CHF, EF 55% 6.
 No history of heart disease
(ROOT (NP (NP (NP (NN CHF)) (, ,) (NP (NP (NN EF) (CD 55) (NN %)) (CD 6))) (. .)))
(ROOT (NP (NP (DT No) (NN history)) (PP (IN of) (NP (NN heart) (NN disease)))))
( ( ( CHF , ) ( ( EF ( 55 % ) ) 6 ) ) . )
( ( No history ) ( of ( heart disease ) ) )