Preoperative Left Atrial Mechanical Dysfunction Predicts Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft Operation - A Velocity Vector Imaging-Based Study -

Abstract

Background:The aim of the present study was to evaluate pre-existent subclinical mechanical atrial dysfunction in patients with postoperative atrial fibrillation (POAF) by using novel echocardiographic techniques. Methods and Results:Ninety-six patients with sinus rhythm, undergoing coronary artery bypass graft (CABG) operation were prospectively enrolled. Preoperative left atrial (LA) reservoir, conduit and booster functions were evaluated by 3 different methods: conventional echocardiography, tissue Doppler imaging (TDI), and 2-dimensional strain imaging based-velocity vector imaging (VVI). POAF occurred in 25 out of 96 patients (26%). LA volume index (LAVI) was the only conventional parameter associated with POAF. TDI-derived LA velocities were similar in study groups. In VVI analysis, LA systolic strain, strain rate (SRs) and early diastolic strain rate (ESRd) were impaired in patients who developed POAF after CABG (P=0.0001). Age, LAVI, LA peak systolic strain, SRs and ESRd were found to be the independent predictors of POAF. The optimal cut-off point of 44.0% (88.7% sensitivity, 96% specificity) for LA strain, 1.7 s -1 (88% sensitivity, 86.2% specificity) for SRs and 1.95 s -1 (sensitivity 72%, 70.4% specificity) for ESRd predicted POAF in this study.Conclusions: VVI-derived strain imaging could be used as an adjunctive non-invasive method for evaluating subclinical atrial mechanical dysfunction in patients undergoing CABG. This might help us to identify patients with high risk of POAF in clinical practice. (Circ J 2010; 74: 2109 - 2117

Left Atrial Longitudinal Strain Parameters Predict Postoperative Persistent Atrial Fibrillation Following Mitral Valve Surgery: A Speckle Tracking Echocardiography Study

“…Benedetto et al in their study of patients undergoing CABG, proved that peak atrial systolic mitral annular tissue Doppler velocity <9 cm/sec could predict AF. 43 44 Previous studies have recently demonstrated that global PALS, which reflects the passive stretching of the left atrium during LV systole, is an accurate measurement of LA reservoir function. Speckle tracking echocardiography, by which tissue markers (speckles) are tracked from frame to frame throughout the cardiac cycle, has been recently used for evaluation of myocardial deformation.…”

“…Teyyaraci et al in their study of patients undergoing CABG, VVI-based LA strain, systolic strain rates and early diastolic strain rate were independent predictor of POAF. 43 Again, Gabriella et al studied patients undergoing CABG demonstrated that STE-based LA strain and strain rate were lower in patients who developed POAF. 17 Cameli et al followed 197 patients with mitral regurgitation, and found that those who developed paroxysmal AF had lower global atrial longitudinal strain (16.3 AE 2.9 vs. 33.9 AE 4.4; P < 0.05).…”

Characteristics of Intra-Left Atrial Flow Dynamics and Factors Affecting Formation of the Vortex Flow

“…[25][26][27] However, this technique is available only in the 2D mode of TTE, is difficult to use in the evaluation of vortex, and is limited in terms of sub-optical images in patients with obesity or emphysema. 4D-Flow can clearly and non-invasively measure all 3D components of the vectors of blood velocity relative to all 4 spatio-temporal dimensions of the heart and great vessels, which has otherwise been difficult in TTE.…”

Relationship of CHA2DS2-VASc and CHADS2 Score to Left Atrial Remodeling Detected by Velocity Vector Imaging in Patients with Atrial Fibrillation

“…Traditional approaches assessing atrial remodeling is conventional echocardiography in clinical practice [8,23]. A widely used parameter of assessing LA remodeling by echocardiography is LA Anterior-Posterior diameter in the parasternal long-axis view [7].…”

“…Because of the combination of speckle tracking (a series of unique B-mode pixel tracking algorithms), mitral annulus motion and tissue-blood border detection, VVI show more feasible and reproducible in assessing LA remodeling status of very thin atrial wall, compared with other echocardiographic methods [7], recently been applied to the evaluation left atrial mechanical dysfunction in coronary artery disease patients [8], regional myocardial dysfunction in patients with acute myocardial infarction [27], have emerged as a quantitative technique for the estimation of myocardial structure and function. Especially, LA strain derived from the VVI is inversely related to LA wall fibrosis, a key hallmark of LA remodeling.…”