Reduction in Inappropriate ICD Therapy in MADIT-RIT Patients Without History of Atrial Tachyarrhythmia.
BACKGROUND
There are limited data whether history of atrial tachyarrhythmia (AT) modifies the risk of inappropriate ICD therapy, or the efficacy of novel ICD programming to reduce inappropriate ICD therapy events.


METHODS
In MADIT-RIT, we investigated the effects of novel ICD programming with high-rate cut-off VT zone ≥ 200 bpm (arm B), or 60-second delayed therapy in the VT zone 170-199 bpm (arm C), compared to conventional programming VT zone>170 bpm (arm A) on first inappropriate ICD therapy in those with or those without AT prior to enrollment.


RESULTS
In patients with prior AT (n = 203, 14%) there was a higher risk of inappropriate ICD therapy (HR = 2.10, 95% CI: 1.38-3.20, P < 0.001), and inappropriate ICD shock (HR = 2.56, 95% CI: 1.38-4.74, P = 0.003) compared to those with no prior AT. The effects of innovative programming to reduce inappropriate ICD therapy with either high-rate cut-off or delayed VT therapy were similar in patients with prior AT (arm B vs. A HR = 0.11, P < 0.001, arm C vs. A HR = 0.17, P < 0.001), and also in patients without prior AT before enrollment (arm B vs. A HR = 0.15, P < 0.001, arm C vs. A HR = 0.24, P < 0.001, interaction P-values >0.10 for all).


CONCLUSIONS
Novel ICD programming with a high-rate cut-off or delayed therapy is equally beneficial to reduce inappropriate ICD therapy in patients with or without prior AT, despite the lower risk of inappropriate ICD therapy in patients without prior AT.
University of Rochester Medical Center, Rochester, New York, USA.
Valentina
V
Kutyifa
University of Rochester Medical Center, Rochester, New York, USA.
Arthur J
AJ
Moss
The Henry Ford Hospital, Department of Cardiac Electrophysiology, Detroit, Michigan, USA.
Claudio
C
Schuger
University of Rochester Medical Center, Rochester, New York, USA.
Scott
S
McNitt
University of Rochester Medical Center, Rochester, New York, USA.
Bronislava
B
Polonsky
University of Rochester Medical Center, Rochester, New York, USA.
Anne-Christine H
AH
Ruwald
University of Rochester Medical Center, Rochester, New York, USA.
Martin H
MH
Ruwald
Cardiology Department, Duke University, Durham, North Carolina, USA.
James P
JP
Daubert
University of Rochester Medical Center, Rochester, New York, USA.
Wojciech
W
Zareba
D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D001282:Atrial Flutter / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D002170:Canada; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation*; D005060:Europe; D005260:Female; D006339:Heart Rate; D006801:Humans; D007557:Israel; D007564:Japan; D008297:Male; D008875:Middle Aged; D011322:Primary Prevention / Q000295:instrumentation* / Q000379:methods; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States
ICD programming; MADIT-RIT; atrial tachyarrhythmia; inappropriate ICD therapy; outcome