Patients with presumed atrial fibrillation will undergo monitoring with the device and Holter ECG.

Patients with presumed sinus rhythm will undergo monitoring with the device and Holter ECG.

Patients with presumed sinus rhythm and frequent extrasystoles will undergo monitoring with the device and Holter ECG.

Participants will use the wearable (the tested device) to record at least 2 minutes of photoplethysmography and 6-lead ECG. In addition, each subject will be monitored with synchronous ECG Holter monitoring (with eMotion Faros 90).

The wearable system comprises of two integrated components: a photoplethysmography (PPG) and a 6-lead ECG of the device. It works as described below.

First, an automatic PPG algorithm will indicate whether atrial fibrillation is suspected. The rhythm assessment of PPG algorithm is based on pulse regularity.

Next, a 6-lead ECG is acquired by the wearable. The rhythm assessment of ECG is based on P waves and regularity of QRS complexes. A diagnosis is made by independent cardiologists.

The conclusion of a whole system comprising of both described methods will be compared with a gold standard multi-lead Holter ECG. This standard ECG is also evaluated by independent cardiologists.

An automatic PPG algorithm will indicate whether atrial fibrillation is suspected. The rhythm assessment of PPG algorithm is based on pulse regularity. As a separate diagnostic tool it will be compared with a gold standard multi-lead Holter ECG which is assessed by independent cardiologists.