RESUMO
The crystalline selenido germanates [Li4(H2O)16][Ge4Se10]·4.3H2O (1), [{Li4(thf)12}Ge4Se10] (2), and [Li2(H2O)8][MnGe4Se10] (3) (thf = THF = tetrahydrofuran) were obtained by an extraction of a glassy ternary phase of the nominal composition Li4Ge4Se10 (=Li2S·2GeSe2) with water (1) or THF (2) and slow evaporation of the solvent or by being layered with MnBr2 in H2O/MeOH (3), respectively. The compounds contain known selenido germanate anions, however, for the first time with Li+ counterions. This is especially remarkable for the prominent ∞3{[MnGe4Se10]2-} open-framework structure, which was reported to crystallize with (NMe4)+, Cs+, Rb+, and K+ counterions, but it has not yet been realized with the smallest alkali metal cation. Impedance spectroscopic studies on Li4Ge4Se10 classify the glassy solid as a moderate Li+ ion conductor.
RESUMO
BACKGROUND: Wearable cardioverter defibrillators (WCDs) provide protection from sudden cardiac death. The efficacy of a WCD detection algorithm has not been reported outside of clinical trial. METHODS: The efficacy of the algorithm was reviewed through a retrospective analysis of appropriate shocks, inappropriate shocks, and arrhythmia detections during a 1-year period. RESULTS: WCD patients had an appropriate shock rate of 1.58 per 100 patient-months and an inappropriate shock rate of 0.99 per 100 patient-months. Most of the arrhythmia detections in a 3-month period were short in length, with only 2.7% of the detections lasting over 25 seconds, the time at which a shock becomes possible. CONCLUSIONS: By incorporating a patient responsiveness test, as well as features that eliminate or reduce signal interference common to external electrocardiogram electrodes, the WCD detection algorithm has a low risk of inappropriate shocks.
Assuntos
Algoritmos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/prevenção & controle , Cardioversão Elétrica/instrumentação , Cardioversão Elétrica/métodos , Eletrocardiografia Ambulatorial/instrumentação , Eletrocardiografia Ambulatorial/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Desenho Assistido por Computador , Diagnóstico por Computador/instrumentação , Diagnóstico por Computador/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos , Resultado do Tratamento , Adulto JovemRESUMO
In the present study, we have retrospectively analyzed the corrected QT (QTc) interval before spontaneous episodes of sudden cardiac arrest in patients with a wearable cardioverter defibrillator. Corrected QT interval was measured for all normal beats from 32 recordings of baseline rhythm and compared to normal rhythm before a paired spontaneous cardiac arrhythmia. Before arrhythmia, the QTc (505 +/- 73 ms) was not significantly longer than the baseline rhythm (497 +/- 73 ms) (P = .23). Considering ventricular tachycardia (VT) events only (12 patients), event QTc (526 +/- 75 ms) was not significantly longer than baseline QTc (520 +/- 74 ms) (P = .41). Considering fast VT/ventricular fibrillation (VF) events only (20 patients), event QTc (494 +/- 70 ms) was not significantly longer than baseline QTc (483 +/- 71 ms) (P = .26). The influence of QTc as a measure to indicate an impending VT event in a variety of VT/VF patients remains unclear.
