E-4031 is primarily utilized in research settings to study cardiac electrophysiology due to its specific action as a potent blocker of the hERG potassium channel. This channel plays a critical role in the repolarization phase of the cardiac action potential, and E-4031 is often used to investigate arrhythmias and the mechanisms underlying long QT syndrome. By inhibiting hERG, it helps researchers understand the impact of delayed repolarization on heart function and assess the potential cardiotoxicity of new drugs. Additionally, it serves as a tool in preclinical studies to evaluate the safety profiles of pharmaceutical compounds, particularly those that may inadvertently interfere with hERG channels.