PRISM: Thrombectomy system safe, effective for peripheral thromboembolism

LAS VEGAS — An aspiration thrombectomy system successfully removed thromboembolic occlusions in peripheral arteries of patients with a peripheral or visceral arterial occlusion enrolled in the PRISM trial.

Aspiration thrombectomy systems have been successfully used in patients with ischemic stroke, so researchers investigated whether one would work in patients with peripheral thromboembolic occlusions, Richard Saxon, MD, from San Diego Medical Imaging Group, said during a presentation at VIVA 16.

Saxon and colleagues tested the technology on 85 patients (mean age, 69 years; 41% women) with a peripheral or visceral arterial occlusion. At the beginning of the study, the system designed to treat ischemic stroke (Penumbra System, Penumbra) was used; later in the study, a similar system designed for treatment in the peripheral arteries (Indigo System, Penumbra) was used once it became commercially available, Saxon said.

PRISM was designed as a single-arm, multicenter registry to assess technical success and safety of the aspiration thrombectomy system. The primary outcome was improvement in vessel patency according to modified TIMI score. Safety outcomes included device-related adverse events and procedural serious adverse events.
The device could be used as front-line or salvage therapy and, after thrombus removal, adjunctive procedures were permitted if necessary, Saxon said.

In most cases, the target vessel was the popliteal artery (32.9%) or the superficial femoral artery (27.1%), Saxon said.

At baseline, all patients had TIMI 0 or 1 blood flow, but immediately after use of the thrombectomy device, 88.1% of patients had TIMI 2 or 3 flow, which rose to 96.4% after all adjunctive procedures. The rate of TIMI 3 flow after all procedures was 77.6%, he said.

Two periprocedural amputations occurred in patients that had non-healing ulcers pre-treatment and failed revascularization. No device- or procedure-related adverse events or serious adverse events were reported, he said. “Of course, these patients were extremely ill and did have adverse outcomes,” he said.

The device was used as front-line therapy 51.2% of the time. In those patients, TIMI 2 or 3 flow occurred 81.4% of the time after use of the device and 95.3% of the time after use of the device plus adjunctive therapy. In patients for whom the device was used as salvage therapy, TIMI 2 or 3 flow was restored 92.9% of the time.

“The [aspiration thrombectomy system] was relatively atraumatic and safe,” Saxon said. “It was technically successful in treating peripheral vascular occlusions. Normal flow was achieved in three-quarters of the patients overall using the device. It was effective as a front-line therapy [and] a salvage therapy.” – by Erik Swain

Reference:

Saxon R, et al. Late-Breaking Clinical Trials. Presented at: VIVA 16; Sept. 18-22, 2016; Las Vegas.

Disclosure: The study was funded by Penumbra. Saxon reports consulting for, receiving honoraria and receiving research funding from Penumbra and W.L. Gore and Associates and receiving research funding from Bard/Lutonix.