BNP was elevated at 7882.
 History of heart failure
(ROOT (S (NP (NN BNP)) (VP (VBD was) (VP (JJ elevated) (PP (IN at) (NP (CD 7882))))) (. .)))
(ROOT (NP (NP (NN History)) (PP (IN of) (NP (NN heart) (NN failure)))))
( BNP ( ( was ( elevated ( at 7882 ) ) ) . ) )
( History ( of ( heart failure ) ) )