Table1_Abnormal left ventricular systolic reserve function detected by treadmill exercise stress echocardiography in asymptomatic type 2 diabetes.xlsx

AimsSubclinical left ventricular (LV) dysfunction may occur in T2DM patients at the early asymptomatic stage, and LV reserve function is a sensitive index to detect subtle LV dysfunction. The purpose of our study is (1) to assess the LV reserve function using treadmill exercise stress echocardiography (ESE) in asymptomatic type 2 diabetes mellitus (T2DM) patients; (2) to explore the link of serum biological parameters and LV reserve function.
MethodsThis study included 84 patients with asymptomatic T2DM from September 2021 to July 2022 and 41 sex- and age-matched healthy controls during the corresponding period. All subjects completed treadmill ESE, LV systolic function-related parameters such as global longitudinal strain (GLS) and systolic strain rate (SRs), as well as diastolic function-related parameters such as E wave (E), early diastolic velocity (e′), E/e′ ratio, early diastolic SR (SRe), and late diastolic SR (SRa) were compared at rest and immediately after exercise. The difference between LV functional parameters after treadmill exercise and its corresponding resting value was used to compute LV reserve function. In addition, the associations of LV reserve function and serum biological parameters were analyzed.
ResultsPatients with T2DM did not significantly vary from the controls in terms of alterations in LV diastolic reserve measures, the changes of LVGLS and SRs (ΔGLS: 2.19 ± 2.72% vs. 4.13 ± 2.79%, P < 0.001 and ΔSRs:0.78 ± 0.33 s−1 vs. 1.02 ± 0.28 s−1, P < 0.001) in the T2DM group were both lower than those in the control group. Glycated hemoglobin (HbA1c), N-terminal pro-brain natriuretic peptide (NTproBNP), waist circumference, and high-sensitive C-reactive protein (hsCRP) were identified as independent predictors of LV systolic reserve by stepwise multiple linear regression analysis.
ConclusionLV systolic reserve function, as measured by pre- and post-exercise differences in GLS and SRs were significantly impaired in patients with asymptomatic T2DM, whereas diastolic reserve remained normal during exercise and was comparable to that of the control group. This was different from previous findings. High levels of HbA1c, NTproBNP, hsCRP, and increasing waist circumference were independent predictors of LV systolic reserve.

研究目的：无症状早期2型糖尿病（type 2 diabetes mellitus, T2DM）患者可出现左心室亚临床功能障碍，而左心室储备功能是检测隐匿性左心室功能异常的敏感指标。本研究旨在：（1）采用跑步机运动负荷超声心动图（treadmill exercise stress echocardiography, ESE）评估无症状2型糖尿病患者的左心室储备功能；（2）探索血清生物学参数与左心室储备功能的关联。

研究方法：本研究纳入2021年9月至2022年7月期间的84例无症状2型糖尿病患者，以及同期41例性别、年龄匹配的健康对照者。所有受试者均完成跑步机运动负荷超声心动图检查，分别在静息状态及运动后即刻采集左心室收缩功能相关参数（包括整体纵向应变（global longitudinal strain, GLS）、收缩期应变率（systolic strain rate, SRs））与舒张功能相关参数（包括E峰（E wave, E）、早期舒张期速度（early diastolic velocity, e′）、E/e′比值、早期舒张期应变率（early diastolic SR, SRe）及晚期舒张期应变率（late diastolic SR, SRa））。以运动后左心室功能参数与静息状态对应参数的差值计算左心室储备功能，并分析左心室储备功能与血清生物学参数的相关性。

研究结果：2型糖尿病患者与健康对照组的左心室舒张储备指标变化无显著差异；但2型糖尿病组的左心室GLS及SRs变化量[ΔGLS：2.19±2.72% vs. 4.13±2.79%，P<0.001；ΔSRs：0.78±0.33 s⁻¹ vs. 1.02±0.28 s⁻¹，P<0.001]均显著低于对照组。经逐步多元线性回归分析显示，糖化血红蛋白（glycated hemoglobin, HbA1c）、N末端B型利钠肽原（N-terminal pro-brain natriuretic peptide, NTproBNP）、腰围及高敏C反应蛋白（high-sensitive C-reactive protein, hsCRP）为左心室收缩储备功能的独立预测因子。

研究结论：基于运动前后GLS与SRs差值计算的左心室收缩储备功能，在无症状2型糖尿病患者中显著受损，而其运动状态下的舒张储备功能仍处于正常水平，与健康对照组无显著差异，该结果与既往研究发现存在差异。高水平糖化血红蛋白、N末端B型利钠肽原、高敏C反应蛋白以及腰围增加均为左心室收缩储备功能的独立预测因子。