Noninvasive prediction of left ventricular systolic dysfunction in patients with clinically suspected heart failure using acoustic cardiography.

The signs and symptoms of systolic heart failure are frequently insensitive and nonspecific, making an accurate bedside diagnosis of left ventricular systolic dysfunction (LVSD) challenging. B-type natriuretic peptide (BNP) is often used, but is not diagnostically useful when in the indeterminate range. The authors investigated the diagnostic test characteristics of acoustic cardiographic parameters to identify patients with LVSD.

Utility of a bedside acoustic cardiographic model to predict elevated left ventricular filling pressure.

Background: The authors previously described an acoustic cardiographic model that predicted echocardiographic correlates of elevated left ventricular (LV) filling pressure. This study evaluated this bedside acoustic cardiographic model against invasive measurements of LV filling pressure.

Methods And Results: Data were prospectively obtained from 68 adults referred for right heart catheterisation.

Bedside prediction of increased filling pressure using acoustic electrocardiography.

Background: Patients presenting with acute dyspnea are often a diagnostic dilemma. A bedside tool that accurately and rapidly identifies increased left ventricular (LV) filling pressure would be helpful. We evaluated acoustic electrocardiography for this purpose.

Value of brain natriuretic peptides in primary care patients with the clinical diagnosis of chronic heart failure.

Introduction: Brain natriuretic peptide (BNP) and N-Terminal pro natriuretic peptide (NT-proBNP) are widely accepted to diagnose congestive heart failure (CHF) in the emergency room. The aim of this study was to evaluate the value of BNP and NT-proBNP to diagnose CHF in primary care.

Methods: Clinical and Doppler-echocardiographic assessment of patients referred by their general practitioner (GP) with the diagnosis of CHF.

Acoustic cardiography augments prolonged QRS duration for detecting left ventricular dysfunction.

Background: Prolonged QRS duration has been used as a marker for left ventricular (LV) systolic dysfunction (SD) and is used in the evaluation of patients presenting with known or suspected heart failure. The goal of this study was to compare the abilities of QRS duration and simultaneous digital ECG and heart sounds, that is acoustic cardiographic, parameters to identify patients with LV dysfunction.

Methods: Our learning population consisted of 171 patients with possible chronic compensated or mildly decompensated heart failure who presented to an ambulatory cardiology clinic for echocardiographic examination.

Usefulness of acoustic cardiography to resolve ambiguous values of B-type natriuretic Peptide levels in patients with suspected heart failure.

B-type natriuretic peptide (BNP) levels are helpful to diagnose left ventricular (LV) systolic and/or diastolic dysfunction. BNP levels that are only moderately increased have limited diagnostic ability, and an additional test to resolve this problem would be desirable. The hypothesis that acquiring combined electrocardiographic and electronic cardiac acoustical data can improve the detection of LV dysfunction in patients with nondiagnostic values of BNP was tested.

Systolic dysfunction: correlation of acoustic cardiography with Doppler echocardiography.

For detection of left ventricular (LV) systolic dysfunction in the outpatient setting, simultaneous electrocardiographic and heart sound data have been shown to be helpful. In 161 patients with suspected or known cardiac disease, echocardiography and acoustic cardiography were performed. Acoustic cardiographic parameters correlated to echocardiography included: presence or absence of S3, electromechanical activation time (EMAT), LV systolic time (LVST), and EMAT/LVST.

Evaluation of sequence alignments and oligonucleotide probes with respect to three-dimensional structure of ribosomal RNA using ARB software package.

Background: Availability of high-resolution RNA crystal structures for the 30S and 50S ribosomal subunits and the subsequent validation of comparative secondary structure models have prompted the biologists to use three-dimensional structure of ribosomal RNA (rRNA) for evaluating sequence alignments of rRNA genes. Furthermore, the secondary and tertiary structural features of rRNA are highly useful and successfully employed in designing rRNA targeted oligonucleotide probes intended for in situ hybridization experiments. RNA3D, a program to combine sequence alignment information with three-dimensional structure of rRNA was developed.

A particle system for interactive visualization of 3D flows.

We present a particle system for interactive visualization of steady 3D flow fields on uniform grids. For the amount of particles we target, particle integration needs to be accelerated and the transfer of these sets for rendering must be avoided. To fulfill these requirements, we exploit features of recent graphics accelerators to advect particles in the graphics processing unit (GPU), saving particle positions in graphics memory, and then sending these positions through the GPU again to obtain images in the frame buffer.