Pulmonary Hypertension ( PH ) in Beef Cattle : Complicated Threat to Health and Productivity in Multiple Beef Industry Segments

Pulmonary Hypertension (PH): Pulmonary arteries carry venous blood from the right heart chambers to the lungs so that the blood can be oxygenated. Blood returns through the pulmonary veins to the left chambers of the heart and then pumped to the rest of the body. Pulmonary arterial pressure (PAP) is abnormally high when an animal experiences PH. The right side of the heart responds to the increased work from forcing blood against high PAP. This causes excessive muscle contraction, stretching of muscle fibers, and increased size of the right-side of the heart. When the heart chambers exceed capacity, and its walls thicken, the heart fails and the animal dies. These mortality rates are typically very low even though cattle often experience PH. The consequences of PH on overall health and performance is a growing concern in the beef industry.