THE CORRECT TIMI FRAME COUNT - THE NEW GOLD STANDARD

Over the last decade Thrombolysis in Myocardial Infarction (TIMI) flow grades have been the gold standard for the assessment of efficacy of infarct-artery reperfusion. However, with the introduction of core ang iographic laboratories, the reproducibility of TIMI flow grades has be en questioned. The corrected TIMI frame count (CTFC) has been develope d as a more reproducible method of quantifying infarct artery blood fl ow after myocardial infarction (MI). We have utilised the CTFC in two studies to examine infarct-artery bloodflow. In the Hirulog in Early R eperfusion and Occlusion (HERO 1) study, the CTFC was measured at 90-1 20 minutes after administration of aspirin, streptokinase and either H irulog or heparin. Only 27% of patients had a normal CTFC (less than o r equal to 27) in the infarct-related artery. Patients with a prolonge d CTFC (>27) had more abnormal left ventricular function (LVF) as meas ured by the mean chord score in the 'area at risk' (-2.51 vs -2.06 p=0 .02), on left ventriculography. In a second study, infarct-artery flow was examined four weeks and one year after MI. At four weeks, only 43 % of patients with patent infarct-related arteries had a 'normal' CTFC of less than or equal to 27. A prolonged CTFC at four weeks was a uni variate predictor of increased reocclusion at one year (p=0.001). CTFC s are frequently abnormal in parent infarct-related arteries, and pred ict reocclusion. Whether frame counting is a better predictor of late clinical outcomes than the TIMI flow grade needs to be prospectively e xamined in large clinical trials.