Subclinical left ventricular deformation and microvascular dysfunction in T2DM patients with and without peripheral neuropathy: assessed by 3.0 T cardiac magnetic resonance imaging

BACKGROUND: Diabetic peripheral neuropathy (DPN) has been shown to be independently associated with cardiovascular events and mortality. This study aimed to evaluate changes in left ventricular (LV) microvascular perfusion and myocardial deformation in type 2 diabetes mellitus (T2DM) patients with and without DPN, as well as to investigate the association between myocardial perfusion and LV deformation. METHODS: Between October 2015 and July 2022, one hundred and twenty-three T2DM patients without DPN, fifty-four patients with DPN and sixty age‑ and sex‑matched controls who underwent cardiovascular magnetic resonance imaging were retrospectively analyzed. LV myocardial perfusion parameters at rest, including upslope, time to maximum signal intensity (TTM), max signal intensity (max SI), and myocardial strains, including global radial, circumferential and longitudinal strain (GRS, GCS and GLS, respectively), were calculated and compared among the groups with One‑way analysis of variance. Univariable and multivariable linear regression analyses were performed to explore the independent factors influencing LV myocardial perfusion indices and LV strains in diabetes. RESULTS: The LV GLS, upslope and max SI were significantly deteriorated from controls, through patients without DPN, to patients with DPN (all P < 0.001). Compared with controls, TTM was increased and LV GRS and GCS were decreased in both patient groups (all P < 0.05). Multivariable regression analyses considering covariates showed that DPN was independently associated with reduced upslope, max SI and LV GLS (β = − 0.360, − 2.503 and 1.113, p = 0.021, 0.031 and 0.010, respectively). When the perfusion indices upslope and max SI were included in the multivariable analysis for LV deformation, DPN and upslope (β = 1.057 and − 0.870, p = 0.020 and 0.018, respectively) were significantly associated with LV GLS. CONCLUSION: In patients with T2DM, there was more severe LV microvascular and myocardial dysfunction in patients with complicated DPN, and deteriorated subclinical LV systolic dysfunction was associated with impaired myocardial circulation.