Between January 2021 and December 2022, a total of 621 individuals were subjected to MT for acute anterior circulation LVO across three general hospitals. After a meticulous screening process, 269 patients were ultimately included in the study. Notably, the following criteria led to the exclusion of certain individuals: 211 patients who did not undergo a head CT scan, 115 patients with occlusions in the internal carotid terminal or anterior cerebral artery that did not extend into the MCA segment, 9 patients without available follow-up CT/MRI images, and 17 patients who encountered unsuccessful MCA thrombectomy due to elongated carotid artery tortuosity. A visual representation of this selection process is provided in Figure 1.
HMCAS in patients with MCA occlusion
Out of the total sample of 269 patients, 85 (31.6%) displayed HMCAS on their initial NCCT scans(Fig 2). The mean age in the cohort was 65.44±13.01 years, with 186 (69.1%) being male. Among these patients, 95 (35.3%) exhibited HT, 255 (94.8%) achieved successful recanalization, and 138 (51.3%) experienced a favorable prognosis. Participants were stratified into two distinct groups: the HMCAS group and the Non-HMCAS group. In concordance with prior investigations [6, 10], the prevalence of hypertension and diabetes was higher in the Non-HMCAS group as compared to the HMCAS group (70.7% vs. 55.3%, p=0.014 for hypertension; 26.6% vs. 15.3%, p=0.04 for diabetes). Notably, there were no discernible differences between the two groups in terms of hyperlipidemia, previous stroke/transient ischemic attack (TIA), or smoking history. In the HMCAS group, a higher proportion of males and a greater incidence of atrial fibrillation were observed (78.8% vs. 64.7%, p=0.019 for males; 32.9% vs. 21.2%, p=0.038 for atrial fibrillation). Additionally, the HMCAS group exhibited a higher baseline NIHSS score and a lower ASPECTS (15 [11, 18] vs. 10.5 [6, 16], p < 0.001 for NIHSS; 9 [8, 10] vs. 9 [6, 10], p=0.005 for ASPECT). In terms of recanalization efficacy, the Non-HMCAS group demonstrated a higher rate of first-pass recanalization and a reduced number of procedural passes compared to the HMCAS group (38.0% vs. 22.4%, p=0.011 for first-pass recanalization; 2 [1, 3] vs. 2 [2, 4], p < 0.001 for the number of passes). Patients without HMCAS exhibited a significantly higher prevalence of favorable outcomes and a lower incidence of HT (50.6% vs. 28.3%, p < 0.001 for good outcomes; 41.2% vs. 56.0%, p=0.024 for HT) (Table 1).
HMCAS in patients with LAA
The included cases were categorized into two groups, LAA, and CE, based on the TOAST criteria. Among the individuals with LAA, 173 patients were further stratified based on the presence or absence of HMCAS into Non-HMCAS-LAA (n=130) and HMCAS-LAA (n=43) subgroups. Comparing these subgroups, it was evident that HMCAS-LAA patients exhibited a higher baseline NIHSS score (9.5 [4.75, 15] vs. 14 [10, 17], p=0.001). Furthermore, Non-HMCAS-LAA patients demonstrated a higher rate of first-pass recanalization and required fewer procedural passes than their HMCAS-LAA counterparts (33.8% vs. 16.3%, p=0.029 for first-pass recanalization; 2 [1, 2.5] vs. 3 [2, 4], p < 0.001 for the number of passes). However, there were no statistically significant differences in the rates of successful reperfusion and favorable 90-day outcomes between patients in the Non-HMCAS-LAA group and those in the HMCAS-LAA group (96.2% vs. 96.7%, p=0.637 for successful reperfusion; 57.7% vs. 58.2%, p=0.359 for good outcomes) (Table 2).
HMCAS in patients with CE
A total of 80 patients diagnosed with cardiac embolism were included in this study and categorized into two groups: the Non HMCAS-CE group (n=45) and the HMCAS-CE group (n=35). Notably, the HMCAS-CE group exhibited lower scores in terms of the ASPECTS and a reduced rate of first-pass recanalization (8 [6, 10] vs. 9 [8, 10], p=0.009 for ASPECT; 25.7% vs. 51.1%, p=0.021 for first-pass recanalization). Furthermore, patients in the HMCAS-CE group required more procedural passes (2 [1, 3] vs. 1 [1, 3], p=0.039). In contrast, the Non-HMCAS-CE group displayed a higher percentage of favorable outcomes and a lower incidence of HT (46.7% vs. 20.0%, p=0.013 for good outcomes; 33.3% vs. 65.7%, p=0.004 for HT) (Table 2).
The comparison of results between patients with a good prognosis (n=28) and those with a poor prognosis (n=52) in the CE subgroup is outlined in Table 3. In patients with CE, variables including intravenous thrombolysis, ASPECT, first-pass recanalization, the number of passes, HT, and the presence of HMCAS were all associated with the 90-day mRS. Multivariate logistic regression models were used for evaluating the association of HMCAS with the endpoints. These models were adjusted for age, gender, intravenous thrombolysis, baseline NIHSS, HCMAS, and OPT, and identified positive HMCAS as an independent risk factor for an unfavorable outcome (OR: 4.054, 95% CI: 1.161-14.159, p=0.028) (Table 4).