Clinical Research Directory

Atrial Fibrillation TRIal of Left Atrial Appendage Closure Using Seralene Hemostatic Suture

Atrial fibrillation is a common heart rhythm disorder that increases the risk of stroke. In patients with atrial fibrillation, blood clots most often form in a small structure of the heart called the left atrial appendage. If a blood clot travels from the heart to the brain, it can cause a stroke. Blood-thinning medications are commonly prescribed to reduce the risk of stroke in patients with atrial fibrillation. However, some patients cannot take these medications long-term because of bleeding risk, side effects, or other medical reasons. Closing the left atrial appendage is an alternative approach to reduce the risk of stroke by preventing blood from collecting in this area. When patients undergo cardiac surgery for another indication, closure of the left atrial appendage can be performed during the same operation. This study is designed to evaluate the safety and effectiveness of surgical closure of the left atrial appendage using a device called AtriLASH during cardiac surgery. AtriLASH is a surgical suture-based device intended to close the left atrial appendage. The study will assess whether the left atrial appendage can be safely and effectively closed using this method in patients with atrial fibrillation undergoing cardiac surgery. The information obtained from this study may help determine whether this approach can reduce the risk of stroke and potentially decrease the need for long-term use of blood-thinning medications in selected patients.

Thrombolysis in Factor Xa-inhibitors Trial

This study looks at whether stroke patients who take FXa inhibitors (a type of blood thinner) can safely receive clot-busting treatment (IVT). IVT is a common emergency treatment for stroke, but current guidelines say it should not be given to people who have taken FXa inhibitors in the last 48 hours. This is because doctors worry that IVT might cause dangerous bleeding in the brain. However, new research suggests that IVT might be safe for these patients. Some studies even show that stroke patients on FXa inhibitors who receive IVT do not have a higher risk of brain bleeding than other stroke patients. But because these studies were not designed as full medical trials, doctors still avoid IVT for this group. The SIFT trial will compare two groups of stroke patients who take FXa inhibitors: One group will receive IVT to see if it helps them recover better. One group will not receive IVT, which is the current standard. Doctors will check if IVT helps with recovery and if it causes any serious bleeding. If IVT is found to be safe and effective, this study could change stroke treatment guidelines and help more patients get life-saving care. Right now, some guidelines say that stroke patients on FXa inhibitors should have a blood test before getting IVT, to measure how much of the drug is in their system. But these tests are not available in most hospitals, and waiting for results could delay important treatment. The SIFT trial will not require this test before giving IVT. More and more people use FXa inhibitors to prevent strokes, but right now, they are being denied IVT based on old rules. If this study proves that IVT is safe for them, it could help doctors give better care to thousands of stroke patients.

Heat Shock Protein 47 in Thrombosis

The goal of this observational study is to learn if the novel biomarker Heat shock protein 47 (HSP47) can be used as a prognostic marker for vascular disease in people with acute venous thromboembolism (VTE), myocardial infarction (AMI) or ischaemic stroke compared to healthy volunteers. The main questions it aims to answer are: 1. Are platelet levels of HSP47 higher in patients with acute VTE, AMI or stroke, compared to healthy volunteers. 2. Does platelet levels of HSP47 remain elevated in patients with acute thrombotic events compared to healthy volunteers at 3 and 12-months of follow-up. 3. Are platelet levels of HSP47 postively associated with platelet function and negatively associated with fibrinolytic capacity in patients with an acute thrombotic event. Participants with VTE, AMI or stroke will be giving a blood sample at diagnosis and again after 3 and 12 months of follow-up. Healthy volunteers will be giving a blood sample once.

DOAC or VKA in Patients With AF and Stroke While on DOAC - a Pilot Trial

People with atrial fibrillation who have a stroke while receiving a DOAC are at increased risk of experiencing another stroke. Physicians do not know the best medication to prevent another stroke in this group of people. Options include continuing the same DOAC, switching to another DOAC or switching to warfarin. The investigators of the SWITCH-AF trial are trying to find out whether switching to warfarin or continuing a DOAC is better for preventing stroke. The purpose of this study, called a pilot study, is to test the study plan and to find out whether enough participants will join a larger study that answers the question. A pilot study involves a small number of participants and it is not expected to tell us which treatment is better.

Stroke Risk Assessment and Markers of Blood Clotting in Patients With Newly Diagnosed Non-valvular Atrial Fibrillation (NVAF), Who Have Not Received Oral Anticoagulation Therapy (OAC-therapy) Prior to Inclusion

Background: Atrial fibrillation (AF) is the most common heart rhythm disorder worldwide. Globally, there are 37.5 million people with AF. AF increases the risk of death, heart failure, and stroke, which severely affect patients and also lead to high healthcare costs. Around 25% of all strokes are caused by AF, and patients with stroke due to AF tend to have a higher risk of death and more disability compared to stroke patients without AF. Stroke prevention is, therefore, an important part of AF treatment, in which blood thinning medication has an important role. However, blood thinners increase the risk of bleeding. Therefore, it is important to divide patients with AF into different risk groups, known as risk assessment, to figure out who will benefit the most from blood thinners. To be able to divide patients into different risk groups, various stroke risk assessment tools have been developed, such as the CHA2DS2-VASc score and the ABC-stroke score. The most commonly used tool is the CHA2DS2-VASc score, including only clinical risk factors, such as high blood pressure, diabetes, etc. The ABC-stroke score, which includes blood markers of heart function, has been proven to outperform the CHA2DS2-VASc score in terms of predicting stroke in AF patients. However, the CHA2DS2-VASc score remains the primary stroke risk assessment tool for AF patients in current guidelines. After looking at the different risk factors, patients are divided into three groups: low, intermediate, and high risk. High-risk patients must take blood-thinning medication for life, while low-risk patients do not need it. In the medium-risk group, it remains uncertain whether blood thinners should be given or not. Despite the broad use of the CHA2DS2-VASc score, the score itself has limitations. The score does not include important factors, such as the duration of AF, the size and function of the upper heart chambers, as well as the stiffness of the heart, and markers of blood clotting, which are proven markers of a state that inceases the risk of blood clots. Furthermore, the CHA2DS2-VASc score does not consider whether heart failure, high blood pressure, and diabetes are well-controlled or not, which could lead to overuse of blood thinners. Therefore, the current risk assessment tools for patients with AF are incomplete, and improvements are needed. Overall hypothesis: Overall hypothesis is that the different components of the CHA2DS2-VASc score and ABC-stroke score affect blood clotting markers differently, depending on whether conditions like heart failure, high blood pressure, and diabetes (modifiable risk factors) are well-controlled or not. Investigators also expect to see differences in blood clotting markers across different stroke risk groups (low, intermediate, and high risk, based on the CHA2DS2-VASc score and ABC-stroke score) in AF patients who have not yet started blood thinning medication. Furthermore, investigators believe that the duration of AF, the size/function of the upper heart chambers, as well as the stiffness of the heart, can reflect an increased risk of blood clots in AF patients. Overall goal of the study: The overall goal of the study is to help improve the current tools used to assess the risk of stroke in patients with newly diagnosed AF. This will be done by adding more factors to the current risk assessment tools that reflect an increased risk of stroke, such as the burden of AF, the size/function of the heart's upper chambers, as well as the stiffness of the heart, and using biomarkers that show the blood's ability to clot as a substitute measure for stroke risk. Methods: The study is a cross-sectional, single-center observational study and will take place at Esbjerg Hospital - University Hospital of Southern Denmark, involving collaboration between the Unit for Thrombosis Research, Department of Clinical Diagnostics and the Department of Cardiology. The study population will consist of 150 participants with newly diagnosed AF. The participants must not be taking a specific type of blood thinner, called anticoagulant therapy (OAC-therapy), before being included in the study. The participants will be recruited with the help of the general practitioners (GPs). The general practitioners will be thoroughly informed about the study and the importance of waiting to start OAC-therapy until the participants have been seen at the cardiology outpatient clinic. The participants will be scheduled for a blood test, an ultrasound of the heart (echocardiography), and a 7-day heart rhythm monitoring within 4 days after their first meeting with the GP.