Cardiac ablation catheters commonly used for the diagnosis and treatment of arrhythmias are small in diameter and require extensive finger grip and dexterity for safe maneuverability during procedures. This is especially important in the pediatric population where the cardiac structures are smaller and potentially more variable as a result of congenital anatomic anomalies. We developed a novel catheter grip accessory tool for improved control and maneuverability of cardiac ablation catheters. Mechanical testing of the tool demonstrated it could grip the catheter with an average force of 0.031 kN and transfer an average torque of 0.0392 N-m before slipping, both well above forces experienced in normal clinical use. During tensile testing, the tool fractured at an average force of 0.554 kN. At the point of failure, testing found that the electrical conduction and resistance of the catheter remained unchanged. In simulated use testing, the tool was able to translate torque more accurately to the catheter tip compared to manual manipulation of the catheter. This novel tool has the potential to reduce physician muscle exertion in ablation procedures and increase the safety profile when manipulating catheters within the heart.