Incidentally enhancing supraclavicular lymphatic convolutes in magnetic resonance angiography in patients with Fontan circulation

PURPOSEFontan procedure and its modifications are the preferred approach to definitive palliation in uni- ventricular hearts though often with short-term or long-term complications. It is believed that a dysfunction in lymphatic circulation is responsible for part of the complications. Occasionally, abnormal supraclavicular lymphatic vessel convolutes can be observed in contrast-enhanced magnetic resonance angiography (ceMRA). This study aims to determine the frequency of this phenomenon as well as a possible correlation with the functional status after Fontan procedure.METHODSCeMRA of 37 patients after Fontan surgery was retrospectively screened and grouped for the presence or absence of abnormal lymphatic convolute. An attempt was made to identify differ- ences in the level of dysfunction of the Fontan circulation between the 2 groups.RESULTSIn 6 of 37 patients (16%), an abnormal cervical lymphatic convolute was found in the cervical venous angle. The surrogate parameters for a malfunction of the Fontan circulation did not sig- nificantly differ between both groups.CONCLUSIONThis is the first description of cervical lymphatic vessels in Fontan patients enhancing incidentally in ceMRA, probably due to venous-to-lymphatic reflux. As the likelihood of various complica- tions of Fontan circulation increases with the severity of lymphatic dysfunction, this observation could help to select patients who require closer monitoring or advanced lymphatic imaging.