The goal of this observational study is to validate the efficacy of the Hexoskin Medical System (HMS) for its intended use (i.e., manual assessment of cardiac rhythm disturbances) in non-critical adult participants who are suspected of having an arrhythmia or have evidence of arrhythmia requiring monitoring via 24-hour Holter monitor.

The main questions it aims to answer are:

1. Whether the HMS ECG recordings can be used to accurately detect cardiac beats when compared with the Holter monitor
2. Whether there are good agreements between the HMS and Holter monitor in ECG characteristics
3. Whether the HMS ECG recordings can be used to accurately classify cardiac rhythm/rhythm disturbance when compared with the Holter monitor
4. What is the accuracy of using HMS ECG recordings to detect cardiac beats
5. What is the accuracy of using HMS ECG recordings to identify cardiac rhythm/rhythm disturbance

Participants will wear the HMS and the Holter monitor at the same time to record ECG signals. Researchers will evaluate the ECG recordings acquired from both devices and assess the above questions.

Inclusion Criteria:

• Provision of signed and dated informed consent form.
• Stated willingness to comply with all study procedures and availability for the duration of the study.
• Male or female, aged 21 years or older.
• Participants must be suspected of having an arrhythmia or have evidence of arrhythmia requiring monitoring via 24-hour Holter monitor.

Exclusion Criteria:

• Body circumference that is not covered by the HMS Shirt sizing chart
• Presence of pacemaker or Implantable Cardioverter-Defibrillator (ICD) devices
• Known allergic reactions to silver or polyamide/polyester/elastane
• Known allergic reactions to ECG gel electrodes
• Documented medical condition or illness requiring intensive medical treatment or care

Consecutive patients consulting the cardiology clinics

There is no plan to make IPD available.