and behavioral activation system (BAS) sensitivities on the relationship of startling background music with emotion-related subjective and physiological responses elicited during reading news reports, and with memory performance among 26 adult men and women. Physiological parameters measured were respiratory sinus arrhythmia (RSA), electrodermal activity (EDA), and facial electromyography (EMG). The results showed that, among high BAS individuals, news stories with startling background music were rated as more interesting and elicited higher zygomatic EMG activity and RSA than news stories with non-startling music. Among low BAS individuals, news stories with startling background music were rated as less pleasant and more arousing and prompted higher EDA. No BIS-related effects or effects on memory were found. Startling background music may have adverse (e.g., negative arousal) or beneficial effects (e.g., a positive emotional state and stronger positive engagement) depending on dispositional BAS sensitivity of an individual. Actual or potential applications of this research include the personalization of media presentations when using modern media and communications technologies.
McQuade, Julia D; Breaux, Rosanna P
2017-12-01
This study examined whether measures of children's autonomic nervous system (ANS) reactivity to social stress moderated the effect of parent emotion socialization on children's social and emotional adjustment. Sixty-one children (9-13 years) completed a peer rejection task while their respiratory sinus arrhythmia reactivity (RSA-R) and skin conductance level reactivity (SCL-R) were assessed. Parents' report of supportive and non-supportive reactions to their child's negative emotions served as measures of emotion socialization. Measures of children's social and emotional adjustment included: teacher-rated peer rejection, aggression, and prosocial behavior and parent-rated aggressive/dysregulated behavior and emotion regulation skills. Measures of children's ANS reactivity moderated the effect of parent emotion socialization on children's adjustment. Supportive responses were more protective for children evidencing RSA augmentation whereas non-supportive responses were more detrimental for children evidencing low SCL-R. Thus children's ANS reactivity during social stress may represent a biological vulnerability that influences sensitivity to parent emotion socialization. Copyright © 2017 Elsevier B.V. All rights reserved.
Contingency Learning and Reactivity in Preterm and Full-Term Infants at 3 Months
Haley, David W.; Grunau, Ruth E.; Oberlander, Tim F.; Weinberg, Joanne
2010-01-01
Learning difficulties in preterm infants are thought to reflect impairment in arousal regulation. We examined relationships among gestational age, learning speed, and behavioral and physiological reactivity in 55 preterm and 49 full-term infants during baseline, contingency, and nonreinforcement phases of a conjugate mobile paradigm at 3 months corrected age. For all infants, negative affect, looking duration, and heart rate levels increased during contingency and nonreinforcement phases, whereas respiratory sinus arrhythmia (RSA, an index of parasympathetic activity) decreased and cortisol did not change. Learners showed greater RSA suppression and less negative affect than nonlearners. This pattern was particularly evident in the preterm group. Overall, preterm infants showed less learning, spent less time looking at the mobile, and had lower cortisol levels than full-term infants. Preterm infants also showed greater heart rate responses to contingency and dampened heart rate responses to nonreinforcement compared to full-term infants. Findings underscore differences in basal and reactivity measures in preterm compared to full-term infants and suggest that the capacity to regulate parasympathetic activity during a challenge enhances learning in preterm infants. PMID:20717491
Early plasma exchange for treating ricin toxicity in children after castor bean ingestion.
Wang, Cheng-feng; Nie, Xiao-jing; Chen, Guang-ming; Yu, Zi-hua; Li, Zheng; Sun, Zhi-wen; Weng, Zeng-feng; Yang, Yu-ying; Chen, Shu-lian; Zheng, Si-rui; Luo, Ying-yun; Lu, Yan-ting; Cao, Hui-qin; Zhan, Hai-xia
2015-06-01
Plasma exchange (PE) for the treatment of ricin toxicity has not been previously reported. Here we describe the use of PE to treat children who experienced ricin toxicity after ingesting castor beans. Seven children (median age: 8.1 years) who consumed castor beans (median: 5 beans) were treated with PE. All had bradycardia and sinus arrhythmia, and most had experienced episodes of vomiting and/or diarrhea. PE settings were blood flow, 50-80 mL/min; PE rate, 600-800 mL/h; volume of exchange, 1440-1950 mL. Median time from ingestion to PE was 73 h. All clinical symptoms disappeared and vital signs rapidly returned to normal after PE; no severe organ dysfunction occurred. All children were discharged and recovered uneventfully. Concentrations of all serum biochemical parameters significantly decreased immediately after PE. Some, but not all, of these parameters were also significantly decreased at 48 and 72 h after PE compared with before PE. Our findings suggest that PE can be an effective early intervention in the treatment of ricin toxicity due to castor bean ingestion. © 2014 Wiley Periodicals, Inc.
Holterman, Leigh Ann; Murray-Close, Dianna K; Breslend, Nicole L
2016-12-01
The goal of the current study was to investigate the association between relational victimization, defined as being the target of aggressive acts that damage relationships (e.g., gossip, social exclusion) and depressive symptoms during the relatively understudied developmental period of emerging adulthood. In addition, as individual differences in stress reactivity may influence the outcomes associated with victimization by peers, the moderating roles of sympathetic nervous system (SNS; as measured by skin conductance reactivity) and parasympathetic nervous system (PNS; as measured by respiratory sinus arrhythmia) reactivity to social and non-social stressors were examined. Findings indicated that relational victimization was positively related to depressive symptoms in individuals demonstrating coactivation (i.e., high SNS and PNS reactivity) and coinhibition (blunted SNS and PNS reactivity) to both social and non-social stressor tasks. These patterns may reflect a breakdown of regulation in the body's physiological response to stress, thus increasing risk for depressive symptoms in the context of peer stress. Findings highlight potential areas for future interventions. Copyright © 2016 Elsevier B.V. All rights reserved.
Portable electrocardiograph through android application.
De Oliveira, Igor H; Cene, V H; Balbinot, A
2015-01-01
An electrocardiograph was designed and implemented, being capable of obtaining electrical signals from the heart, and sending this data via Bluetooth to a tablet, in which the signals are graphically shown. The user interface is developed as an Android application. Because of the technological progress and the increasing use of full portable systems, such as tablets and cell phones, it is important to understand the functioning and development of an application, which provides a basis for conducting studies using this technology as an interface. The project development includes concepts of electronics and its application to achieve a portable and functional final project, besides using a specific programmable integrated circuit for electrocardiogram, electroencephalogram and electromyogram, the ADS1294. Using a simulator of cardiac signals, 36 different waveforms were recorded, including normal sinus rhythm, arrhythmias and artifacts. Simulations include variations of heart rate from 30 to 190 beats per minute (BPM), with variations in peak amplitude of 1 mV to 2 mV. Tests were performed with a subject at rest and in motion, observing the signals obtained and the damage to their interpretation due to the introduction of muscle movement artifacts in motion situations.
Crowell, Sheila E.; Baucom, Brian R.; Yaptangco, Mona; Bride, Daniel; Hsiao, Ray; McCauley, Elizabeth; Beauchaine, Theodore P.
2014-01-01
Many depressed adolescents experience difficulty regulating their emotions. These emotion regulation difficulties appear to emerge in part from socialization processes within families and then generalize to other contexts. However, emotion dysregulation is typically assessed within the individual, rather than in the social relationships that shape and maintain dysregulation. In this study, we evaluated concordance of physiological and observational measures of emotion dysregulation during interpersonal conflict, using a multilevel actor-partner interdependence model (APIM). Participants were 75 mother-daughter dyads, including 50 depressed adolescents with or without a history of self-injury, and 25 typically developing controls. Behavior dysregulation was operationalized as observed aversiveness during a conflict discussion, and physiological dysregulation was indexed by respiratory sinus arrhythmia (RSA). Results revealed different patterns of concordance for control versus depressed participants. Controls evidenced a concordant partner (between-person) effect, and showed increased physiological regulation during minutes when their partner was more aversive. In contrast, clinical dyad members displayed a concordant actor (within-person) effect, becoming simultaneously physiologically and behaviorally dysregulated. Results inform current understanding of emotion dysregulation across multiple levels of analysis. PMID:24607894
Gianaros, Peter J.; Stern, Robert M.; Morrow, Gary R.; Hickok, Jane T.
2010-01-01
Objectives We evaluated (a) whether pretreatment levels of gastric tachyarrhythmia, a dysrhythmic pattern of gastric myoelectrical activity, or cardiac parasympathetic activity are associated with the development of chemotherapy-induced nausea and (b) whether chemotherapy-induced nausea is preceded by an increase in gastric tachyarrhythmia and a decrease in cardiac parasympathetic activity, as has been observed during motion sickness. Methods Electrogastrograms and estimates of respiratory sinus arrhythmia (RSA) were obtained from cancer chemotherapy patients before treatment and for approximately 24 hours after treatment. Results Higher levels of pretreatment gastric tachyarrhythmia were observed on chemotherapy sessions that were followed by posttreatment reports of nausea. Pretreatment levels of RSA, however, did not differ between chemotherapy treatments that were and were not followed by nausea. No statistically significant changes in gastric tachyarrhythmia or RSA were observed prior to first reports of nausea following chemotherapy. Conclusions In contrast to motion sickness, chemotherapy-induced nausea may not be related to an increase in dysrhythmic gastric myoelectrical activity; however, higher levels of pretreatment gastric tachyarrhythmia may be related to posttreatment reports of chemotherapy-induced nausea. PMID:11399283
Chapman, H A; Woltering, S; Lamm, C; Lewis, M D
2010-05-01
Emotional reactions involve changes in both cognitive and bodily processes. Therefore, effective emotion regulation may also involve modulation of responses in both of these systems. The present study investigated the relationship between regulation of cognition and regulation of the heart in children and adolescents, using a go/nogo task in combination with the induction of negative emotions. Behavioral, temperamental and event-related brain potential (ERP) indicators of inhibitory cognitive control were collected, as was a measure of parasympathetic control of the heart (respiratory sinus arrhythmia, RSA). Independently of age, RSA was correlated with nogo N2 magnitudes during the emotion-induction procedure. RSA during the task was also correlated with N2 latencies and with behavioral accuracy before, during and after the emotion induction. Resting RSA was correlated with individual differences in the capacity for effortful cognitive control, as measured by questionnaire. These results suggest that emotional responses in seemingly distinct neurophysiological systems may be regulated in an integrated fashion throughout the developmental span tested. Copyright 2010 Elsevier B.V. All rights reserved.
Developmental origins of infant stress reactivity profiles: A multi-system approach.
Rash, Joshua A; Thomas, Jenna C; Campbell, Tavis S; Letourneau, Nicole; Granger, Douglas A; Giesbrecht, Gerald F
2016-07-01
This study tested the hypothesis that maternal physiological and psychological variables during pregnancy discriminate between theoretically informed infant stress reactivity profiles. The sample comprised 254 women and their infants. Maternal mood, salivary cortisol, respiratory sinus arrhythmia (RSA), and salivary α-amylase (sAA) were assessed at 15 and 32 weeks gestational age. Infant salivary cortisol, RSA, and sAA reactivity were assessed in response to a structured laboratory frustration task at 6 months of age. Infant responses were used to classify them into stress reactivity profiles using three different classification schemes: hypothalamic-pituitary-adrenal (HPA)-axis, autonomic, and multi-system. Discriminant function analyses evaluated the prenatal variables that best discriminated infant reactivity profiles within each classification scheme. Maternal stress biomarkers, along with self-reported psychological distress during pregnancy, discriminated between infant stress reactivity profiles. These results suggest that maternal psychological and physiological states during pregnancy have broad effects on the development of the infant stress response systems. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 58: 578-599, 2016. © 2016 Wiley Periodicals, Inc.
Depressive Symptoms, Rumination, and Emotion Reactivity Among Youth: Moderation by Gender.
Somers, Jennifer A; Borelli, Jessica L; Hilt, Lori M
2018-06-07
The emotion context-insensitivity hypothesis (ECI; Rottenberg et al., 2005) posits that depressive symptoms are associated with blunted emotional reactivity and is supported by the results of a meta-analysis (Bylsma et al., 2008). Yet it remains unclear how strongly ECI holds across emotional response domains, whether ECI operates similarly in male and female individuals, and whether this pattern of underreactivity is observed in youth. In contrast, rumination, a cognitive style strongly associated with depressive symptoms, may be associated with heightened reactivity. We assessed the effects of youth's depressive symptoms and rumination on subjective and physiological emotion reactivity (N = 160; M age = 12.67, SD age = 1.12; 48% female; 94% non-Hispanic). State sadness and respiratory sinus arrhythmia were assessed during a baseline activity (nature video) and a sad mood induction. As hypothesized, depressive symptoms predicted less subjective emotional reactivity, whereas rumination predicted more subjective reactivity. Exploratory analyses revealed that associations for physiological reactivity differed by child gender. ECI may be stronger in terms of subjective rather than physiological emotional reactivity.
New micro waveforms firstly recorded on electrocardiogram in human.
Liu, Renguang; Chang, Qinghua; Chen, Juan
2015-10-01
In our study, not only the P-QRS-T waves but also the micro-wavelets before QRS complex (in P wave and PR segment) and after QRS complex (ST segment and upstroke of T wave) were first to be identified on surface electrocardiogram in human by the "new electrocardiogram" machine (model PHS-A10) according to conventional 12-lead electrocardiogram connection methods. By comparison to the conventional electrocardiogram in 100 cases of healthy individuals and several patients with arrhythmias, we have found that the wavelets before P wave theoretically reflected electrical activity of sinus node and the micro-wavelets before QRS complex may be related to atrioventricular conduction system (atrioventricular node, His bundle and bundle branch) potentials. Noninvasive atrioventricular node and His bundle potential tracing will contribute to differentiation of the origin of wide QRS and the location of the atrioventricular block. We also have found that the wavelets after QRS complex may be associated with phase 2 and 3 repolarization of ventricular action potential, which will further reveal ventricular repolarization changes. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sauer, Charles W; Marc-Aurele, Krishelle L
2016-07-28
BACKGROUND This is a case of a neonate with susceptibility to long QT syndrome (LQTS) who presented with a sudden unexpected infant death. Experts continue to debate whether universal electrocardiogram (ECG) screening of all newborns is feasible, practical, and cost-effective. CASE REPORT A 19-day-old neonate was found unresponsive by her mother. ECG showed ventricular fibrillation and a combination of a lidocaine drip plus multiple defibrillations converted the rhythm to normal sinus. Unfortunately, MRI brain imaging showed multiple infarcts and EEG showed burst suppression pattern with frequent seizures; life supportive treatment was stopped and the infant died. Genetic testing revealed two mutations in the KCNE2 gene consistent with susceptibility to LQTS type 6. CONCLUSIONS We believe this case is the first to demonstrate both a precipitating electrocardiographic and genetic cause of death for an infant with LQTS, showing a cause-and-effect relationship between LQTS mutation, ventricular arrhythmia, and death. We wonder whether universal ECG newborn screening to prevent LQTS death could have saved this baby.
Factors influencing the role of cardiac autonomic regulation in the service of cognitive control.
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.
Mapping Cardiac Physiology and Parenting Processes in Maltreating Mother–Child Dyads
Skowron, Elizabeth A.; Loke, Eric; Gatzke-Kopp, Lisa M.; Cipriano-Essel, Elizabeth A.; Woehrle, Petra L.; Van Epps, John J.; Gowda, Anjali; Ammerman, Robert T.
2013-01-01
Child maltreatment (CM) lies on an extreme end of the continuum of parenting-at-risk, and while CM has been linked with a variety of behavioral indicators of dysregulation in children, less is known about how physiological markers of regulatory capacity contribute to this association. The present study examined patterns of mother and child physiological regulation and their relations with observed differences in parenting processes during a structured interaction. Abusing, neglecting, and non-CM mothers and their 3- to 5-year-old children completed a resting baseline and moderately challenging joint task. The structural analysis of social behavior was used to code mother–child interactions while simultaneous measures of respiratory sinus arrhythmia were obtained. Results indicated that physically abusive mothers were more likely to react to children’s positive bids for autonomy with strict and hostile control, than either neglecting or non-CM mothers. CM exposure and quality of maternal responding to children’s autonomous bids were uniquely associated with lower parasympathetic tone in children. Results provide evidence of neurodevelopmental associations between early CM exposure, the immediate interactive context of parenting, and children’s autonomic physiology. PMID:21842991
1990-01-01
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Perry, Nicole B.; Nelson, Jackie A.; Swingler, Margaret M.; Leerkes, Esther M.; Calkins, Susan D.; Marcovitch, Stuart; O’Brien, Marion
2017-01-01
Trajectories of baseline RSA (respiratory sinus arrhythmia), an index of reactivity, and vagal withdrawal, an index of regulation, across the preschool period were examined. In addition, maternal emotional support was investigated as a potential time-varying predictor of these trajectories. Physiological measures were obtained during frustration tasks, and a maternal emotional support measure was assessed via maternal report and direct observation. Children’s baseline RSA and vagal withdrawal scores were moderately stable across the preschool period. Growth models indicated that children’s baseline RSA scores changed linearly over the preschool years, and there was significant variability in withdrawal trajectories. Greater maternal emotional support predicted higher initial withdrawal levels and lower emotional support was associated with the greatest increase in withdrawal over time. This suggests that children of higher emotionally supportive mothers reached higher levels of physiological regulation earlier in development and therefore did not show the same increase across preschool as children of less supportive mothers. Maternal emotional support was not significantly related to trajectories of baseline RSA. PMID:22573287
Ravaja, Niklas
2004-01-01
We examined the moderating influence of dispositional behavioral inhibition system and behavioral activation system (BAS) sensitivities, Negative Affect, and Positive Affect on the relationship between a small moving vs. static facial image and autonomic responses when viewing/listening to news messages read by a newscaster among 36 young adults. Autonomic parameters measured were respiratory sinus arrhythmia (RSA), low-frequency (LF) component of heart rate variability (HRV), electrodermal activity, and pulse transit time (PTT). The results showed that dispositional BAS sensitivity, particularly BAS Fun Seeking, and Negative Affect interacted with facial image motion in predicting autonomic nervous system activity. A moving facial image was related to lower RSA and LF component of HRV and shorter PTTs as compared to a static facial image among high BAS individuals. Even a small talking facial image may contribute to sustained attentional engagement among high BAS individuals, given that the BAS directs attention toward the positive cue and a moving social stimulus may act as a positive incentive for high BAS individuals.
Prevalence of atrial arrhythmias in arrhythmogenic right ventricular dysplasia/cardiomyopathy.
Camm, Christian F; James, Cynthia A; Tichnell, Crystal; Murray, Brittney; Bhonsale, Aditya; te Riele, Anneline S J M; Judge, Daniel P; Tandri, Harikrishna; Calkins, Hugh
2013-11-01
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited cardiomyopathy, characterized by right ventricular dysfunction and ventricular arrhythmias. Limited information is available concerning atrial arrhythmias in ARVD/C. The purpose of this study was to characterize spontaneous atrial arrhythmias in a large registry population of ARVD/C patients. Patients (n = 248) from the Johns Hopkins ARVD/C registry who met the diagnostic criteria and had undertaken genotype analysis were included. Medical records of each were reviewed to ascertain incidence and characteristics of atrial arrhythmia episodes. Detailed demographic, phenotypic, and structural information was obtained from registry data. Thirty-five patients with ARVD/C (14%) experienced one or more types of atrial arrhythmia during median follow-up of 5.78 (interquartile range 8.52) years. Atrial fibrillation was the most common atrial arrhythmia, occurring in 80% of ARVD/C patients with atrial arrhythmias. Patients developed atrial arrhythmias at a mean age of 43.0 ± 14.0 years. Atrial arrhythmia patients obtained a total of 22 inappropriate implantable cardioverter-defibrillator shocks during follow-up. Older age at last follow-up (P <.001) and male gender (P = .044) were associated with atrial arrhythmia development. Patients with atrial arrhythmias had a higher occurrence of death (P = .028), heart failure (P <.001), and left atrial enlargement on echocardiography (P = .004). Atrial arrhythmias are common in ARVD/C and present at a younger age than in the general population. They are associated with male gender, increasing age, and left atrial enlargement. Atrial arrhythmias are clinically important as they are associated with inappropriate implantable cardioverter-defibrillator shocks and increased risk of both death and heart failure. © 2013 Heart Rhythm Society. All rights reserved.
Atrial Fibrillation Medications
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Crestal Sinus Augmentation in the Presence of Severe Sinus Mucosal Thickening: A Report of 3 Cases.
Fang, Yiqin; An, Xueyin; Jeong, Seung-Mi; Choi, Byung-Ho
2018-06-01
In the presence of severe sinus mucosal thickening, the ostium can be blocked when the sinus membrane is lifted, causing drainage disturbances and sinusitis. Here, we present 3 cases in which maxillary sinus floor elevation was performed using a crestal approach in the presence of severe sinus mucosal thickening (>10 mm). The effects of maxillary sinus floor elevation using the crestal approach technique on sinus mucosal thickening and bone formation in the sinus were evaluated using cone beam computed tomography. None of the patients exhibited an increase in sinus membrane thickness. No complications were encountered during the follow-up periods, and bone formation was observed around the implants at the sinus floor. All implants were functioning successfully. Maxillary sinus floor elevation using the crestal approach technique in the presence of severe sinus mucosal thickening allows for minimally invasive sinus grafting and simultaneous implant placement and does not increase sinus membrane thickness.
Patient's Guide to Taking Warfarin
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Heart Attack Symptoms in Women
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Understand Your Risk for Heart Failure
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Prevention and Treatment of Arrhythmia
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Single Photon Emission Computed Tomography (SPECT)
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[Radiographic study of maxillary sinus associated with molars in adult].
Hu, Zhi; Sun, Daming; Zhou, Quansheng; Wang, Yuli; Gu, Jingcheng; Han, Yaohua
2014-12-01
to explore the relationship between the maxillary sinus volume and the amount of alveolar bone, and the effect of molar loss upon the maxillary sinus was further analyzed,by measuring adult maxillary sinus volume, sinus ridge distance, and calculating the gasification coefficient of maxillary sinus. One hundred and ninety cases (361 maxillary sinus) with CT examinations were collected, they were divided into group A and group B, 121 cases (242 maxillary sinus) of normal subjects served as group A, 42 cases (65 maxillary sinus) with molar part off were B group, in which 31 maxillary sinus with a molar loss were group B1,22 maxillary sinus with two molar loss were B2 group,12 maxillary sinus with three molar loss (one molar remains) were B3 group, 27 cases (54 maxillary sinus) with upper teeth off were C group. Bymeasureing the maxillary sinus volume, sinus ridge distance and the size of the maxillary sinus, calculating the gasification coefficient, we analyzed the relationship between maxillary volume and sinus ridge distance, and comparatively analyzed the differences among the three groups in the size, gasification coefficient, volume of maxillary sinus and sinus ridge distance. In the normal group,the volume of maxillary sinus and sinus ridge distance had a correlation coefficient of -0. 63,(P< 0.05); Sinus ridge distance in group A was larger than the other two groups (P<0.05), and larger in B group than in C group (P<0. 05), anteroposterior maxillary sinus diameter and reft-right diameter in C group was greater than in A group and B group(P<0.05), group C gasification coeffiecent was less than A group and B group (P<0. 05). The volume of maxillary sinus is negatively correlated with the amont of alveolar bone; Upper teeth's shedding promotes maxillary sinus deformation; Maxiuary sinus volume has a tendency to decrease.
Angina in Women Can Be Different Than Men
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Pacemaker Use Following Heart Transplantation
Mallidi, Hari R.; Bates, Michael
2017-01-01
Background: The incidence of permanent pacemaker implantation after orthotopic heart transplantation has been reported to be 2%-24%. Transplanted hearts usually exhibit sinus rhythm in the operating room following reperfusion, and most patients do not exhibit significant arrhythmias during the postoperative period. However, among the patients who do exhibit abnormalities, pacemakers may be implanted for early sinus node dysfunction but are rarely used after 6 months. Permanent pacing is often required for atrioventricular block. A different cohort of transplant patients presents later with bradycardia requiring pacemaker implantation, reported to occur in approximately 1.5% of patients. The objectives of this study were to investigate the indications for pacemaker implantation, compare the need for pacemakers following bicaval vs biatrial anastomosis, and examine the long-term outcomes of heart transplant patients who received pacemakers. Methods: For this retrospective, case-cohort, single-institution study, patients were identified from clinical research and administrative transplant databases. Information was supplemented with review of the medical records. Standard statistical techniques were used, with chi-square testing for categorical variables and the 2-tailed t test for continuous variables. Survival was compared with the use of log-rank methods. Results: Between January 1968 and February 2008, 1,450 heart transplants were performed at Stanford University. Eighty-four patients (5.8%) were identified as having had a pacemaker implanted. Of these patients, 65.5% (55) had the device implanted within 30 days of transplantation, and 34.5% (29) had late implantation. The mean survival of patients who had an early pacemaker implant was 6.4 years compared to 7.7 years for those with a late pacemaker implant (P<0.05). Sinus node dysfunction and heart block were the most common indications for pacemaker implantation. Starting in 1997, a bicaval technique was used for implantation. The incidence of pacemaker implantation by technique was 2.0% for bicaval and 9.1% for biatrial (P=0.001). Significantly more rejection episodes occurred in the pacemaker group (2.67 ± 2.18) compared with the no-pacemaker group (2.01 ± 2.05) (P<0.05). Conclusion: Our results show a decreased pacemaker need after bicaval anastomosis and that more patients who needed a pacemaker after transplantation had a pretransplant diagnosis of ischemic cardiomyopathy. In our cohort, the need for a permanent pacemaker was also associated with older donor grafts and an increase in the number of treated rejection episodes. PMID:28331443
Chan, Thomas Y K
2009-04-01
Aconitine and related alkaloids found in the Aconitum species are highly toxic cardiotoxins and neurotoxins. The wild plant (especially the roots and root tubers) is extremely toxic. Severe aconite poisoning can occur after accidental ingestion of the wild plant or consumption of an herbal decoction made from aconite roots. In traditional Chinese medicine, aconite roots are used only after processing to reduce the toxic alkaloid content. Soaking and boiling during processing or decoction preparation will hydrolyze aconite alkaloids into less toxic and non-toxic derivatives. However, the use of a larger than recommended dose and inadequate processing increases the risk of poisoning. A Medline search (1963-February 2009) was conducted. Key articles with information on the use of aconite roots in traditional medicine, active (toxic) ingredients, mechanisms of toxicity, toxicokinetics of Aconitum alkaloids, and clinical features and management of aconite poisoning were reviewed. The cardiotoxicity and neurotoxicity of aconitine and related alkaloids are due to their actions on the voltage-sensitive sodium channels of the cell membranes of excitable tissues, including the myocardium, nerves, and muscles. Aconitine and mesaconitine bind with high affinity to the open state of the voltage-sensitive sodium channels at site 2, thereby causing a persistent activation of the sodium channels, which become refractory to excitation. The electrophysiological mechanism of arrhythmia induction is triggered activity due to delayed after-depolarization and early after-depolarization. The arrhythmogenic properties of aconitine are in part due to its cholinolytic (anticholinergic) effects mediated by the vagus nerve. Aconitine has a positive inotropic effect by prolonging sodium influx during the action potential. It has hypotensive and bradycardic actions due to activation of the ventromedial nucleus of the hypothalamus. Through its action on voltage-sensitive sodium channels in the axons, aconitine blocks neuromuscular transmission by decreasing the evoked quantal release of acetylcholine. Aconitine, mesaconitine, and hypaconitine can induce strong contractions of the ileum through acetylcholine release from the postganglionic cholinergic nerves. Patients present predominantly with a combination of neurological, cardiovascular, and gastrointestinal features. The neurological features can be sensory (paresthesia and numbness of face, perioral area, and the four limbs), motor (muscle weakness in the four limbs), or both. The cardiovascular features include hypotension, chest pain, palpitations, bradycardia, sinus tachycardia, ventricular ectopics, ventricular tachycardia, and ventricular fibrillation. The gastrointestinal features include nausea, vomiting, abdominal pain, and diarrhea. The main causes of death are refractory ventricular arrhythmias and asystole and the overall in-hospital mortality is 5.5%. Management of aconite poisoning is supportive, including immediate attention to the vital functions and close monitoring of blood pressure and cardiac rhythm. Inotropic therapy is required if hypotension persists and atropine should be used to treat bradycardia. Aconite-induced ventricular arrhythmias are often refractory to direct current cardioversion and antiarrhythmic drugs. Available clinical evidence suggests that amiodarone and flecainide are reasonable first-line treatment. In refractory cases of ventricular arrhythmias and cardiogenic shock, it is most important to maintain systemic blood flow, blood pressure, and tissue oxygenation by the early use of cardiopulmonary bypass. The role of charcoal hemoperfusion to remove circulating aconitine alkaloids is not established. Aconite roots contain aconitine, mesaconitine, hypaconitine, and other Aconitum alkaloids, which are known cardiotoxins and neurotoxins. Patients present predominantly with neurological, cardiovascular, and gastrointestinal features. Management is supportive; the early use of cardiopulmonary bypass is recommended if ventricular arrhythmias and cardiogenic shock are refractory to first-line treatment.
Arrhythmias in Adults with Congenital Heart Disease: What Are Risk Factors for Specific Arrhythmias?
Loomba, Rohit S; Buelow, Matthew W; Aggarwal, Saurabh; Arora, Rohit R; Kovach, Joshua; Ginde, Salil
2017-04-01
An increasing number of patients with congenital heart disease are now surviving into adulthood. This has also led to the emergence of complications from the underlying congenital heart disease, related surgical interventions, and associated combordities. While the prevalence of particular arrhythmias with specific congenital heart disease has been previously described, a detailed analysis of all lesions and a large number of comorbidities has not been previously published. Admissions with congenital heart disease were identified in the National Inpatient Sample. Associated comorbidities were also identified for these patients. Univariate analysis was done to compare those risk factors associated with specific arrhythmias in the setting of congenital heart disease. Next, regression analysis was done to identify what patient characteristics and comorbidities were associated with increased risk of specific arrhythmias. A total of 52,725,227 admissions were included in the analysis. Of these, 109,168 (0.21%) had congenital heart disease. Of those with congenital heart disease, 27,088 (25%) had an arrhythmia at some point. The most common arrhythmia in those with congenital heart disease was atrial fibrillation, which was noted in 86% of those with arrhythmia followed by atrial flutter which was noted in 20% of those with congenital heart disease. The largest burden of arrhythmia was found to be in those with tricuspid atresia with a 51% prevalence of arrhythmia in this group followed by Ebstein anomaly which had an arrhythmia prevalence of 39%. Increasing age, male gender, double outlet right ventricle, atrioventricular septal defect, heart failure, obstructive sleep apnea, transposition of the great arteries, congenitally corrected transposition, and tetralogy of Fallot were frequently noted to be independent risk factors of specific arrhythmias. Approximately, 25% of adult admissions with congenital heart disease are associated with arrhythmia. The burden of arrhythmia varies by the specific lesion and other risk factors as well. Understanding of these can help in risk stratification and can help devise strategies to lower this risk. © 2016 Wiley Periodicals, Inc.
Gel-Sinuplasty for Chronic Rhinosinusitis With and Without Nasal Polyposis
2018-03-13
Chronic Sinusitis, Ethmoidal; Chronic Sinusitis - Ethmoidal Anterior; Chronic Sinusitis; Chronic Sinusitis - Ethmoidal, Posterior; Chronic Sinusitis, Sphenoidal; Chronic Sinusitis - Frontoethmoidal; Nasal Polyps; Nasal Polyp - Posterior
Haziness in X-Ray Paranasal Sinus Water's View in Sinusitis: A Fact or Fiction.
Gujrathi, Aatish; Wakode, P T
2013-08-01
It is a clinical dilemma whether patients having no symptoms of sinusitis but sinus haziness in X-ray should be considered as sinusitis or not and patients clinically having sinusitis and do not have radiological evidence should be considered as case of sinusitis or not. This study is an attempt to discuss this issue in details. To study diagnostic efficacy of conventional X-ray para nasal sinus water's view in sinusitis. To study the proportion of asymptomatic individuals showing haziness in conventional X-ray para nasal sinus water's view. Sensitivity and specificity of sinus X-ray in combination (conventional + digital) is 95 and 44%, respectively. Proportion of asymptomatic individuals showing haziness in conventional X-ray and digital X-ray paranasal sinus water's view are 52.4 and 75%, respectively. X-ray paranasal sinus water's view undoubtedly yields valuable information regarding sinus pathology. However it should not be accepted as a diagnosis in itself, but considered in the light of patient's history and clinical findings.
Management of unstable arrhythmias in cardiogenic shock.
Saidi, Abdulfattah; Akoum, Nazem; Bader, Feras
2011-08-01
Atrial and ventricular arrhythmias commonly arise in the setting of cardiogenic shock and often result in hemodynamic deterioration. Causative factors include myocardial ischemia, volume overload, and metabolic disturbances. Correcting these factors plays an important role in managing arrhythmias in this setting. Ventricular arrhythmias are more ominous compared to atrial arrhythmias but both require prompt intervention with electrical shock and anti-arrhythmic drug suppression. Coronary reperfusion is key to improving survival, including reducing the risk of sudden cardiac arrest, in acute myocardial infarction. Case series have also demonstrated the value of intra-aortic balloon pump counter-pulsation in suppressing ventricular arrhythmias in cardiogenic shock. The mechanism of arrhythmia suppression may be due to improved coronary perfusion and afterload reduction. Percutaneous ventricular assist device placement may be effective in this setting; however, data addressing this specific endpoint are lacking. Anti-arrhythmic drug options for ventricular and atrial arrhythmia suppression, in the setting of cardiogenic shock, are relatively limited. Common class I agents are excluded due to the inherent abnormal cardiac structure and function in the setting of cardiogenic shock. Class III drug options include dofetilide and amiodarone. The other Class III agents, sotalol and dronedarone, are excluded due to associated mortality observed in the SWORD and ANDROMEDA trials, respectively. Dofetilide is renally excreted and causes QT interval prolongation. Care should be taken to avoid excessive drug accumulation due to poor kidney perfusion and function. Dofetilide is approved for use for atrial arrhythmias and has not been studied for ventricular arrhythmia suppression. The DIAMOND-CHF trial established its safety in the setting of heart failure. Amiodarone is very effective in suppressing both atrial and ventricular arrhythmias. It is often the drug of choice in heart failure. Its off-label use for atrial arrhythmias is very common. Care should be taken with intravenous amiodarone to avoid hypotension.
Cardiac Iodine-123-Meta-Iodo-Benzylguanidine Uptake in Carotid Sinus Hypersensitivity.
Tan, Maw Pin; Murray, Alan; Hawkins, Terry; Chadwick, Thomas J; Kerr, Simon R J; Parry, Steve W
2015-01-01
Carotid sinus syndrome is the association of carotid sinus hypersensitivity with syncope, unexplained falls and drop attacks in generally older people. We evaluated cardiac sympathetic innervation in this disorder in individuals with carotid sinus syndrome, asymptomatic carotid sinus hypersensitivity and controls without carotid sinus hypersensitivity. Consecutive patients diagnosed with carotid sinus syndrome at a specialist falls and syncope unit were recruited. Asymptomatic carotid sinus hypersensitivity and non-carotid sinus hypersensitivity control participants recruited from a community-dwelling cohort. Cardiac sympathetic innervation was determined using Iodine-123-metaiodobenzylguanidine (123-I-MIBG) scanning. Heart to mediastinal uptake ratio (H:M) were determined for early and late uptake on planar scintigraphy at 20 minutes and 3 hours following intravenous injection of 123-I-MIBG. Forty-two subjects: carotid sinus syndrome (n = 21), asymptomatic carotid sinus hypersensitivity (n = 12) and no carotid sinus hypersensitivity (n = 9) were included. Compared to the non- carotid sinus hypersensitivity control group, the carotid sinus syndrome group had significantly higher early H:M (estimated mean difference, B = 0.40; 95% confidence interval, CI = 0.13 to 0.67, p = 0.005) and late H:M (B = 0.32; 95%CI = 0.03 to 0.62, p = 0.032). There was, however, no significant difference in early H:M (p = 0.326) or late H:M (p = 0.351) between the asymptomatic carotid sinus hypersensitivity group and non- carotid sinus hypersensitivity controls. Cardiac sympathetic neuronal activity is increased relative to age-matched controls in individuals with carotid sinus syndrome but not those with asymptomatic carotid sinus hypersensitivity. Blood pressure and heart rate measurements alone may therefore represent an over simplification in the assessment for carotid sinus syndrome and the relative increase in cardiac sympathetic innervation provides additional clues to understanding the mechanisms behind the symptomatic presentation of carotid sinus hypersensitivity.
Sinuses / Sinusitis / Rhinosinusitis
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Xu, Xianrong; Ma, Xiaoli; Zhang, Yang; Xiong, Wei
2012-01-01
To comparatively analyze the disease data of nasal sinus between helicopter and (strike) fighter pilots under flying qualification, and then to provide references for aeromedical support as a significant part of new logistics service union in army, The CT data of nasal sinus in 138 pilots who accepted physical examination for change to new-type aircraft, were collected included 46 cases of helicopter pilots and 92 cases of (strike)fighter pilots). The incidence of chronic sinusitis and cyst of nasal sinus were computed respectively in helicopter pilots and (strike)fighter pilots. (1) Fourteen cases suffered from chronic sinusitis (6 cases of maxillary sinusitis, 4 cases of ethmoiditis and 4 cases of maxillary sinusitis and ethmoiditis) in helicopter pilots whose incidence rate of chronic sinusitis was 30.4% (14/46). Of which, 3 cases of antracele were treated. Twelve cases suffered from chronic sinusitis (8 cases of maxillary sinusitis, 1 case of ethmoiditis, 3 cases of maxillary sinusitis and ethmoiditis) in (strike)fighter pilots whose incidence of chronic sinusitis was 13.0% (12/92). Of which, 1 case of antracele was treated. The incidence of chronic sinusitis was higher in helicopter pilots than (strike) fighters pilots (Chi2 = 6.07, P < 0.05). (2) Four cases suffered from unilateral mucosa cysts in maxillary sinus in helicopter pilots whose incidence of cyst of nasal sinus was 8.7% (4/46). Ten cases suffered from mucosa cysts in maxillary sinus (unilateral 8 cases and bilateral 2 cases) in (strike) fighters pilots whose incidence of cyst of nasal sinus was 10.87% (10/92). The difference of the incidence of cyst of nasal sinus was not statistically significant between the helicopter pilots and(strike)fighters pilots. The cysts of nasal sinus did not need treatment in 14 cases of this group data. The incidence of symptomless chronic sinusitis and cyst of nasal sinus are high in pilots. It is related with repeatedly changes of atmosphere pressure during flying. But most chronic sinusitis and cyst of nasal sinus do not need treatment. The incidence of chronic sinusitis is higher in helicopter pilots than(strike)fighter pilots. It may be related with the environment of helicopter which have unclosed cockpit and load other aircrew.
Marcantoni, Lina; Toselli, Tiziano; Urso, Giulia; Pratola, Claudio; Ceconi, Claudio; Bertini, Matteo
2015-11-01
In the last decade, there has been an exponential increase in cardioverter-defibrillator (ICD) implants. Remote monitoring systems, allow daily follow-ups of patients with ICD. To evaluate the impact of remote monitoring on the management of cardiovascular events associated with supraventricular and ventricular arrhythmias during long-term follow-up. A total of 207 patients undergoing ICD implantation/replacement were enrolled: 79 patients received remote monitoring systems and were followed up every 12 months, and 128 patients were followed up conventionally every 6 months. All patients were followed up and monitored for the occurrence of supraventricular and ventricular arrhythmia-related cardiovascular events (ICD shocks and/or hospitalizations). During a median follow-up of 842 days (interquartile range 476-1288 days), 32 (15.5%) patients experienced supraventricular arrhythmia-related events and 51 (24.6%) patients experienced ventricular arrhythmia-related events. Remote monitoring had a significant role in the reduction of supraventricular arrhythmia-related events, but it had no effect on ventricular arrhythmia-related events. In multivariable analysis, remote monitoring remained as an independent protective factor, reducing the risk of supraventricular arrhythmia-related events of 67% [hazard ratio, 0.33; 95% confidence interval (CI), 0.13-0.82; P = 0.017]. Remote monitoring systems improved outcomes in patients with supraventricular arrhythmias by reducing the risk of cardiovascular events, but no benefits were observed in patients with ventricular arrhythmias.
Plain Language Summary: Adult Sinusitis (Sinus Infection).
Caspersen, Leslie A; Walter, Lindsey M; Walsh, Sandra A; Rosenfeld, Richard M; Piccirillo, Jay F
2015-08-01
This plain language summary serves as an overview in explaining sinusitis (pronounced sign-you-side-tis). The purpose of this plain language summary is to provide patients with standard language explaining their condition in an easy-to-read format. This summary applies to those 18 years of age or older with sinusitis. The summary is featured as an FAQ (frequently asked question) format. The summary addresses how to manage and treat sinusitis symptoms. Adult sinusitis is often called a sinus infection. A healthcare provider may refer to a sinus infection as rhinosinusitis (pronounced rhi-no-sign-you-side-tis). This includes the nose as well as the sinuses in the name. A sinus infection is the swelling of the sinuses and nasal cavity.The summary is based on the published 2015 "Clinical Practice Guideline: Adult Sinusitis." The evidence-based guideline includes research to support more effective diagnosis and treatment of adult sinus infections. The guideline was developed as a quality improvement opportunity for managing sinus infections by creating clear recommendations to use in medical practice. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.
2017-07-11
Stage 0 Nasopharyngeal Carcinoma; Stage 0 Paranasal Sinus Cancer; Stage I Nasopharyngeal Carcinoma; Stage I Paranasal Sinus Cancer; Stage II Nasopharyngeal Carcinoma; Stage II Paranasal Sinus Cancer; Stage IIA Nasopharyngeal Carcinoma; Stage IIB Nasopharyngeal Carcinoma; Stage III Nasopharyngeal Carcinoma; Stage III Paranasal Sinus Cancer; Stage IV Nasopharyngeal Carcinoma; Stage IV Paranasal Sinus Cancer; Stage IVA Nasopharyngeal Carcinoma; Stage IVA Paranasal Sinus Cancer; Stage IVB Nasopharyngeal Carcinoma; Stage IVB Paranasal Sinus Cancer; Stage IVC Nasopharyngeal Carcinoma; Stage IVC Paranasal Sinus Cancer
[The treatment principles of frontal sinus tract after the frontal approach craniotomy].
Yu, Huanxin; Li, Haiyan; Liu, Gang
2015-12-01
To investigate the causes, clinical manifestation and treatment principles of frontal sinus tract after the frontal approach craniotomy. The clinic data of 13 patients with frontal skin sinus tract after the frontal approach craniotomy were retrospectively analyzed. All of them were described in the clinical record to have undergone frontal sinus mucosa pushing down or shaving and bone wax filling in the frontal sinus during the surgery, of whom 3 cases had history of frontal abscess incision drainage. All patients were performed endoscopic frontal sinus surgery and forehead skin sinus tract excision and suture. All of the patients successfully recovered after one-stage operation, and the frontal skin sinus tract was healed. The frontal approach craniotomy with postoperative frontal sinus tract was related with the improper use of bone wax tamponade and sealing of frontal sinus. The treatment principles were to remove bone wax, remove inflammatory granulation tissue around the sinus tract, and to open frontal sinus and promote frontal sinus drainage.
Perspective: A Dynamics-Based Classification of Ventricular Arrhythmias
Weiss, James N.; Garfinkel, Alan; Karagueuzian, Hrayr S.; Nguyen, Thao P.; Olcese, Riccardo; Chen, Peng-Sheng; Qu, Zhilin
2015-01-01
Despite key advances in the clinical management of life-threatening ventricular arrhythmias, culminating with the development of implantable cardioverter-defibrillators and catheter ablation techniques, pharmacologic/biologic therapeutics have lagged behind. The fundamental issue is that biological targets are molecular factors. Diseases, however, represent emergent properties at the scale of the organism that result from dynamic interactions between multiple constantly changing molecular factors. For a pharmacologic/biologic therapy to be effective, it must target the dynamic processes that underlie the disease. Here we propose a classification of ventricular arrhythmias that is based on our current understanding of the dynamics occurring at the subcellular, cellular, tissue and organism scales, which cause arrhythmias by simultaneously generating arrhythmia triggers and exacerbating tissue vulnerability. The goal is to create a framework that systematically links these key dynamic factors together with fixed factors (structural and electrophysiological heterogeneity) synergistically promoting electrical dispersion and increased arrhythmia risk to molecular factors that can serve as biological targets. We classify ventricular arrhythmias into three primary dynamic categories related generally to unstable Ca cycling, reduced repolarization, and excess repolarization, respectively. The clinical syndromes, arrhythmia mechanisms, dynamic factors and what is known about their molecular counterparts are discussed. Based on this framework, we propose a computational-experimental strategy for exploring the links between molecular factors, fixed factors and dynamic factors that underlie life-threatening ventricular arrhythmias. The ultimate objective is to facilitate drug development by creating an in silico platform to evaluate and predict comprehensively how molecular interventions affect not only a single targeted arrhythmia, but all primary arrhythmia dynamics categories as well as normal cardiac excitation-contraction coupling. PMID:25769672
The microbiology of ethmoid and maxillary sinuses in patients with chronic sinusitis.
Aral, Murat; Keles, Erol; Kaygusuz, Irfan
2003-01-01
To investigate aerob-anaerob microorganisms growth in maxillary and ethmoid sinuses by evaluating aspiration materials from patients with chronic sinusitis. The study was performed prospectively, and there were 31 patients (23 men, 8 women; mean age, 31.4+/-14.15, between 18-65 years) who had endoscopic sinus surgery because of chronic sinusitis. During the operation, when the maxillary sinus ostium and ethmoid sinus were opened, readily aspirated materials from sinuses were evaluated regarding aerob and anaerob bacteria. Nose and throat swap samples were collected preoperatively to determine the upper respiratory tract flora and also to understand the relationship between the flora and the microorganisms aspirated from sinuses. Total aerob bacteria count, which was isolated from preoperative nasal swab cultures, was 36, and aerob-anaerob bacteria count that included cultures taken from maxillary and ethmoid sinuses during the functional endoscopic sinus surgery was 42. For each 2 samples, the most common isolated aerob bacteria were coagulase (-) staphylococci. Microorganisms were isolated in 87.0% of 27 patients, in which cultures taken from maxillary and ethmoid sinuses during the functional endoscopic sinus surgery were included. It is determined that the isolated aerob bacteria rate was 90.4%, and the isolated anaerob bacteria rate was 14.2%. All of the 6 samples in which anaerob bacteria isolated were all maxillary sinus aspiration materials. Microorganisms that isolated from the nose and the sinuses were similar with the rate of 25.8%, and microorganisms that isolated from the throat cultures and sinuses were similar with the rate of 22.5%. This study reveals the aerob and anaerob microbiology of the maxillary and ethmoid sinuses so the treatment of chronic sinusitis will be easier.
2014-01-01
Background Sinusitis is a common disease in the horse. In human medicine it is described, that obstruction of the sinonasal communication plays a major role in the development of sinusitis. To get spatial sense of the equine specific communication ways between the nasal cavity and the paranasal sinuses, heads of 19 horses, aged 2 to 26 years, were analyzed using three-dimensional (3D) reformatted renderings of CT-datasets. Three-dimensional models were generated following manual and semi-automated segmentation. Before segmentation, the two-dimensional (2D) CT-images were verified against corresponding frozen sections of cadaveric heads. Results Three-dimensional analysis of the paranasal sinuses showed the bilateral existence of seven sinus compartments: rostral maxillary sinus, ventral conchal sinus, caudal maxillary sinus, dorsal conchal sinus, frontal sinus, sphenopalatine sinus and middle conchal sinus. The maxillary septum divides these seven compartments into two sinus systems: a rostral paranasal sinus system composed of the rostral maxillary sinus and the ventral conchal sinus and a caudal paranasal sinus system which comprises all other sinuses. The generated 3D models revealed a typically configuration of the sinonasal communication ways. The sinonasal communication started within the middle nasal meatus at the nasomaxillary aperture (Apertura nasomaxillaris), which opens in a common sinonasal channel (Canalis sinunasalis communis). This common sinonasal channel ramifies into a rostral sinonasal channel (Canalis sinunasalis rostralis) and a caudo-lateral sinonasal channel (Canalis sinunasalis caudalis). The rostral sinonasal channel ventilated the rostral paranasal sinus system, the caudo-lateral sinonasal channel opened into the caudal paranasal sinus system. The rostral sinonasal channel was connected to the rostral paranasal sinuses in various ways. Whereas, the caudal channel showed less anatomical variations and was in all cases connected to the caudal maxillary sinus. Volumetric measurements of the sinonasal channels showed no statistically significant differences (P <0.05) between the right and left side of the head. Conclusions Under physiologic conditions both paranasal sinus systems are connected to the nasal cavity by equine specific sinonasal channels. To resolve sinus disease it is aimed to maintain or even reconstruct the normal anatomy of the sinonasal communication by surgical intervention. Therefore, the presented 3D analyses may provide a useful basis. PMID:24646003
Evidence Based Review: Risk of Cardiac Rhythm Problems During Spaceflight
NASA Technical Reports Server (NTRS)
Platts, Steven H.; Stenger, Michael B.; Phillips, Tiffany R.; Brown, Angela K.; Arzeno, Natalia M.; Levine, Benjamin; Summers, Richard
2009-01-01
Very little research has systematically evaluated the prevalence (or potential risk) of cardiac arrhythmias during space flight. There are several observational reports of non life-threatening but potentially concerning arrhythmias. At least two potential risk factors for arrhythmias have been reported either during or immediately after space flight: cardiac atrophy and a prolonged QTc interval. The potential severity of the mission impact of a serious arrhythmia requires that a systematic evaluation be conducted of the risk of arrhythmia due to space flight.
Costet, Alexandre; Wan, Elaine; Bunting, Ethan; Grondin, Julien; Garan, Hasan; Konofagou, Elisa
2016-01-01
Characterization and mapping of arrhythmias is currently performed through invasive insertion and manipulation of cardiac catheters. Electromechanical wave imaging (EWI) is a non-invasive ultrasound-based imaging technique, which tracks the electromechanical activation that immediately follows electrical activation. Electrical and electromechanical activations were previously found to be linearly correlated in the left ventricle, but the relationship has not yet been investigated in the three other chambers of the heart. The objective of this study was to investigate the relationship between electrical and electromechanical activations and validate EWI in all four chambers of the heart with conventional 3D electroanatomical mapping. Six (n = 6) normal adult canines were used in this study. The electrical activation sequence was mapped in all four chambers of the heart, both endocardially and epicardially using the St Jude's EnSite 3D mapping system (St. Jude Medical, Secaucus, NJ). EWI acquisitions were performed in all four chambers during normal sinus rhythm, and during pacing in the left ventricle. Isochrones of the electromechanical activation were generated from standard echocardiographic imaging views. Electrical and electromechanical activation maps were co-registered and compared, and electrical and electromechanical activation times were plotted against each other and linear regression was performed for each pair of activation maps. Electromechanical and electrical activations were found to be directly correlated with slopes of the correlation ranging from 0.77 to 1.83, electromechanical delays between 9 and 58 ms and R2 values from 0.71 to 0.92. The linear correlation between electrical and electromechanical activations and the agreement between the activation maps indicate that the electromechanical activation follows the pattern of propagation of the electrical activation. This suggests that EWI may be used as a novel non-invasive method to accurately characterize and localize sources of arrhythmias. PMID:27782003
Costet, Alexandre; Wan, Elaine; Bunting, Ethan; Grondin, Julien; Garan, Hasan; Konofagou, Elisa
2016-11-21
Characterization and mapping of arrhythmias is currently performed through invasive insertion and manipulation of cardiac catheters. Electromechanical wave imaging (EWI) is a non-invasive ultrasound-based imaging technique, which tracks the electromechanical activation that immediately follows electrical activation. Electrical and electromechanical activations were previously found to be linearly correlated in the left ventricle, but the relationship has not yet been investigated in the three other chambers of the heart. The objective of this study was to investigate the relationship between electrical and electromechanical activations and validate EWI in all four chambers of the heart with conventional 3D electroanatomical mapping. Six (n = 6) normal adult canines were used in this study. The electrical activation sequence was mapped in all four chambers of the heart, both endocardially and epicardially using the St Jude's EnSite 3D mapping system (St. Jude Medical, Secaucus, NJ). EWI acquisitions were performed in all four chambers during normal sinus rhythm, and during pacing in the left ventricle. Isochrones of the electromechanical activation were generated from standard echocardiographic imaging views. Electrical and electromechanical activation maps were co-registered and compared, and electrical and electromechanical activation times were plotted against each other and linear regression was performed for each pair of activation maps. Electromechanical and electrical activations were found to be directly correlated with slopes of the correlation ranging from 0.77 to 1.83, electromechanical delays between 9 and 58 ms and R 2 values from 0.71 to 0.92. The linear correlation between electrical and electromechanical activations and the agreement between the activation maps indicate that the electromechanical activation follows the pattern of propagation of the electrical activation. This suggests that EWI may be used as a novel non-invasive method to accurately characterize and localize sources of arrhythmias.
DeMazumder, Deeptankar; Limpitikul, Worawan B; Dorante, Miguel; Dey, Swati; Mukhopadhyay, Bhasha; Zhang, Yiyi; Moorman, J Randall; Cheng, Alan; Berger, Ronald D; Guallar, Eliseo; Jones, Steven R; Tomaselli, Gordon F
2016-12-01
The need for a readily available, inexpensive, non-invasive method for improved risk stratification of heart failure (HF) patients is paramount. Prior studies have proposed that distinct fluctuation patterns underlying the variability of physiological signals have unique prognostic value. We tested this hypothesis in an extensively phenotyped cohort of HF patients using EntropyX QT , a novel non-linear measure of cardiac repolarization dynamics. In a prospective, multicentre, observational study of 852 patients in sinus rhythm undergoing clinically indicated primary prevention implantable cardioverter-defibrillator (ICD) implantation (2003-10), exposures included demographics, history, physical examination, medications, laboratory results, serum biomarkers, ejection fraction, conventional electrocardiographic (ECG) analyses of heart rate and QT variability, and EntropyX QT . The primary outcome was first 'appropriate' ICD shock for ventricular arrhythmias. The secondary outcome was composite events (appropriate ICD shock and all-cause mortality). After exclusions, the cohort (n = 816) had a mean age of 60 ± 13 years, 28% women, 36% African Americans, 56% ischaemic cardiomyopathy, and 29 ± 16% Seattle HF risk score (SHFS) 5-year predicted mortality. Over 45 ± 24 months, there were 134 appropriate shocks and 166 deaths. After adjusting for 30 exposures, the hazard ratios (comparing the 5th to 1st quintile of EntropyX QT ) for primary and secondary outcomes were 3.29 (95% CI 1.74-6.21) and 2.28 (1.53-3.41), respectively. Addition of EntropyX QT to a model comprised of the exposures or SHFS significantly increased net reclassification and the ROC curve area. EntropyX QT measured during ICD implantation strongly and independently predicts appropriate shock and all-cause mortality over follow-up. EntropyX QT complements conventional risk predictors and has the potential for broad clinical application. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.
Rozen, Guy; Vaid, Jeena; Hosseini, Seyed Mohammadreza; Kaadan, M Ihsan; Rafael, Allon; Roka, Attila; Poh, Yukkee C; Poh, Ming-Zher; Heist, Edwin Kevin; Ruskin, Jeremy Neil
2018-05-15
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in adults, associated with significant morbidity, increased mortality, and rising health-care costs. Simple and available tools for the accurate detection of arrhythmia recurrence in patients after electrical cardioversion (CV) or ablation procedures for AF can help to guide therapeutic decisions. We conducted a prospective, single-center study to evaluate the accuracy of Cardiio Rhythm Mobile Application (CRMA) for AF detection. Patients >18 years of age who were scheduled for elective CV for AF were enrolled in the study. CRMA finger pulse recordings, utilizing an iPhone camera, were obtained before (pre-CV) and after (post-CV) the CV. The findings were validated against surface electrocardiograms. Ninety-eight patients (75.5% men), mean age of 67.7 ± 10.5 years, were enrolled. No electrocardiogram for validation was available in 1 case. Pre-CV CRMA readings were analyzed in 97 of the 98 patients. Post-CV CRMA readings were analyzed for 92 of 93 patients who underwent CV. One patient left before the recording was obtained. The Cardiio Rhythm Mobile Application correctly identified 94 of 101 AF recordings (93.1%) as AF and 80 of 88 non-AF recordings (90.1%) as non-AF. The sensitivity was 93.1% (95% confidence interval [CI] = 86.9% to 97.2%) and the specificity was 90.9% (95% CI = 82.9% to 96.0%). The positive predictive value was 92.2% (95% CI = 85.8% to 95.8%) and the negative predictive value was 92.0% (95% CI = 94.8% to 95.9%). In conclusion, the CRMA demonstrates promising potential in accurate detection and discrimination of AF from normal sinus rhythm in patients with a history of AF. Copyright © 2018 Elsevier Inc. All rights reserved.
Yu, Lilei; Huang, Bing; Po, Sunny S; Tan, Tuantuan; Wang, Menglong; Zhou, Liping; Meng, Guannan; Yuan, Shenxu; Zhou, Xiaoya; Li, Xuefei; Wang, Zhuo; Wang, Songyun; Jiang, Hong
2017-08-14
The aim of this study was to investigate whether low-level tragus stimulation (LL-TS) treatment could reduce myocardial ischemia-reperfusion injury in patients with ST-segment elevation myocardial infarction (STEMI). The authors' previous studies suggested that LL-TS could reduce the size of myocardial injury induced by ischemia. Patients who presented with STEMI within 12 h of symptom onset, treated with primary percutaneous coronary intervention, were randomized to the LL-TS group (n = 47) or the control group (with sham stimulation [n = 48]). LL-TS, 50% lower than the electric current that slowed the sinus rate, was delivered to the right tragus once the patients arrived in the catheterization room and lasted for 2 h after balloon dilatation (reperfusion). All patients were followed for 7 days. The occurrence of reperfusion-related arrhythmia, blood levels of creatine kinase-MB, myoglobin, N-terminal pro-B-type natriuretic peptide and inflammatory markers, and echocardiographic characteristics were evaluated. The incidence of reperfusion-related ventricular arrhythmia during the first 24 h was significantly attenuated by LL-TS. In addition, the area under the curve for creatine kinase-MB and myoglobin over 72 h was smaller in the LL-TS group than the control group. Furthermore, blood levels of inflammatory markers were decreased by LL-TS. Cardiac function, as demonstrated by the level of N-terminal pro-B-type natriuretic peptide, the left ventricular ejection fraction, and the wall motion index, was markedly improved by LL-TS. LL-TS reduces myocardial ischemia-reperfusion injury in patients with STEMI. This proof-of-concept study raises the possibility that this noninvasive strategy may be used to treat patients with STEMI undergoing primary percutaneous coronary intervention. Copyright © 2017. Published by Elsevier Inc.
Alday, Erick A. Perez; Colman, Michael A.; Langley, Philip; Butters, Timothy D.; Higham, Jonathan; Workman, Antony J.; Hancox, Jules C.; Zhang, Henggui
2015-01-01
Rapid atrial arrhythmias such as atrial fibrillation (AF) predispose to ventricular arrhythmias, sudden cardiac death and stroke. Identifying the origin of atrial ectopic activity from the electrocardiogram (ECG) can help to diagnose the early onset of AF in a cost-effective manner. The complex and rapid atrial electrical activity during AF makes it difficult to obtain detailed information on atrial activation using the standard 12-lead ECG alone. Compared to conventional 12-lead ECG, more detailed ECG lead configurations may provide further information about spatio-temporal dynamics of the body surface potential (BSP) during atrial excitation. We apply a recently developed 3D human atrial model to simulate electrical activity during normal sinus rhythm and ectopic pacing. The atrial model is placed into a newly developed torso model which considers the presence of the lungs, liver and spinal cord. A boundary element method is used to compute the BSP resulting from atrial excitation. Elements of the torso mesh corresponding to the locations of the placement of the electrodes in the standard 12-lead and a more detailed 64-lead ECG configuration were selected. The ectopic focal activity was simulated at various origins across all the different regions of the atria. Simulated BSP maps during normal atrial excitation (i.e. sinoatrial node excitation) were compared to those observed experimentally (obtained from the 64-lead ECG system), showing a strong agreement between the evolution in time of the simulated and experimental data in the P-wave morphology of the ECG and dipole evolution. An algorithm to obtain the location of the stimulus from a 64-lead ECG system was developed. The algorithm presented had a success rate of 93%, meaning that it correctly identified the origin of atrial focus in 75/80 simulations, and involved a general approach relevant to any multi-lead ECG system. This represents a significant improvement over previously developed algorithms. PMID:25611350
Zhu, Jian Hua; Lee, Heow Pueh; Lim, Kian Meng; Gordon, Bruce R; Wang, De Yun
2012-08-15
We evaluated, by CFD simulation, effects of accessory ostium (AO) on maxillary sinus ventilation. A three-dimensional nasal model was constructed from an adult CT scan with two left maxillary AOs (sinus I) and one right AO (sinus II), then compared to an identical control model with all AOs sealed (sinuses III and IV). Transient simulations of quiet inspiration and expiration at 15 L/min, and nasal blow at 48 L/min, were calculated for both models using low-Reynolds-number turbulent analysis. At low flows, ventilation rates in sinuses with AOs (I ≈ 0.46 L/min, II ≈ 0.54 L/min), were both more than a magnitude higher than sinuses without AOs (II I ≈ 0.019 L/min, IV ≈ 0.020 L/min). Absence of AO almost completely prevented sinus ventilation. Increased ventilation of sinuses with AOs is complex. Under high flow conditions mimicking nose blowing, in sinuses II, III, and IV, the sinus flow rate increased. In contrast, the airflow direction through sinus I reversed between inspiration and expiration, while it remained almost constant throughout the respiration cycle in sinus II. CFD simulation demonstrated that AOs markedly increase maxillary sinus airflow rates and alter sinus air circulation patterns. Whether these airflow changes impact maxillary sinus physiology or pathophysiology is unknown. Copyright © 2012 Elsevier B.V. All rights reserved.
Lansley, J A; Tucker, W; Eriksen, M R; Riordan-Eva, P; Connor, S E J
2017-09-01
Pulsatile tinnitus is experienced by most patients with idiopathic intracranial hypertension. The pathophysiology remains uncertain; however, transverse sinus stenosis and sigmoid sinus diverticulum/dehiscence have been proposed as potential etiologies. We aimed to determine whether the prevalence of transverse sinus stenosis and sigmoid sinus diverticulum/dehiscence was increased in patients with idiopathic intracranial hypertension and pulsatile tinnitus relative to those without pulsatile tinnitus and a control group. CT vascular studies of patients with idiopathic intracranial hypertension with pulsatile tinnitus ( n = 42), without pulsatile tinnitus ( n = 37), and controls ( n = 75) were independently reviewed for the presence of severe transverse sinus stenosis and sigmoid sinus diverticulum/dehiscence according to published criteria. The prevalence of transverse sinus stenosis and sigmoid sinus diverticulum/dehiscence in patients with idiopathic intracranial hypertension with pulsatile tinnitus was compared with that in the nonpulsatile tinnitus idiopathic intracranial hypertension group and the control group. Further comparisons included differing degrees of transverse sinus stenosis (50% and 75%), laterality of transverse sinus stenosis/sigmoid sinus diverticulum/dehiscence, and ipsilateral transverse sinus stenosis combined with sigmoid sinus diverticulum/dehiscence. Severe bilateral transverse sinus stenoses were more frequent in patients with idiopathic intracranial hypertension than in controls ( P < .001), but there was no significant association between transverse sinus stenosis and pulsatile tinnitus within the idiopathic intracranial hypertension group. Sigmoid sinus dehiscence (right- or left-sided) was also more common in patients with idiopathic intracranial hypertension compared with controls ( P = .01), but there was no significant association with pulsatile tinnitus within the idiopathic intracranial hypertension group. While our data corroborate previous studies demonstrating increased prevalence of sigmoid sinus diverticulum/dehiscence and transverse sinus stenosis in idiopathic intracranial hypertension, we did not establish an increased prevalence in patients with idiopathic intracranial hypertension with pulsatile tinnitus compared with those without. It is therefore unlikely that these entities represent a direct structural correlate of pulsatile tinnitus in patients with idiopathic intracranial hypertension. © 2017 by American Journal of Neuroradiology.
Cardiac Iodine-123-Meta-Iodo-Benzylguanidine Uptake in Carotid Sinus Hypersensitivity
Tan, Maw Pin; Murray, Alan; Hawkins, Terry; Chadwick, Thomas J.; Kerr, Simon R. J.; Parry, Steve W.
2015-01-01
Background Carotid sinus syndrome is the association of carotid sinus hypersensitivity with syncope, unexplained falls and drop attacks in generally older people. We evaluated cardiac sympathetic innervation in this disorder in individuals with carotid sinus syndrome, asymptomatic carotid sinus hypersensitivity and controls without carotid sinus hypersensitivity. Methods Consecutive patients diagnosed with carotid sinus syndrome at a specialist falls and syncope unit were recruited. Asymptomatic carotid sinus hypersensitivity and non-carotid sinus hypersensitivity control participants recruited from a community-dwelling cohort. Cardiac sympathetic innervation was determined using Iodine-123-metaiodobenzylguanidine (123-I-MIBG) scanning. Heart to mediastinal uptake ratio (H:M) were determined for early and late uptake on planar scintigraphy at 20 minutes and 3 hours following intravenous injection of 123-I-MIBG. Results Forty-two subjects: carotid sinus syndrome (n = 21), asymptomatic carotid sinus hypersensitivity (n = 12) and no carotid sinus hypersensitivity (n = 9) were included. Compared to the non- carotid sinus hypersensitivity control group, the carotid sinus syndrome group had significantly higher early H:M (estimated mean difference, B = 0.40; 95% confidence interval, CI = 0.13 to 0.67, p = 0.005) and late H:M (B = 0.32; 95%CI = 0.03 to 0.62, p = 0.032). There was, however, no significant difference in early H:M (p = 0.326) or late H:M (p = 0.351) between the asymptomatic carotid sinus hypersensitivity group and non- carotid sinus hypersensitivity controls. Conclusions Cardiac sympathetic neuronal activity is increased relative to age-matched controls in individuals with carotid sinus syndrome but not those with asymptomatic carotid sinus hypersensitivity. Blood pressure and heart rate measurements alone may therefore represent an over simplification in the assessment for carotid sinus syndrome and the relative increase in cardiac sympathetic innervation provides additional clues to understanding the mechanisms behind the symptomatic presentation of carotid sinus hypersensitivity. PMID:26057525
21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to produce...
21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to produce...
21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to produce...
[Causes and management of frontal sinusitis after transfrontal craniotomy].
Liu, T C; Yu, X F; Gu, Z W; Bai, W L; Wang, Z H; Cao, Z W
2018-02-01
Objective: The aim of this study is to investigate the causes and the strategy of frontal sinusitis after transfrontal craniotomy by endoscopic frontal sinus surgery and traditional surgery with facial incision. Method: A total of thirty-four patients with frontal sinusitis after transfrontal craniotomy were admitted, with the symptom of purulence stuff, headache and upper eyelid discharging. The onset time was 2.6 years on average. The frontal sinus CT and MRI images showed frontal sinusitis. Twenty-seven patients were treated with endoscopic frontal sinus surgery, and seven patient was treated with combined endoscopic and traditional frontal sinus surgery. In the revision surgery, the bone wax and inflammatory granulation tissue were cleaned out in both operational methods. The cure standard was that the postoperative frontal sinus inflammation disappeared and the drainage of the volume recess was unobstructed. Result: Thirty-four patients had a history of transfrontal craniotomy, and there was a record of bone wax packing in every operation. Among twenty-seven patients with endoscopic frontal sinus surgery, Twenty-five cases cured and two cases were operated twice. Seven patients were cured with combined endoscopic and traditional frontal sinus surgery. Conclusion: The frontal sinusitis after transfrontal craniotomy may be related to the inadequate sinus management, especially bone wax to be addressed to the frontal sinus ramming leading to frontal sinus mucosa secretion obstruction and poor drainage. Endoscopic frontal sinus surgery is a way of minimally invasive surgery. The satisfying curative effect can be obtained by endoscopic removal of bone wax, inflammatory granulation tissue, and the enlargement of frontal sinus aperture after exposure to the frontal sinus, and some cases was treated with both operation method.
Selim, Bernardo J; Koo, Brian B; Qin, Li; Jeon, Sangchoon; Won, Christine; Redeker, Nancy S; Lampert, Rachel J; Concato, John P; Bravata, Dawn M; Ferguson, Jared; Strohl, Kingman; Bennett, Adam; Zinchuk, Andrey; Yaggi, Henry K
2016-06-15
To determine whether sleep-disordered breathing (SDB) is associated with cardiac arrhythmia in a clinic-based population with multiple cardiovascular comorbidities and severe SDB. This was a cross-sectional analysis of 697 veterans who underwent polysomnography for suspected SDB. SDB was categorized according to the apnea-hypopnea index (AHI): none (AHI < 5), mild (5 ≥ AHI < 15), and moderate-severe (AHI ≥ 15). Nocturnal cardiac arrhythmias consisted of: (1) complex ventricular ectopy, (CVE: non-sustained ventricular tachycardia, bigeminy, trigeminy, or quadrigeminy), (2) combined supraventricular tachycardia, (CST: atrial fibrillation or supraventricular tachycardia), (3) intraventricular conduction delay (ICD), (4) tachyarrhythmias (ventricular and supraventricular), and (5) any cardiac arrhythmia. Unadjusted, adjusted logistic regression, and Cochran-Armitage testing examined the association between SDB and cardiac arrhythmias. Linear regression models explored the association between hypoxia, arousals, and cardiac arrhythmias. Compared to those without SDB, patients with moderate-severe SDB had almost three-fold unadjusted odds of any cardiac arrhythmia (2.94; CI 95%, 2.01-4.30; p < 0.0001), two-fold odds of tachyarrhythmias (2.16; CI 95%,1.47-3.18; p = 0.0011), two-fold odds of CVE (2.01; 1.36-2.96; p = 0.003), and two-fold odds of ICD (2.50; 1.58-3.95; p = 0.001). A linear trend was identified between SDB severity and all cardiac arrhythmia subtypes (p value linear trend < 0.0001). After adjusting for age, BMI, gender, and cardiovascular diseases, moderate-severe SDB patients had twice the odds of having nocturnal cardiac arrhythmias (2.24; 1.48-3.39; p = 0.004). Frequency of obstructive respiratory events and hypoxia were strong predictors of arrhythmia risk. SDB is independently associated with nocturnal cardiac arrhythmias. Increasing severity of SDB was associated with an increasing risk for any cardiac arrhythmia. © 2016 American Academy of Sleep Medicine.
Labombarda, Fabien; Hamilton, Robert; Shohoudi, Azadeh; Aboulhosn, Jamil; Broberg, Craig S; Chaix, Marie A; Cohen, Scott; Cook, Stephen; Dore, Annie; Fernandes, Susan M; Fournier, Anne; Kay, Joseph; Macle, Laurent; Mondésert, Blandine; Mongeon, François-Pierre; Opotowsky, Alexander R; Proietti, Anna; Rivard, Lena; Ting, Jennifer; Thibault, Bernard; Zaidi, Ali; Khairy, Paul
2017-08-15
Atrial arrhythmias are the most common complication encountered in the growing and aging population with congenital heart disease. This study sought to assess the types and patterns of atrial arrhythmias, associated factors, and age-related trends. A multicenter cohort study enrolled 482 patients with congenital heart disease and atrial arrhythmias, age 32.0 ± 18.0 years, 45.2% female, from 12 North American centers. Qualifying arrhythmias were classified by a blinded adjudicating committee. The most common presenting arrhythmia was intra-atrial re-entrant tachycardia (IART) (61.6%), followed by atrial fibrillation (28.8%), and focal atrial tachycardia (9.5%). The proportion of arrhythmias due to IART increased with congenital heart disease complexity from 47.2% to 62.1% to 67.0% in patients with simple, moderate, and complex defects, respectively (p = 0.0013). Atrial fibrillation increased with age to surpass IART as the most common arrhythmia in those ≥50 years of age (51.2% vs. 44.2%; p < 0.0001). Older age (odds ratio [OR]: 1.024 per year; 95% confidence interval [CI]: 1.010 to 1.039; p = 0.001) and hypertension (OR: 2.00; 95% CI: 1.08 to 3.71; p = 0.029) were independently associated with atrial fibrillation. During a mean follow-up of 11.3 ± 9.4 years, the predominant arrhythmia pattern was paroxysmal in 62.3%, persistent in 28.2%, and permanent in 9.5%. Permanent atrial arrhythmias increased with age from 3.1% to 22.6% in patients <20 years to ≥50 years, respectively (p < 0.0001). IART is the most common presenting atrial arrhythmia in patients with congenital heart disease, with a predominantly paroxysmal pattern. However, atrial fibrillation increases in prevalence and atrial arrhythmias progressively become permanent as the population ages. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hill, D.A.
1989-01-01
The aim of this thesis was to investigate the acute autonomic effects of the Transcendental Meditation Program (TM) and resolve the conflict arising from discrepant neurochemical and psychophysiological data. Three experimental investigations were performed. The first examined beta{sub 2}-adrenergic receptors (AR's) on peripheral blood lymphocytes, via (I{sup 125})iodocyanopindolol binding, in 10 male mediating and 10 age matched non-meditating control subjects, to test the hypothesis that the long-term practice of TM and the TM Sidhi Program (TMSP) reduces end organ sensitivity to adrenergic agonists. The second investigated respiratory sinus arrhythmia (an indirect measure of cardiac Parasympathetic Nervous System tone), and skinmore » resistance (a measure of Sympathetic Nervous System tone) during periods of spontaneous respiratory apneusis, a phenomenon occurring during TM that is known to mark the subjective experience of transcending. The third was within subject investigation of the acute effects of the TMSP on 5-hydroxytryptamine (5-HT) activity. Platelet 5-HT was assayed by high pressure liquid chromatography with electrochemical detection, plasma prolactin (PL) and lutenizing hormone (LH) by radioimmunoassay, tryptophan by spectrofluorimetry, and alpha-1-acid glycoprotein (AGP, a modulator of 5-HT uptake) by radial immunodiffusion assay.« less
Emotion regulation and mania risk: Differential responses to implicit and explicit cues to regulate.
Ajaya, Yatrika; Peckham, Andrew D; Johnson, Sheri L
2016-03-01
People prone to mania use emotion regulation (ER) strategies well when explicitly coached to do so in laboratory settings, but they find these strategies ineffective in daily life. We hypothesized that, compared with control participants, mania-prone people would show ER deficits when they received implicit, but not explicit, cues to use ER. Undergraduates (N = 66) completed the Hypomanic Personality Scale (HPS) and were randomly assigned to one of three experimental conditions: automatic ER (scrambled sentence primes), deliberate ER (verbal instructions), or control (no priming or instructions to use ER). Then, participants played a videogame designed to evoke anger. Emotion responses were measured with a multi-modal assessment of self-reported affect, psychophysiology, and facial expressions. Respiratory sinus arrhythmia (RSA) was used to index ER. The videogame effectively elicited subjective anger, angry facial expressions, and heart rate increases when keys malfunctioned. As hypothesized, persons who were more mania prone showed greater RSA increases in the deliberate ER condition than in the automatic or control conditions. One potential limitation is the use of an analog sample. Findings suggest that those at risk for mania require more explicit instruction to engage ER effectively. Copyright © 2015 Elsevier Ltd. All rights reserved.
Fisher, Aaron J; Reeves, Jonathan W; Chi, Cyrus
2016-07-01
Expanding on recently published methods, the current study presents an approach to estimating the dynamic, regulatory effect of the parasympathetic nervous system on heart period on a moment-to-moment basis. We estimated second-to-second variation in respiratory sinus arrhythmia (RSA) in order to estimate the contemporaneous and time-lagged relationships among RSA, interbeat interval (IBI), and respiration rate via vector autoregression. Moreover, we modeled these relationships at lags of 1 s to 10 s, in order to evaluate the optimal latency for estimating dynamic RSA effects. The IBI (t) on RSA (t-n) regression parameter was extracted from individual models as an operationalization of the regulatory effect of RSA on IBI-referred to as dynamic RSA (dRSA). Dynamic RSA positively correlated with standard averages of heart rate and negatively correlated with standard averages of RSA. We propose that dRSA reflects the active downregulation of heart period by the parasympathetic nervous system and thus represents a novel metric that provides incremental validity in the measurement of autonomic cardiac control-specifically, a method by which parasympathetic regulatory effects can be measured in process. © 2016 Society for Psychophysiological Research.
Cui, Lixian; Morris, Amanda Sheffield; Harrist, Amanda W.; Larzelere, Robert E.; Criss, Michael M.; Houltberg, Benjamin J.
2015-01-01
The current study examined associations between adolescent respiratory sinus arrhythmia (RSA) during an angry event discussion task and adolescents’ emotion regulation and adjustment. Data were collected from 206 adolescents (10–18 years old, M age = 13.37). Electrocardiogram (ECG) and respiration data were collected from adolescents, and RSA values and respiration rates were computed. Adolescents reported on their own emotion regulation, prosocial behavior, and aggressive behavior. Multi-level latent growth modeling was employed to capture RSA responses across time (i.e., linear and quadratic changes; time course approach), and adolescent emotion regulation and adjustment variables were included in the model to test their links to RSA responses. Results indicated that high RSA baseline was associated with more adolescent prosocial behavior. A pattern of initial RSA decreases (RSA suppression) in response to angry event recall and subsequent RSA increases (RSA rebound) were related to better anger and sadness regulation and more prosocial behavior. However, RSA was not significantly linked to adolescent aggressive behavior. We also compared the time course approach with the conventional linear approach and found that the time course approach provided more meaningful and rich information. The implications of adaptive RSA change patterns are discussed. PMID:25642723
Sex Differences in Autonomic Correlates of Conduct Problems and Aggression
BEAUCHAINE, THEODORE P.; HONG, JAMES; MARSH, PENNY
2009-01-01
Objective To examine sex differences in autonomic nervous system functioning in children and adolescents with conduct problems and to evaluate the role of aggression in predicting autonomic nervous system functioning, over and above the effects of disruptive behavior. Although deficiencies in autonomic responding among boys with oppositional defiant disorder and/or conduct disorder are well documented, it remains unclear whether such findings extend to girls or apply only to children with aggressive forms of conduct problems. Method Electrodermal responding, cardiac pre-ejection period, and respiratory sinus arrhythmia were recorded while boys (n = 110; 53 with conduct problems, 57 controls) and girls (n = 65; 33 with conduct problems, 32 controls) between the ages of 8 and 12 sat for an extended baseline, then played a game with conditions of reward and frustrative nonreward. Results Both sex effects and aggression effects were found. Aggressive boys with conduct problems demonstrated reduced autonomic functioning, consistent with previous research. In contrast, aggressive girls with conduct problems exhibited greater electrodermal responding than controls, with no differences in cardiovascular reactivity to incentives. Conclusions Observed sex differences in the autonomic correlates of conduct problems and aggression may suggest different etiological mechanisms of externalizing psychopathology for girls compared with boys. PMID:18520959
Pang, Karen C.; Beauchaine, Theodore P.
2012-01-01
Conduct disorder (CD) and depression co-occur at far greater levels than chance, despite largely separate diagnostic criteria. One potential shared mechanism of this comorbidity is emotion dysregulation, which characterizes both internalizing and externalizing disorders. Previous research demonstrates that respiratory sinus arrhythmia (RSA)—a peripheral biomarker of emotion regulation—is attenuated among children with CD, and among children with depression. However, few studies have examined biomarkers of emotion regulation as a function of heterotypic comorbidity. We evaluated longitudinal patterns of RSA and RSA reactivity to emotion evocation across three annual assessments among 207 children diagnosed at ages 8–12 years with CD (n=30), depression (n=28), comorbid CD and depression (n=80), or no psychiatric condition (n=69). Using continuous symptom counts as predictors, Depression × CD interactions were observed for both Time 1 resting RSA and Time 1 RSA reactivity. Conduct disorder, depression, and their interaction were all associated with low resting RSA at Time 1. In addition, concurrently elevated CD and depression scores predicted the greatest RSA reactivity to emotion evocation. Psychopathology scores were unrelated to developmental changes in RSA and RSA reactivity over time. PMID:22826111
von Bonin, Dietrich; Grote, Vincent; Buri, Caroline; Cysarz, Dirk; Heusser, Peter; Moser, Max; Wolf, Ursula; Laederach, Kurt
2014-11-30
Heart rate and breathing rate fluctuations represent interacting physiological oscillations. These interactions are commonly studied using respiratory sinus arrhythmia (RSA) of heart rate variability (HRV) or analyzing cardiorespiratory synchronization. Earlier work has focused on a third type of relationship, the temporal ratio of respiration rate and heart rate (HRR). Each method seems to reveal a specific aspect of cardiorespiratory interaction and may be suitable for assessing states of arousal and relaxation of the organism. We used HRR in a study with 87 healthy subjects to determine the ability to relax during 5 day-resting periods in comparison to deep sleep relaxation. The degree to which a person during waking state could relax was compared to somatic complaints, health-related quality of life, anxiety and depression. Our results show, that HRR is barely connected to balance (LF/HF) in HRV, but significantly correlates to the perception of general health and mental well-being as well as to depression. If relaxation, as expressed in HRR, during day-resting is near to deep sleep relaxation, the subjects felt healthier, indicated better mental well-being and less depressive moods. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
de Paola, A A; Balbão, C E; Castiglioni, M L; Barbieri, A; Mendonça, A; Netto, O S; Guiguer Júnior, N; Vattimo, A C; Souza, I A; Portugal, O P
1993-06-01
To localize the site of the origin of sustained ventricular tachycardia in chronic chagasic cardiomyopathy patients refractory to antiarrhythmic therapy by radionuclide angiography techniques. Five patients underwent radionuclide angiography by intravenous administration of 25mCi 99mTc. The images were obtained in sinus rhythm and during sustained ventricular tachycardia induced in the electrophysiologic laboratory for endocardial mapping. Amplitude and phase images were obtained resulting in a contraction wave synchronic to ventricular dispolarization. All patients had haemodynamic stability during the arrhythmia. One patient had incessant ventricular tachycardia. Mean ejection fraction was 0.38. In 4 patients the site of the origin of ventricular tachycardia was posterior and in one it was localized in the interventricular septum. There was identity in the site of the origin of ventricular tachycardia obtained by endocardial mapping or radionuclide angiography in all patients. The therapy was chemical ablation in 3 patients, surgical aneurysmectomy in one and pharmacologic therapy in the last patient. The site of the origin of ventricular tachycardia can be estimated by analyzing the contraction wave obtained by radionuclide angiography techniques in patients with hemodynamic stable sustained ventricular tachycardia.
Closing the Gap between the Inside and the Outside: Interoceptive Sensitivity and Social Distances
Ambrosecchia, Marianna; Gallese, Vittorio
2013-01-01
Humans’ ability to represent their body state from within through interoception has been proposed to predict different aspects of human cognition and behaviour. We focused on the possible contribution of interoceptive sensitivity to social behaviour as mediated by adaptive modulation of autonomic response. We, thus, investigated whether interoceptive sensitivity to one's heartbeat predicts participants' autonomic response at different social distances. We measured respiratory sinus arrhythmia (RSA) during either a Social or a Non-social task. In the Social task each participant viewed an experimenter performing a caress-like movement at different distances from their hand. In the Non-social task a metal stick was moved at the same distances from the participant's hand. We found a positive association between interoceptive sensitivity and autonomic response only for the social setting. Moreover, only good heartbeat perceivers showed higher autonomic response 1) in the social compared to the non-social setting, 2) specifically, when the experimenter's hand was moving at boundary of their peripersonal space (20 cm from the participant's hand). Our findings suggest that interoceptive sensitivity might contribute to interindividual differences concerning social attitudes and interpersonal space representation via recruitment of different adaptive autonomic response strategies. PMID:24098397
Opioid microinjection into raphe magnus modulates cardiorespiratory function in mice and rats.
Hellman, Kevin M; Mendelson, Scott J; Mendez-Duarte, Marco A; Russell, James L; Mason, Peggy
2009-11-01
The raphe magnus (RM) participates in opioid analgesia and contains pain-modulatory neurons with respiration-related discharge. Here, we asked whether RM contributes to respiratory depression, the most prevalent lethal effect of opioids. To investigate whether opioidergic transmission in RM produces respiratory depression, we microinjected a mu-opioid receptor agonist, DAMGO, or morphine into the RM of awake rodents. In mice, opioid microinjection produced sustained decreases in respiratory rate (170 to 120 breaths/min), as well as heart rate (520 to 400 beats/min). Respiratory sinus arrhythmia, indicative of enhanced parasympathetic activity, was prevalent in mice receiving DAMGO microinjection. We performed similar experiments in rats but observed no changes in breathing rate or heart rate. Both rats and mice experienced significantly more episodes of bradypnea, indicative of impaired respiratory drive, after opioid microinjection. During spontaneous arousals, rats showed less tachycardia after opioid microinjection than before microinjection, suggestive of an attenuated sympathetic tone. Thus, activation of opioidergic signaling within RM produces effects beyond analgesia, including the unwanted destabilization of cardiorespiratory function. These adverse effects on homeostasis consequent to opioid microinjection imply a role for RM in regulating the balance of sympathetic and parasympathetic tone.
Human sinus arrhythmia as an index of vagal cardiac outflow
NASA Technical Reports Server (NTRS)
Eckberg, D. L.
1983-01-01
The human central vagal mechanisms were investigated by measuring the intervals between heartbeats during controlled breathing (at breathing intervals of 2.5-10 s and nominal tidal volumes of 1000 and 1500 ml) in six young men and women. It was found that as the breathing interval increased, the longest heart periods became longer, the shortest heart periods became shorter, and the peak-valley P-P intervals increased asymptotically. Peak-valley intervals also increased in proportion to tidal volume, although this influence was small. The phase angles between heart period changes and respiration were found to vary as linear functions of breathing interval. Heart period shortening began in inspiration at short breathing intervals and in expiration at long breathing intervals, while heart period lengthening began in early expiration at all breathing intervals studied. It is concluded that a close relationship exists between variations of respiratory depth and interval and the quantity, periodicity, and timing of vagal cardiac outflow in conscious humans. The results indicate that at usual breathing rates, phasic respiration-related changes of vagal motoneuron activity begin in expiration, progress slowly, and are incompletely expressed at fast breathing ratges.
Exercise-induced syncope in a 22-year-old man.
Yeo, Colin; Tan, Vern Hsen; Wong, Kelvin Ck
2017-04-01
A 22-year-old man was referred to us for syncope during a game of Captain's ball. There was no prodrome. His friends did not notice any ictal movements. He was otherwise well prior to passing out. He was not taking any medications or supplements. He was not usually physically active, but was otherwise well with no significant medical history. This is his first episode of syncope. There was no history of cardiac arrest or seizures. There is no family history of premature sudden cardiac death.Physical examination was normal. ECG at rest demonstrated sinus rhythm with corrected QT interval of 400 ms. Echocardiography revealed a structurally normal heart. Holter monitoring was normal. Treadmill exercise stress test demonstrated the following rhythm on figure 1 during stage 4 Bruce protocol. Stress test was terminated in view of sustained arrhythmia as illustrated. He felt light-headed during the period, but otherwise felt that he could carry on with the exercise. ECG during recovery was unremarkable. 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/.
Zena, Lucas A; Leite, Cléo A C; Longhini, Leonardo S; Dias, Daniel P M; da Silva, Glauber S F; Hartzler, Lynn K; Gargaglioni, Luciane H; Bícego, Kênia C
2017-11-23
Beat-to-beat variation in heart rate (f H ) has been used as a tool for elucidating the balance between sympathetic and parasympathetic modulation of the heart. A portion of the temporal changes in f H is evidenced by a respiratory influence (cardiorespiratory interaction) on heart rate variability (HRV) with heartbeats increasing and decreasing within a respiratory cycle. Nevertheless, little is known about respiratory effects on HRV in lower vertebrates. By using frequency domain analysis, we provide the first evidence of a ventilatory component in HRV similar to mammalian respiratory sinus arrhythmia in an amphibian, the toad Rhinella schneideri. Increases in the heartbeats arose synchronously with each lung inflation cycle, an intermittent breathing pattern comprised of a series of successive lung inflations. A well-marked peak in the HRV signal matching lung inflation cycle was verified in toads whenever lung inflation cycles exhibit a regular rhythm. The cardiac beat-to-beat variation evoked at the moment of lung inflation accounts for both vagal and sympathetic influences. This cardiorespiratory interaction may arise from interactions between central and peripheral feedback mechanisms governing cardiorespiratory control and may underlie important cardiorespiratory adjustments for gas exchange improvement especially under extreme conditions like low oxygen availability.
Activity of cardiorespiratory networks revealed by transsynaptic virus expressing GFP.
Irnaten, M; Neff, R A; Wang, J; Loewy, A D; Mettenleiter, T C; Mendelowitz, D
2001-01-01
A fluorescent transneuronal marker capable of labeling individual neurons in a central network while maintaining their normal physiology would permit functional studies of neurons within entire networks responsible for complex behaviors such as cardiorespiratory reflexes. The Bartha strain of pseudorabies virus (PRV), an attenuated swine alpha herpesvirus, can be used as a transsynaptic marker of neural circuits. Bartha PRV invades neuronal networks in the CNS through peripherally projecting axons, replicates in these parent neurons, and then travels transsynaptically to continue labeling the second- and higher-order neurons in a time-dependent manner. A Bartha PRV mutant that expresses green fluorescent protein (GFP) was used to visualize and record from neurons that determine the vagal motor outflow to the heart. Here we show that Bartha PRV-GFP-labeled neurons retain their normal electrophysiological properties and that the labeled baroreflex pathways that control heart rate are unaltered by the virus. This novel transynaptic virus permits in vitro studies of identified neurons within functionally defined neuronal systems including networks that mediate cardiovascular and respiratory function and interactions. We also demonstrate superior laryngeal motorneurons fire spontaneously and synapse on cardiac vagal neurons in the nucleus ambiguus. This cardiorespiratory pathway provides a neural basis of respiratory sinus arrhythmias.
Evidence for sex differences in fetal programming of physiological stress reactivity in infancy.
Tibu, Florin; Hill, Jonathan; Sharp, Helen; Marshall, Kate; Glover, Vivette; Pickles, Andrew
2014-11-01
Associations between low birth weight and prenatal anxiety and later psychopathology may arise from programming effects likely to be adaptive under some, but not other, environmental exposures and modified by sex differences. If physiological reactivity, which also confers vulnerability or resilience in an environment-dependent manner, is associated with birth weight and prenatal anxiety, it will be a candidate to mediate the links with psychopathology. From a general population sample of 1,233 first-time mothers recruited at 20 weeks gestation, a sample of 316 stratified by adversity was assessed at 32 weeks and when their infants were aged 29 weeks (N = 271). Prenatal anxiety was assessed by self-report, birth weight from medical records, and vagal reactivity from respiratory sinus arrhythmia during four nonstressful and one stressful (still-face) procedure. Lower birth weight for gestational age predicted higher vagal reactivity only in girls (interaction term, p = .016), and prenatal maternal anxiety predicted lower vagal reactivity only in boys (interaction term, p = .014). These findings are consistent with sex differences in fetal programming, whereby prenatal risks are associated with increased stress reactivity in females but decreased reactivity in males, with distinctive advantages and penalties for each sex.
Behavior Problems among Cocaine Exposed Children: Role of Physiological Regulation and Parenting
Finger, Brent; Schuetze, Pamela; Eiden, Rina D.
2014-01-01
This study examined interrelations between prenatal cocaine exposure, child autonomic regulation, parenting behavior and child sex on parent-reported behavior problems at 36 months of age. We hypothesized that respiratory sinus arrhythmia (RSA)1 at 13 months of age would mediate the relation between cocaine exposure and behavior problems. We also hypothesized that child sex, maternal negative affect, and maternal sensitivity observed at 13 months of age would moderate the relation between RSA and behavior problems. Results revealed that cocaine exposure predicted low baseline RSA and low RSA withdrawal during a negative affect task. Low baseline RSA, in turn, predicted fewer behavior problems offering support for an indirect association between cocaine exposure and behavior problems. The association between baseline RSA and behavior problems was further moderated by maternal negative affect such that high baseline RSA was more strongly related to behavior problems under conditions of high compared to low maternal negative affect. Results also revealed a near significant trend for baseline RSA to be more strongly related to behavior problems among boys than girls. These findings highlight several possible pathways toward behavior problems among cocaine exposed children. PMID:24480789
Hoffman, Elizabeth R.; Hodges, Eric A.; Propper, Cathi; Postage, Pamela L.; Zipkin, Elana C.; Bentley, Margaret E.; Ward, Dianne S.; Hamer, Robert M.; Bulik, Cynthia M.
2013-01-01
The aim of this pilot project was to describe maternal responsiveness during child feeding in mothers with eating disorder histories through the combined use of observational, self-report, and physiologic methods. For this non-randomized cohort pilot study, 25 mothers with histories of eating disorders and 25 mothers with no history of an eating disorder with children ages 6–36 months were selected such that the groups were similar based on child age group (within 6 months) and child sex. Maternal behavioral responsiveness to child cues was assessed by video-recording and behavioral coding of both a free-play and feeding episode. Physiologic engagement was assessed through measurement of respiratory sinus arrhythmia (RSA) reactivity during free-play and feeding episodes. No differences were detected in observed behavioral responsiveness during feeding or free-play in mothers with eating disorder histories compared with controls. Mothers with eating disorder histories did report more parenting stress, increased anxiety, and exhibited a blunted physiologic stress response (less RSA reactivity) during both feeding and free-play interactions with their children. These results support future larger-scale investigations of RSA reactivity in mothers with eating disorders. PMID:24511180
Sterling, Mark; Huang, David T; Ghoraani, Behnaz
2015-01-01
We propose a new algorithm to predict the outcome of direct-current electric (DCE) cardioversion for atrial fibrillation (AF) patients. AF is the most common cardiac arrhythmia and DCE cardioversion is a noninvasive treatment to end AF and return the patient to sinus rhythm (SR). Unfortunately, there is a high risk of AF recurrence in persistent AF patients; hence clinically it is important to predict the DCE outcome in order to avoid the procedure's side effects. This study develops a feature extraction and classification framework to predict AF recurrence patients from the underlying structure of atrial activity (AA). A multiresolution signal decomposition technique, based on matching pursuit (MP), was used to project the AA over a dictionary of wavelets. Seven novel features were derived from the decompositions and were employed in a quadratic discrimination analysis classification to predict the success of post-DCE cardioversion in 40 patients with persistent AF. The proposed algorithm achieved 100% sensitivity and 95% specificity, indicating that the proposed computational approach captures detailed structural information about the underlying AA and could provide reliable information for effective management of AF.
Silvia, Paul J.; Nusbaum, Emily C.; Eddington, Kari M.; Beaty, Roger E.; Kwapil, Thomas R.
2014-01-01
Motivational approaches to depression emphasize the role of dysfunctional motivational dynamics, particularly diminished reward and incentive processes associated with anhedonia. A study examined how anhedonic depressive symptoms, measured continuously across a wide range of severity, influenced the physiological mobilization of effort during a cognitive task. Using motivational intensity theory as a guide, we expected that the diminished incentive value associated with anhedonic depressive symptoms would reduce effort during a “do your best” challenge (also known as an unfixed or self-paced challenge), in which effort is a function of the value of achieving the task’s goal. Using impedance cardiography, two cardiac autonomic responses were assessed: pre-ejection period (PEP), a measure of sympathetic activity and our primary measure of interest, and respiratory sinus arrhythmia (RSA), a measure of parasympathetic activity. As expected, PEP slowed from baseline to task as anhedonic depressive symptoms increased (as measured with the DASS Depression scale), indicating diminished effort-related sympathetic activity. No significant effects appeared for RSA. The findings support motivational intensity theory as a translational model of effort processes in depression and clarify some inconsistent effects of depressive symptoms on effort-related physiology found in past work. PMID:25431505
Ferrer, Ana; Sebastián, Rafael; Sánchez-Quintana, Damián; Rodríguez, José F.; Godoy, Eduardo J.; Martínez, Laura; Saiz, Javier
2015-01-01
Atrial arrhythmias, and specifically atrial fibrillation (AF), induce rapid and irregular activation patterns that appear on the torso surface as abnormal P-waves in electrocardiograms and body surface potential maps (BSPM). In recent years both P-waves and the BSPM have been used to identify the mechanisms underlying AF, such as localizing ectopic foci or high-frequency rotors. However, the relationship between the activation of the different areas of the atria and the characteristics of the BSPM and P-wave signals are still far from being completely understood. In this work we developed a multi-scale framework, which combines a highly-detailed 3D atrial model and a torso model to study the relationship between atrial activation and surface signals in sinus rhythm. Using this multi scale model, it was revealed that the best places for recording P-waves are the frontal upper right and the frontal and rear left quadrants of the torso. Our results also suggest that only nine regions (of the twenty-one structures in which the atrial surface was divided) make a significant contribution to the BSPM and determine the main P-wave characteristics. PMID:26523732
Dynamic changes in parent affect and adolescent cardiac vagal regulation: a real-time analysis.
Cui, Lixian; Morris, Amanda Sheffield; Harrist, Amanda W; Larzelere, Robert E; Criss, Michael M
2015-04-01
The current study explored the role of parents' negative and positive affect in adolescent respiratory sinus arrhythmia (RSA) reactivity during a parent-adolescent conflict discussion task and the moderating effects of adolescent sex and age. Questionnaire data were collected from 206 adolescents (10-18 years of age; M = 13.37 years) and their primary caregivers (83.3% biological mothers). Electrocardiogram and respiration data were collected from adolescents, and RSA variables were computed. Parent affect was coded during the conflict discussion task. Multilevel modeling was used to distinguish the between- and within-individual effects of parent affect on adolescent RSA. Results indicated that observed within-parent-teen dyad anger was negatively associated with adolescent RSA, controlling for previous-minute RSA level, particularly among adolescents 13 years and older. In addition, observed between-dyad positive affect was positively linked to RSA for both boys and girls when previous-minute RSA level was controlled. Within-dyad positive affect was positively related to girl's RSA only. These findings suggest that expressions of positive affect may be related to better vagal regulation (RSA increases), whereas expressions of anger may be related to poor vagal regulation (RSA decreases) during social engagement. (c) 2015 APA, all rights reserved).
Wenxin Keli for atrial fibrillation
He, Zhuogen; Zheng, Minan; Xie, Pingchang; Wang, Yuanping; Yan, Xia; Deng, Dingwei
2018-01-01
Abstract Background: Atrial fibrillation (AF) is a most common cardiac arrhythmia in clinical practice. In China, Wenxin Keli (WXKL) therapy is a common treatment for AF, but its effects and safety remain uncertain. This protocol is to provide the methods used to assess the effectiveness and safety of WXKL for the treatment of patients with AF. Methods: We will search comprehensively the 4 English databases EMBASE, the Cochrane Central Register of Controlled Trials (Cochrane Library), PubMed, and Medline and 3 Chinese databases China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), and Chinese Science and Technology Periodical database (VIP) on computer on March 2018 for the randomized controlled trials (RCTs) regarding WXKL for AF. The therapeutic effects according to the sinus rhythm and p-wave dispersion (Pwd) will be accepted as the primary outcomes. We will use RevMan V.5.3 software as well to compute the data synthesis carefully when a meta-analysis is allowed. Results: This study will provide a high-quality synthesis of current evidence of WXKL for AF. Conclusion: The conclusion of our systematic review will provide evidence to judge whether WXKL is an effective intervention for patient with AF. PROSPERO registration number: PROSPERO CRD 42018082045. PMID:29702984
Social power facilitates the effect of prosocial orientation on empathic accuracy.
Côté, Stéphane; Kraus, Michael W; Cheng, Bonnie Hayden; Oveis, Christopher; van der Löwe, Ilmo; Lian, Hua; Keltner, Dacher
2011-08-01
Power increases the tendency to behave in a goal-congruent fashion. Guided by this theoretical notion, we hypothesized that elevated power would strengthen the positive association between prosocial orientation and empathic accuracy. In 3 studies with university and adult samples, prosocial orientation was more strongly associated with empathic accuracy when distinct forms of power were high than when power was low. In Study 1, a physiological indicator of prosocial orientation, respiratory sinus arrhythmia, exhibited a stronger positive association with empathic accuracy in a face-to-face interaction among dispositionally high-power individuals. In Study 2, experimentally induced prosocial orientation increased the ability to accurately judge the emotions of a stranger but only for individuals induced to feel powerful. In Study 3, a trait measure of prosocial orientation was more strongly related to scores on a standard test of empathic accuracy among employees who occupied high-power positions within an organization. Study 3 further showed a mediated relationship between prosocial orientation and career satisfaction through empathic accuracy among employees in high-power positions but not among employees in lower power positions. Discussion concentrates upon the implications of these findings for studies of prosociality, power, and social behavior.
Affective and physiological responses to the suffering of others: compassion and vagal activity.
Stellar, Jennifer E; Cohen, Adam; Oveis, Christopher; Keltner, Dacher
2015-04-01
Compassion is an affective response to another's suffering and a catalyst of prosocial behavior. In the present studies, we explore the peripheral physiological changes associated with the experience of compassion. Guided by long-standing theoretical claims, we propose that compassion is associated with activation in the parasympathetic autonomic nervous system through the vagus nerve. Across 4 studies, participants witnessed others suffer while we recorded physiological measures, including heart rate, respiration, skin conductance, and a measure of vagal activity called respiratory sinus arrhythmia (RSA). Participants exhibited greater RSA during the compassion induction compared with a neutral control (Study 1), another positive emotion (Study 2), and a prosocial emotion lacking appraisals of another person's suffering (Study 3). Greater RSA during the experience of compassion compared with the neutral or control emotion was often accompanied by lower heart rate and respiration but no difference in skin conductance. In Study 4, increases in RSA during compassion positively predicted an established composite of compassion-related words, continuous self-reports of compassion, and nonverbal displays of compassion. Compassion, a core affective component of empathy and prosociality, is associated with heightened parasympathetic activity. (c) 2015 APA, all rights reserved).
Sidek, Khairul; Khali, Ibrahim
2012-01-01
In this paper, a person identification mechanism implemented with Cardioid based graph using electrocardiogram (ECG) is presented. Cardioid based graph has given a reasonably good classification accuracy in terms of differentiating between individuals. However, the current feature extraction method using Euclidean distance could be further improved by using Mahalanobis distance measurement producing extracted coefficients which takes into account the correlations of the data set. Identification is then done by applying these extracted features to Radial Basis Function Network. A total of 30 ECG data from MITBIH Normal Sinus Rhythm database (NSRDB) and MITBIH Arrhythmia database (MITDB) were used for development and evaluation purposes. Our experimentation results suggest that the proposed feature extraction method has significantly increased the classification performance of subjects in both databases with accuracy from 97.50% to 99.80% in NSRDB and 96.50% to 99.40% in MITDB. High sensitivity, specificity and positive predictive value of 99.17%, 99.91% and 99.23% for NSRDB and 99.30%, 99.90% and 99.40% for MITDB also validates the proposed method. This result also indicates that the right feature extraction technique plays a vital role in determining the persistency of the classification accuracy for Cardioid based person identification mechanism.
Crowell, Sheila E; Baucom, Brian R; Yaptangco, Mona; Bride, Daniel; Hsiao, Ray; McCauley, Elizabeth; Beauchaine, Theodore P
2014-04-01
Many depressed adolescents experience difficulty in regulating their emotions. These emotion regulation difficulties appear to emerge in part from socialization processes within families and then generalize to other contexts. However, emotion dysregulation is typically assessed within the individual, rather than in the social relationships that shape and maintain dysregulation. In this study, we evaluated concordance of physiological and observational measures of emotion dysregulation during interpersonal conflict, using a multilevel actor-partner interdependence model (APIM). Participants were 75 mother-daughter dyads, including 50 depressed adolescents with or without a history of self-injury, and 25 typically developing controls. Behavior dysregulation was operationalized as observed aversiveness during a conflict discussion, and physiological dysregulation was indexed by respiratory sinus arrhythmia (RSA). Results revealed different patterns of concordance for control versus depressed participants. Controls evidenced a concordant partner (between-person) effect, and showed increased physiological regulation during minutes when their partner was more aversive. In contrast, clinical dyad members displayed a concordant actor (within-person) effect, becoming simultaneously physiologically and behaviorally dysregulated. Results inform current understanding of emotion dysregulation across multiple levels of analysis. Copyright © 2014 Elsevier B.V. All rights reserved.
Chen, Zhe; Purdon, Patrick L.; Brown, Emery N.; Barbieri, Riccardo
2012-01-01
In recent years, time-varying inhomogeneous point process models have been introduced for assessment of instantaneous heartbeat dynamics as well as specific cardiovascular control mechanisms and hemodynamics. Assessment of the model’s statistics is established through the Wiener-Volterra theory and a multivariate autoregressive (AR) structure. A variety of instantaneous cardiovascular metrics, such as heart rate (HR), heart rate variability (HRV), respiratory sinus arrhythmia (RSA), and baroreceptor-cardiac reflex (baroreflex) sensitivity (BRS), are derived within a parametric framework and instantaneously updated with adaptive and local maximum likelihood estimation algorithms. Inclusion of second-order non-linearities, with subsequent bispectral quantification in the frequency domain, further allows for definition of instantaneous metrics of non-linearity. We here present a comprehensive review of the devised methods as applied to experimental recordings from healthy subjects during propofol anesthesia. Collective results reveal interesting dynamic trends across the different pharmacological interventions operated within each anesthesia session, confirming the ability of the algorithm to track important changes in cardiorespiratory elicited interactions, and pointing at our mathematical approach as a promising monitoring tool for an accurate, non-invasive assessment in clinical practice. We also discuss the limitations and other alternative modeling strategies of our point process approach. PMID:22375120
Mertes, H; Sawada, S G; Ryan, T; Segar, D S; Kovacs, R; Foltz, J; Feigenbaum, H
1993-07-01
The use of dobutamine stress echocardiography for the evaluation of coronary artery disease is rapidly expanding. New applications of the technique are being investigated in a wide variety of patients including those with advanced coronary artery disease. Despite its widespread use, the safety of dobutamine stress echocardiography has not been sufficiently documented. A consecutive series of 1118 patients undergoing dobutamine stress echocardiography for evaluation of known or suspected coronary artery disease form the basis of this report. Dobutamine stress testing was performed for evaluation of chest pain, risk assessment before noncardiac surgery, after recent myocardial infarction, or as a part of ongoing research protocols. Over the study period, the maximal dose of dobutamine used was increased from 30 to 50 micrograms/kg per minute, and atropine was used in 420 (37%) patients. There were no occurrences of death, myocardial infarction, or episodes of sustained ventricular tachycardia as a result of dobutamine stress testing. The major reasons for test termination were achievement of target heart rate in 583 patients (52.1%), maximum dose in 255 (22.8%), and angina pectoris in 142 (13%). The test was terminated in 36 (3%) patients because of noncardiac side effects including nausea, anxiety, headache, tremor, and urgency. Angina pectoris occurred in 216 (19.3%) patients. Sublingual nitroglycerin, a short-acting beta-blocker, or both types of medication were administered in 80 of these patients for relief of angina pectoris. None required intravenous nitroglycerin. A total of 736 (65%) patients had stable sinus rhythm throughout the test. The most common arrhythmias were frequent premature ventricular complexes (six or more per minute) in 172 patients (15%), and frequent premature atrial complexes in 86 (8%). There were 40 patients with nonsustained ventricular tachycardia. None had symptoms associated with the tachycardia, and only one received specific pharmacological treatment to prevent recurrence of the arrhythmia after the test was terminated. The patients who were evaluated after recent myocardial infarction and those who received atropine did not have a higher frequency of ventricular tachycardia compared with those without recent infarction and those not receiving atropine. Dobutamine stress echocardiography was safely performed using supplemental atropine and an aggressive dosing protocol. Noncardiac side effects were usually minor. Arrhythmias were well tolerated and rarely required treatment. In this study, serious complications from myocardial ischemia did not occur. Symptomatic ischemia was effectively treated with test termination, sublingual nitroglycerin, or short-acting beta-blockers.
Cavernous sinus thrombosis caused by contralateral sphenoid sinusitis: a case report
2013-01-01
Objective To report a rare case of unilateral cavernous sinus thrombosis caused by contralateral sphenoid sinusitis. Case report A 33-year-old female visited our hospital for severe, right-sided, temporal headache, chemosis, periorbital edema, and proptosis. These signs were associated with congested erythematous nasal mucosa with purulent discharge from the right superior nasal meatus. Contrast enhanced CT showed dilated left superior ophthalmic vein, suggestive of thrombosis, contrast enhancement of the left cavernous sinuses, and dilation of cavernous sinus, indicating cavernous sinus inflammation. The right maxillary, ethmoid and sphenoid sinuses showed mucosal thickening and retention of purulent material. She was diagnosed with cavernous sinus thrombosis caused by contralateral sphenoid sinusitis. All clinical symptoms and signs improved after endoscopic sphenoidotomy and appropriate medical treatment. Conclusions Sphenoiditis can cause contralateral cavernous sinus thrombosis. Early surgical sphenoidotomy and aggressive medical treatment are the cornerstones of successful management of this life-threatening complication. PMID:23497466