Prognostic implications of quantitative evaluation of baseline Q-wave width in ST-segment elevation myocardial infarction.
OBJECTIVE
To evaluate quantitative relationships between baseline Q-wave width and 90-day outcomes in ST-segment elevation myocardial infarction (STEMI).


BACKGROUND
Baseline Q-waves are useful in predicting clinical outcomes after MI.


METHODS
3589 STEMI patients were assessed from a multi-centre study.


RESULTS
1156 patients of the overall cohort had pathologic Q-waves. The 90-day mortality and the composite of mortality, congestive heart failure (CHF), or cardiogenic shock (p<0.001 for both outcomes) rose as Q-wave width increased. After adapting a threshold ≥40ms for inferior and ≥20ms for lateral/apical MI in all patients (n=3065) with any measureable Q-wave we found hazard ratios (HR) for mortality (HR: 2.44, 95% confidence interval (CI) (1.54-3.85), p<0.001) and the composite (HR: 2.32, 95% CI (1.70-3.16), p<0.001). This improved reclassification of patients experiencing the composite endpoint versus the conventional definition (net reclassification index (NRI): 0.23, 95% CI (0.09-0.36), p<0.001) and universal MI definition (NRI: 0.15, 95% CI (0.02-0.29), p=0.027).


CONCLUSIONS
The width of the baseline Q-wave in STEMI adds prognostic value in predicting 90-day clinical outcomes. A threshold of ≥40ms in inferior and ≥20ms for lateral/apical MI enhances prognostic insight beyond current criteria.
Canadian VIGOUR Centre, University of Alberta, Edmonton, AB, Canada.
Mike H
MH
Bao
Canadian VIGOUR Centre, University of Alberta, Edmonton, AB, Canada.
Yinggan
Y
Zheng
Canadian VIGOUR Centre, University of Alberta, Edmonton, AB, Canada.
Cynthia M
CM
Westerhout
Canadian VIGOUR Centre, University of Alberta, Edmonton, AB, Canada.
Yuling
Y
Fu
Duke Clinical Research Institute, Durham, NC, USA.
Galen S
GS
Wagner
Saint Louis University Health Sciences Center, St. Louis, MO, USA.
Bernard
B
Chaitman
Duke Clinical Research Institute, Durham, NC, USA.
Christopher B
CB
Granger
Canadian VIGOUR Centre, University of Alberta, Edmonton, AB, Canada. Electronic address: e.paul.armstrong@ualberta.ca.
Paul W
PW
Armstrong
D000368:Aged; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D015897:Comorbidity; D004311:Double-Blind Method; D004562:Electrocardiography / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006333:Heart Failure / Q000401:mortality*; D006801:Humans; D038622:Internationality; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality*; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012770:Shock, Cardiogenic / Q000401:mortality*; D057127:Single-Chain Antibodies / Q000627:therapeutic use; D015996:Survival Rate
D061067:Antibodies, Monoclonal, Humanized; D057127:Single-Chain Antibodies; C402724:pexelizumab
Electrocardiogram; Prognosis; Q-wave; STEMI; Width