Purpose <p>Inefficient energy delivery to blood remains a primary challenge in cardiac radiofrequency ablation (RFA), limiting procedural efficacy. This paper introduces and computationally validates a novel multi-surface microelectrode catheter (MSMC) designed to enhance targeted energy delivery and improve overall procedural efficiency.</p> Methods <p>A 3D multiphysics computational model coupling electrical, thermal, fluid-dynamic, and mechanical fields was developed to simulate RFA. The performance of the MSMC was systematically compared against a traditional catheter by analyzing its energy distribution and thermal lesion characteristics under both standard (10–18 W vs. 30 W) and high-power short-duration (25 W vs. 60 W) protocols, assessing the impact of varying catheter angles (vertical, 45°, and parallel), and exploring its potential for real-time lesion monitoring via impedance analysis.</p> Results <p>The MSMC directed over 75% of its energy to the myocardium, a threefold improvement over the traditional catheter (~22%), allowing the creation of comparable lesions with 40% less power. The design demonstrated high stability across different orientations. Furthermore, analysis of its impedance characteristics via Cole-Cole plots revealed a greater sensitivity for real-time lesion monitoring compared to the traditional catheter.</p> Conclusions <p>The MSMC's design, which synergizes a multi-surface electrode structure with a contact-based discharge strategy, enables more efficient and predictable lesion formation. This computational proof-of-concept study confirms its potential to improve the safety, efficacy, and real-time control of RFA procedures, offering a promising pathway for the development of next-generation therapeutic devices.</p>