Bossaert et al evaluated reperfusion after thrombolytic therapy by comparing the total sum of ST-segment elevation in all leads before and after thrombolytic therapy. The authors are from the University of Antwerp in Belgium.


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.


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