Wiebke Kurre

Risk Assessment of Symptomatic Intracerebral Hemorrhage After Thrombolysis Using DWI-ASPECTS

Background and Purpose— Pretreatment lesion size on diffusion-weighted imaging (DWI) is a risk factor for symptomatic intracerebral hemorrhage (sICH) associated with thrombolytic treatment. Here, we investigated whether the Alberta Stroke Programme Early CT Score (ASPECTS) applied to DWI images (DWI-ASPECTS) predicts sICH risk accurately. Methods— In this retrospective multicenter study, prospectively collected data of 217 patients with anterior circulation stroke treated with intravenous or intraarterial thrombolysis within 6 hours after symptom onset were analyzed. Pretreatment DWI-ASPECTS scores were assessed by 2 independent investigators. For bleeding risk analysis, DWI-ASPECTS scores were either categorized into 0 to 7 (n=105) or 8 to 10 (n=112) or in 3 groups of similar sample size (DWI-ASPECTS 0 to 5 [n=69], 6 to 7 [n=70], and 8 to 10 [n=78]). Results— DWI-ASPECTS scores correlated well with the DWI lesion volume (r=0.77, P<0.001, Spearman Rank test). Interobserver reliability for the assessment of DWI-ASPECTS was moderate (weighted kappa 0.441 [95% CI 0.373 to 0.509]). Twenty-three (10.6%) patients developed sICH. The sICH rate was significantly higher in patients with DWI-ASPECTS scores 0 to 7 (n=21, 15.1%) as compared to patients with DWI-ASPECTS scores 8 to 10 (n=2, 2.6%, P=0.004). sICH risk was 20.3%, 10%, and 2.6% in the 0 to 5, 6 to 7, and 8 to 10 DWI-ASPECTS groups, respectively. DWI-ASPECTS remained an independent prognostic factor for sICH after adjustment for clinical baseline variables (age, NIHSS, time to thrombolysis). Conclusions— DWI-ASPECTS predicts sICH risk after thrombolysis and may be helpful to contributing to quick sICH risk assessment before thrombolytic therapy.

In-Hospital Complication Rates After Stent Treatment of 388 Symptomatic Intracranial Stenoses Results From the INTRASTENT Multicentric Registry

Background and Purpose— Stenting is increasingly used as an adjunct to medical therapy in symptomatic intracranial stenoses. High periprocedural adverse event rates are one of the limitations of endovascular treatment. Data from the INTRASTENT multicentric registry should demonstrate in-hospital complications at the current stage of clinical development of the stent procedure. Methods— Participating centers entered the records of all their consecutive intracranial stent procedures into the database. To determine the clinical outcome in the acute phase, we distinguished transient ischemic attack/nondisabling stroke (modified Rankin Scale <2), disabling stroke, death, and intracranial hemorrhage as clinical complications and analyzed whether they were associated with patient- or stenosis-related risk factors. Results— Data from 372 patients with 388 stenoses proved 4.8% disabling strokes and 2.2% deaths. Transient or minor events were detected in 5.4% of the cases. Hemorrhagic events (3.5%) occurred more frequently after treatment of middle cerebral artery stenoses (P=0.004) and were associated with significantly higher morbidity and mortality rates. Ischemic strokes by compromise of perforating branches were detected mainly in the posterior circulation. However, the overall rate of severe adverse events was not dependent from location, degree, and morphology of the stenosis or from patients age, gender, vascular risk factors, or type of qualifying event. Conclusion— The complication rates within the registry are within the limits of previously published data. Severe adverse events were equally distributed between potential risk groups with similar rates but different types of main complications in the anterior and posterior circulation.

Materials and techniques for coiling of cerebral aneurysms: how much scientific evidence do we have?

IntroductionSince coils were approved for aneurysm treatment, materials and techniques developed rapidly. It still remains an open question whether one material or method is superior. This article reviews the literature on various coil types and treatment approaches assessing the scientific evidence of its use.Materials and methodsStudies on aneurysm treatment with Guglielmi detachable platinum coils, bioactive coils, hydrogel coated coils, and complex designs as well as balloon- and stent-assisted techniques were retrieved by a PubMed database search from 1990 until May 2008. Data were analyzed in terms of aneurysm occlusion, permanent morbidity and mortality, recanalization, and retreatment. We also assessed the level of evidence of the published studies.ResultsOnly the International Subarachnoid Aneurysm Trial provides level I evidence proving the superiority of endovascular over surgical therapy in ruptured aneurysms. Randomized trials comparing bioactive or hydrogel coated devices with bare coils are ongoing. Other studies were based on registries or case series mainly conducted without control groups. Morbidity, mortality, and initial occlusion rates appear similar for all devices. No clear evidence exists for the superiority of bioactive- or hydrocoils regarding long-term stability. It remains ambiguous whether morbidity and mortality rises with the use of balloons and stents. There is no evidence that routine use of balloons improves treatment durability. Mid-term results of stent-assisted coiling of complex aneurysms appear favorable.ConclusionThere is a lack of studies with a high level of evidence comparing different coiling materials and techniques. Case series and registries were not able to prove the superiority of any device or method.

Pipeline embolization device for the treatment of intra- and extracranial fusiform and dissecting aneurysms: initial experience and long-term follow-up.

BACKGROUND Flow-diverting stents offer a promising treatment option for complex aneurysms. OBJECTIVE To evaluate the safety and efficacy of the Pipeline embolization device (PED) in the treatment of fusiform and dissecting aneurysms. METHODS Sixty-five consecutive patients with 69 fusiform and dissecting aneurysms underwent endovascular treatment with the use of the PED. Target vessels included the internal carotid artery (n = 28), middle cerebral artery (n = 2), anterior cerebral artery (n = 1), vertebral artery (n = 20), basilar artery (n = 17), and posterior cerebral artery (n = 1). An average of 3.0 PEDs per target vessel were deployed. RESULTS Exclusion of the aneurysm(s) immediately after PED deployment was not observed. Angiographic follow-up examinations were performed in 63/65 patients (67/69 lesions). They showed complete cure of the target lesion in the first follow-up angiography (3.4 months mean interval) in 24 (36%) cases, partial elimination in 30 (45%), and no improvement in 13 (19%). After the latest follow-up (>1 digital subtraction angiography, n = 49, 27.4 months mean interval) complete cure of the target lesion was observed in 33 (67%), partial elimination in 14 (29%), and no change in 2 (4%). Taking all follow-up examinations together, 39/67 (58%) aneurysms were cured. The morbidity and mortality in the entire series were 5% and 8%, respectively. CONCLUSION Flow diverters offer a promising treatment option in fusiform and dissecting aneurysms. The introduction of flow diverters with different densities might help to identify the optimal amount of coverage needed given different anatomic presentations of fusiform and dissecting aneurysms.

Predictors of Outcome after Mechanical Thrombectomy for Anterior Circulation Large Vessel Occlusion in Patients Aged ≥ 80 Years

Background: There is uncertainty about the role of endovascular recanalization procedures for the treatment of acute ischemic stroke in patients aged ≥80 years. Therefore, careful patient selection is mandatory. Our aim was to find valid predictors of clinical outcome after mechanical thrombectomy (mTE) based on the sparse information available in the emergency setting. Methods: We included consecutive patients aged ≥80 years treated by mTE for anterior circulation thromboembolic vessel occlusion in our department between January 2008 and January 2013. Successful recanalization was defined as a thrombolysis in cerebral infarction (TICI) score of 2b or 3. The rates of parenchymal hemorrhage types I (PHI) and II (PHII) according to the ECASS definition and the rate of focal and diffuse subarachnoid hemorrhage (SAH) were reported. A modified Ranking scale (mRS) score of 0-2 at 90 days was defined as a favorable outcome. We evaluated the influence of gender, smoking habits, atrial fibrillation, diabetes, hypertension, hyperlipidemia, coronary artery and peripheral artery disease, National Institutes of Health Stroke Scale (NIHSS) score, Totaled Health Risks in Vascular Events (THRIVE) score, Alberta Stroke Program Early CT Score (ASPECTS), and duration of symptoms on favorable outcome. Significant predictors were then included in a stepwise logistic regression analysis. Odds ratios (OR), 95% confidence intervals (CI), and receiver operating characteristics (ROC) curves were calculated. p < 0.05 was considered statistically significant. Results: In the defined period, we treated 109 patients aged ≥80 years with 116 occluded anterior circulation target vessels. Successful recanalization was achieved in 87.9% of the targets. The rates of PHI, PHII, and focal and diffuse SAH were 6.4, 5.5, 12.8, and 7.3%, with an overlap between PH and SAH. The combined rate of PHII and/or diffuse SAH was 9.2%. Despite good recanalization rates and reasonable rates of hemorrhage, only 19 patients (17.4%) were functionally independent at 90 days. An additional 12 patients (11.0%) suffered from moderate disability (mRS score 3), 26 (23.9%) were severely disabled (mRS score 4-5) and 52 (47.7%) were deceased. NIHSS, ASPECTS, and THRIVE scores significantly predicted a favorable outcome. Stepwise logistic regression identified NIHSS (OR 0.89; 95% CI 0.82-0.96; p = 0.009) and ASPECTS (OR 2.27; 95% CI 1.28-4.02; p = 0.005) as independent predictors. The ROC area was 0.81. Conclusion: ASPECTS and NIHSS were independent predictors of a favorable outcome in patients aged ≥80 years after mTE for anterior circulation large vessel occlusion and may support decision making with regard to the treatment modality. Since the chances of gaining functional independence are limited, careful consideration of each individual case is mandatory. Further studies comparing endovascular and standard treatment in octogenarians are warranted.

Complication rates using balloon-expandable and self-expanding stents for the treatment of intracranial atherosclerotic stenoses : analysis of the INTRASTENT multicentric registry.

IntroductionUsing balloon-expandable stents (BES) for treatment of intracranial stenoses, high inflation pressures and rigidity of the device are regarded as major drawbacks limiting feasibility and safety of the procedure. Self-expanding stents (SES) were developed to facilitate lesion access and to allow for less aggressive dilatation. We analyzed data of the INTRASTENT multicentric registry to assess whether self-expanding stents significantly reduced peri-interventional complication rates.MethodsRecords of intracranial stent procedures were entered consecutively into the registry. Datasets were divided into two groups according to the type of stent used. For outcome measurement, we chose three categories: TIA/minor stroke [modified Rankin score (mRS) <2], disabling stroke, and patient death. Clinical outcome was compared between BES and SES. We analyzed types of adverse events occurring in each group in addition.ResultsOf 409 atherosclerotic lesions, 254 were treated with BES and 155 with SES. Technical success rates were 97.6% and 98.7%, respectively. Adverse event rates were 4.9%, 3.7%, and 0.8% for TIA/nondisabling stroke, disabling stroke, and death in the BES group compared with 5.3%, 6.0%, and 4.0% in the SES group. The differences were not statistically significant. We observed more perforator strokes after use of BES, but thromboembolic events occurred more often in the SES treatment group.ConclusionData of the INTRASTENT registry do not support the hypothesis that introduction of SES lowered the overall complication rate of intracranial stent procedures. There might be an advantage using self-expanding stents in vessel segments with important perforating arteries.

Intracranial stenting in atherosclerotic disease—recent results and challenges to face

Intracranial stenting is increasingly used as an add-on to medical therapy despite the fact that the overall clinical benefit remains a matter of debate, since we lack results of randomized trials. Decision making on interventional treatment is made on the grounds of the anticipated risk of stroke with antiplatelet medication on one hand and on the experience with stent treatment based on data from case series and registries on the other hand. This review will summarize the current knowledge on both topics serving as the fundament of patient selection for intracranial stenting. A second objective is to highlight some specific problems that are encountered when treating patients interventionally. Procedure-related complication rates and rates of in stent stenoses are still too high to be confident that endovascular treatment is superior to medical therapy of symptomatic stenoses. Optimization of patient selection criteria, stent technology, and periprocedural management are necessary to become undoubtedly competitive with antiplatelet therapy. With the current stage of development, interventional treatment of intracranial stenoses should be confined to specialized centers with a high expertise in neurovascular procedures.

Recanalization Results After Intracranial Stenting of Atherosclerotic Stenoses

The purpose of this investigation was to provide a detailed description of the angiographic results after stenting of high-grade intracranial stenosis using balloon-expandable stents. Forty consecutive patients with symptomatic atherosclerotic intracranial stenosis >50% received endovascular treatment by placement of balloon-expandable stents using the concept of slight underdilation and strict avoidance of overdilation. Intra-arterial digital subtraction angiography images before and after stenting in the same projection were reviewed for pre- and post-therapeutic measurement of the degree of stenosis and evaluation of morphologic criteria like plaque coverage, stent apposition, patency of side branches, and signs of dissection or vasospasm. Stenting decreased the mean percentage stenosis from 76.2 (WASID criteria) to 20.8%. Residual stenosis ranged from 0 to 55% with residual stenosis >50% in two of 40 cases. Technical success rate was 95%. There were no major vessel complications, but minor abnormalities like incomplete stent apposition (8/40) or plaque coverage (7/40), incomplete filling of side branches (13/40), and minor dissections after stenting (2/40) were seen. One case with incomplete stent apposition and two cases with side branch compromise were associated with clinical symptoms. In conclusion, intracranial stenting with slight underdilation avoided major vessel complication and created reliable luminal gain. Suboptimal recanalization results were frequently detected and may be the source of neurological complications in individual cases.

Treatment of Intracranial Atherosclerotic Stenoses

Intracranial atherosclerosis is the most important cause of stroke worldwide. A thorough knowledge of this disease is necessary to establish the best treatment strategy for each individual patient.

IQWiG Arbeitspapier GA15-02: „Stents zur Behandlung intrakranieller Stenosen: VISSIT Studie und Akutbehandlung in Deutschland“

ZusammenfassungGegenwärtig wird die Streichung der Stentbehandlung intrakranieller Stenosen aus dem Leistungskatalog der Gesetzlichen Krankenversicherungen (GKV) im Gemeinsamen Bundesausschuss (GBA) diskutiert. Ausgelöst wurde das Verfahren auf Antrag der GKV nach Veröffentlichung der SAMMPRIS1 Studie, die einen Vorteil für die konservative Behandlung im Vergleich zur Stentangioplastie mit dem Wingspan®-Stent zeigte. Diskussionsgrundlage ist ein seitens des Instituts für Qualität und Wirtschaftlichkeit (IQWiG) verfasstes Gutachten (Rapid Report N14-01), das im Wesentlichen auf den SAMMPRIS Ergebnissen fusst. Dieses Gutachten wurde von den involvierten Fachgesellschaften bereits kommentiert. Sowohl die Limitationen der SAMMPRIS Studie als auch Indikationen für die intrakranielle Stentangioplastie, die aus medizinischer Sicht unberührt bleiben müssen, wurden benannt (akute Gefäßverschlüsse, hämodynamisch relevante Stenosen, Stenosen mit rezidivierenden Symptomen unter konservativer Behandlung).Aktuell steht auch die Vergütung der Stentbehandlung in Notfallsituationen zur Disposition. In diesem Zusammenhang wurde ein neues IQWiG Gutachten in Auftrag gegeben (GA 15-02), das neben der Bewertung der kürzlich publizierten VISSIT Studie auch eine Überprüfung der Übertragbarkeit der Ergebnisse des überwiegend auf der SAMMPRIS Studie beruhenden Erstgutachtens auf „Akutbehandlungen“ und eine Analyse von „Akutbehandlungen“ in Deutschland zum Inhalt hat. Gemäß diesem Gutachten gäbe es keine Anhaltspunkte, dass die Studien, die der generellen Bewertung zugrunde liegen (überwiegend SAMMPRIS), nicht auch auf die Akutbehandlungen übertragen werden könnten. Aus medizinischer und wissenschaftlicher Sicht ist eine solche Übertragung von Studienergebnissen zur Sekundärprophylaxe auf die Notfallkonstellation nicht möglich. Die Analyse der Akutbehandlungen in Deutschland beruht auf retrospektiven Fallserien mit kumulativ 31 Patienten. Da die meisten der Notfallbehandlungen im klinischen Kontext stattfinden und nicht zwingend Gegenstand einer wissenschaftlichen Auswertung sind, wird hierdurch die medizinische Realität nicht abgebildet.Im ersten Abschnitt der Stellungnahme wird in komprimierter Form auf die Konzeption der SAMMPRIS und VISSIT Studie und die Interpretation der Studienergebnisse aus neuromedizinisch-fachlicher Perspektive eingegangen. Der bisherige Diskussionsstand im GBA wird zusammengefasst. Im zweiten Teil wird das aktuelle IQWiG Arbeitspapier GA15-02 „Stents zur Behandlung intrakranieller Stenosen: VISSIT Studie und Akutbehandlung in Deutschland“ detailliert kommentiert.AbstractThere is an ongoing discussion about reimbursement of stent-angioplasty for the treatment of intracranial stenoses in Germany. The discussion was initiated by the statutory health insurance companies after publication of the SAMMPRIS study results, which were in favor for medical management compared to stent-angioplasty with the Wingspan® stent system. A report (Rapid report N14-01) mainly based on SAMMPRIS was written by the German Institute for Quality and Efficiency in Health Care (IQWiG) and serves as a basis for the decision-making process. This report was previously commented by the medical societies involved. Limitations of the SAMMPRIS trial and vital indications for intracranial stenting were outlined in this comment (acute vessel occlusion, hemodynamic impairment, recurrent symptoms under medical treatment).Currently also emergency stent procedures are a matter of debate. In this context a second IQWiG report was commissioned (GA 15 − 02) addressing the results of the VISSIT trial, the transferability of the results of the first report to emergency treatments and the practice of emergency intracranial stent treatment in Germany6. Regarding transferability of results the main conclusion was that there was no evidence that the results of the studies analyzed for the first report (mainly SAMMPRIS) could not be transferred to emergency treatments. From a medical professional and scientific standpoint it is inacceptable to compare outcomes of a secondary prophylactic treatment with emergency procedures. The analysis of emergency treatments in Germany based on retrospective case series with a cumulative number of 31 patients. Since most emergency procedures are performed in a clinical context and are not necessarily subject to scientific evaluation, this does not reflect current practice in Germany.The first part of this statement briefly outlines the design of SAMMPRIS and VISSIT and the interpretation of the trial results from a professional perspective. The current state of discussion regarding reimbursement of intracranial stenting is summarized. The second section contains a detailed comment on the current IQWiG report GA15-02 “Stents for the treatment of intracranial artery stenosis: VISSIT study and acute treatment in Germany”.