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Aortic valve disease in the elderly
Published in Wilbert S. Aronow, Jerome L. Fleg, Michael W. Rich, Tresch and Aronow’s Cardiovascular Disease in the Elderly, 2019
Madhur A. Roberts, Ryan K. Kaple, Wilbert S. Aronow
Doppler echocardiography is used to measure peak and mean transvalvular gradients across the aortic valve and assess the severity of the valve lesion. Aortic valve area can be calculated by the continuity equation using pulsed Doppler echocardiography to measure LV outflow tract velocity, continuous-wave Doppler echocardiography to measure transvalvular flow velocity, and two-dimensional long-axis view to measure LV outflow tract area (59,60). Aortic valve area can be detected reliably by the continuity equation in elderly patients with AS (58). Figures 16.1 through 16.5 illustrate two-dimensional echocardiographic findings (Figures 16.1 and 16.3), continuous-wave Doppler echocardiographic findings (Figures 16.2 and 16.4), and simultaneous LV and femoral arterial pressure tracings (Figure 16.5) in elderly patients with severe valvular AS.
Echocardiogram
Published in Neeraj Parakh, Ravi S. Math, Vivek Chaturvedi, Mitral Stenosis, 2018
Pressure half-time (PHT) is obtained on the mitral inflow doppler trace and is defined as the time in milliseconds for the transmitral gradient to decrease by half of its original value in early diastole (Figure 8.15a). The concept was originally developed during cardiac catheterization studies20 and subsequently adopted for doppler echocardiography by Hatle and colleagues,21 who described it as doppler time for the peak velocity to decrease by a factor of the square root of two. They then found an inverse relationship of this pressure half-time with MVA by the Gorlin equation and subsequently provided the equation for empirical calculation of MVA from PHT.22 MVA (cm2) = 220/T1/2 (ms), where T1/2 is the PHT on the deceleration slope of the E wave.
Percutaneous transvenous mitral commissurotomy
Published in Ever D. Grech, Practical Interventional Cardiology, 2017
Notice: Despite the above explanation, Doppler echocardiography is not always necessary, especially for young patients with favourable valve morphology as frequently encountered in developing countries. Usually, commissure adhesions in such patients are not so tough and can be separated adequately without severe regurgitation. Therefore, it is feasible to assess the degrees of both mitral stenosis and resultant regurgitation by using simpler conventional methods such as pressure measurement, left atrial pressure patterns (increase in V wave), auscultation and left ventricular angiography.
The Association between Hemodynamically Significant Patent Ductus Arteriosus and 25-Hydroxyvitamin D Levels in Preterm Infants ≤32 Weeks Gestational Age
Published in Fetal and Pediatric Pathology, 2023
Recent studies have shown that the ductus arteriosus, which is required during fetal life, functionally closes in term infants in the first 72 hours after birth [1–3]. Failure of this shunt’s closing within the expected time is defined as patent ductus arteriosus (PDA). The frequency of PDA in term infants is approximately 6 per 10,000 live births [4]. The frequency of PDA increases inversely with the gestational age (GA) and birth weight (BW) [5]. Respiratory distress, sepsis, higher fluid intake, absence of antenatal corticosteroids, phototherapy and use of furosemide are other important risk factors [1,6]. Systemic hypotension, continuous or systemic murmur, oliguria, prolonged mechanical ventilation (MV) time, decreased oxygen (O2) saturation and feeding intolerance are some clinical findings of PDA [6]. PDA increases the risk of bronchopulmonary dysplasia and necrotizing enterocolitis [7]. A chest radiograph shows cardiomegaly and increased opacities [8]. Metabolic acidosis and an increase in B-type natriuretic peptide are laboratory findings [6]. Doppler echocardiography is used to confirm the diagnosis of PDA [3].
Prevalence and diagnostic value of extra-left ventricle echocardiographic findings in transthyretin-related cardiac amyloidosis
Published in Amyloid, 2022
Gianluca Di Bella, Francesco Cappelli, Roberto Licordari, Paolo Piaggi, Mariapaola Campisi, Diego Bellavia, Fabio Minutoli, Luca Gentile, Massimo Russo, Cesare de Gregorio, Federico Perfetto, Anna Mazzeo, Calogero Falletta, Francesco Clemenza, Giuseppe Vita, Scipione Carerj, Giovanni Donato Aquaro
Transthoracic colour Doppler echocardiography (ECHO) was performed using commercial ultrasound machines (Vivid 7 or Vivid 9, GE Ultrasound, Horten, Norway) equipped with a phased-array adult cardiology transducer. Parasternal short-axis views at the basal, mid and apical LV levels, short-axis view of the aortic valve and standard apical views (four-chamber, two-chamber, five-chamber and LV outflow long-axis) were acquired. The measurement of left ventricular septal thickness in tele-diastole was made avowing structures like moderator band, false tendon and trabecular structure of both ventricles. All conventional measurements were acquired according to the recommendations of the American Society of Echocardiography and the European Association of Cardiovascular Imaging [18–19].
Artificial intelligence: improving the efficiency of cardiovascular imaging
Published in Expert Review of Medical Devices, 2020
Andrew Lin, Márton Kolossváry, Ivana Išgum, Pál Maurovich-Horvat, Piotr J Slomka, Damini Dey
AI has been increasingly applied to the automated quantification of 2D and 3D echocardiograms. Early software used traditional ML to automatically perform rapid and accurate calculation of LV ejection fraction based on 2D LV volumes [47]. ML and DL algorithms have since been utilized to quantify a variety of other 2D parameters such as LV hypertrophy [48], wall motion abnormalities [49], myocardial velocity [50], and longitudinal strain [51]. Doppler echocardiography, which measures blood flow, provides a velocity-time image for assessment of valvular function. A ML framework using hierarchical clustering has provided automated Doppler measurements of mitral inflow and aortic and tricuspid regurgitation [52]. Further, a support vector machine was able to accurately quantify the severity of mitral regurgitation based on textural features on 2D images [53].