A research team with the Faculty of Medicine & Dentistry at the University of Alberta reported findings that significantly improve understanding of how widely used drugs in Pulmonary Arterial Hypertension (PAH) affect the heart health of treated patients.
The research shows that medications often prescribed for PAH could block the function of an important hormone in the heart, decreasing the strength of contraction of the right heart chambers, a potentially important and yet unrecognized adverse effect.
PAH is a disease that affects the blood vessels of the lungs, causing a progressive narrowing and restriction of the blood flow through the lungs. This narrowing puts a significant strain in the right chamber (right ventricle) of the heart that pushes the blood through the lungs. Eventually the right ventricle fails, causing heart failure and death.
One of the causes of the narrowing of the lung blood vessels is the increased levels of endothelin in the lungs, a hormone that constricts blood vessels throughout the body. Commonly used and very expensive drugs that block the actions of endothelin, which are called endothelin receptor antagonists, or ERAs, are now used throughout the world to treat PAH patients. However, the effects of these drugs in the right ventricle had not previously been studied, until now.