Testing devices for the prevention and treatment of stroke and its complications

We are entering a challenging but exciting period when many new interventions may appear for stroke based on the use of devices. Hopefully these will lead to improved outcomes at a cost that can be afforded in most parts of the world. Nevertheless, it is vital that lessons are learnt from failures in the development of pharmacological interventions (and from some early device studies), including inadequate preclinical testing, suboptimal trial design and analysis, and underpowered studies. The device industry is far more disparate than that seen for pharmaceuticals; companies are very variable in size and experience in stroke, and are developing interventions across a wide range of stroke treatment and prevention. It is vital that companies work together where sales and marketing are not involved, including in understanding basic stroke mechanisms, prospective systematic reviews, and education of physicians. Where possible, industry and academics should also work closely together to ensure trials are designed to be relevant to patient care and outcomes. Additionally, regulation of the device industry lags behind that for pharmaceuticals, and it is critical that new interventions are shown to be safe and effective rather than just feasible. Phase IV postmarketing surveillance studies will also be needed to ensure that devices are safe when used in the ‘real-world’ and to pick up uncommon adverse events

How I Interpreted the Randomised Trials of Carotid Angioplasty/stenting versus Endarterectomy

AbstractCarotid endarterectomy (CEA) for carotid stenosis is effective in preventing ipsilateral carotid territory ischaemic stroke. Paradoxically however, it causes a stroke (the event it is trying to prevent) in about 5% or more of cases. If carotid angioplasty/stenting (CAS) is to have a place in the management of patients with carotid stenosis (beyond those who are not suitable for CEA), it has to demonstrate that it is also effective and safe.Limited data from 12 randomised trials comparing CAS with CEA (the current “gold standard”) in a total of 3227 patients with carotid stenosis (90% symptomatic) question the safety of CAS and suggest that it may cause more non-fatal, procedural strokes than CEA despite similar mortality rates and a much lower immediate local complication rate (eg cranial neuropathy). However, the published trials are rather heterogeneous (clinically and methodologically), none is large enough to provide robust and convincing data and long-term follow-up is very limited. Accordingly, it remains unknown whether CAS is effective in preventing recurrent stroke among patients with carotid stenosis, or whether it is safe.More data (from at least another 3,000 patients) are needed from the ongoing randomised trials before it can reliably be concluded whether CAS is inferior to, non-inferior to, or more effective than, CEA. More importantly, it will be possible to determine which patients should be treated preferentially with CAS, which patients with CEA, and which patients should not undergo either revascularisation procedure