TIMI grade flow - grading of coronary blood flow during coronary angiography

This TIMI classification was developed by the TIMI (Thrombolysis In Myocardial Infarction) study group to semiquantitatively assess coronary artery perfusion beyond point of occlusion on coronary angiography.

TIMI Grade Description
TIMI 0 - no perfusion no antegrade flow beyond the point of occlusion
TIMI 1 - penetration without perfusion faint antegrade coronary flow beyond the occlusion with incomplete filling of the distal coronary bed
TIMI 2 - partial perfusion delayed or sluggish antegrade flow with complete filling of the distal territory
TIMI 3 - complete perfusion normal flow with complete filling of the distal territory

PAMI (Primary Angioplasty in Myocardial Infarction) investigators precised the description of TIMI 3 as "opacification of the vessel within three cardiac cycles).


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