Though the most common method used clinically for measuring coronary blood flow velocity reserve CFVR is intracoronary Doppler flow (ICD) analysis representing the -gold-standard‖ method, we have proved that the transthoracic Doppler echocardiography (TTED) could provide noninvasive feasible and reliable data on CFVR in comparison with ICD. In earlier research we found that the CFVR reduced in about 70% patients with angiographically normal coronary arteries, which demonstrates the CFVR has particularly significance in evaluating coronary function in patients. Familial hypercholesterolemia is an autosomal dominant disorder Characterized by high serum low-density lipoprotein cholesterol concentrations. The incidence of premature coronary heart disease for familial hypercholesterolemia that without treatment is about 20-fold higher than normal people. Ischemic symptoms such as pectoris angina and myocardial infarction always occur during childhood of FH patients. Approximately 20% of heart attacks under the age of 45 are due to familial hypercholesterolemia. By measuring the CFVR, we found that the CFVR was lower in the homozygous familial hypercholesterolemia patients and CFVR have relevance with serum cholesterol concentration. We also investigate the usefulness of TTDE in coronary flow imaging (CFI) to evaluate the microvascular function in Hypertension, and found that CFVR is impaired in patients with hypertension compared with that in patients without hypertension, which proved the reduction of CFVR is a effective and noninvasive assessment parameters of microvascular function in hypertension. © 2015 Nova Science Publishers, Inc.