Impact Of HbA1c On Left Ventricular Systolic Function Using SPECT in Diabetic Patients With Normal Myocardial Perfusion Imaging

Abstract

SUMMARY D iabetes mellitus, or simply diabetes, is a group of metabolic diseases in which a person has high blood sugar, either because the pancreas does not produce enough insulin, or because cells do not respond to the insulin that is produced (Dolores et al., 2011). Myocardial perfusion scan (also referred to as MPI) is a nuclear medicine procedure that evaluates many heart conditions from coronary artery disease (CAD) to hypertrophic cardiomyopathy and myocardial wall motion abnormalities. The function of the myocardium is also evaluated by calculating the left ventricular ejection fraction (LVEF) of the heart (Lee et al., 2013). It is not clear whether diabetes reduces systolic left ventricular function (left ventricular ejection fraction, LVEF) irrespective of coronary artery disease (CAD). In this study we will compare the LVEF between diabetic and non-diabetic by using SPECT (Kühne et al., 2011). The aim of our study was to to evaluate the effect of Diabetes Mellitus on ejection fraction and the impact of HbA1c on left ventricular systolic function using SPECT in diabetic patients with normal Myocardial Perfusion Imaging. Our study included 103 patients ,52 diabetics (mean age: 54.65 years; 31 male patients; 21 female patients) and 51 non diabetics (mean age: 51.18 years; 39 male patients; 12 female patients) were consecutively included into our study. The study was conducted at ALFA Scan Radiology center, Cairo, Egypt, during the period from March 2014 to August 2014. The study protocol was approved by Department of Cardiology at Ain Shams University. All patients included into the study underwent stress SPECT MPI. In comparison between diabetics and non diabetics, there was statistically significant difference found between them in age, hypertension, dyslipidemia, resting blood pressure, resting heart rate, exercise test duration and heart rate at peak exercise while there was no statistically significant difference found between them in sex, smoking, blood pressure at peak exercise, ejection fraction, end systolic volume, end diastolic volume and wall motion abnormality. In comparison between controlled and uncontrolled diabetics (according to HbA1c; ≥ 7% is considered uncontrolled), there was no statistically significant difference found between them in age, sex, hypertension, dyslipidemia, smoking, resting blood pressure, resting heart rate, exercise test duration and heart rate at peak exercise, blood pressure at peak exercise, ejection fraction, end systolic volume, end diastolic volume and wall motion abnormality. In comparison between insulin treated diabetic patients with either non insulin treated diabetic patients or non diabetic patients, there was no statistically significant difference in ejection fraction, end systolic volume and end diastolic volume