Atrial and Brain Natriuretic Peptide Secretion After Percutaneous Closure of the Left Atrial Appendage

Study Overview
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Brief Summary
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To date there are no data suggesting substantial effects of hormonal interaction after percutaneous closure of the left atrial appendage (LAA). Our hypothesis is that by excluding the LAA from blood flow physiologic stimuli for ANP and BNP produce may be impaired and consecutive release of the hormones may be reduced. Here, we present our experience of ANP and BNP secretion in the early postprocedural period after transcatheter closure of the LAA.

Official Title
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Interventional Study to Investigate the Effects of Percutaneous Closure of the Left Atrial Appendage on Atrial and Brain Natriuretic Peptide Secretion

Conditions
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Atrial Fibrillation, Stroke Prevention, Left Atrial Appendage

Intervention / Treatment
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* Device: WATCHMAN LAA system (Percutaneous left atrial appendage closure)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: non-valvular atrial fibrillation increased risk for thromboembolic complications (a minimum CHADS2Score of at least 2) Exclusion Criteria: Valvular-atrial fibrillation Low risk for thromboembolic complications CHADS-2-Score < 2

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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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: atrial and brain natriuretic peptide<br>Impact on atrial an brain natriuretic peptide secretion after percutaneous left atrial appendage closure | Device: WATCHMAN LAA system (Percutaneous left atrial appendage closure)<br>* The WATCHMAN LAA system (Altritech Inc., Plymouth, MN),Percutaneous occlusion systems have been developed as an alternative to anticoagulation for stroke prevention. Briefly, transseptal puncture is performed to gain access to the left atrial appendage (LAA). Thereafter LAA angiography is performed. After an optimal device size is chosen based on LAA measurements by fluoro and echocardiography the occluder is implanted into the orifice of the left atrial appendage under fluoroscopy and TEE-guidance. The size of the device is chosen to be 10% to 20% larger than diameter of the LAA ostium to have stable positioning of the device. Every procedure is performed under local anaesthesia. Heparin is given during implantation procedure to achieve an activated clotting time of at least 250.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline Plasma ANP and BNP levels after transcatheter closure of the left atrial appendage. | Venous blood samples are taken before the procedure, immediately after implantation of the LAA closure device and on the first morning after the procedure. The blood is drawn into plastic tubes containing aprotinin and ethylenediaminetetraacetic acid disodium and is promptly centrifuged. The plasma obtained is stored at -20°C until assayed. The plasma BNP and ANP concentrations are then determined with a commercially available enzyme immunoassay kit (ELISA Kit for Brain Natriuretic Peptide, Uscn Life Science Inc., Missouri City, USA and ANP ELISA Kit, Hölzel Diagnostika, Köln, Germany). | participants will be followed for the duration of hospital stay, an expected average of 48 hours |