Case report: Loeys-Dietz syndrome (

Background: Loeys-Dietz syndrome (LDS) is a heritable aortopathy characterized by variable cardiovascular involvement, including aortic aneurysms, dissections, and congenital cardiac anomalies. Marked intrafamilial variability is a well-recognized feature, underscoring the importance of systematic assessment of at-risk relatives. Case summary: We report a family in which the index patient presented with an early ventricular septal defect and progressive aortic root dilation requiring valve-sparing surgery. MRI-based family screening identified four additional affected relatives, demonstrating a broad clinical range from asymptomatic aortic dilation to advanced disease necessitating intervention. Discussion: This case highlights the marked variability in disease expression within a single family affected by LDS and emphasizes the importance of comprehensive genetic evaluation combined with structured MRI surveillance. Such an approach enables early detection of vascular involvement and supports timely management to prevent severe complications.