Rapid regression of large cardiac rhabdomyomas in neonates after sirolimus therapy

Cardiac Rhabdomyomas Presenting with Critical Cardiac Obstruction in Neonates and Infants: Treatment Strategies and Outcome, A Single-Center Experience

Cardiac rhabdomyomas are the most common benign pediatric heart tumor in infancy, which are commonly associated with tuberous sclerosis complex (TSC). Most rhabdomyomas are asymptomatic and spontaneously regress over time. However, some cases especially in neonates or small infants can present with hemodynamic instability. Surgical resection of the tumor, which has been the gold standard in alleviating obstruction, is not always possible and may be associated with significant morbidity and mortality. Recently, mammalian target of rapamycin inhibitors (mTORi) have been shown to be safe and effective in the treatment of TSC. We present the outcomes of neonates and an infant who received treatment for symptomatic rhabdomyomas at a tertiary cardiology center. Medical records were reviewed to obtain clinical, demographic, and outcome data. Six patients received interventions for symptomatic rhabdomyomas, median age at presentation was 1 day old (range from 1 to 121 days old), and 67% of the patients had a pathogenic mutation in TSC gene. One patient underwent surgical resection of solitary tumor at right ventricular outflow tract (RVOT) successfully. In the four patients with left ventricular outflow tract (LVOT) obstruction, two patients received combined therapy of surgical debulking of LVOT tumor, Stage I palliation procedure, and mTORi and two patients received mTORi therapy. One patient with RVOT obstruction underwent ductal stenting and received synergistic mTORi. Four of the five patients had good response to mTORi demonstrated by the rapid regression of rhabdomyoma size. 83% of patients are still alive at their latest follow-up, at two to eight years of age. One patient died on day 17 post-LVOT tumor resection and Hybrid stage one due to failure of hemostasis, in the background of familial factor VII deficiency. Treatment of symptomatic rhabdomyoma requires individualized treatment strategy based on the underlying pathophysiology, with involvement of multidisciplinary teams. mTORi is effective and safe in inducing rapid regression of rhabdomyomas. A standardized mTORi prescription and monitoring guide will ensure medication safety in neonates and infants with symptomatic cardiac rhabdomyoma. Although the majority of tumors responded to mTORi, some prove to be resistant. Further studies are warranted, ideally involving multiple international centers with a larger number of patients.

Regression of Cardiac Rhabdomyomas Producing a Severe Aortic Stenosis: Case Report and Discussion of the Literature

We describe a case of a voluminous rhabdomyoma (R) detected by fetal echocardiography at 32 weeks' gestation (w.g.) obstructing the left ventricular inflow and aortic outflow tract, with a moderate aortic gradient at birth, not needing immediate surgery. At follow-up, the mass progressively regressed, leaving the aortic valve partly damaged, with a gradient that increased to a maximum of 100 mmHg at 9 years. The girl was then operated on successfully by a plasty of the aortic valve. The literature regarding R is discussed.

Mammalian target of rapamycin inhibitors: A new-possible approach for in-utero medication therapy

The mammalian/mechanistic target of rapamycin (mTOR) is a protein kinase that plays a crucial role in regulating cellular growth, metabolism, and survival. Although there is no absolute contraindication for the use of mTOR inhibitors during pregnancy, the specific fetal effects remain unknown. Available data from the past 2 decades have examined the use of mTOR inhibitors during pregnancy in patients with solid organ transplantation, showing no clear link to fetal complications or structural abnormalities. Recently, a handful of case reports and series have described transplacental therapy of mTOR inhibitors to control symptomatic and complicated pathologies in the fetus. The effect of these agents includes a significant reduction in lesion size in the fetus and a reduced need for mechanical ventilation in neonates. In this context, we delve into the potential of mTOR inhibitors as in-utero therapy for fetal abnormalities, with a primary focus on lymphatic malformation (LM) and cardiac rhabdomyoma (CR). While preliminary reports underscore the efficacy of mTOR inhibitors for the treatment of fetal CR and fetal brain lesions associated with tuberous sclerosis complex, chylothorax, and LMs, additional investigation and clinical trials are essential to comprehensively assess the safety and efficacy of these medications.

Congenital cardiac masses: a case report

Background

Cardiac tumors in infants and children are rare. The most common cardiac tumor is rhabdomyoma, which may be associated with tuberous sclerosis. However, not all cardiac rhabdomyomas are pathognomonic for tuberous sclerosis, and not all congenital cardiac tumors are rhabdomyomas. During the prenatal period, early cardiac tumor detection provides important information about fetal wellbeing, delivery planning, and necessary postnatal care.

Case presentation

We report a 36-year-old African American pregnant women. At 32 weeks 5 days gestational age, the male fetus had a fetal echocardiogram due to fetal arrhythmia. The fetal echocardiogram showed two small echogenic, RV apex and septal masses, suspicious of rhabdomyomas. After a routine pregnancy and a normal spontaneous vaginal delivery (39 weeks 1 day), the male baby was admitted to the neonatal intensive care unit for further monitoring and postnatal evaluation.

Conclusions

Rhabdomyomas are extremely rare and unique tumors. These tumors are very dangerous, but they usually regress after birth. During the prenatal period, early cardiac tumor detection provides important information about fetal wellbeing, delivery planning, and necessary postnatal care. We present this case to share our findings with our pediatric colleagues. Although a rarely reported case, we hope this cardiac rhabdomyoma case report and literature review can increase cardiac tumor awareness.

Neonatal rhabdomyoma with cardiac dysfunction: favourable response to sirolimus

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.

Cardiac tumours in children: a single-centre experience and literature review

Cardiac tumours are extremely rare in children. Although more than 90% are benign, children can develop obstructive or embolisation derived symptoms, arrhythmias, constitutional symptoms, cardiac tamponade, or even sudden death. Although the majority are asymptomatic, and some spontaneously regress, appropriate follow-up is needed on a case-by-case basis, as patients may develop late symptoms. Definitive diagnosis is only possible through histological analysis; however, it is possible to infer tumour type with a high grade of certainty based on imaging features, particularly cardiac magnetic resonance. Surgical resection is advocated for those causing symptoms, obstruction, cardiac dysfunction, and high risk of embolisation. The aim of this review is to present the state of the art related to cardiac tumours in the paediatric population, in the context of our own experience.

Everolimus treatment in a 3-month-old infant with tuberous sclerosis complex cardiac rhabdomyoma, severe left ventricular outflow tract obstruction, and hearing loss

Tuberous sclerosis complex is a rare multisystem genetic disorder characterised by the growth of numerous tumour-like malformations in many parts of the body including skin, kidneys, brain, lung, eyes, liver, and heart. Mutations in the TSC1 or TSC2 genes have been reported to cause disruption in the TSC1-TSC2 intracellular protein complex, causing over-activation of the mammalian target of rapamycin protein complex. In this study, we present a 3-month-old male infant diagnosed with tuberous sclerosis, bilateral neurosensorial hearing loss, Wolff-Parkinson-White syndrome on electrocardiography, multiple cardiac rhabdomyomas with severe stenosis in the left ventricular outflow tract, who responded well to the Everolimus therapy.

Treatment of Cardiac Rhabdomyomas with mTOR Inhibitors in Children with Tuberous Sclerosis Complex-A Systematic Review

BACKGROUND

Cardiac rhabdomyomas (CRs) are the earliest sign of tuberous sclerosis complex (TSC). Most of them spontaneously regress after birth. However, multiple and/or large tumors may result in heart failure or cardiac arrhythmia. Recently, the attempts to treat CRs with mTOR inhibitors (mTORi) have been undertaken. We reviewed the current data regarding the effectiveness and safety of mTORi in the treatment of CRs in children with TSC.

METHODS

The review was conducted according to the PRISMA guidelines. Medline, Embase, Cochrane library, and ClinicalTrial.gov databases were searched for original, full-text articles reporting the use of mTORi (everolimus or sirolimus) in the treatment of CRs in children with TSC.

RESULTS

Thirty articles describing 41 patients were identified (mostly case reports, no randomized or large cohort studies). Thirty-three children (80.5%) had symptomatic CRs and mTORi therapy resulted in clinical improvement in 30 of them (90.9%). CRs size reduction was reported in 95.1%. Some CRs regrew after mTORi withdrawal but usually without clinical symptoms recurrence. The observed side effects were mostly mild.

CONCLUSIONS

mTORi may be considered as a temporary and safe treatment for symptomatic CRs in children with TSC, especially in high-risk or inoperable tumors. However, high-quality, randomized trials are still lacking.

Combination percutaneous and medical management of cardiac rhabdomyomas obstructing tricuspid valve inflow: Case report

BACKGROUND

Cardiac rhabdomyomas can be prenatally diagnosed in patients with tuberous sclerosis complex. Many neonates require no intervention in early life other than close monitoring for regression of tumor over the period of months to years. In rare instances, cardiac rhabdomyomas can result in obstruction to blood flow or decreased ventricular function.

CASE REPORT

We describe the case of a neonate who was prenatally diagnosed with multiple large cardiac rhabdomyomas, one of which caused clinically significant obstruction to prograde blood flow across the tricuspid valve in the newborn period. To address the disturbance to prograde pulmonary blood flow, the patient underwent successful ductal stent placement in the neonatal period. A troponin elevation was noted shortly after birth, but no evidence of coronary compression or involvement was demonstrated by coronary angiography. The patient has subsequently been treated with sirolimus over a period of three months, with noted regression in tumors and improvement in tricuspid valve inflow.

CONCLUSIONS

A brief review of the literature regarding the diagnosis, treatment, and management of neonatal patients with cardiac rhabdomyomas is presented. A combined percutaneous and medical management approach may be of benefit in future cases of rhabdomyomas causing obstruction to pulmonary blood flow.

Literature review of international mammalian target of rapamycin inhibitor use in the non-surgical management of haemodynamically significant cardiac rhabdomyomas

Cardiac rhabdomyomas represent the most common primary paediatric cardiac tumour and typically regresses over time in the majority of patients. Among those who are symptomatic, surgical resection or catheterisation procedures have traditionally proven effective. More recently, those invasive or challenging tumours have been successfully treated with mammalian target of rapamycin inhibitors, typically everolimus and sirolimus. This review outlines the current medical literature of the state-of-the-art medical treatment of these tumours. We specifically focus on dosing regimens, duration of therapy, and side-effect profiles of mammalian target of rapamycin inhibitors among this population. Although the majority of cases responded to mammalian target of rapamycin inhibition, standardised guidelines for dosing and duration of treatment remain to be defined.

Fetal cardiac rhabdomyomas treated with maternal sirolimus

OBJECTIVE

To review the pathophysiology of rhabdomyomas and the emerging option of prenatal treatment of fetal cardiac rhabdomyomas.

METHODS

We present a case of fetal rhabdomyomas causing significant hemodynamic compromise that received in utero treatment of maternal sirolimus. Genetic amniocentesis confirmed a TSC2 mutation. A treatment program was initiated with a 10-mg loading dose titrated to a goal maternal trough of 10 to 15 ng/dL. In order to follow fetal cardiac function, a sophisticated method of speckle tracking echocardiography was used before and after treatment. Obstetric ultrasound was used to monitor fetal growth, and clinical surveillance, echocardiography, and brain MRI were used to monitor postnatal growth and development through 6 months of neonatal life.

RESULTS

Sirolimus was initiated from 28 to 36 weeks of gestation with improvement of cardiac status. During this period, intrauterine growth restriction developed. Postnatally, the infant has had stable rhabdomyomas and cardiac function without reinitiating sirolimus. Brain MRI demonstrated scattered cortical tubers and subependymal nodules, and the infant has not had seizure-like activity. At 6 months of age, the infant has achieved appropriate developmental milestones.

CONCLUSION

In counseling cases of prenatal onset large obstructing rhabdomyomas and cardiac compromise, in utero sirolimus treatment can be considered.

Clinical outcome of prenatally suspected cardiac rhabdomyomas of the fetus

Background The main objective of this retrospective analysis in a large tertiary center was the clinical outcome of prenatally diagnosed cardiac rhabdomyomas as well as the identification of factors influencing fetal prognosis. Methods A total of 45 cases of fetuses with prenatally suspected rhabdomyoma and their clinical outcome were analyzed retrospectively. A review of the literature was also performed. Results In five cases, after a tuberous sclerosis complex (TSC) mutation had been confirmed, termination of pregnancy was chosen. In 30 cases postnatal data were available. In 93% TSC was confirmed clinically or by mutational analysis. Two thirds of fetuses presented with multiple tumor while one third presented with a solitary tumor. In two fetuses mild pericardial effusions were observed. Another three fetuses presented with extrasystoles prenatally. No hydrops fetalis or fetal perinatal demise were observed. After birth 41% of the children suffered from arrhythmia including supra- and ventricular tachycardia, Wolff-Parkinson-White syndrome and atrioventricular block. One child received a Fontan procedure with Glenn anastomosis. Another child with a dilatative cardiomyopathy and a left ventricular ejection fraction of 15% died. Fifty-two percent of the children with TSC suffered from epilepsy ranging from absence epilepsy and West syndrome to generalized seizures with a frequency of up to 40 per day. Two children underwent neurosurgery to remove the epileptogenic focus. One child suffered from TSC and Lesch-Nyhan disease. In another case Beckwith-Wiedemann syndrome was identified as the causative disorder. Conclusion Rhabdomyoma are rare, benign tumors. There is an association with TSC. In the majority of cases rhabdomyoma are not hemodynamically relevant and do not increase in size. The quality of life of affected patients is impaired particularly due to epilepsy and psychomotor retardation.

A Dramatic Response to Sirolimus Therapy in a Premature Infant With Massive Cardiac Rhabdomyoma

Cardiac rhabdomyomas in neonates may cause significant cardiac risk. Recently, sirolimus has been used to treat these lesions. The dose, duration, and monitoring for therapy are unknown. A case of sirolimus use in a premature neonate is presented. No significant adverse effects were seen. Review of published cases is included. (Level of Difficulty: Advanced.)

Fetal Echocardiographic Detection of Cardiac Tumors: A Case Report of Multiple Fetal Cardiac Rhabdomyomas

Cardiac rhabdomyomas are the most common fetal cardiac tumor. They can be detected in the second and third trimesters. Rhabdomyomas are most commonly associated with the genetic disorder tuberous sclerosis complex. When associated with tuberous sclerosis complex, cardiac rhabdomyomas usually regress within the first few years of life, without complications. Symptoms depend on the size, number, and location of the rhabdomyomas. A case report of multiple cardiac rhabdomyomas that was found at 35 weeks’ gestation and is discussed.

Rapid Regression of Prenatally Identified Intrapericardial Giant Rhabdomyomas with Sirolimus

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Giant cardiac rhabdomyomas were identified on fetal echocardiography.

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The rhabdomyomas were unusually located in the pericardial space.

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Rapid regression and hemodynamic improvement were seen with sirolimus therapy.

Giant left ventricular rhabdomyoma treated successfully with everolimus: case report and review of literature

IntroductionIntracardiac rhabdomyomas can cause severe ventricular dysfunction and outflow tract obstruction.Case reportA term newborn infant with antenatal diagnosis of giant left ventricle rhabdomyoma presented with cardiac failure and duct-dependent systemic circulation after birth. She was treated successfully with everolimus, showing decrease in tumour size and improvement in left ventricular ejection fraction.DiscussionTumour regression rate was 0.32 cm2/day and improved to 0.80 cm2/day with the use of everolimus. Herein we report a newborn with inoperable giant left ventricular cardiac rhabdomyoma and significant regression of the tumour. To our knowledge, this is the largest left ventricular rhabdomyoma reported. A review of the literature was undertaken for comparison.

CONCLUSION

Everolimus has proven to be efficacious in size reduction of cardiac rhabdomyomas in cases when surgical resection is not possible.

Sirolimus in Infants with Multiple Cardiac Rhabdomyomas Associated with Tuberous Sclerosis Complex

INTRODUCTION

Cardiac rhabdomyomas represent a frequent manifestation of tuberous sclerosis. Tumor growth, mainly prenatally, can result in intrauterine fetal or neonatal deaths in almost 10% of patients.

CASE REPORT

We treated 3 consecutive infants aged less than 12 months with sirolimus, an oral mTOR inhibitor. All patients achieved significant reductions in cardiac rhabdomyomas. A complete response was documented in 2 patients, while a partial response with tumor debulking greater than 50% was seen in the other one. The median time to best cardiac response was 1.9 months in all patients, and 3.3 months in those with complete response. The side effects profile was acceptable.

CONCLUSION

Sirolimus may have a significant role in promoting natural regression of cardiac rhabdomyomas. Prospective clinical trials are needed.