Smartwatches With ECG
Fitbit Sense 2 Review: A Holistic Approach to Stress and Heart Health
The Fitbit Sense 2 is a refined health wearable that prioritizes long-term wellness tracking through its comprehensive sensor suite. Its primary clinical features include an FDA-cleared ECG app and an Irregular Heart Rhythm Notification (IHRN) system, both of which were validated in the massive Fitbit Heart Study. The device introduces the cEDA (continuous electrodermal activity) sensor, which passively monitors skin conductance throughout the day to identify 'Body Response' events related to stress. While its ECG app is a single-lead (Lead I) spot-check tool requiring user initiation, the IHRN system works passively in the background using PPG technology. Clinical validation studies have shown the IHRN system has a positive predictive value of 98.2% for detecting AFib during periods of inactivity. The Sense 2 also monitors blood oxygen (SpO2) and skin temperature variations overnight. While it lacks the third-party app ecosystem of Wear OS or watchOS, its 6-day battery life and focused health metrics make it a powerful tool for longitudinal health surveillance.