Thrombus aspiration and OCT comparison in acute coronary syndromes

Pathologic Features of Aspirated Athero-Thrombotic Material From OCT-Verified Culprit Lesion in Acute Coronary Syndrome (TAPOS)

This project will test whether material suctioned from clots during PCI matches OCT imaging findings in people with acute coronary syndrome (STEMI or NSTEMI).

Quick facts

• Study type: Observational
• Enrollment: 200 (estimated)
• Ages: 20 Years and up
• Sex: All
• Sponsor: Fujita Health University (Academic / other)
• Locations: 1 site (Toyoake, Aichi-ken)
• Trial ID: NCT07151976 on ClinicalTrials.gov

What this trial studies

This observational effort compares the microscopic makeup of thrombus material aspirated during PCI with pre-PCI optical coherence tomography (OCT) images of the culprit plaque in patients presenting with STEMI or NSTEMI. Thrombus is collected during aspiration and processed for blinded pathology review, while OCT images are read independently to classify plaques as ruptured fibrous cap, intact fibrous cap (erosion), or calcified nodule. The primary aim is to determine whether aspirated material from OCT-defined ruptures contains plaque components (cholesterol clefts, foam cells, cap fragments, calcifications) while aspirates from erosions contain only thrombus. Secondary aims include characterizing M1/M2 macrophage presence in samples with plaque material and comparing short- and long-term clinical outcomes by imaging and pathology categories.

Who should consider this trial

Good fit: Ideal participants are adults with STEMI or NSTEMI who undergo PCI of a native coronary culprit lesion with both pre-PCI OCT imaging and thrombus aspiration and can provide informed consent.

Not a fit: Patients in cardiogenic shock, those with contraindications to anticoagulation or antiplatelet therapy, or those with lesions in tortuous vessels, ostial segments, or the left main are excluded and unlikely to receive benefit from this protocol.

Why it matters

Potential benefit: If successful, this work could improve clinicians' confidence in OCT imaging to distinguish plaque rupture from erosion and help guide more targeted treatment during PCI.

How similar studies have performed: Previous OCT-pathology and in vivo OCT series have supported the relative frequencies of rupture versus erosion and shown partial correlation, but direct blinded comparisons of aspirated thrombus composition versus OCT-defined plaque types are limited.

Eligibility criteria

Inclusion Criteria:

1. Patients with ACS showing ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI) are studied.
2. Only native coronary artery lesions are included in the study.
3. Optical coherence tomography (OCT) was performed prospectively to compare OCT culprit lesions characteristics with histological analysis of athero-thrombotic aspirated material of the culprit lesion. For this purpose, only lesions with both athero-thrombotic aspirated material and OCT observations are included in the study.
4. All patients provided written informed consent for the index procedure, follow-up, and anonymous data management.

Exclusion Criteria:

1. Patients are excluded from the study when they had cardiogenic shock and contraindications to anticoagulation and anti-platelet therapy.
2. Lesions located in tortuous vessels, in ostial segment and in the left main stem are excluded from the study due to the difficulty in performing high-quality intracoronary imaging.

Where this trial is running

Toyoake, Aichi-ken

• Fujita Health University — Toyoake, Aichi-ken, Japan (Recruiting)

Study contacts

• Principal investigator: YUKIO OZAKI, MD, PhD — Fujita Health University, Aichi, Japan
• Study coordinator: Yukio Ozaki, MD, PhD

Conditions Acute Coronary Syndrome