& u those patients who exhibit a pseudonormal mitral inflow Doppler pattern, tissue Doppler imaging can be very valuable to establish the presence of diastolic function impairment. Furthermore, the absolute values of the mitral annular velocities by tissue Doppler echocardiography have been shown to be relatively preload independent and hence can be employed not only to assess relaxation, but also, in the context of the mitral inflow velocity data, they permit an indirect assessment of the left atrial pressure (23).

C. Myocardial Ultrasound Tissue Characterization

Ultrasound tissue characterization with backscatter analysis is a reliable method for the direct and quantitative assessment of the physical state of the myocardium. With backscatter analysis, abnormal myocardial tissue acoustic properties can be detected even in the absence of overt contractile dysfunction or alterations in chamber dimensions. Two main indices are obtained from backscatter analysis: (1) absolute integrated backscatter (analogous to the tissue echodensity) values that are linked to the structural and histological component of the myocardial tissue such as the collagen content; and (2) cyclic (systolic to diastolic) variations in integrated backscatter values that reflect myocardial contractile properties. Studies in asymptomatic type 1 diabetic patients with normal resting systolic function have demonstrated that the absolute values of integrated backscatter are increased and that the cyclic variation of tissue-integrated backscatter is blunted (24,25). These alterations of myocardial acoustic properties may be considered an early preclinical phenomenon, potentially related to collagen deposition that signals the subsequent development of diabetic cardiomyopathy, although no correlative histological or biochemical tissue assessment was carried out in these studies. Nevertheless, based on the clinical and experimental animal data available thus far, it is reasonable to state that ultrasound tissue characterization that evaluates the myocardial tissue itself can be a useful tool in the preclinical detection of diabetic cardiomyopathy in otherwise healthy and asymptomatic diabetic patients.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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