Patient's rhythym was thought to represent VTach for which the patient was given lidocaine without effect.
 The patient has a regular rate and rhythm. 
(ROOT (S (NP (NP (NN Patient) (POS 's)) (NN rhythym)) (VP (VBD was) (VP (VBN thought) (S (VP (TO to) (VP (VB represent) (NP (NP (NN VTach)) (SBAR (WHPP (IN for) (WHNP (WDT which))) (S (NP (DT the) (NN patient)) (VP (VBD was) (VP (VBN given) (S (NP (NN lidocaine)) (PP (IN without) (NP (NN effect)))))))))))))) (. .)))
(ROOT (S (NP (DT The) (NN patient)) (VP (VBZ has) (NP (DT a) (JJ regular) (NN rate) (CC and) (NN rhythm))) (. .)))
( ( ( Patient 's ) rhythym ) ( ( was ( thought ( to ( represent ( VTach ( ( for which ) ( ( the patient ) ( was ( given ( lidocaine ( without effect ) ) ) ) ) ) ) ) ) ) ) . ) )
( ( The patient ) ( ( has ( a ( regular ( ( rate and ) rhythm ) ) ) ) . ) )