Table 1.

Definition of epicardial coronary perfusion by TIMI Flow Grade.

TIMI Flow Grade
TFG 0	Absence of antegrade flow beyond the point of occlusion.
TFG 1	The contrast passes beyond the occlusion but fails to opacify the entire coronary bed distal to the obstruction.
TFG 2	The contrast passes beyond the occlusion but fails to opacify the entire coronary bed distal to the obstruction, but the rate of its entry or clearance is significantly slower than comparable areas not perfused by the previously occluded vessel (e.g., another coronary artery).
TFG 3	Antegrade flow into the bed distal to the obstruction occurs as promptly as antegrade flow into the bed proximal to the obstruction, and clearance of contrast material from the involved bed is as rapid as clearance from an uninvolved bed in the same vessel or in the opposite artery.