Final answer:
PSVT deviates from NSR by having a higher heart rate, an abrupt onset and termination of rhythm, and possible abnormalities in the appearance or discernibility of P waves.
Step-by-step explanation:
The question asks how Paroxysmal Supraventricular Tachycardia (PSVT) deviates from Normal Sinus Rhythm (NSR). PSVT is an abnormally fast heart rhythm originating above the heart's ventricles. It is characterized by a sudden onset and an equally sudden termination of rapid heartbeats, which can range from 150 to 250 beats per minute. In contrast, NSR indicates a normal heart rate (60 to 100 beats per minute) and rhythmic beating pattern initiated by the sinus node, the natural pacemaker of the heart. The main differences between PSVT and NSR include:
- Heart Rate: PSVT shows a higher heart rate compared to the normal rate in NSR.
- Rhythm Regularity: Although PSVT has a regular rhythm, its onset and termination are abrupt, which differs from the consistent rhythm of NSR.
- P Wave: In PSVT, P waves may be difficult to discern or could have an abnormal shape, whereas NSR features regular and consistent P waves preceding every QRS complex.
Individuals with PSVT may experience symptoms such as palpitations, shortness of breath, or dizziness, which are not typical of NSR.