Whenever the blood flowing through an artery or vein is obstructed, a blood clot is formed. This blood clot is known as a thrombus, and it often leads to blockage of blood vessels at the site. The blood clot, or maybe a portion of it, may break off and move through the bloodstream as an embolus, which will get stuck at a narrow point. A blood vessel can also get blocked if foreign matter, like bacteria, air, or fat, is transported into the bloodstream. There are some clots that can become infected, with life-threatening blood clots being reported mostly in animals that have underlying diseases that inhibit the blood’s clotting. Without adequate treatment or proper management, the results could be excessive bleeding. A life-threatening situation may develop, where tiny blood clots flow through the bloodstream, obstructing the blood vessels and using up valuable platelets and clotting factors.
The development of a thrombus can take place in both big and small arteries and veins, resulting in an insufficient delivery of blood to the nearby tissues, while also affecting the heart and central nervous system. Additionally, pus-filled clots can spread bacterial and localized infection.
An aneurysm can be defined as an enlargement of a blood vessel due to weakening of the central layer of the blood vessel. Interference of the internal layer of a blood vessel associated with an aneurysm can lead to creation of a blood clot, which ultimately causes blockage of the same blood vessel by the clot.
Symptoms and Diagnosis
One main symptom of pulmonary embolism in dogs or a blood clot in the lungs is an unexpected development of breathing problems, with dogs coughing up blood or bloody mucous. Clots in the heart that are infected are usually linked to infective endocarditis, an inflammation of the membranes that line the cardiac cavity. Non-infected clots in the heart are commonly linked to cardiac muscle disease. If the urine is bloody or there is any abdominal pain, then this could be indicative of blocked vessels in the urinary or genital systems. It is important to note that similar symptoms to these can also be due to blockage of blood vessels to the abdominal organs, although in this case the symptoms may be supplemented by vomiting and an inability to control the bladder and bowels.
Blood clots that develop in the pulmonary artery usually cause breathing problems and an elevated respiratory rate. Dogs that suffer from this condition usually appear healthy until they develop an unexpected onset of breathing distress. Chest x-rays may help to detect and determine changes like an overgrown main pulmonary artery and right heart, inadequate quantities of blood reaching the affected area, a build-up of fluid in the chest cavity, and bleeding within the lungs. Nonetheless, more tests should be conducted in order to diagnosis the core diseases.
Heartworm disease is another factor that may cause blood clots in the arteries of the lungs, with the lining of the heart cavity also being susceptible to bacterial infection, pneumonia and subsequent blood clots in the lungs and pneumonia. Other conditions related to blood clots in the lungs consist of diabetes mellitus, kidney disease, hyperadrenocorticis (increased adrenal gland hormones), immune-mediated haemolytic anaemia, and cancer.
Endocarditis that causes pneumonia is usually treated using long-term antibiotics, which is a treatment regimen that could last several weeks. In some cases, anti-inflammatory drugs may be required in order to reduce fever. However, the recovery rates are not as promising.
Management of blood clots in the veins is typically restricted to supportive care, such as hydrotherapy of available veins, anti-inflammatory medicine, and oral or injected antibiotics to contain secondary infection. Though treatment of thrombosis of the large veins that empty into the right atrium is available, it usually doesn’t produce very positive outcomes.