Twelve-month results from the randomised, multicentre DEFINITIVE AR pilot study suggest that there is a benefit to adding directional atherectomy in long and calcified lesions prior to using a drug-coated balloon in comparison to the use of a drug-coated balloon alone. Data from the trial were presented yesterday by Thomas Zeller, Bad Krozingen, Germany, who is a study principal investigator alongside Gunnar Tepe, Rosenheim, Germany.

DEFINITIVE AR was designed to assess the effect of treating a lesion with directional atherectomy (Medtronic/Covidien’s SilverHawk or TurboHawk plaque excision systems) followed by a paclitaxel-coated balloon (Bayer HealthCare’s peripheral paclitaxel-coated angioplasty catheter with Paccocath Technology), collectively referred to as DAART (directional atherectomy + anti-restenotic therapy), in order to generate early hypotheses for further research in this therapy area.

Claudicants (Rutherford clinical category 2–4) with 7–15cm superficial femoral and/or popliteal lesions were randomised 1:1 to either DAART (n=48) or to the paclitaxel-coated balloon alone (n=54). Patients with severely calcified lesions were assigned to a non-randomised registry arm and were treated with DAART (n=19). Baseline patient and lesion characteristics did not differ between the DAART and drug-coated balloon arms. 

Technical success, defined as ≤30% residual stenosis following the protocol-defined treatment at the target lesion, was significantly higher in the DAART arm vs. the drug-coated balloon arm (89.6% vs. 64.2%, p=0.004). According to Zeller, there were significantly fewer flow-limiting dissections reported in patients treated with DAART vs. drug-coated balloon alone (2% vs 19%, p=0.01). Technical success in the DAART registry group was 84.2% and incidence of flow-limiting dissections was 0%.

At 12 months, per cent stenosis in the randomised groups was 33.6±17.7 for the DAART arm vs. 36.4±17.6 for the drug-coated balloon arm. Duplex ultrasound patency (PSVR ≤2.4, without target lesion revascularisation) was 93.4% for the DAART arm and 89.6% for the drug-coated balloon arm. Angiographic patency (≤50% stenosis and without target lesion revascularisation) was 82.4% in the DAART arm and 71.8% in the drug-coated balloon arm. In the DAART cohort lesions with a residual stenosis <30% post atherectomy did show a trend towards better angiographic patency at one year (94.1% vs. 68.8%).

“This rigorously performed pilot study suggests an added benefit for DAART over drug-coated balloons alone in long and calcified lesions. Further investigation in larger, prospective, statistically-powered randomised trials is warranted. Patients will be followed out to 24 months to assess durability of the results,” Zeller said.