Abstract
BACKGROUND: Type 2 diabetes mellitus (T2DM) causes myocardial dysfunction and has been linked to an increased risk of unfavorable cardiovascular events. However, the additive effects of T2DM on myocardial function and its association with clinical outcomes in patients with aortic regurgitation (AR) is undetermined. The study aimed to verify whether T2DM aggravates the deterioration of myocardial deformation and clinical outcomes in AR patients. METHODS: A total of two hundred and fifty-five AR patients, differentiated by the presence or absence of T2DM [AR(T2DM+) and AR(T2DM-), respectively], along with 65 age-matched healthy individuals, underwent echocardiographic examination. Left ventricular (LV) and left atrial (LA) geometry and function, as well as LV global longitudinal strain (LVGLS) and left atrial reservoir strain (LARS), were compared among the different groups. Linear regression analyses were performed to identify the effects of T2DM on LVGLS and LARS in AR patients. In addition, major adverse cardiac events (MACEs) were recorded during follow-up. Kaplan-Meier analysis and Cox proportional hazards models were used to explore the relationship between T2DM and the risk of MACEs in AR patients. RESULTS: Compared with controls, both AR(T2DM-) and AR(T2DM+) patients exhibited significantly increased LV and LA volumes, along with reduced LV and LA ejection fractions (all P < 0.05). LVGLS and LARS progressively declined from the controls to the AR (T2DM-) group to the AR (T2DM+) group (all P < 0.05). The presence of T2DM was independently associated with impaired LVGLS and LARS in patients with AR (both P < 0.05). During a median follow-up of 29 months, 42 MACEs were recorded. The incidence of MACEs was significantly higher in patients with T2DM than in those without (30.8% vs. 11.6%; χ(2) = 20.10; P < 0.001). In multivariable analysis adjusting for clinical and echocardiographic predictors and aortic valve surgery as a time-dependent covariate, T2DM remained independently associated with MACEs (HR, 2.22; 95% CI, 1.12-4.38; P = 0.022). CONCLUSIONS: In patients with AR, T2DM exerts an additive deleterious effect on both LA and LV function and is an independent predictor of MACEs. These findings underscore the need for earlier evaluation and intervention targeting cardiac function in the context of AR complicated by T2DM.