title: Thrombolysis and Q wave versus non-Q wave first acute myocardial infarction: a GUSTO-I substudy. Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Arteries Investigators.
abstract: OBJECTIVE
  We assessed the outcomes of patients with a first myocardial infarction with ST segment elevation, with and without the development of abnormal Q waves after thrombolysis.
  
  
  BACKGROUND
  Prethrombolytic era studies report conflicting short-versus long-term mortality in the overall non-Q wave population, probably related to its heterogeneity.
  
  
  METHODS
  Patients with no electrocardiographic (ECG) confounding factors or evidence of previous infarction were included. Q wave infarction was defined as a Q wave duration > or = 30 ms in lead aVF; R wave > or = 40 ms in lead V1; any Q wave or R wave < or = 10 ms and < or = 0.1 mV in lead V2; or Q wave > or = 40 ms in at least two of the following leads: I, aVL, V4, V5 or V6. In-hospital clinical events and mortality at 30 days and 1 year were assessed.
  
  
  RESULTS
  No Q waves developed in 4,601 (21.3%) of the 21,570 patients. This group comprised more women and had a lower Killip class, lower weight and less anterior baseline ST elevation. The non-Q wave group had less in-hospital cardiogenic shock (2.1% vs. 3.3%, p < 0.0001), less heart failure (8.5% vs. 13.9%, p < 0.0001) and a trend toward less stroke (0.7% vs. 1.0%, p = 0.07) but an increased use of angioplasty (28% vs. 24%, p = 0.0001). The unadjusted mortality rate in the non-Q wave group was lower at 30 days (0.9% vs. 1.8%, p = 0.0001) and 1 year (2.7% vs. 4.2%, p = 0.0001), as was the adjusted 30-day mortality rate (4.8% vs. 5.3%, p < 0.0001).
  
  
  CONCLUSIONS
  Patients with no ECG confounding factors or evidence of previous infarction who do not develop Q waves after thrombolysis have a better 30-day and 1-year prognosis than patients with a Q wave infarction.
authors.affiliation: Favaloro Foundation, Buenos Aires, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Barbagelata
authors.forename: R M
authors.initials: RM
authors.lastname: Califf
authors.forename: E B
authors.initials: EB
authors.lastname: Sgarbossa
authors.forename: S G
authors.initials: SG
authors.lastname: Goodman
authors.forename: A L
authors.initials: AL
authors.lastname: Stebbins
authors.forename: C B
authors.initials: CB
authors.lastname: Granger
authors.forename: L D
authors.initials: LD
authors.lastname: Suarez
authors.forename: M
authors.initials: M
authors.lastname: Borruel
authors.forename: K
authors.initials: K
authors.lastname: Gates
authors.forename: S
authors.initials: S
authors.lastname: Starr
authors.forename: G S
authors.initials: GS
authors.lastname: Wagner
mesh_terms: D000368:Aged; D002986:Clinical Trials as Topic; D004562:Electrocardiography; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006329:Heart Conduction System; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology*; D010960:Plasminogen Activators / Q000627:therapeutic use*; D013300:Streptokinase / Q000627:therapeutic use*; D016019:Survival Analysis; D015912:Thrombolytic Therapy; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D013300:Streptokinase; D010960:Plasminogen Activators; D010959:Tissue Plasminogen Activator