Intravenous amiodarone for recurrent sustained hypotensive ventricular tachyarrhythmias. Intravenous Amiodarone Multicenter Trial Group.
OBJECTIVE
We sought to determine the response rate and safety of intravenous amiodarone in patients with ventricular tachyarrhythmias refractory to standard therapies.


BACKGROUND
Numerous small retrospective reports suggest a response of refractory ventricular tachyarrhythmias to intravenous amiodarone, yet no controlled prospective trials exist.


METHODS
Two hundred seventy-three patients with recurrent hypotensive ventricular tachyarrhythmias refractory to lidocaine, procainamide and bretylium were randomized to receive one of three doses of intravenous amiodarone: 525, 1,050 or 2,100 mg/24 h (mean [+/- SE] dose 743.7 +/- 418.7, 1,175.2 +/- 483.7, 1,921.2 +/- 688.8 mg, respectively) by continuous infusion over 24 h.


RESULTS
Of the 273 patients, 110 (40.3% response rate) survived 24 h without another hypotensive ventricular tachyarrhythmic event while being treated with intravenous amiodarone as a single agent (primary end point). A significant difference in the time to first recurrence of ventricular tachyarrhythmia (post hoc analysis) over the first 12 h was observed when the combined 1,050- and 2,100-mg dose groups were compared with the 525-mg dose group (p = 0.046). The number of supplemental (150 mg) infusions of intravenous amiodarone (given for breakthrough destabilizing tachyarrhythmias) during hours 0 to 6 (prespecified secondary end point) was significantly greater in the 525-mg dose group than in the 2,100-mg dose group (1.09 +/- 1.57 vs. 0.51 +/- 0.97, p = 0.0043). However, there was no clear dose-response relation observed in this trial with respect to success rates (primary end point), time to first recurrence of tachyarrhythmia (post hoc analysis) or mortality (secondary end point) over 24 h.


CONCLUSIONS
Intravenous amiodarone is a relatively safe therapy for ventricular tachyarrhythmias refractory to other medications.
Arrhythmia Service, St. Francis Hospital, Roslyn, New York 11576, USA.
J H
JH
Levine
A
A
Massumi
M M
MM
Scheinman
R A
RA
Winkle
E V
EV
Platia
D A
DA
Chilson
A
A
Gomes
R L
RL
Woosley
D000638:Amiodarone / Q000008:administration & dosage* / Q000009:adverse effects; D000704:Analysis of Variance; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001919:Bradycardia / Q000139:chemically induced; D002423:Cause of Death; D016009:Chi-Square Distribution; D018572:Disease-Free Survival; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006333:Heart Failure / Q000139:chemically induced; D006801:Humans; D007022:Hypotension / Q000139:chemically induced / Q000150:complications*; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D015996:Survival Rate; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000188:drug therapy* / Q000401:mortality; D014693:Ventricular Fibrillation / Q000139:chemically induced
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone