Related Experiment Video
Updated: Feb 25, 2026
06:47
Microfluidics in Assessing Platelet Function
Published on: November 8, 2024
1.7K
Platelet function and microparticle levels in atrial fibrillation: Changes during the acute episode
Line Pourtau1, Jean Marc Sellal2, Romaric Lacroix3
1IHU Liryc, Electrophysiology and Heart Modeling Institute, fondation Bordeaux Université, 33600, Pessac, France; Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, U1045, 33000 Bordeaux, France; INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, U1045, 33000 Bordeaux, France.
International Journal of Cardiology
|July 28, 2017
Summary
Atrial fibrillation (AF) patients show reduced platelet aggregation and microparticle (MP) activity. Acute AF episodes decrease MP tissue factor activity, potentially increasing clot formation and thrombin generation.
Area of Science:
- Cardiovascular Medicine
- Hematology
- Thrombosis Research
Background:
- Atrial fibrillation (AF) is associated with a significant risk of thrombosis.
- The roles of platelets and microparticles (MPs) in AF-related hemostasis and thrombosis are not fully understood.
Purpose of the Study:
- To characterize platelet function and MP procoagulant/fibrinolytic activity in AF patients.
- To investigate the impact of acute AF episodes on these parameters.
Main Methods:
- Blood samples from paroxysmal and persistent AF patients undergoing ablation were analyzed.
- Platelet aggregation and surface receptor expression were assessed.
- Functional assays determined MP-associated procoagulant and fibrinolytic activity before and after induced AF.
Main Results:
- AF patients exhibited reduced platelet aggregation response to TRAP (thrombin receptor activator peptide).
- No differences in platelet receptor expression were observed.
- Acute AF induction led to improved platelet response and decreased left atrial MP tissue factor-dependent procoagulant activity.
Conclusions:
- Acute AF episodes may decrease MP tissue factor activity, potentially promoting local coagulation and thrombin production.
- Reduced platelet aggregation in AF might stem from PAR-1 desensitization, with induced AF episodes suggesting PAR-1 re-sensitization.
Keywords:
Atrial fibrillationMicroparticle procoagulant activityMicroparticles fibrinolytic activityPlateletsThrombin receptorTissue factorMore Related Videos
Related Concept Videos
01:18Structure and Function of Platelets
4.0K
The cell fragments known as platelets are disc-shaped, with an average diameter of about 3 μm and a thickness of roughly 1 μm. They play a crucial role in the body's vascular clotting system, which also involves plasma proteins, blood cells, and blood vessel tissues.
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000...
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000...
4.0K
01:22Formation of the Platelet Plug
10.0K
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
10.0K
01:16Clot Retraction and Fibrinolysis
9.5K
After a fibrin clot is formed, the next step is clot retraction, a vital process facilitated by platelet contractile proteins, such as actin and myosin. These proteins pull the fibrin strands closer together and condense the clot. This action reduces the size of the clot, creating a smaller, denser structure that effectively seals off the damaged vessel. Clot retraction consolidates the clot and helps with wound healing by bringing the edges of the damaged blood vessel closer together.
9.5K
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
2.1K
Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
2.1K
01:05Introduction to Hemostasis
15.2K
Hemostasis is a complex physiological process that prevents excessive bleeding when a blood vessel is injured. It's crucial for maintaining the integrity of the circulatory system, as it ensures that our blood remains fluid while still within the vascular network and yet clots to prevent blood loss upon vessel injury.
The three phases of hemostasis involve many clotting factors present in plasma and several substances released by platelets and injured tissue cells. It is a fast, localized,...
The three phases of hemostasis involve many clotting factors present in plasma and several substances released by platelets and injured tissue cells. It is a fast, localized,...
15.2K