Optical coherence tomography in bioabsorbable stents: mechanism of vascular response and guidance of stent implantation.

Fully biodegradable L-polylactic acid stents (biodegradable vascular scaffold, BVS), the latest breakthrough in the area of coronary implants, entered clinical trials in 2005 and became commercially available in 2011. Optical coherence tomography (OCT) was used from the first implants to study the vessel wall response and the timing of the resorption process in man. Analysis of BVS with OCT has several advantages over that of metallic stents. BVS polymeric struts are transparent to the light so that scaffold integrity, apposition to the underlying wall, presence of thrombus and hyperplasia, and changes in the strut characteristics over time can be easily studied. We present a comprehensive review of the findings OCT provided when used as a research tool in serial examination up to five years for investigation of the mech anism of resorption, neointimal coverage, shrinkage and late lumen enlargement. We also report our experience with OCT in 47 lesions of various complexity as a practical means of percutaneous coronary intervention guidance during BVS implantation.