Cardiothoracic surgery, including coronary artery bypass grafting, valve replacement, and transplantation, has considerably advanced, improving patient survival and outcomes. However, non-pulmonary postoperative complications remain a major concern, contributing to morbidity and mortality. These complications encompass cardiovascular events, vascular injuries, infections, and device-related issues that can severely impact recovery. Early diagnosis and timely intervention are crucial to mitigating risks and improving patient outcomes. Advanced imaging modalities such as computed tomography, magnetic resonance imaging, and echocardiography play a pivotal role in identifying and characterizing complications before clinical deterioration occurs. This review highlights the spectrum of acute non-pulmonary complications following cardiothoracic surgery, emphasizing the diagnostic value of imaging in guiding clinical decision-making. By improving the awareness of imaging findings associated with postoperative complications, radiologists and clinicians can facilitate early detection, enabling prompt surgical or medical interventions. A multidisciplinary approach that integrates imaging surveillance with clinical assessment is essential for optimizing patient care and reducing long-term morbidity.