When it comes to clinical trials assessing devices, the evidence sometimes seems a step behind contemporary practice. That was the upshot of several studies presented at the European Society of Cardiology Congress in Munich this past week.
Take, for instance, results from the TREVO and SWIFT trials. In TREVO, researchers compared the efficacy and safety of the Trevo Retriever with its predecessor, the FDA-approved Merci Retriever, in patients who have had large vessel occlusion strokes and are ineligible for medical therapy. Stryker Neurovascular makes both models. The results showed the Trevo Retriever was superior.
In SWIFT, the FDA-approved Solitaire Flow restoration device (Covidien) took on the Merci Retrieval System as a treatment in patients with ischemic stroke due to large intracranial vessel occlusion. Results favored Solitaire Flow, which had substantially better angiographic, safety and clinical outcomes.
The Trevo Pro Retriever received the FDA’s blessing on Aug. 15, according to Stryker. Where does that leave Merci?
The PROTECT trial also appeared to be the victim of technology’s rapid evolution. In PROTECT, researchers compared the incidence of stent thrombosis between the Endeavor zotarolimus-eluting stent (Medtronic) and the Cypher sirolimus-eluting stent (Cordis, a Johnson & Johnson company). Researchers found no evidence of superiority in definite and probable stent thrombosis rates between the two types of stents at three years.
Lancet simultaneously published PROTECT results and an accompanying editorial. The editorial writers observed that newer devices have supplanted Endeavor and Cypher, with the older models no longer favored by physicians. They wrote that the findings still had value for cardiologists whose patients received the stents, though.
Better understanding of outcomes with older technologies is useful. But with technology evolving at a quicker pace, it may become increasingly challenging to design high-quality trials with sufficient follow-up that still offer results that reflect contemporary practice.
Cardiovascular Business, editor