Cardiac surgery is an advanced medical specialty that involves technical procedures with significant risks of morbidity and mortality. Although cardiac surgery is performed within the ethical framework specific to the medical profession, this medical field faces specific ethical challenges and dilemmas. These are generated, on the one hand, by its surgical nature and the technological progress transposed—among others—into minimally invasive cardiac surgery techniques, and on the other hand, by the particular profile of the patients. In this chapter, the author examines the ethical challenges faced by cardiac surgery, using the lens of the duty-based ethical framework formed by the four principles formulated by Beauchamp and Childress, i.e., autonomy, beneficence, non-maleficence, and justice, recognizing that in certain clinical contexts other ethical frameworks could be more appropriate, such as the utilitarianism in the scarce allocation of resources.