Quick Fire Cases
Siddarth Ragupathi, MD
Fellow
Montefiore Medical Center
Siddarth Ragupathi, MD
Fellow
Montefiore Medical Center
Safwan Gaznabi, MD
Advanced Cardiac Imaging fellow
Montefiore Medical Center, Albert Einstein College of Medicine
Daniel Lorenzatti, Sr., MD
Advanced Cardiac Imaging Cardiologist
Hospital Universitari de Vic & Montefiore Medical Center, Spain
Kristina Chae, MD
Assistant Professor
Montefiore Medical Center
Joseph Helft, MD
Assistant Professor
Montefiore Medical Center
Matthew Lazarus, MD, PhD
Assistant Professor
Montefiore Medical Center
A 29-year-old male diagnosed with past medical history of Tuberous Sclerosis (TSC) complex presented for follow-up. He had a history of cognitive impairment and seizures with neuroimaging showing multiple subependymal tubers. We present a rare case of incidentally diagnosed cardiac lipoma in a patient with tuberous sclerosis.
Diagnostic Techniques and Their Most Important Findings:
Abdominal magnetic resonance imaging (MRI) showed bilateral renal angiomyolipomas, and a small hepatic angiomyolipoma. Abdominal MRI also revealed an incidental fat intensity lesion in the right ventricle along the free wall. Cardiac MRI (CMR) further demonstrated this to be a well circumscribed non-enhancing 2 cm T1 and T2 hyperintense lesion (Figure 1 and 2), with loss of signal on T1 spectral pre-saturation with inversion recovery (SPIR) sequence (Figure 3A) and suppression on Dixon sequence (Figure 3B). This was a fully fat-containing lesion with no visualized soft-tissue component, most compatible with cardiac lipoma, a rarely reported finding in tuberous sclerosis.
Tuberous sclerosis is a neurocutaneous disorder that occurs due to TSC1 and TSC 2 gene mutations causing hamartomatous lesions with multiorgan involvement, most common manifestations being cortical or subependymal tubers, renal angiomyolipomas, and cardiac rhabdomyomas.
Cardiac lipoma is an uncommon benign neoplasm containing mature adipose tissue with no age/sex predilection. The pericardial space, right atrium, left ventricle and interatrial septum are the most common locations. However, our index case was unique by its location in the right ventricle. These lesions are usually asymptomatic, unless they have intramyocardial or intracavitary locations resulting in arrhythmias, compression of the coronary arteries or hemodynamic dysfunction. Transthoracic echocardiography (TTE) shows lipomas as hyperechoic masses owing to its fat content. However, those arising from the pericardial space appear hypoechoic for unclear reasons. In our case, TTE was non-diagnostic due to a difficult acoustic window. MRI was therefore performed to evaluate both the mass and cardiac function. While cardiac rhabdomyomas show T1 isointensity and T2 hyperintensity to adjacent myocardium, lipomas show T1 and T2 hyperintensity with fat suppression.
Learning Points from this Case:
The primary cardiac manifestation of TSC is cardiac rhabdomyoma. However, lipomas and angiomyolipomas are rarely encountered. Although angiomyolipomas should contain other components, both lesions are fat containing and cannot be reliably differentiated without histopathology. On the other hand, CMR tissue characterization alone is sufficient to distinguish rhabdomyoma from fat-containing lesions and could help avoid the need for biopsy.
