BACKGROUND Cardiac Resynchronization Therapy (CRT) leads to a reduction of left-ventricular dyssynchrony and an acute and sustained hemodynamic improvement in patients with chronic heart failure. Furthermore, an optimized AV-delay leads to an improved myocardial performance in pacemaker patients. The focus of this study is to investigate the acute effect of an optimized AV-delay on parameters o...

SEE PAGE 642 T he pressure overload of pulmonary arterial hypertension (PAH) predisposes the right ventricle (RV) to hypertrophy, dilation, and reduced pump function. Alterations in RV functional indexes such as tricuspid annular plane excursion, fractional area change, and tissue Doppler myocardial velocity have been shown to have prognostic significance in PAH (1). With the advent of strain a...

A 4-year-old Hispanic male presented with an isolated episode of vomiting and syncope. The clinical history was otherwise unremarkable, and he appeared well on clinical examination. His initial resting ECG demonstrated ST-segment abnormalities and increased voltages; there was no ventricular preexcitation (Figure 1A). Transthoracic echocardiography revealed marked dyskinesis of the basal interv...

BACKGROUND Electrocardiographic imaging (ECGI) is a method for noninvasive epicardial electrophysiologic mapping. ECGI previously has been used to characterize the electrophysiologic substrate and electrical synchrony in a very heterogeneous group of patients with varying degrees of coronary disease and ischemic cardiomyopathy. OBJECTIVE The purpose of this study was to characterize the left ...

BACKGROUND Chronic right ventricular apical (RVA) pacing has been associated with increased risk of heart failure and adverse outcome. The acute effects of RVA pacing on three-dimensional (3D) ventricular function and mechanical dyssynchrony are not well known. We performed a real-time 3D echocardiographic (RT3DE) study to assess global and regional left ventricular function during RVA pacing. ...

Left ventricular dyssynchrony can be assessed with phase parameters from radionuclide ventriculography (RNVG), including approximate entropy (ApEn). The input values used to calculate ApEn will affect the results significantly, so it is essential optimise for application. However date, no optimisation applied images has been published. In this paper, generated data were simulate patient images,...

BACKGROUND The effect of b-blockage on cardiac dyssynchrony in idiopathic dilated cardio-myopathy (IDC) is unknown. This study evaluated the impact of carvedilol and metoprolol succinate on left ventricular (LV) dyssynchrony and reverse remodeling in IDC. METHODS In this small, prospective, double-blind study, we randomly assigned 81 IDC patients to receive carvedilol or metoprolol succinate....

Left ventricular (LV) systolic torsion is a primary mechanism contributing to stroke volume (SV). We hypothesized that change in LV torsion parallels changes in global systolic performance during dyssynchrony and cardiac resynchronization therapy (CRT). Seven anesthetized open chest dogs had LV pressure-volume relationship. Apical, basal, and mid-LV cross-sectional echocardiographic images were...

BACKGROUND Disease progression and heart failure development in Ebstein's Anomaly (EA) of the tricuspid valve is characterized by both right and left ventricular (LV) deterioration. The mechanisms underlying LV dysfunction and their role in heart failure development are incompletely understood. We hypothesized that LV dyssynchrony and impaired torsion and recoil mechanics induced by paradoxical...

AIMS Cardiac resynchronization therapy (CRT) has recently emerged as an effective treatment for patients with moderate-to-severe systolic heart failure and left bundle branch block (LBBB). Right ventricular pacing (RVP) leads to an LBBB-like pattern in the electrocardiogram. The aim of this study was to evaluate the frequency of ventricular mechanical dyssynchrony in patients induced by RVP. ...