The individual restrictions of daily life for patients with PAD are more important than statistical facts for mortality and morbidity. Intermittent claudication causes a progressive reduction of the pain-free walking distance (PWD) as an expression of a worsening PAD. This decrease in physical capability results in a decline of mental health and relevantly reduces the patients' quality of life (QoL).

Supervised exercise therapy (SET) is a cornerstone in the conservative management of intermittent claudication and extends the PWD. Even though SET is easy to practice and highly cost effective, the adherence to perform SET on a regular base is rather low. The underuse of exercise can be partly explained by the lack of institutional resources, but also by both patients' and physicians' lack of interest in exercise.

Mobile health (mHealth) technologies increase the incentives and provide digital support for patients with PAD on several treatment levels. They might lead to a higher adherence to exercise training and offer new scopes in patient-centered healthcare, but so far studies show opposite results. Because app stores are flooded with health and fitness apps, specific support tools are highly desired by patients with PAD and PAD-specific solutions are missing so far. Based on this background, the investigators developed a smartphone app named TrackPAD to provide PAD-specific support for SET.

The TrackPAD pilot study was designed as a 2-armed randomized controlled trial and included patients with diagnosed and symptomatic PAD. Patients were randomized by the Center for Clinical Studies in Essen using the TENALEA software into 2 groups. The control group included participants with standard care and no further mobile intervention. The intervention group included participants with standard care and additional mHealth-based self-tracking of their physical activity using trackPAD.

Inclusion Criteria:

• Diagnosis of lower extremity PAD based on (and/or):

  • ABI ≤ 0.9 in at least one legs
  • Invasive or non-invasive imaging of stenotic lower extremity artery disease
  • Endovascular or surgical revascularization of lower extremity artery

• PAD Fontaine Stage IIa/b

• Smartphone with possibility to use TrackPAD: Android ≥ 5.0 or IOS ≥ 11.0

• Written informed consent prior to any study procedures, including a specified follow-up evaluation

• Best-medical treatment in the last 2 months in accordance with standard guidelines

Exclusion Criteria:

• Wheelchair bound, use of walking aid or walking impairment due to another cause than PAD
• Below or above knee amputation
• Acute or critical limb ischemia
• PAD Fontaine Stage I or III / IV
• No German knowledge
• Severe cognitive dysfunction
• Congestive heart failure with NYHA III-IV symptoms
• Active congestive heart failure requiring the initiation or uptitration of diuretic therapy
• Angina pectoris with CCS class 3-4 symptoms or myocardial infarction or stroke in the last 3 months
• Active arrhythmia requiring the initiation or uptitration of anti-arrhythmic therapy
• Severe valve disease