Clinically silent cardiac disease is frequently observed in rheumatoid arthritis (RA), and cardiovascular complications are the leading cause of mortality in RA. We sought to evaluate the myocardium of young RA patients without known cardiac disease using cardiac magnetic resonance (CMR), including T1/T2 mapping sequences. Eighteen RA patients (median age 41 years, 83% females) mainly with low disease activity or in remission and without any known cardiovascular disease were prospectively included to undergo CMR. A control group consisted of 10 sex- and age-matched patients without RA or any known structural cardiovascular disease. Heart chambers size and left/right ventricular systolic function were similar in patients with RA and controls. Signs of myocardial oedema were present in up to 39% of RA patients, including T2 time above cut-off value in 7 patients (39%) in comparison to none of the controls (p = 0.003) and T2 signal intensity ratio above the cut-off value in 6 patients (33%) and in none of the controls (p = 0.06). Extracellular volume was similar in both groups signifying a lack of diffuse fibrosis in studied group of RA patients. There were also no signs of late gadolinium enhancement (LGE) in either group except for one patient with RA who was found to have prior silent myocardial infarction. No correlation was found between markers of disease severity and markers of oedema observed on CMR in patients with RA. Nevertheless, patients with increased T2 time (≥50 ms) were more likely to have X-ray erosions (p = 0.02) and a longer duration between symptom onset and diagnosis (p = 0.02). Finally, there were no significant arrhythmias on 24-h ECG Holter monitoring in RA patients. CMR features of myocardial oedema without signs of myocardial fibrosis were found in 39% of young RA patients without known heart disease or cardiac symptoms. Presence of myocardial oedema was associated with X-ray erosions and a longer duration between symptom onset and diagnosis. The clinical significance of the observed early myocardial changes accompanying RA requires additional studies.