Objective: Pericardial effusion is a frequent finding in patients who undergo cardiac surgery. There are currently limited data providing information regarding the factors that may contribute to postoperative pericarditis. The aim was to evaluate laboratory and echocardiographic features that may influence the presence of pericardial effusion 6 to 8 weeks following coronary artery bypass grafting (CABG). Materials and Methods: This was a prospective cross-sectional study that included 90 patients after CABG operation who were divided into two groups. A total of 32 (35.56%) patients with pericardial effusion on follow-up echocardiography formed the first group and 58 patients without pericardial effusion the second group, which were compared in respect to components that were taken prior to the operation. Results: The groups did not differ regarding sex (males 65.62% vs 63.79%, P = .86) or age (59.59 ± 9.29 vs 61.69 ± 10.71, P = .35). Platelet count (184.74 ± 58.79 vs 222.62 ± 88.97, P = .03) and left ventricular (LV) global longitudinal strain (GLS) (−14.64 ± 6.86 vs −16.96 ± 4.1, P = .04) demonstrated statistical significance. Conclusion: Prolonged postoperative pericardial effusion in small amounts may be found in patients, with preoperative lower thrombocyte count and LV GLS, which could be possible predisposing factors.