Demographic data: Overall, 72 patients ( age: 69.34±7.56 year, male: 47) were enrolled in the operation group and 47 patients ( age: 64.25±10.83 year, male:27) were enrolled in the control group respectively. And there was no statistical difference between the operation group and the control group in demographic data (age, sex, diabetes mellitus, hypertension, heart disease, current smoker, HbA1c, uric acid, creatinine, obesity). The demographic data in the control and operation groups are shown in Table 1.
CAS: Among the operation patients, 19 patients were diagnosed the carotid artery stenosis in Grade 1 (50-70%), 38 patients in Grade 2 (70-90%) and 15 patients in Grade 3 (>90%) respectively. The changes in carotid artery stenosis before and after CAS are shown in Figure 1.
28 of 72 patients (38.89%) who had occurred the neurological symptom (stroke, transient ischemic attack and amaurosis fugax) before CAS. Besides, 5 of 72 (6.94%) patients occurred the complications (2 TIA, 2 stroke and 1 death) after CAS. And there were no myocardial infarction and hemorrhage at the 30 days follow-up visits after CAS.
TCD: After CAS, the MFV (pre-operation, post-operation, 30 days follow-up: 47.65±17.24, 62.37±18.25, 70.29±16.89; P<0.05 ) and PI (pre-operation, post-operation, 30 days follow-up: 0.78±0.21, 0.98±0.19, 1.02±0.20; P<0.05 ) increased significantly in the ipsilateral MCA. And the CVR improved significantly (post-operation, 30 days follow-up: 27.47±12.13, 31.92±10.94; P<0.05) at 30 days follow-up. For patients with different degrees of carotid artery stenosis, the more severe stenosis in carotid artery, the more obvious improvement of CVR at the 30 days follow-up after CAS. But the CVR had no statistical change at 24 hours after CAS (pre-operation, post-operation: 23.39±10.21, 27.47±12.13; P>0.05). The hemodynamic data in the operative patients is shown in Table 2.
DWI: Although some operative patients had occurred the neurological symptom before CAS, we operated the treatment after the stage of acute cerebral infarction for safety reasons. So the symptomatic patients who performed on MRI before CAS had no hyperintense in DWI images. However, there were 29 patients showed the emerging hyperintense in DWI after CAS. Among the 29 patients with hyperintense in DWI, 5 patients (2 TIA, 2 stroke and 1 death) occurred the ischemic events, and the remaining 24 patients showed the DWI+ rather than neurological deficits.
Biochemical markers: (1) The serum concentrations of GFAP and S100B in the control patients had no significant change after DSA (P > 0.05). (2) After CAS, the serum concentrations of GFAP and S100B increased to the peak at 24 hour after operation (T2), and then decrease gradually. There were the lowest values at the 30 days after CAS (T2>T3>T4; P < 0.05). Furthermore, the serum concentrations of GFAP (r=0.71, P<0.05) and S100B (r=0.78, P<0.05) correlated positively with CVR at 30 days after CAS. The serum concentrations of GFAP and S100B in the patients before and after operation are shown in Table 3 and Figure 2. (3) Among the 5 patients with post-operative symptoms, the serum values of GFAP and S100B in 2 TIA increased temporarily at 24 hours after operation (T2), and then came back to the basal at 30 days after operation (T4). But for the 2 stroke and 1 death patients, the serum GFAP and S100B increased continuously even at the 30 days after CAS. And the fatal patient maintained a higher level than the stroke at any time points during the 1 month follow-up. The details for the 5 patients with post-operative complications are shown in Figure 3.
Table 1 Demographic data in the control and operation patients
|
operation group (n=72)
|
control group (n=47)
|
T or χ2
|
P value
|
Mean±SD age (year)
|
69.34±7.56
|
64.25±10.83
|
-0.359
|
0.78
|
Sex (male)
|
47 (65.28)
|
27 (57.45)
|
1.002
|
0.09
|
Diabetes
|
33 (45.83)
|
10 (21.28)
|
0.358
|
0.07
|
Hypertension
|
51 (70.83)
|
21 (70.00)
|
0.694
|
0.63
|
Heart disease
|
12 (16.67)
|
9 (19.15)
|
0.454
|
0.32
|
Current smoker
|
13 (18.06)
|
8(17.02)
|
1.369
|
0.35
|
HbA1c (%)
|
5.88±0.40
|
6.04±0.76
|
-2.000
|
0.11
|
Uric Acid
|
304.23±47.30
|
325.44±50.68
|
1.267
|
0.27
|
Creatinine
|
67.35±12.69
|
59.39±10.96
|
2.598
|
0.22
|
Obesity
|
18 (25.00)
|
9 (19.15)
|
0.546
|
0.51
|
CAS: Carotid Artery Stenting; DSA: Digital Subtraction Angiography; HbA1c: glycosylated hemoglobin; Hypertension: systolic pressure≥140 mmHg and/ or diastolic pressure≥90 mmHg; Obesity: body mass index≥30 kg/m2.
Table 2 The hemodynamic data in the operation patients
TCD values
|
pre-operation
|
post-operation
|
30 days follow-up
|
MFV(cm/s)
|
47.65±17.24
|
62.37±18.25*
|
70.29±16.89*
|
CVR(cm/s)
|
23.39±10.21
|
27.47±12.13&
|
31.92±10.94*
|
PI
|
0.78±0.21
|
0.98±0.19*
|
1.02±0.20*
|
MFV: middle flow velocity; PI: pulsatility index; CVR: cerebral vascular reactivity; MCA: middle cerebral artery.
With the release of carotid artery stenosis and the reconstruction of cerebral blood flow after CAS, the MFV and PI increased significantly in the ipsilateral MCA,(*P<0.05); the CVR improved significantly at 30 days follow-up (*P<0.05); but the CVR had no statistical change at 24 hours after CAS (&P>0.05).
Table 3 The serum concentrations of GFAP and S100B in the operation patients
Group
|
GFAP(pg/ml)
|
S100B(ng/ml)
|
D1 (before DSA)
|
20.059±10.219
|
0.853±0.162
|
D2 (24h after DSA)
|
21.392±09.022
|
0.909±0.127
|
T1 (before CAS)
|
25.392±11.022
|
1.500±0.804
|
T2 (24h after CAS)
|
30.877±14.979
|
2.074±1.082
|
T3 (72h after CAS)
|
27.038±12.294
|
1.786±0.975
|
T4 (30d after CAS)
|
21.038±13.458
|
0.886±0.315
|