TY - JOUR
T1 - Low-energy multistage atrial defibrillation therapy terminates atrial fibrillation with less energy than a single shock
AU - Li, Wenwen
AU - Janardhan, Ajit H.
AU - Fedorov, Vadim V.
AU - Sha, Qun
AU - Schuessler, Richard B.
AU - Efimov, Igor R.
PY - 2011/12
Y1 - 2011/12
N2 - Background-Implantable device therapy of atrial fibrillation (AF) is limited by pain from high-energy shocks. We developed a low-energy multistage defibrillation therapy and tested it in a canine model of AF. Methods and Results-AF was induced by burst pacing during vagus nerve stimulation. Our novel defibrillation therapy consisted of 3 stages: stage (ST) 1 (1-4 low-energy biphasic [BP] shocks), ST2 (6-10 ultralow-energy monophasic [MP] shocks), and ST3 (antitachycardia pacing). First, ST1 testing compared single or multiple MP and BP shocks. Second, several multistage therapies were tested: ST1 versus ST1+ST3 versus ST1+ST2+ST3. Third, 3 shock vectors were compared: superior vena cava to distal coronary sinus, proximal coronary sinus to left atrial appendage, and right atrial appendage to left atrial appendage. The atrial defibrillation threshold (DFT) of 1 BP shock was <1 MP shock (0.55±0.1 versus 1.38±0.31 J, P=0.003). Two to 3 BP shocks terminated AF with lower peak voltage than 1 BP or 1 MP shock and with lower atrial DFT than 4 BP shocks. Compared with ST1 therapy alone, ST1+ST3 lowered the atrial DFT moderately (0.51±0.46 versus 0.95±0.32 J, P=0.036), whereas 3-stage therapy (ST1+ST2+ST3) dramatically lowered the atrial DFT (0.19±0.12 versus 0.95±0.32 J for ST1 alone, P=0.0012). Finally, the 3-stage therapy was equally effective for all studied vectors. Conclusions-Three-stage electrotherapy significantly reduces the AF DFT and opens the door to low-energy atrial defibrillation at or below the pain threshold.
AB - Background-Implantable device therapy of atrial fibrillation (AF) is limited by pain from high-energy shocks. We developed a low-energy multistage defibrillation therapy and tested it in a canine model of AF. Methods and Results-AF was induced by burst pacing during vagus nerve stimulation. Our novel defibrillation therapy consisted of 3 stages: stage (ST) 1 (1-4 low-energy biphasic [BP] shocks), ST2 (6-10 ultralow-energy monophasic [MP] shocks), and ST3 (antitachycardia pacing). First, ST1 testing compared single or multiple MP and BP shocks. Second, several multistage therapies were tested: ST1 versus ST1+ST3 versus ST1+ST2+ST3. Third, 3 shock vectors were compared: superior vena cava to distal coronary sinus, proximal coronary sinus to left atrial appendage, and right atrial appendage to left atrial appendage. The atrial defibrillation threshold (DFT) of 1 BP shock was <1 MP shock (0.55±0.1 versus 1.38±0.31 J, P=0.003). Two to 3 BP shocks terminated AF with lower peak voltage than 1 BP or 1 MP shock and with lower atrial DFT than 4 BP shocks. Compared with ST1 therapy alone, ST1+ST3 lowered the atrial DFT moderately (0.51±0.46 versus 0.95±0.32 J, P=0.036), whereas 3-stage therapy (ST1+ST2+ST3) dramatically lowered the atrial DFT (0.19±0.12 versus 0.95±0.32 J for ST1 alone, P=0.0012). Finally, the 3-stage therapy was equally effective for all studied vectors. Conclusions-Three-stage electrotherapy significantly reduces the AF DFT and opens the door to low-energy atrial defibrillation at or below the pain threshold.
KW - Atrial fibrillation
KW - Cardioversion
KW - Defibrillation
KW - Vagal nerve stimulation
UR - http://www.scopus.com/inward/record.url?scp=84863337831&partnerID=8YFLogxK
U2 - 10.1161/CIRCEP.111.965830
DO - 10.1161/CIRCEP.111.965830
M3 - Article
C2 - 21980076
AN - SCOPUS:84863337831
VL - 4
SP - 917
EP - 925
JO - Circulation: Arrhythmia and Electrophysiology
JF - Circulation: Arrhythmia and Electrophysiology
SN - 1941-3149
IS - 6
ER -