Underlying Mechanisms of Second-Generation Drug Eluting Stent Thrombosis: An Optical Coherence Tomography Study

Optimal percutaneous coronary intervention (PCI) for the treatment of stent thrombosis (ST) depends on the mechanism of the ST. Since conventional invasive angiography has limited value for the identification of the underlying aetiology, intravascular imaging is particularly important.

To demonstrate the optical coherence tomography (OCT) findings in patients presenting with early, late, and very late drug-eluting ST.

Angiography and OCT images of patients with ST were reviewed. OCT findings, including malapposition, neoatherosclerosis, neointimal hyperplasia, stent expansion index, minimal lumen area, and stent edge disease, were assessed.

There were six patients with early ST and 68 patients with late ST (28 late ST and 40 very late ST). Among patients with early ST, there were four cases with stent edge dissection, one case with significant tissue/thrombus prolapse, and there was no plausible cause of ST in one patient. There was no significant difference between patients with late and very late ST in terms of clinical features. The mechanism of ST in the overall patient group was neoatherosclerotic plaque rupture (42.6%), neointimal erosion (20.5%), stent-edge disease (22.0%), and malapposition/uncovered strut (10.2%). No plausible pathology of ST (4.4%) was detected in three patients. The most common OCT findings were neoatherosclerosis (70.4%), stent-edge disease (61.4%), underexpansion (55%), and malapposition/uncovered strut(48%).

OCT is a feasible and safe procedure that clearly identifies the underlying aetiology in the majority of patients with ST. Furthermore, OCT is of clinical importance regarding individualizing and optimizing the PCI procedure.