Case 1
A 48-year-old female presented with an inferior STEMI. She had undergone PCI and implantation of a drug eluting stent (DES) to the proximal right coronary artery (RCA) for an AMI five years earlier (Fig 1 A, B). The angiogram revealed a thrombotic occlusion (TIMI 0 flow) due to very late ST of the previously implanted DES. The angiogram indicated a large thrombus burden. A bolus of intracoronary eptifibatide was administered. After pre-dilatation using a 2.0 mm non-compliant (NC) balloon and thrombectomy (ASAP LP, Merit Medical, U.S.A.), we were not able to completely restore flow (TIMI 1) (Fig 1 C). The OCT investigation (Dragonfly, Abbott Vascular, Santa Clara, California) indicated presence of large amount of white and red thrombus and a previously implanted stent, which appeared under-expanded (Fig 2 A). Additionally, we observed excessive neointima formation. We consecutively implanted a 3.5x28 mm DES (Xience Sierra, Abbott Vascular, Santa Clara, CA) at nominal pressure (12 atm), which immediately established TIMI 3 flow and lead to complete ST-segment resolution (Fig 1 D). Stent-optimization was postponed, and the patient was treated with dual antiplatelet therapy and therapeutic dosage of dalteparine. Five days later, OCT-guided stent optimization was performed. Small amounts of residual thrombus were still present, and we observed under-expansion of the initial stent as well as under-expansion and malapposition of the newly implanted stent (Fig 2 B). A 4.0 mm (NC) balloon (Easy T NC, SIS Medical Switzerland, Frauenfeld Switzerland) was used (inflation pressure 25 atm), which corrected stent under-expansion and improved stent apposition, as confirmed by angiography and OCT (Fig 1 E, F; Fig 2 C). Coronary flow was not impacted (final TIMI flow 3). Our patient was discharged after 6 days. She recovered well and her follow-up echocardiogram revealed an only mildly reduced left ventricular ejection fraction (LVEF 50 %).