Long-term milrinone therapy in children with dilated cardiomyopathy

Abstract

Aim: The aim of this study was to assess the safety and efficacy of long-term milrinone therapy in children with acute decompensated heart failure due to dilated cardiomyopathy (DCM).

Methods: A single-centre retrospective study of all children ≤18 years with acute decompensated heart failure and DCM who received continuous long-term (≥7 consecutive days) intravenous milrinone between January 2008 and January 2022.

Results: The 47 patients had a median age of 3.3 months [interquartile range (IQR) 1.0-18.1], weight of 5.7 kg [IQR 4.3-10.1] and fractional shortening of 11.9% [±4.7]. Idiopathic DCM (n = 19) and myocarditis (n = 18) were the most common diagnoses. The median milrinone infusion duration was 27 days [IQR 10-50, range 7-290]. No adverse events necessitated milrinone termination. Nine patients required mechanical circulatory support. Median follow-up was 4.2 years [IQR 2.7-8.6]. On initial admission, four patients died, six were transplanted and 79% [37/47] were discharged home. The 18 readmissions resulted in five more deaths and four transplantations. Cardiac function recovered in 60% [28/47], as measured by normalised fractional shortening.

Conclusion: Long-term intravenous milrinone is safe and effective in paediatric acute decompensated DCM. Combined with conventional heart failure therapies, it can act as a bridge to recovery and thereby potentially reduce the need for mechanical support or heart transplantation.

Keywords: cardiomyopathy; child; dilated; heart failure; milrinone; myocarditis.