Relationship between angiographic late loss and target lesion revascularization after coronary stent implantation: Analysis from the TAXUS-IV trial

Abstract

We sought to evaluate the relationship between angiographic late loss and clinical outcomes in the drug-eluting stent era. The interrelationship between angiographic late loss, binary restenosis, and clinical recurrence (target lesion revascularization [TLR]) after coronary stent implantation has been incompletely evaluated. Using the angiographic substudy of the TAXUS-IV trial, in which 1,314 patients with de novo coronary lesions were randomized to either the paclitaxel-eluting TAXUS stent or to its bare-metal equivalent, we defined the relationship between in-stent and analysis segment late loss, the shape of the late loss histogram (variance and skewedness), and nine-month TLR. Late loss by several measures was closely related to TLR (area under the receiver-operator curve >0.90). For individual vessels of the size in this study (2.8 +/- 0.5 mm), the likelihood of TLR did not exceed 5% until analysis segment late loss was >0.5 mm, and did not exceed 10% until late loss was >0.65 mm. At greater late losses, the late loss TLR relationship was steep and nearly linear. For the overall patient cohort, the rate of TLR was related, however, not only to median late loss, but also to measures of its statistical distribution (TLR increased with lack of homogeneous biologic response [greater variance and greater right skewedness]). Similar relationships held for late loss measured within the confines of the stent itself. Coronary stents result in large lumens with "room" to accommodate up to approximately 0.5 to 0.65 mm of tissue (angiographic analysis segment late loss) before the likelihood of clinical restenosis (TLR) exceeds 5% to 10%. These data have important implications toward understanding the absolute and relative efficacy of drug-eluting stents.