Evaluation of left ventricular function and twist in patients with diabetic cardiovascular autonomic neuropathy by speckle tracking imaging

OBJECTIVE: To evaluate left ventricular (LV) function and twist in patients with diabetic cardiovascular autonomic neuropathy (CAN) by two-dimensional speckle tracking imaging (STI). METHODS: STI was performed in 56 subjects with type 2 diabetes mellitus (DM) (35 with DM only: group A, 21 with CAN: group B) and 34 normal subjects (Control) from LV short-axis view. LV peak systolic, peak early (E') and peak late (A') diastolic circumferential strain in 18 myocardial segments were measured at the levels of mitral annulus, papillary muscle and apex and the rotation at mitral annulus and apex levels were also measured. LV peak systolic and the ratio of E' and A' of global and three levels, twist, untwisting rate and untwisting half-time were calculated. RESULTS: In group A, compared with control group, LV peak systolic radial circumferential strain has no significant difference (P > 0.05), E'/A' was reduced (P < 0.05), twist at aortic valve closure and twist at mitral valve opening were significantly increased (P < 0.05), untwisting rate reduced, and untwisting half time delayed. In group B, compared with control group and group A, circumferential strain parameters [(-12.64 ± 6.49)% vs. (-19.11 ± 9.98)% and (-21.14 ± 10.13)%, P < 0.05] and E'/A' [(0.90 ± 0.35) vs. (1.24 ± 0.47) and (1.98 ± 0.63), P < 0.05] were significantly decreased, twist at aortic valve closure [(19.08 ± 5.62)° vs. (16.57 ± 2.84)° and (14.36 ± 4.06)°, P < 0.05] and twist at mitral valve opening [(13.99 ± 2.31)° vs. (11.36 ± 2.63)° and (9.04 ± 5.63)°, P < 0.05] were significantly increased, untwisting rate [(0.40 ± 0.28)%/ms vs. (0.46 ± 0.14)%/ms and (0.53 ± 0.21)%/ms, P < 0.05] reduced, and untwisting half time [(489.61 ± 97.14) ms vs. (445.21 ± 54.53) ms and (410.60 ± 50.23) ms, P < 0.05] delayed. CONCLUSION: Speckle tracking imaging could be used to evaluate early changes on LV twist deformation and LV systolic function in patients with type 2 diabetes mellitus.