Four preliminary studies have found patients with heart failure may benefit from L-arginine, however the data is from small studies that used variable dosages and delivery techniques (IV vs. oral) with transient endpoints of variable clinical significance. Subjects in these studies were taking other medications for heart failure, including digoxin, diuretics, angiotensin-converting enzyme inhibitors and glyceryl trinitrate, though in three studies, the medications were discontinued prior to the study. Further research on the effect of L-arginine use in patients with heart failure is needed.
