What is pulmonary hypertension (PAH)?

By:  Risa Roland, DVM, DACVIM (Cardiology)

This term implies that there is high blood pressure in the lungs.  PAH occurs secondary to many other diseases in the body.  These diseases include, but are not limited to, heart disease, lung disease, endocrine diseases, kidney disease, heartworm disease and cancer.

If there is severe PAH present, it makes it difficult for the right-side of the heart to pump to the lungs normally.  This can make it difficult to get the appropriate amount of oxygen from the lungs needed by the body.  This can then lead to weakness, lethargy, fainting, breathing difficulties or a fast breathing rate and, in rare cases, can lead to passing away suddenly.  Since PAH makes it difficult for the right side of the heart to pump blood to the lungs well, it can also lead to right-sided congestive heart failure (fluid from the blood is backing up into the abdomen).

Signs of PAH include fainting, weakness, exercise intolerance, abdominal distension and blue gums.  If you notice any of these signs in your animal, you should contact your veterinarian or an emergency clinic as your pet may be experiencing PAH.