We introduce the notion of filtered perversity of a filtered different
ial complex on a complex analytic manifold X, without any assumptions
of coherence, with the purpose of studying the connection between the
pure Hedge modules and the L-2-complexes. We show that if a filtered d
ifferential complex (M-.,F-.) is filtered perverse then DR-1(M-., F.)
is isomorphic to a filtered D-module; a coherence assumption on the co
homology of (M,F) implies that, in addition, this D-module is holonomi
c. We show the converse: the de Rham complex of a holonomic Cohen-Maca
ulay filtered D-module is filtered perverse.