The measurement of ST segment elevation was done at 20 milliseconds after the end of the QRS complex using a baseline based on the preceding PTa-segment. Depression in the ST-segment was not included. Measurements were in millivolts. Measurements did not need to exceed a threshold value to be included.
total ST-segment elevation in all 12 leads =
= SUM(elevation in the limb and precordial leads)
The coronary artery was considered patent if there was a decrease in the total ST segment elevation by >= 50%.
percent decrease in total ST segment elevation =
= 100% * (1 - ((total ST segment after thrombolysis) / (total ST segment before)))
Alternatively the criteria could be the ratio of the two as <= 50%.
ratio of the total ST segment elevations after to before thrombolysis =
= residual ST segment elevation =
= ((total ST segment after thrombolysis) / (total ST segment before))
Timing of post-thrombolytic ECG: Bossaert monitored the ST segment elevation at 2 hours after thrombolysis, while Mauri et all (GISSI-2) monitored the elevation at 4 hours after thrombolysis.
Patients who show early reperfusion have lower short and long term mortality as well as a better quality of life.
