title: Association between preinfarction angina and a lower risk of right ventricular infarction.
abstract: BACKGROUND
  Right ventricular infarction occurs in conjunction with inferior myocardial infarction caused by proximal occlusion of the right coronary artery. However, right ventricular infarction occurs infrequently, and the reasons for this are uncertain.
  
  
  METHODS
  We retrospectively assessed the association between preinfarction angina and right ventricular infarction, as well as the short-term outcome, in 113 patients with a first acute inferior myocardial infarction caused by right-coronary-artery occlusion. The association between the timing of angina during the week before infarction and the clinical outcome was also assessed.
  
  
  RESULTS
  The absence of preinfarction angina predicted the development of right ventricular infarction (odds ratio, 6.3; 95 percent confidence interval, 2.7 to 15.1; P<0.001), complete atrioventricular block (odds ratio, 3.6; 95 percent confidence interval, 1.4 to 10.3; P=0.01), and combined hypotension and shock (odds ratio, 12.4; 95 percent confidence interval, 4.5 to 40.6; P<0.001). Angina 24 to 72 hours before infarction was most strongly associated with reductions in the rates of right ventricular infarction (adjusted odds ratio, 0.2; 95 percent confidence interval, 0 to 0.8; P=0.02) and combined hypotension and shock (adjusted odds ratio, 0.1; 95 percent confidence interval, 0 to 0.5; P=0.02).
  
  
  CONCLUSIONS
  Preinfarction angina was an independent predictor of the absence of right ventricular infarction in patients with acute inferior myocardial infarction. The patients with preinfarction angina also had better short-term outcomes than those without preinfarction angina.
authors.affiliation: Department of Cardiology, Yokohama Municipal Hospital, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shiraki
authors.forename: T
authors.initials: T
authors.lastname: Yoshikawa
authors.forename: T
authors.initials: T
authors.lastname: Anzai
authors.forename: K
authors.initials: K
authors.lastname: Negishi
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: Y
authors.initials: Y
authors.lastname: Asakura
authors.forename: M
authors.initials: M
authors.lastname: Akaishi
authors.forename: H
authors.initials: H
authors.lastname: Mitamura
authors.forename: S
authors.initials: S
authors.lastname: Ogawa
mesh_terms: D000787:Angina Pectoris / Q000150:complications*; D004562:Electrocardiography; D005260:Female; D006327:Heart Block / Q000209:etiology; D006439:Hemodynamics; D006801:Humans; D007022:Hypotension / Q000209:etiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D011379:Prognosis; D012189:Retrospective Studies; D012769:Shock / Q000209:etiology; D014463:Ultrasonography