Cinaciguat, a soluble guanylyl cyclase (sGC) activator, could activate heme-deficient sGC to increase intracellular cyclic guanosine monophosphate (cGMP) for further biological effects and is currently used in patients with pulmonary hypertension (Evgenov et al., 2006). Here, SGCB is linked to pulmonary arterial hypertension.