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Holter Monitoring (holter + monitoring)
Kinds of Holter Monitoring Selected AbstractsMicrovolt T-Wave Alternans during Holter Monitoring in Children and AdolescentsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010Leonid Makarov M.D. Background: Time-domain microvolt T-wave alternans (TWA) has been described as a noninvasive marker of sudden cardiac death in adults. The incidence of TWA in pediatric populations has not been defined well. The aim of the study was to determine peculiarities of TWA in children. Methods: We examined 68 healthy patients,newborns (20) and children in age group of 7,17 years (48),and 85 pediatric patients: ventricular premature beats,65; dilated cardiomyopathy (DCMP),2; long QT syndrome (LQTS),10; Brugada syndrome (BrS),5, catecholaminergic ventricular tachycardia (CVT),3. All underwent Holter monitoring (HM) with definition of the peak value of TWA by modified moving average method. Results: In healthy newborns, TWA was 32 ± 8 (12,55) ,V (HR 123,156 bmp). In healthy children (7,17 years) it was 30 ± 11 (10,l 55) ,V, (HR 64,132 bmp) without any differences between boys and girls. In all group of patients, TWA were significantly higher (P < 0.05) than in healthy. Circadian peak of TWA was found (90%) in a second part of day and at sleep (8%). Among them 60% (LQTS, BrS, and DCPM) had TWA > 55 ,V. Conclusion: Time-domain TWA during HM in children was independent of age, gender, and heart rate. In 94% healthy children, values of TWA do not exceed 55 ,V but 20,50% children with cardiac pathology had TWA more than 55 ,V. Night circadian type of TWA in diseases with risk of life-threatening arrhythmias associated with TWA was more than 55 ,V. Ann Noninvasive Electrocardiol 2010;15(2):138,144 [source] Pacemaker Memory Data Compared to Twenty-Four-Hour Holter Monitoring in Patients with VVI Pacemakers and Chronic Atrial FibrillationANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2005Michal Chudzik M.D., Ph.D. Background: In light of the results from the AFFIRM trial, the "rate control" strategy has become an accepted treatment modality for patients with atrial fibrillation (AF). Establishing effective rate control requires long-term monitoring of the heart rate. The aim of the study was to compare the heart rate and rhythm monitoring capabilities of the pacemaker memory data (PMD) algorithm and traditional twenty-four-hour Holter monitoring. Methods: The study included 55 patients with chronic AF and a permanent VVI pacemaker. The mean and maximum heart rate as well as the percentage of sensed and paced events obtained from the twenty-four-hour Holter were compared with the results retrieved from PMD, started simultaneously. The study was performed over two consecutive days with pacemakers programmed in VVI 40 and 80 bpm mode. Results: Data retrieved from PMD regarding percentage of sensed and paced episodes as well as mean heart rate strongly correlated with data obtained from twenty-four-hour Holter monitoring. The maximum heart rate reported by PMD was significantly higher than that found in the Holter. Conclusions: PMD provides accurate information regarding long-term monitoring of heart rate in patients with AF who have an implanted permanent pacemaker and thus may facilitate optimized drug therapy to achieve rate control of AF. [source] Evaluation of Patients with Palpitations: Cardiac Event Recorder Versus 48-hour Holter MonitoringANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2000Ewa Makowska M.D. Objectives: (1) To compare a diagnostic yield of cardiac event recorders with that of 48-hour Holler monitoring, (2) to determine the etiologies of palpitations, and (3) to assess an optimal duration of using an event recorder by a patient. Background: Palpitation is a common symptom which accounts for 16% of total complaints reported by patients in general medical settings. An ambulatory Holter ECG monitoring or an event recorder can be used to establish the cause of palpitations. Methods: (1)The study group consisted of 33 consecutive patients (24 females, 9 males, mean age 50 ± 32 years) with undiagnosed attacks of palpitations, occurring at least once per month. Each patient was randomly allocated to use either an event monitor or 48-hour Holler monitoring. The patient kept the event monitor for 4 weeks. After the first monitor was returned, the patient was given the other device. Results: Holter monitoring determined the etiology of palpitations in 11 (33%) patients, and the event recorder in 21 (64%) patients (P = 0.0138). In the whole study group, the etiology of palpitations was disclosed in 23 (70%) patients. The diagnosis was possible using Holler ECG monitoring in only 2 (9%) patients, whereas the event recorder revealed the underlying mechanism of palpitations in 12 (52%) patients (P = 0.0007). In nine (39%) patients both methods were able to disclose the eliology of palpitations. The findings of 117 recordings obtained using an event recorder during palpitations were atrial fibrillation in 10 (9%), narrow QRS tachycardia in 4 (3%), frequent supraventricular eclopy in 17 (15%), frequent ventricular eclopy in 6 (5%), and episodes of palpitations sinus rhythm were recorded in the remaining 80 (68%). Of patients who experienced episodes of palpitations while using an event recorder, the earliest recording was obtained on the first day of the study, and the latest on the 18 day of using the event recorder. Conclusions: (1) The cardiac event recorders yield more diagnoses than 48-hour Holter monitoring in patients with palpitations occurring at least once per month, (2) in this group of patients the event recorder provided a diagnostic ECG recording during the first 18 days of using the device, and (3) in the majority (57%) of patients a normal sinus rhythm was recorded during episodes of palpitations. A.N.E. 2000;5(4):315,321 [source] The Utility of Holter Monitoring Compared to Loop Recorders in the Evaluation of Syncope and PresyncopeANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2000Andrew D. Krahn M.D. Background: Holter monitoring is frequently used to assess patients with syncope, but rarely provides a diagnosis. Newer loop recorders provide the opportunity for prolonged electrocardiographic monitoring to enhance diagnostic yield. Methods: The results of 232 Holter monitors and 81 loop recordings performed for the investigation of syncope or presyncope were reviewed for indication, patient demographics, and presence and type of symptoms and/or arrhythmias. The results were classified as (1) symptom-arrhythmia correlation, (2) clinically useful information (group 1 plus those excluding arrhythmic syncope, and those demonstrating asymptomatic serious arrhythmias) and (3) unhelpful (asymptomatic and no serious arrhythmias). Results: Loop recorders provided a symptom-arrhythmia correlation in 11.1% of patients compared to only 0.4% in the Holter group (P < 0.0001). Clinically useful information was obtained in 54.3% of loop patients compared to 27.6% in the Holter group (P < 0.0001). Technical problems occurred in 0.4% of the Holter patients and in 3.7% of loop patients (P = 0.05). Classification was difficult in seven patients in the Holter group; two experienced symptoms during sinus rhythm but also had a serious asymptomatic arrhythmia, and five patients had 6,10 beats of asymptomatic ventricular tachycardia at a rate < 160 beats/min. Conclusion: Loop recording was well tolerated and superior to Holter monitoring in providing a symptom-arrhythmia correlation or clinically useful information in patients with syncope and presyncope. An initial approach with a loop-recording device should be employed in these patients. [source] Impaired glucose regulation, elevated glycated haemoglobin and cardiac ischaemic events in vascular surgery patientsDIABETIC MEDICINE, Issue 3 2008H. H. H. Feringa Abstract Aims Cardiac morbidity and mortality is high in patients undergoing high-risk surgery. This study investigated whether impaired glucose regulation and elevated glycated haemoglobin (HbA1c) levels are associated with increased cardiac ischaemic events in vascular surgery patients. Methods Baseline glucose and HbA1c were measured in 401 vascular surgery patients. Glucose < 5.6 mmol/l was defined as normal. Fasting glucose 5.6,7.0 mmol/l or random glucose 5.6,11.1 mmol/l was defined as impaired glucose regulation. Fasting glucose , 7.0 or random glucose , 11.1 mmol/l was defined as diabetes. Perioperative ischaemia was identified by 72-h Holter monitoring. Troponin T was measured on days 1, 3 and 7 and before discharge. Cardiac death or Q-wave myocardial infarction was noted at 30-day and longer-term follow-up (mean 2.5 years). Results Mean (± sd) level for glucose was 6.3 ± 2.3 mmol/l and for HbA1c 6.2 ± 1.3%. Ischaemia, troponin release, 30-day and long-term cardiac events occurred in 27, 22, 6 and 17%, respectively. Using subjects with normal glucose levels as the reference category, multivariate analysis revealed that patients with impaired glucose regulation and diabetes were at 2.2- and 2.6-fold increased risk of ischaemia, 3.8- and 3.9-fold for troponin release, 4.3- and 4.8-fold for 30-day cardiac events and 1.9- and 3.1-fold for long-term cardiac events. Patients with HbA1c > 7.0% (n = 63, 16%) were at 2.8-fold, 2.1-fold, 5.3-fold and 5.6-fold increased risk for ischaemia, troponin release, 30-day and long-term cardiac events, respectively. Conclusions Impaired glucose regulation and elevated HbA1c are risk factors for cardiac ischaemic events in vascular surgery patients. [source] Heart Rate Variability in Emergency Department Patients with SepsisACADEMIC EMERGENCY MEDICINE, Issue 7 2002Douglas Barnaby MD Abstract Objective: To test the hypothesis that heart rate variability (HRV) can provide an early indication of illness severity among patients presenting to the emergency department (ED) with sepsis. Methods: The authors enrolled a convenience sample of 15 ED patients meeting the American College of Chest Physicians/Society of Critical Care Medicine criteria for sepsis. Each patient had continuous Holter monitoring performed in the ED. Acute Physiology and Chronic Health II (APACHE II) and Sequential Organ Failure (SOFA) scores were calculated for the day of presentation. Holter tapes obtained in the ED were analyzed off-line to calculate HRV variables for the 5-minute segment with the least artifact and non-sinus beats. These variables were correlated with APACHE II and SOFA scores. Results: LFnu (normalized low-frequency power), an assessment of the relative sympathetic contribution to overall HRV, was correlated with increased illness severity as calculated using APACHE II (r = -0.67, r2= 0.43) and SOFA (r = -0.80, r2= 0.64) scores. LF/HF ratio (low-frequency/high-frequency ratio), a measure of sympathovagal balance, was correlated with the SOFA score [r = -0.54 (95% CI = -0.83 to -0.01), r2= 0.29]. All five patients who required critical care monitoring or ventilatory support or who died during the first 5 days of their hospitalization had LFnu values below 0.5 and LF/HF ratios less than 1.0. None of the patients with measurements greater than these threshold values died or required these interventions during the five days following admission. Conclusions: A single variable, LFnu, which reflects sympathetic modulation of heart rate, accounted for 40-60% of the variance in illness severity scores among patients presenting to the ED with sepsis. HRV, as reflected in LFnu and the LF/HF ratio and measured with a single brief (5-minute) period of monitoring while in the ED, may provide the emergency physician with a readily available, noninvasive, early marker of illness severity. The threshold effect of LFnu and LF/HF in the prediction of early clinical deterioration was an unexpected finding and should be regarded as hypothesis-generating, pending further study. [source] Cardiological diagnostic work-up in stroke patients , a comprehensive study of test results and therapeutic implicationsEUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2009B. Schaer Background and purpose:, In some Western countries, many stroke patients undergo routine tests including ECG, echocardiography, carotid ultrasound and Holter monitoring, even though they have been shown to express limited value in unselected patients. Comprehensive data on yield of tests, especially on consequences taken from positive test results, are scanty. Methods:, Consecutive stroke patients with evidence of ischaemic lesions by imaging techniques were included. Aetiology was determined using TOAST-classifications. Rates of positive test results and their impact on drug therapy, especially anticoagulation were evaluated. Results:, Two hundred and forty-one consecutive patients, age 69 ± 13 years were included. Positive test results were documented in 19% with 12-lead ECG, 24% with carotid ultrasound, 24% with echocardiography and never with Holter monitoring. Overall, in 41% positive test results were present. Apart from echocardiography (37%), a change of therapy resulted in 51,56% of patients with a positive test result. Conclusions:, Even though 12-lead ECG, carotid ultrasound and echocardiography only had relatively low incidences of positive findings, their impact on management in case of positive test results was quite high. Nevertheless, future studies to select patients more appropriately are needed. In contrast, Holter monitoring had no impact and should not be used in routine evaluation of stroke patients. [source] Brain Apparent Water Diffusion Coefficient Magnetic Resonance Image During a Prolonged Visual AuraHEADACHE, Issue 6 2010Robert Belvís MD (Headache 2010;50:1045-1049) Background., Reversible changes in brain magnetic resonance imaging (MRI) weighted in diffusion-weighted images (DWI) and apparent water diffusion coefficient (ADC) maps have been reported in acute stroke, epilepsy, eclampsia, and hypoglycemia, but they are contradictory regarding to migraine aura. Objective., A 41-year-old woman with known basilar migraine for 5 years consulted about a persistent visual aura (visual snow phenomenon) plus bilateral paresthesias in the extremities for 4 days. The headache was treated with success with 10 mg of wafer rizatriptan and 600 mg of ibuprophen. Methods., The neurologic and ophthalmologic examination were normal. An urgent brain MRI detected no lesions in T1, T2, fluid-attenuated inversion recovery, and DWI, but an abnormal signal appeared in the left occipital lobe in ADC and (r)ADC maps. The brain MRI angiography, carotid ultrasound study, transesophageal echocardiography, 24-hour cardiac Holter monitoring, and thrombophilia study were normal. Results., A new brain MRI 8 days after did not show any previous lesion in the same sequences. Conclusions., We present a patient with migraine and transitory abnormal signals in the ADC map of an occipital region during persistent visual aura. The clinical-radiological relationship is congruent. Some similar cases have showed these MRI signals during the aura, suggesting cytotoxic edema, without ischemic lesions in the MRI controls. Theses ADC images probably appear in complex auras. [source] Presence and Duration of Atrial Fibrillation Detected by Continuous Monitoring: Crucial Implications for the Risk of Thromboembolic EventsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2009GIOVANNI L. BOTTO M.D. Introduction: Asymptomatic atrial fibrillation (AF) can expose patients to the risk of stroke. The primary objective of this study was to assess the incidence of thromboembolic events in relationship with CHADS2 (congestive heart failure, hypertension, age ,75 years, diabetes mellitus, and prior stroke, or transient ischemic attack) score and AF presence/duration. The secondary objective was to compare intermittent versus continuous monitoring strategies. Methods and Results: Data from patients with an implanted pacemaker and a history of AF were analyzed. Thromboembolic risk was quantified through CHADS2 score. Three AF groups were considered: patients with <5-minutes AF on 1 day (AF-free); patients with >5-minutes AF on 1 day but <24 hours (AF-5 minutes); patients with AF episodes >24 hours (AF-24 hours). Monitoring strategies involving 24-hour Holter, 1-week Holter, and 30-day Holter were simulated. Data from 568 patients continuously monitored for 1 year were analyzed: 171 (30%) had CHADS2 score = 0; 269 (47%) had CHADS2 score = 1; 111 (20%) had CHADS2 score = 2; and 17 (3%) had CHADS2 score , 3. During follow-up, 14 patients (2.5%) had an ischemic thromboembolic event. AF-24 hours patients numbered 223 (39.2%); AF-5 minutes, 179 (31.5%); and AF-free, 29.2%. By combining AF presence/duration with CHADS2 score, two subpopulations with markedly different risks of events (0.8% vs 5%, P = 0.035) were identified, the former corresponding to AF-free with CHADS2,2, or AF-5 minutes with CHADS2,1, or AF-24 hours with CHADS2= 0. The mean sensitivity in detecting an AF episode lasting >5 minutes was 44.4%, 50.4%, and 65.1% for 24-hour Holter, 1-week Holter, and 1-month Holter monitoring, respectively. Conclusion: In patients with recurrent AF episodes, risk stratification for thromboembolic events can be improved by combining CHADS2 score with AF presence/duration. [source] Long-Term Incidence of Malignant Ventricular Arrhythmia and Shock Therapy in Patients with Primary Defibrillator Implantation Does Not Differ from Event Rates in Patients Treated for Survived Cardiac ArrestJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2005ULRICH BACKENKÖHLER M.D. Introduction: Recent trials have demonstrated benefit of prophylactic defibrillator (ICD) implantation compared to conventional treatment in high-risk patients. However, many patients have rare or no sustained arrhythmias following implantation. Our study addresses the question, whether patients with prophylactic defibrillator implantation have a lower risk for life-threatening ventricular tachycardia (VT) or ventricular fibrillation (VF) compared to sudden cardiac death (SCD) survivors. Methods and Results: Over 7 years we enrolled 245 patients. Occurrence of spontaneous sustained VT/VF resulting in adequate ICD treatment was the endpoint. Incidence, type, and treatment of sustained arrhythmia in 43 previously asymptomatic ICD recipients (group B) were compared to data of 202 survivors of imminent SCD (group A). All patients had severely impaired left ventricular ejection fraction (<45%). Group B patients had long runs (>6 cycles, <30 s) of VT during Holter monitoring and inducible sustained arrhythmia. Incidence of rapid VT and VF (cycle length <240 ms/heart rate >250 bpm) after 4 years (35% in both groups, P = ns) and adequate defibrillator therapies (57% vs 55%, P = ns) were similar in both groups after univariate and multivariate analysis. Cumulative mortality tended to be lower in group B compared to group A, but the difference was not statistically significant. Conclusion: During long-term follow-up, incidence of sustained rapid ventricular arrhythmia in prophylactically treated patients is as high as that of SCD survivors. Benefit from defibrillator implantation for primary prevention (group B) appears to be comparable to that for survived cardiac arrest (group A). [source] Relationship Between Heart Rate Turbulence and Heart Rate, Heart Rate Variability, and Number of Ventricular Premature Beats in Coronary PatientsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2004IWONA CYGANKIEWICZ M.D., Ph.D. Introduction: Heart rate variability (HRV) illustrates regulation of the heart by the autonomic nervous system whereas heart rate turbulence (HRT) is believed to reflect baroreflex sensitivity. The aim of this study was to determine the association between HRT and HRV parameters and the relationship between HRT parameters and heart rate and number of ventricular premature beats (VPBs) used to calculate HRT parameters. Methods and Results: In 146 patients (117 males and 29 females; mean age 62 years) with coronary artery disease, a 24-hour ECG Holter monitoring was performed to calculate mean heart rate (RR interval), number of VPBs, time- and frequency-domain HRV parameters and two HRT parameters: turbulence onset (TO) and turbulence slope (TS). Univariate and multivariate regression analyses were performed to evaluate the association between tested parameters. Significant correlation between TS and mean RR interval was observed (r = 0.42; p < 0.001), while no association for TO vs. RR interval was found. TS values were significantly higher in patients with less than 10 VPBs/24 hours than in patients with more frequent VPBs. Significant associations between HRT and HRV parameters were found with TS showing stronger correlation with HRV parameters than TO (r value ranging from 0.35 to 0.62 for TS vs. ,0.16 to ,0.38 for TO). Conclusion: HRT parameters correlate strongly with HRV parameters indicating that HRT should be considered as a reflection of both baroreceptors response and overall autonomic tone. Heart rate dependence of turbulence slope indicates the need to adjust this parameter for heart rate. (J Cardiovasc Electrophysiol, Vol. 15, pp. 731-737, July 2004) [source] Circadian Profile of Cardiac Autonomic Nervous Modulation in Healthy Subjects:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2003Differing Effects of Aging, Gender on Heart Rate Variability Introduction: Although heart rate variability (HRV) has been established as a tool to study cardiac autonomic activity, almost no data are available on the circadian patterns of HRV in healthy subjects aged 20 to 70 years. Methods and Results: We investigated 166 healthy volunteers (81 women and 85 men; age 42 ± 15 years, range 20,70) without evidence of cardiac disease. Time-domain HRV parameters were determined from 24-hour Holter monitoring and calculated as hourly mean values and mean 24-hour values. All volunteers were fully mobile, awoke around 7 A.M., and had 6 to 8 hours of sleep. Circadian profiles of vagus-associated HRV parameters revealed a marked day-night pattern, with a peak at nighttime and a plateau at daytime. The characteristic nocturnal peak and the day-night amplitude diminished with aging by decade. Estimates of overall HRV (geometric triangular index [TI], SD of NN intervals [SDNN]) and long-term components of HRV (SD of the averages of NN intervals for all 5-min segments [SDANN]) were low at nighttime and increased in the morning hours. There was a significant decline of 24-hour values of all HRV parameters (P < 0.001) and a strong negative correlation (P < 0.001) with increasing age. Mean 24-hour RR interval (P < 0.001), SDNN, mean SD of NN intervals for all 5-minute intervals (SDNNi), and SDANN (all P < 0.01) were significantly higher in men. Younger men also exhibited significantly higher values for vagus-associated parameters (root mean square successive difference [rMSSD], P < 0.05; SDNNi, P < 0.01); however, gender differences diminished with increasing age. Conclusion: Normal aging is associated with a constant decline of cardiac vagal modulation due to a significant decrease of nocturnal parasympathetic activity. The significant gender-related difference of HRV decreases with aging. These findings emphasize the need to determine age-, gender-, and nycthemeral-dependent normal ranges for HRV assessment. (J Cardiovasc Electrophysiol, Vol. 14, pp. 791-799, August 2003) [source] Supraventricular Arrhythmias in Children and Young Adults with Implantable Cardioverter DefibrillatorsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2001BARRY A. LOVE M.D. SVT in Pediatric ICD Recipients.Introduction: Rapidly conducted supraventricular tachycardias (SVTs) can lead to inappropriate device therapy in implantable cardioverter defibrillator (ICD) patients. We sought to determine the incidence of SVTs and the occurrence of inappropriate ICD therapy due to SVT in a pediatric and young adult population. Methods and Results: We undertook a retrospective review of clinical course, Holter monitoring, and ICD interrogations of patients receiving ICD follow-up at our institution between March 1992 and December 1999. Of 81 new ICD implantations, 54 eligible patients (median age 16.5 years, range 1 to 48) were identified. Implantation indications included syncope and/or spontaneous/inducible ventricular arrhythmia with congenital heart disease (30), long QT syndrome (9), structurally normal heart (ventricular tachycardia/ventricular fibrillation [VT/VF]) (7), and cardiomyopathies (7). Sixteen patients (30%) received a dual-chamber ICD. SVT was recognized in 16 patients, with 12 of 16 having inducible or spontaneous atrial tachycardias. Eighteen patients (33%) received , 1 appropriate shock(s) for VT/VF; 8 patients (15%) received inappropriate therapy for SVT. Therapies were altered after an inappropriate shock by increasing the detection time or rate and/or increasing beta-blocker dosage. No single-chamber ICD was initially programmed with detection enhancements, such as sudden onset, rate stability, or QRS discriminators. Only one dual-chamber defibrillator was programmed with an atrial discrimination algorithm. Appropriate ICD therapy was not withheld due to detection parameters or SVT discrimination programming. Conclusion: SVT in children and young adults with ICDs is common. Inappropriate shocks due to SVT can be curtailed even without dual-chamber devices or specific SVT discrimination algorithms. [source] Incidence of post-anaesthetic arrhythmias in dogsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 3 2005K. Buhl Objectives: To assess the use of Holter monitoring for evaluating the incidence of post-anaesthetic cardiac arrhythmias and associated anaesthetic risk for two different anaesthetic protocols. Methods: Patients undergoing orthopaedic surgery were randomly divided into two groups with different anaesthetic regimens (group A, isoflurane n=30; group B, propofol n=30). Two 24-hour Holter recordings were performed for each patient: the first directly following anaesthesia and the second, as a comparison, on the fifth postoperative day. Results: Although all dogs were healthy on pre-anaesthetic cardiac evaluation, 56 dogs showed arrhythmias in the two 24-hour (Holter) electrocardiograms performed. However, the number of arrhythmias recorded was low in most cases (less than 10 supraventricular extrasystoles and less than 100 ventricular extrasystoles). One patient in group A showed 94 supraventricular extrasystoles during the second monitoring period. Three patients in each group developed more than 100 ventricular extrasystoles during both Holter recordings. There were no statistically significant differences between the two anaesthetic regimens or between the two recordings in both groups. Clinical Significance: The two anaesthetic protocols investigated in this study did not induce an increased incidence of severe arrhythmias in healthy dogs in the post-anaesthetic phase. [source] Catheter Ablation for Paroxysmal Atrial Fibrillation: A Randomized Comparison between Multielectrode Catheter and Point-by-Point AblationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2010ALAN BULAVA M.D., Ph.D. Introduction:,Catheter ablation for paroxysmal atrial fibrillation is widely used for patients with drug-refractory paroxysms of arrhythmia. Recently, novel technologies have been introduced to the market that aim to simplify and shorten the procedure. Aim:,To compare the clinical outcome of pulmonary vein (PV) isolation using a multipolar circular ablation catheter (PVAC group), with point-by-point PV isolation using an irrigated-tip ablation catheter and the CARTO mapping system (CARTO group; CARTO, Biosense Webster, Diamond Bar, CA, USA). Methods:,Patients with documented PAF were randomized to undergo PV isolation using PVAC or CARTO. Atrial fibrillation (AF) recurrences were documented by serial 7-day Holter monitoring. Results:,One hundred and two patients (mean age 58 ± 11 years, 68 men) were included in the study. The patients had comparable baseline clinical characteristics, including left atrial dimensions and left ventricular ejection fraction, in both study arms (PVAC: n = 51 and CARTO: n = 51). Total procedural and fluoroscopic times were significantly shorter in the PVAC group (107 ± 31 minutes vs 208 ± 46 minutes, P < 0.0001 and 16 ± 5 minutes vs 28 ± 8 minutes, P < 0.0001, respectively). The AF recurrence was documented in 23% and 29% of patients in the PVAC and CARTO groups, respectively (P = 0.8), during the mean follow-up of 200 ± 13 days. No serious complications were noted in both study groups. Conclusions:,Clinical success rates of PV isolation are similar when using multipolar circular PV ablation catheter and point-by-point ablation with a three-dimensional (3D) navigation system in patients with PAF, and results in shorter procedural and fluoroscopic times with a comparable safety profile. (PACE 2010; 33:1039,1046) [source] Heart Rate Turbulence Impairment and Ventricular Arrhythmias in Patients with Systemic SclerosisPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2010PIOTR BIENIAS M.D., Ph.D. Background:,Arrhythmias, conduction disturbances, and cardiac autonomic nervous system dysfunction are the most frequent cardiovascular complications in systemic sclerosis (scleroderma). The aim of the study was to assess heart rate turbulence (HRT) in systemic sclerosis patients and to identify the relationship between HRT and occurrence of arrhythmias. Methods:,Forty-five patients with scleroderma (aged 54.6 ± 14.7 years) and 30 healthy sex- and age-matched subjects were examined. In addition to routine studies, 24-hour Holter monitoring with assessment of HRT was performed. Results:,As compared to controls, HRT was significantly impaired in systemic sclerosis patients. Abnormal HRT defined as turbulence onset (TO) ,0.0% and/or turbulence slope (TS) ,2.5 ms/RR (ms/RR interval) was found in 19 (42%) scleroderma patients and in no members of the control group. Serious ventricular arrhythmias Lown class IV (VA-LownIV), for example, couplets and/or nonsustained ventricular tachycardias, were observed in 16 (36%) scleroderma patients. The median value of TS was significantly lower in systemic sclerosis patients with VA-LownIV than in patients without VA-LownIV (3.68 vs 7.00 ms/RR, P = 0.02). The area under curve of ROC analysis for prediction of VA-LownIV was 0.72 (95% confidence interval [CI] 0.56,0.87) and revealed that TS <9.0 ms/RR was associated with VA-Lown IV occurrence, with sensitivity of 93.7% and specificity of 44.8%. Univariate and multivariate analyses confirmed that lower values of TS were associated with VA-LownIV occurrence (odds ratio 1.52, 95% CI 1.09,2.12, P = 0.01). Conclusions:,Patients with systemic sclerosis are characterized by significant HRT impairment. Assessment of HRT and especially TS is useful in the identification of patients at risk for ventricular arrhythmias. (PACE 2010; 920,928) [source] Heart Rate Variability in Arrhythmogenic Right Ventricular Cardiomyopathy Correlation with Clinical and Prognostic FeaturesPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2002ANTONIO FRANCO FOLINO FOLINO, A.F., et al.: Heart Rate Variability in Arrhythmogenic Right Ventricular Cardiomyopathy Correlation with Clinical and Prognostic Features. The identification of subjects with arrhythmogenic right ventricular cardiomyopathy (ARVC) at higher risk for sudden death is an unresolved issue. An influence of the autonomic activity on the genesis of ventricular arrhythmias was postulated. Heart rate variability (HRV) analysis provides a useful method to measure autonomic activity, and is a predictor of increased risk of death after myocardial infarction. For these reasons, the aim of the study was to evaluate HRV and its correlations with ventricular arrhythmias, heart function, and prognostic outcome in patients with ARVC. The study included 46 patients with ARVC who were not taking antiarrhythmic medications. The diagnosis was made by ECG, echocardiography, angiography, and endomyocardial biopsy. Exercise stress test and Holter monitoring were obtained in all patients. Time-domain analysis of HRV was expressed as the standard deviation of all normal to normal NN intervals (SDNN) detected during 24-hour Holter monitoring. Thirty healthy subjects represented a control group for HRV analysis. The mean follow-up was 10.8 ± 1.86 years. SDNN was reduced in patients with ARVC in comparison with the control group (151 ± 36 vs 176 ± 34, P = 0.00042). Moreover, there was a significant correlation of this index with the age of the patients (r =,0.59, P < 0.001), with the left (r = 0.44, P = 0.002) and right (r = 0.47, P = 0.001) ventricle ejection fraction, with the right ventricular end diastolic volume (r =,0.62, P < 0.001), and with the ventricular arrhythmias, detected during the same Holter record used for HRV analysis (patients with isolated ventricular ectopic beats < 1,000/24 hours, 184 ± 34; patients with isolated ventricular ectopic beats > 1,000/24 hours and/or couplets, 156 ± 25; patients with repetitive ventricular ectopic beats (,3) and/or ventricular tachycardia, 129 ± 25; P < 0.001). During follow-up two patients showed a transient but significant reduction of SDNN and a concomitant increase of the arrhythmic events. In eight patients an episode of sustained ventricular tachycardia occurred, but the mean SDNN of this subgroup did not differ from the mean value of the remaining patients (152 ± 15 vs 150 ± 39; P = NS). Only one subject died after heart transplantation during follow-up (case censored). Time-domain analysis of HRV seems to be a useful method to assess the autonomic influences in ARVC. A reduction of vagal influences correlates with the extent of the disease. The significant correlation between SDNN and ventricular arrhythmias confirmed the influences of autonomic activity in the modulation of the electrical instability in ARVC patients. However, SDNN was not predictive of spontaneous episodes of sustained ventricular tachycardia. [source] Criteria for Pacemaker Explant in Patients Without a Precise Indication for Pacemaker ImplantationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2002MARTINO MARTINELLI MARTINELLI, M., et al.: Criteria for Pacemaker Explant in Patients Without a Precise Indication for Pacemaker Implantation. Unnecessary pacemaker implantation may cause significant social and psychological consequences, the inconvenience of periodic office visits, and the expense of pulse generator replacement. Establishing adequate criteria for explanting pacemakers is crucial and has not yet been described. This study presents the results of a study protocol for explanting the pacemaker in patients without a clear indication for pacemaker implantation. Seventy pacemaker users without a clear reason for the implantation were included in the study conducted from August 1986 to November 1998 and were prospectively followed. The investigation consisted of clinical and neurological evaluations, echocardiogram, exercise testing, and tilt table testing. When these tests were negative, the pulse generator energy and stimulation rates were reprogrammed to the lowest values. Periodic Holter monitoring was conducted during follow-up. When asymptomatic for 1 year, patients underwent an electrophysiological evaluation of sinus and atrioventricular junction function and ventricular vulnerability. When the electrophysiological study was negative, pacemaker explantation was performed. Of the 70 patients, 35 had their pacemaker explanted; 3 were excluded due to a positive tilt table test and electrophysiological study, and 3 are waiting for pacemaker explantation. Mean follow-up after pacemaker explantation was 30.3 months, and all patients remained asymptomatic, except for one patient who died of a noncardiac cause. Critical analysis of pacemaker users without a well-established indication is justified because it may allow pacemaker explant in a significant proportion of these patients, and it may bring considerable social, economic, and psychological benefits. [source] Contribution of a Pacemaker Bradycardia Detection Algorithm in the Study of Patients with Carotid Sinus SyndromePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2001PIERRE GRAUX GRAUX, P., et al.: Contribution of a Pacemaker Bradycardia Detection Algorithm in the Study of Patients with Carotid Sinus Syndrome. While carotid sinus syndrome (CSS) is often suspected as a cause of syncope in the elderly, whether it represents an indication for cardiac pacing may remain uncertain. Bradycardia algorithms included in pacemakers are now able to establish a precise relationship between spontaneous asystole and occurrence of symptoms and strengthen the indication for permanent pacing. This study included seven men and three women (70.5 ± 7.3 years of age) who, over an average period of 54.1 ± 17 months, had suffered from syncope (12.6 episodes/patient) and presyncope (11.2 episodes/patient) attributed to pure cardioinhibition (2 patients) or mixed CSS (8 patients). Other sources of symptoms were excluded by thorough clinical evaluations, including Holter monitoring, echocardiography, and electrophysiological testing. All patients received a CHORUS 6234 pacemaker, the memory of which includes a dedicated bradycardia detection algorithm capable of storing atrial and ventricular chains, and date and time of the last ten pauses and/or bradycardic events. After a initial period of 14.7 ± 8 months, during which symptoms were suppressed, the bradycardia algorithm was activated. From then on, a cumulative increase in the number of patients presenting with diurnal pauses was measured (1 month, n = 0; 3 months, n = 6; 9 months, n = 7; 2 years, n = 8). Fourteen episodes of diurnal asystole were recorded. The mean duration of the longest episodes of spontaneous ventricular standstill was 6,319 ± 1,615 ms and was due to sinoatrial block (n = 7), atrioventricular block (n = 5), and a combination of both (n = 2). In conclusion, activation of the CHORUS bradycardia algorithm allowed confirmation of the appropriateness of permanent pacing in a majority of patients suffering from CSS. [source] Microvolt T-Wave Alternans during Holter Monitoring in Children and AdolescentsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010Leonid Makarov M.D. Background: Time-domain microvolt T-wave alternans (TWA) has been described as a noninvasive marker of sudden cardiac death in adults. The incidence of TWA in pediatric populations has not been defined well. The aim of the study was to determine peculiarities of TWA in children. Methods: We examined 68 healthy patients,newborns (20) and children in age group of 7,17 years (48),and 85 pediatric patients: ventricular premature beats,65; dilated cardiomyopathy (DCMP),2; long QT syndrome (LQTS),10; Brugada syndrome (BrS),5, catecholaminergic ventricular tachycardia (CVT),3. All underwent Holter monitoring (HM) with definition of the peak value of TWA by modified moving average method. Results: In healthy newborns, TWA was 32 ± 8 (12,55) ,V (HR 123,156 bmp). In healthy children (7,17 years) it was 30 ± 11 (10,l 55) ,V, (HR 64,132 bmp) without any differences between boys and girls. In all group of patients, TWA were significantly higher (P < 0.05) than in healthy. Circadian peak of TWA was found (90%) in a second part of day and at sleep (8%). Among them 60% (LQTS, BrS, and DCPM) had TWA > 55 ,V. Conclusion: Time-domain TWA during HM in children was independent of age, gender, and heart rate. In 94% healthy children, values of TWA do not exceed 55 ,V but 20,50% children with cardiac pathology had TWA more than 55 ,V. Night circadian type of TWA in diseases with risk of life-threatening arrhythmias associated with TWA was more than 55 ,V. Ann Noninvasive Electrocardiol 2010;15(2):138,144 [source] Evaluation of the Relationship between Atrial Septal Aneurysm and Cardiac Arrhythmias via P-Wave Dispersion and Signal-Averaged P-Wave DurationANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010Onur Sinan Deveci M.D. Objective: The aim of the study was to investigate the relationship between atrial septal aneurysms (ASAs) and cardiac arrhythmias via signal-averaged P-wave duration (SAPWD) and P-wave dispersion (Pd). Methods: Sixty-six patients with ASA served as the study group (group 1; 28 men and 38 women; mean age, 34 ± 10 years) and 62 healthy volunteers served as the control group (group 2; 29 men and 33 women; mean age, 31 ± 8 years) in the current study. ASAs were diagnosed by transthoracic echocardiography based on the criteria of a minimal aneurysmal base of ,15 mm; and an excursion of ,10 mm. All subjects were evaluated by 24-hour Holter monitoring, 12 lead body surface electrocardiogram for P-wave analysis, and signal-averaged electrocardiogram for P-wave duration (PWD). Results: There was no significant difference between the study and control groups in terms of age, gender, left atrium diameter, and left ventricular ejection fraction. Supraventricular arrhythmias (SVAs) were detected in 29 patients with ASA (43.9%) and 5 controls (8.1%; P < 0.001). The mean Pd in patients with ASA was significantly longer compared to the control group (14.1 ± 8 ms vs 7.0 ± 2.9 ms; P < 0.001). Similarly, the mean SAPWD in group 1 was significantly longer compared to group 2 (127.4 ± 17.6 ms vs 99.8 ± 12.3 ms; P < 0.001). Conclusion: Prolonged SAPWD and Pd were determined to indicate electrical disturbances in the atrial myocardium, and predict the increase in the prevalence of SVA in patients with ASA. Ann Noninvasive Electrocardiol 2010;15(2):157,164 [source] Electrocardiographic Evaluation in Patients with Systemic Scleroderma and without Clinically Evident Heart DiseaseANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2009Anna Bie, Ph.D., ous-Wilk M.D. Background: In patients with systemic scleroderma (SSc), clinically evident cardiac involvement is recognized to be a poor prognostic factor. The aim of the study was to evaluate electrocardiographic changes, parameters of heart rate variability (HRV), and heart rate turbulence (HRT) in patients with SSc without evident symptoms of heart disease. Methods: A group of 27 patients with SSc were subjected to standard electrocardiography (ECG) examination and 24-hour Holter monitoring. Analysis of HRV in time and frequency domains, HRT, and echocardiography were also performed. Results: Holter monitoring revealed a larger number of premature supraventricular contractions (PSVCs), as well as premature ventricular contractions (PVCs) in the patients with systemic scleroderma, as compared with the control group. Moreover, the SSc patients showed decreased parameters of time and frequency domains, as referred to the controls, especially during night hours. In four patients, abnormal HRT values were present. On echocardiography, only slight changes were found, however in five patients left ventricle diastolic dysfunction was diagnosed. Conclusions: The noninvasive electrocardiographic methods seems to be useful for detecting early heart involvement in course of SSc and could be recommended for routine used in clinical practice. Significance of HRT analysis in patients with SSc needs further elucidation. [source] Automated QT Analysis That Learns from Cardiologist AnnotationsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2009Iain Guy David Strachan Ph.D. Background: Reliable, automated QT analysis would allow the use of all the ECG data recorded during continuous Holter monitoring, rather than just intermittent 10-second ECGs. Methods: BioQT is an automated ECG analysis system based on a Hidden Markov Model, which is trained to segment ECG signals using a database of thousands of annotated waveforms. Each sample of the ECG signal is encoded by its wavelet transform coefficients. BioQT also produces a confidence measure which can be used to identify unreliable segmentations. The automatic generation of templates based on shape descriptors allows an entire 24 hours of QT data to be rapidly reviewed by a human expert, after which the template annotations can automatically be applied to all beats in the recording. Results: The BioQT software has been used to show that drug-related perturbation of the T wave is greater in subjects receiving sotalol than in those receiving moxifloxacin. Chronological dissociation of T-wave morphology changes from the QT prolonging effect of the drug was observed with sotalol. In a definitive QT study, the percentage increase of standard deviation of QTc for the standard manual method with respect to that obtained with BioQT analysis was shown to be 44% and 30% for the placebo and moxifloxacin treatments, respectively. Conclusions: BioQT provides fully automated analysis, with confidence values for self-checking, on very large data sets such as Holter recordings. Automatic templating and expert reannotation of a small number of templates lead to a reduction in the sample size requirements for definitive QT studies. [source] Circadian Variation in QT Dispersion Determined from a 12-Lead Holter Recording: A Methodological Study of an Age- and Sex-Stratified Group of Healthy SubjectsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2007Stig Hansen M.D. Background: QT dispersion is considered to reflect inhomogeneity of myocardial repolarization. Method: The circadian variation of QT interval dispersion was examined in 95 healthy subjects using 24-hour Holter monitoring. Three different methods of lead selection were applied: all 12 leads (QTdisp 12), only precordial leads (QTdisp 6), and the pair of leads selected at 3 a.m. in which the longest and shortest QT intervals were found in each individual subject (QTdisp 2). Results: A preliminary methodological study including measurements from every minute in 10 subjects revealed no significant circadian variation using mean values of QTdisp 12, QTdisp 6, or QTdisp 2 obtained every hour, every 2, or every 4 hours, except in QTdisp 6, which demonstrated a significant circadian variation (P < 0.01) in 1-hour measurements. Analysis of all 95 subjects using measurements obtained every 4 hours revealed a significant circadian variation in QTdisp 12 and QTdisp 6 (P < 0.0001), whereas no circadian variation was seen in QTdisp 2. A subdivision into 10-year age groups revealed that subjects at age >50 years had a significant circadian variation in QTdisp 12 and QTdisp 6, but not in QTdisp 2. Only in males a significant circadian variation was seen in QTdisp 12 (P < 0.0001), whereas QTdisp 6 demonstrated a circadian variation both in females (P < 0.001) and in males (P < 0.0001). Conclusions: Selection of leads is of crucial importance for repetitive measurements of QT dispersion. Circadian variation was detected in subjects over 50 years of age, when all 12 or only the 6 precordial leads were taken into account. [source] Pacemaker Memory Data Compared to Twenty-Four-Hour Holter Monitoring in Patients with VVI Pacemakers and Chronic Atrial FibrillationANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2005Michal Chudzik M.D., Ph.D. Background: In light of the results from the AFFIRM trial, the "rate control" strategy has become an accepted treatment modality for patients with atrial fibrillation (AF). Establishing effective rate control requires long-term monitoring of the heart rate. The aim of the study was to compare the heart rate and rhythm monitoring capabilities of the pacemaker memory data (PMD) algorithm and traditional twenty-four-hour Holter monitoring. Methods: The study included 55 patients with chronic AF and a permanent VVI pacemaker. The mean and maximum heart rate as well as the percentage of sensed and paced events obtained from the twenty-four-hour Holter were compared with the results retrieved from PMD, started simultaneously. The study was performed over two consecutive days with pacemakers programmed in VVI 40 and 80 bpm mode. Results: Data retrieved from PMD regarding percentage of sensed and paced episodes as well as mean heart rate strongly correlated with data obtained from twenty-four-hour Holter monitoring. The maximum heart rate reported by PMD was significantly higher than that found in the Holter. Conclusions: PMD provides accurate information regarding long-term monitoring of heart rate in patients with AF who have an implanted permanent pacemaker and thus may facilitate optimized drug therapy to achieve rate control of AF. [source] White Blood Cell Count and the Occurrence of Silent Ischemia after Myocardial InfarctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2003gorzata Kurpesa Background: Inflammation plays a role in the pathogenesis of atherosclerosis. Attempts are made to use markers of inflammation as prognostic factors in coronary artery disease and acute coronary syndromes. The correlation between inflammation and silent postinfarction ischemia is unknown. Methods: The study population consists of 104 asymptomatic patients who had uncomplicated Q-wave myocardial infarction within 6 months prior to the enrollment. After the white blood cell (WBC) count was assessed, the population was divided into two groups: group I comprising 48 patients with WBC , 7.0 × 103/,l and group II comprising 56 patients with WBC > 7.0 × 103/,l. Twenty-four-hour Holter monitoring was performed to detect the presence of silent ischemia. Results: Eighty-eight silent ischemic episodes were recorded. Ischemia on Holter monitoring was detected in 47 patients (84%) from group II and in five patients (9%) in group I (P < 0.01). We have found a significant positive correlation between WBC count and the number of ischemic episodes (r = 0.25), their maximal amplitude (r = 0.39), duration (r = 0.34), and total ischemic burden (r = 0.36). In multivariate analysis leucocytosis proved to be the only parameter independently correlated with the presence of silent ischemia. Conclusion: Postinfarction asymptomatic patients with increased WBC count are more likely to have residual ischemia. [source] Heart Rate Variability by Triangular Index in Infants Exposed Prenatally to CocaineANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2002M.B.A., Sudhir Ken Mehta M.D. Background: In adults, heart rate variability triangular index (HRVi) is a highly reproducible measure of heart rate variability (HRV), which makes it more suitable for use in longitudinal studies. Although normative data have been published for newborns, studies in infants with pathological conditions are lacking. Methods: From 1997 to 2000, within the first 4 days of life, we prospectively evaluated HRVi in cocaine-exposed asymptomatic newborns (N = 97) by Holter monitoring. Their data were compared with infants from two control groups (one with no in utero drug exposure, N = 102; the other with exposure to alcohol, nicotine, or marijuana but no cocaine, N = 111). Results: In assessing concordance between and within operators for HRVi, the intraclass correlations were 0.983 (95% Cl: 0.958, 0.994) and 0.997 (95% Cl: 0.984, 0.999), respectively. Infants with in utero cocaine exposure had significantly (P < 0.0001) lower HRVi than those exposed to other drugs and to no drugs in utero. If abnormal HRVi is defined as < fifth percentile for the no drug exposed group (HRVi < 8), 10% of the cocaine-exposed newborns, in contrast to 2% in each of the control groups (P = 0.003) had abnormal values. Conclusion: HRVi is a reliable measure to study heart rate variability in newborns. Asymptomatic infants with in utero cocaine exposure have lower HRVi. Our study supports the clinical use of an abnormal HRVi as a value < 8 for newborn infants. A.N.E. 2002;7(4):374,378 [source] Evaluation of Patients with Palpitations: Cardiac Event Recorder Versus 48-hour Holter MonitoringANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2000Ewa Makowska M.D. Objectives: (1) To compare a diagnostic yield of cardiac event recorders with that of 48-hour Holler monitoring, (2) to determine the etiologies of palpitations, and (3) to assess an optimal duration of using an event recorder by a patient. Background: Palpitation is a common symptom which accounts for 16% of total complaints reported by patients in general medical settings. An ambulatory Holter ECG monitoring or an event recorder can be used to establish the cause of palpitations. Methods: (1)The study group consisted of 33 consecutive patients (24 females, 9 males, mean age 50 ± 32 years) with undiagnosed attacks of palpitations, occurring at least once per month. Each patient was randomly allocated to use either an event monitor or 48-hour Holler monitoring. The patient kept the event monitor for 4 weeks. After the first monitor was returned, the patient was given the other device. Results: Holter monitoring determined the etiology of palpitations in 11 (33%) patients, and the event recorder in 21 (64%) patients (P = 0.0138). In the whole study group, the etiology of palpitations was disclosed in 23 (70%) patients. The diagnosis was possible using Holler ECG monitoring in only 2 (9%) patients, whereas the event recorder revealed the underlying mechanism of palpitations in 12 (52%) patients (P = 0.0007). In nine (39%) patients both methods were able to disclose the eliology of palpitations. The findings of 117 recordings obtained using an event recorder during palpitations were atrial fibrillation in 10 (9%), narrow QRS tachycardia in 4 (3%), frequent supraventricular eclopy in 17 (15%), frequent ventricular eclopy in 6 (5%), and episodes of palpitations sinus rhythm were recorded in the remaining 80 (68%). Of patients who experienced episodes of palpitations while using an event recorder, the earliest recording was obtained on the first day of the study, and the latest on the 18 day of using the event recorder. Conclusions: (1) The cardiac event recorders yield more diagnoses than 48-hour Holter monitoring in patients with palpitations occurring at least once per month, (2) in this group of patients the event recorder provided a diagnostic ECG recording during the first 18 days of using the device, and (3) in the majority (57%) of patients a normal sinus rhythm was recorded during episodes of palpitations. A.N.E. 2000;5(4):315,321 [source] The Utility of Holter Monitoring Compared to Loop Recorders in the Evaluation of Syncope and PresyncopeANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2000Andrew D. Krahn M.D. Background: Holter monitoring is frequently used to assess patients with syncope, but rarely provides a diagnosis. Newer loop recorders provide the opportunity for prolonged electrocardiographic monitoring to enhance diagnostic yield. Methods: The results of 232 Holter monitors and 81 loop recordings performed for the investigation of syncope or presyncope were reviewed for indication, patient demographics, and presence and type of symptoms and/or arrhythmias. The results were classified as (1) symptom-arrhythmia correlation, (2) clinically useful information (group 1 plus those excluding arrhythmic syncope, and those demonstrating asymptomatic serious arrhythmias) and (3) unhelpful (asymptomatic and no serious arrhythmias). Results: Loop recorders provided a symptom-arrhythmia correlation in 11.1% of patients compared to only 0.4% in the Holter group (P < 0.0001). Clinically useful information was obtained in 54.3% of loop patients compared to 27.6% in the Holter group (P < 0.0001). Technical problems occurred in 0.4% of the Holter patients and in 3.7% of loop patients (P = 0.05). Classification was difficult in seven patients in the Holter group; two experienced symptoms during sinus rhythm but also had a serious asymptomatic arrhythmia, and five patients had 6,10 beats of asymptomatic ventricular tachycardia at a rate < 160 beats/min. Conclusion: Loop recording was well tolerated and superior to Holter monitoring in providing a symptom-arrhythmia correlation or clinically useful information in patients with syncope and presyncope. An initial approach with a loop-recording device should be employed in these patients. [source] Relationship Between Myocardial Beta-Adrenergic Sensitivity and Heart Rate VariabilityANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2000Philippe Cabrol M.D. Background: In congestive heart failure, despite activation of the sympathetic nervous system, heart rate variability parameters reflecting sympathetic modulation on sinus node are decreased. Our goal was to assess the role of beta-adrenergic sensitivity in the modulation of heart rate variability (HRV) in patients with valvular heart diseases. Methods and results: Ten patients with aortic stenosis, 10 patients with heart failure, and 12 controls were included. Baroreflex sensitivity was calculated by the sequency method. Noradrenaline plasma levels were assayed by HPLC. HRV was studied using 24-hour Holter monitoring. Cardiac beta-adrenergic receptivity was assessed by the chronotropic response to dobutamine. Right auricular samples were obtained for determination of beta-adrenergic receptor density by binding study with [125I]-iodocynaopindolol, and beta 1 and beta 2 densities, measured by competition between 125ICP binding by isoprenaline. In multivariate analysis, the dose of dobutamine that increases basal heart rate for 25 beats/min (ED25) is correlated with a parameter of global HRV: SDNN (r = 0.6, P < 0.001) and with indexes reflecting rather sympathetic modulation of HRV: SDANN (r = 0.62, P < 0.001) or SD (r = 0.47, P < 0.0001). All these relations were independent from mean NN, spontaneous baroreflex sensitivity, and noradrenaline plasma levels. No significant correlation existed between dobutamine ED25 and HRV indexes reflecting parasympathic tone. No relationship existed between HRV and beta-adrenergic receptor-binding characteristics. Conclusion: Cardiac beta-adrenergic sensitivity explored by dobutamine ED25 is an important determinant of HRV independent from mean NN, spontaneous baroreflex sensitivity, and noradrenaline plasma levels. [source] | |||||||||||||||||||||||||