Journal ArticleDOI
Spatio-temporal mapping of intracardiac pressure gradients. A solution to Euler's equation from digital postprocessing of color Doppler M-mode echocardiograms.
TLDR
The method shows that intracardiac instantaneous pressure gradients can be analysed noninvasively using color Doppler M-mode echocardiography combined with image postprocessing methods.Abstract:
Doppler assessment of intracardiac pressure gradients using the simplified Bernoulli equation is inaccurate in the absence of a restricted orifice. The purpose of this study is to develop a new general method to map instantaneous pressure gradients inside the heart using Doppler echocardiography. Color Doppler M-mode recordings are digitally postprocessed with a software algorithm that decodes flow velocity and fits a bivariate spatio-temporal tensor-product smoothing spline. Temporal and spatial accelerations are then calculated by analytical derivation of the fitted velocity data, allowing solution of both inertial and convective terms of Euler's equation. A database of 39 transmitral inflow and transaortic outflow color Doppler M-mode recordings from 20 patients with a number of cardiac conditions was analysed, along with matched pulsed-wave spectral recordings. A close agreement was observed between the spectral and postprocessed color Doppler velocity values (error = 0.8 +/- 11.7 cm/s), validating the data decoding and fitting process. Spatio-temporal pressure-gradient maps were obtained from all studies, allowing visualisation of instantaneous pressure gradients from the atrium to the apex during left ventricular filling, and from the apex to the outflow tract during ejection. Instantaneous pressure differences between localised intracardiac sample points closely matched previously published catheterization findings, both in magnitude and waveform shape. Our method shows that intracardiac instantaneous pressure gradients can be analysed noninvasively using color Doppler M-mode echocardiography combined with image postprocessing methods.read more
Citations
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Journal ArticleDOI
Two-Dimensional Intraventricular Flow Mapping by Digital Processing Conventional Color-Doppler Echocardiography Images
Damien Garcia,J. C. del Alamo,David Tanne,Raquel Yotti,Cristina Cortina,Eric Bertrand,José Carlos Antoranz,Esther Pérez-David,Régis Rieu,Francisco Fernández-Avilés,Javier Bermejo +10 more
TL;DR: Clinical Doppler studies showed that the proposed echocardiographic method based on the continuity equation is fast, clinically-compliant and does not require complex training and will potentially enable investigators to study of additional quantitative aspects of intraventricular flow dynamics in the clinical setting by high-throughput processing conventional color-Doppler images.
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Support vector machines in engineering: an overview
TL;DR: The aim of this study is to review the current state of the SVM technique, and to show some of its latest successful results in real‐world problems present in different engineering fields.
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A Noninvasive Method for Assessing Impaired Diastolic Suction in Patients With Dilated Cardiomyopathy
Raquel Yotti,Javier Bermejo,J. Carlos Antoranz,Manuel Desco,Cristina Cortina,José Luis Rojo-Álvarez,Carmen Allue,Laura E. Martin,Mar Moreno,José A. Serrano,Roberto Muñoz,Miguel A. García-Fernández +11 more
TL;DR: Patients with dilated cardiomyopathy show an abnormally low diastolic suction and a blunted capacity to recruit suction with stress, which can be studied by using Doppler echocardiography.
Journal ArticleDOI
Contribution of the diastolic vortex ring to left ventricular filling.
Pablo Martinez-Legazpi,Javier Bermejo,Yolanda Benito,Raquel Yotti,Candelas Pérez del Villar,Ana González-Mansilla,Alicia Barrio,Eduardo Villacorta,Pedro L. Sánchez,Francisco Fernández-Avilés,Juan C. del Álamo +10 more
TL;DR: The diastolic vortex is responsible for entering a significant fraction of LV filling volume at no energetic or pressure cost, and intraventricular fluid mechanics are an important determinant of global chamber LV operative stiffness.
Journal ArticleDOI
Doppler-Derived Ejection Intraventricular Pressure Gradients Provide a Reliable Assessment of Left Ventricular Systolic Chamber Function
Raquel Yotti,Javier Bermejo,Manuel Desco,J. Carlos Antoranz,José Luis Rojo-Álvarez,Cristina Cortina,Carmen Allue,Hugo Rodríguez-Abella,Mar Moreno,Miguel A. García-Fernández +9 more
TL;DR: Doppler-derived EIVPDs provide quantitative, reproducible, and relatively load-independent indices of global systolic chamber function that correlate closely with currently available reference methods.
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