Cardiac Masses - Cases

1356716 - Atrial Flutter Leading to Diagnosis of Lymphoplasmacytic Lymphoma: Power of Multimodality Imaging

Thursday, January 26, 2023

7:00 AM – 7:50 AM

Location: Pacific Jewel

Presenting Author(s)

MB

Mirza Baig, MD

Advanced Imaging Fellow
Loyola Medical Center
Oak Creek, Wisconsin, United States

Primary Author(s)

MB

Mirza Baig, MD

Advanced Imaging Fellow
Loyola Medical Center
Oak Creek, Wisconsin, United States

Co-Author(s)

MR

Mark Rabbat, MD

Associat Professor
Loyola University Medical Center, United States
MS

Mushabbar A. Syed, MD, FACC, FSCMR

Director of Cardiovascular Disease Fellowship and Cardiovascular Imaging/ Rolf & Merian Gunnar Professor of Medicine
Loyola University Medical Center
Oak Brook, Illinois, United States
Menhel Kinno, MD

Assistant Professor in Cardiology
Loyola University Medical Center
Chicago, Illinois, United States

Description of Clinical Presentation: A 77 year-old male with a history of coronary artery disease (CAD), and Waldenstrom's macroglobulinemia in remission was referred to cardiology for tachycardia, and was found to have atrial flutter. Patient had chronic bilateral lower extremity edema but otherwise asymptomatic. He underwent successful TEE guided cardioversion . Echocardiogram showed normal left ventricular (LV) function, and reduced right ventricular (RV) function with a dilated RV. As part of the ischemic work up, CT coronary angiogram was performed which showed mild non-obstructive CAD but revealed a pericardial mass along the anterior aspect of the RV free wall (Figure 1). It appeared to have a vascular supply from the right coronary artery (RCA). Cardiac magnetic resonance (CMR) was obtained for further evaluation of the mass and it was highly concerning for lymphoma based on tissue characterization (Figure 2). CMR also revealed a similar mass in the superior aspect of the interatrial septum and two separate masses in the mediastinum (Figure 2B and 2C). PET CT demonstrated an FDG avid pericardial mass with hyper metabolic mediastinal, axillary and cervical chain lymphadenopathy (Figure 3). The patient underwent bone marrow biopsy, and pathology confirmed the diagnosis of lymphoplasmacytic lymphoma

Diagnostic Techniques and Their Most Important Findings: Faced with the diagnostic challenge of a new cardiac mass found incidentally on coronary CT angiogram, CMR provided tissue characterization that accurately assessed the extent of the mass, and further identified two separate masses. CMR demonstrated a large mass attached to the anterior RV free wall within the pericardial space (which was mistakenly thought to be RV dilation on echocardiography), and two separate masses in the superior and posterior mediastinum. The pericardial mass anterior to the RV was isointense on T1 and T2 spin-echo images (Figure 2D and 2E) with no demonstration of late gadolinium enhancement (LGE) (Figure 2F and 2G), very characteristic of lymphoma. Perfusion imaging demonstrated enhancement of both masses, suggesting vascularity. The interatrial septum and two additional mediastinal masses have similar characteristics and therefore, considered to be part of the metastatic lymphoma.

Learning Points from this Case: Lymphoplasmacytic lymphoma is an uncommon mature B cell lymphoma usually involving the bone marrow and cardiac involvement is quite rare. Although echocardiography is usually the initial imaging, there are several limitations, and therefore, cardiac CT and CMR are subsequent steps for further characterization of the tumor. MRI is the best choice to accurately demonstrate the extent of myocardial and pericardial infiltration. It also helps to distinguish between benign and malignant cardiac masses emphasizing extension of infiltration, perfusion and gadolinium uptake. As demonstrated in this case, obtaining detailed non-invasive assessment suggests an advantage of multimodality imaging that can ensure efficient and effective patient management who are diagnosed with a cardiac tumor.