Evaluate Early Invasive Strategy for Patients With STEMI Presenting 24-48 Hours From Symptom Onset

Study Overview
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Brief Summary
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The primary objective of the trial is to evaluate the efficacy of early invasive strategy for STEMI patients within 24-48h of symptom onset.

Detailed Description
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At present, timely primary percutaneous coronary intervention (PCI) is the preferred strategy for ST-segment elevation myocardial infarction (STEMI) patients within 24h of symptom onset. In stable STEMI patients presenting 12 to 48 hours from symptom onset, BRAVE-2 Trial (n = 365) showed improved myocardial salvage and 4-year survival in patients treated with primary PCI compared with conservative treatment alone. However, data is scarce about the reperfusion strategy focusing on STEMI patients within 24-48h of symptom onset. Further investigations are warranted to explore the best timing of invasive strategy for STEMI patients within 24-48h of symptom onset. Given that no randomized clinical trial is designed especially for STEMI patients within 24-48h of symptom onset, and limited data is available to evaluate the efficacy of early invasive strategy for the special subgroup of STEMI patients, investigators plan to perform a controlled, randomized trial to evaluate the efficacy of early invasive strategy for STEMI patients within 24-48h of symptom onset.

Official Title
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A Randomized Multicenter Trial to Evaluate Early Invasive Strategy for Patients With Acute ST-segment Elevation Myocardial Infarction Presenting 24-48 Hours From Symptom Onset

Conditions
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ST-segment Elevation Myocardial Infarction (STEMI)

Intervention / Treatment
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* Procedure: Primary PCI
* Other: Optimal medical therapy with primary PCI not performed


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age: 18 or over and less than 75 years old; ECG: a) ≥2 mm ST-segment elevation in 2 contiguous precordial leads or ≥1 mm ST-segment elevation in 2 contiguous extremity leads; or b) new or presumable new left bundle branch block in the presence of typical symptoms; Patents with STEMI with symptom onset between 24 and 48 hours before randomization; Signed informed consent form prior to trial participation. Exclusion Criteria: Patents with STEMI with symptom onset <24h or >48h or uncertain time onset. Prior administration of thrombolytic therapy or attempted PCI before randomization; Presence of indications for primary PCI, such as persistent chest pain, cardiogenic shock, life-threatening arrhythmias or cardiac arrest, severe acute heart failure, and mechanical complications; Coagulopathy, active peptic ulcer, history of cerebral or subarachnoid hemorrhage, stroke within 6 months, other contraindications for antiplatelet or anticoagulant therapy; Known intolerance to antiplatelet (e.g. aspirin, clopidogrel, ticagrelor) and anticoagulant therapy (e.g. heparin, bivalirudin); Presence of contraindications for CMR; Congenital heart disease or severe valvular disease; eGFR <30 ml/min/1.73 m2; History of malignant tumors; Combined with other diseases and life expectancy ≤12 months; Pregnancy; Inclusion in another clinical trial; Inability to provide informed consent or not available for follow-up judged by investigator.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Early Invasive Strategy<br>Procedure: Primary PCI | Procedure: Primary PCI<br>* The patients assigned to early invasive strategy group will receive the primary PCI.<br>|
| Active Comparator: Conservative Strategy<br>Procedure: Optimal medical therapy with primary PCI not performed. | Other: Optimal medical therapy with primary PCI not performed<br>* The patients assigned to conservative strategy group will receive optimal medical therapy before primary endpoint accomplished.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Myocardial infraction size assessed by cardiac magnetic resonance (CMR) | Late gadolinium enhancement (LGE) by CMR is performed for myocardial infarction size quantification. | 7 days (from symptom onset) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| A composite of cardiac death, recurrent myocardial infarction, ischaemia-driven target vessel revascularization, and stoke |  | 30 days | 
| Microvascular obstruction (MVO) assessed by CMR | Serial imaging sequence results from CMR. | 7 days (from symptom onset) | 
| Intramyocardial hemorrhage (IMH) assessed by CMR | Serial imaging sequence results from CMR. | 7 days (from symptom onset) | 
| Area at risk (AAR) assessed by CMR | Serial imaging sequence results from CMR. | 7 days (from symptom onset) | 
| Left ventricular ejection fraction (LVEF) assessed by CMR | Imaging parameters from CMR. | 7 days (from symptom onset) | 
| Left ventricular end-diastolic volume (LVEDV) assessed by CMR | Imaging parameters from CMR. | 7 days (from symptom onset) | 
| Left ventricular end-systolic volume (LVESV) assessed by CMR | Imaging parameters from CMR. | 7 days (from symptom onset) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ST-segment Elevation Myocardial Infarction (STEMI), Early Invasive Strategy