Tolafentrine is a dual-selective phosphodiesterase 3/4 (PDE3/4) inhibitor that has demonstrated significant acute and chronic effects in a rat model of pulmonary hypertension induced by monocrotaline. Studies indicate that prolonged administration notably alleviates hemodynamic and gas exchange abnormalities caused by monocrotaline, reduces right ventricular hypertrophy, and normalizes changes in pulmonary vascular remodeling.