Abstract 12989: Generalizability of Quantitative Angiographic In-Segment Late Lumen Loss Imaging in Eastern and Western Populations: Can We Facilitate Global Drug Eluting Stent Evaluation?
Background: Regulators require mechanistic observations of late lumen loss (LLL) in evaluating new drug eluting stents (DES). Redundant requirements for follow-up catheterization across regulatory jurisdictions worldwide could be reduced if independent core laboratory quantitative coronary angiography (QCA) findings were generalizable. Our study aim was to assess comparability of QCA LLL in East (Japan, China) and West (N. America, Europe) pts using the world’s largest compilation of late follow-up QCA data.
Hypothesis: The propensity adjusted mean difference in QCA in-segment LLL between East and West is ≤0.4mm, with 95% confidence.
Methods: All available data from 4 manufacturers (7157 pts, 29 trials) reporting 6-12mo QCA LLL were compiled. East vs West were compared unadjusted and via propensity score (PS) quartiles that adjusted for 26 clinical descriptive and anatomic variables affecting QCA LLL. Of the 7157 pts, 6163 (86%) had complete covariable profiles and comprised the analysis set. Based on consensus of experts and regulators, a clinically meaningful difference between East and West mean IS-LLL was prospectively set at 0.4mm.
Results: Of 6163 pts, 4134 were West and 2029 East, including 2304 paclitaxel, 1455 everolimus, 1562 zotarolimus, 440 sirolimus and 402 biolimus exposures. Unadjusted and adjusted IS-LLL (Mean±SD) was 0.25±0.47 (W) and 0.08±0.41 (E), and 0.24±0.45 (W) and 0.13±0.45 (E), respectively; differences (95% CI) were 0.17 (0.15, 0.19) and 0.12 (0.08, 0.16), respectively. PS-adjusted IS-LLL is shown the Figure. All differences were ≤ 0.4mm.
Conclusion: In the world’s largest compilation of protocol follow-up across multiple DES platforms, QCA LLL appears generalizable and sufficiently predictive across East and West pts in both unadjusted and adjusted comparisons. This suggests that global DES evaluations can be facilitated by reducing the need for redundant invasive late catheterization across regulatory jurisdictions.
Author Disclosures: V. Radhakrishnan: None. J.C. Allen: None. R. Fisher: None. W. Lye: None. R.W. Harrison: None. M.W. Krucoff: None.
- © 2014 by American Heart Association, Inc.