The Fontan epidemic: Population projections from the Australia and New Zealand Fontan Registry.

Background: The number and age demographic of the future Fontan population is unknown.

Methods: Population projections were calculated probabilistically using microsimulation. Mortality hazard rates for each Fontan recipient were calculated from survivorship of 1353 Fontan recipients in the Australia and New Zealand Fontan Registry, based on Fontan type, age at Fontan, gender and morphology. Projected rates of new Fontan procedures were generated from historical rates of Fontan procedures per population births.

Results: At the end of 2014, the living Fontan population of Australia and New Zealand was 1265 people from an Australian and New Zealand regional population of 28 million (4.5 per 100,000 population). Of those, 165 (13%) received an atrio-pulmonary (AP) procedure, 262 (21%) a lateral tunnel (LT) procedure and 838 (66%) an extra-cardiac conduit (ECC) procedure. This population is expected to grow to 1917 (95% CI: 1846: 1986) by 2025 (5.8 per 100,000 population), with 149 (8%) AP procedures, 254 (13%) LT procedures, and 1514 (79%) ECC procedures. By 2045, the living Fontan population is expected to reach 2986 (95% CI: 2877: 3085; 7.2 per 100,000 population). The average age of the Fontan population is expected to increase from 18years in 2014 to 23years (95% CI: 22-23) by 2025, and 31years (95% CI: 30-31) by 2045.

Conclusion: The Australian and New Zealand population of patients alive after a Fontan procedure will double over the next 20years increasing the demand for heart-failure services and cardiac transplantation. Greater consideration for the needs of this mostly adult Fontan population will be necessary.