Abstract

Objectives To examine the prognostic impact of ST resolution after fibrinolysis and influence of baseline ST deviation in ASSENT 3.

Background The baseline sum of ST deviation (∑STD) and ST segment resolution post fibrinolysis for ST elevation myocardial infarction (STEMI) are prognostically useful

Methods ST resolution was determined in 4565 patients at 180 min post fibrinolysis. Thirty day and 1-year mortality was assessed in patients with complete (i.e. ≥50%) vs. incomplete ST resolution according to absolute baseline ∑STD.

Results Patients with complete ST resolution had lower 30-day and 1-year mortality compared to 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, anterior MI patients in the highest quartile of ∑STD had a greater risk of 30-day and 1-year mortality than those in the lowest quartile in both complete (OR 2.34, 95% CI 1.14-4.8, and OR 2.34, 95% CI 1.26-4.34, respectively) and incomplete ST resolution groups (OR 4.97, 95% CI 1.82-13.61, and OR 3.61, 95% CI 1.55-8.4, respectively). However, in inferior MI patients this pattern only existed when ST resolution was incomplete (OR 4.88, 95% CI 1.65-14.39, and OR 4.34, 95% CI 1.66-11.37, respectively).

Conclusion These findings indicate that % 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 superior risk assessment and can assist in the triage and treatment of such patients.