Hypertrophic remodeling and increased arterial stiffness in patients with intracranial aneurysms.
OBJECTIVE
Because an underlying arteriopathy might contribute to the development of intracranial aneurysms (IAs), we assessed the elastic properties of proximal conduit arteries in patients with IA.


METHODS
In 27 patients with previous ruptured IA and 27 control subjects matched for age, gender and BMI, we determined arterial pressure, internal diameter, intima-media thickness (IMT), circumferential wall stress (CWS) and elastic modulus (wall stiffness) in common carotid arteries using applanation tonometry and echotracking. Moreover, carotid augmentation index (AIx, arterial wave reflections) and carotid-to-femoral pulse wave velocity (PWV, aortic stiffness) were assessed.


RESULTS
Compared with controls, patients with IA exhibited higher brachial and carotid systolic and diastolic blood pressures, with similar brachial but higher carotid artery pulse pressure (35 + or - 6mm Hg vs. 41 + or - 8mm Hg, P=0.014). Moreover, patients have higher PWV (7.8 + or - 1.2ms(-1) vs. 8.3 + or - 1.1ms(-1), P=0.048) and AIx (15.8 + or - 10.8% vs. 21.1 + or - 8.5%, P<0.001) which contributes to increase carotid blood pressures. Furthermore, carotid IMT was higher in patients (546 + or - 64 microm vs. 642 + or - 70 microm, P<0.001) without difference in diameter suggesting an adaptive hypertrophy. However, patients display a lower CWS (61.6 + or - 9.2 kPa vs. 56.9 + or - 10.3 kPa, P=0.007) and no correlation between IMT and pulse pressure (r=0.152, P=NS) in contrast to controls (r=0.539, P<0.001) showing the contribution of a pressure-independent process. Finally, despite this lesser CWS, elastic modulus was increased in patients (310 + or - 105 kPa vs. 383 + or - 174 kPa, P=0.026).


CONCLUSIONS
This study demonstrates that patients with IA display a particular carotid artery phenotype with an exaggerated hypertrophic remodeling and altered elastic properties. Thus, a systemic arteriopathy might contribute, together with the arterial wall fatiguing effect of the increased pulsatile stress, to the pathogenesis of IA.
Maltete
David
D
Department of Neurology, CHU-Hopitaux de Rouen & Institut National de la Sante et de la Recherche Medicale (INSERM) U644, Institut Federatif de Recherche Multidisciplinaire sur les Peptides (IFRMP) 23, Institute for Biomedical Research, University of Rouen, France.
Bellien
Jeremy
J
Cabrejo
Lucie
L
Iacob
Michele
M
Proust
François
F
Mihout
Bruno
B
Thuillez
Christian
C
Guegan-Massardier
Evelyne
E
Joannides
Robinson
R
D000328:Adult; D001158:Arteries / Q000473:pathology*; D002339:Carotid Arteries / Q000473:pathology; D004548:Elasticity; D005260:Female; D005263:Femoral Artery / Q000473:pathology; D006801:Humans; D006984:Hypertrophy / Q000473:pathology*; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011674:Pulse; D013314:Stress, Mechanical; D017539:Tunica Intima / Q000473:pathology; D017540:Tunica Media / Q000473:pathology; D014655:Vascular Resistance