Table 1

Failing Fontan circulation

ConstitutionalGrowth failureInadequate cardiac output
Exercise intoleranceChronotropic incompetence, pronounced atrial distension
DepressionSecondary to limitations on functional status
  • Obstruction

  • Systemic venous

  • Systemic outflow

  • Atriopulmonary, pulmonary arterial

  • Pulmonary venous return, atrioventricular (AV) valve inflow

  • Ventricular outflow, aortic arch

AV valve function
  • ≥Moderate regurgitation

  • ≥Mild stenosis

Ventricular dysfunctionSecondary: atrial dilatation/distortion; AV valve or semilunar valve dysfunction, chronic arrhythmias or antiarrhythmic medications; impaired myocardial perfusion due to coronary sinus hypertension
ThrombosisSystemic venous, atrial, pulmonary
RhythmArrhythmiasSinus node dysfunction, predominant junctional rhythm, AV block, supraventricular tachycardia/atrial tachycardia, ventricular tachycardia
PulmonaryCyanosisIntracardiac right to left shunt, veno-venous collaterals, pulmonary arteriovenous malformations (AVMs)
Pleural effusions
GastrointestinalAscitesSecondary to portal hypertension related to obstruction, versus cirrhosis
MetabolicMetabolic markersDeclining albumin; thrombocytopenia; hyperbilirubinaemia; coagulopathy