Intravenous diltiazem for the treatment of patients with atrial fibrillation or flutter and moderate to severe congestive heart failure.
The objective of this multicenter, randomized, double-blind, placebo-controlled study was to determine the safety and efficacy of intravenous diltiazem in the treatment of 37 patients with rapid (ventricular rate, mean +/- SD 142 +/- 17 beats/min) atrial fibrillation or flutter and moderate to severe congestive heart failure (ejection fraction, mean +/- SD 36 +/- 14%; New York Heart Association class III [23 patients], class IV [14 patients]). During the double-blind portion of the study, patients received either intravenous diltiazem, 0.25 mg/kg over 2 minutes, or placebo followed 15 minutes later by diltiazem or placebo, 0.35 mg/kg over 2 minutes, if the first dose was tolerated but ineffective. Placebo nonresponders were given open-label intravenous diltiazem in a similar fashion as in the double-blind portion of the study. In the double-blind part of the study, 21 (18 with 0.25 mg/kg, 3 with an additional 0.35 mg/kg) of the 22 patients (95%) responded to diltiazem, and 0 of 15 patients (0%) responded to placebo (p < 0.001). All 15 patients (13 with 0.25 mg/kg and 2 with an additional 0.35 mg/kg) who received placebo during the double-blind period had a therapeutic response to diltiazem during open-label therapy. Overall, 36 of 37 patients (97%) had a therapeutic response to intravenous diltiazem. Heart rate response to diltiazem after the 2-minute bolus infusions consisted of a > or = 20% decrease in heart rate from baseline in 36 patients; in addition, 17 patients also had heart rates decreased to < 100 beats/min, whereas no patient had conversion to sinus rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)
Goldenberg
I F
IF
Minneapolis Heart Institute, Minnesota 55407.
Lewis
W R
WR
Dias
V C
VC
Heywood
J T
JT
Pedersen
W R
WR
D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy*; D001282:Atrial Flutter / Q000150:complications / Q000188:drug therapy*; D004110:Diltiazem / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006333:Heart Failure / Q000150:complications*; D006801:Humans; D007022:Hypotension / Q000139:chemically induced; D007275:Injections, Intravenous; D008297:Male; D013997:Time Factors
D004110:Diltiazem