We investigated the usefulness of gadolinium-enhanced magnetic resonance (Gd-MR) imaging for diagnosis of right ventricular (RV) infarction in 14 patients with acute inferior infarction. Myocardial perfusion images with thallium 201 and technetium 99m pyrophosphate (dual single-photon emission computed tomography: dual SPECT) and haemodynamic data were obtained on admission. Patients were classified into three groups based on dual SPECT and Gd-MR findings: no accumulation in the right ventricle (negative, Type 1), posterior RV infarction (Type 2) and anterior and posterior RV infarction (Type 3). No patients exhibited the haemodynamic criteria for RV infarction (a mean right atrial pressure above 10 mmHg and a ratio of mean right atrial pressure to pulmonary artery wedge pressure above 0.8). Dual SPECT identified RV infarction in eight patients (three Type 2 and five Type 3, 57% of the total). Gd-MR imaging also identified eight patients (57%) as positive (five Type 2 and three Type 3). Our results showed that Gd-MR imaging was not only useful for diagnosis of RV infarction, but also equal to dual SPECT in sensitivity and specificity, and superior to it as regards acquisition time and assessing the spatial anatomy of heart. In conclusion, Gd-MR imaging is superior to dual SPECT for detection of RV infarction.