3.1 General characteristics
From January 2017 to December 2021, 665 consecutive patients were enrolled in the thrombectomy cohort. Among them, 562 (84.5%) were ischemic stroke in the anterior circulation. We enrolled 474 patients in the initial cohort according to the inclusion criteria. In total, 16 patients (3.4%) were excluded from the final analysis because of incomplete radiographic images (n=5) and lost to follow‐up (n=10). Consequently, 458 patients were analyzed (Figure 1).
The baseline characteristics of all participants according to MAP SD quartiles are shown in Table 1. The mean age of the participants was 71.7±10.7 years, and 56.8% were men. Among them, 74.2% had hypertension, 28.2% had diabetes mellitus, and 46.7% had atrial fibrillation[A1] . The mean baseline NIHSS score was 16.0±4.1, OTP time was 47.0 minutes (30.0–70.0), and onset-to-reperfusion time was 270.1±83.5 minutes.
Participants with higher BPV tended to be older, men, had lower ASPECT scores, higher baseline NIHSS scores, hypertension, and showed higher usage of continuous intravenous antihypertensive agents.
Table 1
Characteristics of the study population (n=458)
|
MAP SD, mmHg
|
|
|
ALL
n=458
|
Q1:2.8-7.1
n=115
|
Q2: 7.1-8.6
n=114
|
Q3: 8.6-10.5
n=114
|
Q4: 10.5-26.2
n=115
|
P Value
|
Demographic Characteristics
|
|
Age, year
|
71.7±10.7
|
69.1±10.9
|
70.6±11.0
|
72.6±9.9
|
74.3±10.4
|
0.001
|
Sex(male)
|
198 (43.2%)
|
40 (34.8%)
|
45 (39.5%)
|
53 (46.5%)
|
60 (52.2%)
|
0.041
|
Vascular risk factors
|
|
Hypertension
|
340 (74.2%)
|
77 (67.0%)
|
74 (64.9%)
|
94 (82.5%)
|
95 (82.6%)
|
<0.001
|
Diabetes mellitus
|
129 (28.2%)
|
24 (20.9%)
|
28 (24.6%)
|
39 (34.2%)
|
38 (33.0%)
|
0.067
|
Atrial fibrillation
|
214 (46.7%)
|
51 (44.3%)
|
57 (50.0%)
|
51 (44.7%)
|
55 (47.8%)
|
0.804
|
Admission variables
|
|
Level of occlusion on DSA imaging
|
|
|
|
|
|
0.739
|
ICA
|
185 (40.4%)
|
43 (37.4%)
|
43 (37.7%)
|
46 (40.4%)
|
53 (46.1%)
|
|
MCA 1
|
219 (47.8%)
|
57 (49.6%)
|
60 (52.6%)
|
54 (47.4%)
|
48 (41.7%)
|
|
MCA 2
|
54 (11.8%)
|
15 (13.0%)
|
11 (9.6%)
|
14 (12.3%)
|
14 (12.2%)
|
|
ASPECTS
|
|
|
|
|
|
0.024
|
6-8
|
261 (57.0%)
|
53 (46.1%)
|
63 (55.3%)
|
72 (63.2%)
|
73 (63.5%)
|
|
9-10
|
197 (43.0%)
|
62 (53.9%)
|
51 (44.7%)
|
42 (36.8%)
|
42 (36.5%)
|
|
Baseline NIHSS
|
16.0±4.1
|
15.9±4.0
|
15.0±3.9
|
15.5±3.7
|
17.6±4.4
|
<0.001
|
Procedural variables
|
|
Bridging treatment
|
197 (43.0%)
|
52 (45.2%)
|
47 (41.2%)
|
56 (49.1%)
|
42 (36.5%)
|
0.252
|
rescue treatment
|
75 (16.4%)
|
22 (19.1%)
|
19 (16.7%)
|
19 (16.7%)
|
15 (13.0%)
|
0.663
|
PTR time, minute
|
47.0 (30.0-70.0)
|
44.0 (28.0-69.0)
|
51.5 (33.2-71.5)
|
45.0 (31.0-65.0)
|
45.0 (27.0-70.5)
|
0.487
|
OTR time, minute
|
270.1±83.5
|
266.6±88.5
|
283.5±87.8
|
264.0±76.5
|
266.3±80.3
|
0.264
|
Continuous intravenous antihypertensive agents
|
353 (77.1%)
|
77 (67.0%)
|
81 (71.1%)
|
93 (81.6%)
|
102 (88.7%)
|
<0.001
|
Data reported as mean ± SD or median (IQR) for continuous variables or n (%) for categorical variables.
MAP, mean arterial pressure; SD, Standard Deviation; IQR, interquartile range; ASPECTS, Alberta Stroke Program Early CT Score; NIHSS, National Institutes of Health Stroke Scale; ICA, Internal carotid artery; MCA, middle cerebral artery; PTR, Puncture to recanalization; OTR, Onset to recanalization.
A total of 207 (45.2%) patients had unfavorable functional outcomes (mRS score 3–6) at 90 days; 61 (13.3%) patients died within 30 days, and 20 (4.4%) patients experienced sICH (Table 2). Patients with higher BPV tended to have a higher [A2] prevalence of futile recanalization, mortality, and sICH (Figure 2-4).
The results of the univariate analyses are summarized in Table S1. Univariate analyses revealed an increased incidence for each outcome in patients with higher BPV. No significant correlation was found between higher MAP means and each outcome.
According to the curve fitting results in Figure S1-3, we performed a multivariate logistic analysis to further explore MAP SD as a prognostic marker. In the multivariable analysis shown in Table 2, the MAP SD level was an independent risk factor for poor functional outcome at 90 days in Model I (OR adj=1.37, per 1-SD increase, 95% CI: 1.08–1.72, P = 0.009) and Model II (OR adj=1.31, per 1-SD increase, 95% CI: 1.01–1.68, P = 0.039). Multivariable logistic regression also revealed a significant association between MAP SD level and 30-day mortality and sICH.
Table 2
multivariable regression of MAP SD associated with clinical outcomes
Outcomes
|
Crude Model
|
Model I
|
Model II
|
|
OR(95% CI)
|
P Value
|
OR(95% CI)
|
P Value
|
OR(95% CI)
|
P Value
|
futile recanalization
|
|
|
|
|
|
|
MAP SD (mmHg)
|
1.17 (1.09, 1.26)
|
<0.001
|
1.11 (1.03, 1.21)
|
0.009
|
1.10 (1.00, 1.20)
|
0.039
|
MAP SD (per 1 SD)
|
1.59 (1.29, 1.95)
|
<0.001
|
1.37 (1.08, 1.73)
|
0.009
|
1.31 (1.01, 1.68)
|
0.039
|
30-day mortality
|
|
|
|
|
|
|
MAP SD (mmHg)
|
1.35 (1.22, 1.48)
|
<0.001
|
1.26 (1.13, 1.40)
|
<0.001
|
1.22 (1.09, 1.37)
|
0.001
|
MAP SD (per 1 SD)
|
2.36 (1.78, 3.14)
|
<0.001
|
1.95 (1.43, 2.65)
|
<0.001
|
1.80 (1.29, 2.50)
|
0.001
|
symptomatic intracerebral hemorrhage
|
|
|
|
|
|
|
MAP SD (mmHg)
|
1.23 (1.10, 1.37)
|
<0.001
|
1.20 (1.06, 1.36)
|
0.005
|
1.20 (1.05, 1.36)
|
0.007
|
MAP SD (per 1 SD)
|
1.81 (1.31, 2.52)
|
<0.001
|
1.70 (1.18, 2.45)
|
0.005
|
1.69 (1.15, 2.47)
|
0.007
|
Crude model adjust for: None.
Model I adjust for: Male, Age, Hypertension, Diabetes mellitus, Atrial fibrillation, Level of occlusion on DSA imaging, ASPECTS, Baseline NIHSS.
Model II adjust for: Male, Age, Hypertension, Diabetes mellitus, Atrial fibrillation, Level of occlusion on DSA imaging, ASPECTS, Baseline NIHSS, Puncture to recanalization, Onset to recanalization, rescue treatment, Continuous intravenous antihypertensive agents, Bridging treatment, MAP mean (Smooth only for 30-day mortality)
To evaluate other potentially influencing factors, we conducted a sub-analysis by stratifying patients according to age, sex, hypertension, diabetes mellitus, atrial fibrillation, and level of occlusion; ASPECT score, baseline NIHSS score, PTR time, OTR time, rescue treatment, continuous intravenous antihypertensive agents, bridging therapy, and mean MAP, as presented in Figure 5-6. The number of patients with sICH was low; therefore, subgroup analysis was not performed. Notably, all subgroups demonstrated a similar relationship [A1] between MAP SD level and post-operative futile recanalization and 30 day-mortality.
Figure 5 show the stratified analyses of futile recanalization between each subgroup. The interaction analysis revealed that rescue treatment played an interactive role in the association between BPV and futile recanalization (Figure 7). The patients who underwent rescue treatment had a higher odds ratio (OR) between BPV and futile recanalization (OR=1.97; 95% CI, 1.23–3.14; P =0.001) than those without rescue treatment (OR = 1.04; 95% CI, 0.95–1.14).
Figure 6 shows the stratified analyses of 30-day mortality between each subgroup. Logistic regression analysis did not demonstrate a significant relationship for 30 day-mortality between BPV and all subgroups (P > 0.05).
The above model adjusted for age groups, male, hypertension, diabetes mellitus, atrial fibrillation, level of occlusion; ASPECTS, Baseline NIHSS groups, PTR groups, OTR groups, rescue treatment, continuous intravenous antihypertensive agents, bridging treatment, and MAP mean groups. In each case, the model is not adjusted for the stratification variable
Figure 7 Smooth curve fitting of MAP SD and futile recanalization in rescue treatment subgroup
Adjustment variables: Male, Age, Hypertension, Diabetes mellitus, Atrial fibrillation, Level of occlusion on DSA imaging, ASPECTS, Baseline NIHSS, Puncture to recanalization, Onset to recanalization, rescue treatment, Continuous intravenous antihypertensive agents, Bridging treatment, MAP mean.
A brief sentence stating what relationship was demonstrated would enhance reader comprehension here.