Very Early Progression of an In-Stent Calcified Nodule 2 Weeks After Drug-Eluting Stent Implantation in the Calcified Lesion.

In-stent calcified nodules (CNs) are one of the mechanisms of in-stent restenosis, but their underlying cause has not been elucidated. We report a case of a patient with early stent thrombosis due to an in-stent CN only 2 weeks after drug-eluting stent implantation. The fact that the in-stent CN was detected only 2 weeks after the initial percutaneous coronary intervention means that the underlying mechanism was the progression of the CN, indicating that in-stent CNs can occur even in the subacute phase. After percutaneous coronary intervention for a severe calcified lesion, very early progression of CNs can occur, and they require close follow-up and intensive antiplatelet therapy.