Minigammacámara portátil para el diagnóstico de muerte encefálica / Portable gamma-camera for the diagnosis of brain death diagnosis

Objetivo: Evaluar la factibilidad del empleo de la minigammacámara portátil Sentinella(R), para el diagnóstico de muerte encefálica (ME). Diseño: Estudio observacional, prospectivo, de factibilidad. Ámbito: Unidad de cuidados intensivos de un hospital de tercer nivel. Pacientes: Desde enero a diciembre de 2017 se registraron de forma consecutiva los pacientes mayores de edad que tras su ingreso en unidad de cuidados intensivos fueron diagnosticados de ME según criterios clínicos. Intervenciones: El procedimiento se realizó a la cabecera del paciente tras la administración intravenosa de tecnecio 99 metaestable-hexametil-propilen-amino-oxima. La ausencia de perfusión a nivel de hemisferios cerebrales y fosa posterior se describía como patrón compatible con ME. Se correlacionó el diagnóstico con doppler transcraneal y/o electroencefalograma. Resultados: Cincuenta y seis pacientes presentaron exploración física compatible con ME. Un 66,1% fueron hombres con una mediana de edad de 60 (RIQ: 51-72) años. La causa más frecuente que precipitó la ME fue el ictus hemorrágico en el 48,2% (27) seguido por traumatismo craneoencefálico grave en el 30,4% (17), ictus isquémico en el 10,7% (6) y encefalopatía anóxica tras parada cardiorrespiratoria en el 7,1% (4). En todos los casos se realizó el diagnóstico clínico de ME y posteriormente una gammagrafía portátil que confirmó dicho diagnóstico en el 100% de los pacientes. Se contrastó el resultado con doppler transcraneal en 46 de ellos que confirmaba la presencia de reverberación diastólica y/o picos sistólicos. En 10 casos se registró el electroencefalograma, con aparición de silencio eléctrico, debido a la ausencia de ventana acústica en el doppler transcraneal. Conclusiones: El uso de minigammacámara portátil puede resultar una herramienta útil y factible para el diagnóstico de ME

Objective: To evaluate the feasibility of using the Sentinella(R) portable gamma-camera for the diagnosis of brain death (BD). Design: A prospective, observational feasibility study was carried out. Setting: Intensive Care Unit of a third level hospital. Patients: Consecutive recording was made of the adults diagnosed with brain death based on clinical criteria following admission to the Intensive Care Unit in the period from January to December 2017. Interventions: The procedure was performed at the patient bedside with the intravenous administration of technetium 99 metastable hexamethylpropylene amine oxime. The absence of perfusion in the cerebral hemispheres and brainstem was described as a pattern consistent with BD. The diagnosis was correlated to the transcranial Doppler and / or electroencephalographic findings. Results: A total of 66.1% of the patients were men with an average age of 60 years [IQR: 51-72]. The most frequent causes resulting in BD were hemorrhagic stroke (48.2%, n=27), followed by traumatic brain injury (30.4%, n=17), ischemic stroke (10.7%, n=6) and post-cardiac arrest anoxic encephalopathy (7.1%, n=4). A clinical diagnosis of BD was made in all cases, and the portable gamma-camera confirmed the diagnosis in 100% of the patients with a pattern characterized by the absence of brain perfusion. In addition, the results were compared with the transcranial Doppler findings in 46 patients, confirming the presence of diastolic reverberation and / or systolic peaks. The electroencephalographic tracing was obtained in 10 cases, with the appearance of electrical silence, due to the absence of an acoustic window in the transcranial Doppler study. Conclusions: A portable gamma-camera could be a useful and feasible tool for the diagnosis of BD

Portable gamma-camera for the diagnosis of brain death diagnosis. / Minigammacámara portátil para el diagnóstico de muerte encefálica.

OBJECTIVE: To evaluate the feasibility of using the Sentinella® portable gamma-camera for the diagnosis of brain death (BD). DESIGN: A prospective, observational feasibility study was carried out. SETTING: Intensive Care Unit of a third level hospital. PATIENTS: Consecutive recording was made of the adults diagnosed with brain death based on clinical criteria following admission to the Intensive Care Unit in the period from January to December 2017. INTERVENTIONS: The procedure was performed at the patient bedside with the intravenous administration of technetium 99 metastable hexamethylpropylene amine oxime. The absence of perfusion in the cerebral hemispheres and brainstem was described as a pattern consistent with BD. The diagnosis was correlated to the transcranial Doppler and / or electroencephalographic findings. RESULTS: A total of 66.1% of the patients were men with an average age of 60 years [IQR: 51-72]. The most frequent causes resulting in BD were hemorrhagic stroke (48.2%, n=27), followed by traumatic brain injury (30.4%, n=17), ischemic stroke (10.7%, n=6) and post-cardiac arrest anoxic encephalopathy (7.1%, n=4). A clinical diagnosis of BD was made in all cases, and the portable gamma-camera confirmed the diagnosis in 100% of the patients with a pattern characterized by the absence of brain perfusion. In addition, the results were compared with the transcranial Doppler findings in 46 patients, confirming the presence of diastolic reverberation and / or systolic peaks. The electroencephalographic tracing was obtained in 10 cases, with the appearance of electrical silence, due to the absence of an acoustic window in the transcranial Doppler study. CONCLUSIONS: A portable gamma-camera could be a useful and feasible tool for the diagnosis of BD.

[Transient atrial fibrillation induced by adenosine in a patient with atrial tachycardia]. / Fibrilación auricular transitoria inducida por adenosina en una paciente con taquicardia auricular.

The administration of adenosine during atrial tachycardia usually terminates the arrhythmia or induces AV block and makes the diagnosis clear. We present a patient with atrial tachycardia in which the administration of adenosine induced a transient atrial fibrillation (AF). A continuous transition between both arrhythmias was observed and the original tachycardia persisted after the termination of the AF. This proarrhythmic effect may be due to the adenosine-mediated shortening of the atrial refractory periods, which produces a decreased wavelength of the reentry circuits and the potential coexistence of several wave-fronts in the atria, favoring the development of AF. The recognition of this uncommon effect is important, since the repeated administration of increasing doses of adenosine may induce sustained AF.

Fibrilación auricular transitoria inducida por adenosina en una paciente con taquicardia auricular / Adenosine-induced transient atrial fibrillation in a patient with atrial tachycardia

La administración de adenosina durante taquicardia auricular suele producir la terminación de la misma o aumentar el grado de bloqueo AV facilitando su diagnóstico. Presentamos un caso de inducción de fibrilación auricular (FA) transitoria por adenosina en una paciente con taquicardia auricular. La transición entre ambos ritmos fue contínua, persistiendo la taquicardia original al finalizar la FA. Este efecto proarrítmico se cree debido al acortamiento de los peridodos refractarios auriculares inducido por la adenosina, disminuyendo la longitud de onda de los circuitos de reentrada y facilitando de este modo la coexistencia simultánea de varios frentes de activación en las aurículas como ocurre en la FA.Aunque es un fenómeno poco común, su reconocimiento es importante para evitar la administración repetida de dosis crecientes de adenosina, que podría llevar a la inducción de FA sostenida (AU)

[Ventricular arrhythmias induced by appropriate antibradycardia pacing in patients with implantable defibrillators]. / Inducción de arritmias ventriculares por estimulación antibradicardia apropiada en pacientes portadores de desfibrilador automático.

INTRODUCTION AND OBJECTIVES: The induction of ventricular arrhythmias by appropriate antibradycardia ventricular pacing in patients with implantable cardioverter defibrillators has been reported in only a few cases. The aim of this study was to assess the incidence, characteristics and management of these episodes. METHODS: The follow-up records of 180 patients with implantable cardioverter defibrillators with intracardiac electrogram storage were reviewed. Pacing induced episodes were defined as those occurring immediately after an appropriate paced stimulus in a patient with sporadic paced beats. We assessed the number and type of episodes, mode of onset, therapy administered and the efficacy of different prevention measures. RESULTS: Pacing induced episodes were found in 9 patients (5%). Seven received device administered therapy which was effective in all cases. One to 95 episodes were observed per patient, of which 138 were monomorphic ventricular tachycardias and 20 polymorphic ventricular tachycardia/ventricular fibrillation episodes. All were induced by a paced ventricular beat after a post-extrasystolic pause or after long RR intervals during atrial fibrillation. Pacing induced arrhythmias were prevented by changing the pacing rate or hysteresis in 3 out of 6 patients and by decreasing the stimulus energy in 3 out of 3. Antibradycardia pacing function was disabled in 4 patients. CONCLUSIONS: Ventricular arrhythmias induced by appropriate antibradycardia ventricular pacing are relatively common in patients with implantable cardioverter defibrillators. Effective prevention can be achieved in most cases by changing the pacing rate or the pacing stimulus energy, however in selected cases the antibradycardia function may be disabled.

[Retrospective study of auricular fibrillation of recent onset in a hospital emergency service: frequency, clinical presentation, and predictive factors of early conversion to sinus rhythm]. / Estudio retrospectivo de la fibrilación auricular de reciente comienzo en un servicio de urgencias hospitalario: frecuencia, presentación clínica y factores predictivos de conversión precoz a ritmo sinusal.

AIM: To evaluate the proportion of emergencies due to recent-onset atrial fibrillation (AF), its clinical characteristics and in-hospital follow-up. The clinical predictors of conversion to sinus rhythm within the first 24 hours were analyzed. PATIENTS AND METHODS: 34,445 consecutive reports from patients presenting themselves at the emergency room of a community hospital during 15 months were retrospectively studied. The clinical reports of all patients (n = 186) with symptoms of recent onset AF (< 15 days) were reviewed. RESULTS: Hypertension (n = 77.41%) and lone AF (52 patients, 28%) were the most common etiologies. Forty seven patients (25%) presented with heart failure and the onset time was > 24 hours in 77 cases (41%). Conversion to sinus rhythm was observed in 71 out of 166 patients with at least 24 hours of follow-up (42.8%). Age < 60 years, the absence of cardiac disease, a NYHA functional class I, the absence of heart failure at the emergency room and the time from onset < 24 hours were significantly associated with conversion to sinus rhythm. The last two variables were selected as independent predictors by logistic regression analysis (sensitivity: 80%, specificity: 68%). CONCLUSIONS: We conclude that recent-onset AF represents 0.54% of all the hospital emergencies. The time from onset and the presence of heart failure predict the probability of conversion to sinus rhythm within the first 24 hours.