Endothelial dysfunction from oxidative injury has recently emerged as a common link between the failing heart and kidneys in CRS. The endothelium plays an obligatory role in cardiovascular homeostasis, and impaired endothelium-mediated nitric oxide (NO) bioavailability is the hallmark of endothelial dysfunction. There is a high prevalence of endothelial dysfunction in our Asian HF patients, with a greater degree of dysfunction seen in those with CRS. We hypothesise that targeting endothelial dysfunction may improve clinical status among Asian patients with CRS.