TRANSFORM OCT TRiple Assessment of Neointima Stent FOrmation to Reabsorbable polyMer With Optical Coherence Tomography

During the last decade a considerable clinical experience has been accumulated with the use of drug eluting coronary stents with durable polymers, that permanently cover the metallic stent scaffold, allowing the local delivery of anti-restenotic agents. However durable polymers have been associated with an increased risk of late and very late stent thrombosis and the anticipated development of in stent neo-atherosclerosis. Since permanent polymer coatings may have pro-inflammatory effects, with delayed healing and prolonged endothelial dysfunction, current research on DES has focused on the use of biodegradable polymer coatings, which disappear after a short period of drug-release (3-4 months). Current clinical guidelines recommend at least 6-12 months of dual antiplatelet therapy (DAPT) after DES implantation,in order to prevent ST. Recent data obtained by pooled analyses of ZES, support a significant reduction of the DAPT to the same range used with bare metal stents. The substantial delays in DES healing observed from multiple human pathology series and in-vivo studies using Optical Coherence Tomography (OCT) were not assessed as risk factors for prolonged used of DAPT. However different patient cohorts might have different responses to stent implantation. In addition, there is no comparative evidence on long term development of neo-atherosclerosis in bioabsorbable versus permanent polymer DES. OCT allows precise assessment of stent strut apposition and coverage and accurate measures of different tissue components of neoatherosclerosis. This study is the first attempting to characterize the early and late vascular responses to novel bioabsorbable polymer EES (SYNERGY™) compared with a permanent polymer benchmark novel generation ZES (RESOLUTE INTEGRITY™) .The stent comparator has been selected due to the large use across the interventional cardiology community and the recent approval from European Regulators Authorities to update the CE (Conformité Européenne) mark labeling to only one-month duration of dual anti-platelet therapy.