Last night, he began having chest pain at rest.
 patient has chest pain at rest
(ROOT (S (NP (JJ Last) (NN night)) (, ,) (NP (PRP he)) (VP (VBD began) (S (VP (VBG having) (NP (NN chest) (NN pain)) (PP (IN at) (NP (NN rest)))))) (. .)))
(ROOT (S (NP (NN patient)) (VP (VBZ has) (NP (NN chest) (NN pain)) (PP (IN at) (NP (NN rest))))))
( ( Last night ) ( , ( he ( ( began ( ( having ( chest pain ) ) ( at rest ) ) ) . ) ) ) )
( patient ( ( has ( chest pain ) ) ( at rest ) ) )