Past, present, and future of endovascular stroke therapies

Endovascular therapy in the acute management of ischemic stroke has become more common with technologic advances, such as easier navigation into the intracranial circulation and improved treatment efficacy with the advent of revascularization devices. This select review outlines milestones in the application of endovascular therapy in acute ischemic stroke (AIS) and offers some insight into important factors influencing the future directions of endovascular AIS treatment. In particular, we discuss the evolution of endovascular devices for AIS and how ingenuity continues to offer novel treatments. With these advances, the future of endovascular AIS treatment is promising.

Abstract 3471: Emergent Carotid Artery Stenting: Outcomes on a National Level

Background: Emergent carotid artery stenting (CAS) is sometimes performed in the setting of acute cerebral ischemia. In this study, we assess outcomes associated with CAS when performed emergently.

Methods: A cohort of patients with CAS was identified from the National Inpatient Sample database using the procedure codes (00.63) for the years 2004 through 2007. The type of admission (elective or emergent) for each patient was clarified in the database. Patients with missing admission type were eliminated. We further ascertained the emergent hospitalization by including only patients who were admitted through the Emergency Department. Primary outcomes include stroke (ischemic or hemorrhagic), myocardial infarction or death occurring during the same hospitalization. Multivariate logistic regression analyses were used to assess covariates associated with the primary outcome and hospital mortality.

Results: In this analysis, 9001 patients were admitted and treated with CAS; 822 patients (9.13%) had the procedure performed emergently and the rest had elective CAS. The mean age (69.0 ± 13.2 vs. 70.6 ± 10.2) and gender (females 40.4% vs. 39.8%) were similar in both groups. Risk factors included higher rates of congestive failure and chronic lung disease in the emergent group. In addition, emergent CAS had more severe Charlson comorbidity index (4.0% vs. 1.76%; p < 0.0001). Unadjusted analysis showed higher rate of any stroke, myocardial infarction or death in the emergent group (12.3% vs. 3.37%; OR 4.0; 95% CI 3.15, 5.10). Adjusted analysis for the basic demographic, risk factors and the comorbidity index revealed a higher risk of any stroke, myocardial infarction and death when CAS performed emergently (OR 3.27; (95% CI, 2.54, 4.21). Secondary outcomes of hospital mortality (5.11% vs. 0.67%), myocardial infarction (5.47% vs. 1.11%) and intracerebral hemorrhage (2.07% vs. 0.35%) were higher in the emergent CAS group (P < 0.0001). Post-operative stroke rates were similar (1.92% vs. 1.82%; P= 0.85). Intracerebral hemorrhage was the strongest predictor of mortality (OR 64.0; 95% CI 32.1, 127.7). Other predictors of mortality include congestive heart failure, myocardial infarction and the use of thrombolytic.

Conclusion: CAS is associated with higher risk of stroke, myocardial infarction and death when performed emergently. Despite the low rate of intracerebral hemorrhage when CAS performed emergently, intracerebral hemorrhage remains the strongest predictor of mortality.

Acutely ruptured intracranial saccular aneurysms treated with stent assisted coiling: complications and outcomes in 42 consecutive patients

BACKGROUND

Antiplatelet agents are required to prevent thromboembolic complications from recently deployed intracranial stents, yet they carry a risk of bleeding complications that may be serious in patients with recent subarachnoid hemorrhage.

METHOD

Consecutive patients at a single institution who had ruptured intracranial saccular aneurysms treated with stent assisted coiling were retrospectively reviewed. Our primary outcomes were ischemic stroke related to the stent and bleeding complications possibly related to antithrombotic therapy. Secondary outcomes included 3 month follow-up National Institute of Health Stroke Scale (NIHSS) scores and modified Rankin Scale (mRS) scores.

RESULTS

44 aneurysms in 42 patients were treated. Seven patients experienced ischemic strokes during their hospitalization. Five ischemic strokes were secondary to vasospasm; one was definitely related to thrombus formation within the stent and one was possibly related to the stent. Two patients had asymptomatic intracranial hemorrhages and one patient had a symptomatic intracranial hemorrhage. Patients with Hunt and Hess grades I-II (n=25) experienced no stent associated ischemic strokes or symptomatic intracranial hemorrhages. The two stent associated ischemic strokes and one symptomatic intracranial hemorrhage occurred in patients with Hunt and Hess grades III-V (n=17) and patients with external ventricular drains (EVDs) (n=17). Only one patient had disability at the 3 month follow-up that was possibly related to the stent (mRS score of 3 and NIHSS score of 2).

CONCLUSION

These data suggest that higher grade hemorrhage patients, especially those with EVDs, are at greater risk for ischemic stroke and/or bleeding complications than lower grade patients. However, the complications had a small impact on mid-term disability outcomes in this cohort.

Education Research: The challenge of incorporating formal research methodology training in a neurology residency

BACKGROUND

Physicians often do not have good understanding of research methodology. Unfortunately, the mechanism to achieve this important competency in a busy neurology residency program remains unclear. We tested the value and degree of acceptance by neurology residents of a multimodal educational intervention that consisted of biweekly teaching sessions in place of an existing journal club, as a way to provide formal training in research and statistical techniques.

METHODS

We used a pre- and post-test design with an educational intervention in between using neurology residents at the University of Iowa as subjects. Each test had 40 questions of research methodology. The educational intervention consisted of a biweekly, structured, topic-centered, research methodology-oriented elective seminar following a year-long predefined curriculum. An exit survey was offered to gather resident's perceptions about the course.

RESULTS

While a majority of residents agreed that the intervention enhanced their knowledge of research methodology, only 23% attended more than 40% of the sessions. There was no difference between pretest and post-test scores (p = 0.40).

CONCLUSIONS

Our experience suggests that, in order to accomplish the Accreditation Council for Graduate Medical Education goals regarding increasing competency of residents in knowledge about research methodology, a major restructuring in the neurology residency curriculum with more intense formal training would be necessary.

Lysosomal malfunction accompanies alpha-synuclein aggregation in a progressive mouse model of Parkinson's disease

We have detected granular and filamentous inclusions that are alpha-synuclein- and ubiquitin-immunoreactive in the cytoplasm of dopaminergic and cortical neurons of C57/black mice treated chronically with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and probenecid. The immunoreactive aggregates only become evident several weeks after large-scale dopaminergic cell death and a downregulation of alpha-synuclein gene expression. Numerous lipofuscin granules accumulate alpha-synuclein in the nigral and limbic cortical neurons of treated mice. These data provide evidence that insoluble proteins, such as alpha-synuclein, build up as granular and filamentous inclusions in dopaminergic neurons that survive the initial toxic MPTP insult. They further suggest that defective protein degradation rather than altered gene expression underlies deposition of alpha-synuclein and that abundant lysosomal compartments are present to seal off the potentially toxic material.