Abstract
BACKGROUND: Atrial fibrillation (AF) has been linked to an increased risk of cardiovascular death, overall mortality and heart failure in patients with type 2 diabetes mellitus (T2DM). The present study investigated the additive effects of paroxysmal AF on left ventricular (LV) function and deformation in T2DM patients with or without AF using the cardiovascular magnetic resonance feature tracking (CMR-FT) technique. METHODS: The present study encompassed 225 T2DM patients differentiated by the presence or absence of paroxysmal AF [T2DM(AF+) and T2DM(AF-), respectively], along with 75 age and sex matched controls, all of whom underwent CMR examination. LV function and global strains, including radial, circumferential and longitudinal peak strain (PS), as well as peak systolic and diastolic strain rates (PSSR and PDSR, respectively), were measured and compared among the groups. Multivariable linear regression analysis was used to examine the factors associated with LV global strains in patients with T2DM. RESULTS: The T2DM(AF+) group was the oldest, had the highest LV end‑systolic volume index, lowest LV ejection fraction and estimated glomerular filtration rate compared to the control and T2DM(AF-) groups, and presented a shorter diabetes duration and lower HbA1c than the T2DM(AF-) group. LV PS-radial, PS-longitudinal and PDSR-radial declined successively from controls through the T2DM(AF-) group to the T2DM(AF+) group (all p < 0.001). Compared to the control group, LV PS-circumferential, PSSR-radial and PDSR-circumferential were decreased in the T2DM(AF+) group (all p < 0.001) but preserved in the T2DM(AF-) group. Among all clinical indices, AF was independently associated with worsening LV PS-longitudinal (β = 2.218, p < 0.001), PS-circumferential (β = 3.948, p < 0.001), PS-radial (β = - 8.40, p < 0.001), PSSR-radial and -circumferential (β = - 0.345 and 0.101, p = 0.002 and 0.014, respectively), PDSR-radial and -circumferential (β = 0.359 and - 0.14, p = 0.022 and 0.003, respectively). CONCLUSIONS: In patients with T2DM, the presence of paroxysmal AF further exacerbates LV function and deformation. Proactive prevention, regular detection and early intervention of AF could potentially benefit T2DM patients.