Computer-assisted myocardial blush quantification after percutaneous coronary angioplasty for acute myocardial infarction: a substudy from the TAPAS trial.
AIMS
Myocardial reperfusion after acute myocardial infarction can be angiographically assessed by the myocardial blush grade (MBG) or TIMI Perfusion Grade. These scores are based on subjective human judgement and lead to a score of four categories. A more operator-independent way of scoring myocardial perfusion may facilitate research in this area.


METHODS AND RESULTS
We designed the 'Quantitative Blush Evaluator' (QuBE), a computer program which calculates a score for myocardial perfusion. This program will be freely available as open source software. The inter-observer concordance was 97.7%. We calculated values on prospectively collected angiograms in patients with acute ST-elevation myocardial infarction from the TAPAS trial. Quantitative blush evaluator values could be assessed on 790 out of 980 collected angiograms (81%). The QuBE score correlated significantly with MBG as determined by a core lab. The QuBE score predicted complete ST-elevation resolution, low enzyme levels, and 1 year survival (all P < 0.001). Quantitative blush evaluator value was an independent predictor of mortality at 1 year [OR 0.40 (0.17-0.90), P = 0.02].


CONCLUSION
The QuBE program provides a practical, freely available computer-assisted assessment of myocardial perfusion. The QuBE score provides a useful surrogate endpoint in trials of therapies aimed at improving myocardial reperfusion.