Carotid angioplasty in a pulsatile flow model: factors affecting embolic potential.
OBJECTIVE
Carotid endoluminal intervention is an alternative to surgery but carries a risk of embolic stroke even with distal protection devices. We investigated the clinical features and degree of stenosis related to number and size of emboli during carotid angioplasty.


METHODS
An experimental ex vivo study.


METHODS
An ex vivo pulsatile flow model was used in which temperature, velocity, flow, pressure and viscosity characteristics were designed to simulate the carotid circulation.


METHODS
Carotid endarterectomy specimens excised as intact cylinders (n = 28) were subjected to a standardised angioplasty procedure using radiological guidance. Emboli collected in filters placed distally were counted and sized using microscopy.


RESULTS
Median number of emboli during angioplasty was 133 (range 15-1331). Median size of the largest embolus was 700 microns (range 75-2400). Severity of stenosis correlated with increased maximum size (r = 0.55, p = 0.012). Statin therapy >4 weeks pre-operatively was associated with reduced emboli number and size (54 (range 15-748) vs 247 (range 37-1331) [p = 0.023] and 400 microm (range 75-2400) vs 1300 microm (range 600-2200) [p = 0.022]).


CONCLUSIONS
In this model a wide range of emboli number and size were produced. Number and size of embolic particles were highest in patients with high-grade stenoses not receiving statin therapy.
Bicknell
C D
CD
Clinical Pharmacology Department, Imperial College, London, UK.
Cowling
M G
MG
Clark
M W
MW
Delis
K T
KT
Jenkins
M P
MP
Hughes
A D
AD
Thom
S A
SA
Wolfe
J H
JH
Cheshire
N J
NJ
D000368:Aged; D000369:Aged, 80 and over; D016893:Carotid Stenosis / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D004617:Embolism / Q000209:etiology* / Q000503:physiopathology; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D005260:Female; D018056:Hemorheology; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D011673:Pulsatile Flow; D013696:Temperature