title: Q wave and Non-Q wave myocardial infarction after thrombolysis.
abstract: OBJECTIVE
  We studied the clinical outcome of Q wave and non-Q wave infarction after thrombolytic therapy.
  
  
  BACKGROUND
  Controversy exists over the clinical significance of Q waves after thrombolysis.
  
  
  METHODS
  We studied postthrombolytic angiographic results and short- and long-term clinical outcome in 150 patients with acute myocardial infarction classified as Q wave and non-Q wave on the 24-h and discharge electrocardiograms (ECGs). The results from the two groups were then compared.
  
  
  RESULTS
  Eighty percent of patients had a Q wave and 20% a non-Q wave infarction on the 24-h ECG. The latter patients had lower peak creatine kinase (CK) levels (p < 0.001), but the two groups did not differ significantly otherwise. In 18 patients with a Q wave infarction on the 24-h ECG, pathologic Q waves disappeared. However, in seven patients with a non-Q wave infarction on the 24-h ECG, pathologic Q waves appeared throughout the hospital period. Q wave regression was associated with lower peak CK levels (p < 0.001) and an improvement in left ventricular ejection fraction (p < 0.01). Thus, only 72% of patients had a Q wave and 28% a non-Q wave infarction on the discharge ECG. Patients with a non-Q wave infarction on the discharge ECG had higher patency of the infarct-related artery (p < 0.04), lower mean peak CK levels (p < 0.0001), a higher ejection fraction (p = 0.001) and a lower incidence of heart failure (p = 0.06) than patients with a Q wave infarction on the discharge ECG. Although the 2-year incidence of reinfarction and revascularization was higher in patients with a non-Q wave infarction on the discharge ECG (p < 0.05), 2-year mortality was lower (p = 0.08).
  
  
  CONCLUSIONS
  Although the early postthrombolytic distinction between Q wave and non-Q wave infarction conveys no significant information, during the hospital period, non-Q wave infarction is associated with a smaller infarct area, improved left ventricular function and lower mortality.
authors.affiliation: Heart Institute, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: S
authors.initials: S
authors.lastname: Matetzky
authors.forename: G I
authors.initials: GI
authors.lastname: Barabash
authors.forename: B
authors.initials: B
authors.lastname: Rabinowitz
authors.forename: S
authors.initials: S
authors.lastname: Rath
authors.forename: Y H
authors.initials: YH
authors.lastname: Zahav
authors.forename: O
authors.initials: O
authors.lastname: Agranat
authors.forename: E
authors.initials: E
authors.lastname: Kaplinsky
authors.forename: H
authors.initials: H
authors.lastname: Hod
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D015635:Radionuclide Ventriculography; D015912:Thrombolytic Therapy; D013997:Time Factors; D016896:Treatment Outcome