Utility of the Safe-Cross-guided radiofrequency total occlusion crossing system in chronic coronary total occlusions (results from the Guided Radio Frequency Energy Ablation of Total Occlusions Registry Study).

The Safe-Cross radiofrequency guidewire (IntraLuminal Therapeutics, Carlsbad, California) combines 3 capabilities: (1) steerability of a conventional 0.014-in intermediate-stiffness guidewire, (2) optical coherence reflectometry to warn the operator when the wire tip approaches within 1 mm of the vessel wall, and (3) delivery of radiofrequency energy pulses to the wire tip to facilitate passage through an occluded segment. The Guided Radio Frequency Energy Ablation of Total Occlusions Registry was a prospective, nonrandomized, multicenter registry that enrolled 116 patients who had long-term coronary total occlusions and in whom a >10-minute good-faith attempt to cross the occlusion using conventional guidewires had failed. The median known duration of occlusion was 22 months (32%; >1 year), and the median length of the occluded segment was 25 mm (25%; >30 mm). Device success was achieved in 63 of 116 of patients (54.3%), and major adverse events occurred in 6.9%, consisting predominantly of isolated increases in cardiac enzymes with no procedure-related deaths, Q-wave myocardial infarctions, or emergency bypass operations. Clinical perforation occurred in 2.6% of patients; of these, perforation in only 1 patient (0.9%) was adjudicated to be directly related to the Safe-Cross radiofrequency wire rather than to the stiff and/or hydrophilic wires used after an inability to advance with the Safe-Cross. Based on these data, the device has been approved in Europe and was recently (January 2004) granted 510K clearance by the Food and Drug Administration.