Oral everolimus treatment in a preterm infant with multifocal inoperable cardiac rhabdomyoma associated with tuberous sclerosis complex and a structural heart defect

Rhabdomyoma (RHM) is a benign cardiac tumour usually associated with tuberous sclerosis complex (TSC). Most RHMs are asymptomatic and regress spontaneously during the first years of life. Haemodynamically significant RHMs are classically treated with surgical excision. We present a case of a premature infant, born to a mother having TSC, with a prenatal diagnosis of pulmonary valve atresia and a large ventricular septal defect. Multiple cardiac RHMs were also present, including a large tumour affecting the right ventricular filling. Owing to the prematurity and low birth weight, the infant was inoperable. In this report, we describe our approach to pharmacologically reduce the RHM size using oral everolimus in preparation for a two-ventricle surgical repair of the structural cardiac defect. We also specifically describe the dose of everolimus that was used in this case to achieve therapeutic serum levels, which was seven times lower than the conventional dose applicable for older infants.