WSO - January 2024 - 46

46
International Journal of Stroke 19(1)
Table 3. Results of sensitivity analysis of risk factors.
Risk factors
Age ⩾ 65 years
Hypertension
Stenosis site (bulb)
Severe stenosis
Severe contralateral carotid stenosis
The stenosis proximity (⩽10 mm) to bifurcation
Symptomatic stenosis
Ulcerated plaque
Calcified plaques
Stent type
Bilateral carotid stenting
Post-balloon dilation
Intravenous fluid intake/mL in the first 24 h after surgery
Sex (male)
CI: confidence interval; OR: odds ratio; MD: mean difference.
test (t = 1.35, P = 0.1962) further confirmed the funnel plot
results, which may be related to the disparity in sample
sizes among the included studies (Figure 5).
Discussion
High incidence of hypotension after CAS
The results of this study demonstrated a 28.6% (95% CI
(0.225, 0.347)) incidence of hypotension after carotid stenting,
which is similar to the results of previous studies.
Previous studies have suggested that the incidence of hypotension
after carotid stenting was approximately 23.1%-
31.2% according to different criteria.3-5 Among the 17
included studies, 14 studies defined hypotension as a systolic
blood pressure <90 mmHg in patients despite adequate
treatment after CAS. However, 1 Korean study and 1
Japanese study defined it as a systolic blood pressure
<80 mmHg,7,10 and 1 Japanese study defined it as a
systolic blood pressure <100 mmHg,17 which may be
because there are no uniform criteria for the diagnosis of
hypotension.13 The occurrence of postoperative hypotension
in CAS patients is the result of the synergistic effect of
multiple factors. The carotid sinus is located at the beginning
of the internal carotid artery or at the bifurcation of the
carotid artery. When implementing CAS, carotid sinus
pressure receptors are stimulated, and the development of
International Journal of Stroke, 19(1)
hypotension may occur. The carotid artery is an important
and vital blood vessel for the blood supply to the brain, and
transient or persistent hypotension can affect cerebral perfusion
and body circulation.27 Previous studies have confirmed
that persistent hypotension can cause cerebral
hypoperfusion, aggravate existing cerebral ischemic symptoms,
increase hospitalization times, and even increase the
risks of cerebrovascular disease.22,27 In addition, patients
with postoperative hypotension in CAS are more prone to
perioperative transient ischemic attack, stroke, and infarction
complications than other patients.28 Therefore, it is crucial
to identify the risk factors for postoperative hypotension
in CAS patients for its prevention.
Preoperative factors
The results of this meta-analysis showed that age ⩾65 years,
bulb stenosis, severe stenosis, stenosis proximity (⩽10 mm)
to bifurcation, and calcified plaques were risk factors for
the occurrence of hypotension in patients after CAS. The
incidence of postoperative hypotension after CAS was
4.55-times higher in those individuals aged ⩾65 years than
in those individuals aged <65 years. This result is consistent
with the study of Lamanna et al.29 This effect may be
due to the replacement of pacemaker cells in the sinus node
by fibrous connective tissue in elderly patients, thus resulting
in a slower heart rate. However, some researchers23,25,30
Random-effects model
OR/MD (95% CI)
4.55 (2.50, 8.29)
1.59 (0.58, 4.36)
3.91 (2.18, 6.98)
3.56 (1.62, 7.85)
2.69 (0.76, 9.48)
2.61 (1.68, 4.05)
1.66 (0.66, 4.22)
2.00 (0.53, 7.55)
4.64 (1.93, 11.14)
2.76 (1.00, 7.62)
30.51 (2.33, 399.89)
6.30 (2.23, 17.79)
444.99 (141.40, 748.59)
1.07 (0.87, 1.31)
Fixed-effects model
OR/MD (95% CI)
4.55 (2.50, 8.29)
1.34 (1.03, 1.74)
4.41 (2.50, 7.79)
2.50 (1.81, 3.45)
1.81 (1.22, 2.86)
2.69 (1.74, 4.15)
1.33 (0.94, 1.90)
1.97 (1.12, 3.47)
2.67 (2.09, 3.42)
1.85 (1.36, 2.51)
19.10 (5.98, 60.97)
5.95 (2.31, 15.31)
444.99 (141.40, 748.59)
1.09 (0.89, 1.33)
WSO - January 2024

Table of Contents for the Digital Edition of WSO - January 2024
