Randomized comparison of clinical outcomes between intravascular ultrasound and angiography-guided drug-eluting stent implantation for long coronary artery stenoses

Objectives: This study sought to assess the impact of intravascular ultrasound (IVUS) guidance on clinical outcomes following drug-eluting stent implantation when treating long lesions. Background: The role of IVUS guidance when treating long lesions has been tested during bare-metal stent, but not during drug-eluting stent, implantation. Methods: A total of 543 patients treated with stents ≥28 mm in length were randomly assigned to IVUS guidance (n = 269) versus angiography guidance (n = 274). The primary endpoint was a composite of major adverse cardiac events (MACE), including cardiovascular death, myocardial infarction, target vessel revascularization, or stent thrombosis at 1 year following intervention. Results: In the intention-to-treat analysis, total stent length was 32.4 mm in the IVUS-guided arm versus 32.3 mm in angiography-guided arm (p = 0.84). Adjunct post-dilation was more frequently performed in the IVUS-guided arm (54.6% vs. 44.5%, p = 0.03); post-intervention minimal lumen diameters were similar (2.55 vs. 2.55 mm, respectively, p = 0.50); and MACE occurred in 12 (4.5%) patients in IVUS-guided arm and in 20 (7.3%) patients in the angiography-guided arm (p = 0.16). However, among the 269 patients assigned to IVUS guidance, IVUS was not used in 13 patients (4.8%); conversely, in 274 patients assigned to angiography alone, 41 patients (15.0%) were treated with IVUS guidance. Therefore, in a per-protocol analysis according to actual IVUS usage, minimum lumen diameter was larger (2.58 vs. 2.51 mm, p = 0.04), and MACE rates were lower: 4.0% in the IVUS-guided arm versus 8.1% in the angiography-guided arm (p = 0.048). Conclusions: A strategy of routine IVUS for drug-eluting stent implantation in long lesions did not improve the 1-year MACE rates. The IVUS use per operator decision was associated with improved results.