Related Experiment Video

Updated: Sep 23, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
13:08

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay

Published on: September 9, 2012

Procoagulant and anticoagulant factor abnormalities following the Fontan procedure: increased factor VIII may

Kirsten C Odegard1, Francis X McGowan, David Zurakowski

  • 1Department of Anesthesia, Children's Hospital, Boston, MA 02115, USA. kirsten.odegard@tch.harvard.edu

The Journal of Thoracic and Cardiovascular Surgery
|June 28, 2003
PubMed

Insights

Children after the Fontan operation show lower levels of key coagulation factors. Elevated factor VIII in some patients warrants further investigation for thrombosis risk and potential anticoagulation therapy.

Area of Science:

  • Pediatric Cardiology
  • Hematology
  • Coagulation Science

Background:

  • The Fontan operation is a palliative procedure for complex congenital heart disease.
  • Coagulation abnormalities are a known complication in Fontan patients.
  • Hemodynamic changes post-Fontan may influence coagulation factor levels.

Purpose of the Study:

  • To prospectively evaluate coagulation factor abnormalities in children post-Fontan operation.
  • To assess the relationship between hemodynamic variables and coagulation status.
  • To identify potential predictors of coagulation abnormalities in this population.

Main Methods:

  • Assayed coagulation factors in 20 children post-Fontan and 24 age-matched controls.
  • Measured concentrations of multiple coagulation factors, inhibitors, and liver enzymes.
  • Evaluated demographic, hemodynamic, and time-related variables as predictors.

Main Results:

  • Fontan patients exhibited significantly lower levels of protein C, factors II, V, VII, X, plasminogen, and ATIII compared to controls.
  • Factor VIII was elevated in 35% of Fontan patients, with two experiencing thromboembolic events.
  • Higher superior vena cava pressure predicted elevated factor VIII, but no other hemodynamic factors predicted coagulation abnormalities.

Conclusions:

  • Procoagulant and anticoagulant factor levels are generally reduced in Fontan survivors, irrespective of Fontan-specific hemodynamics.
  • Elevated factor VIII levels in Fontan patients require further study as a potential cause of thrombosis.
  • Identifying patients with elevated factor VIII may guide decisions regarding anticoagulation therapy.
Abstract

Related Concept Videos

Anticoagulant Drugs: Low-Molecular-Weight Heparins01:30

Anticoagulant Drugs: Low-Molecular-Weight Heparins

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...
Venous Thrombosis III: Interprofessional Care01:29

Venous Thrombosis III: Interprofessional Care

Venous thrombosis requires effective prevention and treatment strategies to improve patient outcomes and reduce potential complications.Prevention StrategiesHealthcare providers must prioritize preventing venous thromboembolism (VTE) for all adult patients upon admission. Interventions depend on bleeding and thrombosis risk, medical history, current medications, diagnoses, planned procedures, and patient preferences. Patients on bed rest should change positions every two hours and, if not...
Extrinsic and Intrinsic Pathways of Hemostasis01:20

Extrinsic and Intrinsic Pathways of Hemostasis

Blood clotting or coagulation involves extrinsic and intrinsic pathways, which ultimately merge into the common pathway, forming a fibrin clot.
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which forms a...
Disorders of Hemostasis01:24

Disorders of Hemostasis

Hemostasis, the process that stops bleeding after a blood vessel injury, is crucial for maintaining the integrity of the circulatory system. However, disorders of hemostasis can disrupt this delicate balance, leading to either excessive clotting or bleeding. These disorders can be broadly classified into thromboembolic disorders and bleeding disorders.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Venous Thrombosis I: Introduction01:30

Venous Thrombosis I: Introduction

Venous thrombosis, the most common disorder of the veins, involves the formation of a thrombus or blood clot associated with vein inflammation. It can be classified as either superficial vein thrombosis or deep vein thrombosis.Superficial Vein Thrombosis: This involves the formation of a thrombus in a superficial vein, usually the greater or lesser saphenous vein. Though less severe than deep vein thrombosis (DVT), SVT can lead to complications if untreated.Deep Vein Thrombosis (DVT): This...
Clot Retraction and Fibrinolysis01:16

Clot Retraction and Fibrinolysis

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.