Coronary artery thrombus

Coronary Angiography
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Anatomy & Projection Angles
Normal Anatomy Coronary arteries Dominance Right System Left System Left Main Left Anterior Descending Circumflex Median Ramus
Anatomic Variants Separate Ostia Anomalous Origins Case Example Fistula
Projection Angles Standard Views Left Coronary Artery Right Coronary Artery
Epicardial Flow & Myocardial Perfusion
Epicardial Flow TIMI Frame Count TIMI Flow Grade TIMI Grade 0 Flow TIMI Grade 1 Flow TIMI Grade 2 Flow TIMI Grade 3 Flow TIMI Grade 4 Flow Pulsatile Flow Deceleration
Myocardial Perfusion TIMI Myocardial Perfusion Grade TMP Grade 0 TMP Grade 0.5 TMP Grade 1 TMP Grade 2 TMP Grade 3
Lesion Complexity
ACC/AHA Lesion-Specific Classification of the Primary Target Stenosis
Preprocedural Lesion Morphology Eccentricity Irregularity Ulceration Intimal Flap Aneurysm Sawtooth Pattern Length Ostial location Angulation Proximal tortuosity Degenerated SVG Calcification Total occlusion Coronary Artery Thrombus TIMI Thrombus Grade TIMI Thrombus Grade 0 TIMI Thrombus Grade 1 TIMI Thrombus Grade 2 TIMI Thrombus Grade 3 TIMI Thrombus Grade 4 TIMI Thrombus Grade 5 TIMI Thrombus Grade 6
Lesion Morphology Quantitative Coronary Angiography Definitions of Preprocedural Lesion Morphology Irregular Lesion Disease Extent Arterial Foreshortening Infarct Related Artery Restenosis Degenerated SVG Collaterals Aneurysm Bifurcation Trifurcation Ulceration
Left ventriculography
Technique Quantification of LV Function Quantification of Mitral Regurgitation

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: ; Vanessa Cherniauskas, M.D. [2]

Synonyms and keywords: Coronary thrombosis; coronary thrombus

Overview

The Thrombus of coronary arteries occurs when the lumen, of the artery starts becoming smaller and creates a narrowed segment in which the blood flow clots slowly in the artery. This phenomenum in coronary artery decreases the perfusion and may cause necrosis which may lead to a heart attack if not treated.

Definition

The coronary artery thrombus may be defined as an occlusion or blockage of blood flow within a vessel due to a clot.

Pathophysiology

The pathogenic process of arterial thrombosis involves the formation of platelet-rich “white clots” after the rupture of atherosclerotic plaques and exposure of procoagulant material such as lipid-rich macrophages (foam cells), collagen, tissue factor, and/or endothelial breach, in a high shear environment. The exposed material come from within the plaque and also from the activation and aggregation of platelets. Platelet accumulation and fibrin deposition cause an occlusive platelet-rich intravascular thrombus. The growing thrombus increases the degree of narrowing, which may result in extremely high shear rates within the stenotic region. This phenomenum is responsible for a turbulent flow which is developed downstream of the stenosis depending on stenosis geometry and location in the vasculature.

Clinical Significance

• The location of the thrombosis is clinically relevant once the infarction may be subclinical or not.
• Coronary thrombosis may be a complication related to drug-eluting stents.

TIMI Thrombus Grade

TIMI Thrombus Grade 0

• No cineangiographic characteristics of thrombus present.

TIMI Thrombus Grade 1

• Hazy, possible thrombus 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 thrombus.

TIMI Thrombus Grade 2

• Thrombus present – small size
• Definite thrombus with greatest dimensions less than or equal to ½ vessel diameter.

TIMI Thrombus Grade 3

• Thrombus present – moderate size
• Definite thrombus but with greatest linear dimension greater than ½ but less than 2 vessel diameters.

TIMI Thrombus Grade 4

• Thrombus present – large size
• As in Grade 3 but with the largest dimension greater than or equal to 2 vessel diameters.

TIMI Thrombus Grade 5

• Recent total occlusion, can involve some collateralization but usually does not involve extensive collateralization.
• The clot has not propagated backward to the most distal branch and there is often a beak-like appearance of the occlusion.

TIMI Thrombus Grade 6

• 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.

Examples