Real Time Frequency Analysis of Signals From Lasso Catheter For Radiofrequency Ablation During Atrial Fibrillation

Real time spectrum analysis of signals obtained through lasso catheter during radiofrequency ablation of pulmonary vein was performed to determine the channel with dominant frequency. Threshold algorithm was used for signals which could be classified as type I and type II AF. Type III AF Signals which were highly fractionated or differentiated were evaluated for frequency content by performing Fast Fourier Transform. Data from Seven patients was collected and an episode of 180 ± 40 seconds was recorded and analyzed for each pulmonary vein that showed electrical activation. Frequency spectra for one second segment of signal for each channel were determined. The frequencies of channels were then compared to determine the channel with highest or dominant frequency. In most cases the frequency of a single channel varied erratically between 1 to 10 Hz for every subsequent one second segment which made DF detection among the channels unreliable and a single channel with dominant frequency could not be determined. A five second averaging for each channel did not produce a stable DF output and improvement was minimal. The erratic frequency behavior could be attributed to the spatial shift of micro- reentrant circuits or temporal variation in waveform over lap at the point of detection. To determine the DF more precisely either an increase in number of electrode or increase in time segment block for DF calculation is warranted. Increasing the time segment block will defeat the purpose of real time analysis thus an increase in number of electrode mapping the area of interest would be appropriate to resolve the issue.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Biomedical Engineering

Year dc:date.available

2005

Author dc:creator

• Yadav, Prashant

Contributors dc:contributor

• Dr. Martin Lenhardt

• radio
• pulmonary vein
• atrial fibrillation
• supra-ventricular arrhythmia
• lasso
• frequency
• Biomedical Engineering and Bioengineering
• Engineering

Statement dc:rights

• © The Author

Identifier

https://scholarscompass.vcu.edu/etd/1305

OAI identifier oai:identifier

oai:scholarscompass.vcu.edu:etd-2304