Marfan syndrome (MFS) is an autosomal dominant, age-related but highly penetrant condition with substantial intrafamilial and interfamilial variability. MFS is caused by pathogenetic variants in FBN1, which encodes fibrillin-1, a major structural component of the extracellular matrix that provides support to connective tissues, particularly in arteries, the pericondrium and structures in the eye. Up to 25% of individuals with MFS have de novo variants. The most prominent manifestations of MFS are asymptomatic aortic root aneurysms, aortic dissections, dislocation of the ocular lens (ectopia lentis) and skeletal abnormalities that are characterized by overgrowth of the long bones. MFS is diagnosed based on the Ghent II nosology; genetic testing confirming the presence of a FBN1 pathogenetic variant is not always required for diagnosis but can help distinguish MFS from other heritable thoracic aortic disease syndromes that can present with skeletal features similar to those in MFS. Untreated aortic root aneurysms can progress to life-threatening acute aortic dissections. Management of MFS requires medical therapy to slow the rate of growth of aneurysms and decrease the risk of dissection. Routine surveillance with imaging techniques such as transthoracic echocardiography, CT or MRI is necessary to monitor aneurysm growth and determine when to perform prophylactic repair surgery to prevent an acute aortic dissection.

马凡综合征 (MFS) 是一种常染色体显性遗传、年龄相关但具有高度外显性的疾病，具有显着的家族内和家族间变异性。MFS 是由FBN1的致病变异引起的，它编码原纤维蛋白-1，原纤维蛋白 1 是细胞外基质的主要结构成分，为结缔组织提供支持，特别是在动脉、包膜和眼睛结构中。多达 25% 的 MFS 患者有新发变异。MFS 最突出的表现是无症状的主动脉根部动脉瘤、主动脉夹层、晶状体脱位（晶状体异位）和以长骨过度生长为特征的骨骼异常。MFS 是根据 Ghent II 分类学诊断的；基因检测确认FBN1的存在致病性变异并不总是诊断所必需的，但可以帮助将 MFS 与其他可呈现与 MFS 相似的骨骼特征的遗传性胸主动脉疾病综合征区分开来。未经治疗的主动脉根部动脉瘤可发展为危及生命的急性主动脉夹层。MFS 的管理需要药物治疗来减缓动脉瘤的生长速度并降低夹层的风险。有必要使用影像技术（如经胸超声心动图、CT 或 MRI）进行常规监测，以监测动脉瘤的生长情况并确定何时进行预防性修复手术以预防急性主动脉夹层。