An Undiagnosed Shone Complex in a 52-Year-Old Female: A Case Report

Shone complex (SC) is a rare congenital heart disease characterized by four obstructive anomalies, including parachute mitral valve (PMV), left atrial supra-valvular ring, subaortic stenosis, and coarctation of the aorta. Typically, SC manifests early in life. However, we encountered a 52-year-old female with a history of hypertension diagnosed at 26 years and left-sided weakness poststroke. She presented with worsening dyspnea and palpitations, prompting a thorough investigation. Echocardiography revealed a heavily calcified bicuspid aortic valve with severe aortic stenosis and parachute mitral valve with severe mitral stenosis and preserved ejection fraction, raising suspicions regarding the presence of SC. Cardiac catheterization, aortic-angiography, and noncontrast chest computed tomography (CT) revealed abrupt occlusion of the postductal aorta, giving a picture of aortic coarctation with well-established collateral vessels including prominent right and left internal mammary arteries. So, she was diagnosed with an incomplete SC at the age of 52. Shone complex is a rare congenital heart disease that typically presents in early childhood, but late presentations due to misdiagnosis or incomplete work up are possible. This case emphasizes the rarity of late presentations of SC and highlights the importance of early diagnosis and intervention to improve outcomes. An incomplete SC should be considered in adult patients presenting with left-sided obstructive lesions.