Major findings are the following: (1) AVP secretion was relatively suppressed in patients with severe AS; (2) peri-procedural P-AVP had no significant association with severity of heart failure or AS (non-osmotic pathway) but was associated with plasma osmolality dominantly due to blood urea nitrogen (osmotic pathway); (3) peri-procedural P-AVP had no significant impact on post-TAVI outcome. The gene discussed is AVP; the disease is aortic stenosis.