Best Practice Approach for Assessment of Microchip-associated Tumors in Preclinical Safety Studies: Position of the Registry of Industrial Toxicology Animal-data (RITA).

Microchip (passive radio-frequency identification device) implantation is a common and widely employed means of animal identification in laboratory animal facilities. However, these devices have been associated with tumors of the skin and subcutis in rodents. While microchip-associated tumors are rare, they pose a challenge for accurate diagnosis and documentation in preclinical toxicity studies. Documentation of these tumors should differentiate microchip-associated lesions with spontaneously occurring or test article-induced tumors. Standardizing criteria for microchip-associated lesions will aid the diagnostic process and allow for preclinical regulatory standardization. To this end, the Registry of Industrial Toxicology Animal-data have developed clear recommendations for diagnosis and documentation of microchip-associated lesions.

Cell Damage Index as Computational Indicator for Blood Cell Activation and Damage.

Shear-induced hemolysis is a major concern in the design and optimization of blood-contacting devices. Even with a small amount of mechanical stress, inflammatory reactions can be triggered in the cells. Blood damage is typically estimated using continuum fluid dynamics simulations. In this study, we report a novel cell damage index (CDI) obtained by simulations on the single-cell level in a lattice Boltzmann fluid flow. The change of the cell surface area gives important information on mechanical stress of individual cells as well as for whole blood. We are using predefined basic channel designs to analyze and compare the newly developed CDI to the conventional blood damage calculations in very weak shear stress scenarios. The CDI can incorporate both volume fraction and channel geometry information into a single quantitative value for the characterization of flow in artificial chambers.

Hemoptysis After CardioMEMS Implantation: Case Report and Review.

BACKGROUND The CardioMEMS heart failure system is a small sensor that is placed in a branch pulmonary artery for ambulatory monitoring of pulmonary artery pressures. CardioMEMS has been approved for use in the United States in patients with New York Heart Association (NYHA) class III heart failure and frequent hospitalizations. In this report we describe a patient who had hemoptysis after CardioMEMS implantation. Further, we discuss possible etiologies for the occurrence of hemoptysis and suggest strategies to minimize this risk. CASE REPORT The patient was a 79-year-old female with NYHA class III heart failure with non-ischemic cardiomyopathy (LVEF 40%) and chronic atrial fibrillation who was referred for CardioMEMS implantation. The procedure was completed uneventfully. The patient was transferred out of the procedure suite to the recovery area where she developed a slight cough approximately 20 minutes after the implantation. Within a few coughs the patient started having hemoptysis. She was transferred to the cardiac intensive care unit for observation. She was kept off warfarin and aspirin and her hemoptysis resolved 3 days later. While the exact etiology of hemoptysis in this patient was unclear, we felt that it may have been precipitated by a minor wire-induced distal branch pulmonary artery injury. CONCLUSIONS Our report discusses hemoptysis as a potential life-threatening complication of CardioMEMS sensor implantation while suggesting possible etiologies and avoidance strategies. As the utilization of this technology expands in the years to come, a more comprehensive national registry for surveillance of device related complications will be crucial.