Using the REtina as a Window To Detect Cardiac microvasculAR Dysfunction In Diabetes Mellitus

Diabetes is a potent risk factor for macrovascular coronary disease, leading to systolic dysfunction and heart failure. More recently diabetic microvascular disease has been recognized to play a key role in the development of diastolic dysfunction and heart failure with preserved ejection fraction. A new paradigm in diabetic heart disease centers on microvascular endothelial dysfunction involving the intra-myocardial capillaries and leading to cardiomyocyte dysfunction and diastolic dysfunction. This is analogous to the microvascular dysfunction well-described in the diabetic retinopathy and nephropathy. Yet, whereas diabetic retinal screening for retinopathy and screening for microalbuminuria are routine, diabetic cardiac screening for microvascular dysfunction is practically non-existent. The retinal vasculature may represent a window of opportunity to detect concurrent microvascular disease in the heart and kidneys before the onset of clinical symptoms. However, there are limited studies that directly attempt to correlate retinopathy to diastolic dysfunction and microalbuminuria. Hence this study aims to examine the cross-sectional relationships of retinopathy with indices of left ventricular diastolic function, coronary flow reserve and urinary albumin excretion, among diabetic patients.