title: Intolerance and ineffectiveness of mexiletine in patients with serious ventricular arrhythmias.
abstract: Fifty-one patients were treated with mexiletine over 10.4 +/- 16 months. The clinical arrhythmia in 25 (49%) was ventricular fibrillation (VF), 11 (22%) had sustained ventricular tachycardia (VT), and 15 (29%) had symptomatic nonsustained VT. Ischemic heart disease was present in 33 patients (66%), cardiomyopathy in nine (17%), and valvular or congenital heart disease in nine (17%). Only six (12%) remain on the drug. Arrhythmias recurred in 21 patients (41%): seven (14%) with VF, three (5%) with sustained VT, and 11 (22%) with symptomatic nonsustained VT. Intolerable side effects occurred in another 17 (33%). Seven patients (14%) died from nonarrhythmic-related deaths while taking mexiletine. Mexiletine was combined with a conventional type IA antiarrhythmic agent in 25 patients (49%). In 12 of these 25 patients (48%), ventricular arrhythmias recurred. These findings were not significantly different from those of the group treated with mexiletine alone, where arrhythmias recurred in 9 of 26 patients (35%) (p = NS). Thus mexiletine, alone or in combination with a type IA antiarrhythmic agent, has limited clinical utility in patients with life-threatening ventricular arrhythmias.
mesh_terms: D002304:Cardiac Pacing, Artificial; D004206:Disopyramide / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D004562:Electrocardiography; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008801:Mexiletine / Q000009:adverse effects* / Q000627:therapeutic use; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009325:Nausea / Q000139:chemically induced; D011342:Procainamide / Q000627:therapeutic use; D011437:Propylamines / Q000009:adverse effects*; D011802:Quinidine / Q000627:therapeutic use; D012008:Recurrence; D013610:Tachycardia / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality; D014202:Tremor / Q000139:chemically induced; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality
chemical_list: D011437:Propylamines; D008801:Mexiletine; D004206:Disopyramide; D011802:Quinidine; D011342:Procainamide