Analysis of thrombi retrieved from cerebral arteries of patients with acute ischemic stroke.
OBJECTIVE
Information regarding the histological structure of thromboemboli that cause acute stroke provides insight into pathogenesis and clinical management.


METHODS
This report describes the histological analysis of thromboemboli retrieved by endovascular mechanical extraction from the middle cerebral artery (MCA) and intracranial carotid artery (ICA) of 25 patients with acute ischemic stroke.


RESULTS
The large majority (75%) of thromboemboli shared architectural features of random fibrin:platelet deposits interspersed with linear collections of nucleated cells (monocytes and neutrophils) and confined erythrocyte-rich regions. This histology was prevalent with both cardioembolic and atherosclerotic sources of embolism. "Red" clots composed uniquely of erythrocytes were uncommon and observed only with incomplete extractions, and cholesterol crystals were notably absent. The histology of thromboemboli that could not be retrieved from 29 concurrent patients may be different. No thrombus >3 mm wide caused stroke limited to the MCA, and no thrombus >5 mm wide was removed from the ICA. A mycotic embolus was successfully removed in 1 case, and a small atheroma and attached intima were removed without clinical consequence from another.


CONCLUSIONS
Thromboemboli retrieved from the MCA or intracranial ICA of patients with acute ischemic stroke have similar histological components, whether derived from cardiac or arterial sources. Embolus size determines ultimate destination, those >5 mm wide likely bypassing the cerebral vessels entirely. The fibrin:platelet pattern that dominates thromboembolic structure provides a foundation for both antiplatelet and anticoagulant treatment strategies in stroke prevention.
Marder
Victor J
VJ
Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles Orthopaedic Hospital, 2400 S Flower St, Los Angeles, California 90007, USA. vmarder@laoh.ucla.edu
Chute
Dennis J
DJ
Starkman
Sidney
S
Abolian
Anna M
AM
Kidwell
Chelsea
C
Liebeskind
David
D
Ovbiagele
Bruce
B
Vinuela
Fernando
F
Duckwiler
Gary
G
Jahan
Reza
R
Vespa
Paul M
PM
Selco
Scott
S
Rajajee
Venkatakrishna
V
Kim
Doojin
D
Sanossian
Nerses
N
Saver
Jeffrey L
JL
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002343:Carotid Artery, Internal; D017128:Embolectomy; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D007275:Injections, Intravenous; D002542:Intracranial Embolism and Thrombosis / Q000150:complications* / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery; D020521:Stroke / Q000209:etiology*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage / Q000627:therapeutic use
D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator