AbstractStructural cardiovascular alterations in the classical and hypermobile forms of Ehlers–Danlos syndrome(EDS) warrant investigation. We have examined a cohort of 38 patients with hypermobile and classical EDSs using two‐dimensional echocardiography. The cohort includes 7 males and 31 females, with an age range from 12–60 years. Altered echocardiographic parameters were seen in the initial cross‐sectional data analysis in 24/38 patients. Five of the 38 participants had mildly dilated aortic root (AR) or sinuses of Valsalva (SV), and an additional 7 patients had an abnormal pouching of the SV, although the absolute dimensions did not exceed the normal range. Ten patients had mild mitral, tricuspid, or aortic regurgitation, and only one patient had mitral valve prolapse (MVP). Three patients had low normal systolic function; three had evidence of mildly elevated pulmonary pressures, and two patients had mild concentric left ventricular hypertrophy (LVH). Five patients had evidence of impaired left ventricular relaxation (LVR) based on mitral valve E to A velocity ratio. Interestingly, 26/38 subjects demonstrated a prominent right coronary artery (RCA) easily visualized by trans‐thoracic echocardiography, and 10/38 had an elongated cardiac silhouette on the 4‐chamber apical views. The “pouching” shape of the SV was more common in hypermobile type than in the classical type of EDS. The study is ongoing and will accrue longitudinal data on 100 subjects with classical and hypermobile EDSs at 2‐year intervals. Published 2005 Wiley‐Liss, Inc.