title: Cigarette smoking and the risk of supraventricular and ventricular tachyarrhythmias in high-risk cardiac patients with implantable cardioverter defibrillators.
abstract: BACKGROUND
  Nicotine elevates serum catecholamine concentration and is therefore potentially arrhythmogenic. However, the effect of cigarette smoking on arrhythmic risk in coronary heart disease patients is not well established.
  
  
  RESULTS
  The risk of appropriate and inappropriate defibrillator therapy by smoking status was analyzed in 717 patients who received an implantable cardioverter defibrillator (ICD) in the Multicenter Automatic Defibrillator Implantation Trial-II. Compared with patients who had quit smoking before study entry (past smokers) and patients who had never smoked (never smokers), patients who continued smoking (current smokers) were significantly younger and generally had more favorable baseline clinical characteristics. Despite this, the adjusted hazard ratio (HR) for appropriate ICD therapy for fast ventricular tachycardia (at heart rates >or=180 b.p.m) or ventricular fibrillation was highest among current smokers (HR = 2.11 [95% CI 1.11-3.99]) and intermediate among past smokers (HR = 1.57 [95% CI 0.95-2.58]), as compared with never smokers (P for trend = 0.02). Current smokers also exhibited a higher risk of inappropriate ICD shocks (HR = 2.93 [95% CI 1.30-6.63]) than past (HR = 1.91 [95% CI 0.97-3.77]) and never smokers (P for trend = 0.008).
  
  
  CONCLUSIONS
  In patients with ischemic left ventricular dysfunction, continued cigarette smoking is associated with a significant increase in the risk of life-threatening ventricular tachyarrhythmias and inappropriate ICD shocks induced by rapid supraventricular arrhythmias. Our findings stress the importance of complete smoking cessation in this high-risk population.
authors.affiliation: Cardiology Unit of the Department of Medicine, University of Rochester Medical Center, Rochester, New York 14642, USA. Ilan.Goldenberg@heart.rochester.edu
authors.forename: Ilan
authors.initials: I
authors.lastname: Goldenberg
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Moss
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zareba
authors.forename: James P
authors.initials: JP
authors.lastname: Daubert
authors.forename: W Jackson
authors.initials: WJ
authors.lastname: Hall
authors.forename: Mark L
authors.initials: ML
authors.lastname: Andrews
mesh_terms: D000368:Aged; D017147:Defibrillators, Implantable; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D016540:Smoking Cessation; D017180:Tachycardia, Ventricular / Q000453:epidemiology / Q000209:etiology / Q000628:therapy*; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000453:epidemiology / Q000628:therapy