Long-term clinical outcomes after rotational vs. orbital atherectomy for calcified lesions: insights from the DIRO trial

Backgrounds Calcified lesions limit stent expansion and are associated with poor clinical outcomes. Atherectomy devices, including rotational atherectomy (RA) and orbital atherectomy (OA), can reduce calcium volume and potentially improve clinical outcomes. We previously conducted the DIRO trial, a prospective randomized study comparing RA (n=50) vs OA (n=50) for calcified lesions using optical coherence tomography (OCT) guidance. The trial showed that RA achieved greater tissue modification and stent expansion than OA. However, 8-month clinical outcomes did not differ between the 2 groups. The long-term clinical impact of these devices remains unclear. Purpose This study aimed to evaluate the long-term clinical outcomes of RA and OA followed by drug-eluting stents implantation. Methods In the DIRO trial population, the long-term incidence of target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, and target lesion revascularization (TLR), was assessed and compared between RA and OA groups using a log-rank test. Results Figure 1 presents patient demographics, lesion and procedural characteristics, and OCT findings. Stent expansion was significantly larger in the RA group than in the OA group. The medium follow-up period was 1095 days. The 3-year TLF rate was 13% in RA group vs 11% in OA group. Figure 2 shows Kaplan-Meier curves of TLF and its individual components. Conclusions Long-term TLF rate was low following adequate atherectomy under OCT guidance and was comparable between the 2 groups.