Distance to thrombus, ischemic lesion volume and clinical outcome after thrombectomy for M1 middle cerebral artery occlusion.

BACKGROUND: Stroke resulting from occlusion of the middle cerebral artery (MCA) can have devastating consequences, potentially leading to a loss of independence. This study aimed to investigate the relationship between the distance to the thrombus (DT) and both ischemic lesion volume (ILV) and clinical outcomes. METHODS: We retrospectively evaluated patients with thromboembolic MCA M1 segment occlusion who underwent neurovascular imaging followed by endovascular thrombectomy (EVT) at two comprehensive stroke centers over a 3-year period (2018-2020). Preinterventional computed tomography (CT) or magnetic resonance (MR) angiography was used to measure DT, defined as the distance from the carotid­T bifurcation to the proximal surface of the M1 occlusion. Postinterventional CT or MR imaging was employed to determine the ILV and clinical outcomes were assessed using the modified Rankin scale (mRS) at 3 months. RESULTS: There were 346 patients evaluated. The median DT was 9.4 mm (interquartile range, IQR 6.0-13.7 mm) and the median ILV was 13.9 ml (IQR 2.2-53.1 ml). After adjustment, an increase in DT was associated with a decrease in odds for a larger ILV (odds ratio, OR 0.96, 95% confidence interval, CI 0.92-0.99, p = 0.041). Through this association, more distal thrombi were associated with good clinical outcome (mRS 0-2; clinical outcome available in 282 patients, p = 0.018). The ILV was inversely associated with better clinical outcome OR 0.52 (95% CI 0.40-0.67). CONCLUSION: Based on the findings, DT was identified as an independent albeit weak predictor for ILV and clinical outcomes in patients with MCA M1 occlusion who underwent EVT.

Follow-up after carotid stenting with the CASPER stent system: A duplex ultrasound evaluation.

OBJECTIVE: To report results of duplex ultrasound evaluation of consecutive patients after carotid stenting with the double layer Carotid Artery Stent designed to Prevent Embolic Release (CASPER) stent system. METHODS: Between January 2014 and June 2017, a single-center, retrospective study of 101 consecutive patients (21.8% female; median age, 72.1 years) was performed. Patients with internal carotid artery stenosis treated with the CASPER stent were included. Eligibility criteria for stenting included stenosis of ≥70% of the vessel diameter (or ≥50% diameter with ulceration) in symptomatic carotid artery stenosis or ≥80% stenosis in asymptomatic patients at the carotid artery bifurcation or the proximal cervical internal carotid artery. Duplex ultrasound examination was performed before and within 24 hours of implantation as well as at 14 days, and 3, 6, and 12 months. RESULTS: At the 12-month follow-up visit, moderate in-stent restenosis (ISR) (≥50% and <70%) was detected in three stents (2.8%) and severe (≥70%) ISR in two (1.9%; including one case of stent occlusion). All but the two latter patients remained asymptomatic during the follow-up period. One patient required retreatment for ISR after a minor stroke and another patient with stent occlusion also re-presented with a minor stroke. Multivariable logistic regression was unable to detect any significant factors associated with ISR. CONCLUSIONS: Duplex ultrasound examination after carotid stenting is a useful tool for patient follow-up and determination of ISR. We found a low incidence of ISR assessed by duplex ultrasound examination at 12 months after CASPER stenting, but further studies are warranted.

Blood pressure characteristics in patients with acute basilar artery occlusion undergoing endovascular thrombectomy.

Acute basilar artery occlusion (BAO) is a rare but potentially life-threatening neurological condition. While endovascular therapy (EVT) has been shown to improve outcome, there is limited knowledge about prognostic factors beyond early recanalization. We studied whether blood pressure (BP) exceeds or falls below suggested thresholds during intervention and whether these changes are associated with complications and outcome. BP measurements mostly with one-minute intervals were available in 39 patients. An individual systolic blood pressure (SBP) reference value was defined as the median of the first five intra-procedural measurements. Half of the patients (51.3%) received drugs for BP augmentation and two a BP lowering drug (5.1%). Thrombolysis in cerebral infarction grade 2b and 3 (TICI) was achieved in 29 (74.4%) and 23 patients (58.9%) had good outcome at three months. We observed a continuous intra-procedural increase of median SBP (+11%) and mean arterial pressure (MAP, +10%, both p < 0.001), and a unique temporal pattern of intermittent peaks and troughs. Successful recanalization was more common in patients whose intra-procedural duration with SBP under 140 mmHg was shorter (p = 0.009). Patients with isolated tip of basilar artery (TBA) occlusion had significantly more BP excursion of 20% below the reference SBP and required more frequent use of sympathomimetic drugs compared to vertebrobasilar occlusion (p = 0.008 and p = 0.041, respectively). Brain hemorrhage was more prevalent in patients who experienced SBP excursions at least 20% above the individual reference value (p = 0.038) and a longer duration of time spent with SBP above 180 mmHg (p = 0.029). Patients with higher pre-procedural mean SBP had a greater chance of a good outcome (p = 0.03). This study using high resolution BP monitoring suggests a relationship between intra-procedural BP characteristics and recanalization, hemorrhagic complications and outcome in patients receiving EVT for acute posterior circulation cerebrovascular syndromes. Differences with regard to BP regulation during recanalization therapy for vertebrobasilar and TBA occlusion deserves further attention.

Influence of the circle of Willis on leptomeningeal collateral flow in anterior circulation occlusive stroke: Friend or foe?

BACKGROUND: Clinical outcome after large vessel occlusion (LVO) stroke depends on collateral integrity. We aimed to evaluate whether the completeness of the circle of Willis (CoW) and anterior temporal artery (ATA) determines the status of leptomeningeal collaterals (LC) in patients with acute LVO (internal carotid artery (ICA) and middle cerebral artery M1 (MCA) occlusion) treated with endovascular thrombectomy. PATIENTS AND METHODS: LC, cross-flow through the anterior communicating artery (ACoA), presence of the ipsilateral posterior communicating artery (IpsiPCoA) and presence of the ATA were evaluated using CT angiography. LC was graded as good when ≥50% collateral filling was noted compared to the unaffected hemisphere. RESULTS: We included 159 patients with a median age of 75 years (IQR 63-82), MCA M1 occlusion in 96 (60%) and good outcome in 68 (45.6%). The LC were good in 129 (81.1%) patients. Complete IpsiPCoA and incomplete ACoA status was inversely associated with good LC in LVO (OR 0.51 (95% CI 0.02-0.07)). A complete CoW was associated with good LC in ICA occlusions, OR 8.4 (p = .025). Good outcome (modified Rankin scale 0-2 at 3 months) was associated with good LC (OR 5.63 (95% CI 1.11-28.4)), small ischemic lesion volume (OR 0.94 (95% CI 0.97-0.98)) and absence of the ACoA and IpsiPCoA (OR 4.47 (95% CI 1.09-18.3)). CONCLUSIONS: ATA presence was associated with good leptomeningeal collaterals in LVO (OR 8.13 (95% CI 1.69-39.0)) and in MCA M1 patients (OR 7.9 (95% CI 1.7-36.4)). The effect of ATA was most pronounced in MCA M1 occlusions, and that of ACoA was most pronounced in ICA occlusions.

The Casper Stent System for carotid artery stenosis.

PURPOSE: To report the results of a retrospective analysis of prospectively collected data evaluating the safety and efficacy of a double layer stent engineered for carotid artery occlusive disease. METHODS: Between January 2014 and February 2017, 138 patients (25.4% women; median age 71 years) underwent Casper stent implantation for carotid artery stenosis. Eligibility criteria included stenosis >70% of vessel diameter (or >50% diameter with ulceration) in symptomatic patients or asymptomatic patients with >80% stenosis at the carotid bifurcation or in the proximal internal carotid artery. For all procedures, a distal embolic protection device was used. The primary endpoint was the rate of 90 day major adverse neurological events, defined as minor stroke, major stroke, or death by independent neurological assessment. RESULTS: Stent deployment was completed successfully in all cases without documented technical failure. There were no adverse neurological events or mortalities within 90 days. One thromboembolic occlusion of a small distal branch of the anterior cerebral artery occurred during the procedure and resolved with systemic recombinant tissue plasminogen activator administration. New ischemic lesions, all clinically silent, were seen in 6.5% of patients on post-procedure cerebral MRI. CONCLUSION: The Casper carotid stent demonstrated safety and efficacy in the treatment of carotid stenosis, with no technical failures and no adverse neurological events seen throughout the 90 day follow-up period. Its double layer structure seems to combine adequate plaque scaffolding with high vessel adaptability.