First-Pass Effect in Basilar Artery Occlusions: Insights From the Endovascular Treatment of Ischemic Stroke Registry.

BACKGROUND AND PURPOSE: In the settings of thrombectomy, the first-pass effect (FPE), defined by a complete recanalization after one pass with no rescue therapy, has been shown to be associated with an improved outcome. As this phenomenon has been predominantly described in anterior circulation strokes, we aimed to study the prevalence, outcomes, and predictors of FPE in patients with a basilar artery occlusion. METHODS: From a prospective multicentric registry, we collected the data of all consecutive basilar artery occlusion patients who underwent thrombectomy and compared the outcomes of patients who achieved FPE and those who did not. We also compared FPE patients with those who achieved a complete recanalization with >1 pass. Finally, a multivariate analysis was performed to determine the predictors of FPE. RESULTS: Data from 280 patients were analyzed in our study, including 84 of 280 patients (30%) with an atheromatous etiology. An FPE was achieved in 93 patients (33.2%), with a significantly higher proportion of good outcomes (modified Rankin Scale score 0-2 at 3 months) and lower mortality than non-FPE patients. An FPE was also associated with improved outcomes compared with patients who went on to have full recanalization with >1 pass. Contact aspiration as first-line strategy was a strong predictor of FPE, whereas baseline antiplatelets and atheromatous etiology were negative predictors. CONCLUSIONS: In our study, an FPE was achieved in approximately one-third of patients with a basilar artery occlusion and was associated with improved outcomes. More research is needed to improve devices and techniques to increase the incidence of FPE. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03776877.

Angiographic Evolution of Brain Arteriovenous Malformation Angioarchitecture After Partial Endovascular Treatment.

BACKGROUND AND OBJECTIVES: Endovascular embolization of brain arteriovenous malformations (AVMs) is sometimes intentionally partial, in the case of staged treatment for instance. Residual AVMs may be prone to angioarchitectural modification during follow-up. The objective of this work is to evaluate the nature and extent of these modifications. METHODS: We performed a retrospective monocentric study on a cohort of adult patients treated by incomplete endovascular embolization for ruptured and unruptured AVMs with an available angiographic follow-up, without any intervening confounding event between the 2 angiographic examinations. AVM angioarchitectural modifications (arterial, nidal, and venous) were analyzed. Clinical and radiological data were tested in univariate analyses for association with the occurrence of AVM regression or progression. RESULTS: Eighty-two partial embolization sessions in 57 patients were included in the study. A 40% (33/82) rate of modification was found on follow-up, with 23/82 (28%) controls showing at least one angioarchitectural regression feature and 15/82 (18.3%) showing at least one angioarchitectural progression item. Nidal growth was the most frequent modification occurring after 12/82 (14.6%) embolizations. The only factor associated with nidal volume growth was a longer time interval between embolization and follow-up (median [IQR]: 190 [250] days vs 89.5[133] days in the subgroup without nidal growth; P = .02). Specific modifications of arterial supply, nidal anatomy, and venous drainage were identified and documented. CONCLUSION: Angioarchitectural modifications (both progression and regression) of brain AVMs are frequent findings after partial embolization. Nidal volume growth is associated with longer time intervals between embolization and follow-up.

Results of watchful waiting of unruptured intracranial aneurysms in a Western patient population: a single-center cohort.

BACKGROUND: The natural history of unruptured intracranial aneurysms (UIAs) in Western populations is still debated, especially for those <7 mm. Reporting data of a large single-center cohort managed with watchful waiting is therefore interesting. METHODS: From January 2011 to June 2019, 662 UIAs were followed up by yearly MR angiography. Morphologically stable UIAs were managed conservatively while unstable UIAs were offered treatment. The patients' clinical and radiological data were analyzed retrospectively. RESULTS: UIAs were ≤4 mm in 60%, 4.1-7.0 mm in 33%, and >7 mm in 7%. They were located on the anterior circulation in 90% of cases. The mean follow-up duration was 51.32 months for a total of 2831 aneurysm-years. During follow-up, 37 UIAs (5.5%) were treated because of an increase in size, and 8 UIAs were treated because of patient decision. Three aneurysms ruptured during follow-up for an annual risk of rupture of 0.1% (95% CI 0% to 0.24%). No risk factors for rupture were identified. The three ruptured cases made an excellent recovery. During follow-up, annual mortality from unrelated causes was 0.8% (95% CI 0.51% to 1.18%). CONCLUSIONS: This single-center cohort evaluated our watchful waiting policy applied in two-thirds of all incidental UIAs. Morphological change of UIAs during follow-up led to treatment in 5.5% of cases. With such a management paradigm, we found a low rupture rate in these selected UIAs and the mortality was unrelated to aneurysms.

Strategies for embolization of direct arteriovenous shunts in brain arteriovenous malformations.

Intranidal direct arteriovenous (AV) shunts are rarely observed in brain arteriovenous malformations (bAVMs).1 The endovascular treatment of such direct AV shunts may be challenging. Indeed, there is a significant risk of venous migration of the embolic agent used to occlude the AV shunt, leading to a subsequent risk of nidus bleeding due to impairment (slowdown or even occlusion) of the bAVM's venous drainage.2 Various endovascular techniques have been developed to avoid the risk of such inopportune impairment of the venous drainage during attempts to occlude a direct intranidal AV shunt.3-5 We present in this Technical Video (video 1) different endovascular strategies to occlude such direct AV shunts using dual-lumen balloons with various liquid embolic agents, or using occlusion plugs. neurintsurg;13/11/1064/V1F1V1Video 1.

Thrombectomy for Basilar Artery Occlusion with Mild Symptoms.

BACKGROUND AND OBJECTIVE: To evaluate outcomes of thrombectomy in patients with a basilar artery occlusion (BAO) and mild symptoms, defined by an initial National Institutes of Health Stroke Scale (NIHSS) score ≤6. METHODS: We performed a retrospective analysis of a multicenter prospective cohort of consecutive patients with acute ischemic stroke with BAO who underwent thrombectomy. We compared baseline and procedural characteristics, as well as outcomes between patients with BAO with an NIHSS score ≤6 and >6. Multivariate analyses were performed to determine baseline and procedural predictors of good outcome (modified Rankin Scale score 0-2) among patients with an NIHSS score ≤6. RESULTS: A total of 269 patients were included: 50 (19%) had an initial NIHSS score ≤6 and 219 (81%) had an NIHSS score >6. Patients with mild strokes (NIHSS score ≤6) had better outcomes (68% of modified Rankin Scale score 0-2 vs. 27% for NIHSS score >6; P < 0.0001), lower mortality (14% vs. 48; P < 0.0001) and fewer parenchymal hematomas at day 1 (0% vs. 10%; P = 0.016). A multivariate analysis identified the following predictors for good outcome among patients with BAO with an NIHSS score ≤6: younger age, fewer passes, a cardioembolic cause, and the absence of need for angioplasty/stenting. CONCLUSIONS: Thrombectomy seems to be safer and more effective for mild BAO strokes with NIHSS score ≤6 than for more severe patients. Even although thrombectomy showed high rates of recanalization, a substantial proportion (32%) nevertheless had a poor long-term clinical outcome. The number of passes, patient's age, and stroke cause seem to be predictors of clinical outcome.

Thrombectomy for Comatose Patients with Basilar Artery Occlusion : A Multicenter Study.

PURPOSE: Acute ischemic stroke (AIS) secondary to a basilar artery occlusion (BAO) carries a poor prognosis, especially in cases of severe symptoms, such as coma at presentation. Despite a lack of evidence, mechanical thrombectomy (MT) is often performed as the procedural risks are felt to be minimal compared to the natural history. We sought to evaluate MT efficacy and safety in comatose BAO patients. METHODS: We performed a retrospective analysis of a multicenter prospective cohort of consecutive AIS patients with BAO who underwent MT. We compared baseline characteristics between comatose and noncomatose BAO patients, as well as clinical outcomes (modified Rankin scale, mRS 0-3 at 3 months). Using a multivariate logistic regression, we examined the population of comatose patients for baseline predictive factors of mortality. RESULTS: We included 269 patients, 72 (27%) comatose and 197 (73%) non-comatose. Despite similar recanalization rates between comatose and non-comatose patients (83% vs. 90% p = 0.221), comatose patient long-term outcomes were dramatically worse (11% mRS 0-3 vs. 54%, p < 0.0001) and mortality was higher (64% vs. 34%, p < 0.0001). Baseline predictors of mortality at 3 months among comatose BAO patients after multivariate analysis were the following: male sex (odds ratio, OR 31.20, 2.57-378.52, p = 0.007), older age (OR 1.13, 1.04-1.24, p = 0.007) and higher serum glucose levels (OR 1.54, 1.07-2.21, p = 0.019). CONCLUSION: Thrombectomy is technically effective for BAO patients presenting with coma; however, the long-term favorable outcome remains poor. Male sex, old age and hyperglycemia were predictors of mortality in these patients.