Risk stratification in ST-elevation myocardial infarction is enhanced by combining baseline ST deviation and subsequent ST-segment resolution
- 1University of Alberta, Edmonton, Canada
- 2Duke Clinical Research Institute, Durham, USA
- 3St Michael’s Hospital, Toronto, Canada
- 4Uppsala Clinical Research Centre, Uppsala, Sweden
- 5University Hospital Gasthuisberg, Leuven, Belgium
- Professor P W Armstrong, Canadian VIGOUR Centre, 2–51 Medical Sciences Building, University of Alberta, Edmonton AB Canada T6G 2H7;
- Accepted 14 August 2007
- Published Online First 11 October 2007
Background: The baseline sum of ST deviation (ΣSTD) and ST segment resolution after fibrinolysis for ST-elevation myocardial infarction are prognostically useful.
Objectives: To examine the prognostic impact of ST resolution after fibrinolysis and influence of baseline ST deviation in ASSENT-3.
Methods: ST resolution was determined in 4565 patients at 180 minutes after fibrinolysis. 30-Day and 1-year mortality was assessed in patients with complete (ie, ⩾50%) versus incomplete ST resolution according to absolute baseline ΣSTD.
Results: Patients with complete ST resolution had lower 30-day and 1-year mortality than those with incomplete ST resolution (3.7% vs 7.3%, p<0.001, and 6.1% vs 10.0%, p<0.001, respectively). After multivariable adjustment for key baseline risk factors, patients with anterior myocardial infarction (MI) in the highest quartile of ΣSTD had a greater risk of 30-day and 1-year mortality than those in the lowest quartile in both complete (odds ratio (OR) = 2.34, 95% CI 1.14 to 4.80, and OR = 2.34, 95% CI 1.26 to 4.34, respectively) and incomplete ST resolution groups (OR = 4.97, 95% CI 1.82 to 13.61, and OR = 3.61, 95% CI 1.55 to 8.4, respectively). However, in patients with inferior MI this pattern only existed when ST resolution was incomplete (OR = 4.88, 95% CI 1.65 to 14.39, and OR = 4.34, 95% CI 1.66 to 11.37, respectively).
Conclusion: These findings indicate that percentage ST resolution alone is an incomplete guide to 30-day and 1-year mortality. The integration of both the baseline and post-fibrinolysis ECG provides better risk assessment and can assist in the triage and treatment of such patients.
Funding: Boehringer-Ingelheim, Germany, Genentech, South San Francisco, CA, USA, Aventis, Bridgewater, NJ, USA.
Competing interests: None.
Ethics approval: Obtained.