This tool calculates atrial conduction time from ECG measurements based on the horizontal width of the P-wave in small boxes and the ECG paper recording speed.
Estimated P-Wave Duration:
0 ms
Clinical Interpretation: 0
P-wave duration represents the time taken for electrical impulses to travel through the atria, indicating the efficiency of atrial depolarization.
Formula: Duration (ms) = (Boxes / Paper Speed) * 1000
Duration (ms) = (Boxes / Paper Speed) * 1000
Example: A P-wave spanning 2.5 small boxes on a strip recorded at 25 mm/s paper speed.
A normal P-wave duration is typically less than 120 milliseconds (3 small boxes at 25 mm/s).
Prolonged duration (>= 120ms) often indicates left atrial enlargement or intra-atrial conduction delay.
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