LAUSR

A 48-year-old man with acute coronary syndrome was transferred to our hospital for primary percutaneous coronary intervention. He underwent urgent balloon angioplasty for in-stent restenosis in the distal right coronary artery (RCA) and drug-eluting stent implantation (4.0 × 33 mm) across the coronary artery aneurysm (CAA) in the mid RCA (Fig. 1a, the upper panels). Subsequently, procedure to exclude CAA was intended since the CAA was proven to be enlarged within three years by referring previous angiogram. While shortest length of the covered stent (CS) available in Japan at that moment was 16 mm, the distance between two right ventricular branches (RVBs) originating at proximal and distal sides of the CAA was 13.4 mm on optical coherence tomography (OCT) (Fig. 1a, the lower panels). Angiogram also demonstrated a 4.0 × 16 mm CS (GRAFTMASTER, Abbott Vascular) would jail at least one RVB (Fig. 1b, the upper left panel, a white dotted line). Accordingly, implantation with high pressure (20 atm) and post-dilatation with a 5.0-mm non-compliant balloon (22 atm) was performed to cause intentional shortening of the CS, the degree of which was reported to be potentially approximately 3 mm using larger balloons [1]. Consequently, CAA was excluded with preserved flow into both RVBs (Fig. 1b, the upper right panel) and the implanted CS was shortened by 3.0 mm on OCT (proximally 1.4 mm and distally 1.6 mm in length, Fig. 1b, the lower panels). The edge injury related to the CS implantation with high pressure was successfully avoided, thanks to the first stent, the length of which was longer than that of the CS, as a previous report suggested [2]. At the 10-month follow-up, he had been symptom free. The patency of both RVBs, absence of CAA, and shortened CS without restenosis were also confirmed by coronary computed tomography. In ex vivo testing, the reproducibility of CS-shortening was confirmed as well. A 4.0 × 16 mm GRAFTMASTER became shortened to 13.4 mm following same procedure performed in the present case (Online Figure). Although it would be difficult to predict the degree of CS-shortening in length and direction accurately, CS-shortening occurred almost equally between proximal and distal segments in the bench test as well. Herein, we report intentional shortening of CS skirt by high-pressure expansion with a large balloon as a promising therapeutic option to exclude CAA percutaneously without compromising side-branches.