FlowCardia's Crosser Studied in Peripheral CTO Treatment

September 22, 2010—In an analysis of the RESPECT registry, the Crosser chronic total occlusion (CTO) recanalization catheter system (FlowCardia, Inc., Sunnyvale, CA) demonstrated an 86.8% technical success rate in patients with peripheral CTOs, as well as a high success rate in treating patients with multilevel CTOs, which can add to case difficulty. Raghotham R. Patlola, MD, presented the data at the Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium in Washington, DC. 

TCT Daily reported details of the presentation.

According to Dr. Patlola, the average CTO length was 220.5 ± 98.3 mm. Dr. Patlola noted that although success was most important, measurements of Crosser actuation time, fluoroscopic time, and procedural time also were encouraging.

As reported in TCT Daily, the retrospective, nonrandomized, multicenter RESPECT analysis examined the safety and efficacy of the Crosser device as first-line therapy in 2,050 patients with peripheral CTOs. Data were collected in a registry database between October 2007 and June 2010. The investigators analyzed CTO location and length, device used, success rates, time to crossing, and complication data. The primary and secondary endpoints were crossing success and safety, respectively.

According to Dr. Patlola, the study was conducted at multiple centers by multiple interventionists of all skill levels. A wide variety of artery types were treated in the study: superficial femoral (50.2%), popliteal (13.4%), peroneal (10.9%), posterior tibial (10.9%), anterior tibial (9.9%), iliac (4.7%), and common femoral (1.3%). In-stent occlusions were treated in 15% of the cases. A large cohort of patients had multilevel occlusions, adding to the difficulty of those cases; however, the technical success rate remained favorable in these patients (84.8%) compared with the overall 86.8% technical success rate.

Crosser actuation time ranged from 9 seconds to 300 seconds (mean time, 242 seconds). In 23% of patients, the actuation time was < 30 seconds. The average fluoroscopic time was 26.5 ± 19.5 minutes, and the total procedural time was 91 ± 32 minutes. There were no clinically relevant complications.

Dr. Patlola explained that the Crosser devices use ultrasonic energy to disrupt plaque and thrombus in the CTO directly distal to the tip of the catheter, allowing the wire to pass through the occlusion. A small generator connected to the end of the catheter supplies the ultrasonic energy, creating a current delivered to piezoelectric crystals in the transducer. The crystals expand and contract to create a mechanical vibration to aid in the recanalization of the CTO.

Three types of Crosser devices were used in the study: the Crosser 18 (0.018-inch guidewire-compatible, “robust” 125-cm catheter, used on above-the-knee CTOs with a large diameter and straight vessels), the Crosser 14S (0.014-inch guidewire-compatible, “supportive” 146-cm catheter, used on above- and below-the-knee CTOs in large tortuous vessels and in small, straight distal anatomy), and the Crosser 14P (0.014-inch guidewire-compatible, “flexible” 146-cm catheter, used on below-the-knee CTOs in small, tortuous distal anatomy).

“We've used this as a first-line therapy, and this represents a very good, valuable tool in our international toolbox for treatment of peripheral artery disease,” commented Dr. Patlola. He noted, however, that randomized, multicenter data are needed to validate the Crosser device.