If you need hospitalisation, the costs are covered by your basic insurance. If you have a natura (in kind) policy, you will only be covered if you go to a hospital that is contracted by your insurance. It is advised to contact your insurance company to find out which hospitals are contracted. In case of emergencies, the costs are covered regardless of the kind of insurance (in kind or restitution).
In all cases, you have to pay your eigen risico (deductible) first.