AGTR1 and congestive heart failure: Valsartan, (2S)-3-methyl-2-[pentanoyl-[[4-[2-(2H-tetrazole-5-yl)phenyl]phenyl]methyl]amino]butanoic acid, is a lipophilic, nonpeptide, tetrazole derivative, a selective antagonist of angiotensin II type 1 receptor (AT1), which is widely used in many cardiovascular conditions like hypertension or chronic heart failure.