The Impact of Hyperglycemia on Left Ventricular Function in Type 2 Diabetic Patients

There is an increasing recognition that diabetic patients suffer from an additional cardiac insult other than coronary artery disease termed 'diabetic cardiomyopathy' leading to 'ventricular dysfunction'. Some studies also suggested that poor glycemic control adversely affects left ventricular (LV) function. The purpose of this study was to find out the impact of glycemic control on LV function in type II diabetes mellitus patients, which may suggest possible underlying mechanisms and may be of clinical importance in planning preventive and therapeutic strategies. Methodology: The study was conducted on 100 consecutive type 2 diabetic patients of age group 40 to 65 years, admitted in SP Medical College and Associated Group of Hospitals. Ischemic Heart Disease (IHD) patients were examined clinically and 2D echocardiography was done. LV dysfunction and its severity was graded as mild, moderate and severe for systolic dysfunction and grade I, grade II, grade III, grade IV for diastolic dysfunction. All routine blood investigations, fundus examination, biothesiometry and other necessary examinations were performed. Multifactorial ANOVA test and univariate and multivariate stepwise regression analyses were used to find out association between different variables. Results: The mean values of glycated hemoglobin (HbA,C) for moderate and severe LV systolic dysfunction were 9.08% and 9.60% respectively (p<0.001). The mean values of HbA,C for grade I, grade II, grade III and grade IV were 6.72%, 7.36%, 8.70% and 9.68% respectively (p<0.001). Correlation of systolic and diastolic dysfunction with different variables shows that all the variables had highly significant differences with systolic function like BMI, duration of diabetes, serum creatinine, triglyceride, HDL, LDL, VLDL and HbA,C (p<0.001). Correlation of diastolic dysfunction with different variables also shows that BMI, LDL and HbA,C had highly significant correlation with diastolic function (p<0.001), while duration of diabetes, serum creatinine, triglyceride, total cholesterol, HDL, VLDL were significantly correlated with diastolic dysfunction (p<0.05). Conclusion: Poor glycemic control in type II diabetic patients is significantly associated with LV systolic and diastolic dysfunction. Various factors like the extent of duration of diabetes and dyslipidemia are also significantly associated with LV systolic and diastolic dysfunction in type II diabetic patients. INTRODUCTION Cardiovascular disease is responsible for 80% of deaths among diabetic patients, much of which has been attributed to coronary artery disease (CAD). However, there is an increasing recognition that diabetic patients suffer from an additional cardiac insult termed 'diabetic cardiomyopathy' leading to 'ventricular dysfunction'.' This entity was originally described in 1972 on the basis of observations in four diabetic patients who presented with heart failure (HF) without evidence of hypertension, CAD, valvular or congenital heart disease. The increasing recognition of this additional cardiac insult is supported by data from epidemiological, molecular and more refined diagnostic studies. Diabetic left ventricular (LV) dysfunction is a disorder of the cardiac muscles in people with diabetes. It can lead to inability of the heart to circulate blood through the body effectively, a state known as heart failure, leading to develop a constellation of clinical symptoms (dyspnea and fatigue) and signs (edema and rales) that lead to frequent hospitalization, a poor quality of life and a shortened life expectancy. Most heart failures in people with diabetes result from coronary artery disease, and