In a first-time data release, Dierk Scheinert presented six-month outcomes from the DETOUR trial of percutaneous bypass in long segment femoropopliteal occlusions at the Leipzig Interventional Course (LINC; 24–27 January, Leipzig, Germany).
The DETOUR (PQ Bypass) percutaneous bypass procedure is designed to achieve the same end result as open bypass surgery. Revascularisation is via a modular stent graft bypass and uses the femoral vein as a conduit. The technology is currently unavailable for sale and is undergoing clinical trials, Scheinert, from the Division of Interventional Angiology, University-Hospital, Leipzig, Germany, told delegates.
Commenting on the results of the study, Scheinert said: “The clinical performance [of the DETOUR bypass procedure] in severe lesions (95% chronic total occlusion and 93% TASC II D, 28.6cm mean lesion length) demonstrates this novel therapy’s potential for complex patients without a durable endovascular option.”
The DETOUR percutaneous bypass is achieved using a trio of proprietary devices including the Torus stent graft (self-expanding nitinol wire frame encapsulated in expanded polytetrafluoroethylene), PQ Snare (an over-the-wire dual-caged scaffold that captures and extracts guidewires through the tibial vein) and PQ Crossing Device (a spring-loaded guidewire support and delivery system that creates initial artery-vein-artery communication).
Revascularisation of long, complex superficial femoral artery occlusions has traditionally required open surgical bypass for long-term success. Whilst endovascular techniques and technologies have matured, a durable solution for these severe lesions is still lacking, noted Scheinert. “Percutaneous bypass, a novel endovascular approach, may provide the durability associated with open surgery while reducing morbidity and mortality associated with more invasive interventions,” he explained.
The DETOUR study is a prospective, multicentre single-arm study designed to assess the safety and performance of the technology and technique. It includes one of the largest prospective series evaluating the percutaneous treatment of superficial femoral artery occlusions >25cm.
Patients needed to have femoropopliteal lesions ≥10cm in length that were considered chronic total occlusions (100% stenosis); diffuse stenosis (>50% stenosis) with moderate to heavy calcification; or in-stent restenosis (>50% stenosis) in order to be included. They also needed to have more than one patent tibial artery to the foot and a patent femoral vein ≥10mm in diameter, or a duplicate femoral vein.
The 60 patients included were mostly men, around 65 years of age, and most smoked. A third of those had had a previous peripheral intervention and a fifth of the group had diabetes. A majority, over 95%, were classified as Rutherford class 3. With regard to lesions, the mean length was 28.6±15.1cm, and 96.7% were total occlusions.
The primary safety endpoint was defined as major adverse events (death, target vessel revascularisation, or target limb amputation) at 30 days. Six-month results of DETOUR showed that the major adverse rate was 3.4% (n=59). There were no deaths or amputations, but 3.4% (2/59) of patients required a target vessel revascularisation. This figure went up to 10.2% (6/59) at six months.
The primary efficacy endpoint was the primary patency (no evidence of clinically significant stenosis [≥50%] within, immediately above, or below the treated arterial segment based on duplex ultrasound [PSV>2.5]). At six months, the primary patency rate was 84.7%. The investigators also recorded high procedural and technical success rates of >95%.
“There was no deep venous thrombosis in the PQ bypass segment and no health impact on the venous system at six months; ankle brachial index was significantly improved at six months compared to baseline (p<0.0001); and 94% of patients improved ≥1 Rutherford class at six months as compared to baseline (p<0.0001),” Schienert said.