Application of Index of Microcirculatory Resistance to Evaluate Myocardial Protection After Ischemic Adaptation

Study Overview
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Brief Summary
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To evaluate the protective effect of IPC on the myocardial microcirculation response through IMR and the predictive value of IMR on the degree of myocardial reperfusion and the prognosis of patients.

Detailed Description
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This study is a clinical randomized controlled study, applying index of microcirculatory resistance (IMR) to evaluate the myocardial protection of ischemic postconditioning (IPC) in patients receiving direct PCI treatment for acute myocardial infarction.IMR is a quantitative evaluation index of microcirculation status. IPC has been reported to reduce ischemia-reperfusion injury and has a myocardial protective effect.The research plan divides patients into IPC and non-IPC groups at random. After the infarction-related artery is successfully implanted with a stent, the pressure guide wire is used to measure IMR and CFR in the state of maximal expansion of the microcirculation induced by intravenous ATP infusion.And analyze whether there are differences in indicators between the two groups and the relationship between these indicators and the patient's myocardial level reperfusion, cardiac function and prognosis.The purpose is to evaluate the myocardial protection of IPC and the predictive value of IMR on the degree of myocardial reperfusion and the prognosis of patients. It is expected that the target IPC can improve the IMR value, and IMR can predict the degree of myocardial reperfusion and cardiac function and prognosis.

Official Title
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Application of Index of Microcirculatory Resistance to Evaluate Myocardial Protection After Ischemic Adaptation

Conditions
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Acute Myocardial Infarction

Intervention / Treatment
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* Procedure: IPC+PCI
* Procedure: No IPC


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years old, no gender limit; First episode of STEMI (diagnostic criteria: ischemic chest pain lasting ≥30min; ST-segment elevation in two or more adjacent leads on the ECG or new left bundle branch block; with or without elevated myocardial markers), The onset time is within 12 hours, and emergency interventional treatment is planned; Agree and cooperate to participate in this research. Exclusion Criteria: Old myocardial infarction; Killip grade of cardiac function ≥ grade III or cardiogenic shock; Systolic blood pressure ≤100mmHg; Bradycardia, HR<60pbm, or AVB above II degree; Past history of asthma or severe COPD; Severe liver and kidney dysfunction.

Ages Eligible for Study
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Minimum Age: 18 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: Ischemic postconditioning<br>Routine PCI operations (including thrombus aspiration, stent injection, application of GPIIb/IIIa, etc.) + immediate post-ischemic adaptation: 30 seconds balloon inflation and 30 seconds deflation for 3 cycles | Procedure: IPC+PCI<br>* Routine PCI operations (including thrombus aspiration, stent injection, application of GPIIb/IIIa, etc.) + immediate post-ischemic adaptation: 30 seconds balloon inflation and 30 seconds deflation for 3 cycles<br>* Other names: Ischemic postconditioning;|
| Active Comparator: No Ischemic postconditioning<br>Routine PCI operations (including thrombus aspiration, stent injection, application of GPIIb/IIIa, etc.) | Procedure: No IPC<br>* Routine PCI operations (including thrombus aspiration, stent injection, application of GPIIb/IIIa, etc.<br>* Other names: Routine PCI;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| IMR | index of microcirculatory resistance measured during coronary intervention. | detected immediately after percutaneous coronary intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| MACEs after PCI | MACEs includes cardiogenic death, non-fatal myocardial infarction, malignant arrhythmia, unplanned revascularization, unstable angina pectoris requiring hospitalization and severe heart failure requiring hospitalization | 6 months |