Performance of everolimus-eluting versus paclitaxel-eluting coronary stents in small vessels: results from the SPIRIT III and SPIRIT IV clinical trials.

BACKGROUND

Higher rates of adverse cardiac events have been observed in patients with small vessel disease. Therefore, we compared an everolimus-eluting stent (EES) to a paclitaxel-eluting stent (PES) for treatment of small (reference vessel diameter: RVD <2.5 mm) and larger vessels (≥2.5 mm) in a pooled analysis from the SPIRIT III (n = 1,002) and SPIRIT IV (n = 3,687) trials (randomized 2:1, EES vs. PES).

METHODS

Data of 4,689 total patients were pooled for a patient level analysis. Lesion length, RVD, and percent diabetics were matched between stent types. EES versus PES performance was evaluated at 1 year in patients with small (n = 1,019) and larger vessels (n = 2,586) who had a single lesion treated.

RESULTS

Mean RVD assessed by quantitative coronary angiography in patients with small vessels was 2.24 ± 0.19 and 2.25 ± 0.20 mm in the EES and PES groups, respectively. At 1 year, EES compared to PES in small vessel patients significantly reduced major adverse cardiac events (4.5% vs. 7.9%, P = 0.04), target lesion failure (4.4% vs. 7.9%, P = 0.03), target lesion revascularization (2.4% vs. 5.5%, P = 0.02), and stent thrombosis (0.2% vs. 1.2%, P = 0.04). Relative benefits of EES versus PES were comparable in small and larger vessels (P interaction > 0.05), although the absolute benefits were greater in patients with small vessel disease.

CONCLUSION

In high-risk patients requiring percutaneous coronary intervention in small coronary arteries, EES results in significantly improved 1-year rates of event-free survival compared to PES, with evidence present for both enhanced safety and efficacy.