Marguerite Müller

Initial experience with a new distal intermediate and aspiration catheter in the treatment of acute ischemic stroke: clinical safety and efficacy

Purpose To describe our initial experience with the novel 5 F SOFIA (Soft Torqueable catheter Optimized For Intracranial Access) intermediate and aspiration catheter for endovascular treatment of patients with acute ischemic stroke. Methods A retrospective review was performed in three centers of prospectively collected data of all stroke patients who underwent endovascular therapy using the SOFIA catheter. Patients were enrolled between November 2013 and December 2014. The primary endpoint of the study was accessibility of the thrombus with the SOFIA catheter. As a secondary endpoint, the study assessed recanalization success (Thrombolysis In Cerebral Infarction (TICI) ≥2b). Clinical presentation on admission and discharge was also documented. In addition, catheter- and procedure-related complications (particularly thromboembolic complications) were recorded. Results The SOFIA catheter was used in 115 acute stroke procedures. In 110 cases (96%) the catheter could be advanced to the occlusion site. After mechanical thrombectomy, successful recanalization (TICI ≥2b) was documented in 86.9%. There were no complications related to positioning of the catheter. Distal thrombus migration into a new vascular territory occurred in three patients following thrombectomy with a stent retriever (2.6%). The mean NIH Stroke Scale (NIHSS) score on admission was 16.8±6 and at discharge the mean NIHSS score was 8.2±7.7. Sixteen patients died. Conclusions The SOFIA catheter is a safe and efficient catheter for endovascular stroke therapy.

Multicenter experience with the new SOFIA Plus catheter as a primary local aspiration catheter for acute stroke thrombectomy

Introduction The direct aspiration first pass technique (ADAPT) has been introduced as a rapid and safe endovascular treatment strategy in patients with ischemic stroke. Objective To determine the technical feasibility, safety, and functional outcome with ADAPT using the new large-bore 6F SOFIA Plus catheter. Methods A retrospective analysis of prospectively collected data from six university hospitals was performed. The following parameters of all acute stroke procedures (June 2015– January 2016) using the SOFIA Plus catheter were analyzed: accessibility of the thrombus with the catheter, recanalization success (Thrombolysis in Cerebral Infarction ≥2b), time to recanalization, procedure-related complications. Furthermore, National Institutes of Health Stroke Scale (NIHSS) scores at presentation and discharge and the modified Rankin scale (mRS) score at 90 days were recorded. Results 85 patients were treated using the SOFIA Plus catheter. The occlusion site was the anterior circulation in 94.1%. Median baseline NIHSS score was 18. In 64.7%, ADAPT alone was successful after a median procedure time of 21 min. With additional use of stent retrievers in the remaining cases, the recanalization rate was 96.5%. No catheter-related complications such as dissections were observed. Thrombus migration to a new vascular territory occurred in 4.7% and symptomatic hemorrhage in 4.7%. After 3 months, mRS 0–2 was achieved in 49.4%. Mortality rate was 20%. Conclusions In the majority of cases, thrombus aspiration using the SOFIA Plus catheter results in successful recanalization after a short procedure time. With additional use of stent retrievers, a high recanalization rate can be achieved (96.5%). The complication rate was in line with those of previous publications.

Active push deployment technique improves stent/vessel-wall interaction in endovascular treatment of acute stroke with stent retrievers.

Background The optimal interaction between stent struts and thrombus is crucial for successful revascularization in endovascular stroke therapy with stent retrievers. Deploying the stent retriever by actively pushing it into the thrombus increases the radial force with which the stent struts expand into the thrombus. Objective To examine the active push deployment (APD) technique in an in vitro model and present our clinical experience with this technique. Methods In an in vitro experiment we investigated the configuration of a Solitaire and a Trevo ProVue device (both 4×20 mm), depending on whether the devices were deployed using the APD technique or simple unsheathing. We retrospectively assessed the effectiveness and safety of this technique by analyzing 130 patients with large vessel occlusions (carotid T or M1 segment of the middle cerebral artery), who received endovascular treatment with a Trevo device (4×20 mm) that was deployed using the APD technique. Results In vitro experiment: the APD technique improved apposition of the devices to the vessel wall. There was widening of 30% (Trevo) and 19% (Solitaire) at the cost of a shortening of 5% and 4%, respectively, when the devices were deployed in a carotid T model. Clinical study: the revascularization rate (Thrombolysis in Cerebral Infarction ≥2b) with the Trevo device was 90%. There were no retriever-associated dissections or perforations in 278 retrieval maneuvers. Conclusions The APD technique improves apposition of the tested devices to the vessel wall. The widening effect comes at the cost of minimal shortening of the devices. Our clinical experience shows that using the APD technique to deploy the Trevo device is effective and safe.

Optimizing endovascular stroke treatment: removing the microcatheter before clot retrieval with stent-retrievers increases aspiration flow.

Background Flow control during endovascular stroke treatment with stent-retrievers is crucial for successful revascularization. The standard technique recommended by stent-retriever manufacturers implies obstruction of the respective access catheter by the microcatheter, through which the stent-retriever is delivered. This, in turn, results in reduced aspiration during thrombectomy. In order to maximize aspiration, we fully retract the microcatheter out of the access catheter before thrombectomy—an approach we term the ‘bare wire thrombectomy’ (BWT) technique. We verified the improved throughput with systematic in vitro studies and assessed the clinical effectiveness and safety of this method. Methods We compared aspiration flow of water through various access catheters (5–8 F) with a Rebar microcatheter (0.18 inch and 0.27 inch) and a Trevo stent-retriever using the standard technique and the BWT technique in vitro. We also retrospectively analyzed 302 retrieval maneuvers in 117 patients who received endovascular treatment with a stent-retriever between February 2010 and April 2015. Results In the in vitro experiment, removal of the microcatheter in all tested settings resulted in significantly increased aspiration flow through the access catheter (p<0.001). This effect was particularly pronounced in access catheters with a diameter of ≤7 F. In the clinical study, the revascularization rate (Thrombolysis In Cerebral Infarction ≥2b) was 91%. There were no complications associated with the BWT technique in 302 retrieval maneuvers. Conclusions The BWT technique results in improved aspiration flow rates compared with the standard deployment technique. Our clinical data show that the BWT technique is effective and safe.

Clinical Impact of Ventilation Duration in Patients with Stroke Undergoing Interventional Treatment under General Anesthesia: The Shorter the Better?

The authors investigated the impact of early extubation and ventilation duration in a cohort of 103 patients that underwent thrombectomy under general anesthesia. Prolonged ventilation was associated with pneumonia during hospitalization and unfavorable functional outcome (mRS greater than or equal to 3) and death at follow-up. According to ROC analysis, a cutoff after 24 hours predicted unfavorable functional outcome with a sensitivity and specificity of 60% and 78%, respectively. The authors conclude that short ventilation times are associated with a lower pneumonia rate and more favorable clinical outcome. BACKGROUND AND PURPOSE: Whether general anesthesia for neurothrombectomy in patients with ischemic stroke has a negative impact on clinical outcome is currently under discussion. We investigated the impact of early extubation and ventilation duration in a cohort that underwent thrombectomy under general anesthesia. MATERIALS AND METHODS: We analyzed 103 consecutive patients from a prospective stroke registry. They met the following criteria: CTA-proved large-vessel occlusion in the anterior circulation, ASPECTS above 6 on presenting cranial CT, revascularization by thrombectomy with the patient under general anesthesia within 6 hours after onset of symptoms, and available functional outcome (mRS) 90 days after onset. RESULTS: The mean ventilation time was 128.07 ± 265.51 hours (median, 18.5 hours; range, 1–1244.7 hours). Prolonged ventilation was associated with pneumonia during hospitalization and unfavorable functional outcome (mRS ≥3) and death at follow-up (Mann-Whitney U test; P ≤ .001). According to receiver operating characteristic analysis, a cutoff after 24 hours predicted unfavorable functional outcome with a sensitivity and specificity of 60% and 78%, respectively. Our results imply that delayed extubation was not associated with a less favorable clinical outcome compared with immediate extubation after the procedure. CONCLUSIONS: Short ventilation times are associated with a lower pneumonia rate and more favorable clinical outcome. Cautious interpretation of our data implies that whether patients are extubated immediately after the procedure is irrelevant for clinical outcome as long as ventilation does not exceed 24 hours.

Endovascular Rescue Therapies for Refractory Vasospasm After Subarachnoid Hemorrhage: A Prospective Evaluation Study Using Multimodal, Continuous Event Neuromonitoring

BACKGROUND Critical hypoperfusion and metabolic derangement are frequently encountered with refractory vasospasm. Endovascular rescue therapies (ERT) have proven beneficial in selected cases. However, angioplasty (AP) and intraarterial lysis (IAL) are measures of last resort and prospective, quantitative results regarding the efficacy (cerebral oxygenation, metabolism) are largely lacking. OBJECTIVE To evaluate the efficacy of ERTs for medically refractory vasospasm using multimodal, continuous event neuromonitoring. METHODS To detect cerebral compromise in a timely fashion, sedated patients with aneurysmal subarachnoid hemorrhage received continuous neuromonitoring (p ti O 2 measurement, intraparenchymal microdialysis). ERT (AP and/or IAL) was considered in cases of clinically relevant vasospasm refractory to conservative treatment measures. Oxygen saturation and cerebral and systemic metabolism before and after events of ERT was recorded. RESULTS We prospectively included 13 consecutive patients and recorded a total of 25 ERT events: AP (n = 10), IAL (n = 11), or both (AP + IAL, n = 4). Average cerebral p ti O 2 was 10 ± 11 torr before and 49 ± 22 torr after ERT ( P < .001), with a lactate-pyruvate ratio decreasing from 146.6 ± 119.0 to 27.9 ± 10.7 after ERT ( P < .001). Comparable improvement was observed for each type of intervention (AP, IAL, or both). No significant alterations in systemic metabolism could be detected after ERT. CONCLUSION Multimodal event neuromonitoring is able to quantify treatment efficacy in subarachnoid hemorrhage-related vasospasm. In our small cohort of highly selected cases, ERT was associated with improvement in cerebral oxygenation and metabolism with reasonable outcome. Event neuromonitoring may facilitate individual and timely optimization of treatment modality according to the individual clinical course.

Weekend effect in endovascular stroke treatment: do treatment decisions, procedural times, and outcome depend on time of admission?

Background Epidemiologic studies identified a ‘weekend effect’ or ‘out-of-hours effect’, which implies that procedural and clinical outcomes of patients with stroke, who are admitted out-of-hours, are less favorable than for patients admitted during working-hours. Objective To determine (1) whether our procedural times and clinical outcome were affected by an out-of-hours effect and (2) whether the decision in favor of, or against, endovascular stroke treatment (EST) depends on the time of admission. Methods Between February 2010 and January 2015, 6412 consecutive patients presenting with symptoms of acute ischemic stroke were evaluated for EST eligibility according to established local protocols and generally accepted consensus criteria, and dichotomized into working-hours and out-of-hours cohorts according to admission times. Within both groups, patients given EST were identified and the rate of treatment decision, procedural times, and clinical outcome were compared and analyzed. Results Clinical and radiological features of patients admitted in working-hours and out-of-hours did not differ significantly. Procedural times and clinical outcome were not affected by an out-of-hours effect (p≥0.054). 221/240 (92.1%) out-of-hours patients and 154/166 (92.8%) working-hours patients who were eligible for EST were transferred to the angiography suite for EST (p=0.798). The rationale not to treat patients who were eligible for EST did not differ between working-hours and out-of-hours admission (p=0.756). Conclusions It is possible to produce competitive procedural times regardless of the time of admission and to prevent a treatment decision bias when standard operating procedures are applied consistently.

Temporary Stent-Assisted Coil Embolization as a Treatment Option for Wide-Neck Aneurysms

The authors intended to treat 33 aneurysms between January 2010 and December 2015 with temporary stent-assisted coiling, which formed the series for this study. Incidental and acutely ruptured aneurysms were included. Sufficient occlusion was achieved in 97.1% of the cases. In 94%, the stent could be fully recovered. Complications occurred in 5 patients (14.7%). They conclude that temporary stent-assisted coiling is an effective technique for the treatment of wide-neck aneurysms. Safety is comparable with that of stent-assisted coiling and coiling with balloon remodeling. BACKGROUND AND PURPOSE: Simple coil embolization is often not a feasible treatment option in wide-neck aneurysms. Stent-assisted coil embolization helps stabilize the coils within the aneurysm. Permanent placement of a stent in an intracranial vessel, however, requires long-term platelet inhibition. Temporary stent-assisted coiling is an alternative technique for the treatment of wide-neck aneurysms. To date, only case reports and small case series have been published. Our purpose was to retrospectively analyze the effectiveness and safety of temporary stent-assisted coiling in a larger cohort. MATERIALS AND METHODS: Research was performed for all patients who had undergone endovascular aneurysm treatment in our institution (University Hospital Aachen) between January 2010 and December 2015. During this period, 355 consecutive patients had undergone endovascular aneurysm treatment. We intended to treat 33 (9.2%) of them with temporary stent-assisted coiling, and they were included in this study. Incidental and acutely ruptured aneurysms were included. RESULTS: Sufficient occlusion was achieved in 97.1% of the cases. In 94%, the stent could be fully recovered. Complications occurred in 5 patients (14.7%), whereas in only 1 case was the complication seen as specific to stent-assisted coiling. CONCLUSIONS: Temporary stent-assisted coiling is an effective technique for the treatment of wide-neck aneurysms. Safety is comparable with that of stent-assisted coiling and coiling with balloon remodeling.

Diagnostic performance of different perfusion algorithms for the detection of angiographical spasm

PURPOSE To assess the diagnostic utility of different perfusion algorithms for the detection of angiographical terial spasm. METHOD During a 2-year period, 45 datasets from 29 patients (54.2±10,75y, 20F) with suspected cerebral vasospasm after aneurysmal subarachnoid hemorrhage were included. Volume Perfusion CT (VPCT), Non-enhanced CT (NCT) and angiography were performed within 6hours post-ictus. Perfusion maps were generated using a maximum slope (MS) and a deconvolution-based approach (DC). Two blinded neuroradiologists independently evaluated MS and DC maps regarding vasospasm-related perfusion impairment on a 3-point Likert-scale (0=no impairment, 1=impairment affecting <50%, 2=impairment affecting >50% of vascular territory). A third independent neuroradiologist assessed angiography for presence and severity of arterial narrowing on a 3-point Likert scale (0=no narrowing, 1=narrowing affecting <50%, 2=narrowing affecting>50% of artery diameter). MS and DC perfusion maps were evaluated regarding diagnostic accuracy for angiographical arterial spasm with angiography as reference standard. Correlation analysis of angiography findings with both MS and DC perfusion maps was additionally performed. Furthermor, the agreement between MS and DC and inter-reader agreement was assessed. RESULTS DC maps yielded significantly higher diagnostic accuracy than MS perfusion maps (DC:AUC=.870; MS:AUC=.805; P=0.007) with higher sensitivity for DC compared to MS (DC:sensitivity=.758; MS:sensitivity=.625). DC maps revealed stronger correlation with angiography than MS (DC: R=.788; MS: R=694;=<0.001). MS and DC showed substantial agreement (Kappa=.626). Regarding inter-reader analysis, (almost) perfect inter-reader agreement was observed for both MS and DC maps (Kappa≥981). CONCLUSION DC yields significantly higher diagnostic accuracy for the detection of angiographic arterial spasm and higher correlation with angiographic findings compared to MS.

Endovascular stentectomy using the snare over stent-retriever (SOS) technique: An experimental feasibility study

Feasibility of endovascular stentectomy using a snare over stent-retriever (SOS) technique was evaluated in a silicon flow model and an in vivo swine model. In vitro, stentectomy of different intracranial stents using the SOS technique was feasible in 22 out of 24 (92%) retrieval maneuvers. In vivo, stentectomy was successful in 10 out of 10 procedures (100%). In one case self-limiting vasospasm was observed angiographically as a technique related complication in the animal model. Endovascular stentectomy using the SOS technique is feasible in an experimental setting and may be transferred to a clinical scenario.