Rationale and methods of the IDOMENEO health outcomes of the peripheral arterial disease revascularisation study in the GermanVasc registry.

BACKGROUND: Atherosclerotic disease of the lower extremity arteries (PAD) remains a significant burden on global healthcare systems with increasing prevalence. Various guidelines on the diagnosis and treatment of patients with PAD are available but they often lack a sufficient evidence base for high-grade recommendations since randomized and controlled trials (RCT) remain rare or are frequently subject to conflicts of interest. This registry trial aims to evaluate the outcomes of catheter-based endovascular revascularisations vs. open-surgical endarterectomy vs. bypass surgery for symptomatic PAD on medical and patient-reported outcomes.

METHODS AND DESIGN: The study is a prospective non-randomized multicentre registry trial including invasive revascularisations performed in 10 000 patients treated for symptomatic PAD at 30 to 40 German vascular centres. All patients matching the inclusion criteria are consecutively included for a recruitment period of six months (between May and December 2018) or until 10 000 patients have been included in the study registry. There are three follow-up measures at three, six, and 12 months. Automated completeness and plausibility checks as well as independent site visit monitoring will be performed to assure high internal and external validity of the study data. Study endpoints include relevant major cardiovascular and limb events and patient-reported outcomes from two Delphi studies with experts in vascular medicine and registry-based research.

DISCUSSION: It remains unclear if results from RCT can reflect daily treatment practice. Furthermore, great costs and complexity make it challenging to accomplish high quality randomized trials in PAD treatment. Prospective registry-based studies to collect real-world evidence can help to overcome these limitations.