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American Journal of Obstetrics and... Apr 2000Irregular fetal heart rhythms are common in clinical practice, but there is little information available on their significance or appropriate management.
OBJECTIVE
Irregular fetal heart rhythms are common in clinical practice, but there is little information available on their significance or appropriate management.
STUDY DESIGN
This was a retrospective review of fetuses seen during 10 years that either were referred for fetal echocardiography because of a fetal arrhythmia or were found incidentally to have an arrhythmia during fetal echocardiography for other indications.
RESULTS
From 1988 through 1997 we performed 5566 fetal echocardiograms on 4838 different fetuses. There were 614 fetuses with irregular fetal heart rhythms. Among 595 referred for arrhythmias, extrasystoles were found in 255 (42.9%), normal rhythms were seen in 330 (55.4%), and hemodynamically significant arrhythmias were seen in 10. There were 2 fetuses with arrhythmias and structural heart disease. Nine of 10 fetuses with hemodynamically significant arrhythmias survived. An additional five neonates were found to have hemodynamically significant arrhythmias only postnatally. A total of 15 fetuses (2. 4%) among those referred for irregular rhythms had significant arrhythmias.
CONCLUSIONS
Irregular fetal heart rhythms signify hemodynamically significant arrhythmias in a small but important proportion of fetuses. Those without persistent irregularities on evaluation can be followed up with routine prenatal care.
Topics: Arrhythmias, Cardiac; Echocardiography; Female; Heart Rate, Fetal; Hemodynamics; Humans; Infant, Newborn; Pregnancy; Retrospective Studies; Ultrasonography, Prenatal
PubMed: 10764457
DOI: 10.1016/s0002-9378(00)70330-9 -
Physiological Measurement Mar 2023Assessment of heartbeat dynamics provides a promising framework for non-invasive monitoring of cardiovascular and autonomic states. Nevertheless, the non-specificity of...
Assessment of heartbeat dynamics provides a promising framework for non-invasive monitoring of cardiovascular and autonomic states. Nevertheless, the non-specificity of such measurements among clinical populations and healthy conditions associated with different autonomic states severely limits their applicability and exploitation in naturalistic conditions. This limitation arises especially when pathological or postural change-related sympathetic hyperactivity is compared to autonomic changes across age and experimental conditions. In this frame, we investigate the intrinsic irregularity and complexity of cardiac sympathetic and vagal activity series in different populations, which are associated with different cardiac autonomic dynamics. Sample entropy, fuzzy entropy, and distribution entropy are calculated on the recently proposed sympathetic and parasympathetic activity indices (SAI and PAI) series, which are derived from publicly available heartbeat series of congestive heart failure patients, elderly and young subjects watching a movie in the supine position, and healthy subjects undergoing slow postural changes. Results show statistically significant differences between pathological/old subjects and young subjects in the resting state and during slow tilt, with interesting trends in SAI- and PAI-related entropy values. Moreover, while CHF patients and healthy subjects in upright position show the higher cardiac sympathetic activity, elderly and young subjects in resting state showed higher vagal activity. We conclude that quantification of intrinsic cardiac complexity from sympathetic and vagal dynamics may provide new physiology insights and improve on the non-specificity of heartbeat-derived biomarkers.
Topics: Humans; Aged; Autonomic Nervous System; Vagus Nerve; Heart; Cardiovascular System; Heart Rate
PubMed: 36787644
DOI: 10.1088/1361-6579/acbc07 -
Journal of Cardiovascular... Feb 2015
Topics: Adrenergic beta-1 Receptor Antagonists; Anti-Arrhythmia Agents; Atrial Fibrillation; Calcium Channel Blockers; Female; Heart Conduction System; Heart Rate; Humans; Male
PubMed: 25431209
DOI: 10.1111/jce.12590 -
Journal of the Hawaii Dental Association Aug 1976
Topics: Dental Care; Heart; Humans; Pulse
PubMed: 1072214
DOI: No ID Found -
Journal of Affective Disorders May 2022Measures for the irregularity of the heartbeat, for example respiratory sinus arrhythmia, have been implicated as a measure for restorative functions of the vegetative... (Observational Study)
Observational Study
BACKGROUND
Measures for the irregularity of the heartbeat, for example respiratory sinus arrhythmia, have been implicated as a measure for restorative functions of the vegetative nervous system.
METHODS
In the current observational study, we investigated 265 subjects, 70 of whom had a lifetime history of major depression, with a plethysmographic heartbeat monitor, blood sampling, as well as a range of psychiatric questionnaires.
RESULTS
Subjects with a history of MDE had significantly reduced respiratory sinus arrhythmia (RSA) as compared to never-depressed controls; in the whole sample, higher RSA went with lower anxiety/fear variables, especially in subscores related to cardiac symptoms as well as being afraid of dying. A reduced RSA was also associated with an increased concentration of cytokines (TNFa, IL1a, IL6, IFNg) and thyroid-stimulating hormone in the serum, pointing to a possible triangular relationship between immune system, vegetative nervous system, and emotional dysregulation.
LIMITATIONS
We used a plethysmographic device for the measurement of heartbeat instead of an electrocardiogram, and had a single time point only.
CONCLUSIONS
This data corroborate the idea that a disequilibrium of the vegetative nervous, especially if accompanied by a dysregulation system in immune function, can increase the risk for depression. Conversely, vagal stimulation and anti-inflammatory treatments may support the treatment with antidepressants.
Topics: Arrhythmia, Sinus; Autonomic Nervous System; Depressive Disorder, Major; Heart Rate; Humans; Respiratory Sinus Arrhythmia
PubMed: 35196535
DOI: 10.1016/j.jad.2022.02.017 -
Chronobiology International Sep 1997The study of biological rhythms has always been a highly interdisciplinary field of research, one that is constantly breaking new ground. Developments during the past 10... (Review)
Review
The study of biological rhythms has always been a highly interdisciplinary field of research, one that is constantly breaking new ground. Developments during the past 10 years are transforming our ideas about the dynamics of physiological regulation in two ways: (i) homeostasis is really homeodynamics, with sophisticated but robust patterns of hierarchically nested rhythms covering several orders of magnitude in the frequency domain; (ii) there is much more irregularity than previously believed in processes as basic as the heart rate, suggesting either a chaotic generator, a complex pattern of interacting systems with different frequencies, or possibly both. This behavior is consistent with that expected of organisms as complex adaptive systems.
Topics: Acclimatization; Activity Cycles; Adaptation, Physiological; Animals; Circadian Rhythm; Heart Rate; Homeostasis; Humans; Models, Biological; Periodicity
PubMed: 9298288
DOI: 10.3109/07420529709001474 -
International Journal of Environmental... Feb 2022Heart disease, caused by low heart rate, is one of the most significant causes of mortality in the world today. Therefore, it is critical to monitor heart health by...
Heart disease, caused by low heart rate, is one of the most significant causes of mortality in the world today. Therefore, it is critical to monitor heart health by identifying the deviation in the heart rate very early, which makes it easier to detect and manage the heart's function irregularities at a very early stage. The fast-growing use of advanced technology such as the Internet of Things (IoT), wearable monitoring systems and artificial intelligence (AI) in the healthcare systems has continued to play a vital role in the analysis of huge amounts of health-based data for early and accurate disease detection and diagnosis for personalized treatment and prognosis evaluation. It is then important to analyze the effectiveness of using data analytics and machine learning to monitor and predict heart rates using wearable device (accelerometer)-generated data. Hence, in this study, we explored a number of powerful data-driven models including the autoregressive integrated moving average (ARIMA) model, linear regression, support vector regression (SVR), k-nearest neighbor (KNN) regressor, decision tree regressor, random forest regressor and long short-term memory (LSTM) recurrent neural network algorithm for the analysis of accelerometer data to make future HR predictions from the accelerometer's univariant HR time-series data from healthy people. The performances of the models were evaluated under different durations. Evaluated on a very recently created data set, our experimental results demonstrate the effectiveness of using an ARIMA model with a walk-forward validation and linear regression for predicting heart rate under all durations and other models for durations longer than 1 min. The results of this study show that employing these data analytics techniques can be used to predict future HR more accurately using accelerometers.
Topics: Artificial Intelligence; Heart Rate; Humans; Machine Learning; Neural Networks, Computer; Wearable Electronic Devices
PubMed: 35206603
DOI: 10.3390/ijerph19042417 -
Journal of Cardiovascular... Dec 2022Atrial fibrillation (AF) is the most common sustained arrhythmia in humans. The onset of the arrhythmia can significantly impair cardiac function. This hemodynamic...
INTRODUCTION
Atrial fibrillation (AF) is the most common sustained arrhythmia in humans. The onset of the arrhythmia can significantly impair cardiac function. This hemodynamic deterioration has been explained by several mechanisms such as the loss of atrial contraction, shortening of ventricular filling, or heart rhythm irregularity. This study sought to evaluate the relative hemodynamic contribution of each of these components during in vivo simulated human AF.
METHODS
Twelve patients undergoing catheter ablation for paroxysmal AF were paced simultaneously from the proximal coronary sinus and the His bundle region according to prescribed sequences of irregular R-R intervals with the average rate of 90 and 130 bpm, which were extracted from the database of digital ECG recordings of AF from other patients. The simulated AF was compared to regular atrial pacing with spontaneous atrioventricular conduction and regular simultaneous atrioventricular pacing at the same heart rate. Beat-by-beat left atrial and left ventricular pressures, including LV dP/dT and Tau index were assessed by direct invasive measurement; beat-by-beat stroke volume and cardiac output (index) were assessed by simultaneous pulse-wave doppler intracardiac echocardiography.
RESULTS
Simulated AF led to significant impairment of left ventricular systolic and diastolic function. Both loss of atrial contraction and heart rate irregularity significantly contributed to hemodynamic impairment. This effect was pronounced with increasing heart rate.
CONCLUSION
Our findings strengthen the rationale for therapeutic strategies aiming at rhythm control and heart rate regularization in patients with AF.
Topics: Humans; Atrial Fibrillation; Ventricular Function, Left; Catheter Ablation; Hemodynamics; Heart Rate; Cardiac Pacing, Artificial
PubMed: 36069129
DOI: 10.1111/jce.15669 -
Physiology & Behavior May 2024The pathophysiology of atrial fibrillation and ventricular tachycardia that result in cardiac arrhythmias is related to the sustained complicated mechanisms of the... (Review)
Review
The pathophysiology of atrial fibrillation and ventricular tachycardia that result in cardiac arrhythmias is related to the sustained complicated mechanisms of the autonomic nervous system. Atrial fibrillation is when the heart beats irregularly, and ventricular arrhythmias are rapid and inconsistent heart rhythms, which involves many factors including the autonomic nervous system. It's a complex topic that requires careful exploration. Cultivation of speculative knowledge on atrial fibrillation; the irregular rhythm of the heart and ventricular arrhythmias; rapid oscillating waves resulting from mistakenly inconsistent P waves, and the inclusion of an autonomic nervous system is an inconceivable approach toward clinical intricacies. Autonomic modulation, therefore, acquires new expansions and conceptions of appealing therapeutic intelligence to prevent cardiac arrhythmia. Notably, autonomic modulation uses the neural tissue's flexibility to cause remodeling and, hence, provide therapeutic effects. In addition, autonomic modulation techniques included stimulation of the vagus nerve and tragus, renal denervation, cardiac sympathetic denervation, and baroreceptor activation treatment. Strong preclinical evidence and early human studies support the annihilation of cardiac arrhythmias by sympathetic and parasympathetic systems to transmigrate the cardiac myocytes and myocardium as efficient determinants at the cellular and physiological levels. However, the goal of this study is to draw attention to these promising early pre-clinical and clinical arrhythmia treatment options that use autonomic modulation as a therapeutic modality to conquer the troublesome process of irregular heart movements. Additionally, we provide a summary of the numerous techniques for measuring autonomic tone such as heart rate oscillations and its association with cutaneous sympathetic nerve activity appear to be substitute indicators and predictors of the outcome of treatment.
Topics: Humans; Atrial Fibrillation; Heart; Autonomic Nervous System; Sympathetic Nervous System; Heart Rate
PubMed: 38527577
DOI: 10.1016/j.physbeh.2024.114527 -
Comparative Biochemistry and... Aug 2002Heart rate (HR) in avian embryos developing inside an eggshell has been measured by various means while maintaining adequate gas exchange through the eggshell. This is... (Review)
Review
Heart rate (HR) in avian embryos developing inside an eggshell has been measured by various means while maintaining adequate gas exchange through the eggshell. This is an important requirement in order to avoid adverse effects of impeding gas exchange on the cardiac rhythms of developing embryos. The present report is a review of our ontogenetic study on embryonic HR, which was measured with fulfillment of the above requirement and also hatchling HR measured non-invasively. Firstly, we reviewed measurements of daily changes (developmental patterns) in embryonic mean heart rate (MHR), which were determined from a short-term measurement of HR once a day, in 34 species of altricial and precocial birds. The allometric relationship between the MHR during pipping in altricial birds and their fresh egg masses was the same as that between the MHR at 80% of incubation duration and fresh egg masses in pre-cocial birds. Secondly, we presented the developmental patterns of MHR in chick embryos and hatchlings, which were determined from long-term, continuous measurement of HR before, during and after hatching. The ultradian and circadian rhythms of HR were clearly shown in embryos and hatchlings, respectively. Thirdly, we summarized instantaneous HR fluctuations: HR variability and HR irregularities, in chick embryos and hatchlings. The distinctive patterns were shown in pre-pipped and pipped embryos and newly hatched chicks, individually, which were partly related to autonomic nervous functions and physiological functions.
Topics: Analysis of Variance; Animals; Animals, Newborn; Birds; Chick Embryo; Heart; Heart Rate; Models, Cardiovascular; Periodicity
PubMed: 12095855
DOI: 10.1016/s1095-6433(02)00125-3