Left Ventricular Pacing In Patients With Congestive Heart Failure

Cardiac resynchronisation therapy (CRT) using biventricular (BIV) pacing has proved its effectiveness to correct myocardial asynchrony and improve clinical status of patients with severe congestive heart failure (CHF) and widened QRS. Despite a different effect on left ventricular electrical dispersion, left univentricular (LV) pacing is able to achieve the same mechanical synchronisation as BIV pacing in experimental studies and in humans. This results in clinical benefits of LV pacing at mid-term follow-up, with significant improvement in functional class, quality of life and exercise tolerance at the same extent as those observed with BIV stimulation in non randomised studies. Furthermore these benefits are obtained at lesser costs and with conventional dual-chamber devices. However, LV pacing has to be compared to BIV pacing in randomised trials before being definitely considered as a cost-effective alternative to BIV pacing

The Use of Epicardial Electrogram as a Simple Guide to Select the Optimal Site of Left Ventricular Pacing in Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT) has been demonstrated to improve symptoms and survival in patients with left ventricular (LV) systolic dysfunction and dyssynchrony. To achieve this goal, the LV lead should be positioned in a region of delayed contraction. We hypothesized that pacing at the site of late electrical activation was also associated with long-term response to CRT. We conducted a retrospective study on 72 CRT patients. For each patient, we determined the electrical delay (ED) from the onset of QRS to the epicardial EGM and the ratio of ED to QRS duration (ED/QRS duration). After a followup of 30 ± 20 months, 47 patients responded to CRT. Responders had a significantly longer ED and greater ratio of ED/QRS duration than nonresponders. An ED/QRS duration ≥0.38 predicted a response to CRT with 89% specificity and 53% sensitivity

Gated blood-pool SPECT evaluation of changes after radiofrequency catheter ablation of accessory pathways Evidence for persistent ventricular preexcitation despite successful therapy

AbstractOBJECTIVESThis study was designed to prospectively evaluate the effects of radiofrequency ablation in Wolff-Parkinson-White (WPW) syndrome by scintigraphic analysis.BACKGROUNDThe functional changes triggered by radiofrequency current ablation of atrioventricular accessory pathways are not fully known.METHODSForty-four patients with WPW syndrome were consecutively investigated before and 48 h after radiofrequency therapy. Fourteen patients had right sided atrioventricular pathways and 30 patients had left sided bypass-tracts. Planar gated imaging and gated blood pool tomography were performed in all of these patients.RESULTSA significant increase in the left ventricular ejection fraction (LVEF) was demonstrated in patients with left preexcitation (62.2 ± 7.9% before ablation against 64.4 ± 6.3% after ablation, p = 0.02) but not for those with right sided anomalous pathway. Phase analysis only gave significant differences following ablation of right sided pathways (left-to-right phase difference = 14.4 ± 13.8° before ablation versus 7.5 ± 7.2° after ablation, p < 0.05). Early abnormal ventricular contraction persisted in 12 patients with right accessory pathways and in 8 patients with left accessory pathways despite the complete disappearance of any abnormal conduction as proven electrophysiologically.CONCLUSIONSFollowing catheter ablation of atrioventricular accessory pathways: 1) an improvement of left ventricular function may be seen, particularly in patients with left sided accessory pathways, and 2) unexpected persistence of local ventricular preexcitation at the site of successful ablation may be detected

Insuffisance cardiaque traitée par resynchronisation (facteurs prédictifs de mortalité, impact de la fibrillation atriale sur le pronostic, incidence de la fibrillation atriale)

BREST-BU Médecine-Odontologie (290192102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Valeur du bloc isthmique obtenu sous imprégnation antiarythmique pour la prédiction de récidive du flutter atrial isthme-dépendant

BREST-BU Médecine-Odontologie (290192102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Flutter auriculaire après chirurgie cardiaque (facteur prédictifs et pronostic à long terme)

BREST-BU Médecine-Odontologie (290192102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Influence du site de stimulation ventriculaire droite sur la mortalité, la survenue d'insuffisance cardiaque et d'arythmies auriculaires à long terme

Classiquement, la stimulation ventriculaire droite s'effectue par implantation d'une sonde ventriculaire par voie veineuse sous-clavière ou céphalique à l'apex du ventricule droit. Les conséquences possibles de ce type de stimulation ventriculaire à long terme sont un remodelage ventriculaire, un trouble de la perfusion et de la cinétique segmentaire, une dysfonction ventriculaire systolique et/ou diastolique, une insuffisance mitrale fonctionnelle, une dilatation de l'oreillette gauche, des arythmies auriculaires et ventriculaires et l'activation du syste me nerveux sympathique. Notre étude évalue de manière rétrospective l'évolution de 150 patients stimulés dans le ventricule droit de façon permanente, implantés au CHU de Brest, afin de comparer différents sites de stimulation ventriculaire (108 à l'apex, 28 au septum inter-ventriculaire haut/infundibulum pulmonaire et 16 au septum inter-ventriculaire bas). Nos résultats montrent que chez les patients stimulés en permanence dans le ventricule droit, la localisation de la sonde ventriculaire ne semble pas avoir d'impact à long terme sur le pronostic en terme de mortalité ou de survenue d'insuffisance cardiaque. La localisation septale haute ou infundibulaire semble être associée à une incidence plus élevée de fibrillation atriale au long cours. Ce résultat sera à valider par des études prospectives randomisées multicentriques.BREST-BU Médecine-Odontologie (290192102) / SudocSudocFranceF

Value of entrainment mapping in determining the isthmus-dependent nature of atrial flutter in the presence of amiodarone.

International audienceINTRODUCTION: Entrainment mapping is a useful procedure for localizing macroreentrant tachycardia circuits. In patients with isthmus-dependent atrial flutter, entrainment mapping from the isthmus during tachycardia results in postpacing intervals (PPI) close to the tachycardia cycle length (TCL). However, the influence of antiarrhythmic drugs on the method's value is not clearly established. The aim of our study was to assess the value of entrainment mapping in the presence of amiodarone in patients undergoing radiofrequency ablation (RFA) of isthmus-dependent atrial flutter. METHODS AND RESULTS: The study consisted of 83 patients with isthmus-dependent atrial flutter: 52 were taking amiodarone at the time of RFA (group 1) and 31 were in a drug-free state (group 2). Entrainment mapping was performed from the cavotricuspid isthmus, and PPI minus TCL was determined. The two groups had similar baseline clinical characteristics. In all patients, RFA of the isthmus resulted in termination of tachycardia, confirming the isthmus-dependent nature of the flutter. TCL was significantly longer in group 1 than in group 2 (263 +/- 31 msec vs 238 +/- 27 msec, P 20 msec compared to group 2 (37% vs 10%, P = 0.01). CONCLUSION: Amiodarone significantly alters the entrainment mapping response from the isthmus. In this setting, long return cycles exceeding the TCL by >20 msec do not exclude isthmus-dependent atrial flutter

Mitral and aortic valvular disease associated with benfluorex use.

International audienceFenfluramine has been associated with an increased risk of pulmonary hypertension and valvular disease. Benfluorex is a fenfluramine derivative approved for the treatment of metabolic syndrome and type 2 diabetes mellitus. To date, only three isolated clinical cases of valvular disease and two recent case-control studies have been reported in patients exposed to benfluorex. Herein, the case is described of a patient with mitral and aortic valvular disease, with both echocardiographic and histopathological findings, who had been receiving benfluorex for several years, without any other etiology of valvular disease. The case is suggestive of toxic valvular lesions, similar to those observed previously during treatment with fenfluramine, pergolide, and cabergolide