Flecainide: steady state electrophysiologic effects in patients with remote myocardial infarction and inducible sustained ventricular arrhythmia.
The effect of flecainide in 24 patients with inducible sustained ventricular arrhythmia and a history of remote myocardial infarction was determined. Flecainide was administered in oral doses individually adjusted to suppress all spontaneous ventricular tachycardia and 80% of ventricular premature complexes on 24 hour ambulatory (Holter) electrocardiography. Antiarrhythmic therapy, as assessed by Holter monitoring, was adequate in 20 (83%) of the study patients at a mean dose of 144 +/- 28 mg every 12 hours; the mean plasma flecainide level was 583 +/- 329 ng/ml. In 18 patients, the mean sinus cycle length, sinus node recovery time and atrial, atrioventricular nodal and ventricular refractory periods were unchanged. The AH interval increased by 15 +/- 15%, the HV interval by 35 +/- 32% and the QRS duration by 24 +/- 21%. Toxicity or failure to suppress ventricular premature complexes and ventricular tachycardia by Holter monitoring precluded electrophysiologic study with flecainide in four patients; two patients refused electrophysiologic study with flecainide for nonmedical reasons. Ventricular tachycardia was not inducible in 4 (22%) of 18 patients receiving flecainide. Sustained arrhythmia remained inducible in 14 patients (78%) despite evidence of antiarrhythmic efficacy on Holter monitoring, but the rate of the induced ventricular tachycardia was slower and symptoms were alleviated during ventricular tachycardia in 10 (56%) of 18 patients. The 4 patients who had no inducible ventricular tachycardia with flecainide, and the 10 patients who had inducible ventricular tachycardia with a longer cycle length and alleviation of their symptoms, have been followed up as outpatients for 16 +/- 7 months.(ABSTRACT TRUNCATED AT 250 WORDS)
Webb
C R
CR
Morganroth
J
J
Senior
S
S
Spielman
S R
SR
Greenspan
A M
AM
Horowitz
L N
LN
D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D005260:Female; D005424:Flecainide; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009203:Myocardial Infarction / Q000150:complications* / Q000503:physiopathology; D010880:Piperidines / Q000627:therapeutic use*; D013997:Time Factors
D010880:Piperidines; D005424:Flecainide