AVP and heart failure: It is notable that copeptin results were higher pre-operatively and at day 1 post-TSS in those with an eGFR <30 ml/min/1.73 m2 (pre-operative mean 7.79 pmol/l, day 1 mean 17.95 pmol/l) and heart failure (pre-operative mean 15.14 pmol/l, day 1 mean 13.4 pmol/l).