Endothelialisation of 3rd generation orsiro hybrid drug eluting stents at 6 months follow-up: analysis by optical coherence tomography

Abstract

Background: Since the introduction of 2rd generation DES and dual antiplateled therapy (DAPT) stent thrombosis is a rare complication of PCI. DAPT is recommended for 6-12 months after DES implantation. Long term DAPT involves the risk of bleeding events, shorter DAPT duration would be beneficial. The Hybrid Orsiro DES presenting a new concept by combination of passive and active components. The passive coating seals the stent and minimizes tissue interaction. The active component is a bioresorbable polymer matrix combined with sirolimus. Stent thrombosis correlates to mal-apposition and incomplete stent coverage. IVUS is not able to monitor strut coverage due to lack of resolution. Intracoronary optical coherence tomography (OCT) is able to solve this shortcoming. Stent endothelialisation is associated to OCT strut coverage although not fully identical. We tested, whether the Orsiro Hybrid DES has no strut malapposition related to the polymer/drug combination as measured by OCT after 6 months. Methods: Patients (n=13, with n =21 Orsiro Hybrid-DES) were readmitted for routine coronary angiography and OCT 6 months after PCI. (Figure 1) Stent struts (n= 702) were classified according to previously described criteria (mean ± SEM): type I (embedded struts with>0.15 mm neointima): 25.5±11.2%; type II (embedded struts with< 0.15mm neointima): 49.9±21.5%; type IIIa (protruding/covered struts): 19.6±9.7%; type IIIb (protruding/ uncovered): 3.3±3.1%; type IV (malapossed/uncovered struts): 1.7±3.1%. ![Figure][1] Figure 1 Conclusion: The data support the hypothesis that Orsiro Hybrid DES achieved nearly complete strut coverage as measured by OCT at 6 months. Therefore an early termination of DAPT could be an option to prevent major bleeding events without increasing the risk of acute stent-thrombosis. [1]: pending:yes