Sacubitril/valsartan in paediatric cardiomyopathy: a retrospective evaluation of ventricular response and clinical outcomes

Abstract Background: Sacubitril/valsartan is widely used in adults with heart failure with reduced ejection fraction, but paediatric experience, especially across ventricular dysfunction phenotypes, remains limited. Aim: To evaluate the efficacy and tolerability of sacubitril/valsartan in children with cardiomyopathy and compare outcomes in patients with predominantly right or left ventricular dysfunction. Methods: This single-centre retrospective study included 33 patients aged 1 month to 18 years who received sacubitril/valsartan between October 2020 and October 2024. Diagnoses included arrhythmogenic right ventricular cardiomyopathy, left ventricular non-compaction, and dilated cardiomyopathy. Patients were stratified by predominant ventricular dysfunction. Echocardiographic parameters, N-terminal pro B-type natriuretic peptide, six-minute walk test, NYHA class, blood pressure, creatinine, and potassium were recorded at baseline and at 1, 3, and 6 months, and at final follow-up. Clinical outcomes included rehospitalisation, death, and heart transplantation or listing. Results: The cohort included 21 male patients (63.6%), and the median age was 8.6 years. Arrhythmogenic right ventricular cardiomyopathy was present in 45.5%, left ventricular non-compaction in 15.2%, and dilated cardiomyopathy in 39.4%. Left ventricular ejection fraction >45% increased from 39.4% to 72.7%. Mean N-terminal pro B-type natriuretic peptide decreased from 6309 to 3137 pg/mL ( p < 0.001). NYHA class improved or remained stable in 93.3% of patients, with greater improvement in left ventricular dysfunction. During a median 17.3-months follow-up, rehospitalisation occurred in 42.4%, and 5 patients died or underwent heart transplantation/listing. Hypotension occurred in 18.2% but was manageable. Conclusion: Sacubitril/valsartan was generally well tolerated and associated with improved ventricular function, biomarkers, and functional status in paediatric cardiomyopathy, particularly in left ventricular dysfunction.