The quality of collateral blood supply in @entity66 is pivotal for the resulting hemodynamic compromise. However, the interrelation between different patterns of collateral blood flow and @entity73 of cerebral autoregulation (CAR) has not been analyzed so far. Dynamic CAR was assessed noninvasively by the phase shift between respiratory-induced 0.1-Hz oscillations of arterial blood pressure (ABP) and cerebral blood flow velocity (CBFV) in 101 @entity1 with severe @entity543 (> or = 75%) or @entity432 . @entity515 -vasomotor reactivity was assessed via inhalation of 7% @entity515 . Spontaneously activated collaterals via primary (anterior/posterior communicating artery, type I, n = 65) and secondary (ophthalmic artery / leptomeningeal with or without primary pathways, group II, n = 24) pathways were assessed by transcranial Doppler/duplex sonography. Signs of functional @entity850 in the anterior collateral pathways were subsumed under type III (n = 12). Best dynamic CAR (phase shift) on affected sides was observed for type I (n = 65), in which values did not differ significantly from contralateral sides. Reduced phase shift values were present in type II; poorest values were observed for type III. @entity515 -reactivity differed mainly between type I and the other types. A less distinct differentiation of autoregulatory impairment was found when dividing @entity1 into groups of different degrees of @entity850 . Symptomatic @entity1 (previous TIA/ @entity64 ) were significantly less frequent in the group with type I collateral flow and had significantly lower phase shift and @entity515 -reactivity values. In conclusion, we found that dynamic CAR is substantially impaired if secondary collateral pathways are activated or if functional @entity850 in the activated anterior collateral pathway is present. These hemodynamic constellations are also associated with a higher proportion of clinically symptomatic @entity1 . Determination of dynamic CAR by transfer function analysis represents a convenient, sensitive method for detection of cerebral hemodynamic compromise in obstructive @entity66 .

Dynamic cerebral autoregulation and collateral flow patterns in XXXX with severe @entity543 or @entity432 .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity64 :: ('MESH:D020521', 'Disease') :: ['stroke'] @entity66 :: ('MESH:D004194', 'Disease') :: ['carotid disease'] @entity73 :: ('MESH:D003072', 'Disease') :: ['actual impairment'] @entity515 :: ('CHEBI:29334', 'Chemical') :: ['CO(2)'] @entity432 :: ('MESH:D001157', 'Disease') :: ['occlusion'] @entity850 :: ('MESH:D003251', 'Disease') :: ['stenosis'] @entity543 :: ('MESH:D016893', 'Disease') :: ['unilateral carotid stenosis']
@entity1 :: (9606,Species) :: ['patients']
