European association of echocardiography recommandations for standardization of performance, digital staorage and reporting of echocardiographic studies

peer reviewedIn view of the European Association of Echocardiography (EAE) mission statement “To promote excellence in clinical diagnosis, research, technical development, and education in cardiovascular ultrasound in Europe” and the increasing demand for standardization and quality control, the EAE have established recommendations and guidelines for standardization of echocardiography performance, data acquisition (images, measurements and morphologic descriptors), digital storage and reporting of echocardiographic studies. The aim of these recommendations is to provide a European consensus document on the minimum acceptable requirements for the clinical practice of echocardiography today and thus improve the quality and consistency of echocardiographic practice in Europe

Multi- Modal Characterization Of Left Ventricular Diastolic Filling Physiology

Multiple modalities are clinically used to quantify cardiovascular function. Most clinical indexes derived from these modalities are empirically derived or correlation- based rather than causality based. Hence these indexes don\u27t provide insight into cardiac physiology and the mechanism of dysfunction. Our group has previously developed and validated a mathematical model using a kinematic paradigm of suction- initiated ventricular filling to understand the mechanics of early transmitral flow and the associated physiology/ pathophysiology. The model characterizes the kinematics of early transmitral flow analogous to a damped simple harmonic oscillator with lumped parameters- ventricular stiffness, ventricular viscoelasticity/ relaxation and ventricular load. The current research develops the theme of causal mechanism based quantification of physiology and uses the kinematic model to study intraventricular fluid mechanics in diastole. In the first project, the role of vortex rings in efficient diastolic filling was investigated. Vortex rings had been previously characterized by a dimensionless index called vortex formation time (VFT). We re- expressed VFT in terms of ventricular kinematic properties- stiffness, viscoelasticity and volumetric preload, using the kinematic model. This VFTkinematic could be calculated using data from a clinical echocardiographic study. The VFTkinematic was a sensitive to physiologic changes as verified by its correlation with a clinically used echo- based index of filling pressure. Additionally, we demonstrated that VFTkinematic, by factoring the ventricular expansion rate, could differentiate between normal filling pattern and pseudonormal filling pattern which is characteristic of moderate DD. Continuing on our study of intraventricular fluid mechanics, we next studied the development of vortex ring in the ventricle. We discovered that as the vortex ring develops, the leading edge of the circulating flow passes through the main inflow tract. This causes an extra flow wave recorded in transmitral Doppler echocardiography (in addition to early and late filling waves) that had been observed previously. By using cardiac magnetic resonance (CMR) and echocardiography to independently measure intraventricular vortexes we were able to provide a causal explanation for the extra flow wave and its clinical consequences. We developed another approach to quantify the effect of chamber kinematics on filling via directional flow impedances. In the ventricle, both pressure and flow rate are oscillatory and pressure oscillations cause flow rate changes. Hence a frequency based approach via impedance, to quantify the relationship between pressure and flow rate is intuitive. We developed expressions for longitudinal and transverse flow impedances which could be computed from cardiac catheterization and echocardiographic data. Longitudinal and transverse flow impedances allowed us to quantify the previously observed directionality of filling as a function of harmonics and use it as an index to measure pathophysiologic changes. While fluid mechanics based indexes provide a method to evaluate LV chamber kinematics in diastole, an alternate approach for DF quantification is LV hemodynamic assessment. Since, LV filling is influenced by pressure changes before and during filling, we investigated the spatial pressure gradient in the LV. We measured the pressure difference between the LV apex and mid-LV using catheterization and we found a larger gradient exists during isovolumic relaxation (2- 3 times) as compared to filling. Additionally, the rate of pressure decay as quantified by different models of relaxation was also significantly different at the two locations. Additionally, we developed a new method for load independent hemodynamic analysis of the cardiac cycle. Load represents the pressure against which the ventricle has to fill and eject and most LV function indexes are load dependent, which can confound the diagnosis of dysfunction. We computed load independent cardiac cycle hemodynamics by normalizing LV pressure and the rate of change of pressure (dP/dt). Normalization revealed the presence of conserved kinematics during isovolumic relaxation particularly the normalized pressure at peak negative dP/dt while a similar feature was not observed during the contraction. These studies demonstrate the advantage of mechanism based approaches to quantify diastolic physiology

Speckle-Tracking Imaging, Principles and Clinical Applications: A Review for Clinical Cardiologists

Evaluation of myocardial mechanics, although complex, has now entered the clinical arena, thanks to the introduction of bedside imaging techniques, such as speckle-tracking echocardiography

Left Ventricular Fluid Mechanics: the long way from theoretical models to clinical applications

\u2014The flow inside the left ventricle is characterized by the formation of vortices that smoothly accompany blood from the mitral inlet to the aortic outlet. Computational fluid dynamics permitted to shed some light on the fundamental processes involved with vortex motion. More recently, patient-specific numerical simulations are becoming an increasingly feasible tool that can be integrated with the developing imaging technologies. The existing computational methods are reviewed in the perspective of their potential role as a novel aid for advanced clinical analysis. The current results obtained by simulation methods either alone or in combination with medical imaging are summarized. Open problems are highlighted and perspective clinical applications are discussed

Kinematic Characterization of Left Ventricular Chamber Stiffness and Relaxation

Heart failure is the most common cause of hospitalization today, and diastolic heart failure accounts for 40-50% of cases. Therefore, it is critical to identify diastolic dysfunction at a subclinical stage so that appropriate therapy can be administered before ventricular function is further, and perhaps irreversibly impaired. Basic concepts in physics such as kinematic modeling provide a unique method with which to characterize cardiovascular physiology, specifically diastolic function (DF). The advantage of an approach that is standard in physics, such as the kinematic modeling is its causal formulation that functions in contrast to correlative approaches traditionally utilized in the life sciences. Our research group has pioneered theoretical and experimental quantitative analysis of DF in humans, using both non-invasive (echocardiography, cardiac MRI) and invasive (simultaneous catheterization-echocardiography) methods. Our group developed and validated the Parametrized Diastolic Filling (PDF) formalism which is motivated by basic physiologic principles (LV is a mechanical suction pump at the mitral valve opening) that obey Newton\u27s Laws. PDF formalism is a kinematic model of filling employing an equation of motion, the solution of which accurately predicts all E-wave contours in accordance with the rules of damped harmonic oscillatory motion. The equation\u27s lumped parameters--ventricular stiffness, ventricular viscoelasticity/relaxation and ventricular load--are obtained by solving the `inverse problem\u27. The parameters\u27 physiologic significance and clinical utility have been repeatedly demonstrated in multiple clinical settings. In this work we apply our kinematic modeling approach to better understand how the heart works as it fills in order to advance the relationship between physiology and mathematical modeling. Through the use of this modeling, we thereby define and validate novel, causal indexes of diastolic function such as early rapid filling energy, diastatic stiffness, and relaxation and stiffness components of E-wave deceleration time

Hot Topics in Echocardiography

Echocardiography is still the most used imaging technique for the evaluation of cardiac anatomy and function and today it plays an essential role in daily decision making. The echocardiographic technology and its applications have widely developed in the last years leading to a better diagnostic accuracy. On the other hand echocardiography specialists have new clinical questions to answer. Echocardiography meets the growing need for non-invasive imaging in the expanding heart failure population and during structural heart interventions. The new percutaneous therapies need, a precise evaluation of cardiac dimensions and a complete understanding of the spatial relationships between cardiac structures. Echocardiography is of paramount importance both during the patient evaluation and guiding the procedure. This book tries to give an in depth evaluation about the specific issues that a modern cardiovascular imaging specialist is asked to answer nowadays

Echocardiography

The book "Echocardiography - New Techniques" brings worldwide contributions from highly acclaimed clinical and imaging science investigators, and representatives from academic medical centers. Each chapter is designed and written to be accessible to those with a basic knowledge of echocardiography. Additionally, the chapters are meant to be stimulating and educational to the experts and investigators in the field of echocardiography. This book is aimed primarily at cardiology fellows on their basic echocardiography rotation, fellows in general internal medicine, radiology and emergency medicine, and experts in the arena of echocardiography. Over the last few decades, the rate of technological advancements has developed dramatically, resulting in new techniques and improved echocardiographic imaging. The authors of this book focused on presenting the most advanced techniques useful in today's research and in daily clinical practice. These advanced techniques are utilized in the detection of different cardiac pathologies in patients, in contributing to their clinical decision, as well as follow-up and outcome predictions. In addition to the advanced techniques covered, this book expounds upon several special pathologies with respect to the functions of echocardiography