Prediction of sinus rhythm maintenance following DC-cardioversion of persistent atrial fibrillation – the role of atrial cycle length

BACKGROUND: Atrial electrical remodeling has been shown to influence the outcome the outcome following cardioversion of atrial fibrillation (AF) in experimental studies. The aim of the present study was to find out whether a non-invasively measured atrial fibrillatory cycle length, alone or in combination with other non-invasive parameters, could predict sinus rhythm maintenance after cardioversion of AF. METHODS: Dominant atrial cycle length (DACL), a previously validated non-invasive index of atrial refractoriness, was measured from lead V1 and a unipolar oesophageal lead prior to cardioversion in 37 patients with persistent AF undergoing their first cardioversion. RESULTS: 32 patients were successfully cardioverted to sinus rhythm. The mean DACL in the 22 patients who suffered recurrence of AF within 6 weeks was 152 ± 15 ms (V1) and 147 ± 14 ms (oesophagus) compared to 155 ± 17 ms (V1) and 151 ± 18 ms (oesophagus) in those maintaining sinus rhythm (NS). Left atrial diameter was 48 ± 4 mm and 44 ± 7 mm respectively (NS). The optimal parameter predicting maintenance of sinus rhythm after 6 weeks appeared to be the ratio of the lowest dominant atrial cycle length (oesophageal lead or V1) to left atrial diameter. This ratio was significantly higher in patients remaining in sinus rhythm (3.4 ± 0.6 vs. 3.1 ± 0.4 ms/mm respectively, p = 0.04). CONCLUSION: In this study neither an index of atrial refractory period nor left atrial diameter alone were predictors of AF recurrence within the 6 weeks of follow-up. The ratio of the two (combining electrophysiological and anatomical measurements) only slightly improve the identification of patients at high risk of recurrence of persistent AF. Consequently, other ways to asses electrical remodeling and / or other variables besides electrical remodeling are involved in determining the outcome following cardioversion

Implanted reuptake-deficient or wild-type dopaminergic neurons improve ON l-dopa dyskinesias without OFF-dyskinesias in a rat model of Parkinson's disease

OFF-l-dopa dyskinesias have been a surprising side-effect of intrastriatal foetal ventral mesencephalic transplantation in patients with Parkinson's disease. It has been proposed that excessive and unregulated dopaminergic stimulation of host post-synaptic striatal neurons by the grafts could be responsible for these dyskinesias. To address this issue we transplanted foetal dopaminergic neurons from mice lacking the dopamine transporter (DATKO) or from wild-type mice, into a rat model of Parkinson's disease and l-dopa-induced dyskinesias. Both wild-type and DATKO grafts reinnervated the host striatum to a similar extent, but DATKO grafts produced a greater and more diffuse increase in extra-cellular striatal dopamine levels. Interestingly, grafts containing wild-type dopaminergic neurons improved parkinsonian signs to a similar extent as DATKO grafts, but provided a more complete reduction of l-dopa induced dyskinesias. Neither DATKO nor wild-type grafts induced OFF-l-dopa dyskinesias. Behavioural and receptor autoradiography analyses demonstrated that DATKO grafts induced a greater normalization of striatal dopaminergic receptor supersensitivity than wild-type grafts. Both graft types induced a similar downregulation and normalization of PEnk and fosb/Δfosb in striatal neurons. In summary, DATKO grafts causing high and diffuse extra-cellular dompamine levels do not per se alter graft-induced recovery or produce OFF-l-dopa dyskinesias. Wild-type dopaminergic neurons appear to be the most effective neuronal type to restore function and reduce l-dopa-induced dyskinesias

Etude par conductitivité électrique d'alumines de transition dopées

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Etude de la structure et de la texture des produits de thermolyse de l'hydrargillite en vue du frittage

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Untersuchung zur körngröszen Verteilung von MgO-Kornern in gegenwart einer Flussigphase

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Effects of the oral form of ondansetron on cerebellar dysfunction. A multi-center double-blind study.

The aim of this study was to assess the efficacy and the safety of ondansetron administered orally in patients with a cerebellar disorder. The study was a randomised, multi-center, double-blind trial. The patients were randomised either to oral ondansetron 8 mg or to placebo twice daily for seven days. Cerebellar dysfunction was quantified before and after treatment using the International Cooperative Ataxia Rating Scale (ICARS). We performed a global analysis (total scores), we analysed by subscores (4 subscores: oculomotor, speech, kinetic, postural) and subgroups (4 subgroups: Cerebellar Cortical Atrophy (CCA), Multiple Systemic Atrophy (MSA), Familial Cerebellar Degeneration (FCD) and miscellaneous cerebellar disorders), and we also performed an analysis by individual test items. We investigated whether ondansetron and placebo had different effects upon ICARS total scores and subscores in the 4 subgroups considered together or separately. For p values < 0.05, we subsequently applied the Mann-Whitney test to compare ondansetron and placebo effect for each individual item. We evaluated 45 of the 46 patients included. No effect was found in global analysis. We found no difference in the analysis of the ICARS subscores. Concerning the individual test items, there was a significant difference between the placebo and ondansetron for the finger-to-nose test (p = 0.049), the Heel-to-Knee test (HK); (p = 0.03), the Body Sway Eyes Closed (p = 0.017) and the Body Sway Eyes Open (BSEO); (p = 0.014). There was no significant difference for tremor in upper limbs (p = 0.32) or for gait (p = 0.49). The Mann-Whitney test showed a greater effect of ondansetron than placebo for BSEO in miscellaneous disorders (p = 0.013) and for HK in FCD (p = 0.036), but ondansetron was deleterious for HK in CCA (p = 0.019). Our study showed no effect of oral ondansetron on global cerebellar dysfunction. The analysis by subgroups showed that the oral form of ondansetron (a) is deleterious for coordination in patients with CCA, (b) has no effect upon tremor in upper limbs, and (c) has a mild effect upon posture and coordination in lower limbs in some subgroups of ataxic diseases.Clinical TrialComparative StudyJournal ArticleMulticenter StudyRandomized Controlled TrialResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe