A 79-year-old woman with severe aortic stenosis underwent aortic valve replacement surgery, and had ligation of the left atrial appendage (LAA) using an epicardial approach. On a post-operative echocardiographic evaluation, the distal portion of the LAA was excluded, leaving no communication with the left atrium. The proximal portion of the ...

Supraventricular tachycardia (SVT) was observed in a 13-year-old male patient with complex clinical features that included univentricular heart with single atrium, pulmonary atresia, and polysplenia syndrome. During electrophysiologic study, atrial burst stimuli reproducibly induced and terminated the SVT, while the occurrence of ventriculoatrial block did not interrupt the SVT. His ...

BACKGROUND: Symptomatic prolonged sinus pauses upon termination of atrial fibrillation (AF) are an indication for pacemaker implantation. METHODS AND RESULTS: We evaluated the clinical outcomes of 4 patients who showed prolonged sinus pauses (> 2 seconds) upon termination of AF and thus underwent ablation. The ablative procedure included pulmonary vein ...

BACKGROUND: Pulmonary vein stenosis (PVS) has been described as a complication after primary catheter ablation of atrial fibrillation (Afib). The purpose of this study was to evaluate the utility of transesophageal echocardiography (TEE) as follow-up tool after catheter ablation of Afib and interventional therapy of PVS and pulmonary vein occlusion ...

We detail findings in a patient with incessant idiopathic left ventricular tachycardia (ILVT), induced cardiomyopathy, and an "electrical storm" consisting of recurrent polymorphic ventricular tachycardia (PVT). Catheter ablation not only eradicated the ILVT, but also additionally suppressed recurrent PVT. These findings suggest that the recurrent PVT storm in this patient ...

The interplay between left atrial (LA) dilatation and atrial fibrillation (AF) has been well established, but the underlying mechanisms of this vicious circle are not fully understood. Recent studies indicated that pulmonary vein (PV) dilatation is implicated in the development of AF. On the other hand, PV dilatation has been ...

BACKGROUND: Wide electrical pulmonary vein isolation (PVI) with two separate rings of ablation requires extensive ablation on the posterior left atrial wall close to the esophagus. OBJECTIVE: The purpose of this study was to determine the feasibility of PVI using a single ring of radiofrequency ablation lesions. METHODS: Irrigated-tip ablation ...

INTRODUCTION: Intracardiac delay optimization of biventricular and dual-chamber pacing devices currently relies on time-consuming echocardiographic measurements. A novel intracardiac electrogram (IEGM) method for atrioventricular (AV/PV) and interventricular (VV) delay optimization was developed, which can be performed during routine device follow-up. METHODS AND RESULTS: In this prospective, nonrandomized, multi-center trial, patients ...

Atrial fibrillation (AF) is a common cardiac rhythm disturbance and its incidence is increasing. Radiofrequency catheter ablation (RFCA) is a highly successful therapy for treating AF, and its use is becoming more widespread; however, with its increasing use and evolving technique, known complications are better understood and new complications are ...

Crista terminalis is a fibromuscular ridge at the posterolateral region of the right atrium (RA). Superiorly localized prominent crista terminalis can mimic pathologic RA mass on transthoracic echocardiograms. Transesophageal echocardiography can be used to differentiate nonpathologic structures from pathologic ones. Besides mimicking RA mass, crista terminalis is an important anatomic ...

BACKGROUND: Linear microwave ablation has been shown to be effective for treatment of atrial fibrillation during open-heart surgery by producing transmural lesions in the atrium to isolate the pulmonary veins. However, the safety and efficacy of percutaneous, transcatheter, linear microwave ablation for atrial arrhythmias, while demonstrated in animal models, is ...

The voltage-gated potassium (Kv) channel Kv1.5 mediates the I(Kur) repolarizing current in human atrial myocytes and regulates vascular tone in multiple peripheral vascular beds. Understanding the complex regulation of Kv1.5 function is of substantial interest because it represents a promising pharmacological target for the treatment of atrial fibrillation and hypoxic ...

Regular left atrial tachycardias are a frequent complication of atrial fibrillation ablation procedures. The arrhythmia mechanism appears to be due to focal pulmonary vein reentry in patients who undergo only electrically guided pulmonary vein isolation. The most common site of origin is the septal and inferior aspect of the right ...

BACKGROUND: The accuracy of three-dimensional mapping systems is affected by cardiac contraction and respiration. OBJECTIVE: The study sought to determine relative motion of cardiac and thoracic structures to assess positional errors and guide the choice of an optimized spatial reference. METHODS: Motion of catheters placed at the coronary sinus (CS), ...

Atrial transseptal puncture as a means of accessing the left heart is a critical component of catheter ablation procedures for atrial fibrillation, left-sided accessory pathways, and access to the left ventricle in patients with certain types of prosthetic aortic valves. Although this technique has been performed successfully since the 1950s, ...

BACKGROUND: Interatrial conduction occurs via discrete pathways along the coronary sinus musculature, fossa ovalis region, and Bachman's bundle. We assessed the feasibility of altering interatrial conduction by selectively ablating two of these conduction pathways using a novel mesh electrode ablation catheter. METHODS: Circular radiofrequency energy catheter ablation lesions were created ...

Pulmonary vein (PV) arrhythmogenicity underlying the maintenance of atrial fibrillation (AF) may be explained by three mechanisms: enhanced automaticity, triggered activity, and reentry. There are only a few reports describing sustained PV tachycardias (PVT) following electrical disconnection from the left atrium, in which the electrophysiological features are most consistent with ...

Atrial septostomy or septectomy are required to enable atrial mixture in various congenital cardiac lesions. The aim of this article was to introduce a technique where atrial septostomy application could be employed off pump with the aid of a new device. To our knowledge this is the first report for ...

Abnormal atrial depolarization, denoted as interatrial block (IAB; P wave >110 ms), is associated with myocardial ischemia during exercise. The authors conducted an 18-month follow-up for cardiovascular events in 31 consecutive patients with IAB and 60 controls without IAB at rest; participants had coronary artery disease and hypertension and had ...

The principles of Fontan conversion with arrhythmia surgery are to restore the cardiac anatomy by converting the original atriopulmonary connection to a total cavopulmonary artery extracardiac connection and treat the underlying atrial arrhythmias. Successful outcomes of this procedure are dependent on a thorough understanding of several factors: the patient's fundamental ...

Complete atrioventricular block, second-degree Mobitz type II and first-degree atrioventricular block with right bundle branch block were observed consecutively following successful radiofrequency ablation in close proximity to the sinus node. This resulted in the modification and disappearance of the inappropriate sinus tachycardia that had previously been present. Neither tachycardia nor ...

BACKGROUND: New imaging strategies for atrial fibrillation (AF) ablation should enhance the safety of this technique. The role of transesophageal echocardiography (TEE) in this setting has not been prospectively evaluated. METHODS: Under general anesthesia, 85 patients underwent TEE-guided AF ablation. A hybrid technique was performed with circular pulmonary veins (PV) ...

INTRODUCTION: High-density three-dimensional (3D) mapping of the pulmonary vein (PV)-left atrial (LA) junction was performed to characterize spontaneous PV activity in humans. METHODS AND RESULTS: The activation patterns of ectopic beats and of the initial 2 seconds of atrial fibrillation (AF) from the PVs were analyzed using a 64-poles basket ...

BACKGROUND: A 34-year-old woman with known familial pulmonary arterial hypertension presented with syncope. Despite medical therapy with an endothelin-receptor antagonist and a phosphodiesterase inhibitor, the patient had NYHA class III symptoms, with exertional dyspnea. Right heart catheterization revealed severe pulmonary hypertension (right atrial pressure 15 mmHg, right ventricular pressure 80/15 ...

Recent advances in the study of cardiac development have shown the relevance of addition of myocardium to the primary myocardial heart tube. In wild-type mouse embryos (E9.5-15.5), we have studied the myocardium at the venous pole of the heart using immunohistochemistry and 3D reconstructions of expression patterns of MLC-2a, Nkx2.5, ...

Atrial tachyarrhythmias are a very common cardiovascular disease in clinical practice with an incidence that doubles with each advancing decade. A key issue to understand their pathophysiological mechanisms is the analysis and interpretation of atrial electrograms (AEG). To properly study these signals, ventricular artifacts have to be removed from the ...

BACKGROUND: Multiple cardiac ganglia are present in the left atrial (LA) region, and marked changes in autonomic nervous activity can occur after left atrial catheter ablation (CA) for atrial fibrillation (AF). Vasospastic angina involving the inferior wall of the left ventricle has been reported as a complication shortly after LACA. ...

The thoracic veins are important foci for the genesis of ectopic atrial tachycardia and play a critical role in the pathophysiology of paroxysmal and permanent atrial fibrillation. The pulmonary veins have the highest arrhythmogenic activity and other venous structures (eg, superior vena cava, coronary sinus and ligament of Marshall) have ...

BACKGROUND: Transesophageal echocardiography (TEE) is regarded as the method of choice for imaging left atrial appendage thrombi (LAAT). However, the interobserver variability among 2 independent echocardiographic laboratories in diagnosing LAAT by multiplane TEE has not yet been assessed. METHODS AND RESULTS: The videorecordings of 50 patients in atrial fibrillation (25 ...

BACKGROUND: Pulmonary vein stenosis is a recognized complication of catheter ablation of arrhythmias emanating from the pulmonary vein; however, there is little information on secondary effects of pulmonary vein stenosis on lung tissue. METHODS AND RESULTS: A 55-year-old man with a history of paroxysmal atrial fibrillation refractory to antiarrhythmic medication ...

Curing atrial fibrillation (AF) by catheter ablation has significantly improved patient morbidity and mortality. The circumferential pulmonary vein isolation technique is established as the principal procedure, with a high cure rate and acceptable safety, for paroxysmal AF, but new adjunctive ablation strategies targeting the AF substrates and sources for long-standing ...

OBJECTIVES: We sought to investigate the short-term and midterm effects of left atrial appendage exclusion on left atrial function. Left atrial appendage exclusion is considered a possible therapeutic option for stroke prevention in patients with atrial fibrillation. Favorable outcomes have encouraged widespread use of left atrial appendage exclusion for cardiac ...

Radiofrequency catheter ablation was performed in 2 patients with atrial tachycardia (AT). In both cases the AT originated from the inferoseptal portion of the right atrium, and the cycle length was 210 ms. The surface ECG demonstrated common counterclockwise atrial flutter, probably caused by functional block in the clockwise direction ...

Phrenic Nerve Injury (PNI) has been well studied by cardiac surgeons. More recently it has been recognized as a potential complication of catheter ablation with a prevalence of 0.11 to 0.48 % after atrial fibrillation (AF) ablation. This review will focus on PNI after AF ablation. Anatomical studies have shown ...

Pulmonary vein antrum isolation offers safe and effective treatment of atrial fibrillation by eliminating the potential triggers of this arrhythmia. The pulmonary vein antra encompass, in addition to the pulmonary veins, the left atrial roof and posterior wall and, in the case of the right pulmonary vein antra, a portion ...

A 67 year old man presented with new-onset atrial flutter. He had a history of coronary artery bypass graft (CABG) surgery on two occasions. Subsequent investigation revealed the presence of a large saphenous vein graft (SVG) aneurysm compressing the right heart. We postulate that the SVG aneurysm was the precipitating ...

BACKGROUND: Based on the hypothesis that pulmonary vein isolation could result in the damage of the epicardial fat pads, this study aimed to investigated the impact of right upper pulmonary vein (RUPV) isolation on vagal innervation to atria. METHODS: Bilateral cervical sympathovagal trunks were decentralized in 6 dogs. Metoprolol was ...

BACKGROUND: Linear ablation of left atrium (LA) guided by three dimensional (3-D) electroanatomical mapping (Carto) has been used in many centres worldwide for the treatment of atrial fibrillation (AF) instead of pure anatomical approaches. There were little data about linear ablation of LA guided by Carto and double Lasso catheters ...

In 1999, Haissaguerre et al published a landmark article showing that atrial fibrillation can be initiated by electrical activity in the pulmonary veins. Not only does it appear that electrical activity in the veins initiates fibrillation, but it also may be responsible for perpetuating fibrillation. Subsequently, similar evidence has suggested ...

Rapid repetitive activities arising from pulmonary veins may initiate atrial fibrillation. The basis of these rapid repetitive activities remains unclear, but recent evidence suggests that the autonomic nervous system plays an important role in their formation. Pulmonary veins and the adjoining left atrium are highly innervated structures. This review summarizes ...

The electrophysiological properties within the pulmonary vein (PV) and PV-left atrial (LA) junction were evaluated using a basket catheter in patients with paroxysmal atrial fibrillation. The effective refractory period of the distal PV was significantly shorter than that of the PV-LA junction. The conduction delay from the distal to proximal ...

INTRODUCTION: Potentials arising in the pulmonary veins (PV) have been proposed to be a trigger of atrial fibrillation. Percutaneously, the best results for curative treatment of atrial fibrillation have been achieved by segmental or circumferential isolation of the PV. The purpose of our study was to determine the feasibility of ...

BACKGROUND: Although radiofrequency (RF) ablation within the caval veins has been increasingly used to treat a variety of atrial tachyarrhythmias, the consequences of RF ablation in the caval veins are unknown. We explored the acute and chronic angiographic and pathological effects of extensive RF ablation in the caval veins. METHODS: ...

BACKGROUND: Thrombosis is a major cause of morbidity and mortality in polycythemia vera. Hypercoagulability is principally due to hyperviscosity of the whole blood, an exponential function of the hematocrit. PV is also associated with endothelial dysfunction that can predispose to arterial disease. Reduction of the red cell mass to a ...

INTRODUCTION: A left atrioesophageal fistula is an uncommon but devastating complication that may occur during atrial fibrillation (AF) ablation, and may be due to thermal injury occurring during the radiofrequency (RF) ablation. We examined the feasibility of an esophageal cooling (ECO) method using a cooled water-irrigated intraesophageal balloon (IB). METHODS ...

Atrial fibrillation (AF) is the most common sustained arrhythmia, and treatments with anti-arrhythmia drugs (AADs) have been frustrating. Limitations of AADs prompted the development of percutaneous catheter ablation. In contrast to AADs, percutaneous catheter ablation offers the possibility of a lasting cure. The successful cure of AF by percutaneous catheter ...

BACKGROUND: Stepwise segmental pulmonary vein isolation (SPVI) and circumferential pulmonary vein isolation (CPVI) have been developed to treat patients with atrial fibrillation (AF), but the preferable approach for paroxysmal AF (PAF) has not been established. METHODS AND RESULTS: One hundred and ten patients with symptomatic PAF were randomized into a ...

BACKGROUND: Heart rate variability might predict arrhythmias after coronary artery bypass grafting. METHODS: Off-line processing of 10-min electrocardiogram recordings of consecutive patients provided R-R intervals for time domain, frequency domain, Poincaré, and point correlation analyses and subsequent association with postoperative atrial fibrillation by stepwise multivariate logistic regression. RESULTS: Of 88 ...

Recent studies suggest that pulmonary vein isolation can be an effective method of treatment for atrial fibrillation. This procedure can be performed with minimally invasive, totally endoscopic cardiac surgical techniques. We report our first successful endoscopic isolation of the pulmonary veins in a patient with paroxysmal atrial fibrillation. The procedure ...

We present 4 cases of cor triatriatum in whom the diagnosis was correctly made by 2-dimensional transthoracic echocardiography, which showed the supravalvular left atrial membrane that divides the left atrium into 2 chambers. The pulmonary veins were connected normally to the proximal left atrial chamber and the left atrial appendage ...