The inefficacy of intravenous propafenone for rate control in atrial fibrillation.
The antiarrhythmic agent propafenone has been reported to prolong atrioventricular node conduction and may be suitable for rate control in atrial fibrillation (AF). To evaluate this, 10 patients (seven men and three women aged 29 to 67 years, mean +/- SD 48 +/- 14) were given intravenous propafenone during AF in both the supine and upright positions. Intracardiac catheters measured local electrograms from the high right atrium and right ventricular apex during AF. Atrial rate, ventricular rate and blood pressure were recorded in the control state and after head-up tilt with these measurements repeated after propafenone 1.5 mg/kg was infused over 5 mins. Four of 10 patients reverted to sinus rhythm. Propafenone increased the mean ventricular cycle length (496 +/- 147 versus 556 +/- 152 ms, P = 0.1), although this did not reach significance. In contrast, propafenone markedly increased the mean atrial cycle length (136 +/- 35 versus 226 +/- 39, P < 0.001). The mean ventricular cycle length reverted to baseline after tilt (447 +/- 103 ms) while the mean atrial cycle length decreased but not to baseline levels (170 +/- 21 ms). The authors conclude that intravenous propafenone is generally inadequate for rate control in AF, especially in the upright position.
Leather
R A
RA
Department of Medicine, University of Western Ontario, London.
Klein
G J
GJ
Murdoch
C
C
Yee
R
R
Leitch
J W
JW
D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011187:Posture; D011405:Propafenone / Q000008:administration & dosage*; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000188:drug therapy / Q000503:physiopathology
D011405:Propafenone