The key difference between thrombus and postmortem clot is that thrombus is an aggregation of platelets, fibrins, and red blood cells and is dry, granular, and firmly attached to the endothelial wall. Meanwhile, a postmortem clot is an aggregation made primarily from fibrin, which is gelatinous, rubbery, dark red, and weakly attached to the endothelial wall.
Thrombi and postmortem clots are two types of aggregations related to blood vessels. Thrombus occurs in living animals, while postmortem clots occur after death. Thrombus primarily consists of platelets, while postmortem clot primarily consists of fibrins. Moreover, the presence and absence of lines of Zahn is a distinguishable characteristic between thrombus and postmortem clot. These lines are shown only in thrombi formed before death.
CONTENTS
1. Overview and Key Difference
2. What is Thrombus
3. What is Postmortem Clot
4. Similarities – Thrombus and Postmortem Clot
5. Thrombus vs Postmortem Clot in Tabular Form
6. Summary – Thrombus vs Postmortem Clot
What is a Thrombus?
A thrombus is an aggregation of platelets, fibrin, and red blood cells inside a blood vessel blocking the normal blood flow. Therefore, it is a blood clot that acts as a plug. Thrombosis is the process that forms thrombi in blood vessels. A thrombus can form as a healthy response to an injury in order to stop further bleeding. If a thrombus blocks a major blood vessel transporting blood to an essential organ, it will be life-threatening due to the death of the tissue or organ. Normally thrombi are firmly attached to the endothelial wall where they form. But some thrombi flow freely and dislodge. These free-floating thrombi are known as emboli. They are potentially fatal. Based on the site or location they have lodged, emboli can cause significant conditions like strokes, heart attacks, and even death of the person. In that case, anticoagulants can be used to reduce the risk of blood clot formation. Drugs that promote thrombolysis can be used for breaking formed blood clots.
There are two types of thrombi; they are arterial or white thrombi and venous or red thrombi. Arterial thrombi are formed in an artery, while venous thrombi are formed in a vein. The presence of lines of Zahn is characteristic of thrombi. They are microscopic altering layers of platelets, fibrin, and red blood cells. The presence of these lines indicates that there was a rapid blood flow before the death. There are several tests to diagnose thrombi. Some of them are D-dimer tests, duplex ultrasounds, MRI, CT scans, venography, and VQ scan.
What is a Postmortem Clot?
Post-mortem clots are blood clots that primarily contain fibrins. They usually form shortly after the death of an animal. Unlike in thrombi, lines of Zahn are absent in postmortem clots. Postmortem clots do not adhere to the endothelium. Their surface is smooth and glistering. They are red-cloured and elastic in nature. Postmortem clots mainly occur in cardiac chambers after death. There are two portions of the postmortem clot; they are the dependent portion where red blood cells are settled, and the upper portion, which is a yellow chicken fat upper portion.
What are the Similarities Between Thrombus and Postmortem Clot?
- Both thrombi and postmortem clots are blood clots formed due to aggregation of blood constituents.
- They contain red blood cells.
What is the Difference Between Thrombus and Postmortem Clot?
A thrombus is a blood clot formed in a blood vessel of a living animal, while a postmortem clot is a mass of fibrins and red blood cells formed in the cardiac chambers of a dead animal. Thus, this is the key difference between thrombus and postmortem clot. Besides, the thrombus has lines of Zahn, while the postmortem clot doesn’t have lines of Zahn. So, this is also a difference between thrombus and postmortem clot. Moreover, thrombi are firmly attached to the endothelial wall of the site of origin, while postmortem clots are not attached to the endothelial wall.
The below infographic presents the differences between thrombus and postmortem clot in tabular form for side-by-side comparison.
Summary – Thrombus vs Postmortem Clot
Thrombi and postmortem clots are two types of blood clots. A thrombus is mainly an aggregation of platelets, fibrins, and red blood cells that form within a blood vessel in a living animal. A Postmortem clot is an aggregation of fibrins formed at cardiac chambers shortly after the death of an animal. A thrombus can be distinguished from a postmortem clot by the presence of lines of Zahn and the firm attachment to the endothelial wall. So, this is the summary of the difference between thrombus and postmortem clot.
Reference:
1. “What Is a Thrombus? Causes and Types.” Medical News Today, MediLexicon International.
2. “Thrombi, Post-Mortem Clots and Agonal Thrombi: How to Tell the …” – AGMV.
Image Courtesy:
1. “Blood clot diagram” By en:User:Persian Poet Gal – (CC BY-SA 3.0) via Commons Wikimedia