Atrial fibrillation ablation in patients with known sludge in the left atrial appendage

Purpose

Transesophageal echocardiography (TEE) is routinely used to assess for thrombus in the left atrium (LA) and left atrial appendage (LAA) in patients undergoing atrial fibrillation (AF) ablation. However, little is known about the outcome of AF ablation in patients with documented LAA sludge. We hypothesize that AF ablation can be performed safely in a proportion of patients with sludge in the LAA and may have a significant benefit for these patients.

Methods

We performed a retrospective analysis of all patients undergoing AF ablation at New York University Langone Medical Center (NYULMC) from January 1st 2011 to June 30, 2013. Patients with sludge found on their TEE immediately prior to AF ablation were identified and followed for stroke, AF recurrence, procedural complications, major bleeding, or death.

Results

Among 1,076 patients who underwent AF ablation, 8 patients (mean age 69?±?13 years; 75 % men) with sludge were identified. Patients with sludge in their LAA had no incidence of early or late occurrence of stroke during mean follow-up of 10 months. One patient had a left groin hematoma, and two patients had atrial tachycardias that needed a repeat ablation. TEE at the time of repeat ablation demonstrated the presence of spontaneous echo contrast (smoke) and resolution of sludge. There were no deaths.

Conclusion

In a cohort of eight patients with LAA sludge who underwent AF ablation, no significant thromboembolic events occurred during or after the procedure. AF ablation can be performed safely and may be beneficial in these patients. Larger studies are warranted to better determine the most appropriate management route.     

Anatomical analysis of the left atrial appendage using segmented, three-dimensional cardiac CT: a comparison of patients with paroxysmal and persistent forms of atrial fibrillation

Purpose

Successful implantation of percutaneous left atrial appendage (LAA) occlusion devices requires an accurate understanding of LAA anatomy and orifice dimensions. We sought to quantitatively compare LAA anatomy in patients with paroxysmal and persistent patterns of atrial fibrillation (AF).

Methods

Fifty-nine consecutive patients undergoing catheter ablation for AF underwent pre-procedural multislice cardiac computed tomography (CT) scans. Maximal LAA orifice dimensions and left atrial and LAA volumes were measured from three-dimensional segmented CT reconstructions. Thirty-six patients with paroxysmal and 23 with persistent AF were analysed.

Results

The mean maximal LAA orifice dimension was larger in persistent (27.2?±?4?mm) than paroxysmal AF (22.9?±?3?mm, p?r?=?0.76), maximal LAA orifice dimension (r?=?0.63) and left atrial volume.

Conclusions

Increased LAA orifice dimension is associated with left atrial enlargement in AF. This finding may impact LAA occlusion device sizing.     

Use of intracardiac echocardiography to guide implantation of a left atrial appendage occlusion device (PLAATO).

BACKGROUND: Over 90% of thrombi in atrial fibrillation (AF) originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA occlusion using the Percutaneous Left Atrial Appendage Transcatheter Occlusion system (PLAATO, ev3 Inc., Plymouth, MN). Transesophageal echocardiography (TEE) is typically used to guide implantation. OBJECTIVE: This study sought to examine the utility of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to TEE during PLAATO implantation. METHODS: The study group consisted of 10 patients who underwent PLAATO implantation with simultaneous TEE and ICE imaging guidance. ICE was used to perform the following tasks typically fulfilled by TEE: (1) verification of the absence of LAA thrombus, (2) identification of the LAA ostial dimension for device sizing, (3) guidance of transseptal puncture, (4) verification of the delivery sheath position, and (5) confirmation of location and stability of device before its irrecoverable release. The ability of ICE to perform these tasks was assessed from three separate positions: the standard right atrial (RA) position, within the coronary sinus (CS), and the right ventricular outflow tract. RESULTS: ICE imaging of the LAA was optimal from within the CS, although imaging from the proximal pulmonary artery provided better visualization of the distal LAA in cross-section. The LAA dimensions, confirmation of the absence of LAA thrombus, proper positioning of the delivery sheath, verification of location and stability of the device obtained by ICE were consistent with findings from TEE. CONCLUSION: Using nonconventional imaging planes, ICE imaging was able to perform the intraprocedural functions provided by TEE during implantation of the PLAATO left atrial appendage occlusion device.     

Left atrial thrombus despite continuous direct oral anticoagulant or warfarin therapy in patients with atrial fibrillation: insights into rates and timing of thrombus resolution

Purpose

Left atrial thrombus (LAT) may be detected by transesophageal echocardiography (TEE) in patients with atrial fibrillation (AF) or flutter (AFL) despite continuous anticoagulation therapy. We sought to examine the rates and timing of LAT resolution in response to changes in anticoagulation regimen.

Methods

A retrospective study of 1517 consecutive patients on ≥?4 weeks continuous oral anticoagulation (OAC) undergoing TEE prior to either direct current cardioversion or catheter ablation for AF or AFL was performed. Patients who had LAT on index TEE imaging and had follow-up TEEs were analyzed.

Results

Despite ≥?4 weeks of continuous anticoagulation therapy, 63 (4.2%) patients had LAT. Forty-four patients (median age 67 [IQR 58, 74]; 33 [75%] male; 25 [57%] on direct oral anticoagulant [DOAC]) had follow-up TEEs performed. Upon detection of LAT on index TEE, 8 patients switched from warfarin to a DOAC, 21 patients switched from a DOAC to warfarin or another DOAC, and 15 patients remained on the same OAC. Over median 4.2 months (IQR 2.9, 6.6), LAT resolution was seen in 25 (57%) patients. Of the 25 patients who had LAT resolution, 7 (28%) required TEE imaging >?6 months after index TEE to show clearance of thrombus. Rates of LAT resolution were similar between patients who had alterations in OAC and those who did not (52 vs. 60%; P?=?0.601).

Conclusions

After initial detection of left atrial thrombus despite uninterrupted anticoagulation for atrial fibrillation or flutter, >?40% patients have persistent clot despite additional extended anticoagulation.

     

Registo de encerramento percutâneo do apêndice auricular esquerdo e experiência inicial com ecografia intracardíaca

Introduction

Percutaneous closure of the left atrial appendage (LAA) is a promising therapy in patients with atrial fibrillation with high risk for stroke and contraindication for oral anticoagulation (OAC). Intracardiac echocardiography (ICE) may make this percutaneous procedure feasible in patients in whom transesophageal echocardiography (TEE) is inadvisable. Our aim was to assess the efficacy and safety of LAA closure and the feasibility of ICE compared to TEE to guide the procedure.

Left Atrial Appendage Closure for Stroke Prevention in Atrial Fibrillation

Purpose of Review

Anticoagulant therapy effectively reduces the incidence of stroke in patients with atrial fibrillation (AF) but is underutilized and frequently contraindicated. The left atrial appendage (LAA) is the primary site of thrombus formation in AF patients. Surgical and percutaneous appendage closure has been evaluated as a site-specific therapy to reduce systemic thromboembolism.

Recent Findings

We will review LAA closure techniques, examine recent outcome data, and discuss the indications for, and potential complications of, each approach.

Summary

Randomized data examining surgical LAA closure and epicardial closure with the LARIAT device are lacking. High quality, randomized data supports the efficacy of the WATCHMAN device for stroke prevention in patients with AF.

     

Bifocal right ventricular pacing: an alternative way to achieve resynchronization when left ventricular lead insertion is unsuccessful

Purpose

To explore the effects on atrial and ventricular function of restoring sinus rhythm (SR) after epicardial cryoablation and closure of the left atrial appendage (LAA) in patients with mitral valve disease and atrial fibrillation (AF) undergoing surgery.

Methods

Sixty-five patients with permanent AF were randomized to mitral valve surgery combined with left atrial epicardial cryoablation and LAA closure (ABL group, n?=?30) or to mitral valve surgery alone (control group, n?=?35). Two-dimensional and Doppler echocardiography were performed before and 6?months after surgery.

Results

At 6?months, 73% of the patients in the ABL group and 46% of the controls were in SR. Patients in SR at 6?months had a reduction in their left ventricular diastolic diameter while the left ventricular ejection fraction was unchanged. In patients remaining in AF, the left ventricular ejection fraction was lower than at baseline. The left atrial diastolic volume was reduced after surgery, more in patients with SR than AF. In patients in SR, the peak velocity during the atrial contraction and the reservoir function were lower in the ABL group than in the control group.

Conclusions

In patients in SR, signs of atrial dysfunction were observed in the ABL but not the control group. Atrial dysfunction may have existed before surgery, but the difference between the groups implies that the cryoablation procedure and/or closure of the LAA might have contributed.     

Un nuevo método no invasivo en la valoración integral de la fibrilación auricular por tomografía cardíaca

Objective:

To analyze the clinical utility and feasibility of the multidetector cardiac tomography (MDCT) in multi-parametric imaging assessment in atrial fibrillation (AF) patients.

Material and methods:

Prospective case-control study in 84 subjects (54 AF subjects and 30 healthy subjects). Left atrial appendage (LAA) morphology was classified as: cactus, chicken wing, wind sock, cauliflower. Intra-cardiac thrombus, stroke history and CHA₂DS₂-VASC scale were compared to cardiac MDCT atrial imaging assessment.

Results:

Left atrial ejection fraction (LAEF) and LAA ejection fraction (LAAEF) were lower in AF subjects (p < 0.001), left atrial volume index (LAVI) was higher in AF subjects (p < 0.001). An inverse correlation between LAEF and LAVI was found (r = −0.38, p < 0.001). Cauliflower LAA morphology frequency was higher in AF subjects, whereas cactus LAA morphology frequency was higher in controls. Cauliflower LAA morphology was associated with thrombus presence (p < 0.01) as well as a higher CHA₂DS₂-VASc score. Flow velocity were lower in AF subject compared to controls (p < 0.001).

Conclusion:

MDCT is a novel, non-invasive, worldwide available method for an integral assessment in AF. Our results could improve precision, clinical utility and risk stratification analysis in AF. Our proposal is to include this new method into the global cardiovascular and thrombotic risk assessment in AF patients.Key words: Multidetector cardiac tomography, Atrial fibrillation, Atrial function, Left atrial appendage, Flow velocity     

Fibrosis and electrophysiological characteristics of the atrial appendage in patients with atrial fibrillation and structural heart disease

Purpose

This study was conducted to investigate the degree of fibrosis in atrial appendages of patients with and without atrial fibrillation (AF) undergoing cardiac surgery. In addition, we hypothesized that areas of atrial fibrosis can be identified by electrogram fractionation and low voltage for potential ablation therapy.

Methods

Interstitial fibrosis from right (RAA) and/or left atrial appendages (LAA) was studied in patients with sinus rhythm (SR, n?=?8), paroxysmal (n?=?21), and persistent AF (n?=?20) undergoing coronary artery bypass and/or aortic or mitral valve surgery. Atrial fibrosis quantification was performed with Masson trichrome staining. Intraoperative bipolar epicardial electrophysiological measurements were performed to correlate fibrosis to electrogram fractionation, voltage, and AF cycle length.

Results

The average degree of fibrosis was 11.2?±?7.2 % in the LAA and 22.8?±?7.6 % in the RAA (p?<?0.001). Fibrosis was not significantly higher in paroxysmal AF patients compared to SR subjects (18.2?±?8.7 versus 20.7?±?5.3 %). Persistent AF patients had a higher degree of LAA and RAA fibrosis compared to paroxysmal AF patients (LAA 14.6?±?8.7 versus 8.6?±?4.7 %, p?=?0.02, and RAA 28.2?±?7.9 versus 18.2?±?8.7 %, respectively, p?=?0.04). The left atrial end diastolic volume index was higher in persistent AF patients compared to SR controls (38.3?±?16.4 and 28?±?11 ml/m², respectively, p?=?0.04). No correlation between atrial fibrosis and electrogram fractionation or voltage was found.

Conclusion

Patients with structural heart disease undergoing cardiac surgery have more fibrosis in the RAA than in the LAA. Furthermore, RAA fibrosis is increased in persistent AF but not paroxysmal AF patients compared to control subjects. Electrogram fractionation and low voltage did not provide accurate identification of the fibrotic substrate.     

Routine preprocedural transesophageal echocardiography might not be necessary for stroke prevention evaluation in AF patients on anticoagulation therapy

Background

Preprocedural transesophageal echocardiography (TEE) is used to reduce the stroke during atrial fibrillation (AF) ablation. This study evaluated whether routine preprocedural TEE in addition to multidetector computed tomography (MDCT) is necessary to prevent periprocedural stroke in AF ablation.

Methods

Each patient underwent MDCT and TEE (group 1, n = 247) or MDCT alone (group 2, n = 103) for the initial evaluation before AF ablation. In group 2, TEE was performed only in patients who had left atrial (LA) thrombus or blood stasis in MDCT.

Results

There was no difference in sex, CHADS₂ score, or LA dimension between the two groups. In group 1, a thrombus was detected in 12 (5%) and 6 (2%) patients by the MDCT and TEE, respectively. All (100%) patients, who were revealed to have thrombus in TEE, also had a thrombus in MDCT. In group 2, 3 (3%) patients exhibited LA thrombus in MDCT, among whom thrombus was observed in only one patient (1%) in TEE. AF ablation was not performed in patients with thrombus. While one patient had a periprocedural stroke in group 1, no patient had in group 2 (P = 0.52).

Conclusion

The overall periprocedural stroke rate was low (0.3%) in AF patients on anticoagulation therapy. The preprocedural MDCT detected all patients with the LA thrombus. In AF patients with low CHADS2 score, optimal anticoagulation and relatively preserved left ventricular ejection fraction, routine preprocedural TEE in addition to the MDCT might not be necessary to decrease the periprocedural stroke rate.     

Assessment and Management of the Left Atrial Appendage Thrombus in Patients With Nonvalvular Atrial Fibrillation

Background

Intracardiac thrombi arising in the left atrial appendage (LAA) are the principal cause of stroke in nonvalvular atrial fibrillation (AF). Predicting the presence of LAA thrombi is of vital importance in stratifying patients that would need further LAA imaging prior to cardioversion or AF ablation.

Prevalence and Clinical Characteristics Associated With Left Atrial Appendage Thrombus in Fully Anticoagulated Patients Undergoing Catheter‐Directed Atrial Fibrillation Ablation

LAA Thrombus Among Anticoagulated AF Patients. Introduction: Catheter‐directed atrial fibrillation (AF) ablation is contraindicated among patients with left atrial appendage (LAA) thrombus. The prevalence of LAA thrombus among fully anticoagulated patients undergoing AF ablation is unknown. Methods and Results: We retrospectively evaluated the prevalence of LAA thrombus among 192 consecutive patients undergoing AF ablation between July 2006 and January 2009. Seven of 192 patients (3.6%) had evidence of thrombus on transesophageal echocardiogram (TEE) despite being fully anticoagulated on warfarin (international normalized ratio [INR] 2–3) for 4 consecutive weeks prior to echocardiogram. Univariate analysis demonstrated that structural heart disease, large left atrial dimension, and number of AF ablations were associated with thrombus. Three patients with thrombus had paroxysmal AF with normal LV function. Conclusion: Despite full anticoagulation, 3.6% of patients undergoing AF ablation had LAA thrombus. We recommend that all patients, regardless of LV function or left atrial size, should undergo preprocedural TEE to exclude the presence of LAA thrombus. (J Cardiovasc Electrophysiol, Vol. 21, pp. 849‐852, August 2010)     

The impact of the CartoSound® image directly acquired from the left atrium for integration in atrial fibrillation ablation

Purpose

Intracardiac echocardiographic (ICE) imaging might be useful for integrating three-dimensional computed tomographic (CT) images for left atrial (LA) catheter navigation during atrial fibrillation (AF) ablation. However, the optimal CT image integration method using ICE has not been established.

Methods

This study included 52 AF patients who underwent successful circumferential pulmonary vein isolation (CPVI). In all patients, CT image integration was performed after the CPVI with the following two methods: (1) using ICE images of the LA derived from the right atrium and right ventricular outflow tract (RA-merge) and (2) using ICE images of the LA directly derived from the LA added to the image for the RA-merge (LA-merge). The accuracy of these two methods was assessed by the distances between the integrated CT image and ICE image (ICE-to-CT distance), and between the CT image and actual ablated sites for the CPVI (CT-to-ABL distance).

Results

The mean ICE-to-CT distance was comparable between the two methods (RA-merge?=?1.6?±?0.5 mm, LA-merge?=?1.7?±?0.4 mm; p?=?0.33). However, the mean CT-to-ABL distance was shorter for the LA-merge (2.1?±?0.6 mm) than RA-merge (2.5?±?0.8 mm; p?<?0.01). The LA, especially the left-sided PVs and LA roof, was more sharply delineated by direct LA imaging, and whereas the greatest CT-to-ABL distance was observed at the roof portion of the left superior PV (3.7?±?2.8 mm) after the RA-merge, it improved to 2.6?±?1.9 mm after the LA-merge (p?<?0.01).

Conclusions

Additional ICE images of the LA directly acquired from the LA might lead to a greater accuracy of the CT image integration for the CVPI.

     

Direct current cardioversion practices following percutaneous left atrial appendage closure

Introduction

Among patients with non-valvular atrial fibrillation (AF) and percutaneous left atrial appendage closure (LAAC) undergoing direct current cardioversion (DCCV), the need for and use of LAA imaging and oral anticoagulation (OAC) is unclear.

Objective

The purpose of this study is to evaluate the real-world use of transesophageal echocardiography (TEE) or cardiac computed tomography angiography (CCTA) before DCCV and use of OAC pre- and post-DCCV in patients with AF status post percutaneous LAAC.

Methods

This retrospective single center study included all patients who underwent DCCV after percutaneous LAAC from 2016 to 2022. Key measures were completion of TEE or CCTA pre-DCCV, OAC use pre- and post-DCCV, incidence of left atrial thrombus (LAT) or device-related thrombus (DRT), incidence of peri-device leak (PDL), and DCCV-related complications (stroke, systemic embolism, device embolization, major bleeding, or death) within 30 days.

Results

A total of 76 patients with AF and LAAC underwent 122 cases of DCCV. LAAC consisted of 47 (62%), 28 (37%), and 1 (1%) case of Watchman 2.5, Watchman FLX, and Lariat, respectively. Among the 122 DCCV cases, 31 (25%) cases were identified as “non-guideline based” due to: (1) no OAC for 3 weeks and no LAA imaging within 48 h before DCCV in 12 (10%) cases, (2) no OAC for 4 weeks following DCCV in 16 (13%) cases, or (3) both in 3 (2%) cases. Among the 70 (57%) cases that underwent TEE or CCTA before DCCV, 16 (23%) cases had a PDL with a mean size of 3.0 ± 1.1 mm, and 4 (6%) cases had a LAT/DRT on TEE resulting in cancellation. There were no DCCV-related complications within 30 days.

Discussion

There is a widely varied practice pattern of TEE, CCTA, and OAC use with DCCV after LAAC, with a 6% rate of LAT/DRT. LAA imaging before DCCV appears prudent in all cases, especially within 1 year of LAAC, to assess for device position, PDL, and LAT/DRT.     

Predictors of left atrium appendage clot detection despite on-target warfarin prevention for atrial fibrillation

Background and purpose

The antithrombotic management of atrial fibrillation (AF) is currently based on clinical scores (CHADS₂ or CHA₂DS₂VASc). The prevalence of left atrium (LA) thrombi in effectively anticoagulated AF patients has been reported as being up to 7.7 %. We tried to correlate LA/LA appendage (LAA) thrombus detection with possible clinical predictors in warfarin-treated patients.

Methods

We performed trans-esophageal echocardiography on 430 patients (mean age, 60.3?±?9.8 years) receiving oral anticoagulant (OAC) therapy and undergoing pulmonary vein isolation. In 10/430 (2.3 %), an LA thrombus was found despite therapeutic OAC (mean INR 2.6?±?0.6; range, 2.0–3.8) over the previous 4 weeks.

Results

Two study groups were identified:

1. T-positive group?=?with LAA thrombus (10 patients)
2. T-negative group?=?without LAA thrombus (420 patients)

The T-positive patients had a higher CHADS₂ score (1.5?±?0.7 versus 0.7?±?0.8; p?=?0.004), a lower LVEF (54.7?±?9.5 % versus 60.2?±?7.4; p?=?0.02), and a larger LA size (LA diameter, 56?±?12.2 mm versus 46?±?6.5 mm; p? <?0.001and normalized LA volume: 140.2?±?66 ml/m² vs. 67?±?39 ml/m²; p?<?0.05). On multivariate analysis, a larger LA diameter and normalized LA volume (OR, 1.14; 95 % C.I., 1.04–1.26; p?=?0.006 and OR, 1.02; 95 % C.I., 1.01–1.03; p?=?0.001, respectively) and a higher CHA₂DS₂VASc score (OR, 2.4; 95 % C.I., 1.4–4.2; p?=?0.001) predicted left atrium appendage (LAA) thrombus. In another 42/430 (9.8 %) patients, an LA spontaneous echo-contrast (SEC) was detected. Thus, cumulatively, 52/430 (12.1 %) patients had either LAA thrombi (10 patients) or SEC (42 patients). LA diameter continued to predict the presence of either thrombi or SEC (OR, 1.14; 95 % C.I., 1.07–1.2; p?<?0.05).

Conclusions

We found a 2.3 % prevalence of LA thrombus (12.1 % when SEC was also considered). The thrombus was present despite on-target warfarin prevention. In addition to a higher CHA₂DS₂VASc score, a larger LA size was a strong predictor of clot detection.     

Left atrial appendage obliteration in atrial fibrillation patients undergoing bioprosthetic mitral valve replacement

Background

Left atrial appendage (LAA) obliteration is a proven stroke-preventive measure for patients with nonvalvular atrial fibrillation (AF). However, the efficacy of LAA obliteration for patients with AF after bioprosthetic mitral valve replacement (MVR) remains unclear.

Aim

This study aimed to estimate the efficacy of LAA obliteration in preventing embolism and to investigate the predictors of thromboembolism after bioprosthetic MVR.

Methods

We retrospectively studied 173 AF subjects with bioprosthetic MVR; among them, 81 subjects underwent LAA obliteration using an endocardial running suture method. The main outcome measure was the occurrence of thrombosis events (TEs). The mean follow-up time was 40?±?17 months.

Results

AF rhythm was observed in 136 patients postoperatively. The incidence rate of TEs was 13.97?% for postoperative AF subjects; a dilated left atrium (LA; >?49.5 mm) was identified as an independent risk factor of TEs (OR?=?10.619, 95?% CI?=?2.754–40.94, p?=?0.001). For postoperative AF patients with or without LAA, the incidence rate of TEs was 15.8?% (9/57) and 12.7?% (10/79; p?=?0.603), respectively. The incidence rate of TEs was 2.7?% (1/36) and 4.2?% (2/48) for the subgroup patients with a left atrial diameter of <?49.5 mm, and 38.1?% (8/21) and 25.8?% (8/31) for those with a left atrial diameter of >?49.5 mm (p?=?0.346).

Conclusion

Surgical LAA obliteration in patients with valvular AF undergoing bioprosthetic MVR did not reduce TEs, even when the CHA₂DS₂-VASc score (a score for estimating the risk of stroke in AF) was ≥?2 points.

     

Study on the correlation between false-positive filling defect in LAA CT and LAA structure in patients with atrial fibrillation based on TEE

Objective

This study aims to explore the actual meaning of “false positive filling defect” in left atrial appendage (LAA) computed tomography (CT) in patients with atrial fibrillation (AF), with transesophageal echocardiography (TEE) as the gold standard.

Methods

Patients with AF undergoing cardiac CT angiography and TEE examinations for proposed radiofrequency catheter ablation between October 2020 and October 2021 were selected as the study subjects. Transesophageal echocardiography was taken as the “gold standard,” and spontaneous echocardiographic contrast (SEC) and thrombus events were defined as positive events. The CT manifestations were classified into three groups (true positive, false positive, and true negative) to evaluate the differences in left atrium (LA) anterior–posterior diameter (LAAP), LA anterior wall thickness, and LAA orifice long diameter and short diameter, area, and depth between the three groups.

Results

(1) There was no statistical difference in LA anterior wall thickness between the three groups (p > .05); there was a statistical difference in LAAP (only) between the true-positive group and the true-negative group (p < .05). (2) There was a statistical difference in LAA orifice long diameter, short diameter, and area between the true-positive group and the true-negative group as well as between the false-positive group and the true-negative group (p < .05). (3) There was a statistical difference in LAA depth between the true-positive group and the false-positive group as well as between the true-positive group and the true-negative group (p < .05). (4) The area under the receiver operator characteristic curve (AUC) of LAA depth affecting the LAA thrombus and SEC was 0.863 (confidence interval = 0.718–1.000), the sensitivity was 77.8%, and the specificity was 90.6% for predicting the occurrence of LAA thrombus and SEC in patients with nonvalvular AF (NVAF) and an LAA depth of ≥50.84 mm.

Conclusions

There was a difference in LAA diameter between the TEE-based CT false-positive group and the other groups. A “CT false positive” is an objectively existing state, and CT might be able to identify the LAA hemodynamic disorder earlier than TEE. Furthermore, a CT + TEE combined application could more accurately evaluate LAA hemodynamics in patients with AF.     

Impact of left atrial appendage ridge ablation on the complex fractionated electrograms in persistent atrial fibrillation

Background

The left atrial appendage (LAA) is a possible key contributor to the maintenance of persistent atrial fibrillation (PsAF). The effect of LAA ostial ablation on global left atrial higher-frequency sources remains unclear.

Methods

Complex fractionated electrograms (CFEs) and dominant frequency (DF) maps acquired with a NavX system in 58 PsAF patients were enrolled and examined before and after LAA posterior ridge ablation, which followed a stepwise linear ablation.

Results

High-density left atrial mapping identified continuous CFE sites in 50 % and high-DFs (≥8 Hz) in 53 % of patients at the LAA posterior ridge. In 44 patients in whom AF persisted despite pulmonary vein isolation (PVI) and linear ablation, LAA ablation significantly increased the mean CFE cycle length from 98?±?29 to 108?±?30 ms (P?P?90 mL/m²) (median 0 vs 4.8 %; P?P?Conclusion These findings suggested that an approach incorporating an LAA posterior ridge ablation was effective in modifying higher-frequency sources in the global LA in PsAF patients, but a lesser effect was documented in patients with electroanatomical remodeling of the LA.     

Relation between left atrial measurements and thromboembolic risk markers assessed by echocardiography in patients with nonvalvular atrial fibrillation: A cross-sectional study

Background

Left atrium (LA) dilatation has been associated with adverse cardiovascular outcomes in patients with sinus rhythm and atrial fibrillation (AF).

Device-Related Thrombosis After Percutaneous Left Atrial Appendage Occlusion for Atrial Fibrillation

Background

Transcatheter left atrial appendage (LAA) occlusion is an alternative strategy for stroke prevention in patients with atrial fibrillation (AF).