White matter hyperintensities (WMHs), which are common in elderly people and contribute to age-related disability, can coexist with cardiac injury. It remains unclear whether cardiac biomarkers are associated with WMHs.To investigate this question, we prospectively recruited patients with cardioembolic stroke due to atrial fibrillation (AF) and/or rheumatic heart disease (RHD). Four cardiac biomarkers were measured: myoglobin, high-sensitivity cardiac troponin T (hs-cTnT), creatine kinase-MB, and terminal pro-brain natriuretic peptide. WMHs in periventricular and deep white matter were assessed separately.In the entire sample of 171 patients, 120 (70.2%) presented with WMHs, of whom 18 (10.5%) presented with moderate to severe deep white matter hyperintensities (DWMH) and 55 (32.2%) presented with moderate to severe periventricular hyperintensities (PVH). Risk of moderate to severe PVH, after adjusting for confounders, was 2.460-fold higher in patients with high myoglobin levels than in those with low levels, and the risk was 2.608-fold higher in patients with high hs-cTnT levels than in those with low levels. There were no significant associations between any of the 4 cardiac biomarkers and moderate to severe DWMH.This prospective observational study provides new evidence of the potential relationship of cardiac biomarkers with WMHs in patients with cardioembolic stroke due to AF and/or RHD. We found that elevated myoglobin levels and high hs-TnT levels were independently associated with the presence of moderate to severe PVH. Further studies are required to test our findings and explore whether cardiac biomarkers contribute directly to WMHs pathogenesis.