Comparação de desempenho entre duas gerações de eletrodos de fixação ativa com esteroides e superfície fractal / Performance comparison between two generation of active fixation leads with steroids and fractal surface / Comparación de desempeño entre dos generaciones de electrodos de fijación activa con esteroides y superficie fractal

Grande parte do sucesso e eficácia de um sistema de estimulação cardíaca artificial é, diretamente, devido a performance dos eletrodos utilizados. Os eletrodos endocárdicos são também os itens que estão mais expostos à ação deletéria do agressivo ambiente em que são instalados. Na evolução técnica desses itens, observa-se principalmente: a facilidade de uso durante o implante; a otimização dos resultados paramétricos e a busca pela máxima confiabilidade. Assim, o presente trabalho compara o desempenho de duas gerações consecutivas de eletrodos bipolares endocárdicos de fixação ativa, da empresa Biotronil GmbH: os modelos Selox SR e Setrox S. Este estudo clínico envolveu 175 Setrox S(43 VVI e 66 DDD - 66 atriais e 109 ventriculares) e 79 Selox SR (SR VVI e 22 DDD - 22 atriais e 57 eletrodos ventriculares), no período de trinta e oito meses. Além dos parâmetros elétricos dos eletrodos...

Much of the success and effectiveness of an artificial cardiac pacing system is directly due to the performance of electrodes in use. The endocardial electrodes are also items that are mostexposed to any deleterious effects from the aggressive environment in which they are installed. It is observed in the technical evolution of these items, namely: the ease of use during the implantation, the optimization of electrical parameters and search for maximum reliability. Thus, this study compares the performance of two consecutive generations of bipolar endocardial electrodes of active fixation, from the company Biotronik GmbH: the models Selox SR and Setrox S. This clinical study involving 175 Setrox S (43 VVI and 66 DDD - 66 atrial and 109 ventricular) and 79 Selox SR (35 VVI and 22 DDD - 22 atrialand 57 ventricular leads) during the thirty-eight months. In addition to the electrical parameters of electrodes...

Gran parte del éxito y la eficacia de un sistema de estimulación cardiaca artificial se debe directamente al desempeño de los electrodos utilizados. Los electrodos endocárdicos son asimismo los componentes que están más expuestos a la acción deletérea del agresivo entorno en el que se los instala.En la evolución técnica de dichos componentes se advierte especialmente: la facilidad de manejo durante el implante; la optimización de los resultados paramétricos y la búsqueda por la máxima confiabilidad. De esa manera, el presente trabajo compara el desempeño de dos generaciones consecutivas de electrodos bipolares endocárdicos de fijación activa, de la empresa Biotronik GmbH: los modelos Selox SR y SetroxS. Este estudio clínico abarcó 175 Setrox S (43 VVI y 66 DDD - 66 auriculares y 109 ventriculares) y 79Selox SR (35 VVI y 22 DDD - 22 auriculares y 57 electrodos ventriculares), en el período de treinta y ocho meses. Además de los parámetros eléctricos de los electrodos...

Doença do refluxo gastroesofágico em crianças: quão confiável é o padrão-ouro? / Gastroesophageal reflux disease in children: how reliable is the gold standard?

OBJETIVO: O monitoramento do pH esofágico é considerado o método mais confiável para diagnosticar o refluxo gastroesofágico. No entanto, a interpretação do mesmo estudo de pH pode diferir entre observadores. Neste estudo, investigamos as causas e o grau de variabilidade entre observadores. MÉTODOS: Este estudo retrospectivo incluiu todas as crianças (n = 72) que realizaram monitoramento de pH durante 1 ano no Maxima Medical Centre, em Veldhoven, Holanda. RESULTADOS: Foi encontrada uma variabilidade de 18 por cento entre observadores. A variabilidade foi causada por diferenças de opinião sobre a duração do registro, dúvidas sobre a posição da sonda, artefatos e flutuação do pH de base. CONCLUSÕES: A maioria desses problemas pode ser eliminada por avaliação da posição do eletrodo de pH e calibração pós-teste. No entanto, ainda falta uma definição clara dos artefatos de monitoramento. Este estudo mostra que a concordância mútua na interpretação dos estudos de pH foi regular (coeficiente kappa de 0,70).

OBJECTIVE: To investigate the causes and degree of interobserver variability in esophageal pH monitoring for the diagnosis of gastroesophageal reflux. METHODS: This retrospective study included all children (n = 72) who underwent pH monitoring during 1 year at Maxima Medical Centre in Veldhoven, the Netherlands. RESULTS: An interobserver variability of 18 percent was found. Variability was caused by differences in opinion about the duration of registration, doubts about probe position, artifacts and drift of baseline pH. CONCLUSIONS: Most of these problems can be eliminated by posttest calibration and assessment of the pH electrode position. However, a clear definition of monitoring artifacts is lacking. This study shows that mutual agreement in the interpretation of pH studies was fair (kappa coefficient of 0.70).

Experience in ICD implantation and follow-up in Ibn-Albitar Hospital

Survivals of sudden cardiac death [SCD] episodes have recurrence rate of 30-50% within two years, with malignant ventricular arrhythmias most often responsible. The overall survival rate for SCD in USA is 5%. Ninety-five percent of patients suffering their initial event fail to survive to become candidate for secondary prevention. Because of the wide spread acceptance of implantable cardioverter defibrillator [ICD] as a method treating the survivals of SCD, attention has turned to primary prevention. Implantable cardioverter-defibrillator [ICD] is highly effective in primary and secondary prevention of SCD due to life threatening ventricular tachycardia [VT]. To register and interpret the results of implantation and follow-up of ICD during the period between 2002-2007 in Ibn Al-Bitar hospital. Sixty patients with standard indications for ICD; data were pooled from patients history, ECG, Echocardiography, Holter, blood investigation and coronary angiography.75% males and 25% females. After implantation, class III anti-arrhythmic drugs [Amiodarone] were stopped, except for patients with a history of supraventricular tachycardia or recurrent VT. Coronary artery disease [CAD] was the most common presentation of patients for whom implantation was done; coronary artery disease [CAD] 43%, dilated cardiomyopathy [DCM] 26%, and hypertrophic obstructive cardiomyopathy [HOCM] 16%. Sixty-three of them had moderate-severe LV dysfunction [LVEF<40%]. Recurrent VT was the most common cause of implantation [76%]. Primary prevention was aimed in [60%] of patients and secondary prevention in 40%. Sixty percent of those with ICD implanted due to primary prevention fulfil MADIT II [Multicenter Automatic Defibrillator Implantation Trial II] criteria. The majority of patients had structural heart disease. Most non-sustained VTs reverted to sinus rhythm by antitachycardia pacing [ATP] therapy from ICD [90%].A11 VF events reverted to sinus rhythm by high energy shock from ICD devices. ICD is highly effective in primary and secondary prevention of life threatening VT/VF

Experiencia en el uso de un nuevo catéter electrodo de estimulación endocavitaria: Seguimiento a un año / Experience in the use of a new endocardial stimulation electrode

Background: Since February 2002, Flextend® electrode catheters are used at the Cardiovascular Unit of the Catholic University Clinical Hospital. These transvenous catheters have an IS-1 connector, silicone coating, active fixation and retractile helix with dexamethasone acetate. Aim: To report early and one year results using Flextend® catheters. Material and methods: Retrospective analysis of all patients that received an implant of a Flextend® catheter in the Unit. Results: Forty one Flextend® catheters were implanted in 24 patients, without acute displacement or clinical pericarditis. In 18 electrode catheters located in the right atrium the mean values for p wave, stimulation threshold and impedance at the moment of placement, were 2.9±1.4 mV, 0.8±0.4 V and 522±86 Ohms, respectively. The figures 24 hours after placement were 3.6±2.1 mV, 0.8±0.3 V and 612±69 Ohms, respectively. In 23 electrode catheters in the right ventricle, mean values at the moment of placement for R wave, stimulation threshold and impedance were 11.3±3.6 mV, 0.8±0.2 V and 756±108 Ohms, respectively. The figures 24 hours after placement were 3.6±2.1 mV, 0.8±0.3 V and 612±69 Ohms, respectively. In one patient, the stimulation threshold increased two months after placement and required a new intervention. Conclusions: Flextend® catheters ca be placed successfully with a low rate of complications and stable function parameters on follow up.

Effect of electrode insertion depth on word recognition in MED EL [COMBI 40+] cochlear implant users

Electrode arrays are inserted only partially into the cochlea, typically 22-30mm depending on the state of the cochlea and prosthesis type. This study aimed to investigate the effect of electrode insertion depth on world recognition in a group of 10 implanted patients using the MED-EL [COMBI 40+] multichannel cochlear implant devices, who had at least six months of "Auditory-verbal Training "experiences following implant surgery. To determine the effect of electrode insertion depth on word recognition score three different levels were simulated, including: full insertion depth [3/3], [2/3] insertion depth and 1/3 insertion depth. While the overall spectral band width was preserved, word recognition score was measured on ten disyllabic words immediately after each levels. The results showed that word recognition scores decreased dramatically by turning off the apical third of electrode array. We believe that these results indicate that: Most speech recognition could be providing by the last [Apical] third of the cochlea. 1- There are useful neurostructures for speech recognition beyond the second turn of the cochlea