Novel indications for phosphodiesterase type 5 inhibitors]

Phosphodiesterase type 5 (PDE5) induces the breakdown of cyclic guanosine monophosphate (cGMP) in smooth muscle cells. Hence, PDE5 inhibitors promote vasodilative effects by enhancing intracellular cGMP levels. Three PDE5 inhibitors, sildenafil, vardenafil, and tadalafil, have been approved for the treatment of "erectile dysfunction" (ED). All three show an excellent effectiveness regarding ED therapy, but differ from one another regarding their pharmacokinetic properties. Recent experimental studies and clinical trials indicate that PDE5 inhibitors are also effective in the treatment of various other diseases such as pulmonary arterial hypertension (PAH), Raynaud's disease, gastrointestinal disorders, and stroke, and furthermore exert cardioprotective effects. This review describes the cardiovascular safety of PDE5 inhibitors and provides an overview of the current literature regarding potential novel indications.