Background: Cardiac surgery (CS) may be associated with several organic repercussions responsible for the appearance of cardiac risk factors during the postoperative period. These, associated with prolonged hospital length of stay (LoS), may trigger critical manifestations in individuals undergoing this surgical procedure. To investigate the relationships between postoperative cardiac risk factors, LoS, and changes in functioning state. Methods: Patients undergoing reconstructive, substitutive, or corrective cardiac surgeries were evaluated. The presence of postoperative cardiovascular risks was assessed using the InsCor score, while LoS and functionality were collected from medical records. Results: One-hundred patients with a mean age of 59.2±12.3 years were included. Significant correlations between functionality and both the hospital and Intensive Care Unit (ICU) LoS (p<0.0001, ρ= 0.56; p=0.002, ρ=0.29, respectively), as well as between hospital LoS and the number of comorbidities (p=0.003, ρ=0.28) were found. No significant relationships were observed between the number of postoperative risk factors and LoS. Conclusions: Functionality and comorbidities are associated with increased hospital and ICU LoS in patients undergoing cardiac surgery.