Study to Investigate the Effect of Heart Rate Reduction With Ivabradine on Vascular Elastic Properties and Endothelial Function in Patients With Stable Coronary Heart Disease

Study Overview
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Brief Summary
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This study investigates whether chronic heart rate reduction with ivabradine (Procoralan®, Servier, France) affects aortic compliance and endothelial function in patients with chronic stable coronary artery disease.

Detailed Description
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Experimental and clinical data suggest that sustained elevation of heart rate contributes to the pathogenesis of vascular disease (1, 2). In animal studies accelerated heart rate is associated with signalling events leading to vascular oxidative stress, endothelial dysfunction and acceleration of atherogenesis (3). The underlying mechanisms are only partially understood and appear to correlate with mechanic properties such as reduction of vascular compliance. Heart rate reduction by I(f)-channel inhibition with ivabradine (Procoralan®, Servier, France) attenuates oxidative stress, improves endothelial function and reduces the formation of atherosclerotic plaques in mice models of lipid-induced atherosclerosis (1, 4). Aortic stiffness is a consequence of arterial aging and vascular risk factors and determinates cardiovascular mortality (5). Heart rate depending repetitive pulsations appear to induce fatigue and fracture of elastin lamellae of central arteries. As a result the vessel stiffens and pulse wave reflections return earlier to the heart. In consequence aortic pressure rises and pulsations of flow extend further into smaller vessels of organs (notably the brain and kidney). Stiffening leads to increased left ventricular (LV) load with hypertrophy, decreased capacity for myocardial perfusion, and increased hemodynamic stresses on small arterial vessels. Several experimental investigations revealed an interaction between heart rate and vascular compliance demonstrating a positive association between increased heart rate and arterial stiffness (6). Recent experimental data suggest that heart rate reduction by ivabradine (Procoralan®, Servier, France) significantly improves aortic distensibility in cholesterol fed ApoE -/- mice measured by MRI technique (7). While a benefit of pharmacological heart rate reduction on vascular outcomes was observed in animal studies, prospective clinical data are limited and evidence determining whether chronic modulation of heart rate can improve vascular function and compliance in patients with chronic stable coronary artery disease is needed.

Official Title
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A Randomised, Placebo Controlled, Double Blind, Cross-over, Single Center Clinical Study to Investigate the Effect of Heart Rate Reduction With Ivabradine on Vascular Elastic Properties and Endothelial Function in Patients With Stable Coronary Heart Disease

Conditions
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Coronary Artery Disease, Coronary Arteriosclerosis

Intervention / Treatment
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* Drug: Ivabradine
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years old Resting heart rate ≥ 70 bpm Sinus rhythm Chronic stable coronary artery disease (CAD) Coronary artery disease proven by coronary angiography Written informed consent to participate in the study Exclusion Criteria: Acute coronary syndrome CAD treated best by surgical coronary bypass Stroke/TIA Resting heart rate < 70 bpm Indwelling pacemaker or AICD Severe valvular heart disease Any other rhythm than sinus Sick-Sinus-Syndrome, SA nodal block, >2nd degree atrio-ventricular block Untreated arterial hypertension Arterial hypotension (<90/50mmHg) Severe hepatic failure Heart failure (NYHA class III - IV) Patient already treated with study drug Symptomatic PAD Known diabetes mellitus Pre-menopausal women Hypersensitivity against ivabradine or adjuvants Coexisting drug treatment with Cytochrom P450 3A4-inhibitors

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Ivabradine<br>Drug: Ivabradine bid administration of 7.5mg ivabradine Other Name: Procoralan, I(f)-inhibitor | Drug: Ivabradine<br>* Please see description of Intervention Arm<br>* Other names: Procoralan;|
| Placebo Comparator: Placebo<br>Drug: Placebo bid placebo Other Name: Placebo control | Drug: Placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Aortic distensibility (MRI), pulse wave velocity (SphygmoCor®), flow-mediated dilatation (A. brachialis) |  | Decembre 2014 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Biomarkers (inflammation, oxidative stress) |  | Decembre 2014 |