Symptomatic atherosclerotic plaque progression in a first-generation carotid stent: management and 5-year clinical and imaging outcome—a case report

Abstract

Background Restenosis in first-generation (single-layer, nitinol) carotid stents (FGS) is believed to represent an exaggerated healing response of (neo)intimal hyperplasia (NIH) formation. Rather than NIH, we describe symptomatic in-FGS unstable plaque (neo)atherosclerosis mandating re-revascularization. To halt continued plaque evolution, we propose a novel treatment strategy involving a micronet-covered stent to sequestrate the plaque from the vessel lumen. A durable long-term result is documented using multi-modal imaging. Case summary With a seemingly optimal result of FGS (Precise) symptomatic carotid lesion revascularization followed by optimal medical therapy, a late (≥3 years) progressive ISR arose. At year 11, crescendo ipsilateral transient ischaemic attacks occurred. Angiography showed an ulcerated tight lesion throughout stent length. Intravascular ultrasound (IVUS) revealed thin-cap fibroatheroma. Re-intervention was performed under distal protection. Undersized balloon predilatation caused symptomatic no-flow, and aspiration catheter was used to reduce the filter load. A micronet-covered stent (CGuard) was implanted and post-dilated to ensure full lumen gain; IVUS confirmed complete plaque sequestration. The optimal anatomic result remained unchanged throughout 5 years (ultrasound and computed tomography verification); this was accompanied by clinical cure. Discussion This is the first demonstration of in-FGS (neo)atherosclerosis resolution using a micronet-covered stent to sequestrate and insulate the atherosclerotic plaque. We show that ISR may be underlined by late atherosclerotic plaque progression via the FGS single-layer stent struts that may show vulnerable plaque phenotype and may be associated with cerebral ischaemia. The anatomically and clinically effective exclusion of the atherosclerotic plaque by a micronet-covered stent enabled lasting, optimal endovascular reconstruction and clinical cure.

Diabetes Mellitus and Clinical Outcomes in Carotid Artery Revascularization Using Second-Generation, MicroNet-Covered Stents: Analysis from the PARADIGM Study

“…Recent data suggest that a proportion of "in-stent restenoses" in single-layer (conventional) stents may represent plaque progression into the lumen [12]; an adverse phenomenon is amenable to elimination with MCS [11,12]. This is important because "in-stent restenosis" is associated with an increased risk of recurrent stroke [24,25], and it poses a significant management challenge [12,37,38]. EDV (m/s ± SD) 0:22 ± 0:18 0:21 ± 0:09 0.74 RICA: right internal carotid artery; QCA: quantitative comparative analysis; PSV: peak systolic velocity; EDV: end diastolic velocity; EPD: embolic protection device.…”

“…The unwanted phenomenon of plaque prolapse is not eliminated using closed-cell single-layer stents [ 31 , 32 ]. In contrast, it can be effectively abolished with MCS use [ 11 , 12 ]. This may be clinically important as a large proportion of peri- and postprocedural CAS complications is lesion-level based [ 11 ].…”

“…In conventional carotid stents, this mid/long-term complication may not be clinically benign [ 35 ], and it importantly contributes to CAS overall adverse events in relation to CEA [ 36 ]. Recent data suggest that a proportion of “in-stent restenoses” in single-layer (conventional) stents may represent plaque progression into the lumen [ 12 ]; an adverse phenomenon is amenable to elimination with MCS [ 11 , 12 ]. This is important because “in-stent restenosis” is associated with an increased risk of recurrent stroke [ 24 , 25 ], and it poses a significant management challenge [ 12 , 37 , 38 ].…”

“…The threshold for suspected restenosis on DUS follow-up was peak-systolic velocity of at least 175 cm/s [ 16 ]. Suspicion of in-stent restenosis (ISR) triggered invasive angiographic verification [ 12 ].…”

“…We hypothesized that the dual-layer MicroNet-covered carotid stent use in CAS in primary and secondary stroke prevention in diabetic patients might offset—by plaque sealing with inhibition of cerebral embolism and the stented lumen optimization [ 8 , 12 ]—the impact of DM on adverse clinical events and restenosis rate by 12 months.…”