Cardiac masses are currently studied using multimodality imaging. For diagnosis, different imaging techniques that can provide complementary information are used. Cardiac magnetic resonance imaging (MRI) has become a fundamental tool for this type of pathology owing to its ability to provide tissue characterization, spatial accuracy, and the anatomic relationships of the different structures. This study presents a series of four clinical cases with an initial diagnosis of a cardiac mass. All cases were evaluated at a single center, and patients were aged 57 to 72 years. An etiological study was conducted on all patients using different imaging techniques, including MRI. This study describes the diagnostic and therapeutic procedures of the four cases, which included two intracardiac metastases and two benign tumors. Cardiac MRI was decisive in the diagnostic process, determining the clinical decision-making in all four cases. Cardiac MRI has emerged as a pivotal technique in the diagnosis of cardiac masses. It can provide a highly accurate histological diagnosis without the need for invasive techniques.