Early Initiation of Low Dose Tirofiban for PPCI in STEMI Patients.

Study Overview
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Brief Summary
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Anti-platelet therapy is a key point of acute myocardial infarction (AMI) treatment. Nowadays, dual anti-platelet therapy based on aspirin and ADP-P2Y12 receptor inhibitor is the preferred treatment before primary percutaneous coronary intervention (PPCI). Restricted by pharmacokinetic and pharmacodynamic characteristics, ADP-P2Y12 receptor inhibitors cannot take effect immediately after oral administration. However, platelet glycoprotein Ⅱb / Ⅲa inhibitors take effect faster. Previous clinical trials indicated that combination of full dose of glycoprotein Ⅱb / Ⅲa inhibitor and dual anti-platelet therapy reduced AMI related ischemia events but increased bleeding events significantly. The high dose of glycoprotein Ⅱb / Ⅲa inhibitor may be the key factor contributing to the increased bleeding events. Therefore, this study aims to evaluate the effectiveness and security of triple anti-platelet therapy based on a small dose of glycoprotein Ⅱb / Ⅲa inhibitor, aspirin and ADP-P2Y12 receptor inhibitor in AMI patients receiving PPCI.

Official Title
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Early Initiation of Low Dose Tirofiban for Primary Percutaneous Coronary Intervention in Patients With ST-segment Elevation Myocardial Infarction.

Conditions
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ST Elevation Myocardial Infarction

Intervention / Treatment
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* Drug: Tirofiban
* Drug: Normal saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Time after onset of chest pain: ≥ 30 minutes and ≤ 24 hours; ST segment elevated ≥ 0.1mV in adjacent two or more leads; Scheduled for primary percutaneous coronary intervention without contraindications; Written informed consent is obtained. Exclusion Criteria: Life expectancy ≤ 1 year; History of cerebral hemorrhage; History of stroke in 6 months; Active hemorrhage; Severe hepatic and renal dysfunction(ALT > 3 folds of upper limit of normal, eGFR < 30ml/min/1.73mm^2 or Scr > 200 mmol/L); Known hemorrhagic diseases; Known malignant tumour diseases； Active peptic ulcer disease; Blood platelet counts < 100×10^9/L; Blood hemoglobin < 90g/L; Pregnancy or lactation period； Take part in other intervention clinical trials； Investigators think not suitable to participate in this trial.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Normal saline<br> | Drug: Normal saline<br>* Upon being diagnosed as ST Elevation Myocardial Infarction, if informed consent is obtained, patients start to receive normal saline intravenous drip in a dosage of 4ml/hour (patients weight<50kg) or 6ml/hour (patients weight > 50kg) lasting for 24 hours.<br>* Other names: Sodium Chloride Injection;|
| Experimental: Tirofiban<br> | Drug: Tirofiban<br>* Upon being diagnosed as ST Elevation Myocardial Infarction, if informed consent is obtained, patients start to receive Tirofiban(0.05mg/ml) intravenous drip in a dosage of 4ml/hour (patients weight<50kg) or 6ml/hour (patients weight > 50kg) lasting for 24 hours.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| TFG(TIMI flow grades) grade III: complete myocardial perfusion immediately after primary percutaneous coronary intervention detected by DSA(Digital Substraction Angiography). | TIMI flow grades: grade III. | Immediately after primary percutaneous coronary intervention. | 
| TMP(TIMI myocardial perfusion grades) grade III: complete myocardial perfusion immediately after primary percutaneous coronary intervention detected by DSA(Digital Substraction Angiography). | TIMI myocardial perfusion grades: grade III. | Immediately after primary percutaneous coronary intervention. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Remedial Tirofiban intravenous use during primary percutaneous coronary intervention procedure. | Remedial Tirofiban use during primary percutaneous coronary intervention. | During the process of primary percutaneous coronary intervention. | 
| ST segment | The sum of the initial ST segment elevation drops 70% or more. | 90 minutes after primary percutaneous coronary intervention. | 
| Myocardial microcirculation perfusion estimated by cardiac magnetic (CMR). | Myocardial microcirculation perfusion estimated by cardiac magnetic resonance imaging. | 7 days after primary percutaneous coronary intervention. | 
| Major adverse cardiovascular events(MACE), including a composite of all-cause death, nonfatal myocardial infarction, stroke, target vessel revascularization. | Major adverse cardiovascular events, including a composite of all-cause death, nonfatal myocardial infarction, stroke, target vessel revascularization. | 30 days after primary percutaneous coronary intervention. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ST Elevation Myocardial Infarction, Tirofiban, Percutaneous Coronary Intervention