title: Proarrhythmic response to antiarrhythmic drug as a risk factor for sudden cardiac death in patients with ischemic heart disease.
abstract: The prognostic significance of arrhythmogenic response to an antiarrhythmic drug was studied. In 782 patients with ischemic heart disease (IHD) and frequent and/or complex ventricular premature beats (VPBs), 1,041 drug tests guided by 24-hour Holter monitoring were conducted. The following drugs were assessed: beta blockers, disopyramide, mexiletine, amiodarone. Proarrhythmia was defined as: (1) greater than 4-fold increase in VPBs, (2) greater than 10-fold increase in repetitive forms, or (3) new occurrence of ventricular tachycardia or ventricular fibrillation (VT/VF). During a follow-up of 1-49 months (mean 22) patients were treated with antiarrhythmic drugs found to be safe in control Holter monitoring. Proarrhythmic effects were observed in 8.4% of patients. No drug was completely free of this type of reaction. In long-term observation, cardiac death and sudden death occurred in 53 and 32 patients, respectively. With actuarial analysis (Kaplan-Meier method, log-rank test) there was a significant difference in cardiac death (P less than 0.01) and sudden death rate (P less than 0.05) of proarrhythmia (+) compared with proarrhythmia (-) patients at 1 year (11% vs 4%, 7% vs 3%) and 3 years (24% vs 11%, 16% vs 7%). Proarrhythmic response was an independent risk factor apart from myocardial infarction, VT/VF, ejection fraction less than 40% and QTc greater than 440 msec. Arrhythmogenic response to antiarrhythmic drugs seems to be an additional predictor of sudden death in IHD.
authors.affiliation: First Cardiologic Clinic, Silesian Medical Academy, Silesian Heart Center, Katowice, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Trusz-Gluza
authors.forename: L
authors.initials: L
authors.lastname: Giec
authors.forename: A
authors.initials: A
authors.lastname: Dabrowski
authors.forename: J
authors.initials: J
authors.lastname: Kuch
authors.forename: S
authors.initials: S
authors.lastname: Pasyk
authors.forename: W
authors.initials: W
authors.lastname: Piwowarska
authors.forename: H
authors.initials: H
authors.lastname: Pracka
authors.forename: Z
authors.initials: Z
authors.lastname: Sadowski
authors.forename: J
authors.initials: J
authors.lastname: Wodniecki
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000139:chemically induced*; D005117:Cardiac Complexes, Premature / Q000188:drug therapy*; D003327:Coronary Disease / Q000150:complications*; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D016019:Survival Analysis
chemical_list: D000889:Anti-Arrhythmia Agents