Klinefelter syndrome: Cardiovascular characteristics

Patients affected by Klinefelter syndrome (KS) have higher cardiovascular mortality due to both acquired cardiovascular disease and congenital heart malformation. Metabolic syndrome and type 2 diabetes, which are highly prevalent in KS patients, may contribute to the increased cardiovascular mortality. The few available studies on cardiac damage in KS have provided conflicting results. Aside from increased prevalence of valvular abnormalities, such as mitral valve prolapses, studies have shown that KS is associated with left ventricular morpho-functional alterations. Additionally, KS is also associated with worse exercise performance, subclinical atherosclerosis, and endothelial dysfunction. A dedicated cardiovascular work-up, mainly through echocardiographic exam, has been suggested in the management of KS patients, aiming to reduce the cardiovascular risk by early diagnoses of preclinical and clinical abnormalities. More research is needed to better characterize the cardiovascular features in KS, to elucidate the pathophysiological mechanisms underlying the increased cardiovascular risk, and to define the contribution of testosterone replacement in restoring cardiovascular health in KS patients.