Prescription Patterns of Cardiovascular Medications in the Adolescent and Adult Population With Fontan Circulation-A Report From the Multicenter Single Ventricle Outcomes Network.

Antiplatelets and renin-angiotensin system inhibitors were the most frequently prescribed medication classes in adolescents and adults with Fontan circulation.

• Antiplatelets were prescribed to 75.6% of patients.
• Renin-angiotensin system (RAS) inhibitors were prescribed to 55.9% of patients.
• The cohort included 639 patients enrolled at 16 centers between 2022 and 2024.
• Patient age range was 13–67 years, 55.6% were male, 81.1% were White race, and 46.8% had a dominant left ventricle.

Direct oral anticoagulant (DOAC) prescriptions exceeded warfarin prescriptions in this Fontan population.

• DOACs were prescribed to 15.0% of patients.
• Warfarin was prescribed to 11.6% of patients.
• This pattern represents a notable shift given that warfarin has historically been more commonly used in Fontan patients.

Newer heart failure medications, including SGLT2 inhibitors and angiotensin receptor/neprilysin inhibitors (ARNIs), were prescribed to a small but notable minority of Fontan patients.

• SGLT2 inhibitors were prescribed to 6.3% of patients.
• Angiotensin receptor/neprilysin inhibitors (ARNIs) were prescribed to 2.2% of patients.
• These medications are primarily indicated for biventricular heart failure with reduced ejection fraction and lack supportive evidence in Fontan circulation.

Moderate or severely decreased systolic ventricular function was most strongly associated with prescription of digoxin.

• Odds ratio for digoxin prescription with moderate or severely decreased systolic ventricular function: OR 4.2 (95% CI, 2.1–8.3).
• Logistic regression was used to identify factors associated with prescribed cardiac medications.
• Ventricular function was among several clinical variables assessed.

Protein losing enteropathy (PLE) was most strongly associated with prescription of diuretics, mineralocorticoid receptor agonists, and pulmonary vasodilators.

• PLE was associated with diuretic prescription: OR 22.9 (95% CI, 8.1–64.9).
• PLE was associated with mineralocorticoid receptor agonist prescription: OR 5.3 (95% CI, 2.4–11.8).
• PLE was associated with pulmonary vasodilator prescription: OR 5.2 (95% CI, 2.5–10.8).
• These associations suggest that clinicians are using these medications to manage the hemodynamic consequences of PLE in Fontan patients.

The study population was drawn from a multicenter registry of adolescents and adults with Fontan circulation who had not undergone Fontan takedown or heart transplantation.

• 639 patients were enrolled at 16 centers in the Fontan Outcomes Network (now SV-ONE, Single Ventricle Outcomes Network) between 2022 and 2024.
• Eligible patients were 13 years of age and older.
• Patients who had undergone subsequent Fontan takedown or heart transplantation were excluded.
• This was a retrospective analysis of demographics, clinical variables, and medications prescribed.

Many medications commonly prescribed to Fontan patients are primarily indicated for biventricular heart failure with reduced ejection fraction and lack supportive evidence in the Fontan circulation.

• The authors note that RAS inhibitors, digoxin, SGLT2 inhibitors, and ARNIs are indicated for biventricular heart failure with reduced ejection fraction.
• The authors describe this as an 'absence of supportive evidence in this distinct circulation.'
• The authors call for future prospective analysis to provide insight into shifting prescribing patterns and response to therapy.