Ticagrelor Versus Clopidogrel for CMD in Patients With AMI: A Retrospective Study Based on the Angio-IMR

Study Overview
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Brief Summary
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Coronary microvascular dysfunction (CMD) is increasingly recognized as an important indicator for long-term prognosis in patients with acute myocardial infarction (AMI). The angiography-derived index of microcirculatory resistance (angio-IMR) is a novel guidewire-free measure for CMD in patients with AMI. Ticagrelor has recently been suggested to have additional benefits on coronary microcirculation beyond its antiplatelet effect. This study was designed to compare the protective effects of ticagrelor and clopidogrel on CMD and prognostic impact in patients with AMI, using the angio-IMR as a novel assessment tool.

Official Title
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Ticagrelor Versus Clopidogrel for Coronary Microvascular Dysfunction in Patients With Acute Myocardial Infarction: A Retrospective Study Based on the Angiography-derived Index of Microcirculatory Resistance

Conditions
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Coronary Heart Disease

Intervention / Treatment
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* Drug: Dual antiplatelet therapy with aspirin and either ticagrelor or clopidogrel


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who were diagnosed with AMI, including STEMI and NSTEMI, and underwent successful PCI and routine follow-up coronary angiography at the Second Affiliated Hospital of Zhejiang University School of Medicine between June 1, 2017 and May 31, 2020. Exclusion Criteria: 1) prior treatment with any P2Y12 inhibitor; 2) need for long-term oral anticoagulation therapy; 3) previous coronary artery bypass grafting (CABG); 4) chronic renal dysfunction with estimated glomerular filtration rate (eGFR) <30 mL/ (min·1.73 m2) or on hemodialysis; 5) liver cirrhosis ≥Child-Pugh B class; 6) cancer; 7) adjustment of dual antiplatelet therapy (DAPT) during follow-up; 8) inadequate coronary angiographic images.

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

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ticagrelor maintenance treatment group<br>Patients received dual antiplatelet therapy (DAPT) with aspirin 100mg daily and ticagrelor 90mg twice daily for at least 9 months after PCI. Angio-IMR assessment was performed after primary PCI and during routine follow-up coronary angiography. | Drug: Dual antiplatelet therapy with aspirin and either ticagrelor or clopidogrel<br>* Patients with acute myocardial infarction randomly received dual antiplatelet therapy with with aspirin 100mg daily and either ticagrelor 90mg twice daily or clopidogrel 75mg once daily for at least 9 months after PCI as needed.<br>|
| clopidogrel maintenance treatment group<br>Patients received dual antiplatelet therapy (DAPT) with aspirin 100mg daily and clopidogrel 75mg once daily for at least 9 months after PCI. Angio-IMR assessment was performed after primary PCI and during routine follow-up coronary angiography. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The improvement of angio-IMR | Difference between Angio-IMR at follow-up coronary angiography and Angio-IMR after PCI | within 24 months post-PCI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Readmission for heart failure | Readmission for an acute exacerbation of chronic heart failure or acute heart failure | Within 24 months post-PCI | 
| Myocardial reinfarction | Another myocardial infarction with elevated myocardial enzymes and abnormal electrocardiograms | Within 24 months post-PCI | 
| Target vessel revascularization | Repeat revascularization was performed because of ischemia in the target-vessel territory | Within 24 months post-PCI | 
| Non-target vessel revascularization | Repeat revascularization was performed because of ischemia in the non-target vessel territory | Within 24 months post-PCI | 
| Cerebral hemorrhage | The occurrence of cerebral hemorrhage during the follow-up period was based on imaging CT and MRI | Within 24 months post-PCI | 
| Other bleeding events | Bleeding events such as gingival bleeding, skin bleeding, and gastrointestinal bleeding and so on, occurred during the follow-up period | Within 24 months post-PCI |