TY - JOUR
T1 - Effects of oral propafenone on defibrillation and pacing thresholds in patients receiving implantable cardioverter-defibrillators
AU - Stevens, Stephanie K.
AU - Haffajee, Charles I.
AU - Naccarelli, Gerald V.
AU - Schwartz, Kerry M.
AU - Luceri, Richard M.
AU - Packer, Douglas L.
AU - Rubin, Andrew M.
AU - Kowey, Peter R.
N1 - Funding Information:
From St. Elizabeth's Medical Center, Boston, Massachusetts; *University of Texas Medical School at Houston, Houston, Texas; tFlorida Heart Group, Orlando, Florida; :\[:HolyC ross Hospital, Fort Lauderdale, Florida; §Mayo Clinic, Rochester, Minnesota; and IlLankenau Hospital and Medical Research Center, Wynnewood, Pennsylvania. This study was sponsored by an educational grant from Knoll Pharmaceutical Company, Mount Olive, New Jersey. Dr. Kowey serves as a consultant to Knoll Pharmaceutical Co., Mount Olive, New Jersey. Manuscript received October 27, 1995; revised manuscript received January 26, 1996, accepted March 27, 1996. Address for correspondence: Dr. Stephanie K. Stevens, St. Elizabeth's Medical Center, Cardiovascular Division, 736 Cambridge Street, Boston, Massachusetts 02135.
PY - 1996/8
Y1 - 1996/8
N2 - Objectives. The effects of propafenone, a predominantly class IC antiarrhythmic drug, on defibrillation and pacing thresholds were evaluated in patients undergoing cardioverter-defibrillator implantation. Background. Previous studies have shown that the class IC agents encainide and flecainide may increase the energy requirements for pacing and defibrillation. Animal studies with propafenone have shown inconsistent results regarding its effect on defibrillation energy requirements. This report investigated the effects of propafenone on defibrillation and pacing thresholds in humans. Methods. After cardioverter-defibrillator implantation, 47 patients were enrolled in a double-blind, three-way parallel, randomized trial of 450 mg/day (Group 1) or 675 mg/day (Group 2) of oral propafenone or placebo (Group 3) for 3 to 7 days. Predischarge defibrillation and pacing thresholds after treatment were compared with baseline thresholds obtained at implantation. Results. There was no statistically significant difference between implantation and predischarge defibrillation thresholds in the three groups (Group 1: [mean ± SE] 11.0 ± 1.3 vs. 12.1 ± 1.5 J; Group 2: 11.5 ± 1.1 vs. 13.6 ± 1.3 J; Group 3: 12.5 ± 1.2 vs. 13.3 ± 1.6 J), and no significant difference between treatment groups was found with a 0.86 power to detect a 5-J difference between groups. Paired pulse width pacing thresholds at 2.8 V were compared in 14 patients. A small increase of 0.02 ms was noted at predischarge testing in patients treated with propafenone and placebo. Conclusions. Short-term oral propafenone (450 and 675 mg/day) does not significantly affect defibrillation or pacing thresholds. Concomitant use of propafenone in patients with implantable cardioverter-defibrillators with recurrent ventricular or atrial tachyarrhythmias should not interfere with proper device function.
AB - Objectives. The effects of propafenone, a predominantly class IC antiarrhythmic drug, on defibrillation and pacing thresholds were evaluated in patients undergoing cardioverter-defibrillator implantation. Background. Previous studies have shown that the class IC agents encainide and flecainide may increase the energy requirements for pacing and defibrillation. Animal studies with propafenone have shown inconsistent results regarding its effect on defibrillation energy requirements. This report investigated the effects of propafenone on defibrillation and pacing thresholds in humans. Methods. After cardioverter-defibrillator implantation, 47 patients were enrolled in a double-blind, three-way parallel, randomized trial of 450 mg/day (Group 1) or 675 mg/day (Group 2) of oral propafenone or placebo (Group 3) for 3 to 7 days. Predischarge defibrillation and pacing thresholds after treatment were compared with baseline thresholds obtained at implantation. Results. There was no statistically significant difference between implantation and predischarge defibrillation thresholds in the three groups (Group 1: [mean ± SE] 11.0 ± 1.3 vs. 12.1 ± 1.5 J; Group 2: 11.5 ± 1.1 vs. 13.6 ± 1.3 J; Group 3: 12.5 ± 1.2 vs. 13.3 ± 1.6 J), and no significant difference between treatment groups was found with a 0.86 power to detect a 5-J difference between groups. Paired pulse width pacing thresholds at 2.8 V were compared in 14 patients. A small increase of 0.02 ms was noted at predischarge testing in patients treated with propafenone and placebo. Conclusions. Short-term oral propafenone (450 and 675 mg/day) does not significantly affect defibrillation or pacing thresholds. Concomitant use of propafenone in patients with implantable cardioverter-defibrillators with recurrent ventricular or atrial tachyarrhythmias should not interfere with proper device function.
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U2 - 10.1016/0735-1097(96)00156-8
DO - 10.1016/0735-1097(96)00156-8
M3 - Article
C2 - 8800119
AN - SCOPUS:0030220114
SN - 0735-1097
VL - 28
SP - 418
EP - 422
JO - Journal of the American College of Cardiology
JF - Journal of the American College of Cardiology
IS - 2
ER -