Impact of catheter ablation of the coronary sinus on paroxysmal or persistent atrial fibrillation.

Objectives: This study evaluated the impact of catheter ablation of the coronary sinus (CS) region during paroxysmal and persistent atrial fibrillation (AF).

Background: The CS musculature and connections have been implicated in the genesis of atrial arrhythmias.

Methods: Forty-five patients undergoing catheter ablation of AF were studied.

Outcome after implantation of a cardioverter-defibrillator in patients with Brugada syndrome: a multicenter study.

Background: Brugada syndrome is an arrhythmogenic disease characterized by an increased risk of sudden cardiac death (SCD) by ventricular fibrillation. At present, an implantable cardioverter-defibrillator (ICD) is the recommended therapy in high-risk patients. This multicenter study reports the outcome of a large series of patients implanted with an ICD for Brugada syndrome.

Effects of right, left, and biventricular pacing on myocardial perfusion in ischemic conditions.

Objectives: In normal hearts, the distribution of regional myocardial perfusion is altered by ventricular pacing. Little is known about the impact of ventricular pacing on regional myocardial perfusion in ischemic conditions. In this acute echocardiographic study, we compared the respective effects of right ventricular pacing (RVP), left ventricular pacing (LVP), and biventricular pacing (BVP) on regional perfusion in a swine model of graded ischemia.

Dynamic ventricular dyssynchrony: an exercise-echocardiography study.

Objectives: We sought to assess the effects of exercise on ventricular dyssynchrony in patients with normal and depressed left ventricular (LV) function.

Background: Asynchronous myocardial contraction adversely influences ventricular function and is associated with a poor prognosis in heart failure. Exercise-induced changes in ventricular dyssynchrony may be an important determinant of dynamic changes in cardiac output and mitral regurgitation.

Echocardiographic assessment during exercise of heart failure patients with cardiac resynchronization therapy.

This prospective echocardiographic study investigated the respective impacts of left ventricular (LV) pacing and simultaneous and sequential biventricular pacing (BVP) on ventricular dyssynchrony during exercise in 23 patients with compensated heart failure and ventricular conduction delays. During exercise, LV pacing and BVP significantly (p <0.05) improved mitral regurgitation and LV dyssynchrony compared with spontaneous activation.

Flutter localized to the anterior left atrium after catheter ablation of atrial fibrillation.

Introduction: Organized atrial arrhythmias following atrial fibrillation (AF) ablation are typically due to recovered pulmonary vein (PV) conduction or reentry at incomplete ablation lines. We describe the role of nonablated anterior left atrium (LA) in arrhythmias observed after AF ablation.

Methods: A total of 275 consecutive patients with paroxysmal (n = 200) or chronic (n = 75) AF had PV isolation with/without additional linear ablation at the mitral isthmus (n = 106), LA roof (n = 23), or both (n = 88).

[Identification of candidates for multisite pacing: results and presumed mechanisms of action after five years experience].

Biventricular resynchronisation is an additional therapeutic option in the management of refractory heart failure, with a functional and haemodynamic benefit as well as an improved morbidity and mortality. However, the rate of non-responsive patients has prompted a re-think about the presumed mechanisms of action for this procedure. This study aims to identify candidates more successfully.

Localized sources maintaining atrial fibrillation organized by prior ablation.

Background: Endocardial mapping of localized sources driving atrial fibrillation (AF) in humans has not been reported.

Methods And Results: Fifty patients with AF organized by prior pulmonary vein and linear ablation were studied. AF was considered organized if mapping during AF showed irregular but discrete atrial complexes exhibiting consistent activation sequences for >75% of the time using a 20-pole catheter with 5 radiating spines covering 3.

Catheter ablation of long-lasting persistent atrial fibrillation: clinical outcome and mechanisms of subsequent arrhythmias.

Background: Catheter ablation of atrial fibrillation (AF) is challenging in patients with long-standing persistent AF. The clinical outcome and subsequent arrhythmia recurrence after using an ablation method targeting multiple left atrial sites with the aim of achieving acute AF termination has not been characterized.

Methods: Sixty patients (mean age: 53 +/- 9 years) with persistent AF (mean duration: 17 +/- 27 months) were prospectively followed after catheter ablation.

Catheter ablation of long-lasting persistent atrial fibrillation: critical structures for termination.

Background: The relative contributions of different atrial regions to the maintenance of persistent atrial fibrillation (AF) are not known.

Methods: Sixty patients (53 +/- 9 years) undergoing catheter ablation of persistent AF (17 +/- 27 months) were studied. Ablation was performed in a randomized sequence at different left atrial (LA) regions and comprised isolation of the pulmonary veins (PV), isolation of other thoracic veins, and atrial tissue ablation targeting all regions with rapid or heterogeneous activation or guided by activation mapping.

[Catheter ablation of paroxysmal atrial fibrillation].

Unlabelled: Catheter ablation techniques for atrial fibrillation have undergone an extensive evolution, starting with linear lesions in the right, then the left atria before being superseded by ablation of triggers, mainly from the pulmonary veins. We investigate the feasibility and results of combined pulmonary vein and linear ablation utilizing a specific linear lesion connecting the lateral mitral annulus to the left inferior pulmonary vein (left isthmus).

Methods: 115 patients (101 M: 54 +/- 9 years) with paroxysmal atrial fibrillation (7 +/- 5 years) resistant to 4 +/- 1.

[Echocardiography and biventricular resynchronisation].

Biventricular resynchronisation has been recently shown to be an effective therapeutic option in patients with refractory dilated cardiomyopathy. Based on the finding of ventricular asynchrony, the aim of the method is to restore uniform contraction of the ventricular walls. However, the initial electrocardiographic criteria for selection of patients were only associated with a 70% rate of response.

[Asynchronism and right ventricular pacing].

Unlabelled: In patients with congenital heart block (CHB), dual-chamber pacing restores physiological heart rate and atrio-ventricular synchronization. However, patients with narrow QRS junctional escape rhythm may be deleteriously affected by long-term, permanent, apical ventricular pacing. We assessed the impact of apical ventricular pacing on echocardiographic ventricular dyssynchrony and hemodynamic parameters.

Biventricular pacing and left ventricular pacing in heart failure: similar hemodynamic improvement despite marked electromechanical differences.

Introduction: We conducted an acute echocardiographic study comparing hemodynamic and ventricular dyssynchrony parameters during left ventricular pacing (LVP) and biventricular pacing (BVP). We sought to clarify the mechanisms responsible for similar hemodynamic improvement despite differences in electrical activation.

Methods And Results: Thirty-three patients underwent echocardiography prior to implantation with a multisite pacing device (spontaneous rhythm [SR]) and 2 days after implantation (BVP and LVP).

Detrimental ventricular remodeling in patients with congenital complete heart block and chronic right ventricular apical pacing.

Background: Although dual-chamber pacing improves cardiac function in patients with complete congenital atrioventricular block (CCAVB) by restoring physiological heart rate and atrioventricular synchronization, the long-term detrimental effect of asynchronous electromechanical activation induced by apical right ventricular pacing (RVP) has not been well clarified.

Methods And Results: Twenty-three CCAVB adults (24+/-3 years) with a DDD transvenous pacemaker underwent conventional echocardiography before implantation and, after at least 5 years of RVP, an exercise test and echocardiography coupled with tissue Doppler imaging and tissue tracking. They were compared with 30 matched healthy control subjects.

Echocardiographic parameters of ventricular dyssynchrony validation in patients with heart failure using sequential biventricular pacing.

Objectives: We sought to evaluate the relationship between hemodynamic and ventricular dyssynchrony parameters in patients undergoing simultaneous and sequential biventricular pacing (BVP).

Background: Various echocardiographic parameters of ventricular dyssynchrony have been proposed to screen and optimize BVP therapy.

Methods: Forty-one patients with heart failure undergoing BVP implantation were studied.

Catheter ablation for atrial fibrillation in congestive heart failure.

Background: Congestive heart failure and atrial fibrillation often coexist, and each adversely affects the other with respect to management and prognosis. We prospectively evaluated the effect of catheter ablation for atrial fibrillation on left ventricular function in patients with heart failure.

Methods: We studied 58 consecutive patients with congestive heart failure and a left ventricular ejection fraction of less than 45 percent who were undergoing catheter ablation for atrial fibrillation.

Death during polysomnography of a patient with cheyne-stokes respiration, respiratory acidosis, and chronic heart failure.

A patient with chronic heart failure and chronic respiratory failure (CRF) underwent ambulatory polysomnography at home. She was found dead on the morning after the recording. The tracings confirmed severe sleep apnea syndrome.

Chronic cor pulmonale: a rare complication of undiagnosed pacemaker lead endocarditis.

Pacemaker lead infection is a rare life-threatening complication of permanent transvenous pacing. We describe the case of a young man who suffered recurrent undiagnosed septic pulmonary embolisms from pacemaker lead vegetations inducing chronic cor pulmonale with major pulmonary arterial hypertension. The potential complications of transvenous pacing and the systematic use of transesophageal echocardiography are emphasized.

Incidence, clinical implications and prognosis of atrial arrhythmias in Brugada syndrome.

Aims: This single-centre prospective study was designed to determine the incidence, therapeutic implications and prognosis of atrial arrhythmias (AA) in patients with Brugada syndrome (BS).

Methods And Results: Fifty nine consecutive patients with BS and 31 age and gender-matched controls underwent an electrophysiological exploration and were followed-up during 34+/-13 months. The final AA incidence was 20% in BS patients vs 0% in controls (p < 0.

Comparison of permanent left ventricular and biventricular pacing in patients with heart failure and chronic atrial fibrillation: a prospective hemodynamic study.

Background: Left ventricular pacing (LVP) and biventricular pacing (BVP) have been proposed as treatments for patients with advanced heart failure complicated by discoordinate contraction due to intraventricular conduction delay. For patients in sinus rhythm, BVP works in part by modulating the electronic atrial-ventricular time delay and thus optimizing contractile synchrony, the contribution of atrial systole, and reducing mitral regurgitation. However, little is known of the mechanisms of BVP in heart failure patients with drug-resistant chronic atrial fibrillation.

Improvement of left ventricular wall synchronization with multisite ventricular pacing in heart failure: a prospective study using Doppler tissue imaging.

Unlabelled: We sought to assess right, left and biventricular pacing effects on myocardial function by using pulsed-Doppler tissue imaging (DTI) and automated border detection (ABD) techniques which provide electromechanical delay (EMD) assessment of the different left ventricular walls.

Methods: 15 patients (67+/-7 years) with drug-resistant primitive dilated cardiomyopathy and QRS> or =140 ms received a pacemaker for multisite ventricular pacing. Echocardiography was performed after 1 month of biventricular pacing (BVP).