September 1, 1980Open Access
Response of atrial flutter to overdrive atrial pacing and intravenous disopyramide phosphate, singly and in combination.
Structured PICO
Does overdrive atrial pacing combined with intravenous disopyramide terminate atrial flutter in patients with spontaneous paroxysms?
P
Population
10 patients with spontaneous paroxysms of atrial flutter (2 with Wolff-Parkinson-White syndrome, 3 with Lown-Ganong-Levine syndrome, 1 with concealed accessory atrioventricular connection)
I
Intervention
Overdrive atrial pacing (2.5 s or 5 s bursts at 10, 50, or 100 beats/min faster than intrinsic rate) and intravenous disopyramide phosphate (2 mg/kg over 5 minutes), singly and in combination
O
Outcome
Termination of atrial flutter and conversion to sinus rhythmsurrogate
The combination of overdrive atrial pacing and intravenous disopyramide is highly effective for terminating atrial flutter, offering a potential alternative to direct current cardioversion.
Abstract
Ten patients who suffered spontaneous paroxysms of atrial flutter were investigated by electrophysiological techniques. Two had overt Wolff-Parkinson-White syndrome; three Lown-Ganong-Levine syndrome; and one a concealed accessory atrioventricular connection. Atrial flutter was initiated, at study, by right atrial pacing and electrograms from the right atrium and coronary sinus were observed for at least five minutes to ensure stable flutter in both atria. Atrial flutter was terminated by 2.5 s or 5 s bursts of atrial pacing at rates 10, 50, or 100 beats/min faster than the intrinsic flutter rate in only two patients. Atrial flutter, which was reinitiated in two patients, was then treated with intravenous disopyramide phosphate, 2 mg/kg body weight, infused over five minutes. In all 10 patients the atrial rate slowed from a mean of 310 +/- 39 beats/min to 217 +/- 27 beats/min and atrial flutter terminated in one case. Though the mean ventricular rate fell from 161 +/- 52 beats/min to 156 +/- 45 beats/min the atrioventricular conduction ratio fell from 2.17 +/- 0.86 to 1.55 +/- 0.59 and four patients were left with symptomatically significant increases of ventricular rate. In seven of nine patients overdrive atrial pacing, repeated after disopryamide, resulted in the conversion of atrial flutter to sinus rhythm. In this study, overdrive atrial pacing and intravenous disopyramide, singly and in combination, terminated atrial flutter in nine of the 10 patients and it is suggested that this method may provide an effective alternative to direct current cardioversion.