A 15-year-old female with two fainting spells and normal orthostatic blood pressures. Which test should be ordered first?

A 15-year-old female with two fainting spells and normal orthostatic blood pressures. Which test should be ordered first?

• A. Echocardiogram
• B. 12-lead electrocardiogram
• C. Tilt table testing
• D. Treadmill exercise testing

Answer: (B)

Evaluating syncope in a teenager starts with quickly checking the heart’s rhythm and electrical activity. A 12-lead ECG is the best first test because it can detect life‑threatening or treatable cardiac causes of fainting, such as abnormal QT intervals or other conduction delays, pre‑excitation syndromes (like WPW), or patterns suggestive of arrhythmias. Even when orthostatic blood pressures are normal, an ECG helps rule in or out cardiac rhythm problems that could require different management. If the ECG is normal and the history suggests reflex (vasovagal) syncope, tilt-table testing may be considered later to confirm that reflex mechanism. An echocardiogram is more helpful when there is suspicion of structural heart disease from exam findings or abnormal ECG. Treadmill exercise testing is typically reserved for evaluating exercise‑induced symptoms or arrhythmias in older patients or specific scenarios, not as a first-line test in this clinical context.

Evaluating syncope in a teenager starts with quickly checking the heart’s rhythm and electrical activity. A 12-lead ECG is the best first test because it can detect life‑threatening or treatable cardiac causes of fainting, such as abnormal QT intervals or other conduction delays, pre‑excitation syndromes (like WPW), or patterns suggestive of arrhythmias. Even when orthostatic blood pressures are normal, an ECG helps rule in or out cardiac rhythm problems that could require different management.

If the ECG is normal and the history suggests reflex (vasovagal) syncope, tilt-table testing may be considered later to confirm that reflex mechanism. An echocardiogram is more helpful when there is suspicion of structural heart disease from exam findings or abnormal ECG. Treadmill exercise testing is typically reserved for evaluating exercise‑induced symptoms or arrhythmias in older patients or specific scenarios, not as a first-line test in this clinical context.