FREQUENCY ESTIMATION FOR ATRIAL FIBRILLATION FROM HUMAN STUDIES

2016 ◽  
Vol 78 (7-4) ◽  
Author(s):  
Anita Ahmad
Keyword(s):  
Atrial Fibrillation ◽  
European Union ◽  
High Frequency ◽  
Frequency Estimation ◽  
Dominant Frequency ◽  
High Frequency Stimulation ◽  
The European Union ◽  
Mortality And Morbidity ◽  
Spectral Techniques ◽  
Frequency Stimulation

Atrial Fibrillation (AF) is the most common disorder of the heart rhythms. There are about 2.3 million people in United States and 4.5 million people in the European Union with AF [1]. It is also one of the factors that may contribute to mortality and morbidity. Researchers who apply spectral techniques show that certain areas of the atria can have higher activation frequencies than other areas. Frequency analysis is used to measure changes in Dominant Frequency (DF). We access the electrical propagation inside the atria by spectrogram plotting and examining the effect of high frequency stimulation on human.

Isoprenaline and Atropine Effect on Atrial Arrhythmias Study

2010 ◽  
Author(s):  
Anita Ahmad ◽  
Fernando S. Schlindwein ◽  
Jiun H. Tuan ◽  
G. Andre Ng
Keyword(s):  
United States ◽  
Atrial Fibrillation ◽  
European Union ◽  
Frequency Analysis ◽  
Dominant Frequency ◽  
Atrial Arrhythmias ◽  
The European Union ◽  
Mortality And Morbidity ◽  
Spectral Techniques ◽  
Frequency Changes

Atrial Fibrillation (AF) is the most common disorder of the heart rhythms. There are about 2.3 million people in United States and 4.5 million people in the European Union with AF [Go et.al, 2001]. It is also one of the factors that may contribute to mortality and morbidity. Researchers who apply spectral techniques show that certain areas of the atria can have higher activation frequencies than other areas. Frequency analysis is used to measure changes in Dominant Frequency (DF). We access the electrical propagation inside the atria by spectrogram plotting and examining the effect of isoprenaline and atropine on frequency changes.

Abstract 19466: Preliminary Experience Using Multiplexed Imaging of the Sympathetic Autonomic Nervous System - Impact on Outcome of Catheter Ablation of Atrial Fibrillation

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Sabine Ernst ◽  
Francesca Menichetti ◽  
Rafael Baavour ◽  
Nathaniel Roth ◽  
Jamshed Bomanji ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Catheter Ablation ◽  
High Frequency ◽  
De Novo ◽  
Imaging Study ◽  
High Frequency Stimulation ◽  
High Uptake ◽  
Af Ablation ◽  
Uptake Sites ◽  
Frequency Stimulation

Introduction: Catheter ablation of ganglionated plexi (GP) as an add on to pulmonary vein (PV) isolation has been reported to significantly improve outcome of atrial fibrillation (AF) ablation. In order to facilitate localization of these GPs, a novel imaging study is proposed, assessing the uptake of iodine-123 metaiodobenzylguanidine (mIBG, an analog of norepinephrine)in combination with 3D surface reconstruction from contrast computed tomography (cCT) or cardiac magnetic resonance (CMR). Methods: A total of 8 patients (5 male, median age 58 yrs) underwent mIBG SPECT using a dedicated cardiac camera (D-SPECT, SUMO, Spectrum Dynamics). This data was merged with 3D CMR or cCT and finally imported into CARTO (Biosense Webster). Using the individual mediastinum uptake as a normalizing factor, high uptake sites in the epicardial fat pads around the left atrium (LA) were identified. Five patients had paroxysmal AF whilst 3 present in persistent (n=2) or longstanding persistent (n=1) AF. Only 3 patients were treated de-novo, with the remaining failing in median 2 previous ablation procedures. Invasively, high uptake sites were mapped using high frequency stimulation (HFS) to confirm GP locations, which were subsequently ablated. PV (re) isolation and CFAE ablation was performed as needed. Results: Both the mIBG and CT or CMR scans were performed without complications. Focal mIBG uptake sites corresponded to anatomical GP sites, but individual variations of additional GPs were observed. Using HFS stimulation, GP sites were confirmed, but exact localization was highly depending on accurate image registration. Median follow-up of 9.2 months with all PAF and persistent AF patients in SR (1 AT redo), while the long-standing AF relapsed. Conclusion: The combination of mIBG SPECT and 3D anatomical imaging (SUMO protocol) provides a novel type of “road map” for localizing GPs during AF ablation. GPs were variable in number and location and were invasively confirmed using high frequency stimulation. Addition of GP ablation to standard AF ablation strategies seems beneficial in patients with paroxysmal or persistent AF. Further studies in larger patient cohorts are needed to confirm these initial observations.

scholarly journals Is Vagal Response During Left Atrial Ganglionated Plexi Stimulation a Normal Phenomenon?

2019 ◽  
Vol 12 (10) ◽  
Author(s):  
Kazuki Iso ◽  
Yasuo Okumura ◽  
Ichiro Watanabe ◽  
Koichi Nagashima ◽  
Keiko Takahashi ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pulse Duration ◽  
High Frequency ◽  
Left Atrial ◽  
Accessory Pathway ◽  
High Frequency Stimulation ◽  
Ganglionated Plexi ◽  
Multivariate Adjustment ◽  
Frequency Stimulation ◽  
The Mean

Background: Ganglionated plexi (GPs) play an important role in both the initiation and maintenance of atrial fibrillation (AF). GPs can be located by using continuous high-frequency stimulation (HFS) to elicit a vagal response, but whether the vagal response phenomenon is common to patients without AF is unknown. Methods: HFS of the left atrial GPs was performed in 42 patients (aged 58.0±10.2 years) undergoing ablation for AF and 21 patients (aged 53.2±12.8 years) undergoing ablation for a left-sided accessory pathway. The HFS (20 Hz, 25 mA, 10-ms pulse duration) was applied for 5 seconds at 3 sites within the presumed anatomic area of each of the 5 major left atrial GPs (for a total of 15 sites per patient). We defined vagal response to HFS as prolongation of the R-R interval by >50% in comparison to the mean pre-HFS R-R interval averaged over 10 beats and active-GP areas as areas in which a vagal response was elicited. Results: Overall, more active-GP areas were found in the AF group patients than in the non-AF group patients, and at all 5 major GPs, the maximum R-R interval during HFS was significantly prolonged in the AF patients. After multivariate adjustment, association was established between the total number of vagal response sites and the presence of AF. Conclusions: The significant increase in vagal responses elicited in patients with AF compared with responses in non-AF patients suggests that vagal responses to HFS reflect abnormally increased GP activity specific to AF substrates.

Localization of left atrial autonomic ganglionated plexuses using endocardial and epicardial high frequency stimulation in patients with atrial fibrillation

Heart Rhythm ◽  
2005 ◽  
Vol 2 (5) ◽  
pp. S10-S11 ◽  
Author(s):  
Hiroshi Nakagawa ◽  
Benjamin J. Scherlag ◽  
Deborah Lockwood ◽  
Randall K. Wolf ◽  
Marvin Peyton ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
High Frequency ◽  
Left Atrial ◽  
High Frequency Stimulation ◽  
Frequency Stimulation

scholarly journals High frequency stimulation for verifying durable lesions during atrial fibrillation ablation.

2020 ◽  
Author(s):  
Kazuo Kato ◽  
Shin Hasegawa ◽  
Shun Kikuchi ◽  
Yukihiro Uehara ◽  
Nobuo Ishiguro ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
High Frequency ◽  
Atrial Fibrillation Ablation ◽  
High Frequency Stimulation ◽  
Frequency Stimulation
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