Marfan syndrome is an inherited connective tissue disorder with morbidity and mortality from aortic dilation and dissection. The degree of aortic dilation and response to beta-blockade (standard of care) vary in adults with Marfan syndrome. However, aortic stiffness is often present, and can be a predictor of aortic dilation and cardiovascular complications. In addition, adults with Marfan syndrome develop left ventricular diastolic dysfunction, which can progress to heart failure. Aortic stiffness and diastolic dysfunction are important and logical therapeutic targets in adults with Marfan syndrome.