Phosphodiesterase type 5 inhibitors improve endothelial function and may benefit cardiovascular conditions.

The effects of phosphodiesterase type 5 inhibitors on vasodilation mediated via nitric oxide-cyclic guanosine monophosphate are well described. Less is known about other mechanisms through which phosphodiesterase type 5 inhibitors benefit endothelial function, including normalization of serum biomarkers, increased levels of endothelial progenitor cells, ischemia-reperfusion protection mechanisms, and other actions specific to patients with diabetes. These various mechanisms are reviewed. Their impact on several cardiovascular diseases, including erectile dysfunction, pulmonary hypertension, heart failure, high-altitude pulmonary edema, Raynaud's phenomenon, coronary artery disease, diabetes, and atherosclerosis, is presented.