Automatic Implantable Cardioverter-Defibrillator Structural Characteristics

Il existe différentes options d'appareillage et de techniques chirurgicales pour l'implantation du défibrillateur automatique. Le système peut mime être utilisé mialgré difficultés posées par la présence d'aulres appareils implantés ou par la morphologie du patient. La sensibilité ainsi que l'énergie délivrée peuvent être ajustées selon les besoins des patients. La survie de la pile est suivie de façon non-invasive, ce qui permet Ie remplacement non-urgent de l'appareil.     

Retrograde (Ventriculoatrial) Conduction in Congenital Complete Heart Block

Retrograde ventriculoatrial (VA) conduction is documented at the time of dual chamber pacemaker implantation in a 36-year-old patient with congenital complete atrioventricular (AV) block. Programmed ventricular stimulation with stimuli of increasing prematurity demonstrated a lack of decremental conduction via a unidirectional retrograde pathway. Because retrograde VA conduction has been associated with pacemaker mediated endless loop tachycardia, the status of retrograde conduction should be assessed in all patients undergoing dual chamber pacemaker implantation, including those with congenital complete AV block who have previously been considered to have no conductive tissue between atria and ventricles.     

Protein Arylation Precedes Acetaminophen Toxicity in a Dynamic Organ Slice Culture of Mouse Kidney

Acetaminophen (APAP) is an analgesic and antipyretic agent whichmay cause hepatotoxicity and nephrotoxicity with overdose inman and laboratory animals. In vivo studies suggest that insitu activation of APAP contributes to the development of nephrotoxicity.Associated with target organ toxicity is selective arylationof proteins, with a 58-kDa acetaminophen binding protein (58-ABP)being the most prominent cytosolic target. In this study a mousekidney slice model was developed to further evaluate the contributionof in situ activation of APAP to the development of nephrotoxicityand to determine the selectivity of protein arylation. Precisioncut kidney slices from male CD-1 mice were incubated with selectedconcentrations of APAP (0–25 mM) for 2 to 24 hr. APAPcaused a dose- and time-dependent decrease in nonprotein sulfhy-dryls(NPSH), ATP content, and K⁺ retention. Preceding toxicity wasarylation of cytosolic proteins, the most prominent one beingthe 58-ABP. The association of 58-ABP arylation with APAP toxicityin this mouse kidney slice model is consistent with earlier,in vivo results and demonstrates the importance of in situ activationof APAP for the development of nephrotoxicity. Precision cutrenal slices and dynamic organ culture are a good model forfurther mechanistic studies of APAP-induced renal toxicity.