HydroDynamic contrast Recanalization (HDR): Description of a new crossing technique for coronary chronic total occlusions.

Background: Intraplaque delivery of contrast has been utilized during percutaneous coronary interventions (PCI) of chronic total occlusions (CTO) to delineate anatomy and to facilitate wire crossing. Its utility as a tool to accomplish primary crossing of CTOs has not been described or validated.

Aims: We describe a new technique leveraging the diagnostic and therapeutic roles of intraplaque contrast injection to accomplish primary crossing of CTOs: HydroDynamic contrast Recanalization (HDR).

Methods: HDR is an antegrade crossing method for coronary CTOs based on the synergistic use of contrast microinjections and polymer jacketed wires. We present a retrospective, first-in-man, case series utilizing HDR for CTO PCI in patients with favorable CTO anatomy (visible proximal segment and identifiable distal target). The primary outcome was procedural success. The secondary outcome was any procedural complications.

Results: A total of 43 patients with 45 CTOs underwent CTO PCI with HDR. Mean patient age was 64.3 ± 11 years. The mean Japanese CTO and PROGRESS CTO scores were 2.3 ± 0.7 and 1.8 ± 0.7, respectively. CTO complexity was high, with an ambiguous or blunt cap in 34 occlusions (76%); lesion length ≥ 20 mm in 27 occlusions (60%); and moderate/heavy calcification in 36 occlusions (80%). Procedural success using HDR was 100%. There were no complications.

Conclusions: This study shows the utility of HDR in CTO PCI. HDR appears to be a safe and promising new contrast-based primary crossing technique in selected patients. This strategy warrants further evaluation in larger prospective studies.