Late loss in lumen diameter and binary restenosis for drug-eluting stent comparison.
BACKGROUND
Published rates of coronary restenosis have fallen below 10% in drug-eluting stent trials. Early evaluations of new stents have used continuous end points that are presumed surrogates for restenosis, but the generalizability and power of such end points have not been examined systematically.


RESULTS
We examined the relationship between incremental changes in observed late loss in lumen diameter and the probability of restenosis using reported late loss from 22 published trials of various types of stents (bare-metal, drug-eluting, and small-vessel stents). Next, the power of late loss differences was compared with that of corresponding binary restenosis rates. The relationship between mean late loss and its SD was linear and did not vary with stent type (drug-eluting or bare-metal) or vessel diameter. At all levels of late loss examined (0 to 1 mm), incremental changes were associated with increasing restenosis risk (with an increasing magnitude of effect at higher levels of late loss). The power to detect a treatment effect was greater for late loss than for binary angiographic restenosis (> or =32% relative increase in power, > or =24% absolute increase for late loss between 0.2 and 0.6 mm).


CONCLUSIONS
Late loss is monotonically related to restenosis risk in published stent trials. It is a generalizable and powerful angiographic end point in early or small trials of new drug-eluting stents.
Mauri
Laura
L
Brigham and Women's Hospital and Harvard Medical School, Boston, Mass 02116, USA. lmauri1@partners.org
Orav
E John
EJ
Kuntz
Richard E
RE
D002986:Clinical Trials as Topic / Q000706:statistics & numerical data; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000175:diagnosis* / Q000473:pathology; D003331:Coronary Vessels / Q000473:pathology*; D006801:Humans; D016239:MEDLINE; D004364:Pharmaceutical Preparations / Q000008:administration & dosage; D011237:Predictive Value of Tests; D011336:Probability; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D013997:Time Factors; D016896:Treatment Outcome
D004364:Pharmaceutical Preparations