Upper limit of vulnerability determination during implantable cardioverter-defibrillator placement to minimize ventricular fibrillation inductions.
The defibrillation threshold (DFT) and upper limit of vulnerability (ULV) were determined using step-down protocols in 50 patients who underwent implantable cardioverter-defibrillator placement or testing. The sensitivity and specificity of each ULV energy level was assessed for detecting an increased DFT, correlation of the DFT and ULV, and optimal shock timing for ULV determination. A ULV <10 or 11 J (failure to induce ventricular fibrillation with 10- to 11-J shocks) was 100% predictive of an acceptable DFT and may be sufficient to exclude unacceptable DFTs in 60% of implantable cardioverter-defibrillator recipients. All 4 shocks used to scan the peak of the T wave during ULV testing were necessary for accurate ULV determination.
Glikson
Michael
M
Sheba Medical Center and Tel Aviv University, Tel Hashomer, Israel.
Gurevitz
Osnat T
OT
Trusty
Jane M
JM
Sharma
Vinod
V
Luria
David M
DM
Eldar
Michael
M
Shen
Win-Kuang
WK
Rea
Robert F
RF
Hammill
Stephen C
SC
Friedman
Paul A
PA
D000368:Aged; D017147:Defibrillators, Implantable; D004560:Electricity; D004562:Electrocardiography; D005260:Female; D006331:Heart Diseases / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment; D014693:Ventricular Fibrillation / Q000209:etiology* / Q000517:prevention & control*