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Kujawski S, Buszko K, Cudnoch-Jędrzejewska A, Słomko J, Jakovljevic DG, Newton JL, Zalewski P. The impact of total sleep deprivation upon supine and head up tilt hemodynamics using non-linear analysis in firefighters. Biomed Signal Process Control 2021. [DOI: 10.1016/j.bspc.2021.102989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Garcia-Araújo AS, Pires Di Lorenzo VA, Labadessa IG, Jürgensen SP, Di Thommazo-Luporini L, Garbim CL, Borghi-Silva A. Increased sympathetic modulation and decreased response of the heart rate variability in controlled asthma. J Asthma 2014; 52:246-53. [PMID: 25158110 DOI: 10.3109/02770903.2014.957765] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To compare the autonomic modulation of heart rate (HR) in asthmatic and healthy volunteers to correlate it with the forced expiratory volume in the first second (FEV1). METHODS Ten healthy and 14 asthmatic volunteers were included in this cross-sectional study. The volunteers underwent a cardiopulmonary exercise test, spirometry and a register of both resting heart rate variability (HRV) in the supine and seated positions along with HRV during the respiratory sinus arrhythmia maneuver (M-RSA). RESULTS At rest in supine, asthmatic volunteers presented a higher HR (77.1 ± 9.9 vs. 68.7 ± 8.7 bpm), shorter interval between two R waves (R-Ri) (807.5 ± 107.2 vs. 887.5 ± 112.7 ms) when compared with the healthy volunteers, respectively. Moreover, in the frequency domain of HRV, there was increased low frequency (LF) index (50.4 ± 17.1 vs. 29.2 ± 11.1 n.u.) and decreased high frequency (HF) index (49.4 ± 17.1 vs. 70.7 ± 11.1 n.u.). During the M-RSA, the asthmatic presented higher HR (82.6 ± 10.0 vs. 72.4 ± 7.6 bpm) and lower values of R-Ri (746.4 ± 92.1 vs. 846.4 ± 81.4 ms) and approximate entropy (ApEn) (0.7 ± 0.0 vs. 0.8 ± 0.1). FEV1 was strongly correlated with the change of the continuous beat-to-beat variability of HR (SD2) index from the seated to the supine position (r = 0.78). CONCLUSION Controlled asthma in adults appears to induce an increased sympathetic modulation and attenuated response to the postural changes and the M-RSA. Furthermore, there is a correlation between the airways' obstruction and HRV, especially during postural changes.
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Kalash L, Sultan R. Routes to fractality and entropy in Liesegang systems. CHAOS (WOODBURY, N.Y.) 2014; 24:023121. [PMID: 24985435 DOI: 10.1063/1.4881077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Liesegang bands are formed when solutions of co-precipitate ions interdiffuse in a 1D gel matrix. In a recent study [R. F. Sultan, Acta. Mech. Sin. 27, 119 (2011)], Liesegang patterns have been characterized as fractal structures. In addition to experimentally obtained patterns, geometric Liesegang patterns were constructed in conformity with the well-known empirical laws. Both mathematical fractal dimensions and box count dimensions for images of PbF2 and PbI2 Liesegang patterns have been calculated. Liesegang patterns can also be described by the entropy state function, and categorized as more or less ordered structures. We revisit the relation between entropy and fractal dimension, and apply it to simulated geometrical Liesegang patterns. We have resort to three different routes for the estimation of the entropy of a Liesegang pattern. The HarFA software enabled the calculation of the Hausdorff dimension and the topological entropy, then the information dimension and the Shannon entropy. In a third pathway, analytical calculations were carried out by estimating the probability of occurrence of a fractal element or coverage. The product of Shannon entropy and Boltzmann constant yields the thermodynamic entropy. The values for PbF2 and PbI2 Liesegang patterns attained the order of magnitude of the reported Third Law entropies, but yet remained lower, in conformity with the more ordered Liesegang structures.
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Affiliation(s)
- Leen Kalash
- Department of Chemistry, American University of Beirut, Riad El Solh, 1107 2020 Beirut, Lebanon
| | - Rabih Sultan
- Department of Chemistry, American University of Beirut, Riad El Solh, 1107 2020 Beirut, Lebanon
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Siepmann M, Hennig UD, Siepmann T, Nitzsche K, Mück-Weymann M, Petrowski K, Weidner K. The Effects of Heart Rate Variability Biofeedback in Patients with Preterm Labour. Appl Psychophysiol Biofeedback 2013; 39:27-35. [DOI: 10.1007/s10484-013-9238-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Manor B, Lipsitz LA. Physiologic complexity and aging: implications for physical function and rehabilitation. Prog Neuropsychopharmacol Biol Psychiatry 2013; 45:287-93. [PMID: 22985940 PMCID: PMC3568237 DOI: 10.1016/j.pnpbp.2012.08.020] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 08/08/2012] [Accepted: 08/19/2012] [Indexed: 11/28/2022]
Abstract
The dynamics of most healthy physiological processes are complex, in that they are comprised of fluctuations with information-rich structure correlated over multiple temporospatial scales. Lipsitz and Goldberger (1992) first proposed that the aging process may be characterized by a progressive loss of physiologic complexity. We contend that this loss of complexity results in functional decline of the organism by diminishing the range of available, adaptive responses to the innumerable stressors of everyday life. From this relationship, it follows that rehabilitative interventions may be optimized by targeting the complex dynamics of human physiology, and by quantifying their effects using tools derived from complex systems theory. Here, we first discuss several caveats that one must consider when examining the functional and rehabilitative implications of physiologic complexity. We then review available evidence regarding the relationship between physiologic complexity and system functionality, as well as the potential for interventions to restore the complex dynamics that characterize healthy physiological function.
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Affiliation(s)
- Brad Manor
- Division of Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.
| | - Lewis A Lipsitz
- Division of Gerontology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA,Harvard Medical School, Boston, MA, USA,Center for Dynamical Biomarkers and Translational Medicine, National Central University, Taiwan,Institute for Aging Research, Hebrew SeniorLife, Roslindale, MA, USA
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Characterization of common measures of heart period variability in healthy human subjects: implications for patient monitoring. J Clin Monit Comput 2009; 24:61-70. [DOI: 10.1007/s10877-009-9210-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Accepted: 11/02/2009] [Indexed: 01/26/2023]
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Schoenenberger AW, Erne P, Ammann S, Perrig M, Bürgi U, Stuck AE. Prediction of hypertensive crisis based on average, variability and approximate entropy of 24-h ambulatory blood pressure monitoring. J Hum Hypertens 2007; 22:32-7. [PMID: 17625588 DOI: 10.1038/sj.jhh.1002263] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Approximate entropy (ApEn) of blood pressure (BP) can be easily measured based on software analysing 24-h ambulatory BP monitoring (ABPM), but the clinical value of this measure is unknown. In a prospective study we investigated whether ApEn of BP predicts, in addition to average and variability of BP, the risk of hypertensive crisis. In 57 patients with known hypertension we measured ApEn, average and variability of systolic and diastolic BP based on 24-h ABPM. Eight of these fifty-seven patients developed hypertensive crisis during follow-up (mean follow-up duration 726 days). In bivariate regression analysis, ApEn of systolic BP (P<0.01), average of systolic BP (P=0.02) and average of diastolic BP (P=0.03) were significant predictors of hypertensive crisis. The incidence rate ratio of hypertensive crisis was 14.0 (95% confidence interval (CI) 1.8, 631.5; P<0.01) for high ApEn of systolic BP as compared to low values. In multivariable regression analysis, ApEn of systolic (P=0.01) and average of diastolic BP (P<0.01) were independent predictors of hypertensive crisis. A combination of these two measures had a positive predictive value of 75%, and a negative predictive value of 91%, respectively. ApEn, combined with other measures of 24-h ABPM, is a potentially powerful predictor of hypertensive crisis. If confirmed in independent samples, these findings have major clinical implications since measures predicting the risk of hypertensive crisis define patients requiring intensive follow-up and intensified therapy.
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Affiliation(s)
- A W Schoenenberger
- University Department of Geriatrics, Spital Netz Bern Ziegler and University of Bern, Bern, Switzerland.
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Batchinsky AI, Cooke WH, Kuusela T, Cancio LC. Loss of complexity characterizes the heart rate response to experimental hemorrhagic shock in swine. Crit Care Med 2007; 35:519-25. [PMID: 17205017 DOI: 10.1097/01.ccm.0000254065.44990.77] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To improve our ability to identify physiologic deterioration caused by critical illness, we applied nonlinear and frequency-domain analytical methods to R-to-R interval (RRI) and systolic arterial pressure (SAP) time series during hemorrhagic shock. DESIGN Prospective, randomized, controlled trial. SETTING Animal laboratory of a government research institute. SUBJECTS Twenty swine (weight 36.4+/-0.11 kg). INTERVENTIONS Fixed-volume hemorrhage followed by resuscitation; off-line analysis of RRI and SAP data. MEASUREMENTS AND MAIN RESULTS Anesthetized swine (shock group, n=12) underwent withdrawal of 30 mL/kg blood in 10 mL/kg decrements. A control group (n=8) received maintenance fluids only. Electrocardiogram and arterial pressure waveforms were acquired at 500 Hz. Eight hundred-beat data sets were analyzed at six time points: at baseline, after each blood withdrawal, after lactated Ringer's resuscitation, and after infusion of shed blood. Nonlinear methods were used to estimate the complexity (approximate entropy, sample entropy, Lempel-Ziv entropy, normalized entropy of symbol dynamics), RRI bits per word, and fractal dimension by curve lengths and by dispersion analysis of the RRI and SAP time series. Fast Fourier transformation was used to measure the high-frequency and low-frequency powers of RRI and SAP. Baroreflex sensitivity was assessed in the time domain with the sequence method. Hemorrhagic shock caused decreases in RRI complexity as quantified by approximate entropy, sample entropy, and symbol dynamics; these changes were reversed by resuscitation. Similar but statistically insignificant changes in fractal dimension by curve lengths were seen. RRI high-frequency power decreased with hemorrhagic shock-indicating withdrawal of vagal cardiac input-and was restored by resuscitation. Similar changes in baroreflex sensitivity were seen. Hemorrhagic shock did not affect SAP complexity. CONCLUSIONS Hemorrhagic shock caused a reversible decrease in RRI complexity; these changes may be mediated by changes in vagal cardiac control. Assessment of RRI complexity may permit identification of casualties with hemorrhagic shock.
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Lewis MJ, Short AL, Lewis KE. Autonomic nervous system control of the cardiovascular and respiratory systems in asthma. Respir Med 2006; 100:1688-705. [PMID: 16524708 DOI: 10.1016/j.rmed.2006.01.019] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Revised: 01/19/2006] [Accepted: 01/25/2006] [Indexed: 12/01/2022]
Abstract
Patients with asthma have exaggerated bronchoconstriction of their airways in response to certain indirect (e.g. cold air, allergens, dust, exercise) or direct (e.g. inhaled methacholine) stimuli. This 'hyper-reactivity' usually co-exists with airway inflammation, although the pathophysiological mechanisms underlying these changes are not fully understood. It is likely that this hyper-reactivity is associated with abnormal autonomic nervous system (ANS) control. In particular, the parasympathetic (vagal) component of the ANS appears to be implicated in the pathogenesis of asthma. In addition, several studies have suggested the existence of differential alteration in ANS function following exercise in asthmatics compared with non-asthmatic individuals. Several early studies suggested that the altered autonomic control of airway calibre in asthma might be reflected by a parallel change in heart rate. Cardiac vagal reactivity does indeed appear to be increased in asthma, as demonstrated by the cardiac response to various autonomic functions tests. However, other studies have reported a lack of association between bronchial and cardiac vagal tone, and this is in accord with the concept of system-independent ANS control. This review provides a discussion of cardiovascular-autonomic changes associated with either the pathophysiology of asthma per se or with asthma pharmacotherapy treatment. Previous investigations are summarised suggesting an apparent association between altered autonomic-cardiovascular control and bronchial asthma. The full extent of autonomic dysfunction, and its clinical implications, has yet to be fully determined and should be the subject of future investigation.
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Affiliation(s)
- M J Lewis
- Department of Sports Science, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, UK.
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Min KA, Zhu X, Oh JM, Shin WG. Effect of oxolamine on anticoagulant effect of warfarin. Am J Health Syst Pharm 2006; 63:153-6. [PMID: 16390929 DOI: 10.2146/ajhp050255] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Kyoung A Min
- Pharmacy Service, Samsung Medical Center, Seoul, Republic of Korea
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Penttilä J, Kuusela T, Scheinin H. Analysis of rapid heart rate variability in the assessment of anticholinergic drug effects in humans. Eur J Clin Pharmacol 2005; 61:559-65. [PMID: 16133553 DOI: 10.1007/s00228-005-0953-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Accepted: 05/03/2005] [Indexed: 11/24/2022]
Abstract
Anticholinergic agents have widespread therapeutic indications in clinical medicine. In addition, certain other drug groups-such as neuroleptics, antidepressants and antihistamines-possess distinct anticholinergic properties that reduce tolerance and compliance. Especially in patients with heart disease, attention should be paid to cardiac anticholinergic drug effects. The analysis of short-term heart rate variability (HRV) provides a noninvasive tool to estimate vagal cholinergic outflow. In this review article, we present the basic principles of the most relevant techniques to study rapid HRV: the time domain analysis methods RMSSD and pNN50, and the high-frequency (HF) spectral component of HRV. We provide examples of previously reported effects of anticholinergic agents on these measures and also describe how adrenergic drugs may influence them. We have the following recommendations for a clinical pharmacologist investigating anticholinergic agents. (1) If the breathing rate of the study subject can be controlled during the assessment and the electrocardiogram recordings contain good-quality, stationary segments that are at least a few minutes long, then the HF power of HRV should be the method of choice. (2) During uncontrolled conditions, RMSSD should be included in the analyses, because it is less affected by changes in the respiratory pattern and it can be measured from shorter segments of electrocardiogram data. (3) Reduced short-term HRV suggests an anticholinergic, but not necessarily an antimuscarinic drug effect, since the inhibition of cholinergic vagal efferent activity may also originate from central or peripheral adrenergic influences.
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Affiliation(s)
- Jani Penttilä
- Department of Pharmacology and Clinical Pharmacology, University of Turku, Turku, Finland
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Kuusela TA, Jartti TT, Tahvanainen KUO, Kaila TJ. Prolongation of QT interval by terbutaline in healthy subjects. J Cardiovasc Pharmacol 2005; 45:175-81. [PMID: 15654267 DOI: 10.1097/01.fjc.0000152031.38750.b1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In a double-blind, randomized placebo-controlled crossover study, we characterized how terbutaline prolonged cardiac corrected QT interval (QTc). The study was carried out in six young and healthy male subjects in supine position. Escalating terbutaline doses were administered intravenously at infusion rates of 6 mL/h (10 microg terbutaline/min), 12 mL/h (20 microg terbutaline/min), and 18 mL/h (30 microg terbutaline/min). Terbutaline maximally prolonged QTc intervals on average by 60%, from 358 milliseconds (SD 28) to 456 milliseconds (SD 19). The effect was closely associated with a simultaneous decrease in plasma potassium concentration from 4.0 mmol/L (SD 0.1) to 2.5 mmol/L (SD 0.1). The final phase of slow ventricular repolarization, the interval between the apex and the end of T wave, was proven to be highly sensitive to the hypokalemic terbutaline actions, whereas the earlier repolarization phases were not strongly affected by terbutaline. Estimated by using the classic Nernst equation for membrane potentials, terbutaline-induced hypokalemia hyperpolarized ventricular myocardium from the resting level of -90 mV to -110 mV. The prolongation of QTc interval was related to ventricular hyperpolarization with a Pearson correlation coefficient of 0.91. Terbutaline-induced prolongation of QTc interval in healthy volunteers is in conformity with repolarization studies carried out in isolated canine heart ventricular preparations in which the cardiac ventricular cell membrane potential determines the duration of the final phase of slow ventricular repolarization.
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Affiliation(s)
- Tom A Kuusela
- Department of Physics, University of Turku, Turku, Finland.
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Anthracopoulos MB, Karatza AA, Davlouros PA, Chiladakis JA, Manolis AS, Beratis NG. Effects of two nebulization regimens on heart rate variability during acute asthma exacerbations in children. J Asthma 2005; 42:273-9. [PMID: 16032936 DOI: 10.1081/jas-200057895] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Analysis of heart rate variability (HRV) has been used to evaluate changes in sympathovagal balance. The present study was designed to investigate the influence of two therapeutic regimens on autonomic cardiovascular regulation during acute asthma exacerbations (AAE). Twenty children, 7-13 years of age, with moderate or severe AAE were randomized in two equal groups to receive either 0.15 mg/kg/dose salbutamol (group 1) or a combination of lower-dose salbutamol (0.10 mg/kg/dose) and ipratropium bromide (5 mcg/kg/dose) (group 2). Exacerbations were treated with three nebulizations (Tx) of either regimen given 20 minutes apart. HRV indices [total power, high-frequency component (HF), low-frequency component (LF), and LF:HF ratio] were analyzed at specific time intervals during the management of AAE. Therapy had a significant time-dependent main effect on total power (p = 0.001), LF (p < 0.0001), and HF (p = 0.005) but reached only borderline significance for LF:HF ratio (p = 0.053). The decrease in LF was more pronounced in group 2 vs. group 1 at 10 minutes post-Tx1 (p = 0.034) and at 10 minutes post-Tx2 (p = 0.05), but there was no significant difference between groups at 10 and 20 minutes post-Tx3. There were no significant differences between groups in any of the other HRV indices. Both regimens improved FEV1 (p = 0.0001) to the same magnitude. During AAE, three consecutive inhalation treatments with either high-dose salbutamol-only or lower-dose salbutamol plus ipratropium bromide combination, resulting in similar FEV1 improvement, cause domination of sympathetic over parasympathetic nervous system of similar overall magnitude but distinct patterns of HRV indices.
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Waring WS, Leigh RB. Haemodynamic responses to salbutamol and isometric exercise are altered in young adults with mild asthma. Eur J Clin Pharmacol 2005; 61:9-14. [PMID: 15785958 DOI: 10.1007/s00228-004-0880-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Accepted: 11/22/2004] [Indexed: 10/25/2022]
Abstract
OBJECTIVES Tolerance to the haemodynamic effects of regularly inhaled beta(2) agonists has been reported in a research setting. It is unclear whether cardiovascular responses in adults with asthma are influenced by their use in routine clinical practice. This study aimed to characterise the effects of acute salbutamol administration on systemic haemodynamics in adults with mild asthma who were receiving intermittent beta(2) agonist treatment. METHODS Ten patients with mild asthma and ten healthy age and sex-matched controls were recruited to a randomised placebo-controlled double-blind two-way crossover study. Each received salbutamol 200 mug or placebo, then performed sustained isometric handgrip exercise as an adrenergic cardiovascular stimulus. Heart rate and blood pressure responses were observed during rest and exercise, and cardiac index and systemic vascular resistance index were measured using non-invasive impedance cardiography. RESULTS Isometric exercise caused a greater increase in heart rate (12+/-3 vs. 8+/-3 bpm, P<0.01) and diastolic blood pressure (19+/-3 vs. 12+/-3 mmHg, P<0.01) in patients with asthma compared with healthy controls. Salbutamol administration significantly increased heart rate, blood pressure and cardiac index in healthy controls, but these responses were attenuated in patients with asthma. CONCLUSION These findings indicate that adults with asthma, who are receiving intermittent beta(2) agonist treatment, have a greater cardiovascular responses to sympathetic stimulation, and haemodynamic tolerance to acute salbutamol administration.
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Affiliation(s)
- W Stephen Waring
- Clinical Pharmacology Unit and Research Centre, The University of Edinburgh, Edinburgh, UK.
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Kuusela TA, Jartti TT, Tahvanainen KUO, Kaila TJ. Effects of terbutaline on peripheral vascular resistance and arterial compliance. J Cardiovasc Pharmacol 2004; 44:74-81. [PMID: 15175560 DOI: 10.1097/00005344-200407000-00010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In a double blind, randomized placebo-controlled crossover study we characterized how terbutaline affects the mean and short-term fluctuations of peripheral vascular resistance and arterial compliance. The study was carried out in six young and healthy male subjects in the supine and upright positions by recording continuously electrocardiography and finger arterial blood pressure. On average, large intravenous terbutaline doses reduce maximally by 50% the mean systolic-diastolic pressure decay time (windkessel time), by 30% the mean vascular resistance, and by 20% the mean arterial compliance. Terbutaline reduces differently the beat-to-beat variability of peripheral vascular resistance and arterial compliance. The effects can be explained by beta-adrenoceptor activation that mediates smooth muscle relaxation in small resistance arteries and large conduit arteries. Differences between vascular resistance and compliance lowering actions could be explained by differences in the beta-adrenoceptor-mediated vascular relaxation and sympathetically mediated vascular contraction between small and large arteries.
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Affiliation(s)
- Tom A Kuusela
- Department of Physics, University of Turku, Turku, Finland.
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Coons JC, Shullo M, Schonder K, Kormos R. Terbutaline for chronotropic support in heart transplantation. Ann Pharmacother 2004; 38:586-9. [PMID: 14982976 DOI: 10.1345/aph.1d440] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To report the use of oral terbutaline for chronotropic support in a patient who had undergone heart transplantation. CASE SUMMARY A 54-year-old white man received a heart transplant secondary to ischemic dilated cardiomyopathy. His clinical course was uncomplicated until postoperative day 10, when he became hemodynamically compromised despite inotropic therapy (BP 88/53 mm Hg, mean HR 80 beats/min) secondary to stage IIIa rejection. Although a continuous intravenous infusion of dobutamine was maintained, therapy with oral terbutaline 2.5 mg every 6 hours was initiated. Because the patient remained bradycardic on postoperative day 11 (HR 64 beats/min; mean 75), terbutaline was titrated to a dosage of 5 mg every 8 hours. Subsequently, an improvement in the hemodynamic profile (BP 140/78 mm Hg, mean HR 91 beats/min) was noted. Treatment with terbutaline was continued for 13 days and was well tolerated. DISCUSSION As of February 11, 2004, this is the first case, to our knowledge, to describe the use of oral terbutaline therapy for chronotropic support in the setting of acute rejection after heart transplantation. Terbutaline is a beta2-adrenergic agonist that may mediate its effects via direct beta2-receptor stimulation, baroreceptor-mediated increases in sympathetic tone, or via presynaptic beta2-stimulation. Although isoproterenol has been the mainstay of therapy for chronotropic support in this setting, its availability has been an issue in recent years. Terbutaline, therefore, may represent a useful alternative for chronotropic support in the setting of heart transplantation. CONCLUSIONS Terbutaline therapy did not appear to be associated with any significant adverse effects and warrants further application and study in this setting.
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Affiliation(s)
- James C Coons
- University of Pittsburgh Medical Center Health System, and University of Pittsburgh School of Pharmacy, Pittsburgh, PA, USA.
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Larsen PD, Elder DE, Tzeng YC, Campbell AJ, Galletly DC. Fractal characteristics of breath to breath timing in sleeping infants. Respir Physiol Neurobiol 2004; 139:263-70. [PMID: 15122992 DOI: 10.1016/j.resp.2003.11.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2003] [Indexed: 11/21/2022]
Abstract
We examined interbreath interval (IBI) time series of 19 term infants during active and quiet sleep for fractal properties using Fano factor analysis. For each time series we calculated the fractal exponent (alpha), comparing alpha for the original time series with two forms of surrogate data, a temporally independent surrogate set and an autoregressive surrogate set. alpha values were normally distributed between 0.79 and -0.22, and did not differ with sleep state. The fractal characteristics of the original time series were not retained in the temporally independent surrogate time series indicating that the distribution of intervals alone was not fractal, but were retained using autoregressive surrogates with an order of 10, suggesting that the fractal properties of the IBI time series were related to correlations between successive breaths. These observations suggest that some of the respiratory variability that occurs during sleep in infants, which in the past has been regarded as stochastic noise, may be the product of deterministic processes.
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Affiliation(s)
- P D Larsen
- Department of Surgery and Anaesthesia, Wellington School of Medicine, P.O. Box 7343, Wellington, New Zealand.
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Kuusela TA, Jartti TT, Tahvanainen KUO, Kaila TJ. Nonlinear methods of biosignal analysis in assessing terbutaline-induced heart rate and blood pressure changes. Am J Physiol Heart Circ Physiol 2002; 282:H773-83. [PMID: 11788429 DOI: 10.1152/ajpheart.00559.2001] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of this study was to characterize how different nonlinear methods characterize heart rate and blood pressure dynamics in healthy subjects at rest. The randomized, placebo-controlled crossover study with intravenous terbutaline was designed to induce four different stationary states of cardiovascular regulation system. The R-R interval, systolic arterial blood pressure, and heart rate time series were analyzed with a set of methods including approximate entropy, sample entropy, Lempel-Ziv entropy, symbol dynamic entropy, cross-entropy, correlation dimension, fractal dimensions, and stationarity test. Results indicate that R-R interval and systolic arterial pressure subsystems are mutually connected but have different dynamic properties. In the drug-free state the subsystems share many common features. When the strength of the baroreflex feedback loop is modified with terbutaline, R-R interval and systolic blood pressure lose mutual synchrony and drift toward their inherent state of operation. In this state the R-R interval system is rather complex and irregular, but the blood pressure system is much simpler than in the drug-free state.
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Affiliation(s)
- Tom A Kuusela
- Department of Physics, University of Turku, 20014 Turku, Finland.
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Mulder W, de Klerk S, Settels J, van Boxtel C. Beat-to-Beat Measurement of Cardiovascular Effects of a Single Subcutaneous Dose of Terbutaline in Healthy Subjects. Clin Drug Investig 2002; 22:593-600. [DOI: 10.2165/00044011-200222090-00004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Larsen PD, Galletly DC. Cardioventilatory coupling in heart rate variability: the value of standard analytical techniques. Br J Anaesth 2001; 87:819-26. [PMID: 11878681 DOI: 10.1093/bja/87.6.819] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In a group of spontaneously breathing anaesthetized subjects, we examined the ability of simple spectral and non-linear methods to detect the presence of cardioventilatory coupling in heart rate time series. Using the proportional Shannon entropy (H(RI-1)) of the RI(-1) interval (interval between inspiration and the preceding ECG R wave) as a measure of coupling, we found no correlation between H(RI-1) and either the fractal dimension or approximate entropy of the heart rate time series. We also observed no difference in the distribution of heart rate variability (HRV) spectral power in three frequency ranges (high, 0.15-0.45 Hz; low, 0.08-0.15 Hz; very low, 0.02-0.08 Hz) between uncoupled epochs and coupling patterns I, III and IV. Because of its association with low breathing frequencies, pattern II coupling epochs showed exaggerated low-frequency power as the high-frequency 'respiratory' peak fell into the low-frequency range. We conclude that coupling pattern is largely independent of autonomic tone and that these standard methods of HRV analysis are limited in their ability to detect the presence of cardioventilatory coupling in heart rate time series.
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Affiliation(s)
- P D Larsen
- Section of Anaesthesia, Wellington School of Medicine, New Zealand
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22
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Penttilä J, Helminen A, Jartti T, Kuusela T, Huikuri HV, Tulppo MP, Coffeng R, Scheinin H. Time domain, geometrical and frequency domain analysis of cardiac vagal outflow: effects of various respiratory patterns. CLINICAL PHYSIOLOGY (OXFORD, ENGLAND) 2001; 21:365-76. [PMID: 11380537 DOI: 10.1046/j.1365-2281.2001.00337.x] [Citation(s) in RCA: 358] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The purpose of this study was to compare the applicability of four different measures of heart rate variability (HRV) in the assessment of cardiac vagal outflow, with special reference to the effect of breathing pattern. The anticholinergic effects of an intravenous glycopyrrolate infusion (5 microg x kg(-1) x h(-1) for 2 h) during spontaneous and controlled (15 min(-1)) breathing rate were investigated in eight volunteers, and the effects of different fixed breathing rates (6-15-24 min(-1)) and hyperventilation in 12 subjects. Cardiac vagal activity was assessed by ECG recordings in which the following measures of HRV were computed: the high-frequency (HF) spectral component, the instantaneous RR interval (RRI) variability (SD1) analysed from the Poincaré plots, the percentage of differences between successive RRIs greater than 50 ms (pNN50), and the square root of the mean squared differences of successive RRIs (RMSSD). On average, glycopyrrolate reduced the HF spectral component by 99.8%, SD1 by 91.3%, pNN50 by 100% and RMSSD by 97.0%. The change of breathing pattern from controlled to spontaneous decreased significantly the HF component and pNN50, but did not affect SD1 or RMSSD. Rapid breathing rate (24 min(-1)) decreased the HF component, but had no effects on the other measures. A controlled breathing rate is needed for a reliable assessment of cardiac vagal outflow by the spectral analysis technique. The quantitative geometrical analysis of short-term RRI variability from the Poincaré plots and the time domain measure RMSSD were not significantly affected by changes in the breathing rate, suggesting that these indices are more suitable for the measurement of cardiac vagal outflow during the 'free-running' ambulatory conditions.
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Affiliation(s)
- J Penttilä
- Department of Pharmacology and Clinical Pharmacology, University of Turku, Turku, Finland
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23
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Jartti T. Asthma, asthma medication and autonomic nervous system dysfunction. CLINICAL PHYSIOLOGY (OXFORD, ENGLAND) 2001; 21:260-9. [PMID: 11318835 DOI: 10.1046/j.1365-2281.2001.00323.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Asthma is associated with autonomic nervous imbalance: an increased bronchial sensitivity to cholinergic constrictors and possibly a decreased sensitivity to beta2-adrenergic dilators have been reported in this disease. Also, non-adrenergic and non-cholinergic (NANC) mediators have a small regulatory effect on airway function. These mediators contribute to the pathogenesis of asthma not only by regulating smooth muscle tone in the airways but also by affecting pulmonary blood flow, endothelial permeability and airway secretions. In many studies increased parasympathetic responsiveness has been associated with clinical asthma or the worsening of asthma in adults. However, most of the studies in children have not found association between autonomic dysfunction and asthma. Therefore, the autonomic dysfunction in asthma may be related to more advanced disease or long-term asthma medication in adults. This article briefly reviews the relationships between airway inflammation, beta2-agonist, anticholinergic and glucocorticoid medication as well as autonomic nervous function in asthma.
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Affiliation(s)
- T Jartti
- The Department of Paediatrics, Turku University Central Hospital, Turku, Finland
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24
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Vesalainen RK, Ekholm EM, Jartti TT, Tahvanainen KU, Kaila TJ, Erkkola RU. Effects of tocolytic treatment with ritodrine on cardiovascular autonomic regulation. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1999; 106:238-43. [PMID: 10426643 DOI: 10.1111/j.1471-0528.1999.tb08237.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To study the acute effects of tocolytic treatment with intravenous ritodrine on cardiovascular autonomic regulation. DESIGN Validated methods to assess cardiovascular autonomic nervous function-heart rate and blood pressure variability and vagal cardiac baroreflex sensitivity-were measured before and during ritodrine infusion. SETTING Turku University Central Hospital, Turku, Finland. SAMPLE Twelve pregnant women admitted to hospital for threatened preterm labour. METHODS Electrocardiogram and continuous noninvasive finger blood pressure signals were recorded in each woman, resting in a supine position. Autoregressive spectrum analysis was used to quantify short term heart rate and blood pressure variability. Vagal cardiac baroreflex sensitivity was measured as the bradycardia response to an intravenous bolus injection of phenylephrine. MAIN OUTCOME MEASURES Vagal cardiac baroreflex sensitivity and spectrum analysis indices of short term heart rate and blood pressure variability. RESULTS Ritodrine significantly decreased vagal cardiac baroreflex sensitivity as well as total (0.00-0.40 Hz), low frequency (0.04-0.15 Hz) and high frequency (0.15-0.40 Hz) power bands of the heart rate variability spectrum. Ritodrine significantly increased mean heart rate and the low frequency power band of the systolic blood pressure variability spectrum. CONCLUSIONS In pregnant women with threatened preterm labour intravenous administration of ritodrine decreases vagal cardiac baroreflex sensitivity and vagal modulation of heart rate, and increases sympathetically mediated blood pressure variability. Decreased baroreflex sensitivity and heart rate variability are known to be associated with a poor prognosis in some patient groups, so the effects of ritodrine tocolysis may be unfavourable in women with impaired circulatory homeostasis.
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Affiliation(s)
- R K Vesalainen
- Department of Medicine, Turku University Central Hospital, Finland
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Hanratty CG, Silke B, Riddell JG. Evaluation of the effect on heart rate variability of a beta2-adrenoceptor agonist and antagonist using non-linear scatterplot and sequence methods. Br J Clin Pharmacol 1999; 47:157-66. [PMID: 10190650 PMCID: PMC2014165 DOI: 10.1046/j.1365-2125.1999.00862.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
AIMS To examine the impact on heart rate variability (HRV), of agonism or antagonism at the cardiac beta2-adrenoceptor in healthy volunteers, using standard time-domain summary statistics and non-linear methods (scatterplot and quadrant analysis). METHODS Under double-blind and randomised conditions (Latin square design), 17 normal volunteers received placebo, salbutamol (beta2-adrenoceptor partial agonist), ICI 118,551 (specific beta2-adrenoceptor antagonist), or salbutamol plus ICI 118,551. Single oral doses of medication (at weekly intervals) were administered at 22.30 h, with HRV assessed from the sleeping heart rates. RESULTS Salbutamol reduced the long-term (SDNN: 135 ms [120, 156], SDANN: 107 ms [89, 124]) time-domain indicators of HRV compared with placebo (SDNN: 39 [24, 55], SDANN 42 [29, 56], [mean difference [95% confidence intervals of difference]]). Alone, ICI 118,551 did not effect HRV, but in combination blocked the actions of salbutamol. Scatterplot length (944 ms [869, 1019]) and area (222*10(3) ms2 [191, 253]) were reduced by salbutamol compared with placebo; (length difference (164 [98, 230]) and area difference 59 [36, 83]). Scatterplot width (dispersion) was lower at both low (width RR-1 25% salbutamol 277 ms [261, 293]: salbutamol minus placebo 14 ms [0, 28]) and high (width 75% salbutamol 417 [391, 443]: salbutamol minus placebo 41 [20, 62]) heart rates. ICI 118,551 alone did not alter scatterplot parameters but in combination blocked the effect of salbutamol. Cardiac acceleration episodes (i.e. consecutive deltaRR and deltaRRn+1 shorten) were increased following salbutamol 7288 [6089, 8486] compared with placebo -1890 [-2600, -1179]; the beat-to beat difference (deltaRRn+1) was reduced after salbutamol compared with the other treatments. ICI 118,551 did not effect acceleration episodes but reduced the effect of salbutamol when used in combination. CONCLUSIONS Agonism at the cardiac beta2-adrenoceptor in healthy volunteers with salbutamol altered autonomic balance towards sympathetic dominance; this re-balancing was blocked by ICI 118,551 given in combination with salbutamol. However antagonism at the beta2-adrenoceptor with ICI 118,551 alone did not significantly alter the HRV. The beta2-adrenoceptor modulates HRV in healthy volunteers; the implications of agonism and antagonism at the beta2-adrenoceptor in cardiovascular disease states warrants further investigation.
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Affiliation(s)
- C G Hanratty
- Therapeutics and Pharmacology, The Whitla Division of Medicine, The Queen's University of Belfast, Medical Biology Centre
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26
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Jartti TT, Kaila TJ, Tahvanainen KU, Kuusela TA, Vanto TT, Välimäki IA. Altered cardiovascular autonomic regulation after salmeterol treatment in asthmatic children. CLINICAL PHYSIOLOGY (OXFORD, ENGLAND) 1998; 18:345-53. [PMID: 9715761 DOI: 10.1046/j.1365-2281.1998.00110.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The effects of therapeutic 4 weeks' inhaled salmeterol treatment on the cardiovascular and respiratory autonomic nervous regulation was studied in 11 asthmatic children using inhaled corticosteroid medication. The study followed a randomized, double-blind, placebo-controlled cross-over design. The salmeterol dose was 50 micrograms twice daily. The 4-week salmeterol treatment increased baseline heart rate, low-frequency/high-frequency (LF/HF) variability ratio of R-R intervals, LF variability of systolic arterial pressure (SAP) and maximum tidal volume during the deep breathing test, as well as morning and evening peak expiratory flow (PEF) values. The 4-week salmeterol treatment decreased baseline HF variability of R-R intervals. As a response to the acute 600 micrograms of salbutamol, the changes in heart rate, HF variability of R-R intervals and diastolic blood pressure were significantly smaller after 4 weeks' salmeterol treatment. In conclusion, 4 weeks' therapeutic salmeterol treatment decreases basal cardiovagal reactivity, increases sympathetic dominance in the cardiovascular autonomic balance and improves pulmonary function. A tolerance develops in the cardiovascular response but not in the bronchodilatory response.
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Affiliation(s)
- T T Jartti
- Department of Paediatrics, Turku University Hospital, Finland
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