Which medication is NOT recommended in acute RV failure caused by PAH?

In the context of acute right ventricular (RV) failure due to pulmonary arterial hypertension (PAH), medications that have rapid vasodilatory effects and can improve hemodynamics are generally preferred. Treprostinil, epoprostenol, and iloprost are all prostacyclin analogs that induce pulmonary vasodilation and are known to provide acute relief in the setting of right ventricular failure. These medications can improve blood flow and reduce the pressure load on the right ventricle.

Bosentan, on the other hand, is an endothelin receptor antagonist that primarily functions by inducing long-term improvements in exercise capacity and functional class in patients with PAH. However, it does not demonstrate the rapid onset of action necessary for the acute management of right ventricular failure. Bosentan has a delayed effect and may take weeks for optimal results, making it unsuitable for immediate treatment in acute situations like RV failure, where quick intervention is crucial.

Overall, the pharmacokinetic properties and mechanisms of action of bosentan render it inappropriate for acute management scenarios, distinguishing it from the more urgently acting therapies in this setting.