Characteristics of stent thrombosis in bifurcation lesions analysed by optical coherence tomography

Aims: This work aimed to investigate a cohort of patients presenting with stent thrombosis (ST) explored by optical coherence tomography (OCT) to identify the underlying mechanical abnormalities in case of bifurcation lesions. Methods and results: The PESTO study was a prospective national registry involving 29 French catheterisation facilities. Patients with acute coronary syndromes were prospectively screened for presence of definite ST and analysed by OCT after culprit lesion reopening. The cohort involved 120 subjects, including 21 patients (17.5% of the global PESTO group; median age: 62.6 yrs; 76% male) with bifurcation lesions. The clinical presentation was acute or subacute ST in 34%, late ST in 5% and very late ST in 62% of the patients. The main underlying mechanisms were strut malapposition in 33%, stent underexpansion in 19% and isolated strut uncoverage in 19% of the cases. The proximal main branch was involved in 71%, distal main branch in 52% and jailed side branch in 5% of the patients. Conclusions: In this cohort, bifurcation lesions represented a limited number of all ST cases. Different sections of the bifurcation could be involved. Although the underlying mechanisms were various, strut malapposition was the most frequently observed cause.