Comparison of RA-IVL and RA-SHP in Calcified Coronary Lesions

Severely calcified coronary lesions reduce vessel compliance, limit balloon expansion, and impair optimal stent deployment, leading to higher procedural risk. Rotational atherectomy (Rota) can modify superficial calcium but may be insufficient for deep or circumferential calcium. Intravascular lithotripsy (IVL) and super high-pressure balloon angioplasty (SHPB) are both used for additional calcium modification, but direct comparative evidence in the "post-Rota lesion optimization" setting is limited.

This multicenter, prospective, randomized, single-blind trial compares Rota + IVL versus Rota + SHPB for imaging-defined lesion optimization and periprocedural safety in severely calcified de novo coronary lesions, with clinical follow-up through 12 months.

Study design and sites

• Design: Prospective, multicenter, randomized controlled, single-blind trial; 1:1 allocation.
• Sites: Beijing Chaoyang Hospital, Capital Medical University (coordinating center); China-Japan Friendship Hospital; Xinhua Hospital, Shanghai Jiao Tong University School of Medicine.
• Study period: January 2026 to December 2028.
• Sample size: 162 participants (81 per group).
• Blinding: Operators are not blinded. Imaging analysts and/or (if applicable) endpoint adjudicators are blinded to treatment allocation.

Core workflow (screening to final imaging)

1. Screening and baseline assessment

• Collect clinical data, angiography, and planned OCT/IVUS when applicable.
• Peri-procedural medications are administered per guideline-based and institutional practice and documented (antiplatelet therapy, intraprocedural anticoagulation, etc.).

1. Initial rotational atherectomy (all participants)

• Rota is performed using a standardized approach across sites.
• Maximum burr size: ≤1.5 mm.
• Key procedural parameters are recorded (burr size, rotational speed, runs, and any complications and treatments).

1. Post-Rota "randomization trigger" assessment

• OCT/IVUS and/or a protocol-defined balloon test is used to determine whether additional lesion optimization is needed (e.g., residual calcific constraint/inadequate compliance).
• Eligible participants meeting trigger criteria are randomized 1:1 to IVL or SHPB.
• Stratification factors: study site; reference vessel diameter (2.5-3.0 mm vs >3.0-4.0 mm).

1. Randomized lesion optimization and stent implantation Rota + IVL arm

• An appropriately sized IVL balloon is advanced across the lesion.
• Lithotripsy is delivered per protocol limits (up to 80 pulses/8 cycles).
• Repeat treatment and/or balloon resizing under imaging guidance is allowed and fully documented. Rota + SHPB arm
• SHPB dilation is performed to modify the lesion.
• Target pressure: ≥30 atm (pressure escalation steps, inflation duration, and maximum pressure per protocol; all parameters documented).
• Repeat inflations and/or balloon exchange are allowed and documented. After randomized optimization, stent implantation and post-dilation are performed under imaging guidance. Devices and parameters are recorded (stent and post-dilation balloon sizes, pressures, number of inflations).

1. Immediate post-procedure imaging assessment (endpoint measurements)

• OCT/IVUS is performed after stent implantation and final post-dilation.
• Imaging pullbacks must cover the lesion and proximal/distal reference segments and meet minimum quality criteria.
• Quantitative analysis follows prespecified definitions (e.g., post-procedural MLD, minimal stent area, stent expansion and apposition metrics).
• Calcium morphology (arc, length, thickness, distribution) is captured for exploratory correlation and subgroup analyses.

Safety monitoring and quality control

• Periprocedural complications (e.g., perforation, dissection, slow-/no-reflow, acute stent thrombosis) are captured, graded, and reported using prespecified definitions and timelines.
• Data are collected using standardized CRFs and a multicenter database for data capture, follow-up tracking, and quality assurance.
• Monitoring focuses on: eligibility, randomization trigger criteria, key imaging timepoints, major safety events, and follow-up completeness.

Follow-up

• In-hospital monitoring until discharge.
• Clinical follow-up at 30 days, 6 months, and 12 months (clinic visit and/or telephone).
• Collection of clinical events, bleeding and renal outcomes, and resource utilization metrics (procedure time, contrast volume, radiation exposure).
• Imaging follow-up (if specified in the protocol or clinically indicated) may be performed selectively at designated centers.

Statistical considerations (overview)

• A noninferiority framework is used to compare the primary imaging outcome between groups.
• Primary analysis population: intention-to-treat (ITT), with supportive per-protocol (PP) analysis.
• Stratification factors are incorporated in the analysis model. Missing imaging data are handled using prespecified methods with sensitivity analyses.