Comprehensive left atrial appendage optimization of thrombus using surface echocardiography: the CLOTS multicenter pilot trial.

Background: The aim of this study was to determine the ability to identify thrombus within the left atrial appendage (LAA) in the setting of atrial fibrillation (AF) using transthoracic echocardiography (TTE). In AF, the structure and function of the LAA has historically been evaluated using transesophageal echocardiography (TEE). The role of TTE remains undefined.

Alterations of regional myocardial function in a swine model of myocardial infarction assessed by echocardiographic 2-dimensional strain imaging.

Background: Tissue Doppler strain and strain rate imaging have been introduced for quantitative assessment of regional myocardial function. These techniques are largely limited to the evaluation of overall longitudinal myocardial function. This study attempted to apply radial strain, circumferential strain, radial displacement, and strain-based torsion analysis to differentiating the infarct, adjacent, and remote zones in a swine model of myocardial infarction.

Contrast-enhanced tissue Doppler imaging of the left atrial appendage is a new quantitative measure of spontaneous echocardiographic contrast in atrial fibrillation.

Aims: Although left atrial appendage spontaneous echo contrast (LAASEC) is a marker of increased thromboembolic risk in atrial fibrillation, it has previously only been evaluated qualitatively. We sought to determine if an intravenous contrast echocardiographic agent combined with tissue Doppler imaging (TDI) of the LAA could accurately quantify LAA-SEC in patients with atrial fibrillation.

Methods And Results: We prospectively identified 55 patients with persistent atrial arrhythmias (mean age 63+/-13 years) undergoing a transesophageal echocardiography (TEE), with LAA-SEC prior to direct current cardioversion.

Clinical features of mixed physiology of constriction and restriction: echocardiographic characteristics and clinical outcome.

Aims: An entity of patients with mixed physiology of constriction and restriction has been reported, however, the characteristics of these patients have not been well documented. We evaluated the clinical features and the outcome of these patients.

Methods And Results: Study subjects consisted of 38 patients (57+/-14 years, 8 females, 30 males) who were diagnosed as having mixed physiology based on transthoracic and/or transesophageal echocardiography, MRI (or CT), cardiac catheterization, endomyocardial biopsy and/or surgical findings.

Relation of brachial artery reactivity to nitroglycerin and heart rate recovery following exercise in healthy male volunteers.

The parasympathetic nervous system facilitates peripheral arterial vasodilation and is also responsible for a decrease in heart rate immediately after exercise (heart rate recovery [HRR]). The relation among parasympathetic tone measured by HRR after exercise, endothelium-mediated vasodilation, and nitroglycerin-mediated vasodilation (determined with brachial artery ultrasound) was assessed in 25 healthy young men. One-minute HRR was nonsignificantly related to endothelium-mediated vasodilation (r = -0.

Safety of stress testing in patients with hypertrophic cardiomyopathy.

Two hundred sixty-three consecutive patients with hypertrophic cardiomyopathy underwent stress testing. Major complications occurred in 0.04% of patients and minor events occurred in 23%.

Conduction system abnormalities in patients with obstructive hypertrophic cardiomyopathy following septal reduction interventions.

We observed the impact of percutaneous transluminal septal myocardial ablation (PTSMA) and myectomy on the conduction system in patients with obstructive hypertrophic cardiomyopathy (HC). Septal reduction intervention is capable of eliminating the left ventricular outflow tract obstruction in patients with obstructive HC; however, conduction system abnormalities are frequent consequences of these procedures. A standard 12-lead electrocardiogram and Doppler echocardiogram were obtained in 204 patients who underwent PTSMA (n = 70) or myectomy (n = 134) before and at average of 3 months after intervention.

Use of strain imaging in detecting segmental dysfunction in patients with hypertrophic cardiomyopathy.

Background: The distribution and magnitude of left ventricular hypertrophy are not uniform in patients with hypertrophic cardiomyopathy (HCM). Previous echocardiographic studies have focused on global left ventricular function. Recently, myocardial Doppler strain (epsilon) imaging, a newly developed technique, has allowed the quantification of regional myocardial motion.

Myeloperoxidase and plasminogen activator inhibitor 1 play a central role in ventricular remodeling after myocardial infarction.

Left ventricular (LV) remodeling after myocardial infarction (MI) results in LV dilation, a major cause of congestive heart failure and sudden cardiac death. Ischemic injury and the ensuing inflammatory response participate in LV remodeling, leading to myocardial rupture and LV dilation. Myeloperoxidase (MPO), which accumulates in the infarct zone, is released from neutrophils and monocytes leading to the formation of reactive chlorinating species capable of oxidizing proteins and altering biological function.

Contrast and harmonic imaging improves accuracy and efficiency of novice readers for dobutamine stress echocardiography.

Background: Newer contrast agents as well as tissue harmonic imaging enhance left ventricular (LV) endocardial border delineation, and therefore, improve LV wall-motion analysis. Interpretation of dobutamine stress echocardiography is observer-dependent and requires experience. This study was performed to evaluate whether these new imaging modalities would improve endocardial visualization and enhance accuracy and efficiency of the inexperienced reader interpreting dobutamine stress echocardiography.

Impact of left ventricular outflow tract area on systolic outflow velocity in hypertrophic cardiomyopathy: a real-time three-dimensional echocardiographic study.

Objectives: The aim of this study was to use real-time three-dimensional echocardiography (3DE) to investigate the quantitative relation between minimal left ventricular (LV) outflow tract area (A(LVOT)) and maximal LV outflow tract (LVOT) velocity in patients with hypertrophic obstructive cardiomyopathy (HCM).

Background: In patients with HCM, LVOT velocity should change inversely with minimal A(LVOT) unless LVOT obstruction reduces the pumping capacity of the ventricle.

Methods: A total of 25 patients with HCM with systolic anterior motion (SAM) of the mitral valve leaflets underwent real-time 3DE.

Doppler-derived myocardial systolic strain rate is a strong index of left ventricular contractility.

Background: Myocardial fiber strain is directly related to left ventricular (LV) contractility. Strain rate can be estimated as the spatial derivative of velocities (dV/ds) obtained by tissue Doppler echocardiography (TDE). The purposes of the study were (1) to determine whether TDE-derived strain rate may be used as a noninvasive, quantitative index of contractility and (2) to compare the relative accuracy of systolic strain rate against TDE velocities alone.