Department of Medicine, HeartOtago, University of Otago, Dunedin, New Zealand.
School of Physical Education, Sports and Exercises Sciences, University of Otago, Dunedin, New Zealand.
Cardiovasc Diabetol. 2017 Dec 19;16(1):160. doi: 10.1186/s12933-017-0644-1.
Attenuated increases in ventricular stroke volume during exercise are common in type 2 diabetes and contribute to reduced aerobic capacity. The purpose of this study was to determine whether impaired ventricular filling or reduced systolic ejection were responsible for the attenuated stroke volume reserve in people with uncomplicated type 2 diabetes.
Peak aerobic capacity and total blood volume were measured in 17 people with diabetes and 16 non-diabetic controls with no evidence of cardiovascular disease. Left ventricular volumes and other systolic and diastolic functional parameters were measured with echocardiography at rest and during semi-recumbent cycle ergometry at 40 and 60% of maximal aerobic power and compared between groups.
People with diabetes had reduced peak aerobic capacity and heart rate reserve, and worked at lower workloads than non-diabetic controls. Cardiac output, stroke volume and ejection fraction were not different at rest, but increased less in people with diabetes during exercise. Left ventricular end systolic volume was not different between groups in any condition but end diastolic volume, although not different at rest, was smaller in people with diabetes during exercise. Total blood volume was not different between the groups, and was only moderately associated with left ventricular volumes.
People with type 2 diabetes exhibit an attenuated increase in stroke volume during exercise attributed to an inability to maintain/increase left ventricular filling volumes at higher heart rates. This study is the first to determine the role of filling in the blunted cardiac reserve in adults with type 2 diabetes.
2 型糖尿病患者在运动时心室每搏量的增加减弱较为常见，这导致其有氧能力降低。本研究旨在确定在无心血管疾病证据的单纯 2 型糖尿病患者中，是心室充盈受损还是收缩期射血减少导致了每搏量储备的减弱。
17 例糖尿病患者和 16 例非糖尿病对照者（无心血管疾病证据）进行了峰值有氧能力和总血容量测量。在休息时和半卧位踏车运动时（40%和 60%的最大有氧能力），使用超声心动图测量左心室容积和其他收缩和舒张功能参数，并在组间进行比较。
糖尿病患者的峰值有氧能力和心率储备降低，且工作负荷低于非糖尿病对照组。心输出量、每搏量和射血分数在休息时无差异，但在运动时糖尿病患者的每搏量增加较少。左心室收缩末期容积在任何情况下两组间均无差异，但舒张末期容积在休息时无差异，而在运动时糖尿病患者的舒张末期容积较小。两组间总血容量无差异，仅与左心室容积中度相关。
2 型糖尿病患者在运动时每搏量增加减弱，这归因于在较高心率时不能维持/增加左心室充盈容积。本研究首次确定了在 2 型糖尿病成人中充盈在心脏储备减弱中的作用。
