MR FINDINGS IN SHONES-COMPLEX OF LEFT-HEART OBSTRUCTIVE LESIONS

Background. Shone's complex is a series of four obstructive or potenti ally obstructive left-sided cardiac lesions (supravalvular mitral ring , parachute deformity of the mitral value, subaortic stenosis, and coa rctation of the aorta). Both the complete form (all four lesions) and incomplete forms (less than four lesions) have been described. Objecti ve. To determine which abnormalities of Shone's complex could be chara cterized by MR. Materials and methods. MR examinations in three patien ts (one complete, two incomplete) were retrospectively reviewed. Resul ts. A supravalvular mitral ring, found at surgery in one patient, was not identified. Regurgitant and stenotic flow across the mitral valve, abnormal motion of the valve leaflets and abnormalities of the papill ary muscles were identified. Individual chordal attachments were diffi cult to resolve. Narrowing in the subaortic region and abnormal flow f rom the subaortic region through the valve plane were demonstrated. A discrete subaortic diaphragm in one patient was not resolved. Both foc al and diffuse types of coarctation of the aorta were well characteriz ed. Conclusion. MR imaging is suited to evaluation of patients with Sh one's complex. Individual chordal attachments and thin diaphragms of t he mitral and aortic valves were difficult to resolve.