Permanent left atrial pacing therapy may improve symptoms in heart failure patients with preserved ejection fraction and atrial dyssynchrony: a pilot study prior to a national clinical research programme

Aims Our group has recently shown that in some patients, heart failure with preserved ejection fraction (HFPEF) may be explained by ‘atrial dyssynchrony syndrome’ (ADS) due to interatrial conduction delay (IACD), a short left atrioventricular interval (LAVI), and increased left atrial (LA) stiffness. Our primary objective was to evaluate LA pacing therapy as a new treatment to restore left ventricular active filling in patients with no other known causes for HF than ADS. Methods and results Six patients with severe HFPEF with IACD (P wave duration >120 ms in lead II), short LAVI during electrophysiological studies ( 15), and no standard indication for a pacemaker were implanted with a lead …

Arrhythmia due to mild therapeutic hypothermia - a study in vitro

International audience; Introduction: In case of resuscitation after CA, the brain suffers the ischemia and the inflammation from reperfusion. To days, the only therapy available is the mild therapeutic hypothermia (MTH) : put the patient under 34°C-32°C during 12-24 hours. MTH has been shown to increase the hospital survival rate, but it has many adverse effects, among which the cardiac arrhythmia generation represents an important part (up to 34%). Cardiac culture in vitro provides a better spatial resolution than study in vivo, which could bring some insights of the mechanism of post-hypothermia arrhythmia generation. Method: Monolayer cardiac culture is prepared with cardiomyocytes from…

Impact of Midregional N‐Terminal Pro–Atrial Natriuretic Peptide and Soluble Suppression of Tumorigenicity 2 Levels on Heart Rhythm in Patients Treated With Catheter Ablation for Atrial Fibrillation: The Biorhythm Study

Background We assessed the impact of preprocedural plasma levels of MRproANP (midregional N‐terminal pro–atrial natriuretic peptide) and sST2 (soluble suppression of tumorigenicity 2) on recurrence of atrial fibrillation (AF) at 1 year after catheter ablation of AF. Methods and Results This was a prospective, multicenter, observational study including patients undergoing catheter ablation of AF. MRproANP and sST2 were measured in a peripheral venous blood preprocedure, and MRproANP was assessed in the right and left atrial blood during ablation. The primary end point was recurrent AF between 3 and 12 months postablation, defined as a documented (>30 seconds) episode of AF, flutter, or a…

Safety and efficacy of left atrial appendage occlusion with the ACP or Watchman device guided by intracardiac echocardiography from the left atrium

Abstract Background There is a paucity of randomized data regarding the safety and efficacy of the use of intracardiac echocardiography (ICE) from the left atrium (LA) to guide left atrial appendage occlusion (LAAO) procedures under local anesthesia using either of the available devices. Hypothesis The aim of this study was to compare the efficacy and safety of ICE from the LA with transesophageal echocardiography (TEE) for guidance during transcatheter LAAO procedures. Methods Single‐center, cohort study of patients undergoing LAAO with the Amplatzer Cardiac Plug or Watchman device. Procedures were guided by ICE from the LA with local anesthesia (n = 175) or TEE under general anesthesia (n…

0058 : Low circulating levels of Growth Differentiation Factor 15 (GDF-15) before coronary artery bypass surgery may predict post-operative atrial fibrillation

BackgroundPost-operative atrial fibrillation (POAF) following cardiac surgery has a high prevalence and is associated with considerable morbidity.AimsTo assess the role of GDF-15, a member of the TGFβsuperfamily, as a potential new predictor of POAF after off-pump (OFP) and on-pump (ONP) coronary artery bypass graft (CABG) surgery.MethodsThis observational study recruited the first 50 patients planned for OFP surgery and the first 50 patients planned for ONP surgery. Patients referred for CABG with the following exclusion criteria: age 80 years, previous atrial fibrillation/flutter, previous treatment with Amiodarone, previous cardiac surgery, emergency surgery. Included patients were equip…

Association between antithrombotic treatment and outcomes at 1-year follow-up in patients with atrial fibrillation: the EORP-AF General Long-Term Registry

Aims In recent years, stroke prevention in patients with atrial fibrillation (AF) has radically changed, with increasing use of non-vitamin K antagonist oral anticoagulants (NOACs). Contemporary European data on AF thromboprophylaxis are needed. Methods and results We report 1-year follow-up data from the EURObservational Research Programme in Atrial Fibrillation (EORP-AF) General Long-Term Registry. Outcomes were assessed according to antithrombotic therapy. At 1-year follow-up, 9663 (88.0%) patients had available data for analysis: 586 (6.1%) were not treated with any antithrombotic; 681 (7.0%) with antiplatelets only; 4066 (42.1%) with vitamin K antagonist (VKA) only; 3167 (32.8%) with …

Cardiovascular outcomes after cardiac resynchronization therapy in cardiac amyloidosis

Abstract Aims Cardiac resynchronization therapy (CRT) is highly effective in dilated cardiomyopathy (DCM) patients with impaired left ventricular ejection fraction (LVEF) and left bundle block branch. In cardiac amyloidosis (CA) patients, left ventricular dysfunction and conduction defects are common, but the potential of CRT to improve cardiac remodelling and survival in this particular setting remains undefined. We investigated cardiovascular outcomes in CA patients after CRT implantation in terms of CRT echocardiographic response and major cardiovascular events (MACEs). Methods and results Our retrospective study included 47 CA patients implanted with CRT devices from January 2012 to Feb…

Recurrence quantification analysis as a tool for complex fractionated atrial electrogram discrimination

International audience; Atrial fibrillation is the most encountered pathology of the heart rate. The reasons of its occurrence and its particular characteristics remain unknown, resulting from complex phenomena interaction. From these interactions emerges Complex Fractionated Atrial Electrograms (CFAE) which are useful for the ablation procedure. This study presents a method based on nonlinear data analysis, the Recurrence Quantification Analysis (RQA) applied on intracardiac atrial electrograms to detect CFAE particularities. The results obtained on areas previously tagged by a cardilogist show a good sensitivity to CFAE. Combination of RQA features offers a larger discrimination potential…

Multisite field potential recordings and analysis of the impulse propagation pattern in cardiac cells culture

To provide further insights into the impulse propagation between cardiac myocytes, we performed multiparametric studies of excitation spread with cellular resolution in confluent monolayers of cultured cardiomyocytes (CM). Simultaneous paired intracellular recordings of action potentials in two individual CM revealed slight periodic spontaneous advances/delays in the interspike time lag. Multisite field potential recordings performed with microelectrode arrays (MEA) confirmed random and iterative cycle-to-cycle changes in the direction of excitation spread. These local spontaneous variations in the cardiac impulse propagation pathways may be a safety process protecting against microscopical…

Experimental study of arrhythmia due to mild therapeutic hypothermia after resuscitation of cardiac arrest

International audience; Introduction: One of the important challenges after cardiac arrest (CA) is the neurological damage of the brain. In case of resuscitation after CA, the brain suffers the ischemia and the inflammation from reperfusion. To days, the only therapy available is the mild therapeutic hypothermia (MTH) : put the patient under 34°C-32°C during 12-24 hours. Even though that MTH has been shown to increase the hospital survival rate, it has many adverse effects, among which the cardiac arrhythmia generation represents an important part (up to 34%). Cardiac culture in vitro provides a better spatial resolution (to cellular level) than study in vivo, which could bring some insight…

Usefulness and limitations of contractile reserve evaluation in patients with low-flow, low-gradient aortic stenosis eligible for cardiac resynchronization therapy

Aims In low-flow, low-gradient aortic stenosis (LF/LG AS), the assessment of contractile reserve (CR) by dobutamine stress echocardiography (DSE) is recommended for risk stratification and treatment strategy. However, DSE may show limitations in cases of left ventricular dyssynchrony (LVD). The impact of LVD in LF/LG AS, and the feasibility of CRT in this setting have never been evaluated. We aimed to assess: (i) the proportion of LF/LG AS patients with LVD; (ii) the influence of LVD on CR at DSE; and (iii) the effects of CRT in these patients. Methods and results Thirty consecutive patients with LF/LG AS underwent DSE with study of CR. The operative risk for aortic valve replacement (AVR) …

Incomplete Timothy syndrome secondary to a mosaic mutation of the CACNA1C gene diagnosed using next-generation sequencing.

Autosomal dominant genetic diseases can occur de novo and in the form of somatic mosaicism, which can give rise to a less severe phenotype, and make diagnosis more difficult given the sensitivity limits of the methods used. We report the case of female child with a history of surgery for syndactyly of the hands and feet, who was admitted at 6 years of age to a pediatric intensive care unit following cardiac arrest. The electrocardiogram (ECG) showed a long QT interval that on occasions reached 500 ms. Despite the absence of facial dysmorphism and the presence of normal psychomotor development, a diagnosis of Timothy syndrome was made given the association of syndactyly and the ECG features.…

First-degree atrioventricular block and pseudopacemaker syndrome

Spiral wave induced numerically using electrical stimulation and comparison with experimental results.

Experiments in vitro on a Microelectrode Array (MEA) platform show that electrical stimulation can provoke the generation of spiral waves in cardiac tissue. Nevertheless, the conditions leading to this artificial fibrillation state remain unclear. In order to have a better understanding of this phenomenon, a numerical simulation study has been conducted. The results obtained with a two-dimensional FitzHugh-Nagumo model proved that it is possible to create spiral waves by adding a stimulation current under certain conditions, which are made explicit.

A hybrid stimulation strategy for suppression of spiral waves in cardiac tissue

International audience; Atrial fibrillation (AF) is the most common cardiac arrhythmia whose mechanisms are thought to be mainly due to the self perpetuation of spiral waves (SW). To date, available treatment strategies (antiarrhythmic drugs, radiofrequency ablation of the substrate, electrical cardioversion) to restore and to maintain a normal sinus rhythm have limitations and are associated with AF recurrences. The aim of this study was to assess a way of suppressing SW by applying multifocal electrical stimulations in a simulated cardiac tissue using a 2D FitzHugh-Nagumo model specially convenient for AF investigations. We identified stimulation parameters for successful termination of S…

Supraventricular tachycardias, conduction disease, and cardiomyopathy in 3 families with the same rare variant in TNNI3K (p.Glu768Lys)

IF 4.743 (2017); International audience; BackgroundRare genetic variants in TNNI3K encoding troponin-I interacting kinase have been linked to a distinct syndrome consisting primarily of supraventricular tachycardias and variably expressed conduction disturbance and dilated cardiomyopathy in 2 families.ObjectiveThe purpose of this study was to identify new genetic variants associated with inherited supraventricular tachycardias, cardiac conduction disease, and cardiomyopathy.MethodsWe conducted next generation sequencing in 3 independent multigenerational families with atrial/junctional tachycardia with or without conduction disturbance, dilated cardiomyopathy, and sudden death. We also asse…

Relationship between complex fractionated atrial electrogram patterns and different heart substrate configurations

International audience; Complex Fractionated Atrial Electrograms (CFAE) were identified as being symptomatic of reentrant activities. Signals recorded by an intracardiac catheter give an imprecise vision of the underlying phenomena that occur in the proarrhythmic substrate. In this study, phenomenological and ionic numerical models were used to simulate a small piece of the atrium substrate. The catheter measurement is also simulated numerically to take into account electrode particularities. Modifications were applied on the numerical substrate. Then stimulation scenarios were generated in the numerical substrate such as planar waves, stable or breaking spirals. Comparison between simulate…

Analysis of an Experimental Model of In Vitro Cardiac Tissue Using Phase Space Reconstruction

International audience; The in vitro cultures of cardiac cells represent valuable models to study the mechanism of the arrhythmias at the cellular level. But the dynamics of these experimental models cannot be characterized precisely, as they include a lot of parameters that depend on experimental conditions. This paper is devoted to the investigation of the dynamics of an in vitro model using a phase space reconstruction. Our model, based on the heart cells of new born rats, generates electrical field potentials acquired using a microelectrode technology, which are analyzed in normal and under external stimulation conditions. Phase space reconstructions of electrical field potential signal…

Left Atrial Remodeling and Brain Natriuretic Peptide Levels Variation after Left Atrial Appendage Occlusion

Background: Few data are available about brain natriuretic peptide (BNP) variation and left atrial remodeling after the left atrial appendage occlusion (LAAO) technique. Methods: Prospective study included all consecutive patients successfully implanted with an LAAO device. Contrast-enhanced cardiac computed tomography (CT) was performed before and 6 weeks after the procedure with reverse left atrial remodeling defined by an increase in LA volume &gt

Simultaneous cardiocerebral embolization in patients with atrial fibrillation

Cardiac arrhythmias induced by an electrical stimulation at a cellular level

To provide insights into the impulse propagation between cardiac myocytes, we performed studies of excitation spread with cellular resolution in confluent monolayers of cultured cardiomyocytes (CM). Multisite field potentials have been recorded using microelectrode arrays (MEA) technology in a basal condition and in proarrhythmic conditions induced by a high frequency electrical stimulation. The in vitro observation of spiral waves opens a new way to test the anti-arrhythmic drugs or strategies at cellular level.

A rare case report of variable degrees of atrioventricular block during atrioventricular nodal reentrant tachycardia

0057 : Preoperative Growth Differentiation Factor 15 (GDF15) as a novel biomarker of acute kidney injury after cardiac bypass surgery

ObjectivePreviously, we demonstrated that preoperative plasma GDF15 levels significantly improved the prognostic value of the EuroSCORE for mortality after cardiac surgery. Despite the strong correlation between GDF15 and renal function, no data are available regarding the potential interest of preoperative GDF15 levels to improve the prediction of acute kidney injury (AKI) after coronary artery bypass grafting (CABG).Design134 patients operated on for CABG of whom 50 underwent offpump surgery at our university hospital were included in this prospective, observational study. Exclusion criteria were age 80 years, previous atrial fibrillation/flutter, previous severe renal failure (estimated …

High prevalence of arrhythmic and myocardial complications in patients with cardiac glycogenosis due to PRKAG2 mutations

International audience; AIMS: Mutations in PRKAG2, the gene encoding for the γ2 subunit of 5'-AMP-activated protein kinase (AMPK), are responsible for an autosomal dominant glycogenosis with a cardiac presentation, associating hypertrophic cardiomyopathy (HCM), ventricular pre-excitation (VPE), and progressive heart block. The aim of this study was to perform a retrospective time-to-event study of the clinical manifestations associated with PRKAG2 mutations.METHODS AND RESULTS: A cohort of 34 patients from 9 families was recruited between 2001 and 2010. DNA were sequenced on all exons and flanking sequences of the PRKAG2 gene using Sanger sequencing. Overall, four families carried the recur…