Faculty Bibliography

It is important to understand normal and abnormal radiotracer biodistribution patterns in patients who undergo cardiac Tc-2-methoxyisobutyl-isonitrile (Tc-sestamibi) scans to provide important clinical guidance. Our case describes a 75-year-old man with a history of multiple myeloma in remission, who presented to the emergency department for unrelated chest pain and shortness of breath. The patient underwent a nuclear cardiac stress test with Tc-sestamibi scintigraphy as part of his cardiac workup. The images demonstrated diffuse radiotracer uptake in the skeletal structures raising concern for progression of multiple myeloma, of which, subsequent biopsy confirmed the presence of recurrent disease.

Cardiac amyloidosis is an under-appreciated cause of heart failure. Establishing a diagnosis is important because traditional heart failure treatment regimens can worsen left ventricular failure in this disease. Endomyocardial biopsy is the gold standard for diagnosis; however, scintigraphy with radiolabeled phosphate derivatives and cardiac magnetic resonance imaging have been shown to have high sensitivity and specificity in diagnosing cardiac amyloidosis. Furthermore, cardiac scintigraphy can reliably differentiate amyloid subtypes. We present a case of transthyretin-related cardiac amyloidosis with a negative endomyocardial biopsy but positive 99m-technetium pyrophosphate single photon emission computed tomography scan and cardiac magnetic resonance imaging. We discuss the utility of 99m-technetium pyrophosphate imaging in cardiac amyloidosis and the role of single photon emission computed tomography. Finally, we review the several forms of cardiac amyloidosis and how they pertain to cardiac scintigraphy.

We present a case of a 50-year-old female with a 2-day history of back and abdominal pain who was discovered to have innumerable chronically retained acupuncture needles, which had migrated throughout her abdomen and pelvis. Although many of these needles were in precarious positions, including the epidural space, renal parenchyma, small bowel, and vasculature, there was no evidence for acute injury. We also briefly discuss evidence for the magnetic resonance imaging compatibility of acupuncture needles. Although a rare complication, given the high frequency of acupuncture therapy in the United States, physicians must be aware of the potential for retained and migrated needles.

We present a case of an intensely hypermetabolic intracavitary cardiac mass, standardized uptake values max 44.4, that was pathologically proved to be organizing and organized thrombus, negative for tumor. Our patient had previous right atrial mass resection 2 years prior that was pathologically described as either thrombus or infarcted atrial myxoma. She had since been on lifelong controlled anticoagulation; and on routine follow-up imaging, she had recurrent slow growth of a new right atrial mass. During a later hospital admission for chest pain, the mass was evaluated on both transthoracic and transesophageal echo cardiogram, which could not differentiate thrombus vs neoplasm. Cardiac magnetic resonance imaging was equivocal for mass enhancement. The patient underwent fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) evaluation, which revealed intensely hypermetabolic activity within the mass concerning for malignancy, potentially an aggressive tumor. Subsequently, the mass was surgically excised for pathological diagnosis.