BACKGROUND: The relationship between the defibrillation threshold (DFT) and total mortality is unclear. METHODS: A university hospital prospectively maintained implantable defibrillator (ICD) database identified 508 patients who underwent ICD implantation and had DFT testing performed at implant. Patients were placed in one of three groups based on the implant DFT (high (≥20 J), moderate (19-11 J), or low DFT (≤10 J)). RESULTS: Sixty-seven patients had a high DFT, 216 had a moderate DFT, and 225 had a low DFT. The mean left ventricular ejection fraction (LVEF) was 0.25, 0.28, and 0.30 in the high, moderate, and low DFT groups, respectively, (p = 0.04). There were significantly more patients with a subcutaneous electrode in the high DFT group (p < 0.001), more patients taking amiodarone (p < 0.001), and more patients on oral anticoagulation (p = 0.04). There were a total of 140 deaths during the follow-up period (mean 3.2 ± 1.7 years). There were 24 deaths in the high DFT group (35.8%), 62 in the moderate DFT group (28.7%), and 54 in the low DFT group (24.0%) (p = 0.05). Implant DFT was a significant predictor of mortality (p = 0.01), as was age, LVEF (p < 0.001), CAD (p = 0.01), amiodarone use (p = 0.02), and hematoma at implant (p = 0.01). An elevated DFT was an independent predictor of mortality after controlling for all significant univariate variables (p = 0.004). CONCLUSIONS: A high-implant DFT predicts an adverse prognosis, even when an adequate ICD safety margin is present.
BACKGROUND: The relationship between the defibrillation threshold (DFT) and total mortality is unclear. METHODS: A university hospital prospectively maintained implantable defibrillator (ICD) database identified 508 patients who underwent ICD implantation and had DFT testing performed at implant. Patients were placed in one of three groups based on the implant DFT (high (≥20 J), moderate (19-11 J), or low DFT (≤10 J)). RESULTS: Sixty-seven patients had a high DFT, 216 had a moderate DFT, and 225 had a low DFT. The mean left ventricular ejection fraction (LVEF) was 0.25, 0.28, and 0.30 in the high, moderate, and low DFT groups, respectively, (p = 0.04). There were significantly more patients with a subcutaneous electrode in the high DFT group (p < 0.001), more patients taking amiodarone (p < 0.001), and more patients on oral anticoagulation (p = 0.04). There were a total of 140 deaths during the follow-up period (mean 3.2 ± 1.7 years). There were 24 deaths in the high DFT group (35.8%), 62 in the moderate DFT group (28.7%), and 54 in the low DFT group (24.0%) (p = 0.05). Implant DFT was a significant predictor of mortality (p = 0.01), as was age, LVEF (p < 0.001), CAD (p = 0.01), amiodarone use (p = 0.02), and hematoma at implant (p = 0.01). An elevated DFT was an independent predictor of mortality after controlling for all significant univariate variables (p = 0.004). CONCLUSIONS: A high-implant DFT predicts an adverse prognosis, even when an adequate ICD safety margin is present.
Authors: Stefan H Hohnloser; Paul Dorian; Robin Roberts; Michael Gent; Carsten W Israel; Eric Fain; Jean Champagne; Stuart J Connolly Journal: Circulation Date: 2006-07-03 Impact factor: 29.690
Authors: Arthur J Moss; Wojciech Zareba; W Jackson Hall; Helmut Klein; David J Wilber; David S Cannom; James P Daubert; Steven L Higgins; Mary W Brown; Mark L Andrews Journal: N Engl J Med Date: 2002-03-19 Impact factor: 91.245
Authors: Gust H Bardy; Kerry L Lee; Daniel B Mark; Jeanne E Poole; Douglas L Packer; Robin Boineau; Michael Domanski; Charles Troutman; Jill Anderson; George Johnson; Steven E McNulty; Nancy Clapp-Channing; Linda D Davidson-Ray; Elizabeth S Fraulo; Daniel P Fishbein; Richard M Luceri; John H Ip Journal: N Engl J Med Date: 2005-01-20 Impact factor: 91.245
Authors: Andrea M Russo; William Sauer; Edward P Gerstenfeld; Henry H Hsia; David Lin; Joshua M Cooper; Sanjay Dixit; Ralph J Verdino; Hemal M Nayak; David J Callans; Vickas Patel; Francis E Marchlinski Journal: Heart Rhythm Date: 2005-05 Impact factor: 6.343
Authors: Denice M Hodgson; Mary R Olsovsky; Stephen R Shorofsky; Barry Daly; Michael R Gold Journal: Pacing Clin Electrophysiol Date: 2002-04 Impact factor: 1.976