The aim of the current study is to develop and validate an algorithm based on seismocardiography recordings to detect heart failure. Echocardiography will be used as the golden standard for defining patients with heart failure.

Seismocardiography is inspired from methods for the analysis of seismic activity and can be used to describe the heart's movements using a specially developed sensor placed on the patient's chest. The project aims to describe the motion of the heart using automated computer analysis of the seismocardiography signal for development of a simple method for the analysis of myocardial performance.

Inclusion Criteria:

• Male or female, aged 18 years or older
• Clinically suspected heart failure, and referred to an outpatient clinic
• Be able and willing to comply with the clinical investigational plan
• Have signed the informed consent form

Exclusion Criteria:

• Known HF
• Known atrial fibrillation
• Acute coronary syndrome
• Implanted donor heart, mechanical heart, mechanical heart pump, pacemaker or Cardioverter Defibrillator (ICD)
• Implanted electronic equipment in the area above and around the heart
• Significant operation scars, abnormal body shape, fragile or compromised skin in the seismocardiographic recording area (fourth left Inter Costal space and xiphoid process)
• Pregnancy

Extension study:

Inclusion criteria

1. Male or female, aged 18 years or older
2. Newly diagnosed HFREF
3. Be able and willing to comply with the clinical investigational plan
4. Have signed the informed consent form

Exclusion criteria

1. Known atrial fibrillation
2. Acute coronary syndrome
3. Implanted donor heart, mechanical heart, mechanical heart pump, pacemaker or Cardioverter Defibrillator (ICD)
4. Implanted electronic equipment in the area above and around the heart
5. Significant operation scars, abnormal body shape, fragile or compromised skin in the seismocardiographic recording area (fourth left Inter Costal space and xiphoid process)
6. Pregnancy

Patients with clinically suspected heart failure

Extension study:

Patients with newly diagnosed HFrEF