In patients with severe middle cerebral artery (MCA), intracranial atherosclerotic disease (ICAD), the mechanism of stroke is multifactorial, but hemodynamic insufficiency plays a significant role. This finding is important in selecting a subgroup of patients who may benefit from revascularization 1).
Surgical treatment with ipsilateral decompressive hemicraniectomy (DHC) has been shown to dramatically improve survival rates. DHC currently lacks established inclusion criteria and additional research is needed to assess the impact of prognostic factors on functional outcome.
The mortality rate of patients with brain edema after malignant middle cerebral artery (MCA) infarction approaches 80 % without surgical intervention.
Alexander et al. searched MEDLINE, EMBASE and Cochrane library databases for randomised controlled trials (RCTs) enrolling patients suffering SO-MCAi comparing conservative management to DHC administered within 96 hours after stroke symptom onset. Outcomes were death and disability measured by the modified Rankin Scale (mRS). We used a random effects meta-analytical approach with subgroup analyses (time to treatment and age). We applied GRADE methods to rate quality/confidence/certainty of evidence.
7 RCTs were eligible (n=338 patients). We found DHC reduced death (69-30% in medical vs surgical groups, 39% fewer), and increased the number of patients with mRS of 2-3 (slight to moderate disability: 14-27%, increase of 13%), those with mRS 4 (severe disability: 10-32%, increase of 22%) and those with mRS 5 (very severe disability 7-11%: increase of 4%) (all differences p<0.0001). We judged quality/confidence/certainty of evidence high for death, low for functional outcome mRS 0-3, and moderate for mRS 0-4 (wide CIs and problems in concealment, blinding of outcome assessors and stopping early).
DHC in SO-MCAi results in large reductions in mortality. Most of those who would otherwise have died are left with severe or very severe disability: for example, inability to walk and a requirement for help with bodily needs, though uncertainty about the proportion with very severe, severe and moderate disability remains (low to moderate quality/confidence/certainty evidence) 2).
Li et al., searched English and Chinese databases for randomized controlled trials or observational studies published before August 2016. Outcomes included good functional outcome (GFO), mortality, and National Institutes of Health Stroke Scale and Barthel index scores.
This meta-analysis included 25 studies (1727 patients). There were statistically significant differences between decompressive hemicraniectomy (DHC) and conventional treatment (CT) groups in terms of GFO (P < 0.0001), mortality (P < 0.00001), and National Institutes of Health Stroke Scale and Barthel index scores (P < 0.0001) at different follow-up points. Significant differences were observed between the groups in survival with moderately severe disability (P < 0.00001); no differences were observed in survival with severe disability. In the subgroup analysis, in the DHC group, GFO was less in patients >60 years old (9.65%) versus ≤60 years old (38.94%); more patients >60 years old had moderately severe or severe disability (55.27%) compared with patients ≤60 years old (44.21%).
DHC could significantly improve GFO and reduces mortality of patients of all ages with malignant MCA infarction compared with CT, without increasing the number of patients surviving with severe disability. However, patients in the DHC group more frequently had moderately severe disability. Patients >60 years old with malignant MCA infarction had a higher risk of surviving with moderately severe or severe disability and less GFO 3).
A systematic search was conducted using MEDLINE, PubMed, EMBASE, Current Contents Connect, Cochrane library, Google Scholar, Science Direct and Web of Science. Original data was abstracted from each study and used to calculate a pooled odds ratio (OR) and 95% confidence interval (95% CI).
RESULTS: The overall OR for mRS 6 (death) at 6 months for decompressive surgery as compared with standard medical management revealed a statistically significant reduction with OR of 0.19 (95% CI: 0.10-0.37). The frequency of patients with mRS 2, 3 and 5 outcomes was higher in the decompressive surgery cohort; however, these outcomes did not reach statistical significance. On the other hand, the number of patients with a mRS score of 4 was significantly higher in the decompressive surgery cohort with an OR of 3.29 (95% CI: 1.76-6.13). The overall OR for mRS 6 (death) at 12 months for decompressive surgery as compared with standard medical management revealed a statistically significant reduction with OR of 0.17 (95% CI: 0.10-0.29). The frequency of patients with mRS 3 and 5 outcomes was higher in the decompressive surgery cohort; however, these outcomes did not reach statistical significance. On the other hand, the number of patients with a mRS score of 4 was significantly higher in the decompressive surgery cohort with an OR of 4.43 (95% CI: 2.27-8.66). In the long run it was also observed that the number of patients with a mRS score of 2 was significantly higher in the decompressive surgery cohort an OR of 4.51 (95% CI: 1.06-19.24).
CONCLUSIONS: Our results imply that surgical intervention decreased mortality of patients with fatal middle cerebral artery infarct at the expense of increasing the proportion suffering from substantial disability at the conclusion of follow up 4).