Griessenaur, Christoph

Background: Patients with acute ischemic stroke secondary to distal and medium vessel occlusion (AIS-DMVO) and minor strokes present a challenge in determining the most appropriate emergent treatment. Factors leading to early neurological deterioration (END) in this patient population are understudied, but END is known to result in poor functional outcomes. Therefore, we aimed to investigate the factors contributing to END in minor AIS-DMVO cases. Methods: We included patients with AIS-DMVO and minor strokes from 37 sites across North America, Asia, and Europe. Minor stroke was defined as a baseline National Institutes of Health Stroke Scale (NIHSS) score of ⩽5. The primary outcome measure, END, was defined as a shift of ⩾4 points in the NIHSS score at day one after treatment compared to baseline. Univariable and multivariable logistic regression analyses were performed to identify factors associated with END. Results: Among 559 consecutive patients with DMVO and minor strokes, END was reported in 68 patients. In multivariable analysis, mechanical thrombectomy (MT) was independently associated with higher odds of END (adjusted odds ratio [aOR] 2.37, 95% CI 1.12–5.02, p = 0.02), while intravenous thrombolysis (IVT) was associated with lower odds of END (aOR 0.46, 95% CI 0.26–0.81, p = 0.008). However, the association between MT and END was no longer statistically significant in the IPTW-adjusted analysis (OR 1.65, 95% CI 0.69–3.98, p = 0.26). Hypertension and antiplatelet use at baseline were also independently associated with END. Among MT-treated patients, successful and excellent recanalization and first-pass effect were protective against END. Conclusion: MT was associated with END in patients with minor AIS-DMVO, although this association was not significant after IPTW adjustment. IVT was independently associated with reduced risk of END. These findings support careful patient selection and further study in randomized trials.

Background: Arteriovenous malformations (AVMs) are complex vascular anomalies with a high risk of hemorrhage and neurological deficits, especially when located in eloquent brain regions. The eloquence of an AVM location is a critical factor in the treatment planning, influencing both the risk of complications and long-term functional outcomes. This study aims to compare outcomes between eloquent and non-eloquent AVMs. Methods: This multicenter, retrospective study utilized data from the Multicenter International Study for Treatment of Brain AVMs (MISTA) consortium. Patients with eloquent and non-eloquent AVMs were compared on baseline characteristics, angiographic outcomes, and functional outcomes using the modified Rankin Scale (mRS). Propensity score weighting (IPTW) was applied to adjust for confounding variables. Results: The study included 1013 patients, with 498 (49.2%) AVMs located in eloquent regions and 515 (50.8%) in non-eloquent regions. In unadjusted analysis, eloquent AVMs had lower complete obliteration rates (67.6% vs 79.5%, OR: 0.53, 95% CI: 0.39–0.72, p < 0.001) and higher complication rates (24.5% vs 19.0%, OR: 1.38, 95% CI: 1.02–1.86, p = 0.03) compared to non-eloquent AVMs. After IPTW adjustment, eloquent AVMs continued to show significantly higher odds of overall complications (OR: 1.68, 95% CI: 1.12–2.52, p = 0.01) and symptomatic complications (OR: 1.77, 95% CI: 1.12–2.80, p = 0.01). Secondary analysis within the eloquent group indicated that embolization was linked to an elevated risk of complications. Surgery and radiosurgery showed comparable functional outcomes at last follow-up and complications rates with higher complete obliteration rates in surgery. Conclusion: AVMs in eloquent brain areas present higher risks of complications and lower obliteration rates, emphasizing the need for cautious, individualized treatment planning. Within the eloquent group, embolization increased the risk of complications, while surgery and radiosurgery showed comparable functional outcomes at last follow-up and complication rates with higher complete obliteration rates in surgery. These findings highlight the importance of location in AVM management and support further research focusing on comparing treatment strategies for AVMs in eloquent brain areas.

Background: Acute ischemic stroke (AIS) from distal medium vessel occlusion (DMVO) presents unique treatment challenges. Mechanical thrombectomy (MT) is emerging as a viable option for these patients, yet the role of pre-stroke aspirin treatment is unclear. This study evaluates the impact of pre-stroke low-dose aspirin on outcomes in DMVO patients undergoing MT. Methods: We conducted a multinational, multicenter, propensity score-weighted analysis within the Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy (MAD-MT) registry. Patients with AIS due to DMVO, treated with MT, were included. We compared outcomes between patients on pre-stroke low-dose aspirin (75–100 mg) and those not on antiplatelet therapy. The primary outcome was functional independence at 90 days (modified Rankin Scale (mRS), 0–2). Secondary outcomes included excellent functional outcome at 90 days (mRS, 0–1), mortality, and day 1 post-MT National Institutes of Health Stroke Scale (NIHSS) score. Safety outcomes focused on hemorrhagic complications, including symptomatic intracerebral hemorrhage (sICH). Results: Among 1354 patients, 150 were on pre-stroke low-dose aspirin. After applying inverse probability of treatment weighting (IPTW), aspirin use was associated with significantly better functional outcomes (mRS, 0–2: odds ratio (OR) = 1.89, 95% confidence interval (CI) = 1.14 to 3.12) and lower 90-day mortality (OR = 0.56, 95% CI = 0.32 to 1.00). The aspirin group had lower NIHSS scores on day 1 (β = −1.5, 95% CI = −2.8 to −0.27). The sICH rate was not significantly different between the groups (OR = 0.92, 95% CI = 0.60 to 1.43). Conclusions: Pre-stroke low-dose aspirin was associated with improved functional outcomes and reduced mortality in patients with DMVO undergoing MT, without a significant increase in sICH. These findings suggest that low-dose aspirin may be safe and associated with more frequent excellent outcomes for this patient population. Further prospective studies are needed to validate these results and assess long-term outcomes.