Detection of left ventricular dysfunction by global longitudinal systolic strain in patients with chronic aortic regurgitation.

Background: The purpose of this study was to investigate whether global longitudinal strain measured by two-dimensional speckle tracking echocardiography could detect incipient myocardial dysfunction in patients with chronic aortic regurgitation (AR). Disclosing left ventricular (LV) dysfunction is of decisive importance for optimal timing of surgery but challenging because of the altered loading conditions.

Methods: Forty-seven patients referred for aortic valve replacement because of chronic AR were studied, along with 31 healthy controls.

Noninvasive separation of large, medium, and small myocardial infarcts in survivors of reperfused ST-elevation myocardial infarction: a comprehensive tissue Doppler and speckle-tracking echocardiography study.

Background: The objective of the study was to evaluate the ability of established and new parameters of global systolic left ventricle function to estimate myocardial infarct size. Increasing infarct extent is associated with impaired prognosis in chronic ischemic heart disease. Systolic myocardial deformation is a complex 3D process that is mainly influenced by the amount and transmural distribution of viable myocardium.

Detecting myocardial ischaemia using miniature ultrasonic transducers--a feasibility study in a porcine model.

Background: Detection of myocardial ischaemia during and after cardiac surgery remains a challenge. Echocardiography is more sensitive in ischaemia detection than echocardiography (ECG) and haemodynamic monitoring, but demands repeated examinations for monitoring over time. We have developed and validated an ultrasonic system that permits continuous real-time assessment of myocardial ischaemia using miniature epicardial ultrasound transducers.

Clinical assessment of left ventricular rotation and strain: a novel approach for quantification of function in infarcted myocardium and its border zones.

Left ventricular (LV) circumferential strain and rotation have been introduced as clinical markers of myocardial function. This study investigates how regional LV apical rotation and strain can be used in combination to assess function in the infarcted ventricle. In healthy subjects (n = 15) and patients with myocardial infarction (n = 23), LV apical segmental rotation and strain were measured from apical short-axis recordings by speckle tracking echocardiography (STE) and MRI tagging.

Diagnostic capability and reproducibility of strain by Doppler and by speckle tracking in patients with acute myocardial infarction.

Objectives: The objective of the present study was to investigate the ability of strain by Doppler and by speckle tracking echocardiography in the acute phase in patients with ST-segment elevation myocardial infarction (STEMI) to diagnose left ventricular (LV) infarct size. Furthermore, we wanted to study at which time during the cardiac cycle strain should be measured.

Background: The assessment of regional myocardial dysfunction may be an important diagnostic tool in the evaluation of acute myocardial injury.

Feasibility of a three-axis epicardial accelerometer in detecting myocardial ischemia in cardiac surgical patients.

Objective: We investigated the feasibility of continuous detection of myocardial ischemia during cardiac surgery with a 3-axis accelerometer.

Methods: Ten patients with significant left anterior descending coronary artery stenosis underwent off-pump coronary artery bypass grafting. A 3-axis accelerometer (11 x 14 x 5 mm) was sutured onto the left anterior descending coronary artery-perfused region of left ventricle.

Mechanisms of preejection and postejection velocity spikes in left ventricular myocardium: interaction between wall deformation and valve events.

Background: Normal left ventricular myocardium demonstrates distinct spikes in the velocity trace before and after left ventricular ejection. We tested the hypothesis that the preejection and postejection velocity spikes reflect early systolic shortening and late systolic lengthening that are interrupted by mitral and aortic valve closure, respectively.

Methods And Results: In 11 anesthetized dogs, timing of valve closure was determined by pressure variables; left ventricular dimensions were determined by sonomicrometry.

Global longitudinal strain measured by two-dimensional speckle tracking echocardiography is closely related to myocardial infarct size in chronic ischaemic heart disease.

2D-STE (two-dimensional speckle tracking echocardiography) is a novel echocardiographic modality that enables angle-independent assessment of myocardial deformation indices. In the present study, we tested whether peak systolic epsilon(parallel) (longitudinal strain) values measured by 2D-STE could identify areas of MI (myocardial infarction) as determined by CE MRI (contrast-enhanced magnetic resonance imaging). Conventional echocardiographic apical long-axis recordings were performed in 38 patients, 9 months after a first MI.

Early prediction of infarct size by strain Doppler echocardiography after coronary reperfusion.

Objectives: The objective of this study was to investigate whether strain Doppler echocardiography performed immediately after revascularization by percutaneous coronary intervention could predict the extent of myocardial scar, determined by contrast-enhanced magnetic resonance imaging (MRI).

Background: There is considerable variability in survival rate after percutaneous coronary intervention, and accurate early risk stratification is therefore of major clinical importance.

Methods: Thirty individuals with acute anterior myocardial infarction were examined with longitudinal strain by Doppler 1.

Communication of medical images, text, and messages in inter-enterprise systems: a case study in Norway.

There is an increasing demand to discuss diagnostic images and reports of difficult cases with experienced staff. A possible solution besides physically transporting patients and material is to use high-speed communication networks to transfer images and reports electronically. With the web application PACSflow we have developed a solution to transfer images, reports, and messages as a single package in a one-step procedure.

Clinical and echocardiographic assessment of the Medtronic Advantage aortic valve prosthesis: the Scandinavian multicentre, prospective study.

Objective: The aim of this report is the prospective, multicentre evaluation of clinical results and haemodynamic performance of the Medtronic Advantage aortic valve prosthesis.

Methods: From April 2001 to June 2003, 166 patients (male:female 125:41; mean (SD) age 61.8 (11.

Mechanisms behind the postprandial increase in cardiac output: a clue obtained from transplanted hearts.

Consumption of a meal is followed by an increase in cardiac output (CO) which appears to be closely related to the concomitant increase in blood flow to the gastrointestinal organs. To gain information on the mechanism behind this increase in CO we have previously used Doppler ultrasound technique to record circulatory responses to a standardized meal in five patients with recently transplanted and thus denervated hearts. We obtained the surprising result that they reacted to the consumption of a meal with a greater increase in CO than did five matched normal controls.

Grading of myocardial dysfunction by tissue Doppler echocardiography: a comparison between velocity, displacement, and strain imaging in acute ischemia.

Objectives: The aim of the study was to compare the ability of the tissue Doppler echocardiographic imaging (TDI) modalities velocity, strain, and displacement to quantify systolic myocardial function.

Background: Several TDI modalities may be used to quantify regional myocardial function, but it is not clear how the different modalities should be applied.

Methods: In 10 anesthetized dogs we measured left ventricular pressure, longitudinal myocardial velocity, strain, and displacement by TDI at baseline and during left anterior descending coronary artery (LAD) stenosis and occlusion.

Reduced left ventricular function in hypoxemic newborn pigs: a strain Doppler echocardiographic study.

Myocardial dysfunction, hypotension, and increased pulmonary artery pressure are induced by asphyxia in neonates. We sought to define left ventricular (LV) systolic function by measuring longitudinal and radial contraction by strain Doppler echocardiography (SDE) in hypoxemic newborn pigs. Hypoxemia was induced in 11 anesthetized and instrumented newborn pigs by ventilation with 8% O2 in nitrogen.

Noninvasive myocardial strain measurement by speckle tracking echocardiography: validation against sonomicrometry and tagged magnetic resonance imaging.

Objectives: The aim of this study was to validate speckle tracking echocardiography (STE) as a method for angle-independent measurement of regional myocardial strain, using sonomicrometry and magnetic resonance imaging (MRI) tagging as reference methods.

Background: Tissue Doppler imaging allows non-invasive measurement of myocardial strain in the left ventricle (LV), but is limited by angle dependency.

Methods: Strain measurements with STE were obtained by a custom-made program that allowed tracking of two-dimensional motion of speckle patterns in a B-mode image.

Myocardial strain analysis in acute coronary occlusion: a tool to assess myocardial viability and reperfusion.

Background: This study proposes 2 new echocardiographic indices with potential application in acute coronary artery occlusion to differentiate between viable and necrotic myocardium and to identify reperfusion. We investigated whether the ratio between systolic lengthening and combined late and postsystolic shortening (L-S ratio) could identify viable myocardium and whether systolic myocardial compliance, calculated as systolic lengthening divided by systolic pressure rise, could identify necrotic myocardium.

Methods And Results: In anesthetized dogs, we measured left ventricular (LV) pressure and long-axis strain by Doppler echocardiography (SDE) and sonomicrometry.

New noninvasive method for assessment of left ventricular rotation: speckle tracking echocardiography.

Background: Left ventricular (LV) torsion is due to oppositely directed apical and basal rotation and has been proposed as a sensitive marker of LV function. In the present study, we introduce and validate speckle tracking echocardiography (STE) as a method for assessment of LV rotation and torsion.

Methods And Results: Apical and basal rotation by STE was measured from short-axis images by automatic frame-to-frame tracking of gray-scale speckle patterns.

Interaction between left ventricular wall motion and intraventricular flow propagation in acute and chronic ischemia.

Myocardial ischemia has been associated with left ventricular (LV) postsystolic shortening. The combination of tissue Doppler imaging and high frame-rate acquisition of two-dimensional color flow makes it possible to study the interaction between LV wall motion and intraventricular flow propagation. The aim of this study was to examine in a clinical model the impact that acute myocardial ischemia and prior myocardial infarct might have on LV flow patterns and to explain the underlying mechanisms from the tissue Doppler data.

Regional myocardial work by strain Doppler echocardiography and LV pressure: a new method for quantifying myocardial function.

There is a need for better methods to quantify regional myocardial function. In the present study, we investigated the feasibility of quantifying regional function in terms of a segmental myocardial work index as derived from strain Doppler echocardiography (SDE) and invasive pressure. In 10 anesthetized dogs, we measured left ventricular (LV) pressure by micromanometer and myocardial longitudinal strains by SDE and sonomicrometry.

Detection of ischemia and new insight into left ventricular physiology by strain Doppler and tissue velocity imaging: assessment during coronary bypass operation of the beating heart.

Background And Objectives: Detection of myocardial ischemia in humans by strain Doppler and tissue velocity imaging was validated in a novel, experimentally designed study model during coronary bypass operation of the beating heart.

Methods: Assessment of ischemia was made with an opened chest and pericardium inherent in the operative procedure. Longitudinal strain and tissue velocity of interventricular septal regions were measured by transesophageal echocardiography during occlusion of the left anterior descending coronary artery (LAD).

Tissue Doppler imaging for the diagnosis of coronary artery disease.

Purpose Of Review: Tissue Doppler imaging (TDI) is a diagnostic method that provides quantitative data about myocardial function. The present review discusses the most recent developments in the application of TDI in coronary artery disease.

Recent Findings: The most widely used TDI modality is velocity imaging, and systolic function is measured as peak velocity during LV ejection.

[Transcatheter closure of atrial septal defects in the oval fossa].

Background: We report five years' experience with transcatheter closure of defects in the oval fossa at Rikshospitalet University Hospital in Oslo, Norway.

Material And Methods: We reviewed the results in 69 patients between 1.3 and 74 years of age (median 5.

N-terminal proatrial natriuretic peptide in primary care: relation to echocardiographic indices of cardiac function in mild to moderate cardiac disease.

Aims: In patients with chronic heart failure plasma levels of N-terminal proatrial natriuretic peptide (Nt-proANP) correlate to cardiac filling pressures. The aim of the present study was to examine the relation between Nt-proANP plasma levels and echocardiographic indices of cardiac dysfunction in patients recruited from primary care.

Methods And Results: After clinical examination by the primary care physician, the patients were referred to one of two centres for echocardiography and blood sampling.

Postsystolic shortening in ischemic myocardium: active contraction or passive recoil?

Background: Postsystolic shortening in ischemic myocardium has been proposed as a marker of tissue viability. Our objectives were to determine if postsystolic shortening represents active fiber shortening or passive recoil and if postsystolic shortening may be quantified by strain Doppler echocardiography (SDE).

Methods And Results: In 15 anesthetized dogs, we measured left ventricular (LV) pressure, myocardial long-axis strains by SDE, and segment lengths by sonomicrometry before and during LAD stenosis and occlusion.