Propensity and mechanisms of restenosis in different coronary stent designs - Complementary value of the analysis of the luminal gain-loss relationship

OBJECTIVES This study sought to investigate the influence of stent design o n the long-term angiographic outcome. BACKGROUND The proportional relationship betrveen vessel injury and late lu minal toss in pcrcutaneous revascularization should be best appreciated in coronary stenting, where recoil and shrinkage are theoretically minimal. It is unclear whether all stent designs can counterbalance this reactive loss by achieving a large initial luminal gain (bigger is better). METHODS In 523 lesions successfully stented, the long-term angiographic res ults of slotted-tube (n = 331), coil (n = 85), multicellular (n = 70) and s elf-expandable mesh (n = 37) stent designs were compared using the angiogra phic gain-loss relationship (GLR). RESULTS Restenosis rate was 10%, for multicellular, 20% for slotted-tube, 4 6% for coil and 49% for self-expandable designs (p = 0.001). At a differenc e with other designs, no significant GLR was found in coil stents, suggesti ng additional mechanisms of luminal loss (i.e., plaque protrusion, stent co mpression) to neointimal proliferation. Significant differences in late los s between stents were found within each quartile of luminal gain, suggestin g a specific role of design in luminal loss. Multivariate analysis identifi ed use of coil and self-expandable stents, vessel size, minimal luminal dia meter preintervention, luminal gain and scent length as variables with inde pendent predictive value for several indices of angiographic long-term outc ome. CONCLUSIONS The analysis of GLR: 1) demonstrates that stent design influenc es late luminal loss; 2) challenges the applicability of the widely accepte d "bigger is better" approach to all stent designs; and 3) appears as a val uable tool in assessing long-term stent performance. (C) 1999 by the Americ an College of Cardiology.