Crystal-storing histiocytosis as a cause of symptomatic cardiac mass.

Crystal-storing histiocytosis is a rare disorder that is typically associated with low-grade B-cell lymphomas and monoclonal gammopathy. We present a 64-year-old man with a prior history of weakness and weight loss and hematologic evaluation that had revealed immunoglobulin G kappa monoclonal light chains in the serum and negative bone marrow biopsy. He presented with supraventricular tachyarrhythmia and a right atrial mass seen on echocardiogram and excised surgically. Histologically, the tumor was composed of sheets of macrophages infiltrating the atrial myocardium. The histiocytes were filled with multiple needle-shaped, periodic acid-Schiff-negative crystals. These cells and associated plasma cells failed to show clonal light chain restriction by in situ hybridization or immunohistochemistry, and there was no area of lymphoma in the tumor. Ultrastructural examination showed numerous stick-like, trapezoidal, or polygonal dense crystals in the cytoplasm of histiocytes corroborating the diagnosis of crystal-storing histiocytosis. Although rare, crystal-storing histiocytosis should be included in the differential diagnosis of heart masses in patients with hematologic conditions associated with monoclonal gammopathy.

Nephrotoxicity of iodixanol versus ioversol in patients with chronic kidney disease: the Visipaque Angiography/Interventions with Laboratory Outcomes in Renal Insufficiency (VALOR) Trial.

BACKGROUND: Iso-osmolar contrast medium iodixanol has been reported to be less nephrotoxic than selected low-osmolar contrast media (LOCM) in chronic kidney disease (CKD) patients with diabetes mellitus. This study compared the nephrotoxicity of iodixanol and the LOCM ioversol in CKD patients undergoing coronary angiography. METHODS: This is a prospective double-blind trial in 337 patients with stable CKD who were randomly assigned to receive the iso-osmolar contrast medium iodixanol or the LOCM ioversol. The co-primary end points were the mean peak percentage change (MPPC) in baseline serum creatinine and the incidence of contrast-induced nephropathy (rise of > 0.5 mg/dL in baseline serum creatinine within 72 hours postcontrast) for the 2 contrast media in the 72-hour period after contrast administration. Prespecified analyses included stratification on diabetic state and the use of N-acetylcysteine. RESULTS: In the 299 patients with complete post-contrast media creatinine data, the incidence of contrast-induced nephropathy was 21.8% in the iodixanol subjects and 23.8% in the ioversol subjects (P = .78). For all patients, the MPPC was 14.7% with iodixanol and 20.0% with ioversol (P = .06), whereas in the subset of diabetic patients, this value was significantly lower in the iodixanol (12.9%) compared with the ioversol subjects (22.4%, P = .01). CONCLUSIONS: Overall, the nephrotoxicity associated with iodixanol was not significantly different from that observed with ioversol in CKD patients undergoing coronary angiography, although in diabetic patients, MPPC was significantly lower in the iodixanol group.

Assessment of contemporary stent deployment using intravascular ultrasound.

Four second- and third-generation coronary stents were evaluated using QCA and intravascular ultrasound for adequacy of stent expansion, the influence of disease burden on adequacy of deployment, and postdeployment structural effects on the artery. Despite satisfactory stent deployment rates on angiography of 92 %, adequate stent deployment by IVUS ranged from 38% to 55%. There was no significant difference in deployment success across the four stent types. Lesions with significant plaque burden were associated with a lower rate of deployment success (P = 0.04). Twenty-one edge dissections were demonstrated by IVUS; only six were detected by angiography. Observations made on first-generation stents regarding adequacy of deployment still hold true for newer-generation stents. Significant plaque burden is an independent negative predictor of stent deployment success. The presence of IVUS-detected edge dissections indicates that the extent of injury during PCI extends beyond the physical length of the stent.