Outcomes of stenting extra-small (≤2.25 mm) vessels using the Resolute zotarolimus-eluting stent (R-ZES)

AIMS: We assessed long-term outcomes in patients with extra-small (XS) (≤2.25 mm) and small vessels (SV) (>2.25-2.75 mm) treated with the Resolute zotarolimus-eluting stent (R-ZES). METHODS AND RESULTS: Data from eight studies including patients with XS or SV were pooled for this analysis. Among 2,141 patients (837 XS, 1,304 SV), three-year cumulative major adverse cardiac events (15.4% vs. 11.5%; adj. HR [95% CI]: 1.3 [1.0, 1.7], p=0.12), target lesion failure (12.4% vs. 9.3%, adj. HR: 1.1 [0.8, 1.5], p=0.56), and target lesion revascularisation (TLR: 6.9% vs. 4.5%, adj. HR 1.4 [0.9, 2.1], p=0.17) were greater in the XS cohort but were not significantly different after propensity adjustment. Target vessel revascularisation occurred more frequently in XS patients in both unadjusted and adjusted analyses (11.2% vs. 7.6%, adj. HR: 1.5 [1.1, 2.1], p=0.02). Stent thrombosis was low in both cohorts (1.2% vs. 0.6%, p=0.09). In the XS cohort, insulin-dependent diabetics had over twofold higher rates of TLR than non-diabetics (13.6% vs. 6.0%, p=0.02). CONCLUSIONS: Long-term lesion-specific results among patients with XS vessels treated with the R-ZES were not significantly different from those among patients with SV, but specific patients with XS vessels (e.g., insulin-dependent diabetics) may remain at high risk for TLR.