Optical Coherence Tomography Findings in Bioresorbable Vascular Scaffolds Thrombosis

Abstract

Background— Everolimus-eluting bioresorbable vascular scaffolds have been developed to improve late outcomes after coronary interventions. However, recent registries raised concerns regarding an increased incidence of scaffold thrombosis (ScT). The mechanism of ScT remains unknown. Methods and Results— The present study investigated angiographic and optical coherence tomography findings in patients experiencing ScT. Fifteen ScT (14 patients, 79% male, age 59±10 years) occurred at a median of 16 days (25%–75% interquartile range: 1–263 days) after implantation. Early ScT (<30 days) occurred in 8 cases (53%). Possible causal factors in these patients included insufficient platelet inhibition in 2 cases and procedural factors (scaffold underexpansion, undersizing, or geographical miss) in 4 cases. No obvious cause could be found in 2 early ScT. In late (>1 month) and very late (>1 year) ScT (respectively, 5 and 2 cases), 5 scaffolds showed intimal neovessels or marked peristrut low-intensity areas. Scaffold fractures were additionally found in 2 patients, and scaffold collapse was found in 1 patient with very late ScT. Extensive strut malapposition was the presumed cause for ScT in 1 case. One scaffold did not show any morphological abnormality. Thrombectomy specimens were analyzed in 3 patients and did not demonstrate increased numbers of inflammatory cells. Conclusions— The mechanisms of early ScT seem to be similar to metallic stents (mechanical and inadequate antiplatelet therapy). The predominant finding in late and very late ScT is peristrut low-intensity area.

Bioresorbable vascular scaffold thrombosis in a consecutive cohort of 550 patients

“…Our data supports this observation, with a median interval from implantation to definite and probable scaffold thrombosis of 25.5 days and 42% of all thromboses occurring within the first week after implantation. The most important procedural factor may be scaffold underexpansion . In our cohort, predilatation had been performed in all lesions with later thrombosis, but the rate of NC balloon postdilatation in our overall cohort, while not different in patients with and without BVS thrombosis, was only 63% (similar to the GHOST‐EU registry).…”

Three‐year clinical outcomes of patients treated with everolimus‐eluting bioresorbable vascular scaffolds: Final results of the ABSORB EXTEND trial

“…Most of the present knowledge is based on retrospective analysis from case reports using intravascular imaging, especially OCT. Among the postulated causes the most frequent observed are: (1) strut malapposition (either persistent or late acquired); (2) late device discontinuity, which is a programmed phenomenon in the bioresorption process of the polymeric device; (3) peri strut low‐intensity area on OCT; (4) delayed vessel healing, and (5) neoatherosclerosis …”

“…Kaplan-Meir survival curves of MACE (panel A) and target-vessel failure (panel B) persistent or late acquired); (2) late device discontinuity, which is a programmed phenomenon in the bioresorption process of the polymeric device; (3) peri strut low-intensity area on OCT; (4) delayed vessel healing, and (5) neoatherosclerosis [22][23][24][25]. Dual antiplatelet therapy (DAPT) has a key importance in the prevention of thrombotic events after BVS.…”

A case report of a recurrent early and late Bioresorbable vascular scaffold thrombosis: serial angiography and optical coherence tomography findings

“…However, with bioresorbable vascular scaffolds (BVSs), there is some concern about an increased rate of scaffold thromboses (ScTs) [4]. Optical coherence tomography (OCT) imaging is instrumental in identifying the mechanisms of STs as well as ScTs [5]. Several case reports have revealed the mechanism of ScTs using OCT.…”