This patient's symptomatic episodes are intermittent and short-lived; therefore, a 30-day wearable recorder with looping memory is the best diagnostic strategy to uncover the nature of her palpitations. These recorders are worn continuously and record a continuous “loop” of heart rhythm. When the patient experiences symptoms, she can depress a button and the device captures the rhythm before, during, and after the symptoms. Loop recorders are useful for recording episodes accompanied by syncope or presyncope and for episodes that are too short to be captured by a patient-triggered event recorder.

A patient-triggered event recorder (without looping memory) is useful for recording infrequent episodes that last long enough (1-2 minutes) for the patient to hold the device to the chest and trigger it to capture the heart rhythm. A self-applied event recorder is not useful for brief episodes because the time taken to apply the monitor may be longer than the symptomatic episode.

If a patient has an abnormal cardiovascular examination or is demonstrated to have an arrhythmia, echocardiography should be performed to evaluate for the presence of structural heart disease. In this patient, however, the cardiac examination is normal, and there is no documentation of an arrhythmia at this point. Many patients with symptoms suggestive of arrhythmia are found to have causes for their symptoms that are not related to heart rhythm.

An exercise treadmill stress test would be reasonable if the episodes were precipitated by exertion or exercise, but this patient's episodes are not associated with exertion.

Given the infrequency of this patient's symptoms, 48-hour ambulatory electrocardiographic monitoring is not likely to capture the symptomatic episodes.

In patients with very infrequent or rare episodes (>30 days between episodes), an implanted loop recorder may be appropriate. These devices, which are approximately the size of a pen cap and are implanted under the skin of the chest next to the sternum, have several years of battery life. Although they are invasive, these devices have a higher diagnostic yield than other forms of outpatient heart rhythm monitoring.