A comprehensive multi-functional device platform that can be variably configured by clinician operators for patient-specific anatomies and clinical situations for treating complex and total occlusions is provided. This device platform enables physicians of any skill level to effectively treat the most challenging and complex lesions/occlusions more conveniently in less time. The Functionally Integratable Catheter System (“FICS System”) represents a system of “functional units” that can be configured together to operate synergistically, and comprises at least four main “functional units,” including: (a) FICS Support Catheter; (b) FICS Dilator; (c) FICS PTA Catheter; and (d) FICS Lock-Grip Handle. Each “functional unit” can be provided in a pre-assembled form by the manufacturer, intended to be configured into variable combinations by clinician operators.