Ultimate Longevity Bible

Tool / wearable

Portable / Wearable ECG

Last updated 2026-07-02· Last reviewed 2026-07-02· 1 min read

Reviewed by the Ultimate Longevity Bible editorial team. Educational reference — not medical advice. See disclaimer.

Device options

  • KardiaMobile: pocket single-lead (6-lead variant available); highest overall clinical validation.
  • Apple Watch (Series 4+): on-demand single-lead ECG + continuous PPG-based AFib screening.
  • Fitbit Sense: on-demand ECG with FDA clearance.
  • Samsung, Withings, Garmin: various offerings with varying regulatory status.

Evidence

  • Apple Heart Study and Fitbit Heart Study: watch-based screening identifies previously-undiagnosed AFib in a meaningful fraction of screened adults.
  • Positive-predictive value depends on prevalence — screening asymptomatic young adults produces mostly false positives.

Use cases

  • Palpitations investigation: on-demand capture during symptoms.
  • AFib recurrence monitoring: after cardioversion or ablation.
  • Older-adult stroke prevention: watch-based passive AFib screening in adults with CHA₂DS₂-VASc ≥ 2.

Limits

  • Single-lead only — cannot diagnose ischaemia.
  • False-positive AFib alerts are common at population scale.
  • Watch-based screening in low-risk adults may produce more harm than benefit.

More on this topic

Related entries

Atrial fibrillation, Apple Watch, Stroke.

More tools