MyoMobile Study: App-based Activity Coaching in Patients with Heart Failure and Preserved Ejection Fraction

Heart failure (HF) affects more than 15 million people in Europe and represents the leading cause of hospitalization. The prevalence of HF is increasing, which has been attributed to an ageing population with subsequently higher prevalence of predisposing risk factors (e.g. arterial hypertension, type-2-diabetes, obesity), a better survival, and more effective treatment of precursors (e.g. myocardial infarction). In the community, heart failure with preserved ejection fraction (HFpEF) is the most common HF phenotype. Currently, the benefit of medical therapies is limited to patients with heart failure with reduced ejection fraction (HFrEF) only, whereas no specific medical therapy is currently approved for patients with HFpEF.

In HF patients, physical inactivity and a sedentary lifestyle lead to disease progression and increased mortality, and an increase of physical activity is positively correlated with improved outcome. Guidelines from the Heart Failure Society of America recommend at least 30 minutes of moderate-intensity activity for ≥ 5 days/week (i.e. at least 150 min/week). Unfortunately, exercise recommendations are poorly implemented in daily clinical practice and even patients enrolled in supervised exercise training programs have been reported to show low adherence.

The MyoMobile study has been designed to assess the effect of a 12-week, app-based coaching program on physical activity in patients with HFpEF. Physical activity including daily step count will be assessed by accelerometry and, in addition, a pedometer will be used to measure the daily step count and provide direct feedback to the patient. Accelerometers provide an objective and continuous assessment of physical activity during patients' daily life over longer periods and may therefore reflect the true effect of the activity coaching intervention on physical activity more accurately than intermittent supervised exercise tests such as the six minute walk test. These efforts are complemented by a comprehensive (sub)clinical and molecular characterization of HFpEF patients at baseline and after the follow-up period of 12 weeks. In order to evaluate the potential effect of awareness for physical activity and of surveillance, due to participants wearing a pedometer throughout the study period, two intervention groups will be investigated. This will allow for the effect of an individualized, app-based coaching intervention, compared to standard care in patients with HFpEF, to be deciphered.

Inclusion criteria

• Age ≥ 45 years
• Diagnosis of HFpEF

• LVEF > 40% by any imaging modality at screening within 4 months prior to study entry
• Current HF symptoms as defined as presence of dyspnea according to New York Heart Association [NYHA] functional class I to III at screening visit
• Stable HF treatment for at least 4 weeks prior to screening
• At least one of the following 3 criteria need to be fulfilled: (1) NT-proBNP ≥ 300pg/ml; (2) Hospitalization for HF within the past 12 months; (3) Symptom(s) of HF requiring treatment with diuretic(s) for at least 30 days prior to screening visit
• Wearing time of the physical activity monitor for at least 4 days during the baseline assessment
• Average daily step count during baseline assessment ≥ 1,000 steps per day and < 10,000 steps per day

Exclusion criteria

• Acute decompensated HF requiring augmented therapy with diuretic agents, vasodilator agents, and/or inotropic drugs
• Participants who are non-ambulatory managed or use mobility assistive devices such as motorized devices or wheelchairs
• Acute coronary syndrome (including myocardial infarction), cardiac surgery, other major cardiovascular surgery or urgent percutaneous coronary intervention (PCI) within 3 months prior to visit 1 or an elective PCI within 30 days after study enrolment
• Probable alternative diagnoses that in the opinion of the investigator account for the patient's HF symptoms (i.e., dyspnea, fatigue)
• Participants with physical activity impairment primarily due to conditions other than HF such as:

• Participants unwilling or unable to wear or to operate study measurement devices for the phases required
• Exertional angina
• Inflammatory or degenerative joint disease
• Peripheral vascular disease
• Neurologic disease affecting activity or mobility (e.g. peripheral neuropathy)
• Foot ulcer (e.g. diabetic foot syndrome)
• Prosthetic limbs
• Current chemotherapy and/or radiation therapy for treatment of active cancer
• Medical or psychological conditions that would jeopardize an adequate and orderly conduct or completion of the study