Angio-based Fractional Flow Reserve to Predict Adverse Events After Stent Implantation

Study Overview
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Brief Summary
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The investigators will collect prospectively baseline, procedural and follow-up data of all patients receiving successful percutaneous coronary intervention (PCI) and stent implantation. Angio-based flow fractional reserve (quantitative flow ratio, QFR, Medis medical imaging systems Leiden, The Netherlands) will be estimated in all patients. Especially, the investigators at the end of the procedure (this is defined according operator's judgement) will record 2 orthogonal angiograms (as suggested by QFR instructions) at 15 frames/second and the same 2 orthogonal angiograms at 30 frames/second. An independent corelab (blinded to procedural data and clinical outcome) will estimate QFR value (one with the angiograms at 15 frames and one with those at 30 frames

Detailed Description
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Fractional flow reserve (FFR) allows to evaluate the functional significance of coronary artery lesions, through the ratio of the mean coronary artery pressure after the stenosis to the mean aortic pressure during maximum hyperaemia. The actual widely accepted cutoff value is 0.80. Below this value, an intermediate coronary lesion is considered significant and its treatment with percutaneous coronary intervention (PCI) is justified. The measurement FFR after stent implantation has a strong predictive value with respect to death, myocardial infarction, or need for repeat revascularization of the target vessel within 6 months. The higher the FFR, the lower the event rate. FFR cut-off of 0.90 might be a useful indicator in daily practice for optimal physiologic stent implantation. Nevertheless, the use of the FFR in the post stenting , is relatively low, because of costs of the pressure wire and the adverse effects related to the use of adenosine. A new method (QFR by Medis medical imaging) for evaluation of the functional significance of coronary stenosis is based on computer calculation of the FFR value. This calculation is performed by analysing the coronary angiogram and thus reduces or potentially eliminates the need for measuring FFR by pressure wires. The QFR method combines a 3D reconstructions of the target vessel based on two angiographic projections and the contrast flow velocity to compute the FFR value. To perform QFR the investigators will acquire two angiographic projections with angle >25 degree that allow the 3D reconstruction of the vessel (see values below). Projections for left main (LM) and proximal left anterior descending (LAD) or proximal left circumflex (LCX): right anterior oblique (RAO) 20, Caudal 45 and anterior-posterior (AP), Caudal 10 Projections for LAD/diagonal: AP, Cranial 45 and RAO 35, Cranial 20 Projections for LCX/obtuse marginal (OM): left anterior oblique (LAO) 10, Caudal 45 and RAO 25, Caudal 25 Projections for Proximal+Mid right coronary artery (RCA): LAO 45, caudal (CAUD) 0 and AP, CAUD 0 Projections for postero-lateral artery and posterior-descending artery (PLA/PDA): LAO 45, CAUD 0 and LAO 30, CAUD 30 Finally, the investigators will assess the relationship between QFR value and adverse events. We will assess the best QFR value able to discriminate the cumulative occurrence of adverse events. In the study, we will include also ST-segment elevation myocardial infarction patients. This subset of patients will be analysed as independent cohort to obtain preliminary results and will be analysed in a independent study

Official Title
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Prospective Validation of the Angio-based Fractional Flow Reserve (Quantitative Flow Ratio, QFR) System to Discriminate Patients at Risk of Adverse Events After Stent Implantation.

Conditions
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Prognosis, Stents

Intervention / Treatment
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* Other: angio-based FFR estimation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: -successfull percutaneous coronary intervention and stent implantation Exclusion Criteria: inability to provide consent inability to guarantee at least 1-year follow-up thrombolysis in myocardial infarction (TIMI) flow <3 life expectancy <1 year previous coronary artery bypass graft atrial fibrillation ongoing ventricular arrhythmias significant and persistent tachycardia (heart rate >100 bpm)

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| angio-based FFR estimation<br>The investigators will include all patients receiving successful coronary stent implantation. In these patients the investigators will acquire specific angiograms to permit angio-based FFR (QFR) calculation. An independent corelab will estimate the QFR value. This value will be related to prognosis to verify if it is able to discriminate those at higher risk of adverse events. | Other: angio-based FFR estimation<br>* The investigators will acquire specific angiograms to permit angio-based FFR (QFR) calculation. An independent corelab will estimate the QFR value. This value will be related to prognosis to verify if it is able to discriminate those at higher risk of adverse events.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Device-oriented cardiac events | cumulative occurrence of cardiac death, target vessel myocardial infarction, target lesion revascularization | 1-year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| cardiac death | cumulative occurrence of cardiac death | 1-year | 
| all-cause mortality | cumulative occurrence of all-cause mortality | 1-year | 
| any myocardial infarction | cumulative occurrence of any myocardial infarction | 1-year | 
| target vessel revascularization | cumulative occurrence of target vessel revascularization | 1-year | 
| stent thrombosis | cumulative occurrence of definite, probable and possible stent thrombosis | 1-year | 
| hospital admission for all causes | cumulative occurrence of hospital admission for all causes | 1-year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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drug eluting stents, flow fractional reserve, prognosis, angio-based FFR