Predictors of response to cardiac resynchronization therapy--importance of left ventricular dyssynchrony.

Background: Cardiac resynchronization therapy (CRT) is currently used in selected patients with dilated cardiomyopathy and heart failure. However, 30% of patients do not respond to CRT when selection is based on clinical and electrocardiographic criteria. Left ventricular dyssynchrony can be evaluated by tissue Doppler imaging and it has been described as a useful precdictor of response to CRT.

Cardiac resynchronization therapy with sequential biventricular pacing: impact of echocardiography guided VV delay optimization on acute results.

Background: Cardiac resynchronization therapy (CRT) improves left ventricular synchrony as evaluated by tissue Doppler imaging (TDI), leading to improved left ventricular performance and reverse remodeling. New CRT devices enable programming of left and right VV delay. The aim of this study was to determine whether sequential biventricular (BiV) pacing by echo-guided programming of VV delay would enhance the response to CRT.

Transesophageal echocardiography-guided cardioversion of atrial fibrillation. Selection of a low-risk group for immediate cardioversion.

Introduction: In patients (pts) with atrial fibrillation (AF) of more than 48 hours' duration, electrical cardioversion (ECV) should only be performed after 3 weeks of effective anticoagulation. Transesophageal echocardiography (TEE) allows earlier ECV; however, despite exclusion of thrombi in the atrium and left atrial appendage (LAA), cases of thromboembolism related to ECV have been documented in AF. To define a low-risk group for cardioversion without previous anticoagulation, pts were selected for immediate ECV if no thrombi or dynamic spontaneous echo contrast (auto-contrast) were found after TEE and if LAA velocity was more than 0.

Tissue Doppler echocardiography for evaluation of patients with ventricular resynchronization therapy.

Introduction And Objective: Ventricular resynchronization therapy optimizes cardiac function and induces reverse remodeling of the left ventricle (LV) in patients (pts) with dilated cardiomyopathy and intraventricular conduction disturbances. Improvement of LV mechanical synchrony seems to be the predominant mechanism. There is a growing interest in objective quantification of desynchronization.

Effects of cardiac resynchronization therapy on right ventricular function--evaluation with tissue Doppler echocardiography.

Introduction And Objective: Ventricular resynchronization therapy improves cardiac function in patients (pts) with dilated cardiomyopathy and intraventricular conduction disturbances. The effects of ventricular resynchronization on right ventricular function have been poorly studied. Tricuspid annular motion can be studied with tissue Doppler echocardiography, which enables quantitative assessment of right ventricular function.