Comparison of a CrossBoss First Versus Standard Wire Escalation Strategy for Crossing Coronary Chronic Total Occlusion: the "CrossBoss First" Trial

CrossBoss First is a single-blind randomized controlled trial that will randomize 246
patients undergoing clinically-indicated Chronic Total Occlusion Percutaneous Coronary
Intervention, to upfront use of the CrossBoss catheter vs. antegrade guidewire escalation
strategy The "CrossBoss First" study has two primary objectives. The primary efficacy
objective is to compare the procedure time required to cross the CTO or abort the procedure
with a CrossBoss first vs. antegrade wire escalation strategy. The investigators hypothesize
that upfront use of the CrossBoss catheter will be associated with shorter procedure time
required for CTO crossing compared with an antegrade wire escalation strategy.

The primary safety objective is to compare the frequency of procedural major adverse
cardiovascular events (MACE) with upfront use of CrossBoss vs. a guidewire escalation
strategy. The investigators hypothesize that upfront use of the CrossBoss catheter will be
associated with similar incidence of MACE compared with an antegrade wire escalation
strategy.

The secondary endpoints are: (1) technical and procedural success4-6; (2) total procedure
time (defined as the interval between administration of local anesthesia for obtaining
vascular access and removal of the last catheter); (3) fluoroscopy time to cross the CTO and
total fluoroscopy time; (4) total air kerma radiation exposure; (5) total contrast volume;
and (6) number of wires, microcatheters, balloons, and stents used.