Background: Elderly patients and those with multiple concomitant disorders are nowadays qualified for cardiac surgery procedures, which is related to higher incidence of the postoperative complications. Aim: The aim of this study was a retrospective analysis of the perioperative factors potentially contributing to occurrence of cardiac incidents after cardiac surgery procedures. Methods: Data of 552 patients of the cardiac surgery clinic were collected and analyzed. Data concerning medical history, previous treatment, laboratory results, additional tests results, operation and hospitalization period were examined. Results: In the study population of 552 patients, cardiac complications were observed in 49.5% of them. Among cardiac complications, the most frequent were supraventricular tachycardia (30.1%) and atrial fibrillation (27.4%). Postoperative bradycardia occurred in 5.25% patients, half of whom required temporary cardiac pacing. Conclusions: The risk of incidence of cardiac complications after cardiac surgery procedures depends mostly on patient’s age, EuroSCORE Logistic (ESL) score, left ventricular ejection fraction, myocardial hypertrophy, presence of paroxysmal AF and coincidence of nephrological complications. The necessity of performing more than one heart defibrillation after removing aortic cross-clamp favors early postoperative bradycardia. Considering the outcomes of this study, continuing reperfusion at least until 1/3 of the aortic cross-clamp time brings no additional benefits to the patients.