Evaluation hémodynamique et échographique d'une nouvelle technique de resynchronisation cardiaque par stimulation en trois sites ventriculaires

La resynchronisation cardiaque est une thérapeutique efficace permettant d'améliorer le pronostic et la qualité de vie des patients en insuffisance cardiaque réfractaire au traitement médical. Une des limites de cette thérapeutique est le taux de non-répondeurs qui varie de 15 à 30% selon les études. Afin de diminuer ce taux de non-répondeurs, nous avons proposé une nouvelle technique de resynchronisation cardiaque par stimulation en trois sites ventriculaires avec deux sites ventriculaires droits et un site ventriculaire gauche. Nous avons implanté quinze patients d'un stimulateur cardiaque avec deux sondes ventriculaires droites (une à l'apex et une au niveau septal) et une sonde ventriculaire gauche (dans le sinus coronaire) permettant trois modes de stimulation : bi ventriculaire apical, bi ventriculaire septal et tri ventriculaire (utilisant les trois sondes). Les patients ont bénéficié durant trois mois d'une resynchronisation cardiaque par trois sites ventriculaires. Pour comparer les différents modes de stimulation, nous avons évalué l'hémodynamique par impédance thoracique durant l'implantation et à trois mois, et nous avons analysé les critères échographiques de désynchronisation par échographie tridimensionnelle. Au niveau hémodynamique, le débit cardiaque par resynchronisation cardiaque tri ventriculaire (6,3+/-1,3 L/min) est significativement supérieur à la stimulation bi ventriculaire (5,6+/-1,7 L/min). Au niveau échographique, le critère de désynchronisation inter-ventriculaire n'est pas différent significativement selon le mode de stimulation. Par contre, les critères de désynchronisation infra-ventriculaire montrent une différence significative en faveur d'une amélioration par la stimulation tri ventriculaire par rapport à la stimulation bi ventriculaire.ROUEN-BU Médecine-Pharmacie (765402102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

201 Pulmonary vein isolation by cryoballoon ablation in patients with paroxysmal atrial fibrillation: efficacy, safety and predictors of arrhythmia recurrence

IntroductionRadiofrequency (RF) catheter ablation has emerged as an effective treatment for patients with drug-refractory atrial fibrillation (AF). The objective of this study is to evaluate the efficacy and safety of pulmonary vein isolation (PVI) with a cryoballoon catheter (Arctic Front, Cryocath, Quebec, Canada).MethodsIn 44 consecutive patients with symptomatic paroxysmal AF (28 males, age 57 +/− 11 years), circumferential PVI was performed using a cryoballoon catheter. Before discharge, all patients were subjected to 24-hour Holter electrocardiograms, echocardiography, and esophageal endoscopy. Magnetic resonance imaging was performed prior to and 3 months after ablation. At a mean follow up of 4.3 +/− 1.2 months after ablation, patients underwent clinical review and 24-hour Holter electrocardiograms. Clinical and demographic variables were analyzed via logistic regression to assess for predictors of recurrence.ResultsThirty-two of the 44 patients (73%) had complete isolation of all PVs. Out of 176 treated veins, 164 were completely isolated (93%). The number of balloon applications per vein was 2.3±0.8. The mean procedure and fluoroscopy times were 163.4±36.2 and 32.0±11.7min, respectively. Eight patients had evidence of mild pericardial effusions requiring no further treatment. Five patients (11.4%) experienced phrenic nerve palsy, 4 of which resolved immediately and one at 2 weeks. Follow up at 4.3 +/− 1.2 months showed freedom from AF in 28 patients (63.6%) and freedom from AF without antiarrhythmic drug therapy in 19 patients (43.2%). Of all clinical variables analyzed, only early recurrence of AF within 4 days post ablation was associated with long term AF recurrence (p=0.002; OR=0.11; CI=[0.018–0.524]).ConclusionPVI can be safely achieved with the cryoballoon catheter with a moderate success rate at 4.3 months follow-up. Early recurrence of AF seems to be a clinical predictor for long term atrial fibrillation recurrence

Histone deacetylase 6 inhibition compensates for the transport deficit in Huntington's disease by increasing tubulin acetylation.

peer reviewe

RVOT premature ventricular contractions induce significant anatomical displacement during 3D mapping: A cause of mid-term ablation failure?

International audienceBACKGROUND: Catheter ablation is a first-line treatment for symptomatic right ventricular outflow tract (RVOT) premature ventricular complexes (PVCs). There is evidence of displacement of the ablation target site during PVCs relative to the location in sinus rhythm (SR). AIM: To analyse the extent of displacement induced by RVOT PVCs and its effect on the ablation sites and the mid-term efficacy of ablation. METHODS: In this multicentre French study, we retrospectively included 18 consecutive adults referred for ablation of RVOT PVCs using a three-dimensional (3D) mapping system. PVC activation maps were performed conventionally (initial map), then each PVC activation point was manually reannotated considering the 3D location on a previous SR beat (corrected map). The ablation-site locations on the initial or the corrected area, including the 10 best activation points, were analysed. Mid-term efficacy was evaluated. RESULTS: The direction of map shift during PVCs relative to the map in SR occurred along a vertical axis in 16 of 18 patients. The mean activation-point displacement for each of the 18 mapped chambers was 5.6±2.2mm. Mid-term recurrence of RVOT PVCs occurred in 5 (28%) patients. In all patients with recurrences, no significant ablation lesion was located on the corrected (true) site of origin. CONCLUSIONS: RVOT PVCs induce a vertical anatomical shift that can mislead physicians about the true location of the arrhythmia’s site of origin. Our study highlights the association between mid-term PVC recurrence and the absence of spatial overlap between ablation points and the corrected site of origin

A dynamic unfolded protein response contributes to the control of cortical neurogenesis

peer reviewedaudience: researcher, professional, studen