Cerebral collateral circulation is a network of blood vessels which stabilizes blood flow and maintains cerebral perfusion whenever the main arteries fail to provide an adequate blood supply, as happens in ischemic stroke. These arterial networks are able to divert blood flow to hypoperfused cerebral areas. The extent of the collateral circulation determines the volume of the salvageable tissue, the so-called “penumbra”. Clinically, this is associated with greater efficacy of reperfusion therapies (thrombolysis and thrombectomy) in terms of better short- and long-term functional outcomes, lower incidence of hemorrhagic transformation and of malignant oedema, and smaller cerebral infarctions. Recent advancements in brain imaging techniques (CT and MRI) allow us to study these anastomotic networks in detail and increase the likelihood of making effective therapeutic choices. In this narrative review we will investigate the pathophysiology, the clinical aspects, and the possible diagnostic and therapeutic role of collateral circulation in acute ischemic stroke.

BACKGROUND AND PURPOSE: The aspiration technique has gained a prominent role in mechanical thrombectomy. The thrombectomy goal is successful revascularization (modified TICI ≥ 2b) and first-pass effect. The purpose of this study was to evaluate the impact of the vessel-catheter ratio on the modified TICI ≥ 2b and first-pass effect. MATERIALS AND METHODS: This was a retrospective, single-center, cohort study. From January 2018 to April 2020, 111/206 (53.9%) were eligible after applying the exclusion criteria. Culprit vessel diameters were measured by 2 neuroradiologists, and the intraclass correlation coefficient was calculated. The receiver operating characteristic curve was used for assessing the vessel-catheter ratio cutoff for modified TICI ≥ 2b and the first-pass effect. Time to groin puncture and fibrinolysis were weighted using logistic regression. All possible intervals (interval size, 0.1; sliding interval, 0.01) of the vessel-catheter ratio were plotted, and the best and worst intervals were compared using the χ² test. RESULTS: Modified TICI ≥ 2b outcome was achieved in 75/111 (67.5%), and first-pass effect was achieved in 53/75 (70.6%). The MCA diameter was 2.1 mm with an intraclass correlation coefficient of 0.92. The optimal vessel-catheter ratio cutoffs for modified TICI ≥ 2b were ≤1.51 (accuracy = 0.67; 95% CI, 0.58–0.76; P = 0.001), and for first-pass effect, they were significant (≤1.33; P = .31). The modified TICI ≥ 2b odds ratio and relative risk were 9.2 (95% CI, 2.4–36.2; P = 0.002) and 3.2 (95% CI, 1.2–8.7; P = .024). The odds ratio remained significant after logistic regression (7.4; 95% CI, 1.7–32.5; P = .008). First-pass effect odds ratio and relative risk were not significant (2.1 and 1.5; P > .05, respectively). The modified TICI ≥ 2b best and worst vessel-catheter ratio intervals were not significantly different (55.6% versus 85.7%, P = .12). The first-pass effect best vessel-catheter ratio interval was significantly higher compared with the worst one (78.6% versus 40.0%, P = .03). CONCLUSIONS: The aspiration catheter should be selected according to culprit vessel diameter. The optimal vessel-catheter ratio cutoffs were ≤1.51 for modified TICI ≥ 2b with an odds ratio of 9.2 and a relative risk of 3.2.

Background: The major endovascular mechanic thrombectomy (MT) techniques are: Stent-Retriever (SR), aspiration first pass technique (ADAPT) and Solumbra (Aspiration + SR), which are interchangeable (defined as switching strategy (SS)). The purpose of this study is to report the added value of switching from ADAPT to Solumbra in unsuccessful revascularization stroke patients. Methods: This is a retrospective, single center, pragmatic, cohort study. From December 2017 to November 2019, 935 consecutive patients were admitted to the Stroke Unit and 176/935 (18.8%) were eligible for MT. In 135/176 (76.7%) patients, ADAPT was used as the first-line strategy. SS was defined as the difference between first technique adopted and the final technique. Revascularization was evaluated with modified Thrombolysis In Cerebral Infarction (TICI) with success defined as mTICI ≥ 2b. Procedural time (PT) and time to reperfusion (TTR) were recorded. Results: Stroke involved: Anterior circulation in 121/135 (89.6%) patients and posterior circulation in 14/135 (10.4%) patients. ADAPT was the most common first-line technique vs. both SR and Solumbra (135/176 (76.7%) vs. 10/176 (5.7%) vs. 31/176 (17.6%), respectively). In 28/135 (20.7%) patients, the mTICI was ≤ 2a requiring switch to Solumbra. The vessel’s diameter positively predicted SS result (odd ratio (OR) 1.12, confidence of interval (CI) 95% 1.03–1.22; p = 0.006). The mean number of passes before SS was 2.0 ± 1.2. ADAPT to Solumbra improved successful revascularization by 13.3% (107/135 (79.3%) vs. 125/135 (92.6%)). PT was superior for SS comparing with ADAPT (71.1 min (CI 95% 53.2–109.0) vs. 40.0 min (CI 95% 35.0–45.2); p = 0.0004), although, TTR was similar (324.1 min (CI 95% 311.4–387.0) vs. 311.4 min (CI 95% 285.5–338.7); p = 0.23). Conclusion: Successful revascularization was improved by 13.3% after switching form ADAPT to Solumbra (final mTICI ≥ 2b was 92.6%). Vessel’s diameter positively predicted recourse to SS.

Background and Aims: Stroke is the leading cause of seizures and epilepsy in adults; however, current guidelines lack robust recommendations for treating post-stroke seizures (PSSs) and epilepsy (PSE). This study aims to demonstrate the long-term safety and efficacy of lacosamide combined with non-vitamin K antagonist oral anticoagulants (NOACs) in patients with PSE and atrial fibrillation (AF). Methods: In this prospective longitudinal single-center study, 53 patients with concomitant PSE and AF, admitted between 2022 and 2023, received NOACs for AF management and lacosamide for seizure control. A control group of 53 patients with cardioembolic stroke, receiving NOACs (but without PSE), was matched by age, sex, and NIHSS scores to ensure comparability. Results: Over 24 months, 16 patients in the study group and 15 in the control group experienced new embolic events, with no significant difference between groups (p = 0.82). Seizure control improved significantly in the study group, with reduced frequency and severity. No severe adverse events from lacosamide were observed. Conclusions: The combination of NOACs and lacosamide is a safe and effective treatment for patients with AF and PSE and does not increase the risk of recurrent ischemic or hemorrhagic events. Further studies with larger sample sizes and longer follow-ups are needed to confirm these findings and optimize treatment protocols.

The association between atrial fibrillation (AF), acute coronary syndrome (ACS), and stroke is a complex scenario in which the assessment of both thrombotic and hemorrhagic risk is necessary for scheduling an individually tailored therapeutic plan. Recent clinical trials investigating new antithrombotic drugs and dual and triple pathways in high-risk cardiovascular patients have revealed a new therapeutic scenario. In this paper, we review the burden of ischemic stroke (IS) in patients post-myocardial infarction with and without atrial fibrillation and the possible therapeutic strategies from a stroke point of view.