Background: Marfan syndrome (MFS) is a disorder of connective tissue resulting in aortic dissection or aortic aneurysm. Abnormal aortic stiffness and subclinical myocardial dysfunction has been reported in MFS, but arterial ventricular coupling (AVC) in MFS has never been investigated. The aim of this study is to investigate the relationship of aortic stiffness and AVC index in MFS using the velocity vector imaging of left ventricle (LV) and abdominal aorta. Methods: Patients who was diagnosed as MFS using Ghent nosology was included. Patients who underwent cardiovascular surgery or patients with significant valve disease more than moderate degree were excluded. Age, sex matched normal control was also included. All the study subjects underwent 2D echocardiography including velocity vector imaging of LV and abdominal aorta. Results: LV strains and strain rates were no significant difference between patients with MFS and normal control group. However, the abdominal aortic stiffness is significantly higher in patients with MFS (7.7 (4.8- 12.2) vs. 3.99 (2.9-7.7, p=0.001). AVC index was significantly increased in MFS group(0.75 짹 0.18 vs. 0.65 짹 0.09, p = 0.02; 1.69) and correlated with the abdominal aortic stiffness (r = -0.636, p < 0.001). Conclusion: Myocardial strain showed no difference between MFS and normal control, but AVC was abnormal in MFS associated with abnormal aortic stiffness. Abnormal AVC might give additive effect on myocardial performance in MFS patients.