Supraventricular tachycardia: The sudden onset of the symptoms and the history of prior episodes led the treating physicians to administer an adenosine challenge. Flutter waves were then visualized clearly.

BACKGROUND

A 45-year-old woman presents to the hospital with a sudden onset of palpitations and chest pressure.

Hint

The patient's blood pressure is within the normal range. The heart rate is 140 beats per minute. The patient states that she had an identical episode in the past.

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