Invasive Hemodynamics in Asymptomatic Adult Fontan Patients and According to Different Clinical Phenotypes

BACKGROUND: The correlation between hemodynamics and clinical phenotypes/symptoms in adults post Fontan procedure has not been well studied. Moreover, the "expected" hemodynamics in those who are asymptomatic remain unclear. METHODS: This retrospective cohort included 155 adult patients post Fontan undergoing right and left cardiac catheterization between December 1999 and November 2017. Patients were categorized according to the primary indication for cardiac catheterization/clinical status, ie, fluid overload, atrial arrhythmia, exercise intolerance, abnormal liver imaging (in the absence of other indications), or asymptomatic. Underlying hemodynamics and survival were compared. RESULTS: Primary indications for cardiac catheterization were atrial arrhythmias in 49, fluid overload in 44, exercise intolerance in 37, and abnormal liver imaging in 13 patients; 12 patients were asymptomatic. The fluid overload and abnormal liver imaging groups had the highest median Fontan pressures, at 17 mm Hg (interquartile range [IQR], 14-21.8) and 17 mm Hg (IQR, 12.5-17), respectively. Among asymptomatic patients, median pulmonary artery wedge pressure was 8 mm Hg (IQR, 6-11.8) and median Fontan pressure was 13 mm Hg (IQR, 12-14.5). There was no difference in the prevalence of abnormalities of the Fontan circuit or ≥ moderate valvular regurgitation among groups. During a median follow-up of 5.3 years (IQR, 1.4-9.4), there were 48 deaths. Survival was the lowest in patients presenting with fluid overload (5-year survival, 55.6%); there were no deaths among asymptomatic patients. CONCLUSION: Asymptomatic adult Fontan patients typically have ventricular filling pressures <10 mm Hg and Fontan pressures <15 mm Hg and demonstrate excellent prognosis. Indication for catheterization predicted survival among our adult Fontan patients; the worst prognosis was noted among those presenting with fluid overload.