Diastolic dysfunction in patients with Fontan palliation is associated with death and heart transplantation

Adults with Fontan failure (FF) have variable presentations and are often diagnosed late. Reliable predictors of FF are unknown. Diastolic dysfunction may be associated with adverse outcomes late after Fontan palliation.

Fontan patients were compared to healthy controls. FF was defined as death, transplant, diagnosis of protein-losing enteropathy, peak VO₂ <50% predicted, or new diuretic requirement. All phases in the short-axis plane were contoured to calculate filling and ejection curves. The following variables were measured by cardiovascular magnetic resonance (CMR): peak filling rate (PFR), peak ejection rate (PER), PFR and PER indexed to end diastolic volume (EDV), time to PFR (tPFR), and time to PER (tPER).

Compared to healthy controls (N=96), the Fontan group (N=98) had worse diastolic function as evidenced by decreased PFR and PFR/EDV and increased tPFR. Patients with FF (N=39) had similar ventricular systolic function and volumetrics to the Fontan subjects without failure (NF; N=59). PFR/EDV was significantly reduced, and indexed common ventricular mass was significantly higher among FF patients with the most severe adverse outcomes of death or heart transplantation. The prevalence of late gadolinium enhancement was higher in the FF cohort than the NF cohort.

CMR can identify diastolic dysfunction in the Fontan population. Patients with Fontan circulation who died or had a combined outcome of death or transplant had worse diastolic function by CMR compared to Fontan patients without death or transplant.