Vascular Wall Imaging of Vulnerable Atherosclerotic Carotid Plaques: Current State of the Art and Potential Future of Endovascular Optical Coherence Tomography

SUMMARY: As stroke is one of the leading causes of death and long-term morbidity worldwide, the research community has studied cardiac embolic sources, as well as vessel wall pathologies. For the latter, attention has been focused on defining morphologic tissue features associated with catastrophic events stemming from the carotid artery. Multiple noninvasive imaging modalities are currently being used to image and classify carotid atherosclerotic plaques, such as MR imaging, CT, and sonography, in an effort to provide clinically relevant predictive metrics for use in patient risk stratification and to define appropriate treatment options. This article compares and contrasts these existing clinical imaging modalities along with discussion of a new endovascular technique originally developed for cardiology, OCT, with which 3D comprehensive high-resolution images of the arterial wall can be acquired. ABBREVIATIONS: AHA ϭ American Heart Association; CE ϭ contrast-enhanced; CI ϭ confidence interval; HR ϭ hazard ratio; MDCTA ϭ multidetector row CT angiography; MRDTI ϭ MR direct thrombus imaging; OCT ϭ optical coherence tomography; TOF ϭ time-of-fligh

Time for a Time Window Extension: Insights from Late Presenters in the ESCAPE Trial.

BACKGROUND AND PURPOSE: The safety and efficacy of endovascular therapy for large-artery stroke in the extended time window is not yet well-established. We performed a subgroup analysis on subjects enrolled within an extended time window in the Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE) trial. MATERIALS AND METHODS: Fifty-nine of 315 subjects (33 in the intervention group and 26 in the control group) were randomized in the ESCAPE trial between 5.5 and 12 hours after last seen healthy (likely to have groin puncture administered 6 hours after that). Treatment effect sizes for all relevant outcomes (90-day mRS shift, mRS 0-2, mRS 0-1, and 24-hour NIHSS scores and intracerebral hemorrhage) were reported using unadjusted and adjusted analyses. RESULTS: There was no evidence of treatment heterogeneity between subjects in the early and late windows. Treatment effect favoring intervention was seen across all clinical outcomes in the extended time window (absolute risk difference of 19.3% for mRS 0-2 at 90 days). There were more asymptomatic intracerebral hemorrhage events within the intervention arm (48.5% versus 11.5%, CONCLUSIONS: Patients with an extended time window could potentially benefit from endovascular treatment. Ongoing randomized controlled trials using imaging to identify late presenters with favorable brain physiology will help cement the paradigm of using time windows to select the population for acute imaging and imaging to select individual patients for therapy

The future of endovascular treatment: Insights from the ESCAPE investigators.

The ESCAPE trial demonstrated strong morbidity benefit and mortality reduction for endovascular stroke treatment. Following the release of the main results, the ESCAPE trial investigators convened at a 2-day close-out meeting in March 2015 in Banff, Alberta, Canada. Meeting discussions focused on system implications, procedural characteristics, and future directions. We report the proceedings of the meeting, which provide insights from the trialists into the issues of generalizability, treatment limitations, as well as future directions and opportunities in stroke care optimization