Document Detail


Efficacy of a microwave antenna for ablation of the tricuspid valve--inferior vena cava isthmus in dogs as a treatment for type 1 atrial flutter.
MedLine Citation:
PMID:  15133355     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
INTRODUCTION: Radiofrequency catheter ablation of the tricuspid valve-inferior vena cava (TV-IVC) isthmus for treatment of atrial flutter (AFL), may in some cases require a large number of energy applications and a long procedure and fluoroscopy time. AIMS OF STUDY: Therefore, we studied the safety and efficacy of a 4 cm long microwave antenna mounted on a steerable 9Fr catheter for linear ablation of the TV-IVC isthmus. METHODS: In 6 anesthetized dogs, multi-electrode catheters were positioned in the coronary sinus (decapolar), at the His bundle (quadripolar) and around the TV annulus (decapolar) for pacing and recording atrial activation sequences before and after ablation. The microwave antenna was then positioned across the TV-IVC isthmus from the TV annulus (identified by equal A and V potentials) to the inferior vena cava with slight traction on the catheter to ensure adequate endocardial contact. Microwave energy was then applied at a fixed power for 120 seconds during each ablation attempt. Ablation was repeated until bi-directional isthmus block was demonstrated during pacing from the coronary sinus ostium and low lateral right atrium, respectively. RESULTS: Linear microwave ablation of the TV-IVC isthmus was completed in all ten dogs using a total of 2.6 +/- 1.17 energy applications per dog. Power was applied in a range of 45-50 watts. There were no acute procedural complications. Bi-directional TV-IVC isthmus block was achieved in all ten dogs, as demonstrated by a strictly descending activation wavefront in the ipsilateral atrial wall, during pacing from the CSO and LLRA respectively. In addition, after ablation conduction time to the LLRA during pacing from the CSO increased from 52 +/- 16.62 before to 87 +/- 12.74 msec (p <.05), and to the CSO during pacing from the LLRA from 51 +/- 12.43 before to 79.50 +/- 9.85 msec (p <.05). Gross and histological examination of the TV-IVC isthmus after ablation revealed continuous transmural lesions, ranging from 3-5 mm in width, spanning the entire TV-IVC isthmus in all ten dogs. CONCLUSIONS: (1) Microwave ablation of the TV-IVC isthmus was safe and effective in this study. (2) Ablation of the entire width and thickness of the TV-IVC isthmus can be rapidly achieved using a long microwave antenna in a fixed trans-isthmus position.
Authors:
Atsushi Iwasa; James Storey; Biguang Yao; L Bing Liem; Gregory K Feld
Related Documents :
2301225 - Retrograde left atrial catheterization with a new steerable cardiac catheter.
10966285 - Transthoracic intracardiac catheters in pediatric patients recovering from congenital h...
2407395 - Catheter ablation using radiofrequency energy.
9254765 - Selective catheter ablation of the slow atrioventricular nodal pathway for atrial fibri...
7969985 - Homolateral hemiparesis as an early sign of cerebellar mass effect.
9134615 - A silicone rubber mould of the heart.
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of interventional cardiac electrophysiology : an international journal of arrhythmias and pacing     Volume:  10     ISSN:  1383-875X     ISO Abbreviation:  J Interv Card Electrophysiol     Publication Date:  2004 Jun 
Date Detail:
Created Date:  2004-05-10     Completed Date:  2004-11-08     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  9708966     Medline TA:  J Interv Card Electrophysiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  191-8     Citation Subset:  IM    
Affiliation:
Cardiac Electrophysiology Program, Division of Cardiology, Department of Medicine, University of California, San Diego, CA, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Atrial Flutter / surgery*
Body Surface Potential Mapping
Cardiac Pacing, Artificial
Catheter Ablation*
Disease Models, Animal
Dogs
Endocardium / cytology,  pathology
Heart Atria / pathology,  surgery
Heart Conduction System / pathology*,  surgery*
Heart Septum / pathology,  surgery
Microwaves*
Models, Cardiovascular
Myocytes, Cardiac / pathology
Necrosis
Treatment Outcome
Tricuspid Valve / pathology*,  surgery*
Vena Cava, Inferior / pathology*,  surgery*

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


Previous Document:  Sarcoidosis presenting as metastatic bony disease. A case report and review of the literature on ver...
Next Document:  Transmembraneous irrigation of multipolar radiofrequency ablation catheters: induction of linear les...