Late stent thrombosis six months after ultrathin-strut covered stent implantation in lesion with calcified nodule

Abstract

A 72-year-old woman undergoing hemodialysis presented with effort angina pectoris due to severe stenosis with calcified nodules in the right coronary artery. Percutaneous coronary intervention was performed using an excimer laser coronary angioplasty and an ultrathin-strut covered stent (CS) was implanted due to coronary perforation. An additional durable-polymer everolimus-eluting stent (DP-EES) was implanted because of protrusions in the proximal edge of the CS. However, late stent thrombosis occurred six months after ultrathin-strut covered stent implantation for a calcified nodule. After thrombus aspiration, intravascular imaging analyses revealed that the struts within the CS were fully covered with thick neointimal hyperplasia. In contrast, half of the struts in the DP-EES were uncovered and some struts were malapposed. In this case, we speculated that the cause of the current late stent thrombosis was dispersion of the thrombi formed at the uncovered with malapposed sites in the DP-EES into a severe stenosis caused by neointimal hyperplasia in the CS. Neointimal hyperplasia occurs at the edge of the CS, a CS should be implanted locating its edge on the site with less plaque.

Learning objectives

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  To evaluate the mechanism of late stent thrombosis after ultrathin strut-covered stent implantation for lesions with calcified nodules.
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  To discuss the optimal covered stent placement locating its edge on the site with less plaque.
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  To recognize that introduction of an ultrathin-strut covered stent for lesions with calcified nodules requires careful consideration.