Dual-chamber versus single-chamber detection enhancements for implantable defibrillator rhythm diagnosis: the detect supraventricular tachycardia study.
BACKGROUND
Delivery of inappropriate shocks caused by misdetection of supraventricular tachycardia (SVT) remains a substantial complication of implanted cardioverter/defibrillator (ICD) therapy. Whether use of optimally programmed dual-chamber ICDs lowers this risk compared with that in single-chamber ICDs is not clear.


RESULTS
Subjects with a clinical indication for ICD (n=400) at 27 participating centers received dual-chamber ICDs and were randomly assigned to strictly defined optimal single- or dual-chamber detection in a single-blind manner. Programming minimized ventricular pacing. The primary end point was the proportion of SVT episodes inappropriately detected from the time of programming until crossover or end of study. On a per-episode basis, 42% of the episodes in the single-chamber arm and 69% of the episodes in the dual-chamber arm were due to SVT. Mortality (3.5% in both groups) and early study withdrawal (14% single-chamber, 11% dual-chamber) were similar in both groups. The rate of inappropriate detection of SVT was 39.5% in the single-chamber detection arm compared with 30.9% in the dual-chamber arm. The odds of inappropriate detection were decreased by almost half with the use of the dual-chamber detection enhancements (odds ratio, 0.53; 95% confidence interval, 0.30 to 0.94; P=0.03).


CONCLUSIONS
Dual-chamber ICDs, programmed to optimize detection enhancements and to minimize ventricular pacing, significantly decrease inappropriate detection.
Friedman
Paul A
PA
Division of Cardiovascular Diseases, Mayo Clinic, 200 First St SW, Rochester, Minnesota 55905, USA.
McClelland
Robyn L
RL
Bamlet
William R
WR
Acosta
Helbert
H
Kessler
David
D
Munger
Thomas M
TM
Kavesh
Neal G
NG
Wood
Mark
M
Daoud
Emile
E
Massumi
Ali
A
Schuger
Claudio
C
Shorofsky
Stephen
S
Wilkoff
Bruce
B
Glikson
Michael
M
D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D001283:Atrioventricular Node / Q000502:physiology; D002304:Cardiac Pacing, Artificial / Q000379:methods; D016001:Confidence Intervals; D018592:Cross-Over Studies; D017147:Defibrillators, Implantable / Q000009:adverse effects / Q000592:standards*; D003937:Diagnosis, Differential; D004554:Electric Countershock / Q000295:instrumentation* / Q000379:methods; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D004867:Equipment Design; D004868:Equipment Failure; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D013617:Tachycardia, Supraventricular / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy