Rapid response of an obstructing cardiac rhabdomyoma to Sirolimus in an infant with negative genetics for Tuberosclerosis
2Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology
3Department of Pediatric, Division of Cardiology, The Hospital for Sick Children
Cardiac rhabdomyomas (cRHM) are usually associated with tuberous sclerosis complex (TSC) and are benign, often asymptomatic tumors with spontaneous regression in most cases. Less often, the patient can present with significant hemodynamic consequences and require surgery. In recent years mammalian target of rapamycin (mTOR) inhibitors were found to be an effective treatment for the manifestations of TSC, including cRHM. Most cases of cRHM treated with mTOR, were diagnosed with TSC.
We hereby present a case of cRHM in a baby with negative genetics for TSC. The cRHM caused severe right ventricle outflow (RVOT) obstruction that required surgical resection. The patient was treated with mTOR inhibitors, with reduction in RVOT gradient noted within a week. After 4 weeks of treatment the RVOT gradient decreased to mild, and the tumor circumference decreased by 50%, eliminating the need for resection. The patient needed a second course of treatment due to recurrence, also with rapid response. An Important side effect during treatment was a significant burden of premature atrial and ventricular beats that resolved at the end of treatment.
This case adds information regarding the possibility of cRHM response to mTOR inhibitors treatment in TSC negative patients, precluding the need for resection. This can be implemented for patients with cRHM who are either not diagnosed with TSC or are unstable and treatment must be started before genetic results are available.
The case was recently published in Cardiology in the young and we would like to present the clinical details along with current literature review.