Here we describe a woman being treated with the combination of a VEGF receptor (VEGFR) inhibitor and a programmed death-ligand 1 (PD-L1) inhibitor who developed pulmonary hypertension and right heart failure and was subsequently found to have PTTM with features of pulmonary veno-occlusive disease (PVOD). This evidence concerns the gene KDR and pulmonary arterial hypertension.