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Neonatal rhabdomyoma with cardiac dysfunction: favourable response to sirolimus
Menghao Duan1, Sreekanthan Sundararaghavan2, Ai Ling Koh3
1Paediatric Medicine, KK Women's and Children's Hospital, Singapore.
Insights
Sirolimus, an M-TOR inhibitor, effectively treated a newborn with a giant congenital cardiac rhabdomyoma, showing remarkable tumor regression within four months. This highlights the potential of M-TOR inhibitors in managing this rare pediatric cardiac condition.
Area of Science:
- Pediatric Cardiology
- Oncology
- Genetics
Background:
- Cardiac rhabdomyoma is the most common pediatric cardiac tumor, often linked to tuberous sclerosis complex.
- While many cases are asymptomatic, some newborns present with severe cardiac complications.
- Early intervention is crucial for reducing morbidity in affected infants.
Observation:
- A newborn diagnosed with a giant congenital cardiac rhabdomyoma experienced compromised cardiac function and myocardial ischemia.
- Echocardiography revealed significant left ventricular dyskinesia, indicating severe impairment.
Findings:
- Treatment with mammalian target of rapamycin (mTOR) inhibitors, specifically sirolimus, led to remarkable tumor regression.
- Tumor size visibly decreased within four months of sirolimus administration, as confirmed by serial echocardiography.
Implications:
- Early intervention with mTOR inhibitors can mitigate morbidity in neonates with cardiac rhabdomyoma.
- This highlights the potential of targeted therapy in managing TSC-related cardiac manifestations.
Abstract:
Cardiac rhabdomyoma is the most common cardiac tumour in childhood, with a strong genetic association to tuberous sclerosis complex. Although most of the patients remain asymptomatic, a small proportion present with cardiac complications in the early neonatal period. Timely initiation of treatment can potentially reduce disease morbidity, and mammalian target of rapamycin (M-TOR) inhibitors play an effective role in promoting regression of these tumours. A healthy term newborn was diagnosed with a giant congenital cardiac rhabdomyoma at birth. He developed clinical signs of compromised cardiac function and progressive myocardial ischaemia, with echocardiography showing significant dyskinesia. He was treated with M-TOR inhibitors and clinical response was monitored via serial echocardiography. Remarkable regression of the tumour was visibly demonstrated within 4 months of sirolimus treatment. The infant continues to be reviewed by a multidisciplinary team of physicians and monitored for features of tuberous sclerosis complex.
