Excimer Laser Atherectomy in the Management of Undilatable Coronary Stents

Abstract

Introduction: Excimer laser has been reported to be safe and effective in the management of undilatable stents. We report our initial experience. Methods: From March 2016 to January 2019, 10 patients (ages 62-84, 9 male) were treated for constrained stents despite high-pressure balloon inflation (>26 atmospheres). Indications were threatened stent-thrombosis in 1 and recurrent restenosis (>3) with refractory symptoms in 9. All patients had clear angiographic evidence of a poorly expanded stent showing > 30% stent constraint, and 7 patients had multiple layers of stent. The procedure was performed under GA via 7F guiding catheter with a 0.9mm 80mJ/mm2/80Hz catheter (Spectranetics). Tissue debulking with a bloodless field was first performed followed by multiple contrast runs (average 6, 4-12). Lesions were post-dilated at >20 atmospheres and then treated with DEB. Target vessels included RCA (5), LAD (2), LCx (1), Intermediate (1), and SVG-to-1MCx (1). Results: Complete angiographic success (full stent-expansion, zero residual stenosis) occurred in 6 patients and partial-success (stent-constraint <15%, <30% residual stenosis) in 4. Multiple layers of stent were associated with partial-success. Micro-bubbles, slow-flow and pronounced ST-elevation occurred transiently in all patients. None required re-stenting. There were no procedural complications, all vessels had TIMI-3-flow and isoelectric ECGs on completion. Average next-day high-sensitivity-troponin-T level was 420ng/L. At 30-days and 1-year follow-up, there have been no deaths, and only one patient required TVR downstream in an untreated area 3 months later. Conclusion: Excimer laser represents a therapeutic option for the management of a small group of highly selected and symptomatic patients.