ECG vs PPG: Key Distinctions in Heart Activity Monitoring > 자유게시판

ECG and PPG function as different technologies used to measure heart activity, but they function through unique mechanisms and deliver different types of data. ECG stands for electrocardiogram and captures the heart’s electrical activity produced by the heart as it beats. These signals are detected by placing electrodes on the skin, typically on the torso and extremities. The output signal shows the duration and amplitude of the electrical impulses that initiate each heartbeat. This makes ECG highly accurate for detecting irregular heart rhythms, heart attacks, and other electrical abnormalities in the heart.

The acronym PPG refers to photoplethysmogram and relies on optical sensing to monitor fluctuations in blood perfusion in the vessels. A PPG sensor, commonly found in fitness trackers and smartwatches, emits light—usually green or infrared into the skin and quantifies light absorption changes. During each arterial surge, the optical density changes slightly, permitting pulse rate approximation and occasionally reveal flow irregularities. PPG is great for continuous, noninvasive monitoring during daily activities, but it is easily disrupted by motion, skin tone, and external conditions, which can affect its accuracy.

ECG provides a comprehensive analysis of the heart’s cardiac conduction system, PPG is indicative of the mechanical side of the heartbeat—the pulse wave caused by blood being pumped through arteries. ECG is the gold standard in medical environments for evaluating cardiovascular pathology, whereas PPG is more commonly used non-clinical fitness tracker assessment and pulse rate approximation. An increasing number of wearables integrate both methods to provide more comprehensive insights, but it’s crucial to recognize that they are not interchangeable. ECG is better for diagnosing specific heart problems, while PPG is useful for monitoring trends over time in daily routines.