A case report of very late thrombosis of coronary bare-metal stent 10 years after stenting

Bare-metal stent thrombosis two decades after stenting

Very late bare-metal stent (BMS) thrombosis is unusual in clinical practice. To the best of our knowledge, the latest that the thrombosis of a BMS has been reported is 14 years after implantation. Here, we describe a case of BMS thrombosis that occurred two decades after stenting. A 68-year-old male patient was admitted with acute anterior myocardial infarction. This patient had a history of BMS implantation in the left anterior descending coronary artery (LAD) 20 years previously. Immediate coronary angiography demonstrated acute thrombotic occlusion of the stent in the LAD. With this case, we are recording the latest reported incidence of BMS thrombosis after implantation.

Renal dysfunction and atherosclerosis of the neointima following bare metal stent implantation

BACKGROUND

Recently, neoatherosclerosis within the neointima after bare metal stent (BMS) implantation, which could cause late restenosis and very late stent thrombosis, has been a cause of concern. Renal dysfunction has been related to late cardiovascular events after coronary intervention. The present study was conducted focusing on the relationship between renal dysfunction and neointimal tissue characteristics with BMS restenosis using integrated backscatter intravascular ultrasound (IB-IVUS).

METHODS

We prospectively performed IB-IVUS in 80 consecutive patients requiring target lesion revascularization after BMS implantation; the patients were divided into two groups according to the estimated glomerular filtration [eGFR: ≥60 (n = 49) and <60 ml/min/1.73 m(2) (n = 31)].

RESULTS

Patients with eGFR <60 ml/min/1.73 m(2) had a significantly higher percentage of lipid tissue volume within the neointima and a lower percentage of fibrous tissue volume than those with eGFR ≥60 ml/min/1.73 m(2) (23.2 ± 9.4 vs. 18.0 ± 7.0%, p = 0.005, and 75.3 ± 9.3 vs. 80.4 ± 7.0%, p = 0.007, respectively). Using logistic regression analysis, eGFR <60 ml/min/1.73 m(2) and duration from stent implantation ≥48 months were independent predictors of increased lipid tissue volume within the neointima (odds ratio, 3.93; 95% confidence interval, 1.15-13.46, p = 0.03, and odds ratio, 7.56; 95% confidence interval, 2.02-28.30, p = 0.003, respectively).

CONCLUSIONS

Lower eGFR levels were associated with greater lipid tissue volume within the neointima after BMS deployment, suggesting the development of atherosclerosis. Renal dysfunction may affect neointimal tissue characteristics and thus leading to an increased risk of late stent failure.

Very late thrombosis in a bare metal stent: mechanistic analysis from optical coherence tomography

Recent publications have emphasized the concept that restenosis of a bare metal stent (BMS) is not as clinically benign as previously believed. We present a case of very late stent thrombosis 9 years after implantation of a BMS is described. Optical coherence tomography shows plaque rupture in the stent. These findings suggest that the formation and progression of a neoatheroma over a previously healed intrastent vascular intima may represent a "new" mechanism for stent thrombosis. Evidence from the current case supports this hypothesis.