Wpływ częstotliwości oddychania spoczynowego na parametry tachografów zmienności rytmu serca

The relaxation response is a method of overcoming stress factors. It is activated through slow breathing, which causes high heart rate variability. Higher heart rate variability increases the activity of parasympathetic nervous system causing organism to relax. The relaxation response is activated, when human organism achieves a state of inner balance, which is called the coherence. One of techniques to achieve this state of balance is breathing in the specific rhythm, which is usually around 0.1 Hz of frequency. This value is called the resonance frequency. In this study the activity of central nervous system in the specific range of breathing frequencies (0.07-0.12 Hz) has been checked in order to find an answer, if the relaxation response is triggered by one specific frequency or is there a specific range of breathing frequencies, which lead to the state of inner balance. In order to check the changes throughout human body the heart rate assessed by biofeedback technique has been used. It is a non-invasive method examining the function of sympathetic and parasympathetic nervous system through the changes in natural heart rhythm. Throughout the biofeedback sessions the resonance frequency is measured. The aim of this study was to check if there is a difficulty for subjects to maintain imposed breathing rhythm and if there is only one universal resonance frequency for everyone or is there a specified range. The study confirmed the difficulty of maintaining unnatural breathing frequency. It has also showed that there is a specific range of frequency values which can be used to achieve the coherence state.Odpowiedź relaksacyjna, to sposób walki ze stresem; wiąże się ze spokojniejszym oddychaniem, które powoduje wysoką zmienność rytmu serca, w efekcie czego wzrasta aktywność parasympatycznego układu nerwowego PUN, powodując wyciszenie organizmu. Odpowiedź ta jest wyzwalana w momencie wprowadzenia organizmu w stan wewnętrznej równowagi, określany mianem koherencji. Jedną z technik osiągnięcia stanu równowagi jest oddychanie zgodne z rytmem częstotliwości rezonansowej, która przeciętnie wynosi 0.1 Hz. W tych badaniach sprawdzono zachowanie ośrodkowego układu nerwowego OUN w przedziale częstotliwości 0,07-0,12 Hz celem sprawdzenia, czy odpowiedź relaksacyjna RR dotyczy tylko jednej specyficznej częstotliwości, czy też istnieje tolerancja częstotliwości oddychania wywołująca tożsame odpowiedzi organizmu. Aby zbadać zmiany zachodzące w organizmie, posłużono się tzw. metodą biofeedback HRV. Jest to metoda nieinwazyjna, badająca poprzez zmiany rytmu serca działanie sympatycznego układu nerwowego SUN i PUN. Na takich sesjach mierzy się częstotliwość rezonansową, aby instruować uczestników – jak kierować oddechem w celu utrzymania pożądanego tempa oddychania. Analizowano sensowność utrzymywania konkretnego rytmu. Badano również, czy istnieje trudność w dostosowaniu własnego oddechu do wymaganego tempa. Badania potwierdziły problem wynikający z utrzymania sugerowanego rytmu oddychania. Wykazano również, że istnieje zakres rytmu wentylacji pozwalający uzyskać efekty podobne, jak podczas oddychania w tempie rezonansowym

A Feature Selection Method for Driver Stress Detection Using Heart Rate Variability and Breathing Rate

Driver stress is a major cause of car accidents and death worldwide. Furthermore, persistent stress is a health problem, contributing to hypertension and other diseases of the cardiovascular system. Stress has a measurable impact on heart and breathing rates and stress levels can be inferred from such measurements. Galvanic skin response is a common test to measure the perspiration caused by both physiological and psychological stress, as well as extreme emotions. In this paper, galvanic skin response is used to estimate the ground truth stress levels. A feature selection technique based on the minimal redundancy-maximal relevance method is then applied to multiple heart rate variability and breathing rate metrics to identify a novel and optimal combination for use in detecting stress. The support vector machine algorithm with a radial basis function kernel was used along with these features to reliably predict stress. The proposed method has achieved a high level of accuracy on the target dataset.Comment: In Proceedings of the 15th International Conference on Machine Vision (ICMV), Rome, Italy, 18-20 November 2022. arXiv admin note: text overlap with arXiv:2206.0322

THE EFFECT OF SALIVARY TESTOSTERONE LEVELS ON HEART RATE VARIBILITY ON STUDENTS OF MEDICAL FACULTY OF JENDRAL SOEDIRMAN UNIVERSITY

Testosterone is a steroid hormone produced by Leydig cells in testis. Testosterone levels can be measured through a saliva sampel. Testosterone have effect in the cardiovascular system. Testosterone can affect cardiac contractility and has a cardioprotective role in maintaining the autonomic balance of the heart. Cardiac autonomic activity can be assessed by Heart Rate Varibility (HRV). This study aims to determine the effect of salivary testosterone levels on HRV in FK Unsoed students. This study was an analytic observational study with a cross sectional approach. The number of subjects in this study were 31 students who were taken by consecutive sampling, with inclusion criteria, namely male gender, age 17-25 years, agreed to the informed consent, BMI 18,5-24,9 kg/m2, body temperature 36,5-37,5 ℃, and low to moderate level of physical activity. Testosterone levels were measured using the Salimetrics ELISA method. HRV were measured using a POLAR M400 heart rate monitor and the Welltory application with the result of HRV parameters in the form of SDNN. The data normality test used the Saphiro-Wilk test. Bivariate analysis used Pearson’s correlative parametric test. The subjects of the study had a low mean testosterone saliva levels, namely 12,38±3,70 pg/mL and a low mean SDNN of 56,74±19,70 ms. The results of the Pearson correlation test of testosterone with SDNN shows the value of r = 0,147 and the value of p = 0,429, so it can be concluded that there is no correlation between testosterone saliva levels and HRV in SDNN parameters

Alterations in autonomic cardiac modulation in response to normobaric hypoxia

Purpose: The present study aimed to determine if autonomic cardiac modulation was influenced by acute exposure to normobaric hypoxia. Method: Ten healthy male lowland dwellers completed five block-randomised single-blinded, crossed-over acute exposures to a normobaric hypoxic environment, each separated by 24 hours’ recovery (20.3%, 17.4%, 14.5%, 12.0% and 9.8% FIO2). Supine recordings were made of arterial oxygen saturation and electrocardiogram (ECG). RR intervals from the ECG trace were analysed for time (SDNN, lnRMSSD), frequency (lnVLF, lnLF, lnHF, lnTP, LFnu, and HFnu), and nonlinear (DFA-α1 and SampEn) heart rate variability components. Results: A significant reduction in arterial SaO2 occurred with reduced FIO2, along with a rise in heart rate (Cohen’s d = 1.16, 95% Confidence Interval [2.64–6.46]), significant at 9.8% FIO2. A decrease in autonomic cardiac modulation was also found as shown by a statistically significant (at 9.8% FIO2) decrease in lnTP (d = 1.84 [1.74–1.94]), and SampEn (d = 0.98 [0.83–1.12]) and an increase in DFA-α1 (d = 0.72 [0.60–0.84]) from normoxia at 9.8% FIO2. Conclusion: The decrease in variability indicated a reduction in autonomic cardiac modulation. There appears to be a threshold ∼9.8% FIO2 (∼6000 m equiv.), below which significant alterations in autonomic control occur

Pengaruh Fase Folikuler dan Fase Luteal terhadap Heart Rate Variability Mahasiswi Fakultas Kedokteran Universitas Jenderal Soedirman

Latar belakang: Fase folikuler merupakan proses pertummbuhan folikel di dalam ovarium hingga terjadinya ovulasi. Sedangkan fase luteal adalah proses setelah ovulasi hingga fase premenstruasi. Kedua fase tersebut dapat mempengaruhi sistem kardiovaskuler melalui aktivitas hormon estrogen dan progesteron. Aktivitas otonom jantung dapat dinilai dengan Heart Rate Variability (HRV). Tujuan: Penelitian ini bertujuan untuk mengetahui pengaruh fase folikuler dan fase luteal terhadap heart variability mahasiswi Fakultas Kedokteran Universitas Jenderal Soedirman. Metode: Jumlah subjek dalam penelitian ini sebanyak 32 mahasiswi yang diambil dengan metode consecutive sampling sesuai dengan kriteria inklusi yaitu wanita berusia 17-25 tahun, menyetujui informed consent, siklus menstruasi teratur dilihat dari 6 bulan sebelumnya, IMT 18-24,9, dan tingkat aktivitas fisik rendah sampai sedang. Pengukuran fase folikuler dan fase luteal menggunakan metode kalender. Pengukuran HRV menggunakan alat MEDICORE SA-3000P dengan hasil parameter HRV berupa SDNN. Uji normalitas data menggunakan uji Shaphiro-Wilk. Analisis bivariat menggunakan uji non parametrik Uji Wilcoxon. Hasil: Hasil penelitian menunjukkan bahwa subjek penelitian memilki rerata SDNN rendah pada fase folikuler sebesar 54,9 ± 25 ms dan pada fase luteal sebesar 45,8 ± 17,7 ms. Hasil uji Wilcoxon fase folikuler dan fase luteal dengan SDNN menunjukkan nilai p=0,011 sehingga didapatkan perbedaan signifikan antara fase folikuler dan fase luteal dengan HRV pada parameter SDNN. Kesimpulan: Hasil penelitian menunjukkan adanya pengaruh bahwa pada fase folikuler memiliki nilai HRV yang lebih tinggi daripada fase luteal

Past strong experiences determine acute cardiovascular autonomic responses to acoustic stress

Background: Stress is a major risk factor for cardiovascular (CV) disease. We hypothesized that past strong experiences might modulate acute CV autonomic responses to an unexpected acoustic stimulus. A i m: The study’s aim was to compare acute CV autonomic responses to acoustic stress between students with and without a past strong experience associated with the acoustic stimulus. Materials and Methods: Twenty five healthy young volunteers - medical and non-medical students - were included in the study. CV hemodynamic parameters, heart rate (HR), and blood pressure (BP) variability were assessed for 10 min at rest and for 10 min after two different acoustic stimuli: a standard sound signal and a specific sound signal used during a practical anatomy exam (so-called "pins"). Results: Both sounds stimulated the autonomic nervous system. The "pins" signal caused a stronger increase in HR in medical students (69 ± 10 vs. 73 ± 13 bpm, p = 0.004) when compared to non-medical students (69 ± 6 vs. 70 ± 10, p = 0.695). Rises in diastolic BP, observed 15 seconds after sound stressors, were more pronounced after the "pins" sound than after the standard sound signal only in medical students (3.1% and 1.4% vs. 3% and 4.4%), which was also reflected by low-frequency diastolic BP variability (medical students: 6.2 ± 1.6 vs. 4.1 ± 0.8 ms2, p = 0.04; non-medical students: 6.0 ± 4.3 vs. 4.1 ± 2.6 ms2, p = 0.06). Conclusions: The "pins" sound, which medical students remembered from their anatomy practical exam, provoked greater sympathetic activity in the medical student group than in their non-medical peers. Thus, past strong experiences modulate CV autonomic responses to acute acoustic stress

Recovery of heart rate variability after treadmill exercise analyzed by lagged Poincaré plot and spectral characteristics

© 2017 International Federation for Medical and Biological Engineering The aim of this study was to analyze the recovery of heart rate variability (HRV) after treadmill exercise and to investigate the autonomic nervous system response after exercise. Frequency domain indices, i.e., LF(ms 2 ), HF(ms 2 ), LF(n.u.), HF(n.u.) and LF/HF, and lagged Poincaré plot width (SD1 m ) and length (SD2 m ) were introduced for comparison between the baseline period (Pre-E) before treadmill running and two periods after treadmill running (Post-E1 and Post-E2). The correlations between lagged Poincaré plot indices and frequency domain indices were applied to reveal the long-range correlation between linear and nonlinear indices during the recovery of HRV. The results suggested entirely attenuated autonomic nervous activity to the heart following the treadmill exercise. After the treadmill running, the sympathetic nerves achieved dominance and the parasympathetic activity was suppressed, which lasted for more than 4 min. The correlation coefficients between lagged Poincaré plot indices and spectral power indices could separate not only Pre-E and two sessions after the treadmill running, but also the two sessions in recovery periods, i.e., Post-E1 and Post-E2. Lagged Poincaré plot as an innovative nonlinear method showed a better performance over linear frequency domain analysis and conventional nonlinear Poincaré plot