Which is a common site for EPS catheter placement?

• A. Right Ventricle
• B. HIS
• C. High Right Atrium (HRA)
• D. Coronary Sinus

Answer: (C)

During EPS, catheters are placed in several intracardiac sites to record and pace key parts of the conduction system. The high right atrium is typically the most commonly used atrial recording site because its location near the sinoatrial node and crista terminalis yields clear, high-amplitude atrial signals and is easily accessible via the venous route. This position provides a reliable reference for atrial activation during arrhythmias and for pacing to test conduction properties. Other sites have specific roles—the coronary sinus for left atrial and left ventricular access, the His bundle region for precise conduction (HV interval) measurements, and the right ventricle for ventricular pacing/recording and tachycardia maneuvers—but for routine catheter placement focused on atrial activity, the high right atrium is the most common choice.