Regional Disparities of Left Atrial Appendage Wall Contraction in Patients With Sinus Rhythm and Atrial Fibrillation

2019 ◽  
Vol 32 (6) ◽  
pp. 755-762 ◽  
Author(s):  
Gerardo E. Farese ◽  
Bhupendar Tayal ◽  
Stephan Stöbe ◽  
Ulrich Laufs ◽  
Andreas Hagendorff
2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
S Ijuin ◽  
A Hamadanchi ◽  
F Haertel ◽  
L Baez ◽  
C Schulze ◽  
...  

Abstract Background Percutaneous left atrial appendage closure (LAAC) is being established as an alternative option for atrial fibrillation (AF) patients with high bleeding risk. Few studies reported the influence of percutaneous LAAC on left atrial (LA) performance, but most of the studies demonstrated no remarkable changes in their parameters after the procedure. Method The study included 95 patients (age: 75±6.7 years, 67% male) whom underwent percutaneous LAAC in a single center between September 2012 and November 2018. LA strain was evaluated at three different time intervals by transesophageal echocardiography (baseline, 45 days and 180 days after procedure). All data were analyzed using a dedicated. 70 patients had atrial fibrillation whereas 25 were in sinus rhythm. Analysis was performed for peak atrial longitudinal strain (PALS) and peak atrial contraction strain (PACS) from segment of lateral wall in mid-esophageal 4 chamber view. The validity of lateral wall left atrial analysis was recently shown by our group. PACS was obtained in patients with sinus rhythm during exams. Results Compared to baseline, PALS was significantly increased after 45 days (12.4±8.4% vs 16.0±10.7%, p=0.001) and remained stable after 180 days (13.8±9.0% vs 17.0±12.4%, p=0.098). Even in only patients with atrial fibrillation during exams, it was increased (10.8±7.7% vs 13.4±7.1%, p=0.012 and 8.5±5.1% vs 13.9±8.1%, p=0.014). Similarly, compared with the baseline, PACS was significantly increased after 45 days and 180 days (5.8±3.9% vs 10.6±7.6%, p=0.001 and 4.5±2.6% vs 7.9±3.1%, p=0.036). The Changes in PALS and PACS Conclusion Our study has demonstrated for the first time the improvement in LA strain following LAAC within 45 days of implantation by transesophageal echocardiography and these values were maintained at least for 6 months. Further appraisal is warranted for confirmation of these preliminary findings.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Jonathan H Chung ◽  
Gordon Ho ◽  
Andrew Schluchter ◽  
Francisco Contijoch ◽  
Jonathan C Hsu ◽  
...  

Introduction: The formation of thrombus in the left atrial appendage (LAA) and risk for systemic embolization may result in part from stasis and poor blood volume emptying during atrial fibrillation (AF). Functional 4-dimensional computed tomography (4DCT) is a promising technique to measure LAA ejection fraction and blood volume emptying. Hypothesis: We hypothesize that the LAA ejection fraction measured by 4DCT is decreased during AF compared to sinus rhythm. Methods: 256-slice 4DCT scans obtained in patients for coronary artery imaging or pre-procedurally for AF, VT or SVT ablation procedures were analyzed retrospectively. In each patient, LAA volumes were measured at multiple phases during one cardiac cycle using segmentation software (ITK-SNAP and Osirix MD). LAA ejection fraction was calculated as the difference between minimum and maximum volumes and was analyzed using Wilcoxon rank sum. Results: Out of 54 patients, 37 patients were in sinus rhythm and 17 patients were in AF. Between NSR vs. AF, mean age was 69.1±12.8 vs 73.2±11.5 years (p=0.13), 28% vs 36% female (p=0.54), LVEF was 58±11% vs 60±9% (p=0.95), and echo-derived left atrial volume index was 29.5±6.1 ml/m2 vs 41.7±12.8 ml/m2 (p=0.06). Patients who were in sinus rhythm during their CT scan had a higher LAA ejection fraction than those who were in AF (58±13% vs. 29±9%, p<0.0001). For patients who were in AF during their CT scan, there was no difference in LAA ejection fraction between patients with a history of paroxysmal AF compared to patients with a history of persistent AF (30±10% vs. 28±10%, p=0.75). Conclusions: Analysis of the LAA volumes using functional cardiac CT is a feasible method to quantify blood volume emptying from the LAA. Patients in AF were observed to have significantly decreased LAA ejection fraction and blood volume emptying compared to patients in sinus rhythm. Further studies are needed to determine whether this technique may improve personalized risk stratification for stroke.


EP Europace ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 5-18 ◽  
Author(s):  
Nabeela Karim ◽  
Siew Yen Ho ◽  
Edward Nicol ◽  
Wei Li ◽  
Filip Zemrak ◽  
...  

Abstract For many years, the left atrial appendage (LAA) was considered a dormant embryological remnant; however, it is a structurally complex and functional organ that contributes to cardiac haemodynamic changes and volume homeostasis through both its contractile properties and neurohormonal peptide secretion. When dysfunctional, the LAA contributes to thrombogenesis and subsequent increased predisposition to cardioembolic events. Consequently, the LAA has gained much attention as a therapeutic target to lower this risk. In addition, attention has focused on the LAA in its role as an electrical trigger for atrial tachycardia and atrial fibrillation with ablation of the LAA to achieve electrical isolation showing promising results in the maintenance of sinus rhythm. This in-depth review explores the structure, physiology and pathophysiology of the LAA, as well as LAA intervention and their sequelae.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mei-Yao Wu ◽  
Yen-Nien Lin ◽  
Hung-Pin Wu ◽  
Ying-Ying Huang ◽  
Jan-Yow Chen ◽  
...  

AbstractImpaired left atrial appendage ejection fraction (LAA-EF) and peak LAA flow velocity (LAA-FV) are associated with high thromboembolic risks in patients with atrial fibrillation (AF). Herein, we examined LAA function among patients with atrial flutter (AFL) stratified by the CHA2DS2-VASc score using transesophageal echocardiography (TEE). Of 231 consecutive patients with typical AFL, 84 who fulfilled the inclusion criteria were enrolled. Among them, 57 had ongoing AFL and were divided into the isolated AFL (n = 38) and AFL with paroxysmal AF (PAF) (n = 19) groups, depending on whether they had sporadic AF before TEE. The remaining 27 patients with spontaneous sinus rhythm during TEE were designated as controls. Both the LAA-FV (31.9 cm/s vs. 51.5 cm/s, P = 0.004) and LAA-EF (28.4% vs. 36.5%, P = 0.024) measured during AFL were significantly lower in the AFL + PAF group than in the isolated AFL group. Significant inverse correlations between the CHA2DS2-VASc score and LAA-EF were identified in the AFL (P = 0.008) and AFL + PAF (P = 0.032) groups. We observed progressive LAA dysfunction in patients with AFL + PAF compared with that in patients with isolated AFL, and the LAA-EF was inversely correlated with the CHA2DS2-VASc score in these patients. Our findings may have implications on the application of thromboprophylactic therapy in patients with AFL.


Cardiology ◽  
2016 ◽  
Vol 134 (4) ◽  
pp. 394-397
Author(s):  
Sajid Ali ◽  
Justin Ugwu ◽  
Yousuf Kanjwal

Background: Left atrial appendage thrombus formation is a known major complication of atrial fibrillation and atrial flutter which increases the risk of embolism and stroke. This risk of thrombosis is greatly increased with a lack of anticoagulation. After conversion to a normal sinus rhythm in these arrhythmias, the risk of thrombus formation in the left atrium persists through a phenomenon termed atrial myocardial stunning. Case: We present the case of a patient who previously underwent successful pulmonary vein isolation and was found to be in typical isthmus-dependent atrial flutter with a questionable recurrence of atrial fibrillation. The decision was made to return for atrial flutter ablation and for evaluation of prior pulmonary vein isolation. Initially, a transesophageal echocardiogram showed a normal ejection fraction, biatrial enlargement and no left atrial appendage thrombus. Ablation of the cavotricuspid isthmus was successfully accomplished with documented bidirectional block. A transesophageal echocardiogram probe was still in place prior to planned transseptal puncture for the evaluation of pulmonary veins. A large thrombus was now observed filling the left atrial appendage. Conclusion and Objective: Atrial stunning is a transient atrial contractile dysfunction that occurs whether sinus rhythm is restored spontaneously, electrically, pharmacologically or by ablation. We know after conversion that there is higher propensity to increased spontaneous echogenic contrast and decreased velocities; however, we do not have documented knowledge of exactly how soon after the conversion to a sinus rhythm a thrombus may be seen. We demonstrate a case of acute left atrial appendage thrombus formation immediately following the successful ablation of isthmus-dependent atrial flutter. Our report validates the belief that strategies of not interrupting anticoagulation prior to the conversion of these arrhythmias should be implemented.


2018 ◽  
Vol 21 (1) ◽  
pp. 044 ◽  
Author(s):  
Yongqing Chen ◽  
Fangju Su ◽  
Juanping Han ◽  
Piqi Jiao ◽  
Wenyun Guo

Aim: To study the expression of Rho kinase (Rho associated coil forming protein kinase-1, ROCK-1) and its substrate myosin phosphatase target subunit 1 (myosin phosphatase target subunit-1, MYPT-1), connexin 40 (Cx40) and connexin 43 (Cx43) in the left atrial appendage of patients with atrial fibrillation, and explore the role of ROCK signaling pathway in patients with atrial fibrillation and its underlying mechanism. Methods: 40 patients undergoing open heart surgery were divided into two groups; atrial fibrillation group (AF group) and sinus rhythm group (SR group). About 100 mg of left atrial appendage tissue was taken during surgery and quickly frozen in liquid nitrogen. Immunohistochemistry and western blot were performed to evaluate the expression and location of ROCK-1, MYPT-1, Cx40 and Cx43 in the left atrial appendage tissue. Results: The results indicated that the expression of ROCK-1, MYPT-1, and Cx40 in the left atrial appendage in patients with atrial fibrillation was significantly upregulated (P < .01), the difference in the two groups was statistically significant, and ROCK-1, Cx40, and MYPT-1 expression in the AF group were higher than those in sinus rhythm group; there was a weakly positive expression of Cx43 protein in the AF group and sinus rhythm group, the difference was not statistically significant, and ROCK-1 and MYPT-1 expression showed a significant positive correlation (r = 0.968, P < .05), MYPT 1 and Cx40 protein expression was also positively correlated (r = 0.983, P < .05). Evidence in the left atrial appendage tissue of patients with atrial fibrillation showed that some proteins in Rho/ROCK pathway were upregulated, and MYPT-1 and Cx40 protein expression in AF group were significantly higher than that of SR group, which was also positively correlated; Cx43 showed a weak positive expression in both the SR group and AF group, which indicates that Rho kinase may induce expression of Cx40 by phosphorylation of MYPT-1; Cx43 may not be involved, suggesting that Rho kinase signaling pathway may activate and play an important role in the pathogenesis of atrial fibrillation lesions.


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