Circ-Calm4 is a specific circular RNA that modulates pyroptosis-related signaling pathways and targets in the PASMCs, thereby regulating PAH; moreover, inhibition of circ-Calm4 significantly reduced the levels of pyroptosis-related proteins such as NLRP3, caspase-1, IL-1β, and IL-18 in the PASMCs 65. Here, IL18 is linked to pulmonary arterial hypertension.