Percentage Of Adjacent RR Intervals Research Articles

The Relationship Between Sexual Activity and Heart Rate Variability in Menopausal Women.

Background:Menopause is an important life stage for women, which can bring along sexual and cardiac problems. Increased heart rate variability is an indicator of parasympathetic activity and is associated with mental and physical health and life expectancy. This study aimed to evaluate the effect of sexual activity (only penile–vaginal intercourse but not masturbation or non-coital sex with a partner) on heart rate variability in healthy menopausal women.Methods:We evaluated 130 menopausal patients aged 45-60 years, without chronic disease. The average weekly sexual activity numbers remembered in the last 1 year were questioned. The patients were divided into 2 groups according to the presence of sexual activity. The sexually active group was divided into subgroups as 1 per week and 2 or more per week. Menopause Rating Scale was applied for menopausal symptoms. Heart rate variability was analyzed from the 24-hour electrocardiography Holter recording.Results:Heart rate variability parameters were higher in the sexually active group than in the sexually inactive group (mean of the standard deviations of all the NN intervals for each 5 min segment of a 24-hour heart rate variability recording: P = .004; root mean square of differences between adjacent normal RR intervals, expressed in ms: P = .001; number of NN intervals exceeding 50 milliseconds: P = .011; percentage of adjacent RR intervals with a difference of duration >50 ms: P = .009; low frequency: P = .011; high frequency: P = .008, low frequency/high frequency: P = .018). When assessed by multiple linear regression analysis by adjusting for age, body mass index, and menopause duration, the variables mean of the standard deviations of all the NN intervals for each 5 min segment of a 24-hour heart rate variability recording, root mean square of differences between adjacent normal RR intervals, expressed in ms, and low frequency were independently associated with the number of sexual activities per week (B = 2.89 ± 1.02, 95% CI = 0.866-4.91, P = .005; B = 4.57 ± 1.83, 95% CI = 0.94-8.2, P = .014; and B = 1174.9 ± 592.2, 95% CI = 2.9-2346.9, P = .049, respectively).Conclusion:In healthy menopausal women, continued sexual activity with penile–vaginal intercourse is associated with better health outcomes on cardiac autonomic function through higher heart rate variability, an index of parasympathetic activity.

Are signs and symptoms in cardiovascular rehabilitation correlated with heart rate variability? An observational longitudinal study.

To analyze the correlation between the appearance of signs/symptoms during a cardiovascular rehabilitation program and linear indexes of the heart rate variability (HRV) at rest. To carry out the present observational longitudinal study, 48 patients were analyzed. The protocol was divided into two stages. First, the patients had their personal details collected, and the autonomic modulation at rest was evaluated by HRV. Second, they underwent 36 sessions of the cardiovascular rehabilitation program to evaluate signs/symptoms. Then, just for analysis of the data, they were divided into two groups: the group without signs/symptoms (n = 26; 65.15 ± 9.7 years); and the group with signs/symptoms (n = 22; 66.77 ± 14.4 years). The HRV indexes were compared by ancova. The effect size was measured through the partial eta-squared. Pearson's and Spearman's correlations (P < 0.05) were used to analyze the data, and linear regression was applied. A total of 103 signs/symptoms occurred. The group with signs/symptoms presented lower values of HRV indexes when compared with the group without signs/symptoms, especially for the parasympathetic indexes with a large effect size. The root mean square of successive differences (rMSSD), percentage of adjacent RR intervals with a difference of duration >50 ms (pNN50), high-frequency spectral component (HF) varying from 0.15 to 0.4 Hz (expressed as ms2 ), dispersion of the points perpendicular to the line of identity and represents the instantaneous record of the beat-to-beat variability (SD1) and SD1/scatter of points along the identity line and represents the HRV in long-term records (SD2) index presented a negative correlation with the appearance of signs/symptoms. When the linear regression was applied, the rMSSD, SD1 and SD1/SD2 showed negative values of β (P < 0.05). Patients with lower HRV are more likely to have signs/symptoms. The rMSSD, pNN50, HF (expressed as ms2 ), SD1 and SD1/SD2 index presented a negative correlation with the appearance of signs/symptoms. For rMSSD, SD1 and SD1/SD2, the lower the values of these HRV indexes, the greater the risk of appearance of signs/symptoms. Geriatr Gerontol Int 2020; 20: 853-859.

Effect of an Exergaming-Based Dance Training Paradigm on Autonomic Nervous System Modulation in Healthy Older Adults: A Randomized Controlled Trial.

The purpose of this study was to determine if an exergaming-based dance training protocol can improve heart rate variability (HRV) in healthy older adults. A total of 20 healthy older adults (≥65years old) were randomly assigned to two groups. The intervention group received an exergaming-based dance aerobic training for 6 weeks, while the control group received a 1-hr education on conventional physical exercises. Data obtained from HRV analysis pre- (Week 0) and postintervention (Week 7) consisted of high-frequency power, low- and high-frequency ratio, and root mean square of differences and percentage of adjacent RR intervals with a difference of duration greater than 50ms values. HRV was assessed during rest and during a 6-min walk test. In addition, the YMCA submaximal cycle ergometer test was used to acquire estimated maximal O2 consumption pre- and postintervention. After the training, the intervention group showed significant improvement in HRV high-frequency power, root mean square of differences, and percentage of adjacent RR intervals with a difference of duration greater than 50ms values in both rest and 6-min walk test conditions compared with the control group. Similarly, the intervention group showed higher maximal O2 consumption compared with the control group after the training. Our results support the effectiveness of an exergaming-based dance aerobic training on improving cardiac autonomic control in aging.

Interaction Between Cortical Auditory Processing and Vagal Regulation of Heart Rate in Language Tasks: A Randomized, Prospective, Observational, Analytical and Cross-Sectional Study

Cortical auditory evoked potentials (CAEP) throughout a language task is beneficial during psychophysiological evaluation to advance identification of language disorders. So as to better comprehend human communication and to provide additional elements for neuropsychological examinations we aimed to (1) examine the influence of language tasks on cortical auditory processing and vagal control of heart rate and (2) to verify a possible association between the parasympathetic cardiac regulation and cortical auditory processing in language tasks. This study was completed with 49 women. The subjects were separated into two groups: (1) phonological language tasks (N = 21) and (2) semantic (N = 21) language tasks. Heart rate variability (HRV) and CAEP were evaluated before and after the tests. HRV reduced (small effect size) and P3 wave latency increased after the phonological task. Identical variables were significantly correlated after the phonological task and linear regression indicated significant interaction between pNN50 (percentage of adjacent RR intervals with a difference of duration greater than 50 milliseconds) and P3 latency (16.9%). In conclusion, phonological language tasks slightly reduced parasympathetic control of HR and increased cognitive effort. The association between HRV and CAEP are anticipated to be involved in this mechanism.

Association between heart rhythm and cortical sound processing.

Sound signal processing signifies an important factor for human conscious communication and it may be assessed through cortical auditory evoked potentials (CAEP). Heart rate variability (HRV) provides information about heart rate autonomic regulation. We investigated the association between resting HRV and CAEP. We evaluated resting HRV in the time and frequency domain and the CAEP components. The subjects remained at rest for 10 minutes for HRV recording, then they performed the CAEP examinations through frequency and duration protocols in both ears. Linear regression indicated that the amplitude of the N2 wave of the CAEP in the left ear (not right ear) was significantly influenced by standard deviation of normal-to-normal RR-intervals (17.7%) and percentage of adjacent RR-intervals with a difference of duration greater than 50 milliseconds (25.3%) time domain HRV indices in the frequency protocol. In the duration protocol and in the left ear the latency of the P2 wave was significantly influenced by low (LF) (20.8%) and high frequency (HF) bands in normalized units (21%) and LF/HF ratio (22.4%) indices of HRV spectral analysis. The latency of the N2 wave was significantly influenced by LF (25.8%), HF (25.9%) and LF/HF (28.8%). In conclusion, we promote the supposition that resting heart rhythm is associated with thalamo-cortical, cortical-cortical and auditory cortex pathways involved with auditory processing in the right hemisphere.

Association of cardiac autonomic modulation with physical and clinical features of young people with type 1 diabetes.

The objective of this study was to verify possible associations between heart rate variability indices and physical activity, body composition, and metabolic and cardiovascular parameters in individuals with type 1 diabetes. A total of 39 young patients with type 1 diabetes were included. Body composition, physical activity, cardiovascular parameters, and metabolic parameters were assessed. For the heart rate variability analysis, heart rate was recorded beat-by-beat using a Polar S810i heart rate monitor for 30 minutes, with the volunteers in the supine position; subsequently, the following indices were considered: standard deviation of all normal RR intervals; root-mean square of differences between adjacent normal RR intervals in a time interval; percentage of adjacent RR intervals with a difference of duration >50 ms; high frequency component in milliseconds squared; high frequency component in normalised units; standard deviation of the instantaneous variability beat-to-beat; and standard deviation of the long-term variability. The association between the heart rate variability indices and independent variables was verified through linear regression in unadjusted and adjusted models (considering gender and age). The statistical significance was set at 5% and the confidence interval at 95%. High values of at-rest heart rate were associated with reduced parasympathetic activity and global heart rate variability, and higher values of waist-to-hip ratio were related to lower parasympathetic activity, independent of age or gender. For young patients with type 1 diabetes, increases in at-rest heart rate values are associated with reduced parasympathetic activity and global heart rate variability, whereas higher waist-to-hip ratio values are related to lower parasympathetic activity, both independent of age and gender.

Correlation between indexes of autonomic maneuvers and heart rate variability in hemodialysis patients.

The autonomic maneuvers are simple methods to evaluate autonomic balance, but the association between autonomic maneuvers and heart rate variability (HRV) in hemodialysis patients remains unknown. This study aimed to evaluate the correlation between HRV and respiratory sinus arrhythmia (RSA) and Valsalva maneuver (VM) indexes in hemodialysis patients and to compare two methods for RSA indexes acquisitions. Forty-eight volunteers on hemodialysis (66.7% men) were evaluated by VM, RSA, and 24h Holter monitoring. At the VM, the Valsalva index (VI) was the variable considered. In the RSA, the ratio and difference between the RR intervals of inspiratory and expiratory phase (E:I and E-I, respectively) were considered by traditional form (average of respiratory cycles) and independent respiratory cycles (E:Iindep and E-Iindep). The HRV indexes evaluated were standard deviation of all normal RR intervals (SDNN), standard deviation of sequential 5-min RR interval means (SDANN), root mean square of the successive differences (rMSSD) and percentage of adjacent RR intervals with difference of duration greater than 50ms (pNN50). The SDNN, SDANN showed significant correlation with all classic indexes of RSA (E:I: r=0.62, 0.55, respectively, E-I: r=0.64, 0.57, respectively), E:Iindep (r=0.59, 0.54, respectively), E-Iindep (r=0.47, 0.43, respectively) and VI (r=0.42, 0.34, respectively). Significant correlation of rMSSD with E:I (r=0.37), E-I (r=0.41) and E:Iindep (r=0.34) was also observed. There was no association of any variable with pNN50. Have been show high values for all variables of independent cycles method (p<0.05). The autonomic maneuvers, especially RSA, are useful methods to evaluate cardiac autonomic function in hemodialysis patients. The acquisition of the RSA index by independent cycles should not be used in this population.

Heart rate variability in practitioners of hippotherapy with down syndrome

Background: Down syndrome (DS) can lead to motor, cognitive, and socio-affective disorders, and hippotherapy is one therapeutic modality. Alterations in heart rate (HR), defined as heart rate variability (HRV), are modulate by autonomous nervous system. However, many descriptions in the research literature on HRV in practitioners of hippotherapy with DS were not found. The hypothesis of this study is that hippotherapy can generate an increase in HRV in practitioners with DS due to the stimuli offered by the activity and movement of the horse. Purpose: To evaluate heart rate variability in practitioners of hippotherapy with DS before, during and after their practice. Methods: For this study, 6 children with Down syndrome, mean age 12± 1.6 years were recruited. The HR was obtained and calculated by the uptake of RR intervals (R-Ri) of the electrocardiogram, with a cardiofrequencimetre (Polar® RS800CX Heart Rate Monitor – Kempele – Finland), for 5 sessions of hippotherapy for 30 minutes once weekly. HR was collected before, during and after each session. For all statistical analysis, Sigma-Stat® Software version 3.5 was used and a significance level of p value lower than 5% (p< 0.05) were considered. Results: In the data analysis but with no significant results tended to decrease parasympathetic activity at rest, observed by rMSSD indices (square root of the mean squared differences between successive normal intervals) and pNN50 (percentage of adjacent RR intervals differing by duration 50 ms) between the first and fifth sessions. In the frequency domain values of HF (high frequency) have not changed. With respect to sympathetic activity observed at LF index (low frequency), we noted increasing trend. Was also found a significant decrease in parasympathetic activity (p= 0.031), observed by pNN50 index when comparing the behavior of the HR during the first and fifth sessions of hippotherapy in rMSSD index showed a tendency to decrease. In the frequency domain, there were no significant difference in the analyzed components, however, tended to increase in LF and decrease in HF comparing the period during sessions of hippotherapy. Conclusion(s): Through the proposed study it was concluded that during hippotherapy sessions pure threedimensional motion as well as the environment of a hippotherapy centre did not improve HRV in children with DS, so not confirming the hypothesis. Implications: This study showed that the threedimensional movement of the horse alone did not increase heart rate variability in children with DS. Further studies with a larger sample size and longer time should be performed in order to confirm whether HRV can be improved or not by hippotherapy.

Effects of auditory stimulation with music of different intensities on heart period

Various studies have indicated that music therapy with relaxant music improves cardiac function of patients treated with cardiotoxic medication and heavy-metal music acutely reduces heart rate variability (HRV). There is also evidence that white noise auditory stimulation above 50 dB causes cardiac autonomic responses. In this study, we aimed to evaluate the acute effects of musical auditory stimulation with different intensities on cardiac autonomic regulation. This study was performed on 24 healthy women between 18 and 25 years of age. We analyzed HRV in the time [standard deviation of normal-to-normal RR intervals (SDNN), percentage of adjacent RR intervals with a difference of duration >50 ms (pNN50), and root-mean square of differences between adjacent normal RR intervals in a time interval (RMSSD)] and frequency [low frequency (LF), high frequency (HF), and LF/HF ratio] domains. HRV was recorded at rest for 10 minutes. Subsequently, the volunteers were exposed to baroque or heavy-metal music for 5 minutes through an earphone. The volunteers were exposed to three equivalent sound levels (60–70, 70–80, and 80–90 dB). After the first baroque or heavy-metal music, they remained at rest for 5 minutes and then they were exposed to the other music. The sequence of songs was randomized for each individual. Heavy-metal musical auditory stimulation at 80–90 dB reduced the SDNN index compared with control (44.39 ± 14.40 ms vs. 34.88 ± 8.69 ms), and stimulation at 60–70 dB decreased the LF (ms2) index compared with control (668.83 ± 648.74 ms2 vs. 392.5 ± 179.94 ms2). Baroque music at 60–70dB reduced the LF (ms2) index (587.75 ± 318.44 ms2 vs. 376.21 ± 178.85 ms2). In conclusion, heavy-metal and baroque musical auditory stimulation at lower intensities acutely reduced global modulation of the heart and only heavy-metal music reduced HRV at higher intensities.

Heart rate variability during hemodialysis in patients with chronic renal disease

Background: Few studies evaluated cardiac autonomic responses induced by hemodialysis. We aimed to evaluate cardiac autonomic regulation during hemodialysis in haemodynamically stable patients with chronic renal disease. Method: Heart rate variability (HRV) was analyzed in the time and frequency domains in the following periods: Pre-dialysis (10 minutes before); Hemodialysis (240 minutes). Results: The standard deviation of all normal RR intervals (SDNN) increased 60-90min after hemodialysis compared to pre-hemodialysis (29.77 ± 12ms vs. 51.70 ± 41.6ms - p<0.05). The percentage of adjacent RR intervals with a difference of duration greater than 50ms (pNN50) also raised 180-210 min after hemodialysis compared to 0-30 min after hemodialysis (1.29 ± 3.5 vs. 4.37 ± 7.8 - p<0.05). Low frequency (LF) (ms2) increased 150-180 min after hemodialysis compared to pre-hemodialysis (168.2±179.8 ms2 vs. 562.6±455.7 ms2: p<0.05) and high frequency (HF) (ms2) band raised 150-180min and 180-210 after hemodialysis compared to pre-hemodialysis (59.3 ± 70.78ms2 vs. 212.5 ± 304.9 ms2 vs. 186.3 ± 335.1 ms2: p<0.05). Conclusion: Hemodialysis acutely increased HRV, raising the parasympathetic component of HRV.

Cardiovagal Response to Acute Mild Exercise in Young Healthy Subjects

The aim of the present study was to investigate the effect of a single bout of mild exercise on autonomic nervous system activity in healthy subjects. The study group comprised 18 healthy males, aged between 20 and 24 years, who had not been training regularly for the last 3 months. A supine recording of systolic arterial pressure (SAP) and RR interval and the administration of the phenylephrine test were performed at baseline and repeated after a 60-min recovery period following treadmill exercise training for 30 min at 65% of maximal heart rate. Mean SAP and RR interval, heart rate variability (HRV) indices (the standard deviation of normal-to-normal RR intervals (SDNN), the square root of the mean of squared differences between successive intervals and the percentage of adjacent RR intervals differing more than 50 ms), noninvasive spectral baroreflex sensitivity (Spe-BRS) and phenylephrine baroreflex sensitivity (Phe-BRS) were assessed before and after training. Mean SAP measured after exercise was lower than baseline (120+/-12 mmHg vs 128+/-12 mmHg, p = 0.05). Spe-BRS and Phe-BRS increased significantly after exercise, from 11.8+/-6.1 ms/mmHg to 16.0+/-7.8 ms/mmHg (p = 0.034), and from 16.0+/-8.8 ms/mmHg to 21.9+/-9.3 ms/mmHg (p = 0.022), respectively. A parallel increase was also observed in SDNN (from 81+/-44 ms to 96+/-53 ms, p = 0.02), but the other HRV indices showed no significant differences between pre- and post-exercise. A single session of mild exercise performed by sedentary young men leads to significant autonomic nervous system improvement, which suggests that even mild physical activity is beneficial for neural cardiac regulation and should be recommended to sedentary healthy subjects.

Predictive value of heart rate variability for the recurrence of chronic atrial fibrillation after electrical cardioversion.

The relation between heart rate variability (HRV) and occurrence of atrial fibrillation (AF) in paroxysmal AF has been well studied, but there are controversial observations regarding the relation of HRV parameters to the recurrence of chronic AF after cardioversion. The present study compared HRV parameters of patients with chronic AF on the second day of cardioversion with a healthy control group and investigated their predictive value for AF recurrence. Forty-one patients with chronic AF (> 3 months), who had various underlying cardiovascular disorders, were enrolled to the study. Of these, 31 patients were successfully cardioverted by external direct current shock, but 27 patients fulfilled the entry criteria. Twenty healthy subjects served as a control group. On the second day of restoration of sinus rhythm, 24-h Holter recording was obtained and the following time-domain indices of HRV were measured: SDNN (the standard deviation of the mean RR interval expressed in ms), SDANN (the SD of the averages of RR intervals in all 5-min segments of the 24-h recording), rMSSD (the root mean square of differences of successive RR intervals), and pNN50 (the percentage of adjacent RR intervals that differed by more than 50 ms). Patients were followed-up for 6 weeks for recurrence of AF. After cardioversion, SDNN and SDANN were found to be significantly lower in the AF group than in the control group (86.4 +/- 31.7 ms vs. 142.1 +/- 40.2 ms, and 57 +/- 17.4 ms vs. 124.4 +/- 37.7 ms, p < 0.001 and p < 0.001, respectively). The indices of vagal modulation of heart rate (rMSS and pNN50) were not different between the AF group and the control group. Recurrence of AF was observed in 15 patients. In these patients, all HRV parameters were significantly depressed compared with those with maintained sinus rhythm. Logistic regression analysis revealed that only decreased pNN50 was an independent predictor of AF relapse (relative risk = 1.5, p = 0.02, 95% confidence interval 1.1-2.2). There was also a trend toward a shortened SDNN as a predictor of AF recurrences. Suppressed HRV parameters and decreased vagal tone are probably a risk factor for AF recurrences after cardioversion to sinus rhythm in a specific subset of patients with chronic AF.