Changes in pharmacotherapy in adults with Fontan circulation and associations with outcomes

There are limited data on pharmacologic management of adults living with Fontan circulation.

We planned to define changes in pharmacologic management of adults living with Fontan circulation seen at our adult congenital heart disease (ACHD) center and evaluate the association between medication changes and outcomes.

We conducted a single center retrospective study. Patient characteristics, cardiac medications, and medication start dates were abstracted by electronic medical record review. Outcomes investigated were new-onset arrhythmia, first time heart failure hospitalization, and transplant-free survival. Outcomes were compared between patients who started medications while under ACHD care with those who did not.

The most common cardiac medication class prescribed to patients prior to establishing care was angiotensin converting enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARB) (51.0%), followed by loop diuretics (28.2%) and mineralocorticoid receptor antagonists (MRA) (18.6%). There was a higher incidence of first time heart failure hospitalization and heart transplant or death in patients started on nearly all cardiac medication classes compared to those who were not. Patients started on anti-arrhythmics, loop diuretics, MRA, pulmonary vasodilators, and warfarin had the lowest 5-year transplant-free survival from medication start date.

We report commonly utilized cardiac medication classes in adults living with Fontan circulation, with our data suggesting that patients starting anti-arrhythmics, loop diuretics, MRA, pulmonary vasodilators, and warfarin may have decreased 5-year transplant-free survival from medication initiation. These medications were often started in patients with Fontan circulatory failure and/or cirrhosis, suggesting these patients constitute a sicker subset of adults living with Fontan circulation.