Society of Nuclear Medicine (India) Guidelines for Procedure and Reporting of Equilibrium Gated Radionuclide Angiocardiography: Revisiting Treasure Trove Lost in Plain Sight

Equilibrium gated radionuclide angiocardiography (ERNA) is a well-established functional radionuclide imaging technique used for the assessment of global and regional ventricular function, with primary emphasis on left ventricular performance. ERNA can be performed under resting conditions as well as during stress, including exercise and dobutamine infusion, allowing comprehensive evaluation of ventricular function across varying hemodynamic states. Data acquired during ERNA are processed to generate a range of parametric images that allow qualitative and quantitative analysis. These include assessment of regional wall motion, calculation of left ventricular ejection fraction, and evaluation of systolic and diastolic functional parameters. This article outlines the fundamental technical aspects of ERNA, focusing on acquisition protocols and data processing, describes the derivation and interpretation of key functional parameters, and provides a reporting format.