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Evaluation of Calcified Coronary Lesion Preparation With the Naviscore Scoring Balloon

MILOU: Minimize Intra Luminal Obstructive Underexpansion: A Prospective, Multi-Center Randomized Trial for the Evaluation of Calcified Coronary Lesion Preparation With the Naviscore Scoring Balloon

Status
Not yet recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07650578
Acronym
MILOU
Enrollment
200
Registered
2026-06-16
Start date
2026-07-01
Completion date
2028-06-01
Last updated
2026-06-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Calcific Coronary Arteriosclerosis, Coronary Arterial Disease (CAD)

Keywords

Percutaneous Coronary Intervention, Lesion Preparation, Scoring Balloon, Intravascular Ultrasound, Stent Expansion, Coronary Artery Calcification

Brief summary

The purpose of this clinical study is to evaluate the effectiveness and safety of a specialized medical device, the Naviscore scoring balloon, in preparing calcified coronary artery narrowings before the implantation of a drug-eluting stent. During percutaneous coronary interventions, the presence of calcified plaques in the heart arteries represents a major challenge because it can prevent stents from expanding fully. When a stent remains under-expanded, it significantly increases the long-term risk of arterial re-narrowing or blood clot formation. To optimize stent expansion, appropriate preparation of the diseased vessel section before stent insertion is a critical phase. This study is a prospective, multi-center randomized trial designed to test the hypothesis that treating calcified coronary lesions with the Naviscore scoring balloon will achieve a better stent expansion and a larger final minimal stent area compared to standard lesion preparation using regular non-compliant balloons. Eligible participants will be randomized in a one-to-one ratio to one of these two lesion preparation strategies. For all included patients, standard drug-eluting stents will be deployed. The study will use intravascular ultrasound imaging to evaluate the final minimum area of the stent directly inside the treated artery at the site of the highest initial calcium burden. Participant health and clinical outcomes will be monitored for up to twelve months following the procedure.

Detailed description

Percutaneous transluminal coronary angioplasty (PTCA) is the main technique in percutaneous coronary intervention (PCI). It aims to restore coronary blood flow by mechanically enlarging a stenotic arterial segment through controlled balloon inflation within the vessel lumen. The acute luminal gain with balloon angioplasty is the result of multiple mechanisms, ranging from percolation and longitudinal redistribution of atheroma, to plaque fracture, and overstretching of the vessel wall, often accompanied by intimal tearing and medial dissection. While contemporary drug-eluting technologies have significantly improved long-term clinical outcomes, fibrocalcified atheromatous intracoronary plaques still present a significant challenge for stent crossing and optimal deployment. Research has demonstrated that suboptimal stent expansion and malapposition are significant contributing factors to restenosis and stent thrombosis rates, regardless of the type of stent used. Intravascular imaging registries have identified that twenty to thirty percent of deployed stents remain under-expanded or malapposed in daily clinical practice. Severe coronary calcification can make it difficult to deliver devices and can limit the expansion of stents, which can result in suboptimal improvement in blood flow and an increased risk of adverse events, including target lesion failure. Furthermore, heavily calcified lesions have been found to be associated with higher rates of vessel dissection, perforation and impaired anti-proliferative drug delivery, resulting from the mechanical barrier of the calcium burden. In order to achieve successful stent deployment, optimal preparation of fibro-calcific lesions is essential and involves a number of plaque modification strategies. Focused force angioplasty is a procedure that targets specific locations of the plaque, focusing inflation forces on the area to induce localized stress and facilitate cracking. It is crucial to ensure that the pre-dilatation balloon is correctly sized to maximise safety by minimising the risk of advanced coronary perforation or severe medial damage. It is imperative that sizing compliance chart data is followed rigorously, as compliant balloons can display an unpredictable non-linear expansion behaviour at higher pressures, whereas non-compliant balloons maintain a stable volume, concentrating their dilating force directly at the calcified site up to their rated burst pressure. Semi-compliant pre-dilatation balloons often expand asymmetrically in resistant lesions, increasing the risk of edge dissections. The sizing and performance of scoring devices and non-compliant balloons remains limited in contemporary clinical literature. This randomised trial is designed to evaluate the post-market clinical performance, safety and comparative effectiveness of the Naviscore scoring balloon catheter manufactured by iVascular.

Interventions

DEVICEScoring Balloon PTCA Catheter

Percutaneous coronary preparation of calcified coronary stenosis using the rapid exchange Naviscore scoring balloon catheter before drug-eluting stent deployment. The device incorporates an over-the-balloon metallic nitinol element designed to focally concentrate dilation forces, minimizing balloon slippage and scoring the atheromatous plaque at lower pressures to facilitate optimal stent expansion. Sizing is based on a 0.8:1 to 1:1 ratio relative to the reference lumen. Operators must execute a specific sequence of inflating the scoring balloon to nominal pressure, fully deflating it, mobilizing it within the lesion, and reinflating it, repeated three to four times across the target segment to ensure multi-focal plaque disruption before stenting.

DEVICENon-Compliant (NC) Angioplasty Balloon

Conventional non-compliant (NC) PTCA balloon catheter used for standard lesion pre-dilatation according to routine clinical practice, inflated below the rated burst pressure without parallel guidewires in place.

Sponsors

University of Mons
Lead SponsorOTHER
iVascular S.L.U.
CollaboratorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Patient written consent is given, ≥18 years. * A de novo lesion to be treated in a vessel between 2.5 and 4.0 mm. * Moderate to heavily calcified lesions detected by coronary angiography on two orthogonal views, and confirmed by IVUS if the lesion can be crossed with the catheter.

Exclusion criteria

* Patient \<18 years old. * Pregnant female. * Contraindication to dual antiplatelet therapy. * Thrombocytopenia (under 100 000). * Major surgical intervention planned within one year. * Significant left main lesion. * Chronic total occlusion. * Lesion in a graft. * In-stent restenosis lesion. * Lesion responsible of a ST elevated Myocardial Infarction (STEMI)

Design outcomes

Primary

MeasureTime frameDescription
Final Minimal Stent Area (MSA)Immediately post-stenting optimization during the index percutaneous coronary intervention (PCI) procedure.The minimal stent area (MSA) will be measured in square millimeters by intravascular ultrasound (IVUS) after final procedural optimization. The primary comparison will evaluate the MSA specifically at the exact site of the initial heaviest calcium burden to demonstrate the superiority of the Naviscore scoring balloon over standard non-compliant (NC) balloons.

Secondary

MeasureTime frameDescription
Minimal Stent Area (MSA) Across the Entire Stented SegmentImmediately post-stenting optimization during the index percutaneous coronary intervention (PCI) procedureThe minimal stent area (MSA) in square millimeters measured across the entire length of the deployed segment using intravascular ultrasound (IVUS) pullbacks to evaluate overall stent expansion expansion
Stent Eccentricity at the Site of the Minimal Stent AreaImmediately post-stenting optimization during the index percutaneous coronary intervention (PCI) procedureStent eccentricity index calculated as the ratio of the minimum stent diameter over the maximum stent diameter, measured via intravascular ultrasound (IVUS) at the exact cross-section of the minimal stent area segment
Stent Eccentricity at the Initial Heaviest Calcium Burden SiteImmediately post-stenting optimization during the index percutaneous coronary intervention (PCI) procedureStent eccentricity index calculated as the ratio of the minimum stent diameter over the maximum stent diameter, measured via intravascular ultrasound (IVUS) specifically at the cross-section matching the initial heaviest baseline calcium plaque burden
Device Success RateDuring the index percutaneous coronary intervention (PCI) procedurePercentage of cases achieving successful delivery of the assigned pre-dilatation balloon, complete inflation with adequate lesion preparation, and the absolute absence of vessel rupture or advanced coronary perforation categorized by the Ellis classification
Major Adverse Cardiac Events (MACE) RateAt 1 and 12 months post-procedurePercentage of participants experiencing Major Adverse Cardiac Events (MACE), defined as a composite clinical endpoint of myocardial infarction, stroke or transient ischemic attack, or cardiac death
Target Lesion Failure (TLF)At 1 and 12 months post-procedurePercentage of participants experiencing Target Lesion Failure (TLF), defined as a composite of cardiac death, target-vessel myocardial infarction defined according to ARC-2 criteria, or clinically indicated Target Lesion Revascularization
Target Vessel Failure (TVF)At 1 and 12 months post-procedureDefined as a composite of cardiac death, target-vessel myocardial infarction, or clinically indicated Target Vessel Revascularization (TVR).
Clinically Indicated Target Lesion Revascularization (TLR)At 1 and 12 months post-procedurePercentage of participants requiring a repeat percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG) driven by a recurrent narrowing inside the originally treated target lesion segment (including the stent and its five-millimeter proximal and distal borders), which is accompanied by clinical symptoms of ischemia or objective functional evidence of myocardial ischemia.
Clinically Indicated Target Vessel Revascularization (TVR)At 1 and 12 months post-procedurePercentage of participants requiring any repeat percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG) in any segment of the originally treated target vessel, driven by angiographic restenosis or disease progression, and accompanied by clinical symptoms of ischemia or objective functional evidence of myocardial ischemia.
Procedural Success RateDuring the index percutaneous coronary intervention (PCI) procedure and until hospital discharge (up to 24 hours post-procedure).Percentage of cases achieving Device Success (successful delivery of the assigned balloon and complete inflation with adequate lesion preparation) combined with a final residual stenosis of less than thirty percent as measured by quantitative coronary angiography (QCA) and a final Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow, without the occurrence of in-hospital Major Adverse Cardiac Events (MACE).
Final Residual Stent UnderexpansionAt the end of the index percutaneous coronary intervention (PCI) procedure (immediate post-stenting optimization).Evaluation of the final residual underexpansion of the drug-eluting stent after deployment and high-pressure post-dilatation, measured in millimeters using motion-corrected X-ray stent visualization software (StentBoost or equivalent stent enhancement method) in two orthogonal views without contrast.
Final Stent Diameter StenosisAt the end of the index percutaneous coronary intervention (PCI) procedure.The final percentage of stent diameter stenosis evaluated by quantitative coronary angiography (QCA) at the index procedure after final stent deployment and post-dilatation optimization.
Rate of Procedural ComplicationsDuring the index percutaneous coronary intervention (PCI) procedure (immediate intra-procedural period).The cumulative rate of procedure-related complications during the index procedure, defined as a composite of cardiac death, acute myocardial infarction, emergency coronary artery bypass graft surgery (CABG), coronary artery perforation (Ellis classification), and cardiac tamponade directly related to the use of the Naviscore scoring balloon or the regular non-compliant (NC) balloon.
Procedural Cost-EffectivenessDuring the index percutaneous coronary intervention (PCI) procedure.Evaluation of the procedural cost-effectiveness of using the Naviscore scoring balloon compared to standard non-compliant (NC) balloons for calcified lesion preparation, calculated by factoring device costs, overall material utilisation during the intervention, procedure duration, and the need for bailout additional plaque-modification tools or complementary high-pressure devices.

Countries

Belgium, Luxembourg, Portugal, Spain

Contacts

CONTACTStéphane Carlier, MD, PhD
stephane.carlier@umons.ac.be+3265373381
PRINCIPAL_INVESTIGATORStéphane Carlier, MD, PhD

University of Mons

PRINCIPAL_INVESTIGATORAntonio Serra

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jun 17, 2026