What is the primary purpose of an invasive electrophysiology study (EPS)?

• A. Diagnose arrhythmia mechanism, map conduction substrates, and guide ablation strategy
• B. Evaluate heart valves for replacement
• C. Measure lipid levels
• D. Assess exercise capacity

Answer: (A)

An invasive electrophysiology study is used to uncover how the heart’s electrical system creates tachyarrhythmias by diagnosing the mechanism, mapping the conduction substrate, and guiding ablation. By placing catheters inside the heart and performing programmed stimulation, clinicians can induce arrhythmias in a controlled setting, pinpoint the circuits and critical tissue responsible for the rhythm, and determine where energy should be delivered to disrupt the arrhythmia. This information directly informs the ablation strategy, helping to target the exact area that sustains the abnormal rhythm. Other tests like evaluating valves, measuring lipids, or assessing exercise capacity serve different purposes and are not what EPS is designed to do.