TY - JOUR
T1 - Low-energy transvenous cardioversion defibrillation of atrial tachyarrhythmias in the canine
T2 - An assessment of electrode configurations and monophasic pulse sequencing
AU - Benditt, David G.
AU - Dunbar, David
AU - Fetter, Joseph
AU - Sakaguchi, Scott
AU - Lurie, Keith G.
AU - Adler, Stuart W.
PY - 1994/4
Y1 - 1994/4
N2 - Prevention of recurrent atrial fibrillation and flutter remains a difficult clinical problem. Consequently, development of an easily implantable automatic atrial cardioverter defibrillator is appealing. In this context we have examined the feasibility of intracavitary low-energy shocks delivered via transvenously positioned electrodes for termination of induced atrial tachyarrhythmias in canine models. This study extends these observations with use of single-pathway (5 msec pulse duration) and dual-pathway sequential ( 5 5 msec, 0.2 msec separation) shocks of varying leading edge voltages (100 to 400 V) in a closed-chest canine talc-pericarditis model. Bipolar 9.5 French electrode catheters (electrode surface areas, 0.62 cm2) were positioned at the superior vena cava-right atrium (SVC-RA) junction (labeled SVC) and right ventricular (RV) apex, with a subcutaneous plate over the chest wall. For single-pathway shocks, overall treatment effectiveness was comparable among the three vectors tested (RV apex to SVC, 35%; RV apex to subcutaneous plate, 17%; and SVC to subcutaneous plate, 35%). Furthermore, there was no evident relationship between leading edge voltage and shock effectiveness. In conrast, although each of the dual-pathway shock vector combinations tested also showed similar overall effectiveness, there was an apparent dose-response effect as leading edge voltage increased. The SVC (common) to RV apex (pulse 1) and subcutaneous plate (pulse 2) achieved 60% effectiveness at 400 V (approximately 4 joules). Thus this study provides additional evidence favoring feasibility of low-energy transvenous atrial cardioversion defibrillation. However, further refinement of energy delivery is essential for the implantable automatic atrial cardioverter defibrillator concept to become clinically accepted.
AB - Prevention of recurrent atrial fibrillation and flutter remains a difficult clinical problem. Consequently, development of an easily implantable automatic atrial cardioverter defibrillator is appealing. In this context we have examined the feasibility of intracavitary low-energy shocks delivered via transvenously positioned electrodes for termination of induced atrial tachyarrhythmias in canine models. This study extends these observations with use of single-pathway (5 msec pulse duration) and dual-pathway sequential ( 5 5 msec, 0.2 msec separation) shocks of varying leading edge voltages (100 to 400 V) in a closed-chest canine talc-pericarditis model. Bipolar 9.5 French electrode catheters (electrode surface areas, 0.62 cm2) were positioned at the superior vena cava-right atrium (SVC-RA) junction (labeled SVC) and right ventricular (RV) apex, with a subcutaneous plate over the chest wall. For single-pathway shocks, overall treatment effectiveness was comparable among the three vectors tested (RV apex to SVC, 35%; RV apex to subcutaneous plate, 17%; and SVC to subcutaneous plate, 35%). Furthermore, there was no evident relationship between leading edge voltage and shock effectiveness. In conrast, although each of the dual-pathway shock vector combinations tested also showed similar overall effectiveness, there was an apparent dose-response effect as leading edge voltage increased. The SVC (common) to RV apex (pulse 1) and subcutaneous plate (pulse 2) achieved 60% effectiveness at 400 V (approximately 4 joules). Thus this study provides additional evidence favoring feasibility of low-energy transvenous atrial cardioversion defibrillation. However, further refinement of energy delivery is essential for the implantable automatic atrial cardioverter defibrillator concept to become clinically accepted.
UR - http://www.scopus.com/inward/record.url?scp=0028219194&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028219194&partnerID=8YFLogxK
U2 - 10.1016/0002-8703(94)90078-7
DO - 10.1016/0002-8703(94)90078-7
M3 - Article
C2 - 8160604
AN - SCOPUS:0028219194
SN - 0002-8703
VL - 127
SP - 994
EP - 1003
JO - American Heart Journal
JF - American Heart Journal
IS - 4 PART 2
ER -