IVUS-Guided vs Angiography-Guided PCI in Acute Coronary Syndrome (SAINT-IVUS)

Clinical Impact of Intravascular Ultrasound-guided vs. Angiography-guided Coronary Stenting in Patients With Acute Coronary Syndrome: Multicenter, Randomized Control Trial (SAINT-IVUS)

Coronary artery disease is associated with substantial morbidity and mortality worldwide. Percutaneous coronary intervention (PCI) is a pivotal procedure for the treatment of coronary artery disease. Although coronary angiography (CA) is the standard imaging modality used for coronary stent implantation, it provides only two-dimensional images of the coronary arteries. Intravascular ultrasound (IVUS) can provide additional information on plaque characteristics and vessel morphology, which may facilitate optimal stent sizing and procedural optimization. However, IVUS requires additional time and cost and may increase procedural complexity. Evidence regarding the clinical benefit of IVUS-guided PCI in patients with acute coronary syndrome (ACS) remains limited.

This study is a prospective, multicenter, randomized controlled trial designed to compare IVUS-guided PCI versus angiography-guided PCI in patients with ACS. A total of 1,500 participants will be randomized 1:1 to either the IVUS-guided group or the angiography-guided group. Participants will be recruited from 15 PCI centers in Korea. The primary outcome is target vessel failure at 2 years.

Study Overview

• Status: Recruiting
• Conditions: Acute Coronary Syndromes (ACS)
• Intervention / Treatment: Procedure: IVUS-guided PCI; Procedure: Angiography-guided PCI

Detailed Description

Coronary artery disease is a condition characterized by a high incidence and mortality rate globally. Percutaneous coronary intervention (PCI) stands as a pivotal procedure in the diagnosis and treatment of this disease. Although coronary angiography (CA) is the standard imaging used in coronary stent implantation, it has a limitation in that it only provides two-dimensional images of the coronary arteries. To overcome this limitation, intravascular ultrasound (IVUS) can be utilized, allowing for the visualization of three-dimensional images such as intravascular plaque and morphological characteristics within the vessel, thereby offering more detailed information essential for optimal stent placement. Theoretically, IVUS-guided drug-eluting stent insertion could bring about a reduction in major cardiac events in patients with complex lesions and those at high risk, but most studies have excluded patients with acute coronary syndrome (ACS). The utilization of IVUS demands additional costs and time and might escalate the risk of intravascular complications in certain circumstances. However, the use of IVUS can facilitate a more accurate evaluation of plaque properties and morphology, assisting in determining more effective treatment strategies, and potentially contributing to lowering the risk of major cardiac events in patients suffering from acute myocardial infarction.

The objective of this study is to observe and compare the clinical impact between IVUS-guided drug-eluting stent insertion and angiography-guided drug-eluting stent insertion in patients with ACS over a span of 24 months. To this end, the investigators have planned a prospective, multi-institutional, randomized controlled trial, setting the primary outcome measurement as the target vessel failure rate over two years. The study will encompass 1500 patients, who will be assigned randomly at a 1:1 ratio to either the IVUS-guided or angiography-guided groups. The study participants will be recruited from 15 leading domestic PCI centers.

This research intends to chart the future course of ACS treatment, aspiring to surmount the current limitations of the technologies being employed. It is anticipated that in patients with ACS, IVUS-guided stent insertion during drug-eluting stent implantation might present superior clinical long-term prognoses compared to simple angiography-guided insertion.

• Study Type: Interventional
• Enrollment (Estimated): 1500
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: SUK MIN SEO, Assisted Professor; Phone Number: 82+010-9090-8491; Email: ssm530@catholic.ac.kr
• Study Contact Backup: Name: YUN JU KANG, RN,CRC; Phone Number: 82+010-7358-5252; Email: yunju423@naver.com

Study Locations

• South Korea
  • Eunpyeong-gu
    • Seoul, Eunpyeong-gu, South Korea, 03312
      • Recruiting
      • The Catholic University of Korea, Eunpyeong St. Mary's Hospital
      • Contact: SUK MIN SEO, Assisted Professor; Phone Number: 82+010-9090-8491; Email: ssm530@catholic.ac.kr
      • Contact: YUN JU KANG; Phone Number: 82+010-7358-5252; Email: yunju423@naver.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patients 19 years of age or older
2. Patients with unstable angina pectoris, and acute MI including NSTEMI or STEMI.
3. Coronary artery disease defined as >70% stenosis (reference vessel diameter 2.5 - 5.0 mm based on operator assessment) with identifiable culprit lesion indicated stent implantation
4. All lesions must be suitable for treatment with the Synergy stent system, or other Synergy platform iteration
5. The patient or guardian agrees to the study protocol and the schedule of clinical and angiographic follow-up, and provides informed, written consent, as approved by the appropriate Institutional Review Board/Ethical Committee of the respective clinical site.

Exclusion Criteria:

1. Age >90 years
2. Subject has known hypersensitivity or contraindication to device material and its degradants (everolimus, poly(L-lactide), poly(DL-lactide), lactide, lactic acid) and cobalt, chromium, nickel, platinum, tungsten, acrylic, and fluoro polymers that cannot be adequately premedicated.
3. Absolute contraindications or allergy that cannot be pre-medicated, to iodinated contrast or to antiplatelet drugs, including both aspirin and P2Y12 inhibitors
4. An elective surgical procedure is planned that would necessitate interruption of antiplatelet drugs within 6 m after the procedure.
5. Cardiogenic shock
6. Restenotic lesions
7. Compromised left ventricular dysfunction (LVEF <30%)
8. At the time of screening, the subject has a malignancy that is not in remission
9. Non-cardiac co-morbidities with a life expectancy less than 1 year
10. Patients who are actively participating in another drug or device investigational study, which have not completed the primary endpoint follow-up period.
11. Subject belongs to a vulnerable population (per investigator's judgment) or subject unable to read or write
12. Concern for inability of the patient to comply with study procedures and/or follow-up (e.g., alcohol or drug abuse)
13. Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: IVUS-guided PCI; PCI will be performed under IVUS guidance. Post-stent IVUS assessment is mandatory, and procedural optimization will be performed according to predefined IVUS criteria. Additional balloon dilation or stent implantation may be performed at the operator's discretion if optimization criteria are not met.	Procedure: IVUS-guided PCI; Patients randomized to the IVUS-guided PCI arm will undergo percutaneous coronary intervention with intravascular ultrasound guidance. IVUS may be used before, during, and after PCI, and post-stent IVUS assessment will be mandatory. IVUS will be used to determine reference vessel dimensions, guide stent sizing and length selection, and optimize stent expansion and apposition according to predefined criteria. Optimization criteria include adequate stent expansion (minimal lumen area ≥90% of the average reference lumen area), absence of major malapposition, absence of major edge dissection, and absence of significant residual stenosis near the stent edges. If these criteria are not met, additional balloon dilation or stent implantation may be performed at the operator's discretion.
Active Comparator: Angiography-guided PCI; PCI will be performed under coronary angiography guidance. Routine IVUS use is not planned. IVUS may be used only for bailout situations at the operator's discretion.	Procedure: Angiography-guided PCI; Patients randomized to the angiography-guided PCI arm will undergo percutaneous coronary intervention guided by conventional coronary angiography. Stent sizing, length selection, and procedural optimization will be performed according to standard angiographic assessment at the operator's discretion. Routine use of intravascular ultrasound will not be routinely performed in this group. However, IVUS may be used only in bailout situations if deemed necessary by the operator.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Target Vessel Failure (TVF)	Composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization.	2 years after randomization

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cardiac death	Death resulting from immediate cardiac causes including myocardial infarction, heart failure, arrhythmia, or other cardiac conditions	2 years after randomization
Target vessel-related myocardial infarction	Myocardial infarction attributable to the target vessel treated during the index PCI according to the Fourth Universal Definition of Myocardial Infarction.	2 years after randomization
Clinically driven target vessel revascularization	Repeat percutaneous coronary intervention or coronary artery bypass grafting of the target vessel due to symptoms or objective evidence of myocardial ischemia.	2 years after randomization
All-cause death	Death from any cause.	2 years after randomization
Rate of participants with myocardial infarction (periprocedural MI or spontaneous MI)	Myocardial infarction defined according to the Fourth Universal Definition of Myocardial Infarction.	2 years after randomization
Rate of participants with any coronary revascularization	target vessel vs. non-target vessel, target lesion vs. non-target lesion, clinically driven vs. non-clinically driven	2 years after randomization
Rate of participants with definite or probable stent thrombosis	Definite or probable stent thrombosis defined according to the Academic Research Consortium (ARC) criteria.	2 years after randomization
Procedural success	Successful PCI with residual stenosis <30% and final TIMI 3 flow in the treated vessel without in-hospital major adverse cardiac events.	Periprocedural (index PCI)
Total procedural time		Periprocedural (index PCI)
Total amount of contrast use		Periprocedural (index PCI)
Incidence of contrast-induced nephropathy, defined as an increase in serum creatinine of ≥0.5mg/dL or ≥25% from baseline within 48-72 hours after contrast agent exposure		72 hours after index procedure

Collaborators and Investigators

• Sponsor: SUK MIN SEO
• Collaborators: Boston Scientific Korea Co. Ltd
• Investigators: Principal Investigator: Suk Min Seo, MD, PhD, The Catholic University of Korea Eunpyeong St. Mary's Hospital

Publications and helpful links

General Publications

• Schiele F, Meneveau N, Vuillemenot A, Zhang DD, Gupta S, Mercier M, Danchin N, Bertrand B, Bassand JP. Impact of intravascular ultrasound guidance in stent deployment on 6-month restenosis rate: a multicenter, randomized study comparing two strategies--with and without intravascular ultrasound guidance. RESIST Study Group. REStenosis after Ivus guided STenting. J Am Coll Cardiol. 1998 Aug;32(2):320-8. doi: 10.1016/s0735-1097(98)00249-6.
• Darmoch F,Alraies MC,Al-Khadra Y,Moussa Pacha H,Pinto DS,Osborn EA

Study record dates

Study Major Dates

• Study Start (Actual): March 13, 2025
• Primary Completion (Estimated): December 31, 2030
• Study Completion (Estimated): December 31, 2031

Study Registration Dates

• First Submitted: March 13, 2026
• First Submitted That Met QC Criteria: April 2, 2026
• First Posted (Actual): April 6, 2026

Study Record Updates

• Last Update Posted (Actual): April 6, 2026
• Last Update Submitted That Met QC Criteria: April 2, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Intravascular Ultrasound; IVUS-guided PCI; Angiography-guided PCI
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Heart Diseases; Myocardial Ischemia; Acute Coronary Syndrome
• Other Study ID Numbers: PC23EIDE0191; KCT0009756 (Registry Identifier: Clinical Research information Service, CRIS)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be publicly available because of institutional policy and patient confidentiality considerations.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No