In our cover story this issue, we examine some novel innovations in the cath lab, several of which revolve around improving outcomes in drug-eluting stent (DES) implantation.
When DES appeared on the U.S. market, their utilization skyrocketed. Years later, however, researchers began to examine risks associated with DES, including restenosis and stent thrombosis. While newer generation stents, with lower profiles and unique drug and polymer combinations, have demonstrated superiority over first-generation DES, there are still improvements to be made in the way stents are implanted and in lesion and patient selection.
Now, interventionalists are seeking imaging modalities that help to better define lesion characteristics, as well as better determine accurate stent implantation. Intravascular ultrasound (IVUS) is well validated in the literature as a tool to help ensure proper stent expansion and apposition, two factors that have been indicated in the cause of stent thrombosis. Virtual histology can be combined with IVUS as a means to characterize plaque composition.
Two newer approaches for intravascular imaging are near-infrared spectroscopy (NIRS) and optical coherence tomography (OCT). While these technologies are decades old, it is only recently that the FDA has approved specific products for use in the cath lab.
By characterizing plaque, NIRS can pinpoint troublesome lipid cores. What to do with this information is the subject of much research. OCT is helping researchers better understand the vascular response to stent implantation, especially as indications for stenting expand to more complex arterial realms.
Such tools can lead the way to individualized treatment, particularly when OCT imaging can show at six months post-implantation the amount of strut coverage. Clinicians can use this information to determine whether to be more aggressive with antiplatelet medication or stay the course.
Reimbursement for these adjunctive imaging technologies is low or nonexistent, and that could hurt their chances for widespread adoption. But all it takes is a breakthrough trial like FAME to propel a new technology into the mainstream. Stay tuned.