Early Prediction of QFR in STEMI-I

Study Overview
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Brief Summary
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The study intends to provide important data on whether the noval method using quantitative flow ratio could predict microvascular dysfunction.

Detailed Description
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Microvascular dysfunction (MVD) is a serious complication of PCI, which happens frequently after STEMI and always correlates with a poor prognosis. However, precise and simplified assessment of MVD is difficult, especially in the acute phase of STEMI patients. Resent studies suggested that FFR could be overestimated when MVD exists. But whether the overestimated value of FFR caused by CMR defined MVO could reflect microcirculation function is still unclear. This study is a retrospective study using STEMI patients with TFG 2/3 of the infarct vessel on initial angiography and presumed culprit lesion ≥50% as the population. Contrast-enhanced CMR was performed 5 days after PCI as the reference standard.

Official Title
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EARLY Microvascular Dysfunction Prediction Using Quantitative Flow Ratio After ST-segment Elevation MYOcardial Infarction (EARLY-MYO-QFR I)

Conditions
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ST Segment Elevation Myocardial Infarction

Intervention / Treatment
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* Diagnostic Test: Computation of quantitative flow ratio


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: STEMI patients treated with revasculation within 12 hours from onset of symptoms to PCI time and received CMR 5 days afterwards. STEMI was defined as a combination of the following: chest pain for more than 30min, electrocardiographic (ECG) changing with ST segment elevation of >2 mm in at least 2 precordial leads and >1 mm in limb leads, and abnormal troponin levels or CKMB levels higher than twice the upper limit of normal. Patients with TFG 2/3 in the initial angiography of the culprit vessel. Exclusion Criteria: Patients with left bundle branch block in the presenting ECG, cardiogenic shock, PCI or bypass surgery history. Patients with residual stenosis <50%. Patients with unqualified coronary angiographic images with problems such as ostial lesion, severe vessel tortuosity and diffuse long lesions.
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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| MVO group<br>CMR was performed in all the cases. According to the results of CMR, we divided the study population into MVO group and Non-MVO group. | Diagnostic Test: Computation of quantitative flow ratio<br>* Computation of QFR was performed offline, using AngioPlus system(Pluse medical imaging technology, Shanghai, China). In the first step, 2 diagnostic angiographic projections before PCI, at least 25° apart, were selected and 3D reconstruction of the interrogated vessel without its side branches was performed. Then, the software computed the QFR.<br>|
| Non-MVO group<br>CMR was performed in all the cases. According to the results of CMR, we divided the study population into MVO group and Non-MVO group. | Diagnostic Test: Computation of quantitative flow ratio<br>* Computation of QFR was performed offline, using AngioPlus system(Pluse medical imaging technology, Shanghai, China). In the first step, 2 diagnostic angiographic projections before PCI, at least 25° apart, were selected and 3D reconstruction of the interrogated vessel without its side branches was performed. Then, the software computed the QFR.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiac magnetic resonance (CMR) | Cardiac magnetic resonance (CMR) is a non-invasive test for MVO assessing | Five days after PCI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| TIMI Flow Grade (TFG) | TIMI Flow Grade (TFG) assesses flow in the epicardial arteries. Type zero perfusion expressed not antegrade movement away the occlusion; type two is a minimum, inadequate perfusion of contrast average round the mass; type three (partial perfusion) is a perfect just limited perfusion from the distal coronary bed by contrast element; and type three (complete perfusion) is an antegrade movement to the whole distal artery at a regular flow. | One mins before PCI | 
| TIMI Flow Grade (TFG) | TIMI Flow Grade (TFG) assesses flow in the epicardial arteries. Type zero perfusion expressed not antegrade movement away the occlusion; type two is a minimum, inadequate perfusion of contrast average round the mass; type three (partial perfusion) is a perfect just limited perfusion from the distal coronary bed by contrast element; and type three (complete perfusion) is an antegrade movement to the whole distal artery at a regular flow. | One mins after PCI | 
| TIMI Myocardial Perfusion Grade (TMPG) | TIMI Myocardial Perfusion Grade (TMPG) assesses flow in the micrevessels. TMPG0: no or minimal blush; TMPG1: Stain present Blush persists on next injection; TMPG2: Dye strongly persistent at end of washout Gone by next injection; TMPG3: normal ground glass appearance of blush Dye mildly persistentat end of washout. | One mins before PCI | 
| TIMI Myocardial Perfusion Grade (TMPG) | TIMI Myocardial Perfusion Grade (TMPG) assesses flow in the micrevessels. TMPG0: no or minimal blush; TMPG1: Stain present Blush persists on next injection; TMPG2: Dye strongly persistent at end of washout Gone by next injection; TMPG3: normal ground glass appearance of blush Dye mildly persistentat end of washout. | One mins after PCI | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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STEMI, Cardiac magnetic resonance