Interpretation: This rhythm is benign and requires no medical treatment.
Phasic increases and decreases in heart rate are usually associated with inspiration and expiration, and are most noticeable during sleep.
Since the rate is above 100 beats per minute, this is a tachyarrhythmia.
In this slide show, you will see how abnormal ECG patterns differ from normal tracings.
Sinus tachycardia in a patient with a damaged heart, however, can result in life-threatening decreases in cardiac output.
Arrhythmias may occur constantly or intermittently. They can occur because of myocardial ischemia, drug toxicity, electrolyte imbalance, or overactivity of the sympathetic or parasympathetic nervous systems.
If treatment is necessary to increase heart rate, atropine is the drug of choice.
Interpretation: The impulse originates in the SA node and follows normal conduction pathways.
When interpreting rhythm strips, remember to use all of these steps, as they are equally important.