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Rhythm Disturbances (rhythm + disturbance)
Kinds of Rhythm Disturbances Selected AbstractsHypersensitivity Myocarditis Presenting as Atrioventricular Block and Wide Complex Tachycardia in a ToddlerCONGENITAL HEART DISEASE, Issue 5 2008Neil Bhogal MD ABSTRACT A 13-month-old boy presented with acute onset of complete atrioventricular block and wide complex tachycardia but normal hemodynamics. Endomyocardial biopsy disclosed active myocarditis with eosinophils, suggesting a hypersensitivity reaction. With no treatment, the rhythm disturbance resolved within days of onset. Our patient's presentation and self-limited illness is unique. To our knowledge, this is only the second reported case of eosinophilic myocarditis in a young child or infant. [source] Is peri-operative cortisol secretion related to post-operative cognitive dysfunction?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2005L. S. Rasmussen Background:, The pattern of cortisol secretion is influenced by surgery. As cortisol can adversely affect neuronal function, this may be an important factor in the development of post-operative cognitive dysfunction (POCD). We hypothesized that the incidence of POCD would be related to changes in cortisol level. Methods:, We studied 187 patients aged over 60 years undergoing major non-cardiac surgery with general or regional anaesthesia. Saliva cortisol levels were measured pre-operatively and at 1 day, 7 days and 3 months post-operatively in the morning (08.00 h) and in the afternoon (16.00 h) using salivettes. Cognitive function was assessed pre-operatively, on day 7 and at 3 months using four neuropsychological tests. POCD was defined as a combined Z score of greater than 1.96. Results:, After surgery, salivary cortisol concentrations increased significantly. POCD was detected in 18.8% of subjects at 1 week and in 15.2% after 3 months. The pre-operative ratios between the morning and afternoon cortisol concentrations (am/pm ratios) were 2.8 and 2.7 in patients with POCD at 1 week vs. those without POCD at 1 week, respectively. The am/pm ratios decreased significantly post-operatively to 1.9 and 1.6 at 1 week, respectively (P = 0.02 for both). In an analysis considering all am/pm ratios, it was found that the persistent flattening in am/pm ratio was significantly related to POCD at 1 week. Conclusion:, The pattern of diurnal variation in cortisol level was significantly related to POCD. Thus, circadian rhythm disturbance or metabolic endocrine stress could be an important mechanism in the development of cognitive dysfunction after major surgery. [source] Circadian rest-activity rhythm is altered in Parkinson's disease patients with hallucinationsMOVEMENT DISORDERS, Issue 8 2008Daisy L. Whitehead PhD Abstract The sleep-wake cycle in Parkinson's Disease (PD) is profoundly disrupted, but less is known about circadian rhythm in PD and its relationship to other important clinical features. This study compared rest-activity rhythms in healthy older adults and PD patients with and without hallucinations. Twenty-nine older adults and 50 PD patients (27 with hallucinations, 23 without) were assessed using wrist-worn actigraphy for 5 days. Disease-related and cognitive data were also collected. PD patients demonstrated reduced amplitude of activity (F = 12.719, P < 0.01) and increased intradaily variability (F = 22.005, P < 0.001), compared to healthy older adults, independently of age, and cognitive status. Hallucinators showed lower interdaily stability (F = 7.493, P < 0.01) significantly greater activity during "night-time" (F = 6.080, P < 0.05) and significantly reduced relative amplitude of activity (F = 5.804, P < 0.05) compared to nonhallucinators, independently of clinical factors including motor fluctuations. PD patients with hallucinations display altered rest-activity rhythm characterized by an unpredictable circadian pattern across days, likely arising from damage to brainstem and hypothalamic sleep centers. Treatment of sleep and rest-activity rhythm disturbance is an important target in Parkinson's Disease. © 2008 Movement Disorder Society. [source] Actigraphic assessment of the circadian rest,activity rhythm in elderly patients hospitalized in an acute care unitPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 1 2003Stéphane Vinzio RD Abstract Hospitalization for acute illness is a major risk factor of rest,activity rhythm disturbance among elderly subjects. The rest,activity rhythm is disturbed by the acute illness, aging and hospital environment. The purpose of this study is to assess the rest,activity rhythm and light exposure (using a wrist worn actigraph) of 10 patients (mean age 81 years, seven females) admitted on an acute care unit, suffering from cardiac, respiratory or renal acute disease. A non-parametric method was used to analyze activity data. With an improvement of the underlying diseases, the mean relative amplitude of rhythm increased from 0.31 ± 0.19 for the first 5-day period after admission to 0.54 ± 0.21 for the second period before discharge (P < 0.05). The amount of time at night spent above a lighting threshold of 50 lux decreased from 31.4 to 12.3 min between the two periods. The rhythm of elderly subjects hospitalized in the acute care unit is severely altered during the initial period and is progressively resynchronized following clinical improvement. Under the acute underlying disease and/or aging, environmental conditions (light, noise) should be considered to maintain regular rest,activity rhythm. [source] Single Nucleotide Polymorphisms and Haplotype of Four Genes Encoding Cardiac Ion Channels in Chinese and their Association with ArrhythmiaANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2008Yu Zhang Ph.D. Background: Many studies revealed that variations in cardiac ion channels would cause cardiac arrhythmias or act as genetic risk factors. We hypothesized that specific single nucleotide polymorphisms in cardiac ion channels were associated with cardiac rhythm disturbance in the Chinese population. Method: We analyzed 160 nonfamilial cardiac arrhythmia patients and 176 healthy individuals from which 81 individuals were selected for association study, and a total of 19 previously reported SNPs in four cardiac ion channel genes (KCNQ1, KCNH2, SCN5A, KCNE1) were genotyped. Results: The frequency of KCNQ1 1638G>A, as well as the haplotype harboring KCNQ1 1638A, KCNQ1 1685 + 23G and 1732 + 43T (haplotype AGT) was significantly higher in healthy controls than in arrhythmia patients. This finding implicated that this haplotype (AGT) might be a protective factor against arrhythmias. Conclusions: Our study provided important information to elucidate the effect of SNPs of cardiac ion channel genes on channel function and susceptibility to cardiac arrhythmias in Chinese population. [source] Thaliporphine protects ischemic and ischemic-reperfused rat hearts via an NO-dependent mechanismDRUG DEVELOPMENT RESEARCH, Issue 3 2001Li-Man Hung Abstract In ischemia or ischemia-reperfusion (I/R), nitric oxide (NO) can potentially exert several beneficial effects. Thaliporphine, a natural alkaloid with Ca2+ channel-activating and Na+/K+ channel-blocking activities, increased NO levels and exerted cardioprotective action in ischemic or I/R rats. The role of NO in the cardioprotective actions of thaliporphine was assessed. The severity of rhythm disturbances and mortality in anesthetized rats with either coronary artery occlusion for 30 min, or 5 min followed by 30-min reperfusion, were monitored and compared in thaliporphine- vs. placebo-treated groups. Thaliporphine treatment significantly increased NO and decreased lactate dehydrogenase (LDH) levels in the blood during the end period of ischemia or I/R. These changes in NO and LDH levels by thaliporphine were associated with a reduction in the incidence and duration of ventricular tachycardia (VT) and ventricular fibrillation (VF) during ischemic or I/R period. The mortality of animals was also completely prevented by 1 × 10,8 moles/kg of thaliporphine. In animals subjected to 4 h of left coronary artery occlusion, 1 × 10,7 moles/kg of thaliporphine dramatic reduced cardiac infarct zone from 46 ± 6% to 7.1 ± 1.9%. Inhibition of NO synthesis with 3.7 × 10,6 moles/kg of N, -nitro-L-arginine methyl ester (L-NAME) abolished the beneficial effects of thaliporphine during 30 min or 4 h myocardial ischemia. However, the antiarrhythmic activity and mortality reduction efficacy of thaliporphine during reperfusion after 5 min of ischemia was only partially antagonized by L-NAME. These results showed that thaliporphine efficiently exerted the cardioprotections either in acute or prolonged coronary artery occlusion or occlusion-reperfusion situations. The fact that thaliporphine induced cardioprotective effects were abrogated by L-NAME indicates that NO is an important mediator for the cardioprotective effects of thaliporphine in acute or prolonged ischemia, whereas antioxidant activities may contribute to the protection of I/R injury. Drug Dev. Res. 52:446,453, 2001. © 2001 Wiley-Liss, Inc. [source] Therapy of circadian rhythm disorders in chronic fatigue syndrome: no symptomatic improvement with melatonin or phototherapyEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 11 2002G. Williams Abstract Background Patients with chronic fatigue syndrome (CFS) show evidence of circadian rhythm disturbances. We aimed to determine whether CFS symptoms were alleviated by melatonin and bright-light phototherapy, which have been shown to improve circadian rhythm disorders and fatigue in jet-lag and shift workers. Design Thirty patients with unexplained fatigue for > 6 months were initially assessed using placebo and then received melatonin (5 mg in the evening) and phototherapy (2500 Lux for 1 h in the morning), each for 12 weeks in random order separated by a washout period. Principal symptoms of CFS were measured by visual analogue scales, the Shortform (SF-36) Health Survey, Mental Fatigue Inventory and Hospital Anxiety and Depression Scale. We also determined the circadian rhythm of body temperature, timing of the onset of melatonin secretion, and the relationship between these. Results Neither intervention showed any significant effect on any of the principal symptoms or on general measures of physical or mental health. Compared with placebo, neither body temperature rhythm nor onset of melatonin secretion was significantly altered by either treatment, except for a slight advance of temperature phase (0·8 h; P = 0·04) with phototherapy. Conclusion Melatonin and bright-light phototherapy appear ineffective in CFS. Both treatments are being prescribed for CFS sufferers by medical and alternative practitioners. Their unregulated use should be prohibited unless, or until, clear benefits are convincingly demonstrated. [source] Circadian rhythm disturbances in depression,HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 7 2008Anne Germain Abstract Objective The aim of this article is to review progress in understanding the mechanisms that underlie circadian and sleep rhythms, and their role in the pathogenesis and treatment of depression. Methods Literature was selected principally by Medline searches, and additional reports were identified based on ongoing research activities in the authors' laboratory. Results Many physiological processes show circadian rhythms of activity. Sleep and waking are the most obvious circadian rhythms in mammals. There is considerable evidence that circadian and sleep disturbances are important in the pathophysiology of mood disorders. Depressed patients often show altered circadian rhythms, sleep disturbances, and diurnal mood variation. Chronotherapies, including bright light exposure, sleep deprivation, and social rhythm therapies, may be useful adjuncts in non-seasonal and seasonal depression. Antidepressant drugs have marked effects on circadian processes and sleep. Conclusions Recent progress in understanding chronobiological and sleep regulation mechanisms may provide novel insights and avenues into the development of new pharmacological and behavioral treatment strategies for mood disorders. Copyright © 2008 John Wiley & Sons, Ltd. [source] Environmental risk assessment of human pharmaceuticals in the European Union: A case study with the ,-blocker atenololINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue S1 2010Anette Küster Abstract ,-Adrenergic receptor blockers (,-blockers) are applied to treat high blood pressure, ischemic heart disease, and heart rhythm disturbances. Due to their widespread use and limited human metabolism, ,-blockers are widely detected in sewage effluents and surface waters. ,-Adrenergic receptors have been characterized in fish and other aquatic animals, so it can be expected that physiological processes regulated by these receptors in wild animals may be affected by the presence of ,-blockers. Because ecotoxicological data on ,-blockers are scarce, it was decided to choose the ,-blocker atenolol as a case study pharmaceutical within the project ERAPharm. A starting point for the assessment of potential environmental risks was the European guideline on the environmental risk assessment of medicinal products for human use. In Phase I of the risk assessment, the initial predicted environmental concentration (PEC) of atenolol in surface water (500,ng L,1) exceeded the action limit of 10,ng L,1. Thus, a Phase II risk assessment was conducted showing acceptable risks for surface water, for groundwater, and for aquatic microorganisms. Furthermore, atenolol showed a low potential for bioaccumulation as indicated by its low lipophilicity (log KOW,=,0.16), a low potential for exposure of the terrestrial compartment via sludge (log KOC,=,2.17), and a low affinity for sorption to the sediment. Thus, the risk assessment according to Phase II-Tier A did not reveal any unacceptable risk for atenolol. Beyond the requirements of the guideline, additional data on effects and fate were generated within ERAPharm. A 2-generation reproduction test with the waterflea Daphnia magna resulted in the most sensitive no-observed-effect concentration (NOEC) of 1.8,mg L,1. However, even with this NOEC, a risk quotient of 0.003 was calculated, which is still well below the risk threshold limit of 1. Additional studies confirm the outcome of the environmental risk assessment according to EMEA/CHMP (2006). However, atenolol should not be considered as representative for other ,-blockers, such as metoprolol, oxprenolol, and propranolol, some of which show significantly different physicochemical characteristics and varying toxicological profiles in mammalian studies. Integr Environ Assess Manag 2010;6:514,523. © 2009 SETAC [source] Behavioral profile of Alzheimer's disease in Chinese elderly , a validation study of the Chinese version of the Alzheimer's disease behavioral pathology rating scaleINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 4 2001Linda C. W. Lam Abstract Objectives This study aims to examine the psychometric properties of the Chinese version of the Alzheimer's disease behavioral pathology rating scale (CBehave-AD) and the behavioral profile of Chinese patients with AD. Methods Seventy-one subjects with NINCDS-ADRDA diagnosis of probable and possible AD were assessed for validation of the CBehave-AD. A behavioral symptom frequency checklist, the Chinese version of the Blessed Roth dementia scale (CDS) and the Cantonese version of the Mini-Mental State Examination (CMMSE) were used for comparison. An extended sample of 120 AD patients was then evaluated with the CBehave-AD. Results High correlations between the CBehave-AD and checklist scores were found (paranoid and delusional ideation, hallucinations, activity disturbances, aggressiveness and diurnal rhythm disturbances). The scale also demonstrated satisfactory inter-rater and test-retest reliabilities. The mean (SD) CMMSE score of the 120 patients was 9.4 (7.1). Among them, 32% have delusions, 15% had hallucinations, 54% had activity disturbances, 61% had aggressive behavior, 44% had sleep disturbance, 24% had affective disturbances, 19% had anxiety and phobias. Delusional ideation was significantly associated with hallucinations, aggressiveness, and affective disturbances. Diurnal rhythm disturbances were associated with activity disturbances and aggressiveness. CBehave-AD total scores were not significantly correlated with severity of AD, but individual symptom categories showed different pattern of correlation. Delusions, hallucinations, anxiety and phobias were significantly correlated with dementia staging. Conclusion The findings suggest that the CBehave-AD is a valid assessment tool for behavioral disturbances in patients with AD. Variable associations between different symptom categories and dementia staging suggest a need for further exploration of the complex interactions between behavioral and cognitive disturbances in dementia. Copyright © 2001 John Wiley & Sons, Ltd. [source] Assessment of an ECG event recorder in healthy dogs in a hospital environmentJOURNAL OF SMALL ANIMAL PRACTICE, Issue 4 2003J. M. Eastwood Ambulatory electrocardiography techniques are superior to standard electrocardiography in evaluating rhythm disturbances in dogs with episodic weakness or collapse. Disadvantages include cumbersome equipment, short recording periods and an inherent delay in trace analysis. A small programmable cardiac event recorder with combined automatic and owner-triggered recording capability was evaluated in 13 healthy dogs in a hospital environment. The unit was well tolerated and produced diagnostic recordings directly to a personal computer, with useful information about continuous heart rate. It detects premature complexes, pauses and bradycardias according to programmed detection thresholds. These events were counted frequently but trace review revealed concerns regarding specificity. Recordings were often triggered by sinus arrhythmia, sinus tachycardia and unclassifiable rate changes rather than by clinically significant arrhythmias. Correct detection of ventricular ectopic complexes, a single supraventricular premature complex, sinus arrest and second-degree atrioventricular block occurred in individual dogs. Visual review of all automatically recorded events was essential and significantly increased the time required for event recording analysis. Manual recordings might be more useful and the overall results suggest that further studies are warranted to evaluate the system in clinical cases in the home environment. [source] Postoperative elevated cortisol excretion is not associated with suppression of 6-sulfatoxymelatonin excretionACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2005J. Derenzo This study tests the hypothesis that elevated postoperative excretion of cortisol is associated with suppression of the nocturnal excretion of 6-sulfatoxymelatonin, the chief metabolite of the circadian hormone, melatonin. Postoperative patients demonstrate circadian rhythm disturbances and suppression of nocturnal melatonin plasma concentration. Since the nocturnal surge in melatonin concentration in normal volunteers is time-locked to the circadian nadir of cortisol concentration, perhaps the attenuation of the nocturnal melatonin surge in postoperative patients results from prolonged elevation in the plasma cortisol concentration. In this observational study performed in 21 patients having unilateral hip or knee arthroplasty, urine was collected every 4 h for the first 48 h after surgery for measurement of urinary 6-sulfatoxymelatonin (EIA) and free cortisol (RIA) excretion. The total (P < 0.05) and peak (P < 0.02) nocturnal 6-sulfatoxymelatonin excretions were lower on the first than the second postoperative night. The nocturnal cortisol nadir preceded the 6-sulfatoxymelatonin surge in 20% of the subjects on night 1 and in 75% of the subjects on night 2. The lack of a consistent relationship between the magnitude or timing of cortisol excretion and 6-sulfatoxymelatonin excretion suggests that cortisol does not mediate postoperative 6-sulfatoxymelatonin suppression. [source] 24 Electrogastrography EGG in pancreas diabetesNEUROGASTROENTEROLOGY & MOTILITY, Issue 6 2006E SCHAFER Background:, Timing and criteria of testing for gastric dysmotility in pancreatic diabetes is not well established. Aim:, To investigate the pattern of EGG and autonomic neuropathy (AN) in patients with pancreas diabetes mellitus to clarify the relationship between autonomic neuropathy, alcohol consumption, glucose homeostasis, diabetes duration, and EGG. Patients and methods:, Thirty patients with pancreas diabetes mellitus were enrolled into the study. Mean duration of diabetes mellitus was 11 (0,25) years, mean blood glucose levels: 8.13 ± 2.7 mmoll,1, HbA1c 8.3 ± 2.96%; 25/30 patients were treated with insulin, the others were on rigorous diet, all of them received high dose pancreatin substitution therapy. Ten matched controls without diabetes and pancreatic insufficiency were also examined. AN was evaluated by the cardiovascular reflex tests according to the Ewing's criteria (Diab. Care 8 (5): 491,497, 1985.), EGG was monitored for 30,30 min in both fasting and in postprandial states, using a Digitrapper EGG (Synectic Med., Stockholm). EGG rhythm disturbances (bradygastria: 0,2 cpm, tachygastria: 4,10 cpm) and meal evoked EGG signal amplitude (power) changes were determined. Results:, 9/30 pts had mild to moderate parasympathetic AN, 1/30 pts had sympathetic AN, 5/30 pts had both parasympathetic and sympathetic AN; 17/30 pts demonstrated myoelectric abnormalities: 5/30 pts had predominant bradygastria, 3/30 tachygastria, and in other 9/30 pts only an absence of increase in the postprandial signal amplitude was found. Overall, 7/30 pts with abnormal EGG did not demonstrated AN. Abnormal EGG showed no correlation with actual blood sugar values or HbA1c, but it was associated with diabetes duration more than 10 years. Conclusion:, Our results suggest that beside neuropathy other factors such as alcohol toxicity, sympathetic and parasympathetic imbalance or long-term inappropriate glucose metabolism may be involved in the gastric myoelectric abnormalities provoked by pancreas diabetes. [source] Electrogastrography: a document prepared by the gastric section of the American Motility Society Clinical GI Motility Testing Task ForceNEUROGASTROENTEROLOGY & MOTILITY, Issue 2 2003H. P. Parkman Abstract The objective of this document is to present the consensus opinion of the American Motility Society Clinical GI Motility Testing Task Force on the performance and clinical utility of electrogastrography (EGG). EGG is a non-invasive means of recording human gastric myoelectrical activity or slow waves from cutaneous leads placed over the stomach. In healthy volunteers, EGG tracings exhibit sinusoidal waveforms with a predominant frequency of 3 cycles per minute (cpm). Clinical studies have shown good correlation of these cutaneous recordings with those acquired from serosally implanted electrodes. The amplitude of the EGG waveform increases with ingestion of caloric or non-caloric meals. Some patients with nausea, vomiting, or other dyspeptic symptoms exhibit EGG rhythm disturbances or blunting of meal-evoked EGG signal amplitude increases. These abnormalities correlate to some degree with delayed gastric emptying of solids. In selected patients, EGG may be complementary to gastric emptying testing. To date, no therapies have convincingly demonstrated in controlled studies that correcting abnormalities detected by EGG improves upper gastrointestinal symptoms. Proposed clinical indications for performance of EGG in patients with unexplained nausea, vomiting and dyspeptic symptoms must be validated by prospective controlled investigations. [source] Improvement in behavioral symptoms and advance of activity acrophase after short-term bright light treatment in severe dementiaPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2004ARVID SKJERVE psyd Abstract Ten elderly subjects with severe dementia were given bright light (5000,8000 lux) for 45 min each morning for 4 weeks. Two rating scales of behavioral symptoms in dementia were used as outcome measures: Cohen-Mansfield Agitation Inventory (CMAI) and Behavior Pathology In Alzheimer's Disease Rating Scale (BEHAVE-AD), a scale for sleep,wake disturbances, and actigraphy to monitor activity rhythm. Behavioral symptoms improved with treatment. No changes in sleep,wake measures were found. There was an advance of the activity rhythm acrophase during treatment. These results suggest that short-time bright light improves behavioral symptoms and aspects of activity rhythm disturbances even in severely demented subjects. [source] The Effect of Sleep Apnea on QT Interval, QT Dispersion, and ArrhythmiasCLINICAL CARDIOLOGY, Issue 6 2010Kitti Barta MD Background QT interval (QT) and QT dispersion (QTd) are electrocardiograph (ECG) parameters for the evaluation of myocardial repolarization. The inhomogeneity of ventricular repolarization is associated with ventricular arrhythmias. An increased QT, QTd, and increased incidence of nocturnal cardiac rhythm disturbances have been described in patients with obstructive sleep apnea (OSA), while other investigators did not find a relationship between ventricular arrhythmias and OSA. Hypothesis The aim of this study was to examine the occurrence of ventricular arrhythmias and to measure QT parameters in patients with untreated OSA using an ambulatory Holter-ECG. Methods A total of 25 patients with untreated OSA were studied. After routine biochemical investigation and 2-dimensional, M-mode echocardiography, a 24-hour Holter-ECG was recorded to detect cardiac arrhythmias and QT parameters. QT parameters were measured by the QT Guard system. Results Only the QT interval increased significantly during the nighttime period (nocturnal QT interval: 423.1 ± 34.6 ms, daytime QT interval: 381.6 ± 33.8 ms, 24-hour QT interval: 394.7 ± 31.1 ms). However, during the nighttime QT interval (422.8 ± 14.9 ms), QTd (31.2 ± 11.0 ms) and QT dispersion (30.5 ± 10.2 ms) did not show any change compared to 24-hour (QTc interval: 423.7 ± 14.2 ms, QTd: 28.8 ± 9.4 ms, QTcd: 30.5 ± 9.43 ms) and daytime levels (QTc interval: 423.9 ± 14.3 ms, QTd: 27.3 ± 10.7 ms, QTcd: 29.9 ± 11.1 ms). None of the patients had ventricular arrhythmias. Conclusions QTd and QTcd did not increase during the nighttime period. Our study did not show an increased risk of ventricular arrhythmias in this population during the monitoring period. Copyright © 2010 Wiley Periodicals, Inc. [source] | ||||||||||||||||||||||