冠狀動脈手術後患者運動能力與左心室舒張功能：合併糖尿病與非糖尿病患者之比較

Abstract

背景與目的：目前探討影響冠狀動脈手術後糖尿病患者運動能力因素的文獻並不多，有些研究已證實左心室舒張功能與運動能力的關係，本研究主要目的即在比較術後糖尿病與非糖尿病患者最大運動能力與左心室舒張功能之差異，並探討其之間以及和血糖、血脂的關係。方法：徵求冠狀動脈繞道手術後至少三個月、穩定無併發症患者，排除有心衰竭症狀、心瓣膜疾病、心肌梗塞、腎功能或肝功能異常、或其他系統性或急性生理異常會影響運動測試的患者。共徵得合併糖尿病組23人與對照組28人。受試者均接受非侵入性左心室功能檢查（包括心臟超音波與生物電阻心臟描計儀）、症狀限制最大運動能力測試、以及血糖與血脂分析。以SPSS 11.0統計軟體，無母數獨立樣本t檢定（Mann-Whitney U test）以及卡方檢定做各參數的組間比較，以皮爾森積差相關分析看左心室舒張功能與運動能力以及血液生化參數間的關係。定義p＜0.05為具統計上之顯著差異。結果：兩組基本資料無顯著差異，然而相較於對照組，合併糖尿病組之最大攝氧量顯著較差（p＜0.0005），心肌早期最大舒張速度（E’）與心房收縮最大速度（A’）顯著慢（p = 0.005與p = 0.030），左心室充填壓力（E/E’）則顯著較高（p = 0.004），兩組受試者之心搏量沒有顯著差異（p＞0.05）。相關性分析中，在調整年齡因素後，心房收縮充填的血流最大速度（A）以及E/E’與VO2peak呈顯著負相關（r = -0.361與r = -0.336, p < 0.05）。糖化血色素以及三酸甘油酯與最大攝氧量也有負向相關（r = -0.377, p = 0.009與r = -0.307, p = 0.028），高密度脂蛋白膽固醇則是與左心室舒張參數呈現顯著相關性。結論：冠狀動脈繞道手術後之糖尿病患者相較於非糖尿病患者，其左心室本身之順應性、左心房代償填血的能力都較差，且左心室充填壓力較高。左心室充填壓力升高與運動耐受不良有關。

Background and Purpose: The influencing factors of exercise capacity in patients after coronary artery bypass grafting (CABG), especially those with type 2 diabetes, have not been fully explored. Previous studies have demonstrated that left ventricular (LV) diastolic function correlated with exercise capacity. The purpose of this study was (1) to compare the peak exercise capacity and LV diastolic function between patients with and without diabetes and (2) to investigate the interrelations among peak oxygen consumption (VO2peak), LV diastolic function, blood sugar, and lipid profile. Methods: Fifty-one patients who underwent their first CABG more than 3 months were recruited. Those who had heart failure, valvular disease, myocardial infarction, abnormal kidney or liver function, or other systemic or acute illness that might impede the exercise testing were excluded. Twenty-three subjects were diabetes and 28 were non-diabetes. All subjects took echocardiography and impedance cardiography, graded maximal exercise test, and biochemical analyses of sugar and lipids. Nonparametric independent t-test (Mann-Whitney U test) andχ2 test were used to compare the differences between groups. The relationships between LV diastolic function, exercise capacity, and biochemical data were analyzed by Pearson product-moment correlation. A p value less than 0.05 was considered statistically significant. Results: Subjects in two groups were comparable in demographic data. Diabetic patients had lower values in early peak filling velocity (E’), peak atrial filling velocity (A’), and VO2peak (p = 0.005, p = 0.003, p<0.0005), and higher values in LV filling pressure (E/E’) (p = 0.004) than the non-diabetes. No significant difference was found in stroke volume (p > 0.05) between groups. In the results of correlation analysis, peak atrial filling flow velocity (A) and E/E’ were negatively correlated with VO2peak after age adjustments (r = -0.336, p = 0.024). Glycated hemoglobin, and triglyceride were also significantly correlated with VO2peak (r = -0.377 and r = -0.307, respectively). Only high-density lipoprotein cholesterol had significant correlation with some of LV diastolic indices. Conclusion: Diabetic patients after CABG had lower values in LV myocardial compliance and atrial compensatory filling capacity and higher values in LV filling pressure than those non-diabetic patients. The negative relationship between exercise capacity and elevated LV filling pressure was also demonstrated.