VQI DELTA Paclitaxel Device Safety Analysis

The VQI-DELTA Paclitaxel Device Safety Analysis seeks to assess the comparative safety of paclitaxel coated balloons and stents in the treatment of PAD through analysis of the Vascular Quality Initiative (VQI) Peripheral Vascular Intervention (PVI) registry module using the DELTA system.

The objective of the VQI - DELTA Paclitaxel Phase I Study is to evaluate the relative safety of Paclitaxel used as an antiproliferative agent in the treatment of symptomatic PAD. The study will analyze Paclitaxel Drug Coated Balloons (DCB) and Paclitaxel Drug Eluting Stents (DES), both together and as unique exposures using propensity score matched survival analysis. If a mortality signal is detected, factors associated with late mortality will be further explored. Phase I is the retrospective component of the planned study, evaluating the 2-year survival of patients treated with a paclitaxel containing/eluting device to matched patients treated with non-paclitaxel devices for symptomatic PAD.

All proposed analyses will be performed using DELTA v3.x, which has the capability to prospectively monitor clinical data repositories for safety signals, and is designed to support risk-adjusted prospective safety surveillance analyses of complex clinical datasets.

Three principle analyses are planned:

• Paclitaxel DCB (including the Bard Lutonix, Medtronic In.Pact and Philips Spectranetics Stellarex DCB's) as compared with propensity matched patients treated with plain balloons.
• Paclitaxel delivering DES (including the Cook Zilver PTX and Boston Scientific Eluvia DES) as compared with propensity matched cases using bare metal stents (BMS).
• Patients treated with either Paclitaxel DCB or Paclitaxel DES compared with propensity matched controls (with DCB patients matched to patients treated with plain balloons, and DES patients matched to patients treated with BMS).

Inclusion criteria

• All patients who underwent endovascular interventional treatment of the femoral or popliteal arteries for symptomatic Peripheral Artery Disease.

Exclusion criteria

• In an effort to focus this safety evaluation on those patients being treated in accordance with accepted 'best practice' endovascular intervention strategies and 'on-label' use of devices, patients will be excluded from either exposure cases or controls if they received a balloon expandable stent or a balloon expandable stent graft in the treatment of femoral or popliteal disease. Balloon expandable stents were excluded because these stents have historically shown inferior patency and current best practice favors placement of self-expanding nitinol stents which were engineered for the femoral popliteal segment and tested in multiple trials for this indication 12-14.

Additionally, patients will be excluded (as either potential cases or controls) if their index procedure was performed for acute limb ischemia due to the different etiologies (embolism, in-situ thrombosis) as compared with chronic conditions as they have different treatment paradigms and higher major amputation and mortality rates.

In addition, patients with prior angioplasty or stenting of the superficial femoral artery (SFA)-popliteal segment will be excluded in order to avoid the possibility of improperly assigning paclitaxel exposure to the control group.