title: Inverse relationship of blood pressure levels to sudden cardiac mortality and benefit of the implantable cardioverter-defibrillator in patients with ischemic left ventricular dysfunction.
abstract: OBJECTIVE
  This study was designed to evaluate the relationship among blood pressure (BP) levels, risk of sudden cardiac death (SCD), and benefit of the implantable cardioverter-defibrillator (ICD) in patients with ischemic left ventricular (LV) dysfunction.
  
  
  BACKGROUND
  Low BP has been shown to be associated with increased mortality in patients with LV dysfunction and heart failure. We hypothesized that increasing BP levels are associated with a reduction in the risk of SCD in this population, thereby limiting ICD efficacy in a lower-risk subset.
  
  
  METHODS
  The independent contribution of systolic blood pressure (SBP) and diastolic blood pressure (DBP) to outcome was analyzed in 1,231 patients enrolled in the prospective MADIT-II (Multicenter Automatic Defibrillator Implantation Trial II).
  
  
  RESULTS
  Multivariate analysis showed that in the conventional therapy arm of the trial, 10-mm Hg increments in systolic BP were independently associated with a respective 14% (p = 0.01) and 16% (p = 0.04) reduction in the risk of cardiac mortality and SCD; similar trends were shown for DBP. Defibrillator therapy provided the least survival benefit to patients in the lower-risk, upper SBP (>130 mm Hg) and DBP (>/=80 mm Hg) quartiles (hazard ratio 1.04 [p = 0.89] and 1.05 [p = 0.88], respectively), whereas a respective 39% and 38% (p = 0.002) reduction in the risk of death with ICD therapy was observed among patients with lower BP values.
  
  
  CONCLUSIONS
  In patients with ischemic LV dysfunction, SBP and DBP levels show an inverse correlation with sudden cardiac mortality. These noninvasive hemodynamic parameters may be useful for identifying lower-risk patients, in whom the benefit of primary defibrillator implantation is more limited.
authors.affiliation: Cardiology Unit of the Department of Medicine, University of Rochester Medical Center, Rochester, New York, 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: W Jackson
authors.initials: WJ
authors.lastname: Hall
authors.forename: Mark L
authors.initials: ML
authors.lastname: Andrews
mesh_terms: D001794:Blood Pressure; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D017147:Defibrillators, Implantable; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications; D018487:Ventricular Dysfunction, Left / Q000209:etiology