title: Distortion of the terminal portion of the QRS is predictor of shock after primary percutaneous coronary intervention for acute myocardial infarction.
abstract: BACKGROUND
  Although invasive management of ST segment elevation myocardial infarction has improved the clinical outcome, cardiogenic shock (CS) remains an important issue. Our purpose was to asses the utility of the initial electrocardiogram in detecting patients who are at increased risk of CS after percutaneous coronary intervention for acute myocardial infarction.
  
  
  METHODS
  We evaluated 508 consecutive patients admitted in our Coronary Unit and treated by primary angioplasty within 12 h of an ST segment elevation myocardial infarction. Patients with cardiogenic shock at admission were excluded. Two groups were defined according to the presence of distortion of the terminal portion of the QRS in two or more adjacent leads (group 1) or the absence of this pattern (group 2).
  
  
  RESULTS
  There were 99 patients (20%) in group 1 and 409 (80%) in group 2. CS developed in 38 patients, 18 in group 1 (18%) and 20 in group 2 (5%), p<0.001. Seventeen patients died in hospital, 6 in group 1 (6%) and 11 in group 2 (3%), p 0.094. Multivariate analysis including clinical, electrocardiographic and angiographic variables showed distortion of the QRS as an independent predictor of cardiogenic shock (odds ratio 3.17, 95% confidence interval 1.44 to 6.96, p 0.004), together with Killip class at admission and TIMI 3 flow after revascularization.
  
  
  CONCLUSIONS
  Distortion of the terminal portion of the QRS complex is a strong predictor of cardiogenic shock in STEMI patients. Close hemodynamic monitoring should be warranted in patients showing this electrocardiographic pattern.
authors: Instituto Cardiovascular, Hospital San Carlos, Madrid, Spain. drchjcgr@arrakis.es
authors: Juan C
authors: JC
authors: Garcia-Rubira
authors: Rafael
authors: R
authors: Garcia-Borbolla
authors: Ivan
authors: I
authors: Nuñez-Gil
authors: Maria C
authors: MC
authors: Manzano
authors: Maria M
authors: MM
authors: Garcia-Romero
authors: Antonio
authors: A
authors: Fernandez-Ortiz
authors: Leopoldo
authors: L
authors: Perez de Isla
authors: Carlos
authors: C
authors: Macaya
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000379:methods* / Q000592:standards; D004562:Electrocardiography / Q000379:methods* / Q000592:standards; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology / Q000628:therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012770:Shock, Cardiogenic / Q000209:etiology* / Q000503:physiopathology*