New hope for chest pain without blocked arteries? early trial tests macitentan

This study tests a drug called macitentan in 40 adults with chest pain that isn't caused by blocked arteries (non-obstructive angina). The goal is to see if the drug improves blood flow in the tiny heart vessels and reduces chest pain. Participants will take macitentan for 4 weeks and have heart function tests and blood samples taken to understand how the drug works.