Optimal atrioventricular delay in CRT patients can be approximated using surface electrocardiography and device electrograms.

Unlabelled: Electrocardiographic AV Delay Adjustment.

Background: Optimization of the atrioventricular (AV) delay (AVD) may result in an improvement in cardiac resynchronization therapy (CRT) outcome. Previous studies have shown positive correlation between interatrial conduction time measured invasively during the implant procedure and optimal AVD determined postimplant using Doppler echocardiography.

High risk of ventricular arrhythmias in patients with nonischemic dilated cardiomyopathy presenting with syncope.

It is not entirely clear whether the presentation of syncope in patients with nonischemic dilated cardiomyopathy (NIDC) is an ominous prognostic indicator, because randomized controlled implantable cardioverter-defibrillator (ICD) trials generally exclude such patients. This study compared 108 consecutive patients with NIDC presenting with syncope with 71 consecutive patients with NIDC who presented with sustained ventricular arrhythmias, with regard to freedom from any ventricular arrhythmias or life-threatening arrhythmias and all-cause mortality. There was no significant difference between the groups in the 3 outcomes during the follow-up of 43.

[Mechanism of cardiac resynchronization therapy by real-time three-dimensional echocardiography in patients with heart failure].

We report the case of a 66-year-old man with heart failure NYHA class IV treated with biventricular pacing for cardiac resynchronization. The patient was evaluated by real-time three-dimensional transthoracic echocardiography before and 48 hours after pacemaker implantation. The use of three-dimensional echocardiography contributed to understanding the underlying mechanism involved in cardiac resynchronization therapy by demonstrating enhanced synchrony of myocardial segments, which resulted in the patient's clinical improvement.

Echocardiographic evidence of left atrial abnormality in young patients with lone paroxysmal atrial fibrillation.

Usual assessment of left atrial size by 2-dimensional echocardiography in the anteroposterior dimension often underestimates the true atrial size. We compared 15 young patients (< or =50 years old) with lone paroxysmal atrial fibrillation to age-matched controls, and measured atrial size in the inferosuperior and mediolateral dimensions. These additional measurements and atrial volumes were significantly increased compared with control patients, revealing that patients with apparent "lone" paroxysmal atrial fibrillation may have subtle structural abnormalities of the left atrium.