Adverse remodeling of the coronary microcirculation, together with microvascular dysfunction, is a determinant of microvascular perfusion that may lead to ischemic disease and heart failure. Vessel mechanical properties such as stiffness, stress, and incremental modulus are indicators of specific heart failure/disease, but these parameters are difficult to measure directly in vivo and can be unreliable. The current “gold standard” for measuring arterial stiffness non-invasively is by pulse wave velocity, but this is largely limited to large arteries. Novel analysis of coronary flow patterns, which represents a more indicative summation of the downstream microcirculation, may be a tool to non-invasively assess microvascular remodeling and mechanics. In this study, we hypothesized that specific properties of coronary Doppler flow patterns at baseline and hyperemia correlate with remodeling and mechanical properties of the downstream coronary resistance microvessels (CRM). To test this hypothesis, 6 month old normal heterozygous Db/db and type 2 diabetic homozygous db/db mice (n=6-9 per group) underwent Doppler echocardiographical measurements of coronary flow at both baseline and hyperemia measured under 1% and 3% isoflurane, respectively. Mice were sacrificed and passive CRM structure and mechanics were assessed by pressure myography. Velocities, slopes, and times of basal and hyperemic coronary flow patterns from echocardiography were assessed as illustrated in Figure 1 and were correlated to CRM remodeling and mechanics from pressure myography. Coronary diastolic velocity of normal mice at baseline negatively correlated with incremental modulus (r=-0.756, p<0.05). Decay velocity negatively correlated with strain in normal mice at baseline (r=-0.676, p<0.05). Diastolic decay time 1 negatively correlated with internal diameter only in db/db mice at baseline (r=-0.915, p<0.05). In normal mice at hyperemia, coronary diastolic velocity and decay slope 1 were found to correlate with beta stiffness index (r=-0.883, p<0.05) and internal diameter (r=0.738, p<0.05) respectively. Diastolic rise time correlated with stress only in db/db mice under hyperemic flow (r=0.830, p<0.05). Our results indicate that strong correlations exist between Doppler flow patterns and vascular remodeling and mechanical properties such as diameter, stress, strain, incremental modulus, and beta stiffness index in normal and diabetic mice. These findings suggest that Doppler echocardiographical measurements of coronary flow at baseline and hyperemia may be a suitable non-invasive technique for assessing coronary microvascular remodeling and mechanics and may be of further use in differentiating between disease states. This may lead to a safer, less expensive, and more reliable method for predicting the onset of early coronary microvascular disease.