Document Detail


The effect of internal DC shocks on the atrial fibrillation frequency.
MedLine Citation:
PMID:  18002525     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The objective of this study, was to investigate the effect of internal DC shocks on the atrial fibrillation frequency (AFF). AFF has previously been shown to predict the success and energy requirements in patients undergoing internal cardioversion (IC) of atrial fibrillation (AF). However the possibility that unsuccessful shocks during IC may influence the AFF has not been before studied. Thirty eight patients with AF, suggested for DC cardioversion at the Royal Victoria Hospital in Belfast, were included in our study. Two catheters were positioned in the right atrial appendage (RAA) and the coronary sinus (CS), to deliver a biphasic shock waveform, synchronized with the R wave of the electrocardiogram (ECG) signal. A voltage step-up protocol (50-300 V) was used for patient cardioversion. The ECG was analyzed for a mean of 52,8+/-10.1 seconds (corresponding to segments before and after nonsuccessful shocks). Atrial fibrillatory activity was extracted by means of bandpass filtering and ventricular activity (QRST) cancellation. QRST complexes were cancelled using a recursive least squared (RLS) adaptive filter. FFT was applied to the residual atrial fibrillatory signal. AFF was estimated from the dominant frequency within the 3-12 Hz band of the power spectrum. R-R intervals during the segments were also analyzed. A total of 26 patients were successfully cardioverted, employing 167 shocks (141 nonsuccessful). AFF, computed with 10 s of signal, showed significant reduction (mean 0.3052 +/- 1.1055 Hz, P=0.028) comparing segments immediately before and after shocks, and AFF significantly increases (mean 0.2582 +/- 0.609 Hz, P=0.007) between segments immediately after shocks and those 35 s after. AFF showed distinct behavior according to the energy level of the shocks. In conclusion, intracardiac electric shocks could cause transitory changes in the AFF of patients with atrial fibrillation.
Authors:
J Diaz; N Castro; O Escalona; J McC Anderson; B M Glover; J A Adgey
Related Documents :
7611485 - Predicting the potential gradient field in ventricular fibrillation from shocks deliver...
10455875 - Liposomal delivery of heat-shock protein 72 into the heart prevents endotoxin-induced m...
9533375 - Efficacy of low-energy t wave shocks for induction of ventricular fibrillation in patie...
20328285 - Shock following myocardial infarction: a clinical survey of 140 cases.
19077815 - Ecg manifestations of left atrial flutter.
9768705 - Effects of thrombolytic therapy in acute inferior myocardial infarction with or without...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference     Volume:  2007     ISSN:  1557-170X     ISO Abbreviation:  Conf Proc IEEE Eng Med Biol Soc     Publication Date:  2007  
Date Detail:
Created Date:  2007-11-16     Completed Date:  2008-05-05     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101243413     Medline TA:  Conf Proc IEEE Eng Med Biol Soc     Country:  United States    
Other Details:
Languages:  eng     Pagination:  2591-4     Citation Subset:  IM    
Affiliation:
Universidad Simón Bolívar, Caracas, Venezuela. 03-83260@usb.ve
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Atrial Fibrillation / therapy*
Defibrillators, Implantable*
Electric Countershock / methods*
Humans

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Impact of sampling rate reduction on automatic ECG delineation.
Next Document:  Estimation of the scope of transvenous lead systems in implantable cardioverter defibrillators.