Left Atrial Appendage Morphology Research Articles

P1799 The importance of 3D imaging techniques in left atrial appendage closure: landing zone eccentricity influence on peri-device leak incidence and its implication in long-term clinical outcomes

Abstract Background A complex left atrial appendage (LAA) morphology and a non-circular landing zone (LZ) are frequently encountered in patients undergoing percutaneous LAA occlusion (LAAO). Three-dimensional (3D) imaging modalities as 3D transoesophageal echocardiography (3D TOE) and cardiac computed tomography (CCT) should be preferred over two dimensional techniques for better evaluation of LAA diameters, especially for the LZ. In fact, non-circular shape could impair the choice of occluder device size and may be implicated in the occurrence of residual leaks. Incomplete LAA occlusion is recognized to be associated with thromboembolic events. Purpose The aim of the study was to evaluate the utility of 3D imaging techniques to predict LAA device size and the landing zone eccentricity index as a potential predictor of residual peri-device leaks and to assess their clinical implications on long-term follow-up. Methods It was a retrospective, single-center study including 137 consecutive patients undergoing successful LAAO from January 2010 to July 2018. Pre-procedural 3D TOE and CCT were used to predict device size based upon LZ diameters and quantify LAA orifice eccentricity. Leaks were defined as the presence of peri-device flow at 2D TOE immediately after the device implantation and at 3 months follow-up. Leaks were classified as significant (color jet width ≥4 mm) or minor (<3 mm). A clinical evaluation of thromboembolic events was performed at 48 ± 27 months from the procedure. Results LAAO closure was performed implanting either Amulet or Watchman devices (n = 98 and n = 40, respectively). The assessment of LZ measurements with 3D TOE and CCT showed a significant correlation with the device size selected on the basis of 2D techniques (r = 0.82 and r = 0.74, respectively). As concerns the peri-device leaks, the presence of an eccentric LZ (eccentricity index >0.20) was not associated to the development of post-procedural leaks in the overall population; a significant correlation was detected only in the subgroup of patients treated with the Amulet device (p = 0.045). Residual leaks included only 1 significant leak (0.7%) after Amulet device implantation, which was related to a major neurological event (stroke) and 47 (34%) minor leaks (n = 28 in the Amulet group, n = 19 in the Watchman group). In this last population, 2 patients (1.5%) developed minor neurological events (transient ischemic attack). Conclusions 3D TOE and CCT better predict device size overcoming the limit of 2D imaging techniques undersizing. In eccentric LAA, Watchman device may reduce the incidence of peri-device leaks. The presence of significant residual leaks is uncommon but associated with major clinical events, whilst minor leaks are relatively frequent but do not seem to be related to life-threatining thromboembolic accidents.

Vascular Landmark-Based Method for Highly Reproducible Measurement of Left Atrial Appendage Volume in Computed Tomography.

Modern computed tomographic scanning can produce 4-dimensional images of the left atrial appendage (LAA). LAA function and morphology can then be measured, to plan interventions such as occlusion and to evaluate LAA flow for thrombogenic risk analysis. A current problem here is defining a reproducible boundary between the LAA and the left atrium. This study used retrospectively gated 4-dimensional computed tomographic data from 25 implantation and coronary artery imaging patients. In each patient, the LAA ostium was defined at multiple time points during the RR interval. To examine the reproducibility of the definition of the LAA ostium, 3 observers analyzed all time frames in each patient 3 times. Five nonconsecutive time frames from each patient were then compared using intraclass correlation coefficients to quantify the precision of the method across patients. The correlation of LAA volumes for each time frame of each patient was determined across the different observers (interobserver) and within each observer's own data sets (intraobserver). The method was successful in 92% of patients. Two-way random-effect, absolute-agreement, single-measurement intraclass correlation coefficients for interobserver measurements were 0.984, 0.990, and 0.988, with intraobserver intraclass correlation coefficients of 0.989, 0.989, and 0.995. The intraclass correlation coefficient of all observations was 0.988. Classification of the LAA ostium using a stepwise procedure identifying the coumadin ridge and 2 vascular landmarks in ECG-gated computed tomography provides a viable method of establishing a highly reproducible boundary between the atrium and LAA needed to obtain LAA metrics useful for procedure planning and measuring LAA function.

Comparison of echocardiographic and fluoroscopic sizing of the left atrial appendage prior to percutaneous closure.

Sizing of the left atrial appendage (LAA) ostium prior to occlusion (LAAO) is routinely performed with transesophageal echocardiography (TEE). We sought to compare the utility of sizing via fluoroscopy to TEE for percutaneous LAAO. We retrospectively evaluated all patients undergoing percutaneous LAAO at our institution from April 2015 through January 2018 (n = 195). We evaluated baseline characteristics, maximum measured ostium size (for both TEE and fluoroscopy), and differences in measured size to device size for both techniques. Of the total cohort, 185 (95%) had both intraoperative TEE and fluoroscopic images available for analysis and were included in the final analysis. The mean age was 74years and 64% were male. Hypertension was present in 89%, diabetes in 30%, and stroke in 32% of patients. The mean ejection fraction was 51%. The most common LAA morphology was "wind sock" (52%). Measured ostial diameter on fluoroscopy was larger compared with TEE (2.04 ± 3.43mm larger on fluoroscopy, p < 0.001). Ostium diameter on TEE was more closely correlated to the size of the device implanted compared with fluoroscopy (0.76 vs. 0.61, p = 0.001). Fluoroscopy results in larger estimated LAA ostium diameter compared with TEE. Despite this, TEE was more strongly correlated to operator choice in device sizing, which may reflect practice patterns. Because compression of the ostium on the device is necessary for long-term procedural success, under-sizing may lead to a higher rate of leaks. Prospective evaluation of the utility of routine fluoroscopic sizing compared with TEE is warranted.

P3383Left atrial appendage and left atrial morphology is associated with cryptogenic stroke

Abstract Background Stroke causes a high burden of morbidity and mortality worldwide. Approximately 30% of stroke cases remain cryptogenic (CS), of which one third is due to occult atrial fibrillation (AF) with left atrial appendage (LAA) being the most frequent thrombus source. Hence, aim of our study was to assess if LAA morphological parameters analysed by computed tomography angiography (CTA) are associated with CS. Methods and materials In 184 patients (Table 1), 82 CS patients and 102 controls (age median 62 (52,2–72), 40.2% females), matched for BMI, a CTA was performed, and LAA morphology evaluated retrospectively. LAA morphology was classified into 5 types (Figure 1): Cactus, Cauliflower, Chicken-wing, Windsock and the new “Seahorse” with a distinctive tip angulation of ≤90° and 2 bends (Z-shape). Further measurements included: LAA tip angulation (≤90°, 91–110°, &gt;110°), LAA lobe number, LAA ostium size (length) and angulation, left atrium wall thickness (LAWT). Results LAA and left atrium (LA) parameters associated with CS on multivariable analysis after adjusting for CHA2DS2-VASc score were: Chicken-wing type (OR 2.15; 95% CI: 1.01–4.56, p=0.046), a greater lobe number (OR 2.01; 95% CI: 1.52–2.64, p&lt;0.001), a greater middle and mean LAWT (respectively, OR 2.13; 95% CI: 1.49–3.05, p&lt;0.001, OR 2.64; 95% CI: 1.63–4.29, p&lt;0.001), a larger (length, OR 1.08; 95% CI: 1.0–1.16, p=0.039) and a less bent LAA ostium (OR 1.02; 95% CI: 1.01–1.03, p=0.006). In contrast, a sharp-angled LAA tip (≤90°) was protective from CS (OR 0.43; 95% CI: 0.23–0.83, p=0.012) on multivariable analysis. Table1. Clinical patient characteristics CS (n=82) Non-stroke (n=102) p value Females 21 (25.6%) 53 (52%) p&lt;0.001 Age, y 66.5 (57–73) 57.5 (50–70) 0.001 BMI, kg/m2 25.6 (23.9–28.2) 26 (23.3–30.1) 0.320 CHA2DS2-VASc score 2 (1–3) 2 (1–3) 0.387 AF (paroxysmal/permanent) 0 4 0.071 Hypertension 68 (82.9%) 54 (56.3%) p&lt;0.001 Diabetes mellitus, type 2 16 (19.8%) 11 (11.5%) 0.145 Values are given in median ± IQR. AF, atrial fibrillation; BMI, body mass index. LAA and LA morphology in CTA. Conclusion In CS, a Chicken-wing LAA, a greater number of lobes and a thicker LA wall are independently associated with CS while a sharp LAA tip (≤90°) mostly seen in Seahorse type LAA is protective. Such “high-risk” LAA and LA morphology could help to select CS patients benefiting from extended rhythm-monitoring to detect an occult AF, however, further prospective studies are needed to confirm this hypothesis.

Left Atrial Appendage Morphology as a Determinant for Stroke Risk Assessment in Atrial Fibrillation Patients: Systematic Review and Meta-Analysis.

Atrial fibrillation (AF) is a leading source of emboli that precipitate cerebrovascular accident (CVA) which is correlated with left atrial appendage (LAA) morphology. We aimed to elaborate the relationship between CVA and LAA morphology in AF patients. Medline and EMBASE databases were thoroughly searched between 2010-2018 for studies that included atrial fibrillation patients and classified them into two groups based on CVA occurrence. Four different LAA morphologies (Chicken wing CW, Cauliflower, cactus and windsock) were determined in each group by 3D TEE, MDCT or CMRI. New Castle Ottawa Scale was used to appraise the quality of included studies. The risk of CVA before cardiac ablation and/or LAA intervention in CW patients was compared to each type of non-CW morphologies. The extracted data was statistically analyzed in the form of forest plot by measuring the risk ratio (RR) using REVMAN software. P value and I square were used to assess the heterogeneity between studies. PRISMA diagram was illustrated showing 789 imported studies for screening. Three duplicates were removed, and the rest were arbitrated by 2 reviewers yielding 12 included studies with 3486 patients including 1551 with CW, 442 with cauliflower, 732 with cactus 765 with windsock. The risk of CVA in CW patients was reduced by 41% relative to non-CW patients (Total RR=0.59 (0.52-0.68)). Likewise, the risk of CVA in CW patients was less by 46%, 35% and 31% compared to cauliflower (Total RR =0.54(0.46-0.64)), cactus (Total RR =0.65(0.55-0.77)) and windsock (Total RR =0.69(0.58-0.83)) patients respectively. Low levels of heterogeneity were achieved in all comparisons (I square <35% and p value > 0.1). Patients with non-CW morphologies (cauliflower, cactus and windsock) show a higher incidence of CVA than CW patients. For that reason, LAA appendage morphology could be useful for risk stratification of CVA in AF patients.

Stroke Risk in Atrial Fibrillation: Beyond the CHA2DS2-VASc Score.

Stroke prevention is the cornerstone of atrial fibrillation (AF) management and the anticoagulation decision is currently based on CHA2DS2-VASc risk score. We discuss several novel risk factors besides those included in CHA2DS2-VASc score and alternative models for stroke prediction. Several clinical markers including obstructive sleep apnea and renal failure, laboratory markers like brain natriuretic peptide, imaging criteria including left atrial appendage morphology, spontaneous echo contrast, and coronary artery calcium score may predict stroke in AF patients. Addition of African American ethnicity to CHA2DS2-VASc score also improves stroke prediction in AF. Finally, novel models including TIMI-AF score, ATRIA score, and GARFIELD-AF scores have potential roles in risk stratification for stroke. While CHA2DS2-VASc score is the currently recommended risk stratification model for stroke prediction in AF, use of additional clinical, laboratory, imaging markers, ethnicity, and novel stroke prediction models may further assist in decision to anticoagulate the AF patient for stroke prevention.

Simultaneous Functional and Morphological Assessment of Left Atrial Appendage by 3D Virtual Models.

Purpose The left atrial appendage (LAA) is responsible for thrombus formation in patients with atrial fibrillation. The evaluation of both LAA function and morphology is crucial for the patient characterization and the preprocedural planning of LAA closure intervention. Despite the availability of 3D imaging modalities, the current standard image analysis is based on manual delineation of the LAA contours on 2D views. Methods In this study, a comprehensive approach based on a full 3D analysis of the tomographic dataset by surface extraction and processing (3D-S) is presented. The proposed method allows extracting functional and morphologic information in the entire cardiac cycle by minimalizing manual user interaction. The proposed methodology has been validated on ten computer tomography datasets. Results The proposed 3D-S method was feasible in all cases. Reproducibility was improved with respect to the reference 2D manual procedure (2D-S) (coefficient of variation 2.9 vs. 4.1% for diastolic ostium area; 3.8 vs. 6.1% for systolic ostium area; 2.4 vs. 5.3% for diastolic LAA volume; 2.7 vs. 5.9% for systolic LAA volume; and 7.7 vs. 17.1% for LAA ejection fraction). No significant differences were found between 2D-S and 3D-S measurements. Conclusions In this study, we introduced a fully 3D approach for LAA characterization, allowing the simultaneous assessment of LAA function and geometry. The proposed approach could be used to improve the patient selection and the best sizing of the device for LAA closure and to allow a patient-specific 3D printing.

The left atrial appendage morphology is associated with embolic stroke subtypes using a simple classification system: A proof of concept study

Background and purposeThe current left atrial appendage (LAA) classification system (cLAA-CS) categorizes it into 4 morphologies: chicken wing (CW), windsock, cactus, and cauliflower, though there is limited data on either reliability or associations between different morphologies and stroke risk. We aimed to develop a simplified LAA classification system and to determine its relationship to embolic stroke subtypes. MethodsConsecutive patients with ischemic stroke from a prospective stroke registry who previously underwent a clinically-indicated chest CT were included. Stroke subtype was determined and LAA morphology was classified using the traditional system (in which CW = low risk) and a new system (LAA-H/L, in which low risk morphology (LAA-L) was defined as an acute angle bend or fold from the proximal/middle portion of the LAA and high risk morphology (LAA-H) was defined as all others). As a proof of concept study, we determined reliability for the two classification systems, and we assessed the associations between both classification systems with stroke subtypes in our cohort and previous studies. ResultsWe identified 329 ischemic stroke patients with a qualifying chest CT (126 cardioembolic subtype, 116 embolic stroke of undetermined source (ESUS), and 87 non-cardioembolic subtypes). Intra- and inter-rater agreements improved using the LAA-H/L (0.95 and 0.85, respectively) vs. cLAA-CS (0.50 and 0.40). The LAA-H/L led to classifying 69 LAA morphologies that met criteria for CW as LAA-H. In fully adjusted models, LAA-H was associated with cardioembolic stroke (OR 5.4, 95%CI 2.1–13.7) and ESUS (OR 2.8 95% CI 1.2–6.4). Non-CW morphology was also associated with embolic stroke subtypes, but the effect size was much less pronounced. Studies using the cLAA-CS yielded mixed results for inter- and intra-rater agreements but most showed an association between a non-CW morphology and stroke with no difference among the three non-CW subtypes. ConclusionThe LAA-H/L classification system is simple, has excellent intra and inter-rater agreements, and may help risk identify patients with cardioembolic stroke subtypes. Larger studies are needed to validate these findings.

Percutaneous closure of the left atrial appendage: The value of real time 3D transesophageal echocardiography and the intraoperative change in the size of the left atrial appendage.

The aim of this study was to investigate the value of real time three-dimensional transesophageal echocardiography (RT3DTEE) in percutaneous closure of the left atrial appendage (LAAC). In addition, this study also explored the change in the size of the left atrial appendage (LAA) from 24hours before the operation to just before implantation during the operation. In a retrospective study, 32 patients underwent two-dimensional transesophageal echocardiography (2DTEE) and RT3DTEE 24hours prior to operation and during operation. The maximal LAA orifice diameter (by 2DTEE, 22.7±2.7 vs 24.6±2.2mm, P<0.01; by RT3DTEE, 24.2±2.9 vs 25.8±2.7mm, P<0.01), the maximal landing zone diameter (by 2DTEE, 19.0±2.8 vs 20.4±2.8mm, P<0.01; by RT3DTEE, 20.4±2.7 vs 22.6±3.0mm, P<0.01), and the maximal depth diameter (by 2DTEE, 25.2±3.2 vs 26.5±3.0mm, P<0.01; by RT3DTEE, 26.4±3.2 vs 27.5±3.7mm, P<0.01) all increased significantly during the operation. The highest correlation (R) between the maximal landing zone diameter and the compressed occluder diameter was determined for RT3DTEE measurements during the operation (R=0.90), whereas the landing zone diameter (R=0.80) measured by 2DTEE was less correlated. In addition, our study showed that RT3DTEE was of great value in discriminating the LAA orifice shape, allowing differentiation of the LAA morphology and identification of the number of LAA lobes. A certain amount of intravenous rehydration just before and during operation increased the LAA size significantly. The measurements by RT3DTEE showed a closer correlation to LAA occluder size than those by 2DTEE. The LAA displayed by RT3DTEE was more visible than that by 2DTEE.

Abstract 126: A Simple Classification of the Left Atrial Appendage Morphology Based on Stroke Risk: The LAA H/L Classification System

Introduction: The left atrial appendage (LAA) morphology is classified into 4 categories: chicken wing (CW), windsock, cactus, and cauliflower (cLAA-CS) (Figure) without established inter and intra-rater agreements. We aim to determine intra-rater and inter-rater agreements and relationship with embolic stroke subtypes using a new classification system vs. cLAA-CS. Methods: Consecutive patients with ischemic stroke from a prospective stroke registry who previously underwent a clinically-indicated chest CT were included. Stroke subtype was determined and LAA morphology were classified using the cLAA-CS (CW=low risk) and the new LAA-H/L system [Low risk morphology (LAA-L) defined an acute angle bend or fold from the proximal/middle portion of the LAA and LAA-H defined as all others]. We determined intra and inter-rater agreements for the two classification systems and the association between non-CW and LAA-H morphologies with embolic subtypes in our cohort and stroke in previous studies. Results: We identified 329 patients with a qualifying chest CT performed (126 cardioembolic subtype, 116 ESUS, and 87 non-cardioembolic subtypes). Intra and inter-rater agreements improved using the LAA-H/L (0.95 and 0.85) vs. cLAA-CS (0.4 and 0.5). Using the LAA-H/L led to classifying 50 LAA morphologies that met criteria for CW as LAA-H (Figure). In fully adjusted models, LAA-H was associated with cardioembolic stroke (OR 5.4, 95%CI 2.1-13.7) and ESUS (OR 2.8 95% CI 1.2-6.4). Non-CW morphology was also associated with embolic stroke subtypes, but the effect size was much less pronounced. Studies using the cLAA-CS yielded mixed results for inter and intrarater agreements but most showed an association between a non-CW morphology and stroke with no difference among the three non-CW subtypes (Table). Conclusion: The LAA-H/L classification system is simple, has excellent intra and inter-rater agreements, and may help risk stratify patients at risk for cardioembolic stroke.

Abstract WMP72: High Risk Left Atrial Appendage Morphology (LAA-H) is Associated With Cardioembolic and Embolic Stroke of Unknown Source Subtypes

Background: The left atrial appendage (LAA) is the main source of thrombus in atrial fibrillation (AF); biomarkers of LAA dysfunction are associated with ischemic stroke (IS) risk in patients with AF. We hypothesized that high risk LAA features [High risk morphology (LAA-H), LAA volume (LAAV), and LAA orifice surface area (LAAOSA)] would be more prevalent among patients with cardioembolic (CE) stroke and embolic stroke of undetermined source (ESUS) than among those with non-cardioembolic stroke (NCS). Methods: Consecutive patients with IS from a prospective comprehensive stroke center registry who previously underwent a clinically-indicated qualifying chest CT were included. Patients underwent inpatient diagnostic evaluation for ischemic stroke, and stroke subtype was determined based on ESUS criteria. LAA morphology [Low risk morphology was defined as two lobes with an acute angle between them or chicken wing morphology and LAA-H defined as all others], LAAOSA (measured in a plane parallel to the left atrium), and LAAV (measured using a volumetric analysis software) were determined using contrast enhanced thin-slice chest CT (≤2.5 mm thickness) by investigators blinded to stroke subtype. Results: Of 1234 patients with ischemic stroke, 329 (26.7%) patients had a qualifying chest CT performed (126 CE, 116 ESUS, and 87 NCS). The baseline characteristics of patients with and without chest CT were similar. When compared to NCS, LAA-H was more prevalent in ESUS (86.4% vs. 70.1%, p=0.018) and CE stroke (82.5% vs. 70.1%, p=0.042). The LAAOSA and volume did not significantly differ between the 3 groups (Table). Conclusion: LAA characteristics associated with cardioembolic stroke are also more prevalent in patients with ESUS. Larger studies are needed to confirm that LAA features are a risk factor for stroke among patients without AF, and whether anticoagulation is effective in patients with high-risk LAA features.

Relation of Left Atrial Appendage Morphology Determined by Computed Tomography to Prior Stroke or to Increased Risk of Stroke in Patients With Atrial Fibrillation

Left atrial appendage (LAA) morphology is considered to be associated with ischemic stroke, non-Chicken Wing LAA morphology increases the risk of thromboembolic events. However, existing classification of LAA morphology remains not well quantifiable and therefore may leave room for substantial subjective interpretation. This study aimed to assess interobserver and intraobserver agreements in LAA morphology and its real value in stroke prediction. A total of 2,264 atrial fibrillation patients who underwent computed tomography to explore the LAA anatomy were enrolled. All computed tomography images were given to 3 reviewers to judge the LAA morphology independently. A consensus between all 3 reviewers was only reached in 655 cases (28.9%). In which, 86 patients had previous stroke. Poor intraobserver consistency was observed between 2 times of reading in all the 3 reviewers (Kappa = 0.368, p = 0.014; Kappa = 0.350, p = 0.014; Kappa = 0.333, p = 0.015). Multivariate analysis showed that persistent atrial fibrillation (odds ratio [OR] 1.679; 95% confidence interval [CI] 1.031 to 2.736; p = 0.037), female gender (OR 1.761; 95% CI 1.037 to 2.994; p = 0.036) and age (OR 1.029; 95% CI 1.004 to 1.056; p = 0.025) were associated with previous stroke. LAA morphology was not associated with previous stroke and non-Chicken Wing LAA morphology did not increase the risk of stroke (OR 1.392; 95% CI 0.847 to 2.288; p = 0.192). In conclusion, high interobserver and intraobserver variabilities suggested that existing classification of LAA morphology was unreliable, the interpretation of the relation between LAA morphology and stroke needs caution.

The Impact of Left Atrium Appendage Morphology on Stroke Risk Assessment in Atrial Fibrillation: A Computational Fluid Dynamics Study.

Atrial fibrillation (AF) carries out a 5-fold increase in stroke risk, related to embolization of thrombi clotting in left atrium (LA). Left atrial appendage (LAA) is the site with the highest blood stasis which causes thrombus formation. About 90 % of the intracardiac thrombi in patients with cardioembolic events originally develop in the LAA. Recent studies have been focused on the association between LAA anatomical features and stroke risk and provided conflicting results. Haemodynamic and fluid dynamic information on the LA and mostly on the LAA may improve stroke risk stratification. Therefore, the aim of this study was the design and development of a workflow to quantitatively define the influence of the LAA morphology on LA hemodynamics. Five 3D LA anatomical models, obtained from real clinical data, which were clearly different as regard to LAA morphology were used. For each LAA we identified and computed several parameters describing its geometry. Then, one LA chamber model was chosen and a framework was developed to connect the different LAAs belonging to the other four patients to this model. These new anatomical models represented the computational domain for the computational fluid dynamics (CFD) study; simulations of the hemodynamics within the LA and LAA were performed in order to evaluate the interplay of the LAA shape on the blood flow characteristics in AF condition. CFD simulations were carried out for five cardiac cycles. Blood velocity, vorticity, LAA orifice velocity, residence time computed in the five models were compared and correlated with LAA morphologies. Results showed that not only complex morphologies were characterized by low velocities, low vorticity and consequently could carry a higher thrombogenic risk; even qualitatively simple morphologies showed a thrombogenic risk equal, or even higher, than more complex auricles. CFD results supported the hypothesis that LAA geometric characteristics plays a key-role in defining thromboembolic risk. LAA geometric parameters could be considered, coupled with the morphological characteristics, for a comprehensive evaluation of the regional blood stasis. The proposed procedure might address the development of a tool for patient-specific stroke risk assessment and preventive treatment in AF patients, relying on morpho-functional defintion of each LAA type.

Impact of anatomical features of the left atrial appendage on outcomes after cryoablation for atrial fibrillation

AimsPulmonary vein isolation (PVI) using cryoballoon has been accepted as a safe and effective method for treatment of atrial fibrillation (AF). Despite advances in catheter-based technologies, some patients still experience AF recurrence. In this study, we aimed to compare left atrial appendage (LAA) morphology in AF patients and subjects with sinus rhythm and also investigate the association between LAA morphology and success of PVI using cryoballoon in subjects with AF. MethodsIn this prospective study, 359 AF patients who underwent pre-ablation computed tomographic angiography (CTA) scan between January 2013–March 2016 were included as the patient group. 100 age and gender-matched subjects in sinus rhythm who had no AF episodes in 24-h Holter monitoring that underwent CTA were included as the control group. ResultsNon-chicken wing LAA morphology was more common in AF patients (p < 0.001). LAA was significantly deeper (p < 0.001) and short-axis diameter of LAA orifice and LAA orifice area were significantly larger (p < 0.001) in AF patients. Low take-off type morphology of LAA was more common in controls compared to AF patients (p = 0.006). At a median follow-up of 37 months, only longitudinal-axis left atrial diameter on CT (p = 0.003) and cauliflower-type LAA morphology (p = 0.004) were independent predictors of AF recurrence. ConclusionThis is the first study in the literature that investigates the relationship between anatomical variations of LAA and AF recurrence following cryoablation. Our findings demonstrate that cauliflower-type LAA morphology is associated with two-fold increased risk of AF recurrence.

Association between Morphodynamic Variables by Transesophageal Echocardiography and CHA2DS2-Vasc Values

Abstract Background: In atrial fibrillation (AF), the CHA2DS2-VASc score calculates the risk for stroke. Di Biase classified the left atrial appendage (LAA), using magnetic resonance imaging, into 4 morphological types and correlated it with cerebrovascular events. Transesophageal echocardiography (TEE) also evaluates LAA and is a more widespread technique. Objective: To evaluate, using TEE, the possibility of characterizing LAA and to analyze its morphological aspects using the CHA2DS2VASc score. Methodology: A total of 247 patients were divided into three groups considering the CHA2DS2-VASc score: Group 1: 0 and 1; Group 2: 2 and 3 and, Group 3: ≥ 4 points. TEE produced the echocardiographic data. LAA was classified into thrombogenic and non-thrombogenic morphologies. In the analysis of statistical tests, a significance level of 5% was adopted. Results: The average age was 50 and 16.2% presented AF. In Group 1, we observed normal variables with a lower prevalence of AF (8.7%, p < 0.001). In group 2, spontaneous contrast was detected in 26.7%, (p < 0.001), thrombus in 6.7% (p = 0.079) and flow velocity in LAA < 0.4 m/s in 22.7% (p < 0.001) of the cases. Group 3 presented the highest percentages of AF (31.8%, p < 0.001), stroke/TIA (77.3%, p < 0.001), EF < 55% (18.2%, p = 0.010) and higher prevalence of thrombogenic type LAA (72.7%, p = 0.014). A higher occurrence of stroke/TIA was observed in patients with thrombogenic LAA (25.2%) compared to the non-thrombogenic group (11.2%), (p = 0.005). Conclusions: The thrombogenic morphology of LAA identified in TEE presented a higher risk of stroke regardless of the CHA2DS2VASc score. Patients with higher scores had greater abnormalities in echocardiographic variables.

Morphologic and functional features of left atrial appendage in Iranian population: an echocardiographic study.

Introduction: Cardioembolic events are accompanied by left atrial appendage (LAA) in patients suffering from atrial fibrillation (AF); therefore, the LAA closure is implemented as a preventive strategy. The detection of LAA morphologies and function is a paramount step before establishing the LAA closure. Herein, we sought to determine the morphologic features of the LAA in an Iranian population using echocardiographic evaluation. Methods: Seventy-two near-normal heart patients were investigated by conducting a cross-sectional study. All patients were examined using the 2-dimensional and 3-dimensional transesophageal echocardiography (2D- and 3D-TEE) method. The anatomical features and functions of LAA were examined. All images were stored and analyzed offline. Results: The patients’ mean age was 39 ± 15.5 year and 33 (45.8%) were female. The most frequent shape of LAA was wind sock . More LAA lobes was observed in patients with AF compared to those with NSR. In comparison with AF group, the NSR had higher LAA flow velocity (P < 0.01). The paroxysmal AF had greater LAA flow velocity and LAA ejection fraction in comparison with the chronic AF (39 ± 19 vs. 75 ± 22, P < 0.01; and 49±4 vs. 72±14, P < 0.003; respectively). The paroxysmal AF had smaller systolic LAA orifice area in comparison with the chronic AF (P < 0.02). Conclusion: The morphologic features of LAA in Iranian population were within the range of other studies and LAA length and orifice diameters in 2D- and 3D-TEE were consistent. In addition, AF influenced the morphologies and functions of LAA compared to sinus rhythm.

Left Atrial Appendage Mechanical Changes in Patient with Mitral Stenosis Speckle Tracking Imaging Study

Background: LAA is the major site of thrombus formation in mitral stenosis; active LAA blood flow and contractile function may be disturbed in MS. TEE is the modality of choice for evaluating LAA and Speckle-tracking echocardiography (STE) is a recently developed technique for the characterization and quantification of myocardial deformation. It permits measurement of LA and LAA strain and strain rate which can be used to assess the mechanical function of LAA. Objective: To assess the mechanical function of left atrial appendage (LAA) in mitral stenosis (MS) patients with sinus rhythm by 2D speckle tracking strain and strain rate through transesophageal echocardiography (TEE). Patients & Method: Thirty-three patients with moderate tosevere MS and sinus rhythm, 38.33 ± 5.66 years as a case group and twenty-two age and sex matched healthy volunteers as a control group. All participants underwent compete conventional transthoracic echocardiography; TEE for assessment of LAA morphology and Doppler flow and speckle tracking strain & strain rate were measured from LAA walls. Results: LAA Doppler flow peak velocities, LAA strain, reservoir strain rate (RSr), conduit strain rate (CSr) and atrial contractile strain rate (ASr) all were significantly lower in patient group. Global Strain of LAA had a negative correlation with LA diameter, pulmonary artery systolic pressure & degree of spontaneous echo contrast and a positive correlation with MS area and LAA Doppler flow.Conclusion: 2D speckle tracking strain and strain rate of LAA is a feasible technique and is significantly reduced in patients with mitral stenosis even with sinus rhythm.

Risk Scores for Stroke Prevention in Patients with Non-Valvular Atrial Prevention: Is it Time to Put Parameters of Left Atrial Appendage Morphology and Function Into Clinical Practice?

Risk Scores for Stroke Prevention in Patients with Non-Valvular Atrial Prevention: Is it Time to Put Parameters of Left Atrial Appendage Morphology and Function Into Clinical Practice?

Silent thrombosis of a WATCHMAN device after Left Atrial Appendage ClosureDate from the RESET registry

Left atrial appendage (LAA) closure (LAAC) is recommended in patients (pts) with non-valvular atrial fibrillation (AF) and a contra indication (CI) to long-term oral anticoagulation (OAC).We sought to determine incidence and risk factors for WATCHMAN device (WM) thrombosis. LAAC with a WM was done in 100 consecutive pts prospectively included in the monocentric RESET Registry. No thromboembolic event occurred. Transoesophageal echocardiography (TOE) was done in 57 pts at a median of 53 days (22–460) and Cardiac Computed Tomography Angiography (CCTA) in 62 at a median of 175 days (33–792). LAA thrombus against the device was detected by TOE or CCTA in 5 pts. We compared characteristics of the group with (DT) or without (N-DT) device thrombosis. A major bleeding was the CI for OAC in 77 pts (96%) and only 8 received anticoagulation for 45 days after LAAC. Thereafter, 58 received aspirin (73%), 20 no treatment (25%) and 2 an OAC. LAA thrombus was detected in 2 pts by TOE (51 and 98 days) and 3 by CCTA (178, 183 and 447 day) and resolved on OAC. Incidence at 1 year was 5.1% (4/78). No significant difference was observed between the 2 groups. Although DT had a tendency of higher CHA2DS2-VASc (5 ± 1.6 vs. 4.6 ± 1.4) or HAS-BLED (4.6 ± 0.5 vs. 4.4 ± 1) scores, permanent AF (60% vs. 48%), intracranial haemorrhage (80% vs. 48%), no difference in term of history of stroke/TIA (60% vs. 70%) or antiplatelet treatment (80% vs. 60%) was noted. Morphology of LAA was in all cases a non-chicken-wing (vs. 67%). Although LAAC is limited to patients with multiple comorbidities that are reluctant to TOE, incidence of LAA thrombosis after WM implantation is high enough to strongly recommend device surveillance. Nevertheless, the optimal timing for imaging remains unclear and repetitive studies could be necessary in specific conditions. Medical history and morphologic characteristics of LAA are of limited help to identify high-risk patients.

Left atrial appendage closure in patients with or without previous embolic stroke/TIA. Data from the moncentric RESET registry

Left atrial appendage (LAA) closure (LAAC) is indicated in patients with non valvular atrial fibrillation (AF) and contraindication to oral anticoagulation (OAC). Since December 2013, patients referred for LAAC have been included in a prospective registry and have given an informed consent for a five-year follow-up (FU). We compare charca and mid term follow up of those with (group S) and without (group NS) history of embolic stroke/TIA. Contra indication to OAC was established by a multidisciplinary team. Feasibility of LAAC was assessed by Cardiac Computed Tomography angiography. A 45 days TEE was planned. Thereafter patients received a phone call every 6 months. Available data were analyzed in case of adverse event. From 100 patients implanted, 29 had history of stroke. Demographics were not significantly different in both groups in term of age (77.1 ± 7.6 vs. 78 ± 7.2 yrs), sex (62% vs. 72% male), AF type (permanent in 55% vs. 49%), congestive heart failure (31% vs. 39%) and HAS BLED score (4.4 ± 1 in both). Obviously CHA2DS2VASc score was higher in S group (5.8 ± 1.4 vs. 4.2 ± 1.2%). LAA morphology was not different in both groups with a majority of Windsock type (59% vs. 55%), and a tendency of more Cactus type (17% vs. 5%) and less Chicken Wind type (24% vs 38%) in S group. Antithombotic treatment after implantation was not different in both groups, antiplatelet (66% vs. 65%), low dose anticoagulant for 45 days (10% vs. 6%), no ATT (24% vs. 27%). At 45 days 1 patient died from refractory bronchospasm in the N-S group. One year FU was obtained in 16 and 44 patients in group S and NS. No fatal or non-fatal embolic event occurred. A tendency of less death was noted in S-Group (6.3% vs. 29.5%). TEE was performed in 17 and 39 cases and a thrombus was detected in 2/17 (11.8%) patients in S group and 1/39 (2.6%) in N-S group. Patients with a history of previous stoke/TIA seem to have similar characteristics and prognosis than those without.