Ulster University Logo

Ulster Institutional Repository

Waveform optimisation for internal cardioversion of atrial fibrillation

Biomedical Sciences Research Institute Computer Science Research Institute Environmental Sciences Research Institute Nanotechnology & Advanced Materials Research Institute

Kodoth, V, Castro, NC, Glover, BM, Anderson, JMCC, Escalona, OJ, Lau, E and Manoharan, G (2011) Waveform optimisation for internal cardioversion of atrial fibrillation. Journal of Electrocardiology, 44 (6). pp. 689-693. [Journal article]

Full text not available from this repository.

URL: http://www.jecgonline.com/article/S0022-0736(11)00310-4/fulltext

Abstract

Introduction: A novel atrial defibrillator was developed at the Royal Victoria Hospital in collaboration with the Nanotechnology and Integrated Bio-Engineering Centre (NIBEC), University of Ulster. This device is powered by an external pulse of radiofrequency (RF) energy and designed to cardiovert using low tilt monophasic (LTMW) and low tilt biphasic waveform (LTBW), 12 ms pulse width. This study compared the safety and efficacy of LTMW with LTBW for transvenous cardioversion of atrial fibrillation (AF).Methods: Patients with persistent AF and with previous history of failed external cardioversion were randomised to LTMW or LTBW. Warfarin INR level was maintained in between 2-3 for 4 weeks prior cardioversion. St Jude’s defibrillating catheter was positioned in the distal coronary sinus and right atrium and connected to the defibrillator via a junction box. After a test shock using a dummy load, patient was cardioverted in a step up progression from 50V to 300V. Shock success was defined as return of sinus rhythm for >/=30 seconds. If cardioversion was unsuccessful at peak voltage patient was crossed over to the other arm of waveform type and cardioverted at peak voltage. Results: Thirty patients (50%) were equally randomised to LTBW and LTMW. Seven out of 15 (46%) cardioverted to sinus rhythm with LTBW and 1/15 (6%) with LTMW (p<0.035). Including crossover patient’s 14 patients (46%) converted to sinus rhythm. After cross over 4 patients were cardioverted with LTBW and 2 with LTMW. Overall mean voltage, current and energy used for cardioversion was 270.53+/-35.96 Volts, 3.68+/-0.80 Amps, 9.12+/-3.73 Joules and intracardiac impedance was 70.82+/-13.46 Ohms. For patients who were successfully cardioverted mean voltage, current, energy and intracardiac impedance were 268.28+/-42.41 V, 3.52+/-0.63 A, 8.51+/-3.16 J and 73.92+/-12.01 Ohms. There were no major adverse complications during the study. Cardiac markers measured post cardioversion were unremarkable.Conclusion: LTBW was more efficacious for low energy transvenous cardioversion of AF. A significant proportion of patients were successfully cardioverted to sinus rhythm with low energy. Radiofrequency powered defibrillation can be safely used for transvenous cardioversion of AF.

Item Type:Journal article
Keywords:Atrial Fibrillation, Cardioversion, Defibrillator, ECG, Biphasic Waveform, Cardiology
Faculties and Schools:Faculty of Computing & Engineering
Faculty of Computing & Engineering > School of Engineering
Research Institutes and Groups:Engineering Research Institute
Engineering Research Institute > Nanotechnology & Integrated BioEngineering Centre (NIBEC)
ID Code:19861
Deposited By:Professor Omar Escalona
Deposited On:27 Sep 2011 15:20
Last Modified:13 Sep 2012 10:14

Repository Staff Only: item control page