Electrocardiographic Artifacts

A 34-year-old nurse complained of recurrent attacks of palpitations in the past 2 months. The palpitations were not related to any specific event or physiological changes. Twenty-four-hour ambulatory electrocardiographic monitoring of her cardiac rhythm using a Holter recorder did not reveal any arrhythmias, even though she reported several attacks of palpitations during the recording. The electrocardiogram (ECG) in Figure 1 was recorded following an emotionally stressful period and when she complained of having palpitations. The patient was alert at the time, and her blood pressure was normal.

1. The interpretation of the ECG is which of the following?

   • supraventricular tachycardia

   • ventricular tachycardia

   • atrial flutter with 1:1 atrioventricular conduction

   • ventricular flutter

   • none of the above

2. Artifact may be caused by which of the following?

   • muscle tremors

   • Parkinson’s disease

   • poor skin-electrode contact

   • electrical interference

   • errors in electrode position

   • any of the above...