Propensity Matched Comparison of Periprocedural Ischemic Brain Lesions on Postprocedural
MR in Open vs. Endovascular Carotid Artery Reconstruction
Zsuzsanna Mihaly, Samuel Booth, Dat Nguyen, Milan Vecsey-Nagy, Zsófia Czinege, Edit Dosa,
Peter Sotonyi, Andrea Varga
Heart and Vascular Center, Semmelweis University
Aim:
The purpose of this study was to eliminate the patient and plaque characteristics related
differences with propensity matched design and determine the risk of the procedure related
new ischemic brain lesions in patients who underwent CAS and CEA.
Methods:
Retrospective single center matched case control study enrolled patient between 1st January
2019 and 11th January 2021. CAS was performed with embolic protection device and local
anesthesia; CEA was performed in general anesthesia with NIRS neuromonitoring and selective
shunting.
Propensity score-based matching was performed in a 1:1 ratio to compare outcomes in patients
treated with CEA and CAS (matching factors: age, gender, hypertension, diabetes mellitus,
smoking, dyslipidemia, and plaque location as well as quantitative plaque parameters: total
calcified plaque volume, the volume of intraplaque hemorrhage, lipid-rich necrotic core and
matrix, the length of the lesion, the remodeling ratio, and the degree of area stenosis). Preprocedural computed tomography angiography (CTA) was acquired, and quantitative plaque
characteristics were determined using VascuCAP (Elucid Bioimaging) carotid plaque image
analysis software. Post-procedural MRI was performed 12 to 48 hours after procedure and
evaluated by a neuroradiologist for the presence of new DWI and chronic ischemic brain lesion
volume and number.
Results:
A total of 111 patients (78 CEAs and 33 CAS), who underwent carotid interventions, were
enrolled. Significant differences were detected between the groups in both baseline patient
(hypertension p=0.0005, diabetes p=0.0001) and plaque characteristics (calcium volume
p=0.0056 and plaque lengths p=0.0444). Propensity score matching resulted in 21 appropriate
pairs of patients underwent CEA and CAS interventions. There was no perioperative
neurological event in any of the groups. In the CAS group, 10 patients had new ischemic lesions
and 3 patients with new lesions in CEA group (p=0.02) and DWI lesion volume was significantly
higher in the CAS group (p=0.04). There was no significant difference in chronic lesion volume in
the two groups.
Conclusions:
Patients who underwent CAS and CEA differed in both cardiovascular risk factors and plaque
features, however, propensity matching was able to alleviate the differences between the
groups. The absolute number of patients with new and chronic DWI lesions was higher in the
group that received CAS with preliminary statistical analysis revealing no significant differences.
The procedure related new ischemic lesions are significantly higher in the CAS group as well.
Table 1: Baseline patient and plaque characteristics before and after propensity matching
Before Propensity Matching
N=111
CAS
N=33
CEA
N=78
Hypertensio
n
29
(88%)
Diabetes
7(21%)
42
(54%)
56
(72%)
CALCVol
(mm3)
Plaque
Length
(mm)
Media
n (Q1
- Q3)
Media
n (Q1 Q3)
34.4
(19.6 90.30)
24.7
(18.9 –
32.8)
86.1
(42.8 –
160.1)
28.8
(22.6 –
37.8)
21 Propensity Matched Pairs
p
(Fisher‘s
Exact
test)
N=42
CAS
N=21
CEA
N=21
p
(Fisher’s
Exact
test)
0.0005
Hypertensio
n
17
(81%)
19
(90%)
0.6628
0.0001
Diabetes
7 (33%)
6 (29%)
1.0000
Median
(Q1 –
Q3)
Median
(Q1 –
Q3)
p
(Mann
Whitney
U test)
40.9
(27.4 –
91.1)
26.4
(20.8 –
32.9)
52.2
(25.2 –
188.4)
27.5
(19.8 –
36.4)
p
(Mann
Whitney
U test)
0.0056
CALCVol
(mm3)
0.04444
Plaque
Length
(mm)
0.5961
0.93624
Table 2
Comparison of new and chronic cerebral lesions between the groups
CAS
CEA
p
New DWI lesion appeared (yes/no)
N=21
N=21
10 (47.6%)
3 (14.3%)
DWI lesion localization
0.02
0.08
None
11 (52.4%)
18 (85.7%)
Ipsilateral
6 (28.6%)
3 (14.3%)
Contralateral
3 (14.3%)
0
Bilateral
1 (4.7%)
0
Total
0.0 (0.0-45.3)
0.0 (0.0-0.0)
0.04
Ipsilateral
0.0 (0.0-31.6)
0.0 (0.0-0.0)
0.14
Contralateral
0.0 (0.0-0.0)
0.0 (0.0-0.0)
0.07
Total
2.0 (0.5-4.0)
2.0 (0.0-3.5)
0.39
Ipsilateral
1.0 (0.0-2.0)
1.0 (0.0-2.0)
0.35
Contralateral
1.0 (0.5-1.5)
1.0 (0.0-2.0)
0.34
0.0 (0.0-1379.3)
0.0 (0.0-10.4)
0.18
Ipsilateral
0.0 (0.0-26.0)
0.0 (0.0)
0.44
Contralateral
0.0 (0.0-0.0)
0.0 (0.0-0.0)
0.12
DWI lesion volume
Fazekas scale
Chronic lesion volume
Total
Continuous data are presented as median and interquartile ranges, while categorical variables are
shown as numbers and percentages.