We sought to evaluate the diagnostic accuracy of contrast-enhanced cardiac magnetic resonance (CMR) imaging for the detection of intracardiac masses and thrombus formation in patients with history of coronary artery disease (CAD) in comparison to transthoracic echocardiography (TTE) under clinical routine conditions. 171 patients with history of CAD (89 male, aged 34-89 years, median 63 ± 11) underwent TTE and CMR during routine clinical examinations. TTE and CMR were independently analysed regarding the presence of intracardiac thrombus formation, masses and related size, dimensions, shape and signal characteristics. TTE depicted intracavitary thrombus formation in 40/171 patients (23.4 %) and intracardiac mass in 12/171 patients (7.0 %). All masses revealed in TTE were correctly detected on CMR and confirmed by histology. However, CMR showed 15 additional thrombi and 3 additional intracardiac masses (p = 0.001) that were not seen in TTE. Patients with poor systolic function (LVEF <30 %) had misleading results when referred to TTE (19 vs. 27 thrombi detected, p < 0.01). The detection of intracardiac masses or thrombi was not significantly different in patient with LVEF >30 %, whereas CMR was superior when the LVEF was <30 %. Routine TTE in patients with CAD leads to lower detection rates of intracardiac masses and thrombus formation in patients with severely impaired EF. Consequently we are missing a significant amount of clinically relevant diagnosis when only assessing patients with TTE. In patients with CAD and severely impaired LVEF, CMR should be considered as first line imaging tool to detect or rule out intracardiac masses and thrombi.