In order to more objectively and quantitatively characterize<unk>  on a coronary angiogram, Dr. C. Michael Gibson of the TIMI study group developed and popularized the following<unk>  grading system:
No cineangiographic characteristics of<unk>  present.
Hazy, possible<unk>  present. Angiography demonstrates characteristics such as reduced contrast density, haziness, irregular lesion contour, or a smooth convex "meniscus" at the site of total occlusion suggestive but not diagnostic of<unk> .<unk>  present – small size: Definite<unk>  with greatest dimensions less than or equal to 1/2 vessel diameter.<unk>  present – moderate size: Definite<unk>  but with greatest linear dimension greater than 1/2 but less than 2 vessel diameters.<unk>  present – large size: As in Grade 3 but with the largest dimension greater than or equal to 2 vessel diameters.
Recent total occlusion, can involve some collateralization but usually does not involve extensive collateralization, tends to have a “beak” shape and a hazy edge or appearance of distinct<unk> .
Chronic total occlusion, usually involving extensive collateralization, tends to have distinct, blunt cut-off/edge and will generally clot up to the nearest proximal side branch.
TIMI thrombus grade
TIMI flow grade
TIMI myocardial perfusion grade
TIMI risk score
TIMI bleeding criteria
TIMI frame count 
QRS axis and voltage
Deep vein thrombosis marder score