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Background: Optimal atrioventricular delay (AVD) achieves maximum cardiac output in patients undergoing cardiac resynchronization therapy (CRT). Nonoptimal AVD decreases left ventricular (LV) end-diastolic volume and causes loss of flow momentum prior to LV ejection., Objective: We investigated the potential role of energy dissipation (ED) in these changes in cardiac output through the study of intraventricular flow. We hypothesized that short and long AVD increases ED when compared with optimal AVD by altering the physiologic flow mechanics that preserve kinetic energy in the LV., Methods: Forty-four patients under CRT underwent echocardiographic LV flow analysis under optimal, short, and long AVD. LV ED and vortical flow in the inflow-outflow tract were studied during the end-diastolic and early systolic period, and paired comparisons were obtained between optimal and nonoptimal values., Results: ED in the left ventricle was minimal in optimal AVD and significantly increased with nonoptimal values (79.1 ± 27.5 J/m·sec in optimal AVD vs 96.5 ± 34.7 J/m·sec in short AVD; n = 18, P = .006; 123.3 ± 67.6 J/m·sec in optimal AVD vs 292.4 ± 202.5 J/m·sec in long AVD; P < .001). Increase in ED occurred due to inadequate flow redirection toward the outflow tract in short AVD and due to both turbulence and prolonged ineffective flow rotation in long AVD., Conclusions: Optimal AVD in resynchronization therapy favors physiological vortex flow patterns in the left ventricle during the end-diastolic and early systolic period. These patterns are altered when nonoptimal values are programmed, increasing ED., (Copyright © 2019 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Cardiac surgery induces geometrical and functional changes, which are not clearly explained. Objective: to investigate the physiopathology of the heart after cardiac surgery using advanced techniques of echocardiography. Thirty patients undergoing cardiac surgery had echocardiographic study prior and after surgery. Left and right ventricular (RV) longitudinal displacement and strain were studied with speckle-tracking. Using longitudinal displacement, we defined a static longitudinal reference-point (sLRP) to which the other segments moved during systole. Transversal displacement and global function were determined by conventional-echo. Left and RV segments showed systolic longitudinal displacement towards the apex, which was the sLRP before surgery; and towards the medium segment of lateral RV-wall one week after surgery. The displacement of basal RV segment towards this sLRP was smaller, causing decreased TAPSE. Apical segments showed an inverse displacement towards the new sLRP, and septum displacement was decreased or inverted towards the lateral RV-wall, causing paradoxus septal motion. RV-wall longitudinal strain was reduced (- 23.1 ± 8.6 vs. - 14.6 ± 5.3;p < 0.001), RV transversal fractional shortening was increased (36.5 ± 10.5 vs. 41.7 ± 13; p = 0.011), and the RV fractional area change was unchanged (46.7 ± 9.5 vs. 47.8 ± 11.7; p = 0.625). The medium segment of RV lateral wall, in contact with sternotomy, remains static after surgery and acts as a new sLRP towards which the rest of segments move, explaining the reduction of TAPSE and paradoxus septal motion. The longitudinal strain of the lateral RV-wall gets impaired, but an increase of transversal motion maintains global RV function.

Background: Swirling flow, organized in vortices, contributes to adequate left ventricular function. In this study, we apply a novel echocardiographic flow-mapping technique, vector flow mapping (VFM), to evaluate the main characteristics of left ventricular vortices and its relation to filling parameters., Methods: Forty-eight subjects underwent conventional transthoracic echocardiographic examination with additional intracardiac flow assessment with VFM using a Aloka Alpha-10 system and experimental VFM analysis software. To analyze vortex behavior, its rotation direction, duration, location inside the left ventricle, size, and intensity were assessed in apical long-axis view. Its relation to conventional left ventricular filling parameters was then analyzed., Results: Two vortex components were consistently identified following each transmitral filling wave. The anterior component of these visualized vortices was analyzed, due to its higher significance in the cardiac cycle, following early filling (V1) and atrial contraction (V2). Differences were observed in several aspects of vortex behavior between V1 and V2, particularly in patients with normal left ventricular filling parameters. These differences may be related to varying roles of vortices in different periods of the cardiac cycle., Conclusions: Vector flow mapping allowed visualization and measurement of several parameters defining vortex behavior inside the cardiac cycle. The differences observed in these parameters between vortices in different phases of the cardiac cycle may be related to their role in optimizing cardiac function., (© 2014, Wiley Periodicals, Inc.)

We describe the use of vector flow mapping (VFM), a novel echocardiographic technique allowing intracardiac flow visualization, to quantify flow intensity inside a left ventricular aneurysm in a 68-year-old man. VFM successfully identified areas of stagnant flow corresponding to the wall region where a thrombus had been formed., (© 2013, Wiley Periodicals, Inc.)

Introduction: Left atrial (LA) size is an indicator of the pressure to which it is chronically subjected. Although guidelines recommend measuring it using volume indexed to body surface, the anteroposterior diameter is still normally used., Aim: To evaluate which of these measurements correlates better with atrial pressure-related echocardiographic parameters., Methods: Atrial diameter and volume, together with parameters of systolic function, diastolic function, pressure, and degree of mitral regurgitation, were measured in 121 consecutive outpatients., Results: Atrial diameter correlated with its indexed volume (r: 0.69) with a low degree of agreement for detecting dilation (Kappa: 0.51). Atrial diameter was related to the parameters associated with atrial pressure: E/E' (r: 0.44), pulmonary vein systolic/diastolic rates quotient (r: 0.25) and degree of mitral regurgitation (r: 0.19). The correlations improved when volume indexed to body surface was measured (r: 0.52; 0.38 and 0.44, respectively). In a multiple regression analysis that included E/E', pulmonary vein flow and degree of mitral regurgitation, LA diameter depended entirely on E/E' (r: 0.44; B: 0.04; P: 0.000). The relationship improved when the diameter was corrected for body surface or the volume was measured (r: 0.54 and 0.54, respectively), and in particular when volume indexed to body surface was measured (r: 0.66). In this case, pulmonary vein flow (B: 6.8; P: 0.03), degree of mitral regurgitation (B: 5.2; P: 0.000) and E/E' ratio (B: 0.8; P : 0.000) were included in the equation., Conclusions: Indexed atrial volume correlates better with LA pressure surrogates than the anteroposterior diameter, even when this is corrected for body surface., (© 2010, Wiley Periodicals, Inc.)