Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Heart Rate Variability Is Decreasing During Paroxysmal Atrial Fibrillation (1999)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of noninvasive electrocardiology 4 (1999), S. 0 
    Details
    ISSN: 1542-474X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The high R-R variability in permanent atrial fibrillation (AF) is stable. Its behavior in paroxysmal AF is unknown. The aim of this study was to examine heart rate variability behavior during paroxysmal AF and its relationship with clinical characteristics by using time-domain indices and scatterplot analysis.〈section xml:id="abs1-2"〉〈title type="main"〉MethodsIn 43 patients, R-R variability was assessed by time-domain indices and graphical measurements of scattering area (SA) on scatterplot for each sample of 150-second ventricular rhythms extracted at the onset, the middle, and before termination of AF episodes recorded on Holter monitoring. Results were compared between the three time periods, and a nested procedure assessed the components of the SA variance.〈section xml:id="abs1-3"〉〈title type="main"〉ResultsIn 110 episodes lasting 89 ± 130 minutes with a mean of 2.5 ± 3 (1–12) per patient, mean R-R interval did not significantly change while time-domain indices and SA significantly decreased between the three time periods (P 〈 0.05 for SD and CV, P 〈 10−2 for rMSSD and pNN50, P 〈 10−4 for SA, ANOVA 1). The magnitude of the decrease in SA was not related to any episode characteristic; in addition, there was no variation from episode to episode within patient (1% of SA variance), and the high variation between patients (70%, P 〈 10−4) was not related to any clinical parameter.〈section xml:id="abs1-4"〉〈title type="main"〉ConclusionsHeart rate variability decreases gradually during paroxysmal AF. This decrease is peculiar to each patient, unrelated to clinical status. A.N.E. 1999; 4(2):144–151
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1542-474X.1999.tb00053.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Abnormalities of Ventricular Repolarization in Mitral Valve Prolapse (2005)
    350 Main Street , Malden , MA 02148 , USA , and 9600 Garsington Road , Oxford OX4 2XG , UK . : Blackwell Publishing, Inc.
    Annals of noninvasive electrocardiology 10 (2005), S. 0 
    Details
    ISSN: 1542-474X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Objectives: Mitral valve prolapse (MVP) is associated with arrhythmias and sudden death. Some studies suggest that abnormalities of the autonomic nervous system (ANS) may contribute to these arrhythmias. In a family investigation with genetic analysis of patients carrying a MVP, we performed a Holter study to define the autonomic profile of MVP. Methods and Results: A 24-hour digitized 3-lead Holter ECG was recorded in 30 patients with MVP and in two control groups, a group of 30 healthy relatives and a group of 31 healthy volunteers. We studied especially heart rate variability (HRV) and QT dynamicity. The slope of the relationship between ventricular repolarization and heart rate was studied separately during day and night. There was no difference in HRV (SDNN, rMSSD) among the three groups. On the contrary, QT interval duration was increased in patients with MVP as compared to healthy relatives (QT end: 409 ± 52 ms vs 372 ± 23 ms, P 〈 0.05; QT apex: 319 ± 42 ms vs 286 ± 23 ms, P 〈 0.01) and to healthy volunteers (QT end: 409 ± 52 ms vs 376 ± 25 ms, P = 0.004; QT apex: 319 ± 42 ms vs 289 ± 23 ms, P 〈 0.01). Nocturnal ventricular repolarization rate dependence was increased in MVP as compared to healthy relatives (0.16 ± 0.06 vs 0.13 ± 0.04, P 〈 0.05) and to healthy volunteers (0.16 ± 0.06 vs 0.11 ± 0.06, P 〈 0.001) whereas the 24-hour and diurnal QT–R-R slope was not disturbed. Conclusion: In MVP, QT is increased and the circadian modulation of QT end/RR slope is disturbed with an increased nocturnal rate dependence. These abnormalities of ventricular repolarization might explain the risk of arrhythmic events in MVP.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1542-474X.2005.00630.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Temporal and Geographical Trends in Indications for Implantation of Cardiac Defibrillators in Europe 1993–1998 (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Pacing and clinical electrophysiology 23 (2000), S. 0 
    Details
    ISSN: 1540-8159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Despite the demonstrated efficacy of implantable cardioverter defibrillators (ICDs) in reducing sudden and total mortality in selected populations, their implantation rates vary greatly between countries. The aim of our study was to analyze temporal and geographical trends in ICD implantations in countries with similar health related expenditure in Western Europe. A total of 2,257 patients from ten European evaluation studies of Medtronic defibrillators and defibrillation electrodes, conducted between 1993 and 1998, representing 12 countries, was included in this analysis. Rates of implantation and clinical characteristics were compared between countries and years of implantation. Rates of implantation differed greatly between Western European countries and did not correlate with indices of health related expenditure (i.e., number of patients per physician and number of patients per hospital bed). However, there was a strong and statistically significant negative correlation between the use of amiodarone and the rates of implantation (r =−0.66, P = 0.02). Temporal trends showed a significant increase in the age of the patients receiving an ICD between 1993 and 1998(57 ± 14 vs 61 ± 12years, mean ± SD, P 〈 0.001). There was also a temporal trend towards an increased incidence of coronary artery disease and a significant decrease in the incidence of cardiomyopathy. There was a temporal increase in implantations in patients with a history of ventricular tachycardia. Despite a general scientific agreement that ICDs are a first line treatment for patients at high risk of sudden cardiac death, their acceptance remains low in several developed countries. This low acceptance may not be entirely related to budget constraint but may also be related to their perceived efficacy by physicians and health authorities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1540-8159.2000.tb00884.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Effects of a Selective Al-Adenosine Receptor Agonist on Heart Rate and Heart Rate Variability During Permanent Atrial Fibrillation (1998)
    Oxford, UK : Blackwell Publishing Ltd
    Pacing and clinical electrophysiology 21 (1998), S. 0 
    Details
    ISSN: 1540-8159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background: Mean heart rate and irregularity of the rate, i.e., heart rate variability (HRV), are two aspects of heart rate during atrial fibrillation (AF). An important goal of AF therapy is to control mean heart rate during exercise; the determinants of HRV during AF remain poorly known although its prognostic value has been established. Objectives: To investigate the effects of a stable, long-acting, selective A1-adenosine receptor agonist, SDZ WAG994, on heart rate during exercise and on HRV. Methods: In a multicenter, double-blind, randomized, placebo-controlled, parallel group study, patients with permanent AF performed a symptom-limited exercise test and underwent 24-hour ECG monitoring on day 1 during treatment with placebo, and on day 2 during treatment with either placebo or 2 mg SDZWAG994 orally. Changes in mean heart rate during exercise and changes in HRV indices between day 1 and day 2 were compared between the two groups. Results: Thirty-two patients (64 ± 8 years; 81% male; 25% in NYHA Class II; 38% with no structural heart disease) were included in the study. During active treatments, heart rate remained unchanged at rest and increased significantly during exercise. A significant daytime increase in short-term HRV indices (DpNN50 = 4.5% P = 0.01; DrMSSD = 6% P = 0.03; DSDNN Index = 6% P = 0.02) occurred during active treatment. Conclusions: Selective A1-adenosine receptor agonism with SDZ/WAG994 limits the increase in mean heart rate during exercise in patients with AF. In addition, this agonist selectively increases short-term HRV indices, suggesting that pNN50, rMSSD, and SDNN reflect vagal influences during AF.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1540-8159.1998.tb01201.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    An Unusual Mode of Initiation of Supraventricular Tachycardia (1997)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of cardiovascular electrophysiology 8 (1997), S. 0 
    Details
    ISSN: 1540-8167
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1540-8167.1997.tb00800.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Characterization of a Long Linear Thermolesion in Rabbit Atria by High Density Mapping (2002)
    Oxford, UK : Blackwell Futura Publishing, Inc.
    Pacing and clinical electrophysiology 25 (2002), S. 0 
    Details
    ISSN: 1540-8159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: PIOT, O., et al.: Characterization of a Long Linear Thermolesion in Rabbit Atria by High Density Mapping. A major problem in radiofrequency ablation is to evaluate if linear atrial lesions are transmural and continuous. Characteristics of the atrial electrograms recorded from these lesions might be useful to determine the completeness of linear atrial lesions. In seven isolated perfused rabbit atria, a long transmural linear lesion was made with a hot needle (perfused with water of 80°C) (width 2 ± 0.2 mm). The lesion extended from the orifice of the superior caval vein to the AV ring. High density mapping (240 electrodes, 7.5 × 7.5 mm) of the right atrium was performed before and after the lesion. Complete bidirectional conduction block was confirmed by pacing close at either side of the lesion. No change in conduction or electrogram characteristics occurred outside the lesion. From the center of the lesion, low amplitude double potentials were recorded. The conduction delay around the lesion and the width of the double potentials showed a high correlation (R2= 0.99) and were both dependent of the site of pacing. From the boundaries of the lesion towards its center, the amplitude and slope of the unipolar electrograms decreased exponentially by 72 ± 5 and 85 ± 3%. From the decay of these electrotonic potentials a space constant (λof 0.79 ± 0.04 mm) could be calculated for the lesion. Unipolar electrograms recorded from a complete and transmural linear atrial lesion are electrotonic in nature. Their characteristics could be used to evaluate the width and depth of the lesion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1460-9592.2002.00167.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...