Neurologic complications of nonbacterial thrombotic endocarditis

Endocarditis is an inflammatory or infective condition affecting the cardiac valves or endocardium, often associated with serious neurological sequelae. Nonbacterial thrombotic endocarditis (NBTE)-referred to as degenerative, Libman-Sachs, marantic, verrucous, or terminal endocarditis-is a serious but rare cause of valvular heart disease characterized by deposition of sterile vegetations of fibrin and platelet aggregates on the cardiac valves, eventually resulting in life-threatening embolization of these thrombi to the brain, limbs, or visceral organs. NBTE may complicate a heterogeneous group of chronic conditions, predominantly connective tissue and autoimmune disorders, malignancies, and diseases associated with hypercoagulability states. NBTE usually affects the native rather than prosthetic valves, and unlike infective endocarditis (IE), sparing the involved valve function without its destruction. Compared to those seen in IE, vegetations in NBTE are small and friable, thus may easily be dislodged leading to systemic thromboembolism with devastating morbidities and mortality. There are no diagnostic criteria for NBTE, and antemortem diagnosis is challenging. The condition should be suspected in patients with thromboembolic events and vegetations on the cardiac valves on echocardiographic or cardiac imaging studies, in the absence of underlying infection, especially in disorders predisposing to coagulopathy. Early recognition and prompt treatment of the primary underlying disorder is essential. Anticoagulation with heparin or heparinoid products is recommended to prevent recurrent embolism. Surgical intervention is not indicated except in selected patients with life-threatening recurrent embolism.

Morphologically proved ANCA positive Loeffler's pancarditis: medical and surgical treatment

Loeffler's endocarditis remains is a very rare disease, develops due to eosinophilic inflammation predominantly of the endocardium with an outcome in fibrosis and massive thrombus formation and. He is generally characterized by an unfavorable prognosis. Clinical case of a 42-year-old patient with Loeffler endocarditis is presented. The development of the disease was preceded by a polyvalent allergy, mild dry eye syndrome and pansinusitis with a single eosinophilia of blood up to 16%. The reason for the hospitalization was the appearance of biventricular heart failure. During the previous year, the level of blood eosinophils remained normal, a threefold increase in the level of eosinophilic cationic protein was observed once. A 20-fold increase in the pANCA level, a 2.5-fold increase in the level of antibodies to DNA, an antibody to the nuclei of cardiomyocytes 1:160 were detected. The diagnosis was made on the basis of electrocardiography data (low QRS voltage, atrial hypertrophy), echocardiography, multispiral computed tomography and magnetic resonance imaging of the heart (thickening and delayed contrasting of the endocardium, massive thrombosis of the left ventricular apex with obliteration of its cavity, encapsulated fluid in the pericardium with compression of the right ventricle). Systolic dysfunction, severe signs of restriction and arrhythmias were absent. Trombectomy, tricuspid valve plasty, pericardial resection, suturing of an open oval window were performed. Signs of active inflammation with single eosinophils, vasculitis, perimuscular sclerosis, endocardial sclerosis were detected in morphological and immunohistochemical studies of endo-, myo-, pericardium. Viral genome was not found. The therapy with methylprednisolone 24 mg/day, azathioprine 75 mg/day was started. Six months after the operation, the symptoms of heart failure are completely absent, the thrombosis did not recur.

Primary Rosai-Dorfman disease of the bone in a patient with history of breast cancer: appearance on 99mTc-MDP scintigraphy, CT, and X-ray

A 49-year-old woman with history of breast cancer presented with pain at the level of the left anterior proximal tibia. An x-ray of the tibia demonstrated a lytic cortical lesion that prompted a whole-body 99mTc-MDP bone scan. The bone scan revealed intense bone remodeling at the level of the tibial lytic lesion and in the cervical spine. CT demonstrated an expansile lesion eroding the vertebral bodies of C6 and C7 with a large soft tissue component. A biopsy of the cervical spine mass demonstrated features diagnostic of Rosai-Dorfman disease without evidence of neoplastic cells.

Dual energy computed tomography quantification of carotid plaques calcification: comparison between monochromatic and polychromatic energies with pathology correlation

PURPOSE

We compared carotid plaque calcification detection sensitivity and apparent cross-sectional area on CT as a function of CT beam energy using conventional CT techniques and virtual mono-energetic CT images generated from dual-energy acquisitions.

METHODS & MATERIALS

Five ex-vivo carotid endarterectomy (CEA) specimens were imaged with dual-energy computed tomography. Virtual monochromatic spectrum (VMS) CT images were reconstructed at energies between 40-140 keV. The same specimens were imaged using conventional polyenergetic spectrum (PS) CT with peak beam energies 80, 100, 120, and 140 kVp. The histological calcium areas on each corresponding CEA specimen were traced manually on digitized images of Toluidine-Blue/Basic-Fuchsin stained plastic sections.

RESULTS

40 keV VMS CT images provided high detection sensitivity (97 %) similar to conventional PS CT images (~96 %). The calcification size measured on CT decreased systematically with increasing CT beam energy; the rate of change was larger for the VMS images than for PS images.

CONCLUSION

From a single dual-energy CT, multiple VMS-CT images can be generated, yielding equivalent detection sensitivity and size correlations as conventional PS-CT in CEA calcification imaging. VMS-CT at 80-100 keV provided the most accurate estimates of calcification size, as compared to histology, but detection sensitivity was reduced for smaller calcifications on these images.

KEY POINTS

• Calcifications depicted at 80-100 keV were most similar to the histology standard. • Conventional polychromatic images demonstrated excellent correlation with plaque size at pathology. • Conventional polychromatic images systematically overestimate plaque size. • Plaque calcifications can be missed on high energy monochromatic images.

Cardiac MRI findings of endomyocardial fibrosis (Loeffler's endocarditis) in a patient with rheumatoid arthritis

Loeffler’s endocarditis and cardiac manifestations of the hypereosinophilic syndrome (HES) are rare and difficult to diagnose. We report a case of in a 36 year-old female with a history of rheumatoid arthritis with disabling dyspnea. The transthoracic echocardiogram demonstrated normal systolic cardiac functions and a left ventricular apical thrombus. However, using cardiovascular magnetic resonance (CMR) with inversion-recovery (IR) delayed enhancement, and cine steady-state free precession (SSFP) sequences, we were able to clearly demonstrate endocardial fibrosis, tissue inflammation, apical ventricular hypertrophy, and LV thrombus that correlate with clinical findings. We believe cardiac MRI is more useful than transthoracic echocardiography in the diagnosis and management of HES and ultimately it obviated the need for biopsy to confirm the diagnosis.

Nuclear medicine and the emergency department patient: an illustrative case-based approach

Radiologists are familiar with the use of radiographs, computed tomography, magnetic resonance imaging and ultrasound in the acute clinical setting. However, there are some specific clinical scenarios which may be found in nuclear medicine imaging problem-solving tools. These clinical scenarios and imaging techniques are less frequent, and the referring clinician from the emergency department may not consider these alternatives. It is important for the radiologist to be aware of these techniques to be able to guide the clinician to use those tools, which may result in optimal patient care. In this article, we will discuss those nuclear medicine studies which have application in the setting of an emergency radiology practice.

Multiple-gated acquisition scan with normal left ventricular ejection fraction and LBBB

Multiple-gated blood pool angiography (MUGA) using 99mTc-UltraTag (Mallinckrodt Inc., Maryland Heights, MO) labeled RBCs was performed in a patient with B-cell lymphoma for evaluation of the left ventricular ejection fraction before starting chemotherapy. Quantitative measurements from MUGA demonstrated normal left ventricular ejection fraction. However, cine images revealed delayed contraction of the left ventricle compared with that of the right, and phase contrast images demonstrated offset of the ventricles' phases. Evaluation with ECG showed delayed depolarization of the left ventricle consistent with LBBB. Phase imaging abnormalities detected on MUGA may be overlooked. Specific patterns of phase abnormalities may direct the physicians' attention toward yet unrecognized diagnoses.