Offset of Ticagrelor's Effect on Endothelial Function as Assessed With Peripheral Arterial Tonometry (EndoPAT Assay)

Study Overview
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Brief Summary
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Ticagrelor administration, whose molecule resembles to adenosine, led to reduction in overall mortality and thrombotic cardiovascular (CV) events when directly compared to clopidogrel in the PLATO trial, implicating possible pleiotropic actions for the drug. It has been shown that ticagrelor increases adenosine concentration, by interfering with its red blood cells' uptake and by inducing the release of ATP which is then converted to adenosine. Recent studies in healthy volunteers and patients with coronary artery disease (CAD) have shown that ticagrelor increases the coronary blood flow in response to intravenous adenosine administration. Ticagrelor administration, in comparison with other P2Y12 inhibitors, may influence the endothelial function, as assessed by the Peripheral Arterial Tonometry method (EndoPAT 2000 system (Itamar Medical, Caesarea, Israel), which is a method for evaluating endothelial dysfunction and has been found to positively correlate with flow mediated dilatation (FMD). This is a prospective, observational study, which will be conducted in patients with coronary artery disease subjected to percutaneous coronary intervention (PCI) under ticagrelor maintenance dose (MD) 90mg x 2, who are about to stop treatment, due to completion of 1 year antiplatelet therapy. Eligible patients will be subjected to peripheral arterial tonometry at Day 0 (immediately after receiving the last pill of ticagrelor) and at day 2 and day 5 post study drug discontinuation. Peripheral blood sample will be taken from the patients at Day 0 for genotype analysis.

Official Title
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Offset of Ticagrelor's Effect on Endothelial Function as Assessed With Peripheral Arterial Tonometry (EndoPAT Assay)

Conditions
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Coronary Artery Disease, Endothelial Function

Intervention / Treatment
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* Device: Peripheral arterial tonometry (EndoPAT)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age above 18-80 years old Patients with Coronary Artery Disease receiving ticagrelor maintenance dose (MD) 90mg x 2 and are about to discontinue the treatment due to the completion of 1 year of dual antiplatelet therapy. Patients giving written Informed Consent. Exclusion Criteria: Acute Coronary Syndrome Foreseeable need for anticoagulant treatment within the next 5 days Severe non-regulated with theophylline/aminophylline administration chronic obstructive pulmonary disease Creatinine Clearance <30ml/min/1.73mm2 HbA1c > 10mg/dl

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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 |
| --- | --- |
| Ticagrelor discontinuation<br> | Device: Peripheral arterial tonometry (EndoPAT)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reactive Hyperemia Index (RHI) on Day 0 and on Day 5 | Reactive Hyperemia Index (RHI) on Day 0 will be compared to RHI on Day 5 | 5 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reactive Hyperemia Index (RHI) on Day 0 and on Day 2 | Reactive Hyperemia Index (RHI) on Day 0 will be compared to RHI on Day 2 | 2 days | 
| Reactive Hyperemia Index (RHI) on Day 2 and on Day 5 | Reactive Hyperemia Index (RHI) on Day 2 will be compared to RHI on Day 5 | 3 days | 
| The percentage of patients with RHI<1.67 on Day 0 and on Day 5 |  | 5 days | 
| The percentage of the patients with RHI<1.67 on Day 0 and on Day 2 |  | 2 days | 
| The percentage of the patients with RHI<1.67 on Day 2 and on Day 5 |  | 3 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ticagrelor, endothelial function, peripheral arterial tonometry