RESUMO
2013 was full of significant advances in all areas of medicine, which may have an impact on daily practice in general internal medicine. From salt and water restriction in heart failure to transfusion threshold in upper gastrointestinal bleeding and fecal infusion in Clostridium difficile colitis; from new data in resuscitation and persistent questions in palliative care and intensive care medicine, through pneumology, nephrology and endocrinology, the literature has been rich in new considerations. Each year, the residents of the Department of internal medicine of the University hospital of Vaud (CHUV) meet to share their most interesting readings. Thirteen of them are reviewed and commented here.
Assuntos
Medicina Geral/tendências , Medicina Interna/tendências , Internato e Residência , Hospitais Universitários , Humanos , SuíçaAssuntos
Fibrilação Atrial/etiologia , Bloqueio Atrioventricular/etiologia , Grupo Borrelia Burgdorferi/isolamento & purificação , Bloqueio de Ramo/etiologia , Doença de Lyme/complicações , Miocardite/complicações , Eletrocardiografia , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/diagnósticoRESUMO
UNLABELLED: L-Type Ca(2+) and K(ATP) Channels in Pacing-Induced Cardioprotection. AIMS: The L-type Ca(2+) channel, the sarcolemmal (sarcK(ATP)), and mitochondrial K(ATP) (mitoK(ATP)) channels are involved in myocardial preconditioning. We aimed at determining to what extent these channels can also participate in pacing-induced cardioprotection. METHODS: Hearts of 4-day-old chick embryos were paced in ovo during 12 hour using asynchronous intermittent ventricular stimulation at 110% of the intrinsic rate. Sham operated and paced hearts were then submitted in vitro to anoxia (30 minutes) and reoxygenation (60 minutes). These hearts were exposed to L-type Ca(2+) channel agonist Bay-K-8644 (BAY-K) or blocker verapamil, nonselective K(ATP) channel antagonist glibenclamide (GLIB), mitoK(ATP) channel agonist diazoxide (DIAZO), or antagonist 5-hydroxydecanoate. Electrocardiogram, electromechanical delay (EMD) reflecting excitation-contraction (E-C) coupling, and contractility were determined. RESULTS: Under normoxia, heart rate, QT duration, conduction, EMD, and ventricular shortening were similar in sham and paced hearts. During reoxygenation, arrhythmias ceased earlier and ventricular EMD recovered faster in paced hearts than in sham hearts. In sham hearts, BAY-K (but not verapamil), DIAZO (but not 5-hydroxydecanoate) or GLIB accelerated recovery of ventricular EMD, reproducing the pacing-induced protection. By contrast, none of these agents further ameliorated recovery of the paced hearts. CONCLUSION: The protective effect of chronic asynchronous pacing at near physiological rate on ventricular E-C coupling appears to be associated with subtle activation of L-type Ca(2+) channel, inhibition of sarcK(ATP) channel, and/or opening of mitoK(ATP) channel.