792-2.Is the Anti-Restenosis Effect of Stent (vs PTCA) Greater in LAD Vessels? A Subgroup Analysis of the STent REStenosis Study

Abstract

In the multicenter randomized STent REStenosis Study (STRESS), stent (S) implantation has shown to reduce restenosis (RES) by 26% compared with PTCA. To determine the impact of Svs PTCA in reducing RES in various vessel locations, we analyzed the data from STRESS in LAD and non-LAD vessels. LAD PTCA N = 98 LAD S N = 96 Non-LAD PTCA N = 104 Non-LAD S N = 109 Final % stenosis 34 ± 15 17 ± 11 † 35 ± 14 20 ± 12 † Acute gain (mm) 1.14 ± 0.47 1.62 ± 0.43 † 1.32 ± 0.49 1.81 ± 0.47 † Late Loss (mm) 0.52 ± 0.55 0.78 ± 0.57 * 0.34 ± 0.57 0.73 ± 0.57 † Net gain (mm) 0.59 ± 0.55 0.88 ± 0.62 * 1.03 ± 0.61 1.06 ± 0.61 RES (>50% stenosIs) 52.6 32.9 * 29.9 29.5 * . p ≤ 0.01 † . p ≤ 0.0001 compared S with PTCA In both LAD and non-LAD vessels, S (compared with PTCA) achieved a greater acute ga in and resulted in a lower final % stenosis. Late loss was also greater in S than PTCA group and similar for LAD and non-LAD vessels. However, in PTCA pts, late loss was much lower in non-LAD vessels (vs LAD). Thus, the overall net gain and RES in non-LAD vessels were similar for S.and PTCA, whereas the net gain was greater after S in LAD vessels and resulted in much lower RES compared with PTCA. Similarly, the difference in eventfree survival (freedom from death, MI, CABG, or repeat PTCA) between S and PTCA was greater in LAD (77% vs 66%, P = 0.06) than non-LAD vessels (78% vs 72%, NS). STRESS substudy analysis indicates 1) S provides uniformly greater improvement of angiographic results in all lesion locations compared with PTCA, 2) much greater anti-restenosis and clinical benefits in S pts within the LAD vessels, and 3) more aggressive post-S dilatation strategies (to further reduce final % stenosis) are recommended for non-LAD vessels to achieve greater differential anti-restenosis benefit for S.