Atrial Appendage Thrombus Research Articles

Incidental Finding of a Right Atrial Appendage Thrombus in a Patient With Dilated Cardiomyopathy and Diffuse B-cell Lymphoma

Incidental Finding of a Right Atrial Appendage Thrombus in a Patient With Dilated Cardiomyopathy and Diffuse B-cell Lymphoma

Diagnostic Accuracy of Left Atrial/Left Atrial Appendage Thrombus in Patients with Atrial Fibrillation: A Systematic Review and Network Meta-Analysis.

This paper aimed to appraise the diagnostic precision of assorted methodologies to identify left atrial/left atrial appendage (LA/LAA) thrombus through a network meta-assessment. Methodologically, we conducted a comprehensive literature search across multiple databases. Utilizing the risk of bias tool from the Cochrane Collaboration, methodological quality of included studies was critically assessed and potential publication bias was examined via funnel plots. The subsequent data analysis was executed using Stata software, with the most efficacious diagnostic modalities being determined based on cumulative ranking curve (SUCRA) values. We scrutinized a sum of 18 papers, comprising 4102 subjects and utilizing 10 different diagnostic techniques. The hierarchical results derived from the network meta-analysis indicated that in regards to sensitivity, the dual-source cardiac computed tomography (DSCT) was superior (with a SUCRA value of 71.7%), it was succeeded by 3-minute delayed cardiac computed tomography (CCT) (scoring 66.8%), which surpassed the transesophageal echocardiography (TEE) (holding a SUCRA value of 57.5%). In terms of specificity, DSCT was the best (SUCRA value of 84.3%), followed by three dimensional (3D) cardiac magnetic resonance imaging (3D-CMRI) (SUCRA value of 78.0%), which was better than TEE (SUCRA value of 66.6%). In terms of positive likelihood ratio (PLR), 6-minute delayed CCT (SUCRA value of 85.6%) was superior to 3-minute delayed CCT (SUCRA value of 80.1%), both of which were superior to TEE (SUCRA value of 69.1%). DSCT (SUCRA value of 89.3%) had the best negative likelihood ratio (NLR), while DSCT (SUCRA value of 79.9%) had the highest accuracy. This study demonstrated that DSCT outperformed TEE in sensitivity, specificity, NLR, and accuracy in identifying thrombus of LA/LAA among patients suffering from atrial fibrillation. Our conclusion is that DSCT is the best in diagnosing LA/LAA. In addition, 3D-CMRI and 3-minute delayed CCT are expected to replace TEE.

Abstract 17083: Hunting For Clot: Strokes In Patients With Cardiac Amyloid

Case Presentation: A 76-year-old female with history of amyloid light chain (AL) cardiac amyloidosis and prior stroke presented with acute bilateral leg weakness. MRI of the brain revealed subacute infarcts in the right basal ganglia and precentral gyrus as well as chronic left cerebellar infarctions. CT angiogram of the head and neck did not show any significant intracranial or carotid artery disease. All current and previous admission ECGs and telemetry showed sinus rhythm with no atrial arrhythmias. Transthoracic echocardiogram with bubble study noted LV ejection fraction of 62%, normal left atrial size and no evidence of an intracardiac shunt. Despite the lack of traditional indicators, a cardioembolic source was feared given the high risk of intracardiac thrombi in AL amyloid patients. A TEE was performed and confirmed a large left atrial appendage (LAA) thrombus with severely reduced velocities and spontaneous echo contrast (Figure 1). The patient was started on apixaban for secondary stroke prevention. Discussion: Amyloid proteins deposit throughout heart tissue, distorting mechanical function and electric conduction resulting in reduced blood flow and a high risk of intracardiac thrombi that is 10 times that of nonamyloid patients. Patients with cardiac amyloidosis have a high prevalence of atrial arrhythmias, particularly atrial fibrillation, but remain at significant risk of thrombi even in the absence of these arrhythmias, ranging from 3-20%. Risk factors for clot include AL type amyloid and features of worsened hemodynamics such as LV systolic and diastolic dysfunction, elevated heart rates and lower systolic blood pressure. This case demonstrates the importance of aggressively “hunting” for intracardiac thrombi in amyloid patients presenting with stroke even without perceived risk factors, especially given the protective effect of starting anticoagulation.

Transesophageal echocardiography for cardiovascular risk estimation in patients with sepsis and new-onset atrial fibrillation: a multicenter prospective pilot study

BackgroundEchocardiographic parameters have been poorly investigated for estimating cardiovascular risk in patients with sepsis and new-onset atrial fibrillation. We aim to assess the prevalence of transesophageal echocardiographic abnormalities and their relationship with cardiovascular events in mechanically ventilated patients with sepsis and new-onset atrial fibrillation.MethodsIn this prospective multicenter pilot study, left atrial/left atrial appendage (LA/LAA) dysfunction, severe aortic atheroma, and left ventricular systolic dysfunction were assessed using an initial transesophageal echocardiographic study, which was repeated after 48–72 h to detect LA/LAA thrombus formation. The study outcome was a composite of cardiovascular events at day 28, including arterial thromboembolic events (ischemic stroke, non-cerebrovascular arterial thromboembolism, LA/LAA thrombus), major bleeding, and all-cause death.ResultsThe study population comprised 94 patients (septic shock 63%; 35% women; median age 69 years). LA/LAA dysfunction, severe aortic atheroma, and left ventricular systolic dysfunction were detected in 17 (19%), 22 (24%), and 27 (29%) patients, respectively. At day 28, the incidence of cardiovascular events was 46% (95% confidence interval [CI]: 35 to 56). Arterial thromboembolic events and major bleeding occurred in 7 (7%) patients (5 ischemic strokes, 1 non-cerebrovascular arterial thromboembolism, 2 left atrial appendage thrombi) and 18 (19%) patients, respectively. At day 28, 27 patients (29%) died. Septic shock (hazard ratio [HR]: 2.36; 95% CI 1.06 to 5.29) and left ventricular systolic dysfunction (HR: 2.06; 95% CI 1.05 to 4.05) were independently associated with cardiovascular events.ConclusionsTransesophageal echocardiographic abnormalities are common in mechanically ventilated patients with sepsis and new-onset atrial fibrillation, but only left ventricular systolic dysfunction was associated with cardiovascular events at day 28.

Thromboembolic risk of movable type left atrial appendage thrombi in patients with atrial fibrillation under widespread use of anticoagulants

Abstract Background Left atrial appendage thrombi (LAAT), especially movable type LAAT, have been reported to be high-risk for thromboembolic events in patients with atrial fibrillation (AF). However, thromboembolic risk of the movable-type LAAT under widespread use of anticoagulant therapy remains unclear. Methods We retrospectively studied 65 LAAT patients taking anticoagulants out of 1381 consecutive patients who underwent transthoracic echocardiography prior to cardioversion or catheter ablation for AF. Patients with significant valvular disease and coagulation disorder were excluded. Clinical data were evaluated at the time of TEE. The LAAT were classified into movable and fixed type LAAT by three independent observers. Results Sixteen of 65 LAAT patients showed movable type LAAT. During follow-up (42±34 months), one patient underwent emergency thrombectomy, 5 patients developed thromboembolic event, and 12 patients died. There were no differences in clinical data, parameters, thrombectomy/thromboembolic event, and survival rate between patients with movable and fixed type LAAT. Conclusion Thromboembolic risk of the movable-type LAAT is the same as fixed type LAAT, under widespread use of anticoagulant therapy. Funding Acknowledgement Type of funding sources: None.

High level of growth differentiation factor 15 and lower left ventricular ejection fraction as predictors of left atrial thrombosis in patients with nonvalvular atrial fibrillation

Abstract Background The presence of left atrial/left atrial appendage (LA/LAA) thrombus is used as a surrogate marker of potential stroke in patients (pts) with atrial fibrillation (AF). Purpose To assess the role of growth differentiation factor 15 (GDF-15) level, clinical and echocardiographic (EchoCG) data as predictors of LA/LAA thrombus in pts with nonvalvular AF. Methods Out of 158 pts with nonvalvular AF admitted to Cardiology Center for radiofrequency ablation or elective cardioversion in 2019–2020 2 groups were formed according to transesophageal EchoCG results: group 1 included pts without LA/LAA thrombus (n=102, mean age 59.5±6.0 years) and group 2 (n=42, mean age 60.9±8.8 years) – pts with LA/LAA thrombus. Arterial hypertension was found in 93 pts of group 1 (91%) and in 40 pts of group 2 (95%, p=0.42), coronary artery disease - in 53 pts (52%) and 29 pts (69%), respectively (p=0.06). Both groups did not differ in frequency and spectrum of oral anticoagulants administration. General clinical assessment, EchoCG, and laboratory tests were performed, including GDF-15 (pg/ml) levels using Human GDF-15/MIC-1 ELISA kit and NT-proBNP (pg/ml) in blood. Results Pts with LA/LAA thrombus more often had persistent AF, while paroxysmal AF was more common in pts without thrombus. There was a tendency to more significant congestive heart failure in group 2. Mean CHA2DS2-VASc score was higher in pts with LA/LAA thrombus, also there was a tendency to a larger proportion of pts with scores ≥3. According to EchoCG data, sizes and volumes of both atria, right ventricle, end-systolic volume, left ventricular (LV) size, pulmonary artery systolic pressure and LV mass index were higher in group 2; LV ejection fraction (LVEF) was normal in both groups, but it was significantly lower in pts with LA/LAA thrombus: 59.1±5.1 and 64.0±7.3, respectively (p<0.001). GDF-15 and NT-proBNP levels were significantly higher in group 2 compared to group 1: p=0.00025 and p=0.ehab724.048801 respectively. According to ROC analysis cut-off were set at level >935.0 pg/ml for GDF-15 (AUC=0.705, 95% CI 0.609–0.800, p<0.001) and >143 pg/ml for NT-proBNP (AUC=0.759, 95% CI 0.670–0.849, p<0.001). Multivariate logistic regression revealed the following variables as independent predictors of LAAT: GDF-15 >935.0 pg/ml (OR=4.132, 95% CI 1.305–13.084) and LVEF (OR=0.859, 95% CI 0.776–0.951). According to ROC analysis, the model had a good quality: AUC=0.776 (p<0.001), sensitivity was 78.3%., specificity - 78.3%. Conclusion High level of GDF-15 (>935.0 pg/ml) along with lower LVEF are independent predictors of LA/LAA thrombus in pts with nonvalvular AF. Funding Acknowledgement Type of funding sources: None.

Assessing the left atrial appendage thrombus using 3D transesophageal echocardiography and pulse wave doppler

Abstract Background/Introduction In some patients, detecting and visualizing left atrial appendage (LAA) thrombus (especially at fundus level) seems to be challenging. Thus looking for indirect signs such as morphology, size and function may be of use. Purpose Finding echocardiographic signs suggesting presence of LAA thrombus using 3D TEE & pulse wave doppler. Methods We collected data via transesophageal echocardiography (TEE) from different set of patients with diseased heart (valvular especially mitral stenosis, congenital, pre-cardiac conversion for atrial fibrillation). And that by using EPIQ7 echo machine by Phillips. With each patient, we acquired pulse wave doppler determining the maximum (telesystolic) emptying velocity at mid LAA (MEV-LAA), and maximum long axis surface area of LAA (LAA-SA) using Xplan modality or multiplanar reconstruction from gated 3D acquisitions of LAA. Doing so we tried to assess the relationship between LAA thrombus and its morphology (2D/3D) using the 04 shapes classification (windsock, cauliflower, chicken wing, cactus), measuring LAA-SA considering a cutoff of 6cm2 or above a dilated LAA. A MEV-LAA considered diminished if less than 25cm/s. Finally we calculated the ratio of LAA-SA/MEV-LAA. Results We assessed a group of 55 patients. LAA thrombus was visualized in 10 of them. The predominant morphology was windsock 50.9% then equally chicken wing and cauliflower 14.5%, cactus 11%. Thrombus occurred in major part with cauliflower type with 50% of all patients with the same shape. LAA was dilated in 25 patients in whom 7 had LAA thrombus (Se: 70% Sp: 60% PPV: 22%). LAA maximum emptying velocity was reduced in 18 patients in whom 10 had LAA thrombus (Se: 100% Sp: 82.2% PPV: 36%). We found that 7 patients with a ratio LAA-SA/MEV-LAA <1.7 had LAA thrombus (Se: 70% Sp: 97.8% PPV: 47%). Cauliflower morphology has the highest occurrence of thrombus as demonstrated in the literature. LAA-SA is the least reliable criteria associated with LAA thrombus. MEV-LAA is has the most sensible value of the three measurements. The ratio LAA-SA/MEV-LAA seems to have the highest specificity and positive predictive value in terms of association with thrombus (in cauliflower type this ratio seems to be less specific). Some limitations of this study was the limited number of patients assessed, no comparison in terms of sex (LAA size is different in men and women according to literature), sinus rhythm versus atrial fibrillation (LAA maximum emptying velocity), no correlation with CT-scan of LAA concerning dimensions and thrombus. Conclusion 3D transesophageal echocardiography and pulse wave doppler study of the LAA seems to be associated with thrombus formation especially indirect signs and indexed values (ratio LAA-SA/MEV-LAA), that tends to push the diagnostic power of TEE. Promptly this will lead to more investigations on a large scale number of patients in different sub-type groups. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Mustapha Pacha University Hospital Center, department of Cardiology A2 3D TEE of LAA and Mitral prosthesisXplan on LAA, cauliflower type

Serum heparanase levels and left atrial/left atrial appendage thrombus in patients with nonvalvular atrial fibrillation.

Data regarding the possible role of heparanase (HPA) in the occurrence of left atrial/left atrial appendage (LA/LAA) thrombus in patients with atrial fibrillation (AF) is lacking. The goal of the present study was to assess the association between plasma levels of HPA and LA/LAA thrombus in AF. A total of 687patients with nonvalvular AF (NVAF) without anticoagulation therapy were included from January 2016 to June 2019. Serum HPA analysis was performed with acommercially available human ELISA kit. Logistic regression models were used to test for association. Serum HPA levels were significantly higher in patients with LA/LAA thrombus than in those without LA/LAA thrombus (270.8 [193.4 ± 353.2] pg/mL vs 150.3 [125.2 ± 208.4] pg/mL; P < 0.001). In multivariate analysis, serum HPA remained asignificantly independent predictor of LA/LAA thrombus (odds ratio 1.674, 95% confidence interval [CI] 1.339-2.289, P < 0.001). In the receiver operating characteristic (ROC) curve analysis, HPA showed apredictive value with an area under the curve (AUC) of 0.757 (95% CI 0.652-0.810, P < 0.001). The optimal cutoff level for HPA predicting LA/LAA thrombus was 210.7 pg/mL, with asensitivity of 74.3% and aspecificity of 64.8%. An elevated HPA level was associated with the presence of LA/LAA thrombus in patients with AF. HPA might portend the risk for the prothrombotic state in AF patients.

Comparative study of cardiac magnetic resonance imaging and transesophageal echocardiography in detection of left atrial and left atrial appendage thrombi

Abstract Funding Acknowledgements Type of funding sources: None. Background Left atrial (LA) thrombi are the most common intracardiac masses. Left atrial appendage (LAA) is the most common site for thrombus formation in patients with atrial fibrillation (AF), and in patients with valvular lesions. Transesophageal echocardiography (TEE) has been the conventional investigation for thrombus detection. However, because TEE is a semi-invasive technique; a completely non-invasive technique would be of great concern. Purpose The aim of this study is to evaluate the feasibility and diagnostic performance of cardiac magnetic resonance imaging (CMR), for the assessment of thrombi in the left atrium and left atrial appendage (LA/ LAA). Also whether CMR is comparable to TEE in identification and measurement of thrombus size. Methods We studied 43 patients who were diagnosed to have LA/LAA thrombus, or highly suspected thrombus by TEE. They underwent multisequence CMR for assessment of thrombus detection; within 7 days of TEE performance. Data collected from CMR study were statistically analyzed to evaluate for sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and overall accuracy of detection of LA/LAA thrombus using TEE as the gold standard. Also agreement between both imaging techniques was assessed using kappa agreement coefficient. We conducted a questionnaire where 10 questions were asked to every patient in the study. It aimed to obtain an idea about patients’ opinion of both tests. Results During the study period of 13 months, 43 patients were assessed. Twenty one patients had AF and 22 patients were in sinus rhythm. The median CHA2DS2VASc score of AF patients was 2.52 ± 1.12, and 76.7% of patients were undergoing anticoagulation therapy. In all subjects, the LAA was readily visualized with CMR. When evaluating the diagnostic performance of CMR results revealed overall sensitivity, specificity, PPV, NPV and accuracy of 97.44%, 75%, 97.44%, 75% and 95.35% respectively. Results of questionnaire was statistically significant p value yielding good overall opinion for the sake of CMR. There was an additional role for CMR regarding tissue characterization; where CMR detected 3 cases, diagnosed by TEE as thrombus, 1 case revealed Libman-Sacks Endocarditis and 2 cases revealed fibroelastoma. This made a paradigm shift in patient management. Conclusion CMR is a noninvasive, feasible and comparable modality for thrombus detection in the LA and LAA and could be a reasonable, more comfortable alternative to TEE.

ASNC/AHA/ASE/EANM/HFSA/ISA/SCMR/SNMMI Expert Consensus Recommendations for Multimodality Imaging in Cardiac Amyloidosis: Part 1 of 2-Evidence Base and Standardized Methods of Imaging.

ASNC/AHA/ASE/EANM/HFSA/ISA/SCMR/SNMMI Expert Consensus Recommendations for Multimodality Imaging in Cardiac Amyloidosis: Part 1 of 2-Evidence Base and Standardized Methods of Imaging.

Left atrial appendage closure in the presence of thrombus: incidence, technique and outcomes

Abstract Funding Acknowledgements Type of funding sources: None. Background Patients with left atrial appendage (LAA) thrombus are excluded for LAA occlusion (LAAO) in clinical trials. However, some of them may require this therapy due to repeated thromboembolisms despite accurate anticoagulation. Aim The aim of the study is to describe the prevalence of LAA thrombosis in patients submitted for LAAO in a high-volume center of LAAO procedures, explaining the employed technique and results in this scenario. Methods Single-center retrospective analysis including all consecutive patients referred for LAAO. Results LAA thrombus was detected by TEE in 8/76 patients referred for LAAO (10.5%). Five of them underwent LAAO despite the presence of thrombus due to clinical conditions. All the procedures were successfully performed with Amulet devices (Table). The following preventive measures were putting in place during the implants: avoidance of contrast injection into the LAA during the procedure (non-touch technique), TEE measure for device size election; and TEE device deployment guidance with special care to the the sheath orientation and depth enabling a slow and single implant of the device partially released in the LAA before complete implantation at the entrance of the LAA (Figure. A&amp;B: Large LAA thrombus partially occupying the landing zone. C: Thrombus sealed by LAAO device. D&amp;E: Non-touch technique: echo-guided progressive deployment of the LAAO device without thrombus shifting). No cerebral protection devices were used. TEE performed one month after the procedure ruled out the presence of residual thrombi or leaks in all cases. There were no events after a median follow-up of 17.1 months (range: 32.3-1.1) Conclusion LAAO in patient with LAA thrombus can be effectively and safely performed, in high-volume centers and with an accurate technique, under accurate TEE guidance. Abstract Figure. LAA thrombus and occlusion technique

Atrial thrombus detection on transoesophageal echocardiography in patients with atrial fibrillation undergoing cardioversion or catheter ablation: A pooled analysis of rates and predictors.

To summarize data on the rates and predictors of left atrial thrombus/left atrial appendage thrombus (LAT/LAAT) detection by transoesophageal echocardiography (TEE) before electrical cardioversion (ECV) or catheter ablation (CA) for atrial fibrillation (AF). EMBASE, MEDLINE, and Web of Science Core Collection were searched to identify all studies providing relevant data and published by October 7, 2020. A random-effects meta-analysis method was used to pool effect size estimates. A total of 85 studies were included, reporting data from 56 660 patients with AF. In patients undergoing CA and ECV, the pooled prevalence of LAT/LAAT was 1.8% and 7.5% in those not on oral anticoagulation (OAC), 1.8% and 5.5% in those taking OAC, and 1.3% and 4.9% in case of adequate OAC, respectively. According to the type of OAC, the prevalence was 2.0% and 7.6% for vitamin K antagonist, 1.3% and 3.5% for direct oral anticoagulant. Predictors of LAT/LAAT detection were nonparoxysmal AF (odds ratio [OR]: 3.6, 95% confidence interval: 2.4-5.2), hypertension (OR: 2.9, 1.2-7.0), previous stroke (OR: 3.0, 1.6-5.63), heart failure (OR: 4.3, 2.7-6.8), and CHADS2 score ≥2 (OR: 3.3, 1.9-5.8) for patients undergoing CA; and heart failure (OR: 2.8, 1.3-6.2) and the CHA2 DS2 -VASc score (OR: 2.55, 1.5-4.5) for those undergoing ECV. The prevalence of LAT/LAAT in AF patients undergoing ECV or CA varies widely, mainly due to differences in patient risk profiles and OAC types. Further research should determine whether the predictors of LAT/LAAT detection identified by this study could be used to select patients who require preprocedural TEE.

Abstract P105: Identification of Cardioembolic Sources and Myocardial Injury in Acute Ischemic Stroke With Delayed-Phase, Low-Dose Chest Ct by Means of a Dual-Layer Spectral Ct Scanner

Background: The COVID-19 pandemic has promoted adaptations in diagnostic algorithms. We explored the feasibility and accuracy of delayed phase (DP) chest computed tomography (CT) performed immediately after brain CT perfusion (CTP) for the identification of thrombotic complications and myocardial fibrosis among patients admitted with acute ischemic stroke (AIS). Methods: Since July, we have incorporated the use of low dose chest CT scans using a spectral CT scanner in all patients admitted with AIS, encouraging acquisitions, five min after brain CTP. All scans were non gated and comprised low dose chest CT scans, without additional contrast. Using virtual monochromatic imaging and iodine maps, we evaluated the presence of thrombotic complications, myocardial late enhancement, and myocardial extracellular volume (ECV), as a surrogate of edema and interstitial fibrosis. Results: We included 22 patients. The mean age was 66.2±19.6 years. In 5 patients, a cardioembolic (CE) source was later identified by transesophageal echocardiogram (TEE), [left atrial appendage (LAA) thrombus, n=1], transthoracic echocardiogram with agitated saline injection (patent foramen ovale n=2), or by EKG (atrial fibrillation). Seven patients further underwent either TEE or cardiac CT to identify CE sources. DP non gated chest CT had a sensitivity and specificity of 100% to identify CE sources, 1 LAA thrombus correctly detected. Chest CT identified pulmonary thromboembolism (PE), later confirmed with CT angiography. Chest CT identified myocardial late enhancement in 16 patients (80% in CE vs. 71% in non CE, p=0.68), myocardial fat in 1, and coronary calcification in 77% [with 2.6±2.2 vs 3.8±3.6 coronary calcified segments in CE vs. non CE strokes, p=0.36). The mean ECV was 35±4% in CE vs 32±6% in non CE strokes (p=0.17). The 2 patients with a positive PCR test for COVID-19 showed evidence of myocardial late iodine enhancement, and incremented ECV of the septal wall (38% and 40%, respectively). Conclusions: In this pilot study, DP, non ECG gated, low dose chest CT scan performed 5 min after brain CTP with a spectral scanner; enabled straightforward identification of CE sources among patients with AIS. This approach allowed detection of PE and myocardial injury.

Abstract 12852: Cardioembolic Myocardial Infarction in the Setting of Complex Immunologic Disease

Background: The occurrence of left atrial appendage (LAA) thrombus formation and embolic myocardial infarction (MI) is rarely reported in the absence of atrial fibrillation (AF). In patients with a history of immunologic disease, a multidisciplinary approach is critical for prompt evaluation and treatment. Presentation: A 46-year-old woman with chest pain and lower extremity paresthesias was found to have NSTEMI. Past medical history was notable for vasculitis and multiple organ infarcts. Coronary angiogram and cardiac MRI showed no obstructive or structural disease. One month later she had recurrent chest pain with inferior ST-elevations on ECG and troponin of 24ng/mL. Investigations and Outcome: Coronary catheterization showed multiple embolic occlusions (Figure 1A and 1B). Subsequent TEE showed LAA thrombus (Figure 1C). Continuous telemetry and serial ECGs from initial presentation were negative for AF. Hypercoagulable and antiphospholipid testing was negative. Brain MRI for paresthesias showed dural enhancement and subsequent biopsy found an IgG4 inflammatory process. Treatment with warfarin, corticosteroids, and rituximab was initiated. No atrial fibrillation was detected on serial EKGs and an event monitor during one year of follow-up. There was no embolic recurrence. Conclusion: Autoimmune diseases can have complex organ involvement through lesser known mechanisms which often present as diagnostic challenges. This case identifies the potential for cardioembolic events, including myocardial infarction, in IgG4 vasculitis even in the absence of atrial fibrillation or hypercoagulability.

Use of Computed Tomography Scan to Rule Out Phantom Thrombus in the Left Atrial Appendage

Occurrence of left atrial appendage (LAA) thrombus is a frequent complication of atrial fibrillation (AF) and it increase thromboembolic risk. Transesophageal echocardiography (TEE) is considered the gold standard to ensure that this chamber is thrombus free. Multidetector computed tomography (CT) scan has some advantages such the possibility to get 3D reconstruction and explore another structures in relationship with the LAA. However, lack of specificity in case of false positive images with filling defects due to slow velocities in the LAA. Methods and Results: 34 patiens with suspected thrombus by a previous CT scan or transesophageal echo were included in analisys. The aim of study was evaluated the utility of CT scan with delayed acquisition protocol to exclude LAA thrombus. In all of patients, complete LAA filling was observed, with a sensitivity, specificity and negative predictive value of 100% to differentiate circulatory stasis from thrombus. Conclusion: Perform a CT scan with a delayed acquisition protocol and in prone position are safe techniques to rule out fake thrombus.

P765 Does detection of thrombus in left atrial appendage increase risk of ischemic stroke and mortality?

Abstract Background Left atrial appendage (LAA) thrombus is one of causes of cardiogenic stroke and detection of LAA thrombus by transoesophageal echocardiography (TOE) strongly suggest cardiogenic stroke. It was reported that cardiogenic stroke patients had higher in-hospital mortality about 19%; however, little is known about LAA thrombus and mortality after indexed detection of LAA thrombus. We investigated LAA thrombus detection and their prognosis including ischemic stroke and survival. Methods The patients who were performed TOE between 2005 and 2016 in our hospital were enrolled in this study. Patients were divided into 2 groups based on thrombus detection in the LAA, and baseline characteristics and outcomes including prevalence of 5-y stroke-free and survival from the indexed TOE were compared. Results Among the 1260 study patients, the follow-up duration was median 971 d (interquartile range 345 d – 2017 d), and 67% of the patients were performing TOE for atrial fibrillation (AF), 20% for cerebral infarction, and 14% for valvular heart disease. Non-valvular AF was seen in 64% of the study patients and rheumatic AF was in 2%. The age (74 y [66 y – 79 y] vs 70 y [62 y – 76 y], p &amp;lt; 0.001), the prevalence of male sex (67% vs 69%, p = 0.63), and hemoglobin level (13.9 g/dl [12.5 – 15.1 g/dl] vs 13.8 g/dl [12.4 – 14.9 g/dl], p = 0.49) were similar between the patients with LAA thrombus and those without. The CHA2DS2-VASc score (p = 0.008), the prevalence of receiving anticoagulation before TOA (34% vs 24%, p = 0.01), those of after TOA (98% vs 66%, p &amp;lt; 0.001), serum creatinine (0.92 mg/dl [0.80 – 1.10 mg/dl] vs 0.85 mg/dl [0.71 – 1.00 mg/dl], p &amp;lt; 0.001), d-dimer level (1.7 mcg/ml [0.9 – 3.5 mcg/ml] vs 0.8 mcg/ml [0.5 – 2.2 mcg/ml], p &amp;lt; 0.001), and plasma brain natriuretic peptide (315 pg/ml [128 – 515 pg/ml] vs 126 pg/ml [47 – 284 pg/ml], p &amp;lt; 0.001) were higher in the patients with LAA thrombus than those without. The 5-y ischemic stroke-free rate was lower in the patients with LAA thrombus than those without (p &amp;lt; 0.001) (Figure, Panel A); however, the 5-y survival was similar between the 2 groups (p = 0.93) (Panel B). Conclusions The patients who were detected thrombus in the LAA had higher incidence of ischemic stroke, but the survival rate were similar. The higher rate of receiving anticoagulation therapy in the patients with LAA thrombus may be the cause of this discrepancy. Further studies are necessary to clarify this issue. Abstract P765 Figure

Cardiac MRI for detecting left atrial/left atrial appendage thrombus in patients with atrial fibrillation

The aim of this meta-analysis was to evaluate the accuracy of cardiac magnetic resonance (CMR) in detecting left atrial/left atrial appendage (LA/LAA) thrombus and to analyze the difference between the diagnostic accuracy of various imaging sequences. PubMed, Web of Science, Embase, and the Cochrane Library were systematically searched for studies from 2000 to 2017 that compared CMR with transesophageal echocardiography (TEE) in detecting LA/LAA thrombus. The CMR images were analyzed in four categories: (1)cine-CMR; (2)first-pass contrast-enhanced 3D CMR angiography (CE-MRA); (3)delayed-enhancement CMR (DE-CMR); and (4)CMR, regardless of the magnetic resonance sequences used. Descriptive and quantitative information was extracted and Meta-DiSc1.4 was used to perform the analysis. The analysis included 582 patients from seven publications. The pooled sensitivity, specificity, diagnostic odds ratio, positive likelihood ratio, negative likelihood ratio, and summary receiver operating characteristic of cine-CMR were 91.00%, 93.00%, 50.43, 10.04, 0.24, and 93.93%, respectively; for CE-MRA, the values were 77.00%, 97.00%, 179.21, 51.77, 0.30, and 97.63%, respectively; for DE-CMR, 100.00%, 99.00%, 849.70, 77.62, 0.09, and 99.38%, respectively; and for CMR, 80.00%, 99.00%, 187.54, 24.21, 0.17, and 97.71%, respectively. In patients with atrial fibrillation, CMR has been proven to be afavorable diagnostic technique for the detection and assessment of LA/LAA thrombus. Among the imaging sequences evaluated, DE-CMR had the highest sensitivity, specificity, and diagnostic accuracy.

Growth differentiation factor 15 is associated with left atrial/left atrial appendage thrombus in patients with nonvalvular atrial fibrillation.

There is evidence suggesting that growth differentiation factor 15 (GDF-15) appears to be associated with stroke in patients with atrial fibrillation (AF). AF-related thromboembolic stroke is predominantly attributed to the thrombus from the left atrium (LA) or left atrial appendage (LAA). GDF-15 is related to LA/LAA thrombus in nonvalvular AF (NVAF) patients. A total of 894 patients with NVAF without anticoagulation therapy were included in this study. All patients routinely underwent transesophageal echocardiography for detection of LA/LAA thrombus. GDF-15 was measured by enzyme-linked immunosorbent assay. Logistic regression models were used to test for association. LA/LAA thrombus was detected by transesophageal echocardiography in 69 (7.72%) patients with AF. The GDF-15 levels in the patients with LA/LAA thrombus were significantly higher than those without LA/LAA thrombus (log10 GDF-15: 2.989 ± 0.023 ng/L vs 2.831 ± 0.007 ng/L; P < 0.001). Logistic regression analysis showed that GDF-15 was an independent risk factor for LA/LAA thrombus (odds ratio [per quarter]: 1.799, 95% confidence interval: 1.381-2.344, P < 0.001) after adjusting for potential clinical risk factors. The optimal cutoff point for GDF-15 predicting LA/LAA thrombus was 809.9 ng/L (sensitivity, 75.3%; specificity, 61.5%), determined by ROC curve. The area under the curve was 0.709 (95% confidence interval: 0.644-0.770, P < 0.001). Elevated GDF-15 indicated a significantly increased risk for LA/LAA thrombus in NVAF patients. Thus, GDF-15 might be a potentially useful adjunct in discriminating LA/LAA thrombus in NVAF patients.

Mean platelet volume as a new biomarker for left atrial thrombus or thromboembolic events in nonvalvular atrial fibrillation: Weighing the evidence

Background: Mean platelet volume (MPV) is a new biomarker for left atrial appendage (LAA) thrombus or thromboembolic event with great potential. Considering its applicability and cost, it can be the chosen examination for the detection of LAA thrombus in patients with nonvalvular atrial fibrillation. This study aimed to evaluate MPV as a new biomarker for left atrial thrombus or thromboembolic events in comparison with transesophageal echocardiography. Methods: We did electronic searches on PubMed, ScienceDirect, and SpringerLink databases. Appraisal of studies was performed using critical appraisal sheets provided by the Centre for Evidence-Based Medicine. Test characteristic was extracted from the literature. Meanwhile, sensitivity, specificity, positive predictive value, and negative predictive value (NPV) were calculated based on the test characteristic. Results: Two studies met the selection criteria. Different cutoff was used in the studies (>10.5 fL and >9.4 fL) which showed significant differences in sensitivity, specificity, and positive predictive value. However, both the studies have fairly high NPV (78.95% and 72.65%, respectively). Conclusion: Currently, the best MPV cutoff value in determining the absence of thrombus in the left atrium is 10.5 fL. Although the clinical application of MPV remains limited, it can be further improved by more studies to obtain the optimal cutoff value and to increase the value of MPV by combining with other biomarkers and clinical prediction tools.

Double trouble – a case of atrial fibrillation and pulmonary embolism

Right atrial appendage thrombus is a rare complication of atrial fibrillation that can also lead to cardioembolic pulmonary embolism.