WASHINGTON, D.C.—Use of BridgePoint Medical's Chronic Total Occlusion (CTO) Crossing and Re-entry system increased procedural success and shortened procedural and fluoroscopy times when compared with other CTO-specific devices, according to a presentation at the annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium, sponsored by the Cardiovascular Research Foundation (CRF).
R. Michael Wyman, MD, and colleagues at the Torrance Memorial Medical Center in Torrance, Calif., conducted the non-randomized FAST-CTO (Facilitated Antegrade Steering Technique in CTO) trial, which evaluated the safety and efficacy of the BridgePoint CTO device in 149 patients at 20 U.S. centers, and also compared the device to previous historical control clinical trials evaluating other CTO-specific devices.
“The BridgePoint system represents a novel technology for the recanalization of CTOs,” said Wyman. The device is equipped with three components including the Stingray and CrossBoss catheters and the Stingray CTO Re-entry guidewire.
According to Wyman, the CrossBoss catheter uses multiple wires and a blunt distal tip that is spun rapidly through a patient’s CTO using an external torquing device that can achieve distal positions. If a subluminal position is achieved via this process, the Stingray CTO Re-entry device is used in conjunction with the Stingray CTO Orienting Balloon Catheter, a flat device that orients itself within the subluminal space and exits through the vessel's true lumen under low pressure inflation.
Wyman and colleagues used primary effectiveness as the endpoint of the trial and defined technical success as guidewire placement and distal placement with use of the BridgePoint system. Additionally, the researchers looked at 30-day major adverse cardiovascular event (MACE) rates, as well as fluoroscopy and procedure time.
During the trial, CTO was required to be refractory to the guidewire crossing for the following criteria:
- A previous failed attempt within 12 months of revascularization of the CTO;
- Attempt during the index procedure to cross with the guidewire that failed within 10-15 minutes of fluoro time; or
- Achieved suboptimal positioning.
Seventy-one percent of the study population had a CTO in the right coronary artery (RCA), 19 percent were in the left anterior descending (LAD) and 10 percent in the left circumflex (LCX) coronary artery.
According to Wyman, 41 percent of patients had experienced previously failed CTO procedures, which he stressed took place at high-volume facilities by experienced operators, regarding them as “true” procedure failures.
FAST-CTO trial results showed a technical success rate of 77 percent, while the MACE rate was 4.8 percent. The average main procedure time was 105 minutes and fluoroscopy time was 44 minutes, which is “satisfactory for these difficult CTOs,” he noted.
While the overall success rate was 77 percent, Wyman noted that a learning curve was present during the trial. A 70 percent success rate during the first half of the trial rose to 86 percent during the second half, which Wyman linked to operator experience and technique alterations.
During the trial, two patient deaths occurred. Wyman noted these patient deaths were at distant time points from the procedure itself—18 days and 21 days post procedure—one from respiratory arrest and one from cardiac arrest. Additionally, six MIs and five perforations occurred— four occurred in the perforated branches.
The FAST-CTO trial enrolled more patients than other CTO-specific trials (CROSSER, SafeCross and Frontrunner) and also had longer, more challenging lesions. Technical success reported for those other trials were 61 percent, 54 percent and 58 percent, respectively.
Additionally, MACE rates were 4.8 percent during the FAST-CTO trial compared to 8.8, 6.9, and 8 percent in the CROSSER, SafeCross and Frontrunner trials, respectively.
“The FAST-CTO trial compared very favorably with other studies,” he said. And, despite the fact that 41 percent of patients had previously failed procedure attempts, the success rate was still 77 percent.
“In conclusion, the BridgePoint medical system can provide high rates of success in anatomically challenging CTO lesions with minimal complications. The system may allow for shorter procedural and fluoroscopy times and it compares favorably with other CTO specific devices in terms of efficacy and safety.”