CBS.com; CBS All Access; CBS News; CBSN; Watching Live TV. All Access Live TV; TV Provider
Thick blood may also be caused by the presence of harmful pathogens such as fungi, viruses, bacteria, and parasites. These pathogens can actually activate a coagulation response in the body as a way to avoid being attacked by the bodyâs immune system.
Causes of a Thickened Vessel. Aneurysm. An aneurysm is the bulging of a portion of a blood vessel. It is an abnormal dilatation, like a balloon, and may affect an intact vessel wall (true aneurysm) or diseased wall (false aneurysm).It is not an actual thickening of the blood vessel wall but is rather a protrusion of the wall. Dissection.