Simplified Anti-Thrombotic Therapy for FFR

Study Overview
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Brief Summary
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Despite the routine use of procedural anti-coagulation and anti-platelet therapy for FFR calculation, no study has evaluated the optimal anti-thrombotic regimen in patients undergoing FFR. Therefore, the aim of the Evaluation of Simplified Anti-Thrombotic Therapy for Coronary Fractional Flow Reserve (SMART-FFR) study was to evaluate the safety of using a simplified anti-thrombotic regimen with only upstream dual anti-platelet therapy (DAT) with aspirin and clopidogrel, compared with anticoagulation plus single- or- DAT therapy in patients with intermediate coronary artery stenosis undergoing FFR calculation during elective coronary angiography.

Official Title
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Evaluation of Simplified Anti-Thrombotic Therapy for Coronary Fractional Flow Reserve

Conditions
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Coronary Artery Disease

Intervention / Treatment
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* Procedure: FFR
* Drug: Aspirin
* Drug: Clopidogrel
* Drug: Bivalirudin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patient regardless of sex, or age were eligible for the study if they were scheduled for an elective coronary angiography using a femoral approach, and were agreeable to participate in the study after signing informed consent, and had a coronary stenosis in any major native epicardial coronary artery between 50-70% determined by quantitative angiography that was an adequate target for FFR at the discretion of the operator. Exclusion Criteria: Exclusion criteria included patients requiring mandatory DAT, patient undergoing radial access due to concomitant anticoagulation, patients with contra-indications or intolerant to DAT, patients with severe left ventricular hypertrophy defined as a wall thickness greater than 14 mm by echocardiography in the septal or lateral wall, patients with hypertrophic cardiomyopathy, left ventricular function less than 30%, severe aortic valvular stenosis defined as an aortic valve area of less than 1 cm2, presenting with an acute coronary syndrome in the past two weeks, hemodynamic instability, cardiogenic shock, reported allergy to clopidogrel, aspirin or bivalirudin, planned to be anticoagulated during or previous to the time of the coronary angiography, using Prasugrel or Ticagrelor, patients with coronary arteries unsuitable for FFR calculation due to severe tortuousity and/or calcification, lesions supplied by a bypass conduit, any mental condition rendering the subject incapable to understand the nature, scope, and possible consequences of the study such that the patient is unable to give appropriate informed consent or refusal or inability to sign an informed consent .

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: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group 1<br>Received upstream aspirin plus clopidogrel with no intra-procedural anticoagulation for the FFR calculation with a saline bolus and drip used for placebo anticoagulation during the procedure to blind the operator | Procedure: FFR<br>* Fractional flow reserve tracings were calculated using a Volcano pressure wire intra-coronary system after ensuring proper calibration of the aortic pressure transducer and the guidewire, using 6 Fr-guide catheters. Before crossing the stenosis, baseline pressure was measured by the guide catheter and the pressure guidewire were equalized according to the manufacturer's specifications. After advancing the pressure sensor across the stenosis, coronary hyperemia was induced using intravenous adenosine (140μg/kg/min until a steady state was reached for at least 3 minutes). Fractional flow reserve was considered positive if it was less than 0.80.<br>* Other names: Fractional Flow Reserve;Drug: Aspirin<br>* All patients received a chewable aspirin of 325 mg at least 6 hours before the procedure<br>Drug: Clopidogrel<br>* All patient receiving clopidogrel, were loaded with 600 mg at least 6 hours before the procedure<br>|
| Active Comparator: Group 2<br>Received upstream aspirin and clopidogrel plus intra-procedural anticoagulation with bivalirudin for FFR calculation | Procedure: FFR<br>* Fractional flow reserve tracings were calculated using a Volcano pressure wire intra-coronary system after ensuring proper calibration of the aortic pressure transducer and the guidewire, using 6 Fr-guide catheters. Before crossing the stenosis, baseline pressure was measured by the guide catheter and the pressure guidewire were equalized according to the manufacturer's specifications. After advancing the pressure sensor across the stenosis, coronary hyperemia was induced using intravenous adenosine (140μg/kg/min until a steady state was reached for at least 3 minutes). Fractional flow reserve was considered positive if it was less than 0.80.<br>* Other names: Fractional Flow Reserve;Drug: Aspirin<br>* All patients received a chewable aspirin of 325 mg at least 6 hours before the procedure<br>Drug: Clopidogrel<br>* All patient receiving clopidogrel, were loaded with 600 mg at least 6 hours before the procedure<br>Drug: Bivalirudin<br>* Dosed based on the weight at 0.75 mg/kg I.V. bolus dose followed by a 1.75 mg/kg/hr I.V. infusion for the duration of the procedure<br>|
| Experimental: Group 3<br>Received only upstream single anti-platelet therapy with aspirin plus intra-procedural anticoagulation for the FFR calculation with bivalirudin | Procedure: FFR<br>* Fractional flow reserve tracings were calculated using a Volcano pressure wire intra-coronary system after ensuring proper calibration of the aortic pressure transducer and the guidewire, using 6 Fr-guide catheters. Before crossing the stenosis, baseline pressure was measured by the guide catheter and the pressure guidewire were equalized according to the manufacturer's specifications. After advancing the pressure sensor across the stenosis, coronary hyperemia was induced using intravenous adenosine (140μg/kg/min until a steady state was reached for at least 3 minutes). Fractional flow reserve was considered positive if it was less than 0.80.<br>* Other names: Fractional Flow Reserve;Drug: Aspirin<br>* All patients received a chewable aspirin of 325 mg at least 6 hours before the procedure<br>Drug: Bivalirudin<br>* Dosed based on the weight at 0.75 mg/kg I.V. bolus dose followed by a 1.75 mg/kg/hr I.V. infusion for the duration of the procedure<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thrombotic Complications |  | Hospital Stay and after 30 days post PCI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| TIMI (Thrombolysis in Myocardial Infarction) Major and Minor Bleeding Scores | Major: Intracranial bleeding, Clinically overt signs of hemorrhage associated with a drop in hemoglobin of ≥5 g/dL or a ≥15% absolute decrease in haematocrit or Fatal bleeding. Minor: Clinically overt (including imaging), resulting in hemoglobin drop of 3 to <5 g/dL or ≥10% decrease in haematocrit. No observed blood loss: ≥4 g/dL decrease in the haemoglobin concentration or ≥12% decrease in haematocrit Any overt sign of hemorrhage that meets one of the following criteria and does not meet criteria for a major or minor bleeding event, as defined above Requiring intervention | Hospital Stay and after 30 days post PCI | 
| Sub-clinical Ischemic Events Measured by Troponin Levels Post-procedure |  | 48 hours post procedure |