Six-month outcomes of the FLEX First arteriovenous (AV) registry, assessing the safety and efficacy of the Flex vessel prep (VP) system (VentureMed) in combination with standard percutaneous transluminal angioplasty (PTA) for haemodialysis access dysfunction, have demonstrated a 70% overall rate of target lesion primary patency, with no serious adverse events in the short term.
Ari Kramer (Spartanburg Regional Hospital, Spartanburg, USA) presented the results in a podium first presentation during the vascular access masterclass session at the 2025 Charing Cross (CX) symposium (23–25 April, London, UK) covering access revision controversies. The Flex VP system uses a kinetic endovascular micro-incision creation technology which is designed to create long, precise micro-incisions for controlled vessel preparation.
The FLEX FIRST multicentre observational registry included 130 haemodialysis patients with arteriovenous fistula (AVF) or arteriovenous graft (AVG) presenting with vascular access dysfunction from four clinical sites in the United States. Structured evaluation was undertaken at one, six, and 12-month intervals to assess short and long-term outcomes.
Kramer reported that the study population represented a diverse group of patients, with 37% female, 60% of Black patients, 27% with cephalic arch lesions and 25% with arteriovenous grafts.
On safety, Kramer detailed that there were no serious adverse events through one month, with a 0.8% complication rate, representing a single minor dissection treated successfully with a stent graft.
On efficacy, Kramer reported a 70.7% target lesion primary patency rate through six months, with “robust” outcomes seen across all patient cohorts. This compares favourably to historical controls with conventional angioplasty.
In particular, Kramer highlighted the 76.3% patency rate for cephalic arch lesions, which he said represents a “significant achievement”, as these lesions typically exhibit poor outcomes with standard angioplasty alone. “These are clinically meaningful results in difficult settings,” Kramer said.
“These results continue the positive outcomes demonstrated in the FLEX AV registry, and confirm that FLEX is not just facilitating angioplasty—it’s fundamentally improving lesion behaviour,” he commented.
