Stable Angina, Coronary Artery Disease
Conditions
Keywords
Optical coherence tomography, stable angina, dual antiplatelet therapy, stent optimization, percutaneous coronary intervention
Brief summary
This study aims to evaluate whether the use of optical coherence tomography (OCT), an advanced intravascular imaging tool, can improve stent implantation results and make it possible to shorten the duration of dual antiplatelet therapy (DAPT) in patients with stable angina who undergo percutaneous coronary intervention (PCI). PCI with drug-eluting stents is a standard treatment for patients with stable angina, and these patients are usually prescribed DAPT for 6 to 12 months to prevent stent thrombosis and other complications. However, extended use of DAPT increases the risk of bleeding, which can lead to significant medical problems, especially in patients with high bleeding risk. OCT provides detailed, high-resolution images of the coronary arteries and the implanted stents, allowing physicians to optimize stent expansion and positioning. By ensuring that the stent is well-placed and fully expanded, OCT guidance may lower the risk of complications, potentially reducing the need for prolonged DAPT. In this prospective study, patients with stable angina who require stent implantation will be enrolled and treated with OCT-guided PCI followed by a short course of DAPT. Their outcomes will be compared with those managed using conventional strategies. The primary goal of this trial is to determine whether OCT-guided stent optimization can safely support a short-duration DAPT strategy, thereby reducing bleeding risk without compromising protection against ischemic events such as restenosis, myocardial infarction, or stent thrombosis.
Detailed description
Ischemic heart disease (IHD) remains one of the leading causes of death worldwide, and more than 80% of deaths from coronary artery disease (CAD) occur in individuals aged 65 years or older. Elderly patients often have multiple comorbidities, such as diabetes mellitus, hypertension, and chronic kidney disease, which increase both ischemic and bleeding risks. For these patients, the management of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) is particularly challenging, as physicians must balance ischemic protection against the risk of bleeding complications. Optical coherence tomography (OCT) provides high-resolution intravascular imaging that allows precise assessment of stent apposition, expansion, and the presence of dissections. Previous studies, including Kubo et al. (2022), have proposed OCT-based criteria for stent optimization, demonstrating that inadequate stent expansion or a minimum lumen area (MLA) \< 4.5 mm² is associated with worse outcomes. However, to date, few clinical studies have directly evaluated whether OCT-guided stent optimization can support individualized adjustment of DAPT duration. The COMFORT-SHORT study is a prospective, single-center, open-label pilot registry designed to investigate the safety and feasibility of OCT-guided stent optimization in applying short-term DAPT strategies. Patients with stable angina undergoing PCI with drug-eluting stent implantation will be enrolled. All participants will undergo OCT during PCI to evaluate stent deployment. Stent size and length will be determined based on OCT analysis, and final imaging will be reviewed to confirm whether the procedure meets predefined optimization criteria. Patients whose stents are confirmed as optimized will be transitioned to 1 month of DAPT followed by clopidogrel monotherapy. Patients with suboptimal results (e.g., malapposition, medial dissection, under-expansion) will continue standard DAPT for 6-12 months, based on guideline recommendations and individual bleeding. Importantly, patients with non-optimized stents will not be excluded; they will be followed prospectively, and outcomes will be compared with those of optimized patients. The primary endpoint is the incidence of net adverse clinical events (NACE) at 12 months, comparing short-term versus standard DAPT strategies according to stent optimization status. All enrolled patients will undergo scheduled follow-up at 1, 6, and 12 months after PCI.
Interventions
Patients receive aspirin and clopidogrel for 1 month after PCI. After 1 month, aspirin is discontinued and clopidogrel monotherapy is continued.
Patients with high bleeding risk will receive aspirin and clopidogrel for 6 months after PCI (unoptimization confirmed in OCT), followed by single antiplatelet therapy thereafter.
Patients (with stet unoptimazation results in OCT imaging) receive aspirin and clopidogrel for 12 months after PCI.
All patients undergo percutaneous coronary intervention with mandatory intravascular imaging using optical coherence tomography to assess stent optimization (expansion, apposition, dissection).
Sponsors
Study design
Intervention model description
This is a prospective, single-center, open-label study with a parallel assignment design. All patients undergo OCT-guided PCI. Based on OCT findings, patients are categorized into two groups: those with optimized stent results receive short-duration DAPT (1 month), while those with suboptimal stent results continue standard DAPT (6-12 months) according to guidelines. Outcomes will be compared between groups.
Eligibility
Inclusion criteria
* Patients who undergo PCI using a cobalt-chromium everolimus-eluting stent (CoCr-EES) * Diagnosis of stable angina * Ability and willingness to provide written informed consent approved by the Institutional Review Board (IRB), and to comply with the study protocol and clinical follow-up schedule * Age ≥ 19 years
Exclusion criteria
* Patients diagnosed with acute coronary syndrome (ACS), including unstable angina or acute myocardial infarction * Contraindications to antiplatelet therapy or OCT imaging * Presence of lesions with severe stenosis, heavy calcification, or marked vessel tortuosity that prevent passage of a guidewire or catheter * Patients with previously implanted coronary stents in the target lesion
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Net Adverse Cardiovascular Events (NACE) | 12 months after the index PCI | Composite of cardiac death, non-fatal myocardial infarction, definite/probable stent thrombosis (ARC definition), stroke, repeat coronary revascularization, or clinically significant bleeding defined as BARC types 2, 3, or 5. Analyses will use time-to-first-event; each component will also be summarized separately as secondary outcomes per protocol. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Major Adverse Cardiovascular Events (MACE) | 12 months after PCI | Composite of cardiac death, non-fatal myocardial infarction, definite/probable stent thrombosis (ARC), repeat coronary revascularization, or stroke (time-to-first-event). |
| All bleeding events | 12 months after the index PCI | Any bleeding by BARC criteria (types 1-5). |
| All-cause death | 12 months after the index PCI | Death from any cause. |
| Repeat revascularization | 12 months | Any coronary revascularization (PCI or CABG), including TLR/TVR as defined in the protocol. |
| Myocardial infarction | 12 months after the index PCI | MI defined per protocol-specified criteria (e.g., Fourth Universal Definition of MI); adjudicated events will be counted. |
| Stent thrombosis | 12 months | Definite or probable stent thrombosis per ARC definitions. |
| Stroke | 12 months | Ischemic or hemorrhagic stroke confirmed by clinical assessment and/or neuroimaging, with a new focal neurologic deficit lasting \>24 hours or resulting in death. |
| Cardiac death | 12 months after the index PCI | Death due to cardiac causes (e.g., MI, sudden cardiac death, heart failure), per protocol definition. |
Countries
South Korea