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Left atrial-esophageal fistula (AEF) following radiofrequency ablation for atrial fibrillation is a rare and potentially lethal complication. Although surgical management is associated with improved outcomes, the optimal approach remains to be elucidated. We describe a case of AEF which was treated with a simultaneous repair of the atrium and esophagus via a right thoracotomy with an extra-pericardial off-pump approach.

Background Repair of complete atrioventricular septal defect with absent or diminutive primum defect is challenging because of atrial septal malposition and abnormal anatomy of the left atrioventricular valve. We sought to define the incidence, anatomy, and surgical outcomes of this entity. Methods We identified all patients in our institutional database presenting for complete atrioventricular septal defect repair from 2006 to 2018. Operative reports and echocardiograms were reviewed to determine the presence and size of the primum defect, atrioventricular valve anatomy, degree of atrioventricular valve regurgitation, repair method, and complications, including reoperation for atrioventricular valve regurgitation. Functionally univentricular patients and those receiving repair at an outside institution were excluded. Results Of 183 patients with complete atrioventricular septal defect, absent/diminutive primum defect occurred in 16 patients (8.7%; 10 absent, 6 diminutive). Six patients (38%) had leftward malposition of the atrium septum on the common atrioventricular valve. The rate of reoperation for left atrioventricular valve regurgitation was 31% (3 early, 2 late), for which preoperative predictors included leftward malposition of the atrial septum onto the common atrioventricular valve (4/6 patients with malposition required reoperation, P = .036, Fisher exact test). One patient exhibiting this risk factor died. The overall rate of moderate or greater left atrioventricular valve regurgitation on the most recent postoperative echocardiogram was 13% (2/16 patients; median follow-up, 141 days; range, 3-2236 days). Conclusions Complete atrioventricular septal defect with absent or diminutive primum defect is a unique variant of complete atrioventricular septal defect for which the risk of reoperation for left atrioventricular valve regurgitation after complete repair is high and risk factors include leftward malposition of the atrial septum on the common atrioventricular valve.

This series describes an innovative technique for pacing in patients with sinus node dysfunction after extracardiac Fontan surgery. This transpulmonary approach to the left atrial epi-myocardium has been successfully applied to three patients at two centers and resulted in excellent acute and midterm pacing characteristics without known complications. The principal advantage of this procedure in comparison to prior iterations is the absence of pacing material within the pulmonary venous atrium, so that future systemic thromboembolism risk is minimized. The transpulmonary approach for permanent atrial pacing offers a novel solution to the unique challenges for patients after extracardiac Fontan operation.

Background Echocardiography provides complex data on cardiac function that can be integrated into patterns of dysfunction related to the severity of cardiac disease. The aim of this study was to demonstrate the feasibility of applying machine learning (ML) to automate the integration of echocardiographic data from the whole cardiac cycle and to automatically recognize patterns in velocity profiles and deformation curves, allowing the identification of functional phenotypes. Methods Echocardiography was performed in 189 clinically managed patients with hypertension and 97 healthy individuals without hypertension. Speckle-tracking analysis of the left ventricle and atrium was performed, and deformation curves were extracted. Aortic and mitral blood pool pulsed-wave Doppler and mitral annular tissue pulsed-wave Doppler velocity profiles were obtained. These whole–cardiac cycle deformation and velocity curves were used as ML input. Unsupervised ML was used to create a representation of patients with hypertension in a virtual space in which patients are positioned on the basis of the similarity of their integrated whole–cardiac cycle echocardiography data. Regression methods were used to explore patterns of echocardiographic traces within this virtual ML-derived space, while clustering was used to define phenogroups. Results The algorithm captured different patterns in tissue and blood-pool velocity and deformation profiles and integrated the findings, yielding phenotypes related to normal cardiac function and others to advanced remodeling associated with pressure overload in hypertension. The addition of individuals without hypertension into the ML-derived space confirmed the interpretation of normal and remodeled phenotypes. Conclusions ML-based pattern recognition is feasible from echocardiographic data obtained during the whole cardiac cycle. Automated algorithms can consistently capture patterns in velocity and deformation data and, on the basis of these patterns, group patients into interpretable, clinically comprehensive phenogroups that describe structural and functional remodeling. Automated pattern recognition may potentially aid interpretation of imaging data and diagnostic accuracy.

Simulations of the ventricular flow patterns during left ventricular assist device (LVAD) support are mainly performed with idealized cylindrical inflow, neglecting the influence of the atrial vortex. In this study, the influence of the left atrium (LA) on the intra-ventricular flow was investigated via Computational Fluid Dynamics (CFD) simulations. Ventricular flow was simulated by a combined Eulerian (carrier flow)/Lagrangian (particles) approach taking into account either the LA or a cylindrical inflow section to mimic a fully support condition. The flow deviation at the mitral valve, the blood low-velocity volume as well as the residence time and shear stress history of the particles were calculated. Inclusion of the LA deflects the flow at the mitral valve by 25°, resulting in an asymmetric flow jet entering the left ventricle. This reduced the ventricular low-velocity volume by 40% (from 6.4 to 3.9 cm3), increased (40%) the shear stress experienced by particles and correspondingly increased (27%) their residence time. Under the studied conditions, the atrial geometry plays a major role in the development of intraventricular flow patterns. A reliable prediction of blood flow dynamics and consequently thrombosis risk analysis within the ventricle requires the consideration of the LA in computational simulations.

Fetal hydrothorax (FH) or pleural effusion is a clinical entity, and refers to accumulation of fetal pleural fluid, which may presents a wide spectrum of severity ranging from small, harmless effusion, to life-threatening thoracic compression (1). The perinatal mortality associated with pleural effusion is at least 50 %. Cardiac and extra-cardiac abnormalities may accompany the hydrothorax and their presence also affects the prognosis (2). Division of the right atrium, first reported in 1868, also known as cor triatriatum dexter, is extremely a rare congenitally abnormality, in which persistence of right valve of the embryonic systemic venous sinus divides the right atrium into two chambers. The embryonic valvar structures, whose significance during fetal life is to direct the richly oxygenated inferior caval venous blood across to the left atrium and thence to the aorta, normal regress in late fetal life and early childhood. Cytomegalovirus (CMV) is a common human virus, member of herpes virus family, and the most common cause of intrauterine infection, occurring in 0.2 % to 2.2 % of life births (3,4). This report describes antenataly diagnosed a case of a divided right atrium, associated with severe form of hydrothorax and Cytomegalovirus infection. Here we present a fetus with sever hydrothorax associated with divided right atrium and cytomegalovirus infection.

The fish heart is a unique model to compare the resistance to hypoxia of its two chambers (atrium and ventricle), which are different in the structure and functional loads. The activity of oxydoreductases malate dehydrogenase (MDH, 1.1.1.37) and lactate dehydrogenase (LDH, 1.1.1.27), as well as the parameters of the adenylate system in the heart chambers of a Black Sea scorpaena, were studied under acute hypoxia (0.9–1.2 mg O2·L–1, 90 min). Despite the leading functional role of the ventricle, MDH activity in this heart compartment tended to decrease compared to the atrium in the absence of differences in LDH activity. At the same time, the difference in the level of adenylates (ATP, ADP, AMP), total adenylate pool (AP), and adenylate energy charge (AEС) between the atrium and ventricle was statistically nonsignificant, although the absolute value of the ventricular AP was almost twice as large as the atrial AP. The AEC values of the atrium and ventricle perfused only with venous blood did not exceed ~0.7 (vs. the maximum of this parameter ~0.9–1.0), apparently reflecting the energy status of tissues initially adapted to hypoxia. Under acute hypoxia, there were found two strategies for energy metabolism transformation in the heart chambers in the form of a 2.4-fold drop in MDH activity (р < 0.05) in the atrium and a 2.2-fold increment in LDH activity (р < 0.05) in the ventricle. Probably, the decline in MDH activity in the atrial tissue was determined by a more passive function of this heart chamber in providing the blood flow. The exposure to acute hypoxia led to a decrease in the level of adenylate nucleotides and an AEC decline in the heart chambers, as pronounced most distinctly in the ventricular myocardium. When decreasing PO2, the AEC in the heart chambers shifted within quite a narrow range (from 0.7 to 0.6), indicating the retention of a certain stationary energy status achieved by inhibition of ATP consumption or demand. The putative mechanism for retaining the AEC may be based on the negative chronotropic effect of hypoxia.

The article describes a method for hearts of lower vertebrates in the early stages of their development. To achieve sufficient spatial resolution, the method uses an acoustic microscope with mechanical scanning of a focusing ultrasound transducer, the received signal of which is recorded as a function of spatial coordinates and time. The heart of weatherfish Misgurnus fissilis at the prelarval stage of development was examined with a pulsed acoustic microscope. The center frequency and duration of the envelope of the recorded reflected pulses were 70 MHz and 30 ns, respectively. Processing of the recorded spatiotemporal signal made it possible to visualize movement of tissues of the ventricle, atrium, and valves in the ventricular region of the heart, determine the period of heartbeats, and identify heart rhythm phases. It is shown that the characteristic sizes of the ventricle and atrium are 150–300 µm. The responses of moving blood elements were identified and the speed of their movement in different areas of the heart were measured as a function of time. It was found that the blood flow rate reaches a maximum of 2.5 mm/s in the diastolic period in the ventricular region of the heart. In other regions, peaks in the diastolic and systolic periods range from 1.5 to 0.8 mm/s. In accordance with the principle of high-power Doppler sonography, the change in density of moving blood elements was visualized as a function of time.

We report the case of a 41-year-old female patient with symptoms of cerebrovascular accident manifesting with loss of consciousness during episodes of cough. Computed multislice chest tomography showed a 7.3- by 4.15-cm mass in the left atrium. A transesophageal echocardiogram showed a giant mass in the left atrium that passed through the mitral valve to the left ventricle, and severe obstructive stenosis was suggested by the mean transmitral gradient. After a comprehensive assessment of the mass, we decided to perform surgery. The pedunculated and fragile mass was attached to the interatrial septum with its handle, and the majority of it prolapsed through the mitral valve to the left ventricle and became stacked among the mitral valve leaflets. The removed mass was analyzed histopathologically and was found to be a myxoma. It is important for the cardiac surgeon to surgically remove an atrial myxoma because of the risks associated with embolization, including sudden death, as myxoma can block the blood supply from the atrium to the ventricle.

Introduction: Ebstein’s anomaly is a rare abnormality of the heart associated with atrialization right ventricle and apical (downward) displacement of the tricuspid valve functional annulus. Twenty percents of patients with Ebstein’s anomaly accompanied with accessory pathway. The dilatation of atrium and aging process may develop atrial fibrillation (AF).Case Description: A 35 years old patient with recurrency palpitation, accompanied with dizziness and epigastric discomfort. He had history of taking propafenone 3 x 150 mg for long time while the palpitation recurrent. He was hospitalization due to propafenone could not suppress the palpitation. During monitor in hospital revealed haemodynamic stable with heart rate 160-180 beats/minute irregularly irregular. The electrocardiography showed atrial fibrillation with pre-excitation WPW syndrome. We performed electrical cardioversion 100 joule. Then the atrial fibrillation was convert to sinus rhythm with WPW pattern. The propafenone 3 x 150mg was continued. The patient was performed catheter radiofrequency ablation of the accessory pathway. Electrophysiology showed AV fusion at right anteroseptal pathway and preexcited atrial fibrillation with shortest RR interval 220 ms that converted by cardioversion. The ablation was successfully performed. Discussion: The accessory pathway is a complication of ebstein anomaly. Digoxin, beta-blockers, diltiazem, verapamil, and amiodarone are potentially harmful in pre-excited atrial fibrillation. Propafenone reduces fast inward potential by sodium channels, reduces spontaneous automaticity and prolongs the effective refractory periode so could be used in this case. Catheter ablation of accessory pathway in Ebstein anomaly with WPW syndrome was class I recommendation. In our case, the accessory pathway was successfully ablated.

Background Activated factor X (FXa), which contributes to chronic inflammation via protease-activated receptor 2 (PAR2), might play an important role in atrial fibrillation (AF) arrhythmogenesis. This study aimed to assess whether PAR2 signaling contributes to AF arrhythmogenesis and whether rivaroxaban ameliorates atrial inflammation and prevents AF.Methods and Results:In Study 1, PAR2 deficient (PAR2-/-) and wild-type mice were infused with angiotensin II (Ang II) or a vehicle via an osmotic minipump for 2 weeks. In Study 2, spontaneously hypertensive rats (SHRs) were treated with rivaroxaban, warfarin, or vehicle for 2 weeks after 8 h of right atrial rapid pacing. The AF inducibility and atrial remodeling in both studies were examined. Ang II-treated PAR2-/- mice had a lower incidence of AF and less mRNA expression of collagen1 and collagen3 in the atrium compared to wild-type mice treated with Ang II. Rivaroxaban significantly reduced AF inducibility compared with warfarin or vehicle. In SHRs treated with a vehicle, rapid atrial pacing promoted gene expression of inflammatory and fibrosis-related biomarkers in the atrium. Rivaroxaban, but not warfarin, significantly reduced expression levels of these genes. Conclusions The FXa-PAR2 signaling pathway might contribute to AF arrhythmogenesis associated with atrial inflammation. A direct FXa inhibitor, rivaroxaban, could prevent atrial inflammation and reduce AF inducibility, probably by inhibiting the pro-inflammatory activation.

A high-performance smoke exhaust system is vital for maintaining a tenable environment during fire accidents evacuation. This study proposes a novel vortex flow driven smoke exhaust system to delay the smoke filling process during the atrium fire accident. The complex fluid movement and combustion reactions were predicted using Fire Dynamics Simulator, and the predicted smoke filling process was identified by the least-square method. Good agreements between numerical predictions and experimental measurements for vertical temperature, tangential velocity profile and smoke interface height were achieved. The numerical outcomes revealed that the amount of fresh air supplied, heat release rate and exhaust fan's rate determined the smoke interface's final height. A parametric study was also carried out to investigate the dominating factor in maintaining a stable vortex flow to maximize the smoke exhaust efficiency. Numerical results showed that the vortex flow smoke exhaust system could slow down the smoke filling, and the stability of the swirling fire is crucial for the system's performance.

Background Total anomalous pulmonary venous return (TAPVR) refers to an anomaly in which all of the pulmonary veins drain directly or indirectly to the systemic venous circulation. However, unusual types constitute approximately 5% or less of TAPVRs and there may be obstruction or discontinuity of pulmonary vein at various levels. Case presentation A 3-month-old infant was presented to us with history of poor feeding, respiratory distress and desaturations. The routine echocardiographic investigation initially confirmed the diagnosis of an atrial septal defect with dextrocardia. However, due to disproportionate severity of symptoms and congestive heart failure a cardiac computer tomography angiogram was done that revealed a rare finding of connection of pulmonary veins fused with the posterior atrium, but on the rightward side of the deviated atrial septum. Therefore, pulmonary veins entered a sinus that drains directly into the right atrial superior-posterior wall. During surgical repair, we found an area of absent pericardium in the diaphragmatic surface of the heart. The patient underwent total repair of the TAPVR and patch reconstruction of the pericardial defect. The patient is doing well at 6-month follow up. Conclusions The septum primum malposition defect resulting in TAPVR is a very rare congenital anomaly that can be rarely seen without any heterotaxy. The anomalous features including absent pericardium and dextrocardia were present in this patient have not been described previously with TAPVR. Therefore, we have hypothesized the embryological correlation of absent pericardium and cardiac malposition in such case. Transthoracic echocardiography with Doppler interrogation is a reliable method for diagnosing this condition. In case of suboptimal echocardiographic image due to cardiac position, unclear anatomy or unexplained symptoms, advanced imaging such as computer tomographic angiography or cardiac magnetic resonance imaging can be very helpful. Preoperative proper diagnosis of this anomaly facilitates successful surgical management with excellent outcome.

The complex post-surgical anatomy after the Senning procedure presents several challenges for catheter ablation. Transbaffle approach allows access to the pulmonary venous atrium and better catheter manipulation. However, this modified transseptal puncture can be challenging to perform. The authors present the case of a 29-year-old woman who underwent a Senning procedure for dextro-transposition of the great arteries. The patient had recurrent episodes of atrial flutter despite adequate antiarrhythmic therapy and was referred for catheter ablation. […] Transbaffle Puncture Using Multimodality [...]

AIM: Tunneled hemodialysis (HD) catheters can be used instantly, but there are several anatomical variables that could impact it survival. This study aimed to examine the impact of different novel anatomic variables, with catheter replacement. METHODS: In a single-center a prospective cohort in chronic kidney disease G5 patients were conducted. The primary outcome was to determine the factors associated with catheter replacement during the first six month of follow-up. All procedures were performed without fluoroscopy. Three anatomic regions for catheter tip position were established: considered as superior vena cava (SVC), cavo-atrial junction (CAJ) and mid-to deep atrium (MDA). Many other anatomical variables were measured. Catheter-related bloodstream infection was also included. RESULTS: Between January 2019 and January 2020 a total of 75 patients with tunneled catheter insertion were analyzed. Catheter replacement at 6-month occur in 10 (13.3%) patients. By multivariate analysis, the incorrect catheter tip position (SVC) (OR 1.23, 95% CI 1.07 to 1.42, p

Background In complex congenital heart disease, supraventricular arrhythmia develops long term after surgical repair. The arrhythmia could have pharmacological tolerance and sometimes be fatal. We report our experiences with puncturing tough or calcified surgical repair material to access the pulmonary venous atrium for the purpose of the management of arrhythmia in complex congenital heart disease with surgical correction. Methods From June 2016, subsequent 9 patients underwent the procedure. Their age at the procedure ranged from 11 to 43 years old (median 26.4 years old). Surgical procedures were Mustard procedure (XenomedicaⓇ) in 6, lateral tunnel total cavo-pulmonary connection with autologous pericardium in 2, and extra-cardiac total cavo-pulmonary connection with expanded polytetrafluoroethylene (ePTFE) tube in 1. Results Multi-planar reconstruction imaging by cardiac computed tomography was done for making plans before the procedures. Under intracardiac echocardiography guidance, an 8 French steerable sheath was perpendicularly adjusted to target objects. The sharpened edge of 0.014 inch guide wire penetrated with gentle forward force. Subsequently, the puncture site was dilated from a small balloon to a large one step by step. In all patients, penetration was successfully completed. Catheter ablation was achieved in 8 patients and a pacemaker was implanted through the re-canalized superior caval vein in 1 patient. No complications were recorded. Conclusion The trans-catheter puncture of the synthetic or calcified material is safe and feasible, although careful planning is required with imaging. A steerable sheath could easily be controlled to the make appropriate angle to the target object for preventing slippage and conveying effective force.

Background: In areas of pulmonary embolism (PE), the enhancement of pulmonary veins on computed tomography pulmonary angiography (CTPA) should be decreased due to reduced arterial perfusion. Purpose: The purpose of this study was to investigate the accuracy of contrast density measurements (differences) in all pulmonary veins and the left atrium for the prediction of PE. Materials and Methods: 75 patients with PE and 22 patients without PE on CTPA were included. 4 readers measured the enhancement of the blood in the pulmonary vein immediately before the entrance to the left atrium, right after the aperture, in the center of the left atrium, in the pulmonary trunk and in the aorta. Enhancement of the pulmonary veins with and without upstream PE, and ROC curves with HU thresholds for optimal sensitivity and specificity for PE were calculated. Results: More PEs were found in the right and lower lobes. PE-affected lobes demonstrated 13.8+/-45 HU less enhancement in the pulmonary vein, compared to a paired non-affected pulmonary vein of the same patient (P < 0.0001). On average, non-affected pulmonary veins demonstrated no difference in enhancement compared to each other: 0.2 +/-21 HU. The optimal cutoff level in the ROC curve analysis for PE affection proved to be decreasing enhancement in the pulmonary vein of more than 10 HU, compared to the atrium. Conclusion: Decreasing enhancement in the pulmonary vein of more than 10 HU compared to the atrium could provide additional information and confidence in the diagnosis of PE.

Recently, the estimated total atrial conduction time measured using tissue Doppler imaging (PA-TDI duration) has been reported as a more accurate predictor of atrial fibrillation (AF) recurrence after catheter ablation than left atrial volume index (LAVI). The PA-TDI duration is considered to reflect electrical and structural remodeling in the right atrium (RA) and left atrium (LA). We sought to investigate the association between AF recurrence and PA-TDI duration after AF ablation. We studied 209 patients who underwent radiofrequency ablation for paroxysmal AF and 75 patients who underwent second ablation for AF recurrence. We assessed the duration from the onset of the P wave on the surface electrocardiogram to the atrial electrogram in distal coronary sinus (CS) (PA-CSd duration) indicating electrical remodeling of the atrium, the PA-CS proximal duration (PA-CSp duration) representing electrical remodeling of RA, and the conduction time in CS (proximal to distal) (CSp-CSd duration) reflecting electrical remodeling of LA. We also measured LAVI as a marker of structural remodeling of LA. The PA-TDI duration had a positive correlation with PA-CSd duration. In the patients with AF recurrence, PA-TDI duration, PA-CSd duration, and CSp-CSd duration in the second ablation were significantly longer than those in the first (p

The autonomic nervous system (ANS) is known to play an important role in the genesis and maintenance of atrial fibrillation (AF). Biomolecular and genetic mechanisms, anatomical knowledges with recent diagnostic techniques acquisitions, both invasive and non‐invasive, have enabled greater therapeutic goals in patients affected by AF related to ANS imbalance. Catheter ablation of ganglionated plexi (GP) in the left and right atrium has been proposed in varied clinical conditions. Moreover interesting results arise from renal sympathetic denervation and vagal nerve stimulation. Despite all this, in the scenario of ANS modulation translational strategies we necessary must consider the treatment or correction of dynamic factors such as obesity, obstructive sleep apnea, lifestyle, food, and stress. Finally, new antiarrhythmic drugs, gene therapy and “ablatogenomic” could be represent exciting future therapeutic perspectives., Cardioneuroablation and cardioneuromodulation for patients affected by AF related to ANS imbalance.

While the advancement of perioperative management has expanded Fontan candidacy, not all patients have a successful postoperative course. Our case was a right isomerism patient who could not leave the ICU due to high central venous pressure and low output syndrome. Initial observation of the monitor ECG showed his rhythm to be supraventricular, however, an echocardiogram indicated simultaneous contraction of the atrium and ventricle, implying a junctional rhythm. While neither central venous pressure nor blood pressure improved with temporary pacing, better central venous and pulmonary venous blood flow patterns during pacing unraveled its positive impact. The patient successfully left the ICU after permanent pacing implantation. Hemodynamic study revealed a beneficial impact of atrial pacing in securing cardiac output and ventricular preload, lowering central venous pressure, and shortening blood transit time, which is partly attributed to the optimization of the fenestration function in reservation of the preload. Our case emphasizes the significant advantage of atrial pacing in a failing Fontan patient with junctional rhythm by reducing venous congestion and maximizing the benefit of fenestration.

This paper aims to investigate detailed mechanical interactions between the pulmonary haemodynamics and left heart function in pathophysiological situations (e.g. atrial fibrillation and acute mitral regurgitation). This is achieved by developing a complex computational framework for a coupled pulmonary circulation, left atrium and mitral valve model. The left atrium and mitral valve are modelled with physiologically realistic three-dimensional geometries, fibre-reinforced hyperelastic materials and fluid–structure interaction, and the pulmonary vessels are modelled as one-dimensional network ended with structured trees, with specified vessel geometries and wall material properties. This new coupled model reveals some interesting results which could be of diagnostic values. For example, the wave propagation through the pulmonary vasculature can lead to different arrival times for the second systolic flow wave (S2 wave) among the pulmonary veins, forming vortex rings inside the left atrium. In the case of acute mitral regurgitation, the left atrium experiences an increased energy dissipation and pressure elevation. The pulmonary veins can experience increased wave intensities, reversal flow during systole and increased early-diastolic flow wave (D wave), which in turn causes an additional flow wave across the mitral valve (L wave), as well as a reversal flow at the left atrial appendage orifice. In the case of atrial fibrillation, we show that the loss of active contraction is associated with a slower flow inside the left atrial appendage and disappearances of the late-diastole atrial reversal wave (AR wave) and the first systolic wave (S1 wave) in pulmonary veins. The haemodynamic changes along the pulmonary vessel trees on different scales from microscopic vessels to the main pulmonary artery can all be captured in this model. The work promises a potential in quantifying disease progression and medical treatments of various pulmonary diseases such as the pulmonary hypertension due to a left heart dysfunction.

AimsPatients with arrhythmogenic right ventricular cardiomyopathy (ARVC) have increased prevalence of atrial arrhythmias indicating atrial involvement in the disease. We aimed to assess the long-term evolution of P-wave indices as electrocardiographic (ECG) markers of atrial substrate during ARVC progression.Methods and resultsWe included 100 patients with a definite ARVC diagnosis according to 2010 Task Force criteria [34% females, median age 41 (inter-quartile range 30–55) years]. All available sinus rhythm ECGs (n = 1504) were extracted from the regional electronic ECG databases and automatically processed using Glasgow algorithm. P-wave duration, P-wave area, P-wave frontal axis, and prevalence of abnormal P terminal force in lead V1 (aPTF-V1) were assessed and compared at ARVC diagnosis, 10 years before and up to 15 years after diagnosis.Prior to ARVC diagnosis, none of the P-wave indices differed significantly from the data at ARVC diagnosis. After ascertainment of ARVC diagnosis, P-wave area in lead V1 decreased from −1 to −30 µV ms at 5 years (P = 0.002). P-wave area in lead V2 decreased from 82 µV ms at ARVC diagnosis to 42 µV ms 10 years after ARVC diagnosis (P = 0.006). The prevalence of aPTF-V1 increased from 5% at ARVC diagnosis to 18% by the 15th year of follow-up (P = 0.004). P-wave duration and frontal axis did not change during disease progression.ConclusionInitial ARVC progression was associated with P-wave flattening in right precordial leads and in later disease stages an increased prevalence of aPTF-V1 was seen.

Objectives After surgery, inflammation is a prominent factor influencing postoperative atrial fibrillation. Myeloperoxidase is a major contributor to inflammatory responses after surgical tissue damage. We evaluated whether myeloperoxidase is associated with postoperative atrial fibrillation clinically and in an animal model. Methods This prospective cohort study included patients undergoing isolated coronary artery bypass grafting. Myeloperoxidase concentrations in blood and pericardial fluid were determined at baseline and 6, 12, and 18 hours after coronary artery bypass grafting. Myeloperoxidase activity in blood, pericardial fluid, and atrium were also evaluated in a canine coronary artery bypass grafting model. Electrophysiologic, histologic, and immunohistochemistry analyses were performed to explore underlying mechanisms. Results Postoperative atrial fibrillation occurred in 45 of 137 patients (32.8%). Patients with postoperative atrial fibrillation had significantly higher serum and pericardial myeloperoxidase levels. Individual clinical and surgical factors had moderate predictive value (area under the curve, 0.760) for postoperative atrial fibrillation. Discrimination improved remarkably when myeloperoxidase was combined with other parameters (area under the curve, 0.901). Pericardial myeloperoxidase at 6 hours postoperatively was the strongest independent predictor of postoperative atrial fibrillation (odds ratio, 19.215). The rate of postoperative atrial fibrillation increased exponentially across pericardial myeloperoxidase grades. Compared with controls, coronary artery bypass grafting–treated dogs showed higher atrial fibrillation vulnerability and maintenance, shorter atrial effective refractory period, attenuated connexin 43 expression, and increased myocardial and pericardial myeloperoxidase activity. Connexin 43 expression and atrial effective refractory period were strongly negatively correlated with myocardial and pericardial myeloperoxidase activity. Conclusions Myeloperoxidase is linked to postoperative atrial fibrillation, and the ability to predict postoperative atrial fibrillation was remarkably improved by adding pericardial myeloperoxidase. Myeloperoxidase-related atrial structural and electrical remodeling is a physiologic substrate for this arrhythmia.

Background Although epicardial structures around the atrium such as adipose tissue possess arrhythmogenicity, little is known about atrial tachycardias (ATs) originating from epicardial sites (Epi‐ATs). This study aimed to elucidate the prevalence, characteristics, and outcome after radiofrequency catheter ablation (RFCA) of Epi‐ATs and to reveal the association between Epi‐ATs and the epicardial structures. Methods The electrocardiographic, electrophysiologic, and anatomical properties and results of RFCA were analyzed in 42 patients with a total of 49 ectopic ATs. Results Six Epi‐ATs (12%) were observed in six patients (14%). Four of six were respiratory cycle‐dependent ATs and one was a swallowing‐induced AT. The Epi‐AT origins were adjacent to a pulmonary vein (five cases) and vein of Marshall (one case). A Valsalva maneuver or atropine infusion to define the arrhythmia mechanism affected the appearance of the Epi‐ATs. The congruity rate between epicardial adipose tissue and the AT origin was significantly higher (100% vs. 44%, p = .045), and the epicardial adipose tissue volume of the atrium was significantly larger (104.1 vs. 64.6 ml, p = .04) in the Epi‐AT group. Endocardial RFCA targeting the AT foci resulted in acute success in five of five cases. However, electrical isolation including of the AT foci resulted in acute failures (two of three cases) or a recurrence (one of one case). Conclusions Six Epi‐ATs were associated with thoracic veins and epicardial arrhythmogenic structures. The main cause provoking the Epi‐ATs was associated with autonomic nerve activity.

We herein report a 60-year-old woman with long-standing persistent atrial fibrillation (AF) who developed QT prolongation and torsade de pointes (TdP) after pulmonary vein isolation (PVI). When electrical cardioversion was performed three months before PVI, prominent QT prolongation was not observed. QT prolongation emerged after PVI and was sustained until AF recurrence on the third day after ablation, and TdP disappeared along with AF recurrence. PVI affects the ganglionated plexi around the atrium, leading to modification of the intrinsic cardiac autonomic system. This case indicates that PVI has the potential risk of inducing lethal ventricular arrhythmias due to QT prolongation.

The maximum left atrial volume index is the most widely used metric for assessing the left atrium in hypertrophic cardiomyopathy; however, it may be normal in the early phases of the disease.To assess whether pediatric hypertrophic cardiomyopathy patients with normal maximum left atrial volume index have impaired atrial functions on cardiac magnetic resonance imaging (MRI).A total of 26 pediatric hypertrophic cardiomyopathy patients and 24 age-matched children, as controls, were enrolled in the study. The left atrial reservoir, conduit and booster strain were calculated from two orthogonal planes and the left atrial volumes were calculated using the biplanar method. The extent of left ventricular late gadolinium enhancement (LGE-%) was calculated using the thresholding method. The left ventricular early diastolic longitudinal strain rate was calculated to assess diastolic dysfunction.The maximum left atrial volume index of the children with hypertrophic cardiomyopathy and the controls were not significantly different (P0.05). Most of the left atrial functional indices were worse in children with hypertrophic cardiomyopathy (P0.05), yet no difference was observed between the left atrial booster strains of the two groups (P0.05). The left atrial conduit strain showed moderate to good negative correlations with left ventricular LGE-% and diastolic dysfunction.Left atrial conduit and reservoir strains are impaired in pediatric hypertrophic cardiomyopathy patients with normal maximum left atrial volumetric indices. Most left atrial strain parameters are closely linked to left ventricular LGE-% and diastolic dysfunction. Left atrial strain analysis may reveal subtle functional changes in the atrium before the increase in the maximum volume index.

Aims Genetically altered mice are powerful models to investigate mechanisms of atrial arrhythmias, but normal ranges for murine atrial electrophysiology have not been robustly characterized. Methods and results We analyzed results from 221 electrophysiological (EP) studies in isolated, Langendorff-perfused hearts of wildtype mice (114 female, 107 male) from 2.5 to 17.7 months (mean 7 months) with different genetic backgrounds (C57BL/6, FVB/N, MF1, 129/Sv, Swiss agouti). Left atrial monophasic action potential duration (LA-APD), interatrial activation time (IA-AT), and atrial effective refractory period (ERP) were summarized at different pacing cycle lengths (PCLs). Factors influencing atrial electrophysiology including genetic background, sex, and age were determined. LA-APD70 was 18 ± 0.5 ms, atrial ERP was 27 ± 0.8 ms, and IA-AT was 17 ± 0.5 ms at 100 ms PCL. LA-APD was longer with longer PCL (+17% from 80 to 120 ms PCL for APD70), while IA-AT decreased (−7% from 80 to 120 ms PCL). Female sex was associated with longer ERP (+14% vs. males). Genetic background influenced atrial electrophysiology: LA-APD70 (−20% vs. average) and atrial ERP (−25% vs. average) were shorter in Swiss agouti background compared to others. LA-APD70 (+25% vs. average) and IA-AT (+44% vs. average) were longer in 129/Sv mice. Atrial ERP was longer in FVB/N (+34% vs. average) and in younger experimental groups below 6 months of age. Conclusion This work defines normal ranges for murine atrial EP parameters. Genetic background has a profound effect on these parameters, at least of the magnitude as those of sex and age. These results can inform the experimental design and interpretation of murine atrial electrophysiology.

The fish heart is a unique model to compare the resistance to hypoxia of its two chambers (atrium and ventricle), which are different in the structure and functional loading. The activity of oxydoreductases malate dehydrogenase (MDH, 1.1.1.37) and lactate dehydrogenase (LDH, 1.1.1.27), as well as the parameters of the adenylate system in the heart chambers of a Black Sea scorpaena, were studied under acute hypoxia (0.9–1.2 mg O2·L–1, 90 min). Despite the leading functional role of the ventricle, MDH activity in this heart compartment tended to decrease compared to the atrium in the absence of differences in LDH activity. At the same time, the difference in the level of adenylates (ATP, ADP, AMP), total adenylate pool (AP), and adenylate energy charge (AEС) between the atrium and ventricle was statistically nonsignificant, although the absolute value of the ventricular AP was almost twice as large as the atrial AP. The AEC values of the atrium and ventricle perfused only with venous blood did not exceed ~0.7 (vs. the maximum of this parameter ~0.9–1.0), apparently reflecting the energy status of tissues initially adapted to hypoxia. Under acute hypoxia, there were found two strategies for energy metabolism transformation in the heart chambers in the form of a 2.4-fold drop in MDH activity (р < 0.05) in the atrium and a 2.2-fold increment in LDH activity (р < 0.05) in the ventricle. Probably, the decline in MDH activity in the atrial tissue was determined by a more passive function of this heart chamber in providing the blood flow. The exposure to acute hypoxia led to a decrease in the level of adenylate nucleotides and an AEC decline in the heart chambers, as pronounced most distinctly in the ventricular myocardium. When decreasing PO2, the AEC in the heart chambers shifted within quite a narrow range (from 0.7 to 0.6), indicating the retention of a certain stationary energy status achieved by inhibition of ATP consumption or demand. The putative mechanism for retaining the AEC may be based on the negative chronotropic effect of hypoxia.

Aims Unipolar voltage (UV) mapping is increasingly used for guiding ablative therapy of atrial fibrillation (AF) as unipolar electrograms (U-EGMs) are independent of electrode orientation and atrial wavefront direction. This study was aimed at constructing individual, high-resolution sinus rhythm (SR) UV fingerprints to identify low-voltage areas and study the effect of AF episodes in patients with mitral valve disease (MVD). Methods and results Intra-operative epicardial mapping (interelectrode distance 2 mm) of the right and left atrium, Bachmann’s bundle (BB), and pulmonary vein area was performed in 67 patients (27 male, 67 ± 11 years) with or without a history of paroxysmal AF (PAF). In all patients, there were considerable regional variations in voltages. UVs at BB were lower in patients with PAF compared with those without [no AF: 4.94 (3.56–5.98) mV, PAF: 3.30 (2.25–4.57) mV, P = 0.006]. A larger number of low-voltage potentials were recorded at BB in the PAF group [no AF: 2.13 (0.52–7.68) %, PAF: 12.86 (3.18–23.59) %, P = 0.001]. In addition, areas with low-voltage potentials were present in all patients, yet we did not find any predilection sites for low-voltage potentials to occur. Conclusion Even in SR, advanced atrial remodelling in MVD patients shows marked inter-individual and regional variation. Low UVs are even present during SR in patients without a history of AF indicating that low UVs should carefully be used as target sites for ablative therapy.

OBJECTIVES Tissue reaction to transcatheter mitral valve replacement in the mitral annulus remains to be elucidated. METHODS Trileaflet porcine pericardial valves were sewn onto self-expanding d-shaped nitinol stents, which were delivered transapically and in an off-pump fashion into the mitral position of 10 pigs. After at least 4 weeks of follow-up, gross pathological assessment and histological examination were performed. The specimens were stained with Movat’s pentachrome, Elastica-van-Gieson and von Kossa staining. The leucocytes, B cells, T cells or macrophages were detected by specific immunohistochemical staining. RESULTS Proper stent positioning in the mitral annulus was achieved in 9/10 animals. Nine of 10 animals survived the desired observation period. In all but one, the mitral valve stent was well integrated into the left atrium and perpendicularly embedded into the annulus by 85 ± 24%. One animal had minor fractures in the nitinol struts and another animal showed tearing of 1 of 4 tethers. Histological examination demonstrated no major tissue reaction with the nitninol struts but well-preserved overall structures around the mitral annulus in 8/9 cases. CONCLUSIONS This is the first report demonstrating good in-growth of transcatheter-delivered anatomically shaped mitral valve stents after at least 4 weeks of follow-up. Histological examination demonstrated progressive healing and neointimalization.

Background ‘Idiopathic’ lead macrodislodgement may be due to Twiddler’s syndrome depending on active twisting of pulse generator within subcutaneous pocket. All leads are involved, at any time from implantation, and frequently damaged. In the past few years, a reel syndrome was also observed: retraction of pacemaker leads into pocket without patient manipulation, owing to lead circling the generator. In other cases, a ‘ratchet’ mechanism has been postulated. Reel and ratchet mechanisms require loose anchoring, occur generally briefly after implantation, with non-damaged leads. We report the first case of an active-fixation coronary sinus lead selective macrodislodgement involving such ratchet mechanism. Case summary A 65-year-old man underwent biventricular defibrillator device implantation, with active-fixation coronary sinus lead. Eight months later, he complained of muscle contractions over device pocket. At fluoroscopy, coronary sinus lead was found near to pocket, outside of thoracic inlet. Atrial and ventricular leads were in normal position. After opening pocket, a short tract of coronary sinus lead appeared anteriorly dislocated to generator, while greater length of lead body twisted a reel behind. The distal part of lead was found outside venous entry at careful dissection. Atrial and ventricular leads were firmly anchored. Discussion Our case is a selective ‘Idiopathic’ lead macrodislodgement, possibly due to a ratchet mechanism between the lead and the suture sleeve, induced by normal arm motion; such mechanism incredibly, and for first time in literature involves a coronary sinus active-fixation lead. Conclusion Careful attention should always be paid to secure anchoring even of active-fixation coronary sinus leads.

In a 6-month-old, intact female, Japanese spitz presenting with severe dyspnea, lung ultrasonography revealed confluent B lines associated with severe echocardiographic left sided volume overload and systolic dysfunction. A congenital shunt or valvular dysplasia was not demonstrable. On electrocardiogram, there was a constant sinus rhythm, respectively sinus tachycardia. Cardiac troponin I was normal. Within 2 days of admission, the dog died of heart failure. On macroscopic postmortem examination, the left ventricle and atrium were markedly dilated, and the left ventricular endocardium had a mild diffuse whitish appearance. Histopathology revealed moderate to severe thickening of the left ventricular endocardium, composed mostly of abundant elastic fibers and fewer collagen fibers, diagnostic for endocardial fibroelastosis. In addition, there were mild degenerative changes of the atrioventricular valves. Endocardial fibroelastosis is a rare congenital disease and should be considered in a young dog if more common causes of echocardiographic dilated cardiomyopathy phenotype are ruled out.

We describe angiographic findings of sinus node arteries (SNAs), focusing in the large sinus node artery (LSNA) variants, regarding the blood supply of the SN and atrial myocardium. We examined the SN arteries via postmortem angiographic visualization in six hundred hearts derived from victims of various accidents. The main stem or a branch of the SNA supplied the right atrium (RA) and part of the interatrial septum (IS) in 32% of cases (Group A), one atrium, the IS and a small part of the other atrium (Group B) in 39% and the entire atrial myocardium (LSNAs) (Group C) in 29%. Forty-two percent (42%) of LSNAs were arising from the anterior part of the right coronary artery (RCA) (type 1), 9% from its intermediate part (type 2) and 49% from the posterolateral portion of the left circumflex artery (LCx) (type 3). Type 2 can be injured by surgical procedures, type 3 by interventional ones, while type 1 is not affected by any. The SN area was supplied in Groups A and B by the main stem of SN arteries in 370 cases (62%) and by branches (Br) in 55 (9%). The 175 cases of group C (29%) were supplied only by branches. The clockwise (40% of cases) and counterclockwise rotations (60%) of the SNA around the superior vena cava, concern surgical procedures. The above findings are essential for every day surgical and interventional procedures.

Background A systemic right ventricle (RV) after atrial switch in transposition of the great arteries (TGA) or congenitally corrected TGA (ccTGA) often results in advanced heart failure in adulthood. Case summary Four patients with INTERMACS Class III underwent durable ventricular assist device (VAD) implantation for a systemic RV. Two patients were diagnosed with ccTGA and underwent tricuspid valve replacement, and two were diagnosed with TGA in childhood and underwent Mustard repair. The two patients with ccTGA received an EVAHEART (Sun Medical, Nagano, Japan) and HeartMate 3 (Abbott Laboratories, Abbott Park, IL, USA) at the age of 56 years and 34 years, respectively. Of the patients with TGA, one received a Heartmate II at age 40 years, and one received a HeartMate 3 at age 40 years. All patients were weaned from cardiopulmonary bypass without subpulmonic VAD support and transferred to the intensive care unit with optimum VAD support. No in-hospital deaths, cerebrovascular accidents, or other major complications occurred. The post-VAD right heart catheter study showed a remarkable reduction in pulmonary capillary wedge pressure in all patients. Discussion The indications for and surgical technique of durable VAD implantation for a systemic RV after atrial switch of TGA or ccTGA have not been fully established. A durable VAD, including the HeartMate 3, was successfully implanted in four such patients in this study. Pre-operative three-dimensional computed tomography images and intraoperative transoesophageal echocardiography guidance helped to determine the positions of the inflow and pump.

This investigation was aimed to identify gene profiles in human atrial myocardium in response to chronic mechanical stretch. Right atrial appendages from 21 patients were divided into 2 groups based on the size of right atrial volume. The microarray DATA analyses differentially identified 335 genes (> 2.0-fold, corrected P

L’article prend comme sujet une fresque, représentant cinq saints nimbés, qui couvre la longueur d’un passage qui sort de l’atrium de l’église de S. Maria Antiqua à Rome. Des particularités de l’habit ecclésiastique, l’emploi de la forme vernaculaire « sancto », et la présence de saint Blaise (dont le culte n’est arrivé à Rome qu’au milieu du xe siècle), suggèrent une date d’environ l’an 1 000. Malgré l’exécution de qualité inférieure et le mauvais état de conservation, l’oeuvre constitue un document de haute importance pour l’histoire de l’église de S. Maria Antiqua ainsi que pour l’histoire de ce coin du Forum romain pendant une période pour laquelle les documents écrits nous manquent. L’auteur fait appel aux historiens de l’art de prendre soin de documenter toutes les oeuvres d’art et non seulement celles qu’on trouve les plus intéressantes.

Patients with congenital heart disease (CHD) are prone to develop atrial and ventricular arrhythmias. Multiple factors throughout life contribute to arrhythmogenicity substrate such as (i) (longstanding) volume and/or pressure overload, (ii) scar tissue, (iii) ageing-related structural remodelling, (iv) cardiovascular risk factors and (v) tachycardia-induced remodelling. At present, it is unknown whether, and to what extent, paediatric patients with CHD have atrial or ventricular conduction disorders early in life and whether there is a correlation between duration of volume/pressure overload and extensiveness of conduction disorders. To investigate this, we initiated high-resolution intraoperative epicardial mapping in paediatric patients with CHD undergoing primary open-heart surgery.

Atrial fibrillation (AF) and stroke are inextricably connected, with classical Virchow pathophysiology explaining thromboembolism through blood stasis in the fibrillating left atrium. This conceptualization has been reinforced by the remarkable efficacy of oral anticoagulant (OAC) for stroke prevention in AF. A number of observations showing that the presence of AF is neither necessary nor sufficient for stroke, cast doubt on the causal role of AF as a villain in vascular brain injury (VBI). The requirement for additional risk factors before AF increases stroke risk; temporal disconnect of AF from a stroke in patients with no AF for months before stroke during continuous ECG monitoring but manifesting AF only after stroke; and increasing recognition of the role of atrial cardiomyopathy and atrial substrate in AF-related stroke, and also stroke without AF, have led to rethinking the pathogenetic model of cardioembolic stroke. This is quite separate from recognition that in AF, shared cardiovascular risk factors can lead both to non-embolic stroke, or emboli from the aorta and carotid arteries. Meanwhile, VBI is now expanded to include dementia and cognitive decline: research is required to see if reduced by OAC. A changed conceptual model with less focus on the arrhythmia, and more on atrial substrate/cardiomyopathy causing VBI both in the presence or absence of AF, is required to allow us to better prevent AF-related VBI. It could direct focus towards prevention of the atrial cardiomyopathy though much work is required to better define this entity before the balance between AF as villain or bystander can be determined.

The use of minimally invasive transcranial ports for the resection of deep-seated lesions has been shown to be safe and effective. To date, most of the literature regarding the tubular retractors used in brain surgery is comprised of individual case reports that describe the successful resection of deep-seated lesions such as thalamic pilocytic astrocytomas, colloid cysts in the third ventricle, hematomas, and cavernous angiomas. The authors describe their experience using a tubular retractor system with three different cases involving large intraventricular meningiomas and examine radiographic and patient outcomes. A single-institution, retrospective case series was performed from a skull base database. Patients who underwent resection of intraventricular > 4-cm meningiomas with port technology were identified. The authors reviewed three cases to illustrate the feasibility of minimal access port surgery for the resection of these lesions. Complete resection was achieved in all cases. None of the patients developed permanent neurological deficits. There were no major complications related to surgery and no mortalities. Good clinical and surgical outcomes for atrium meningiomas can be achieved through the minimally invasive port technique and tumor size does not appear to be a limitation.

Objective Ventriculoatrial shunt (VAS) remains an alternate option for treatment of hydrocephalus in patients with ventriculoperitoneal shunt (VPS) failure. Unfamiliar anatomy for a neurosurgeon has resulted in the VAS falling out of favor as a treatment option. However, there are unsatisfactory reports on the long-term result of VPS, and VAS has been recently re-evaluated. We are to report the simple way to do the VAS using a peel-away sheath in a hybrid operation room. Methods A jugular vein path was drawn by ultrasound, a small incision was made above the clavicle, and a shunt catheter was tunneled into it. The jugular vein was punctured beside the tunneled catheter with a Seldinger needle under ultrasound guidance. A flexible guide wire was introduced into the vein and 6-Fr peel-away sheath was advanced into the vein along the wire. Under fluoroscopic guidance, the catheter was cut to position approximately mid-level in the atrium. After the guide wire was removed, the distal shunt catheter was passed down. After confirming proper position of the distal catheter under the fluoroscope, the catheter-guiding sheath was pulled out as a peeling-away manner. We performed this surgical procedures in 5 cases. Results All the procedures of the VAS using a peel-away sheath were performed in a hybrid operation room Of 5 patients, 3 patients had the distal catheter failures in the peritoneal cavity and 2 patients had shunt A distal catheter was successfully indwelling in all the cases without any difficulties. After the surgery, neither shunt infection nor thromboembolic event happened. Conclusion VAS using fluoroscopy and a peel-away sheath is a good alternative option for hydrocephalus patients with shunt failure related to peritoneal cavity complications.

Background Although they are at lower risk, patients with previous extracardiac conduit (EC) Fontan still may require catheter ablation for supraventricular arrhythmia. Objective The purpose of this study was to determine the optimal approach to pulmonary venous atrium (PVA) access after EC Fontan operation. Methods All electrophysiological procedures requiring PVA over a 10-year period at the UCLA Medical Center were reviewed. PVA was grouped by transcaval cardiac puncture (TCP) or direct conduit puncture. Procedural characteristics and outcomes were compared. Results Between June 2009 and November 2019, 23 electrophysiological procedures requiring PVA access were performed in 17 EC Fontan patients (53% male; median age 25 years; interquartile range 11–34). Cavoatrial overlap was identified in 14 patients by preprocedural imaging (10 cardiac computed tomography, 4 cardiac magnetic resonance). PVA access was obtained via TCP in 11, direct conduit puncture in 6, pre-existing fenestration in 5, and pulmonary artery puncture in 1. Time to PVA was significantly shorter for TCP vs direct conduit puncture (0.2 vs 1.1 hours, respectively; P = .03). The only predictor of successful TCP was the length of cavoatrial overlap by preprocedural imaging (14 vs 3 mm; P = .02). No procedural complications occurred. No change in oxygen saturation was noted, and no evidence of residual shunting was detected by follow-up echocardiography. Conclusion TCP is feasible in most patients after EC Fontan surgery and can be predicted by preprocedural advanced imaging. TCP is associated with shorter time to PVA and was uncomplicated in this single-center study. Preoperative assessment of cavoatrial overlap should be considered before catheter ablation for EC Fontan.

Background: Atrial fibrillation (AF) is the most common heart rhythm disorder in adults and a major cause of stroke. Unfortunately, current treatments of AF are suboptimal because they are not targeted to the molecular mechanisms underlying AF. Using a highly novel gene therapy approach in a canine, rapid atrial pacing model of AF, we demonstrate that NADPH oxidase 2 (NOX2) generated oxidative injury causes upregulation of a constitutively active form of acetylcholine-dependent K + current ( I KACh ), called I KH ; this is an important mechanism underlying not only the genesis, but also the perpetuation of electric remodeling in the intact, fibrillating atrium. Methods: To understand the mechanism by which oxidative injury promotes the genesis and maintenance of AF, we performed targeted injection of NOX2 short hairpin RNA (followed by electroporation to facilitate gene delivery) in atria of healthy dogs followed by rapid atrial pacing. We used in vivo high-density electric mapping, isolation of atrial myocytes, whole-cell patch clamping, in vitro tachypacing of atrial myocytes, lucigenin chemiluminescence assay, immunoblotting, real-time polymerase chain reaction, immunohistochemistry, and Masson trichrome staining. Results: First, we demonstrate that generation of oxidative injury in atrial myocytes is a frequency-dependent process, with rapid pacing in canine atrial myocytes inducing oxidative injury through the induction of NOX2 and the generation of mitochondrial reactive oxygen species. We show that oxidative injury likely contributes to electric remodeling in AF by upregulating I KACh by a mechanism involving frequency-dependent activation of PKC ε (protein kinase C epsilon). The time to onset of nonsustained AF increased by >5-fold in NOX2 short hairpin RNA–treated dogs. Furthermore, animals treated with NOX2 short hairpin RNA did not develop sustained AF for up to 12 weeks. The electrophysiological mechanism underlying AF prevention was prolongation of atrial effective refractory periods, at least in part attributable to the attenuation of I KACh . Attenuated membrane translocation of PKC ε appeared to be a likely molecular mechanism underlying this beneficial electrophysiological remodeling. Conclusions: NOX2 oxidative injury (1) underlies the onset, and the maintenance of electric remodeling in AF, as well, and (2) can be successfully prevented with a novel, gene-based approach. Future optimization of this approach may lead to a novel, mechanism-guided therapy for AF.

Cardiac morphogenesis requires an intricate orchestration of mechanical stress to sculpt the heart as it transitions from a straight tube to a multichambered adult heart. Mechanical properties are fundamental to this process, involved in a complex interplay with function, morphology, and mechanotransduction. In the current work, we propose a pressurization technique applied to the zebrafish atrium to quantify mechanical properties of the myocardium under passive tension. By further measuring deformation, we obtain a pressure-stretch relationship that is used to identify constitutive models of the zebrafish embryonic cardiac tissue. Two-dimensional results are compared with a three-dimensional finite element analysis based on reconstructed embryonic heart geometry. Through these steps, we found that the myocardium of zebrafish results in a stiffness on the order of 10 kPa immediately after the looping stage of development. This work enables the ability to determine how these properties change under normal and pathological heart development.

Background Clinical studies have reported that epicardial adipose tissue (EpAT) accumulation associates with the progression of atrial fibrillation (AF) pathology and adversely affects AF management. The role of local cardiac EpAT deposition in disease progression is unclear, and the electrophysiological, cellular, and molecular mechanisms involved remain poorly defined. Objectives The purpose of this study was to identify the underlying mechanisms by which EpAT influences the atrial substrate for AF. Methods Patients without AF undergoing coronary artery bypass surgery were recruited. Computed tomography and high-density epicardial electrophysiological mapping of the anterior right atrium were utilized to quantify EpAT volumes and to assess association with the electrophysiological substrate in situ. Excised right atrial appendages were analyzed histologically to characterize EpAT infiltration, fibrosis, and gap junction localization. Co-culture experiments were used to evaluate the paracrine effects of EpAT on cardiomyocyte electrophysiology. Proteomic analyses were applied to identify molecular mediators of cellular electrophysiological disturbance. Results Higher local EpAT volume clinically correlated with slowed conduction, greater electrogram fractionation, increased fibrosis, and lateralization of cardiomyocyte connexin-40. In addition, atrial conduction heterogeneity was increased with more extensive myocardial EpAT infiltration. Cardiomyocyte culture studies using multielectrode arrays showed that cardiac adipose tissue-secreted factors slowed conduction velocity and contained proteins with capacity to disrupt intermyocyte electromechanical integrity. Conclusions These findings indicate that atrial pathophysiology is critically dependent on local EpAT accumulation and infiltration. In addition to myocardial architecture disruption, this effect can be attributed to an EpAT-cardiomyocyte paracrine axis. The focal adhesion group proteins are identified as new disease candidates potentially contributing to arrhythmogenic atrial substrate.

Background Atrial flow regulator (AFR) (Occlutech, Helsingborg, Sweden) are self-expanding, circular devices. A flexible waist in the centre connects the two discs and has a centrally located shunt. Case summary We report a case of an 80-year-old woman undergoing a repeat left atrial ablation for persistent atrial fibrillation with an implanted AFR. The AFR was implanted 1 year prior to the procedure for heart failure with preserved ejection fraction as part of the AFR-PRELIEVE trial. A single, fluoroscopy-guided, transseptal puncture was performed infero-posterior to the device, allowing the positioning of the mapping (LASSO® 20 mm, Biosense Webster, Irvine, CA, USA) and ablation (Thermocool Smarttouch SF, CARTO®, Biosense Webster, Irvine, CA, USA) catheter in the left atrium. Three-dimensional mapping (CARTO®, Biosense Webster, Irvine, CA, USA) and left atrial ablation were successfully performed. After the procedure, fluoroscopy and transthoracic echocardiography showed an unchanged device position. Discussion To our knowledge, this is the first case report of a transseptal puncture in a patient with an implanted AFR. Transseptal puncture in patients with an implanted AFR seems to be safe and feasible. With device diameters of 21–23 mm and based on previous studies on similar devices, transseptal puncture should be possible in most patients, as opposed to puncture through the device.

The presence of tumor thrombus extending into the inferior vena cava (IVC) is a rare complication of hepatocellular carcinoma (HCC), presenting in only 3.8% of patients, resulting in a median survival of 1.9 months. Even rarer and likely with worse outcomes is a tumor extending from the IVC into the right atrium and ventricle. Here we present the case of a 55-year-old male with advanced liver cirrhosis from nonalcoholic steatohepatitis (NASH) with a diagnosis of HCC and IVC tumor thrombus invading into the right atrium and ventricle. The patient was treated with stereotactic body radiotherapy (SBRT) to 30Gy in 5 fractions delivered over 5 days targeting the right atrium, right ventricle and the outflow tract. Initially, the patient had a radiographic and clinical response to treatment, with minimal acute toxicities. Unfortunately, due to declining liver function, the patient subsequently entered hospice care and died 4 months posttreatment. This case demonstrates the poor prognosis of this advanced presentation of disease but suggests that SBRT is a safe and reasonable treatment approach for the reduction of IVC and cardiac tumor thrombus in HCC.