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).
References:
1. The Thrombolysis in Myocardial Infarction (TIMI) trial. Phase I findings. TIMI Study Group. N. Engl. J. Med. 1985 Apr 4;312(14):932–6.
2. Chesebro JH, Knatterud G, Roberts R, Borer J, Cohen LS, Dalen J, et al. Thrombolysis in Myocardial Infarction (TIMI) Trial, Phase I: A comparison between intravenous tissue plasminogen activator and intravenous streptokinase. Clinical findings through hospital discharge. Circulation. 1987 Jul 1;76(1):142–54.
3. Comparison of Invasive and Conservative Strategies after Treatment with Intravenous Tissue Plasminogen Activator in Acute Myocardial Infarction. New England Journal of Medicine. 1989;320(10):618–27.
4. Kern MJ, Moore JA, Aguirre FV, Bach RG, Caracciolo EA, Wolford T, et al. Determination of Angiographic (TIMI Grade) Blood Flow by Intracoronary Doppler Flow Velocity During Acute Myocardial Infarction. Circulation. 1996 Oct 1;94(7):1545–52.