Z visa requirements? Medical check up? (Guangzhou)

I'm trying to get my Z Visa from the Chinese Embassy in The Netherlands. I have the official invitation from my new employer and Chinese Republic.

--> Does anybody know if a X Ray and ECC (ECG) is really necessary for obtaining my Z Visa?

Already visited the Embassy 4 times this week and they keep sending me back home... Can anybody help me?

Thank you in advance!
Vanessae