Shedding Light on Bioabsorbable Stent Struts Seen by Optical Coherence Tomography in the ABSORB Trial

Abstract

Optical coherence tomography (OCT) is an emerging intracoronary imaging technology that obtains depth-resolved images of light backscattered from the coronary wall with an axial resolution of ≈10 μm. First demonstrated in 2001 in patients,1 intracoronary OCT is now commercially available and is beginning to be adopted in cardiac catheterization laboratories worldwide. An important application of OCT is the investigation of intracoronary stents; ≈100 articles have been published over the past 5 years in which OCT was used for this purpose. OCT is well suited for such studies because (1) its contrast and resolution enable delineation of fine details including device and arterial wall structures; (2) stent healing occurs near the luminal surface, where OCT is most effective; and (3) relative to other imaging modalities, OCT has fewer imaging artifacts that interfere with the appearance of stent struts and surrounding tissues. Article see p 2288 Recently, researchers have found that OCT may also be well suited for investigating the fate of bioabsorbable stents, including bioabsorbable vascular scaffolds (BVS).2,–,9 These new devices are of particular interest because they offer the potential to facilitate coronary revascularization while subsequently being dissolved and assimilated into the artery wall. Resorption in this manner may overcome many of the limitations of bare-metal and drug-eluting stents by leaving behind a revascularized coronary artery without any residual “foreign” material that can promote restenosis or precipitate late stent thrombosis. Given the recent introduction of new generations of bioabsorbable stents, it is critical to understand and monitor …