Heart failure in adults with congenital heart disease is a major cause of morbidity and mortality. Patients with systemic right ventricle (SRV) and single ventricle (SV) are particularly at risk1, 2, 3.

There are no specific recommendations for the management of heart failure in adults with congenital heart disease, whose management is based on "general cardiology" recommendations4,5.

Sacubitril/Valsartan is validated as a treatment for heart failure in adults with acquired pathological left ventricular dysfunction (left ventricular ejection fraction (LVEF) < 40%, New York Heart Association (NYHA) functional class II and III despite optimal heart failure therapy)7. Although this molecule is used in current practice in patients with congenital heart disease, published data are limited 6-10.

The aim of our work is to describe the efficacy and tolerability of Sacubitril/Valsartan in the treatment of chronic heart failure on VDS and VU through an observational, prospective, multicenter registry.

The latest heart failure treatment guidelines, updated in 202111, recommend the addition of type 2 sodium-glucose co-transport inhibitors in heart failure patients with impaired ejection fraction (class IA recommendation). Two molecules are used in current practice: dapagliflozin and empagliflozin, at a single dosage of 10 mg/day.

We will also be collecting data on the efficacy and safety of iSGLT2. It should be noted that, for practical reasons, there may be a delay between the end of the 1st study period (ISACC1) of one year and the start of the 2nd study period (ISACC2).

Follow-up examinations carried out during the study period will not differ from those currently recommended in current practice5.

Inclusion Criteria:

• - Patients ≥ 18 years of age
• Congenital heart disease with systemic right ventricle (D-TGV after atrial switch (Mustard or Senning surgery) or double mismatch), single ventricle of right or left morphology
• Systemic ventricular ejection fraction ≤ 40% (on cardiac magnetic resonance imaging (MRI) less than 12 months old).

In case of contraindication to MRI, LVEF ≤ 40% if systemic left ventricle or surface shortening fraction ≤ 35% if VDS12 (examination less than 12 months old).

• NYHA II or III
• On optimal heart failure therapy: ACE inhibitor or ARB2 for ≥ 4 weeks, at maximum tolerated dose. Whether or not combined with beta-blockers and maximum-tolerated-dose mineralocorticoid receptor antagonists.
• Cardiopulmonary exercise test (CPET) within the last 12 months

Exclusion Criteria:

• - Other congenital heart disease
• Inability to perform CPETH
• Immuno-allergic reaction, history of angioedema on ACE inhibitors or ARB2 inhibitors
• Symptomatic arterial hypotension or BPs < 100 mHg
• Renal insufficiency (GFR <30 mL/min/m²), hyperkalemia > 5.4 mmol/l, severe hepatic insufficiency (Child-Pugh Class C)
• Pregnancy or breast-feeding
• Opposition to use of patient data
• Type 1 diabetes if on iSGLT2

Adults with Congenital heart disease with systemic right ventricle or unique ventricle.