Serial intravascular ultrasound analysis of complex bifurcation coronary lesions treated with the Tryton Bifurcation Stent in conjunction with an everolimus-eluting stent: IUVANT (Intravascular Ultrasound Evaluation of Tryton Stent) study.

Abstract

To characterize the treatment of complex bifurcation lesions (BL) with the Tryton Bifurcation Stent (TBS) paired with an everolimus-eluting stent (EES). Complex BL are associated with higher procedural complications and poorer long-term outcomes. The TBS is a dedicated side-branch (SB) stent designed to be used in conjunction with a standard drug-eluting stent. Prospectively identified, consecutive patients underwent TBS+EES stenting of BL using a protocol which included TBS postdilation and simultaneous final kissing balloon inflations (FKBI). All lesions were systematically evaluated with coronary angiography and IVUS, obtained at procedure completion and at 9 months, and were assessed by independent core laboratories. Thirty-three BL were treated in 32 patients presenting primarily (87.5%) with stable angina and complex BL with angiographic apparent disease in the main vessel (MV) and SB in 87.9% and 75% by site and core evaluation, respectively. Procedural success was 100% and high postprocedure percent stent expansion (MV 96 [93, 109]%, SB 88 [77, 100]%, carina MV 135 [99, 166]%, carina SB 116 [91, 130]%) was demonstrated by IVUS. At 9-month angiographic follow-up (n = 28 patients), one MV in-segment restenosis and one SB in-stent restenosis were observed. SB in-stent late lumen loss was 0.41 ± 0.27 mm. IVUS assessment revealed the absence of stent recoil; percent carinal neointimal hyperplasia (NIH) was 1.8 [0.0,11.2]% in MV and 15.0 [6.7,23.5]% in SB, with NIH volume obstruction of 2.0 [0.7,4.3]% in MV and 14.2 [7.5,29.6]% in SB. Stenting of complex BL with the TBS+EES provides high acute success with sustained clinical, angiographic, and IVUS results at 9 months. These excellent results are likely due to the extent of stent expansion at the carina.