Sinus Tachycardia sometimes presents with Partially Hidden P waves. The heart rate is still >100 to approximately 150 b/min (it sometimes is a little faster than 150 b/min). NOTE: The interpretation is still Sinus tachycardia.
Sinus Tachycardia with Partially Hidden P Waves. The Rhythm is regular and the rate is 150 b/min in this example below. Because the p waves are partially hidden, the PRI is INDETERMINATE. The interpretation is Sinus tachycardia.
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