A rare case of cardiac rhabdomyomas in a dizygotic twin pair

Common benign primary pediatric cardiac tumors: a primer for radiologists

Cardiac tumors are neoplasms arising from or located in the heart or the pericardium. Although rare, primary cardiac tumors in children require an accurate and timely diagnosis. Most pediatric primary cardiac tumors are benign (around 90%). Echocardiography is the first imaging modality used due to its availability, noninvasiveness, inexpensiveness, and absence of ionizing radiation. Computed tomography (CT) and magnetic resonance imaging (MRI) offer better soft tissue visualization as well as better visualization of extracardiac structures. A great advantage of MRI is the possibility of measuring cardiac function and blood flow, which can be important for obstructing cardiac tumors. In this article, we will offer a brief review of clinical, echocardiographic, CT, and MRI features of cardiac rhabdomyomas, fibromas, teratomas, and lipomas providing their differential diagnosis.

Multiple cardiac rhabdomyomas not associated with tuberous sclerosis in a dizygotic twins: a case report

Background

Rhabdomyomas comprise the majority of cardiac tumors in fetuses and are found in association with tuberous sclerosis complex. More than 90% of fetuses and neonates with multiple cardiac rhabdomyomas have signs of tuberous sclerosis complex. However, solitary cardiac rhabdomyoma cases are largely unrelated to tuberous sclerosis complex. Here, we report a case involving multiple cardiac rhabdomyomas not associated with tuberous sclerosis complex in a dizygotic twin.

Case presentation

A 36-year-old Japanese woman was diagnosed with a dizygotic twin pregnancy in the first trimester. Consistent with dizygosity, the fetal sex was discordant (male and female). At 27 weeks of gestation, hydrops and multiple echogenic cardiac masses were noted in the male baby, with the largest mass measuring 34 × 30 mm. The female fetus appeared normal. The cardiac masses enlarged gradually with the progression of the hydrops. At 32 weeks of gestation, intrauterine death of the male fetus was confirmed. The next day, autopsy of the male fetus was performed after cesarean section. Three well-demarcated white-tan-colored nodules were formed in the ventricular walls and interventricular septum, with the largest nodule (40 × 30 mm) in the left ventricular wall. Histologically, these lesions were diagnosed as rhabdomyomas.

Conclusions

We encountered a case involving multiple cardiac rhabdomyomas arising in one of dizygotic twin fetuses. Unlike most reported cases of multiple cardiac rhabdomyomas, this case was not accompanied by tuberous sclerosis complex. To the best of our knowledge, this is the first case report of multiple cardiac rhabdomyomas that developed in only one of dizygotic twins in the English literature.

A case of surgically resected cardiac rhabdomyoma with progressive left ventricular outflow tract obstruction

Cardiac rhabdomyoma is the most prevalent cardiac tumors in the pediatric population, in close association with tuberous sclerosis complex. It is usually detected antenatally or postnatally by echocardiography. Clinical presentations depend greatly on the size and position of the tumor mass. Interestingly, rhabdomyoma has a propensity to regress spontaneously and is not usually operated upon, unless the patient becomes hemodynamically compromised. Herein, we report an unusual case of surgically treated cardiac rhabdomyoma in a baby boy presented at birth with a progressive enlarging intraventricular mass, complicated with left ventricular outflow tract obstruction 7 weeks later. Histopathological examination of the intracardiac mass revealed sheets of tumor cells with spider-like morphology (known as "spider cells"), confirmed the diagnosis of rhabdomyoma. Close disease monitoring of patient's hemodynamic status in a newly diagnosed cardiac rhabdomyoma is inevitable as the tumor, although rare, may progress.

Multiple cardiac rhabdomyomas in tuberous sclerosis complex: case report and review of the literature

Cardiac rhabdomyoma is a benign tumor which constitutes the most common cardiovascular feature of the tuberous sclerosis complex, a multisystem genetically determined neurocutaneous disorder. Cardiac rhabdomyomas can be detected in the prenatal ultrasound, are usually asymptomatic and spontaneously regress within the first three years of life. Less often, the tumors' size, number, and location can produce a mass effect that may lead to blood flow abnormalities or organ dysfunction (heart failure and arrhythmia). In this setting, severe morbidity, and eventually, a lethal outcome despite clinical and surgical treatment may ensue. We describe a fatal case of multiple cardiac rhabdomyomas in a newborn girl. One of the rhabdomyomas was large and unfavorably located, causing significant obstruction of the left ventricular outflow tract. The autopsy identified, in addition to cardiac rhabdomyomas, brain glioneuronal hamartomas (cortical tubers), subependymal nodules and subependymal giant cell tumors, characteristic of the tuberous sclerosis complex. The newborn's family was investigated for the presence of typical clinical symptoms of the complex and image findings showed significant phenotypical variations and a broad symptom spectrum among the family members. This interesting case underscores the variability of tuberous sclerosis complex and the importance of performing a comprehensive postmortem examination in the identification of the cause of death, especially in the setting of familial disease.