Debates on Intracranial artery disease (ICAD) at ISC 2012, and imaging

Lessons from Sampris-- Wingspan stent trial was stopped due to more deaths in stent group.  However, issues that were brought out include that sites had inexperienced interventionalists with an average enrollment of 2 per site, total enrollment fairly small, plus criteria for enrollment was not (necessarily) ideal since we don't know who best candidates are.  One comment was that randomized trials if done too early (as here) retard innovation.

 

An  important finding of Sammpris ties in with the theme of the year, which is that medical management has improved. 2 year mortality of ICD declined from 20 percent in earlier trials to about 12 % in Sammpris.  The putative hero is aggressive 2011 medical management, with all it entails for tighter blood pressure control, tighter LDL-c reduction, attention to so called minor risk factors including metabolic syndrome, HDL, CRP and others.

 

One woman commented on her own "no metal " experience with angioplasty and made a case for a clinical trial with "no metal."  The main risk of failure was not seen in her series of series. (Thanh Nguyen).  Thereupon a discussion ensued about whether or not brain arteries are like coronary arteries where we already have learned so much.  Brain arteries have no external lamina are smaller caliber and more prone to perforation. 

 

Tom Brott opined that future trials of ICAD will need to compare procedures with new "best medical."

 

IMAGING

 

Debate again, is over what is best imaging protocol for stroke.  Data was presented that CT-P does NOT improve 90 day modified Rankin scores over regular noncontrast CT as a stratifier.  CT-P does add to time to catheter.  Time to order is a major delay point.  Whatever is used should be comfortable at facility. 

 

Purpose of extra procedures (advanced MRI or CT) is to exclude futile procedures and cases likely to hemorrhage (do no harm) as well as tell anatomy of occlusion to guide procedure. D-P mismatch, as last year, is not key, core infarct size is much more important (can tell best on MRI diffusion studies or possibly CBV). Exceptions are malignant pattern (see DEFUSE trial)  Evaluation of collateral flow is gaining prominence. One speaker commented that they still intervene on the ten percent that imaging says are futile.