CHF, EF 55% 6.
 Congestive heart failure
(ROOT (NP (NP (NP (NN CHF)) (, ,) (NP (NP (NN EF) (CD 55) (NN %)) (CD 6))) (. .)))
(ROOT (NP (JJ Congestive) (NN heart) (NN failure)))
( ( ( CHF , ) ( ( EF ( 55 % ) ) 6 ) ) . )
( Congestive ( heart failure ) )