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Flashcards in Thrombus and Embolism Deck (12):
1

Thrombus

is a solid mass formed from the constituents of blood within the vessels or heart during life.

2

Virchow’s Triad-

• Changes in Vascular Wall (Endothelial damage) –
• Changes in Blood Flow (Slow or turbulent flow)
• Changes in Blood (Hypercoagulability)

3

INR

Meadure PT and Extrinsic pathway

4

Outcomes:

• Resolution – Dissolved
• Propagation – Grows
• Organisation – Fibrous Repair , scar
• Recanalisation – New channel through the occlusive thrombus = smaller capacity in new vessel
• Embolization – Breaks off and circulates.

5

Clinical Effects

• Occlusion of artery = ischaemia and infraction
• Embolism distant to site of thrombus
• Congestion and oedema in venous bed
• Repeated miscarriages due to Uteroplacental Vasculature = Inherited thrombophilia’s

6

Embolism

A solid, liquid or gas carried by blood that impacts vascular lumen.

7

Pulmonary emboli arise

80 % source of pulmonary = Deep veins of Thigh , popliteal vein

8

Saddle Emboli-

before the bifurcation of artery thus blocking both branches. Mostly in pulmonary artery.

9

Thromboemboli in arteries

L heart, Aneurysms and thrombi on ulcerated atherosclerosis. They go to lower body, brain, intestines , kidneys, spleen and arms.

10

In left heart:

• Infracts commonly left. Thrombi can then form on the affected necrotic endothelium in Ventricular Cavity. Heart beat = embolism
• Atrial Fibrillation = decreased contraction. Dilation of Left atrium. Stagnation of blood.
• Vegetations more common

11

Paradoxical Emboli

Form in veins but embolise to arteries. They bypass lungs by :
• Small emboli are able to pass through arterio- venous anastomoses in pulmonary circulation
• Larger by Interventricular defects in septum or a patent foramen ovale during coughing , lifting or straining. (pressure in R heart greater than left)
Stroke = more likely to have Patent Foramen Ovale.

12

Emboli From Atheroma

Atheroma = necrotic material from atherosclerotic plaques. Released when plaque raptures. Happen during surgery or catheterisation. Transient Ischaemic Attacks (TIAs) = episodes of neurological dysfunction appear suddenly for minutes to hours. Results of microscopic atheroemboli from carotid artery or left heart. They break up over timedue to size.