Enhanced Efficacy of Rotational Atherectomy for Calcified Nodules With Contralateral Calcification: Insights From a Multicenter Intravascular Ultrasound Imaging Study

BACKGROUND: Calcified nodules (CNs) represent a high-risk coronary lesion phenotype associated with target lesion revascularization (TLR). Although rotational atherectomy (RA) is an established treatment for calcified lesions, its benefit for CNs remains unclear. This study aimed to evaluate the impact of RA on TLR and to identify specific morphological features on intravascular ultrasound that may influence its therapeutic effect for CNs. METHODS: In a substudy of the U-SCAN registry (Coronary Intravascular Ultrasound for Calcified Nodule), 348 patients with CNs identified by intravascular ultrasound who underwent percutaneous coronary intervention were analyzed. We excluded patients with in-stent restenosis, use of alternative debulking devices, failed device passage without RA, and poor image quality. The final analysis included 209 patients, stratified by RA use. Multivariable Cox proportional hazards models were used to identify predictors of TLR and assess treatment interactions across subgroups. RESULTS: Among 209 patients, 79 patients (37.8%) underwent RA. During a median follow-up of 2.1 years (interquartile range, 0.4–4.9), TLR was required in 20 of 79 patients (25.3%) in the RA group and 41 of 130 patients (31.5%) in the non-RA group. After adjustment, RA independently predicted reduced TLR (hazard ratio, 0.34 95% CI, 0.19–0.62, P <0.001). In addition, intravascular ultrasound–derived calcification features, including greater lumen area stenosis, longer CN length, smaller final minimum lumen area, and adjacent circumferential calcification, were significantly associated with TLR. Notably, the benefit of RA on TLR was pronounced in patients with contralateral calcification (8.6% versus 51.6%, P <0.001). In contrast, without this feature, the TLR rate was higher in the RA group (38.6% versus 25.3%, P =0.11), resulting in a statistically significant interaction ( P interaction <0.001). CONCLUSIONS: In patients with CNs, RA was associated with a reduced long-term risk of TLR. The presence of contralateral calcification identifies a subgroup deriving substantial benefit, supporting a more selective, morphology-guided approach to treatment. REGISTRATION: URL: https://jrct.mhlw.go.jp/ ; Unique identifier: jRCT1050240037.