title: Distortion of the QRS in elderly patients with myocardial infarction.
abstract: BACKGROUND
  Distortion of the terminal portion of the QRS in the initial electrocardiogram (ECG) is a strong predictor of adverse outcome in myocardial infarction. Our purpose is to assess the relationship of distortion of QRS and other ECG characteristics with older age.
  
  
  RESULTS
  We analysed 634 consecutive patients (age 62.6 +/- 13.7, 77% male) admitted in the first 12 hours of ST-elevation myocardial infarction. Two groups of age were defined: < 75 years-old and >or= 75 years-old. Additionally, we defined two ECG groups according to the presence of ST segment elevation with distortion of the terminal portion of the QRS in two or more adjacent leads (QRS+) or the absence of this pattern (QRS-). Older people had more often QRS+ (30% vs. 20%, p = 0.023). The older group with QRS+ had an in-hospital mortality of 18%, vs. 7% with QRS- (p = 0.04), and an incidence of major adverse events of 40% vs. 14% (p = 0.002). In the multivariate analysis, age >or= 75 years was an independent predictor of distortion of the QRS (odds ratio 2.1, 1.2-4.9, p = 0.016).
  
  
  CONCLUSIONS
  The distortion of the terminal portion of the QRS in myocardial infarction is more frequent in elderly people, and is significantly related to adverse prognosis. This ECG finding can be helpful to promptly stratify the risk in elderly patients.
authors.affiliation: Cardiovascular Institute, Hospital Clinico San Carlos, Madrid, Spain. grubira@wanadoo.es
authors.forename: Juan C
authors.initials: JC
authors.lastname: García-Rubira
authors.forename: Iván
authors.initials: I
authors.lastname: Núnez-Gil
authors.forename: Rafael
authors.initials: R
authors.lastname: García-Borbolla
authors.forename: Vera
authors.initials: V
authors.lastname: Lennie
authors.forename: María C
authors.initials: MC
authors.lastname: Manzano
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Cobos
authors.forename: Leopoldo Pérez
authors.initials: LP
authors.lastname: de Isla
authors.forename: Antonio
authors.initials: A
authors.lastname: Fernández-Ortiz
authors.forename: Carlos
authors.initials: C
authors.lastname: Macaya
mesh_terms: D000367:Age Factors; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D016017:Odds Ratio; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012307:Risk Factors; D012770:Shock, Cardiogenic / Q000209:etiology / Q000401:mortality / Q000503:physiopathology; D015912:Thrombolytic Therapy; D013997:Time Factors; D016896:Treatment Outcome