A 59-year-old man presented to our department with one day history of intermittent angina and a high sensitivity troponin measurement was elevated. He received stent implantation with a 4.5 x 16 mm bare metal stent (BMS) at the proximal portion of the ectatic right coronary artery (RCA) 3 years ago. Urgent coronary angiography (CAG) demonstrated the severe stenosis in the distal RCA with patent of implanted BMS (Fig. 1A). The non flow-limiting nature of the lesion and the consideration of using a drug-eluting stent led to assessment with optical coherence tomography (OCT) (Video 1). OCT demonstrated that distal reference lumen and external elastic lamina (EEL) diameter of 4.67 mm and 5.20 mm, respectively (Fig. 1B). OCT also showed a minimal lumen area of 3.32 mm2 (Fig. 1C) and proximal reference lumen and EEL diameter of 3.91mm and 4.65mm, respectively (Fig. 1D).
With the OCT assessment, intervention strategies were planned as follows,
i) A selection of a 4.0 x 24 mm drug-eluting stent (DES).
ii) Stent implantation with high pressure by stent balloon.
iii) Postdilation with 5.0 mm noncomliant balloon (NC) with high pressure in distal portion of implanted DES including stent edge.
The OCT assessment led to predilation with a 3.0 x 15 mm balloon, and a 4.0 x 24 mm bioabsorbable polymer everolimus-eluting stent (SYNERGYTM, Boston Scientific, USA) implantation at 16 atmosphere, followed by postdilation with a 5.0 x 12 mm NC balloon at up to 18 atmosphere in the distal portion of implanted DES. Repeated OCT assessment demonstrated a minimal stent area of 11.92 mm2 (Figure 1E), excellent stent expansion, and good strut apposition without edge dissection (Video 2). Final CAG showed good distal flow without residual stenosis.
Percutaneous coronary intervention (PCI) with DES for ectatic coronary artery is challenging due to the stent optimization. Our experience highlights the important role OCT plays in the stent optimization for ectatic vessel.
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