He was discharged on medical therapy and returns today for elective CABG.
 the patient has triple vessel disease
(ROOT (S (NP (PRP He)) (VP (VBD was) (VP (VBN discharged) (PP (IN on) (NP (NP (NP (JJ medical) (NN therapy)) (CC and) (NP (NNS returns)) (NP (NN today))) (PP (IN for) (NP (JJ elective) (NNP CABG))))))) (. .)))
(ROOT (S (NP (DT the) (NN patient)) (VP (VBZ has) (NP (JJ triple) (NN vessel) (NN disease)))))
( He ( ( was ( discharged ( on ( ( ( ( ( medical therapy ) and ) returns ) today ) ( for ( elective CABG ) ) ) ) ) ) . ) )
( ( the patient ) ( has ( triple ( vessel disease ) ) ) )