Multidetector-row computed tomography (MDCT) plays an essential role in oncologic imaging as the modality of mapping out the treatment strategy at staging, assessing response to the treatment, and following up patient outcome after the treatment. Even without electrocardiogram gating, MDCT provides accurate information about the heart. In the group of oncologic patients, different tumoral and non-tumoral-related heart disorders can be found, for example, metastatic cardiac involvement (approximately 10% of patients with lung or breast cancer will develop metastases to the heart), paraneoplastic cardiac disorders, non-tumor-related heart disorders, and chemotherapy- and radiotherapy-related cardiac side effects. MDCT plays a role in the detection of these entities. We show the non-electrocardiogram-gated MDCT findings of oncology-related cardiac disorders to encourage radiologists to recognize and report cardiac findings in oncologic patients. Appropriate knowledge of tumoral and non-tumoral-related MDCT features allows a complete evaluation of oncologic patients with ancillary cardiac findings. An adequate knowledge of the patient's medical history, previous treatments, and concomitant illnesses is essential to interpret heart findings in oncologic patients who undergo MDCT.