Augmented and Mixed Reality in Cardiac Surgery: A Narrative Review

<b>Background:</b> Augmented reality (AR) and mixed reality (MR) promise to enhance anatomical understanding, spatial orientation, and workflow in cardiac surgery. Their clinical adoption remains limited and the translational path is incompletely defined. <b>Methods:</b> A PubMed search was conducted by two independent reviewers from database inception through July 2025 and identified peer-reviewed, English-language articles describing peri- or intra-operative AR/MR applications in cardiac surgery. Relevant clinical, preclinical, technical, and review articles were selected for inclusion based on scope and content. Given the narrative approach and heterogeneity across studies, findings were synthesized qualitatively into application domains. <b>Results:</b> Fourteen studies were included. Five domains emerged: (1) preoperative planning and patient-specific modelling-MR enhanced spatial orientation and planning for minimally invasive and valve procedures; (2) intraoperative navigation and visualization-AR improved targeting and interpretation with preclinical overlay errors ≈ 5 mm; (3) physiological/functional guidance-thermographic AR detected ischemia in vivo with strong correlation to invasive thermometry; (4) robotic integration and workflow optimization-AR-guided port placement and stepwise robotic adoption supported the feasibility of totally endoscopic CABG; (5) AR-based early rehabilitation. <b>Conclusions:</b> Early clinical and preclinical evidence supports AR/MR feasibility and utility for visualization and orientation in cardiac surgery. Priorities include deformable, motion-compensated registration, ergonomic integration with robotic platforms, and multicentre trials powered for operative efficiency and patient outcomes.