Cardiac Fibroma

Cardiac fibromas may be asymptomatic. Common presentations of cardiac fibromas include[14]:

• Heart murmurs,
• Arrhythmias,
• Congestive heart failure,
• Sudden death.

Nevoid basal cell carcinoma syndrome carries associations with lamellar or early calcification of the falx, jaw keratocysts, palmar and plantar pits, with a predisposition for basal cell carcinomas. Characteristic facial features include macrocephaly, frontal bossing, and hypertelorism. Skeletal anomalies, early childhood medulloblastoma, cleft lip/ palate, and there are reports of ovarian fibromas in female patients with NBCCS.[15] 

Imaging using magnetic resonance imaging (MRI) shows an encapsulated mass with no vascularization and delayed enhancement. Histology is not always a requirement for diagnosis in the presence of clinical phenotype and MRI findings. Electrocardiogram (ECG) in most fibroma patients shows T-wave abnormalities, and VT morphologies on ECG are mostly consistent with an origin near the tumor site. In adults, it is also reported to present as a fixed defect on myocardial perfusion imaging.[9]

Due to the rarity of cardiac fibromas (1 in 280,000 births), the best clinical management is not yet well defined, and it presents as a challenging entity for pediatric cardiologists. Suggestions for different management strategies exist in the literature including surgical resection, single ventricle palliation, cardiac transplant, and even conservative treatment with antiarrhythmic medications.

Defibrillator placement to prevent malignant arrhythmia after cardiac arrest is associated with a high risk of complications in infants and should only be considered after exploring all options with the risks and benefits explained to the parents. One of the common strategies is to place an endocardial defibrillator lead around the back of the heart in the epicardial space and use epicardial pace/sense leads. Alternatively, use epicardial pace/sense leads and tunnel an endocardial defibrillator lead along the intercostal space is also a reported option. With epicardial defibrillator, the risk of lead fracture is high with a reported 5-year failure rate of 50%.[16]

Medical management with amiodarone and beta-blockers seems to be effective. Small and apically located fibromas respond well to antiarrhythmic medications and are probably better managed without defibrillators. Surgical resection has shown to provide curative treatment, alleviating the need for a defibrillator and long-term antiarrhythmic medications. It is also a viable treatment for large fibromas with positive results. A significant hurdle is the rarity of cardiac centers with experience in removing these tumors. Optimal time reported for surgery is between 1 to 3 years. Factors like the severity of arrhythmias, medication tolerance, defibrillation lead integrity, and symptoms are often considerations and dictate the appropriate time for surgery. Location and size of the tumor can complicate surgery, but even for large fibromas operative morbidity and mortality are low. Given that there are a limited number of patients, it is difficult to test the comparative effectiveness of these treatments.[16]

In patients with tumors not amenable to resection owing to its size and extensive involvement of cardiac structures, several reported cases of “single ventricle palliation” exist. In one case with a large right ventricle fibroma, single ventricle palliation was performed by doing balloon atrial septostomy, placement of a systemic-to-pulmonary shunt to allow an unobstructed venous return to the left atrium and left ventricle to support both systemic and pulmonary circulations. This and other methods of ventricle palliation provided a bridge to heart transplantation.[17]

Differentials include cardiac rhabdomyoma, myxoma, teratoma, lipoma, and hemangioma.  

Cardiac fibromas in infancy that are not surgically resectable because of size and extensive myocardial infiltration have a poor prognosis and may require defibrillator implantation or cardiac transplantation.[18] Tumors that can are resectable (even incompletely) have a good prognosis. In one study, the median survival of patients with cardiac fibromas after successful surgery was 27 years.[19]

 If cardiac fibromas are left untreated, there is an increase in the risk of fatality, particularly due to lethal ventricular arrhythmia.

New diagnosis of NBCCS should obtain referrals to dermatologists, pediatricians, and geneticists, obstetrics-gynecology and psychology evaluations to implement cancer surveillance as per guidelines and early identification of potential complications.[8]

Because of a predisposition to basal cell carcinoma, patients with NBCCS  are encouraged to apply sunscreen, limit sun exposure, and avoid ionizing radiation.

Nevoid basal cell carcinoma syndrome, given its wide phenotypic variations, is challenging to diagnose and needs a high level of suspicion to achieve prompt and early diagnosis. In sporadic cases, diagnosing NBCCS in proband should trigger genetic testing of other family members. Once identified, management implications include appropriate cancer screening and precautions, for example, screening for basal cell carcinoma (with encouragement to apply sunscreen, limit sun exposure and avoid ionizing radiation) and early childhood medulloblastoma (children less than eight years of age are recommended to have annual brain MRI with contrast). Diagnosis of cardiac fibroma, which rarely is a presenting manifestation, should prompt an evaluation for NBCCS along with a careful assessment of the patient’s past medical and family history. 

As mentioned earlier, patients diagnosed with NBCCS are at an increased risk of benign and malignant neoplasms at an early stage. Experts have recommended coordinated multispecialty care for surveillance of NBCCS patients.[20] [V-Case series, studies with no controls and expert opinion]