Publication of the Flow Diversion in the Treatment of Intracranial Aneurysm Trial (FIAT): a randomized care trial and registry
This month the results of the Flow Diversion in the Treatment of Intracranial Aneurysm Trial (FIAT) were published ahead-of-print in the Journal of Neurosurgery. From 2011 to 2015, 78 patients were randomized between flow diversion and standard management, and 34 patients received flow diversion within a registry at 3 Canadian hospitals. Primary safety and efficacy outcomes were death or dependency (mRS > 2) at 3 months and angiographic occlusion at 3-12 months and independence, respectively. Both Silk (55%) and Pipeline (45%) were used. The study was halted for safety concerns after 16% of patients that received a flow diverter as part of the randomized group and registry were dead or dependent after 3 months.
In an era of deliberate off-label use of flow diverters, the study is most timely and will spark some debate. The trial illustrates some of the difficulties in producing a high level of evidence data pertinent to flow diverters. The high number of patients (30%) enrolled in the registry shows that for many challenging aneurysms there is no true equipoise. Testing for platelet inhibition was not required. There is, however, growing evidence that testing for platelet inhibition is critical, while the ideal test, threshold, and alternative antiplatelet regimen are yet to be determined. Aneurysms that failed flow diversion were truly daunting and included large and giant posterior circulation lesions, a large middle cerebral aneurysm, and a ruptured aneurysm. Open surgical therapy was not chosen for any of the aneurysms in the standard management group.
The full text can be accessed here.