Analysis of left main coronary artery bifurcation lesions treated with biolimus-eluting DEVAX AXXESS plus nitinol self-expanding stent: intravascular ultrasound results of the AXXENT trial.

Objective: To assess the efficacy of the AXXESS stent on the treatment of left main coronary artery (LMCA) bifurcation lesions using IVUS. Background: The treatment of LMCA bifurcation lesions remains challenging even with the use of drug-eluting stents. The AXXESS system is a biolimus A9-eluting self-expanding stent, dedicated to the treatment of bifurcation lesions. Methods: Data were obtained from the AXXENT trial, a prospective, single-arm, multicenter study designed to evaluate the efficacy of the AXXESS stent on the treatment of LMCA bifurcation lesions. IVUS was available in 26 cases at 6-months follow-up. Volumetric and cross-sectional analyses within the AXXESS stent, and cross-sectional analyses at the ostia of left anterior descending (LAD) and left circumflex coronary arteries (LCX) were performed. Results: Within the AXXESS stent, percent neointimal volume obstruction was (3.0 +/- 4.1)% with a minimal lumen area of 10.3 +/- 2.6 mm(2). AXXESS stent volume showed an 12.4% increase at follow-up compared with postprocedure (P = 0.04). Lumen area was significantly smaller in the LCX ostium compared with the LAD ostium at follow-up (3.6 +/- 1.3 mm(2) vs. 5.5 +/- 2.0 mm(2), p = 0.0112). There was greater neointimal formation in the LCX ostium compared with the LAD ostium (1.37 +/- 1.20 mm(2) VS. 0.30 +/- 0.36 mm(2), p = 0.0003). Conclusions: The AXXESS stent in the LMCA showed enlargement through 6-months follow-up and significant neointimal suppression. Greater neointimal formation and relatively inadequate stent expansion may contribute to luminal narrowing in the LCX ostium. (C) 2008 Wiley-Liss, Inc.