Electronic Theses and Dissertations

Identifier

2482

Date

2015

Document Type

Thesis

Degree Name

Master of Science

Major

Biomedical Engineering

Committee Chair

Amy L de Jongh Curry

Committee Member

John L Williams

Committee Member

David A Fitch

Abstract

Numerous clinical studies indicate the feasibility and safety of the use of internal atrial defibrillators to successfully treat atrial fibrillation (AF). However, the delivered energy to successfully defibrillate the atria is often painful for patients. This study aims to show the effects of small shifts in electrode placement on the defibrillation threshold (DFT) by computational simulations employing the use of an anatomically realistic human torso model. Electric fields were computed using COMSOL Multiphysics 5.1 for 10 electrode placement variations of 2 clinically relevant placements. The percent difference comparison between the two standard clinical configurations used show that a significantly higher (74%) DFT is needed to defibrillate the atria in the right atrium (RA) -> coronary sinus (CS) configuration when compared to the right atrium (RA) -> left atrium (LA) configuration. The largest percent difference calculated within RA -> LA variations (26%) occurs when the electrode in the RAis moved to its appendage, while the largest change in DFT calculated within the RA -> CS variations (24%) occurs when the electordes in the RA and CS are moved approximately 1-3 cm laterally and distally, respectively. These results indicate that small shifts in electrode placements have a significant effect on the DFT for internal atrial fibrillation. We suggest that optimizing electrode placement may be an important step toward lowering DFTs to tolerable levels for patients.

Comments

Data is provided by the student.

Library Comment

Dissertation or thesis originally submitted to the local University of Memphis Electronic Theses & dissertation (ETD) Repository.

Download

Share

COinS