Echo Contrast Research Articles

CHA2DS2-VASc Score as a Predictor for Left Atrial Thrombus or Spontaneous Echo Contrast in Patients with Nonvalvular Atrial Fibrillation: A Meta-Analysis

Objective This meta-analysis aimed at exploring the predictive value of CHA2DS2-VASc score for the left atrial thrombus (LAT) or left atrial spontaneous echo contrast (LASEC) in patients with nonvalvular atrial fibrillation (NVAF). Methods PubMed, Embase, Web of Science, ScienceDirect, Cochrane Library, and Chinese core journals of the CNKI and Wanfang databases were searched to identify all the relevant papers that were published up to January 2020. The data were extracted for pooled odds ratios (ORs) with 95% confidence intervals (CIs), heterogeneity, subgroup, publication bias, and sensitivity analysis. Results Overall, 15 studies containing 6223 patients with NVAF were enrolled. All studies were evaluated for LAT, and 12 studies were evaluated for LASEC. The pooled analysis using a random-effects model showed that a high CHA2DS2-VASc score was related with LAT/LASEC (pooled OR = 1.59, 95% CI: 1.35–1.88, P < 0.001) with high heterogeneity (I2 = 76.9%, P < 0.001) and LAT (pooled OR = 1.83, 95% CI: 1.44–2.33, P < 0.001) with high heterogeneity (I2 = 79.4%, P < 0.001). The subgroup analysis demonstrated that the sample size may be the main source of heterogeneity. Although the Begg's funnel plot based on 15 studies for LAT/LASEC (P = 0.029) and 12 studies for LAT (P = 0.046) indicated the presence of publication bias among the included studies, the trim-and-fill method verified the stability of the pooled outcomes. In addition, sensitivity analysis indicated that all effects were stable. Conclusion The results of this meta-analysis showed that the CHA2DS2-VASc score is related with LAT and LASEC in patients with NVAF. However, more studies are warranted to address this issue.

Biomarkers for Predicting Left Atrial or Left Atrial Appendage Thrombus in Anticoagulated Patients with Nonvalvular Atrial Fibrillation.

Purpose Although atrial fibrillation (AF) is often associated with thromboembolic complications, there is no definite biomarker for detecting the presence of thrombi in the left atrial (LA) or left atrial appendage (LAA) in patients with nonvalvular atrial fibrillation (NVAF). Methods NVAF patients who underwent transesophageal echocardiography (TEE) to evaluate LA/LAA thrombus and spontaneous echo contrast (SEC) before AF ablation were included. Multivariate logistic regression and receiver operating characteristic curve (ROC) analyses were performed to explore the independent risk factors of LA/LAA thrombus and indicate the best cutoff point. Results Of the 260 consecutive subjects (mean age: 63.67 ± 9.39 years; 42% women), 45 (17.3%) patients were with LA/LAA thrombus, 131 (50.4%) were with SEC, and 84 (32.3%) were with neither thrombus nor SEC. The results of multivariate logistic regression analysis showed that N-terminal pro-B-type natriuretic peptide (NT-proBNP) (OR, 2.179; 95% CI: 1.191–3.987; p=0.012) and red cell distribution width (RDW) (OR, 2.398; 95% CI: 1.075–5.349; p=0.033) were independently correlated with the presence of LA/LAA thrombus but not D-dimer (OR, 0.999; 95% CI: 0.998–1.000; p=0.210). When all patients were divided into four groups based on the combination between RDW (cutoff value: 12.95%) and NT-proBNP levels (cutoff value: 368.9 ng/L), the rate of LA/LAA thrombus was the highest in the high RDW and NT-proBNP group. Conclusion In anticoagulation patients with NVAF, elevated NT-proBNP and RDW are related to LA/LAA thrombus. Therefore, these might be considered as useful prognostic markers in the management and treatment of NVAF patients.

Consensus recommendations for a dynamic susceptibility contrast MRI protocol for use in high-grade gliomas.

Despite the widespread clinical use of dynamic susceptibility contrast (DSC) MRI, DSC-MRI methodology has not been standardized, hindering its utilization for response assessment in multicenter trials. Recently, the DSC-MRI Standardization Subcommittee of the Jumpstarting Brain Tumor Drug Development Coalition issued an updated consensus DSC-MRI protocol compatible with the standardized brain tumor imaging protocol (BTIP) for high-grade gliomas that is increasingly used in the clinical setting and is the default MRI protocol for the National Clinical Trials Network. After reviewing the basis for controversy over DSC-MRI protocols, this paper provides evidence-based best practices for clinical DSC-MRI as determined by the Committee, including pulse sequence (gradient echo vs spin echo), BTIP-compliant contrast agent dosing (preload and bolus), flip angle (FA), echo time (TE), and post-processing leakage correction. In summary, full-dose preload, full-dose bolus dosing using intermediate (60°) FA and field strength-dependent TE (40-50 ms at 1.5 T, 20-35 ms at 3 T) provides overall best accuracy and precision for cerebral blood volume estimates. When single-dose contrast agent usage is desired, no-preload, full-dose bolus dosing using low FA (30°) and field strength-dependent TE provides excellent performance, with reduced contrast agent usage and elimination of potential systematic errors introduced by variations in preload dose and incubation time.

Assessment of Left Atrium Appendage Morphology By 3d Transesophageal Echocardiography and Its Relation to Spontaneous Echo Contrast &amp; Thrombus Formation

Assessment of Left Atrium Appendage Morphology By 3d Transesophageal Echocardiography and Its Relation to Spontaneous Echo Contrast &amp; Thrombus Formation

A new risk model for the evaluation of the thromboembolic milieu in patients with atrial fibrillation: the PALSE score.

The evaluation of thromboembolic risk is the cornerstone of atrial fibrillation (AF) management. Thromboembolic risk is associated with the presence of left atrial (LA) thrombus and spontaneous echo contrast (SEC), namely the thromboembolic milieu. We aimed to assess the predictors of the thromboembolic milieu in terms of LA thrombus and/ or SEC in patients with paroxysmal AF undergoing electrical cardioversion or catheter ablation, and to develop an effective risk model for detecting the thromboembolic milieu. We included a total of 434 patients with nonvalvular paroxysmal AF who underwent transesophageal echocardiography prior to cardioversion or catheter ablation. In patients with the thromboembolic milieu, total protein and C‑reactive protein levels, LA diameter, and systolic pulmonary artery pressure (SPAP) were higher, while left ventricular ejection fraction (LVEF) was lower than in patients without the thromboembolic milieu. In a multivariate logistic regression analysis, age, total protein levels, LVEF, LA diameter, and SPAP were independent predictors of LA thrombus and/or SEC. In a receiver operating characteristic curve analysis, the optimal cutoff values for the discrimination of patients with the thromboembolic milieu were as follows: 60 years for age; 7.3 mg/dl for total protein; 40% for LVEF; 40 mm for LA diameter; and 35 mm Hg for SPAP. Based on these cutoff values, we developed a novel risk model, namely, the PALSE score. The area under the curve for the PALSE score was 0.833. Patients with a PALSE score lower than 1 did not show thrombus or spontaneous echo contrast. The PALSE score, which includes total protein levels, age, LA diameter, SPAP, and LVEF, seemed to accurately predict the presence of the thromboembolic milieu in patients with paroxysmal AF.

Mobile mural thrombus and spontaneous echo contrast in ascending aorta after postoperative adjuvant cisplatin-based chemotherapy.

A 70-year-old asymptomatic male who had undergone a right nephrectomy for renal pelvic cancer was referred to us with a thrombus in the ascending aorta detected by contrast-enhanced computed tomography after chemotherapy with gemcitabine/cisplatin. Transesophageal echocardiography revealed a 4-cm mobile mural thrombus in the ascending aorta. An emergency thoracotomy for planned aortic root replacement was performed, but the intraoperative epi-aortic ultrasound indicated that the thrombus had disappeared, and it showed prominent spontaneous-echo contrast (SEC) in the ascending aorta. We speculate that vascular endothelium damage due to the cisplatin-based chemotherapy induced the thrombus and SEC in the ascending aorta.

Management of periprocedural anticoagulant therapy: a novel individualized approach-a transeusophageal echocardiographic study.

Patients with non-valvular atrial fibrillation who are under chronic oral anticoagulant therapy (OAC) treatment frequently require interruption of OAC treatment. By examining the presence of left atrial/left atrial appendage (LA/LAA) thrombus or dense spontaneous echo contrast (SEC) with transesophageal echocardiography (TEE) we aimed to develop an individualized strategy. To test the validity of CHA2DS2VASc score based recommendations was our secondary purpose. In this prospective study patients with non-valvular atrial fibrillation on OAC therapy were included. Patients' baseline characteristics, CHA2DS2VASc and HASBLED scores, medications, type of invasive procedures and clinical events were recorded.Each patient underwent to TEE examination prior to the invasive procedure. Bridging anticoagulation was recommended only to patients with LA/LAA thrombus. We included 155 patients and mean CHA2DS2VASc score of the study population was 3.4 ± 1.4. Seventy-one of them had LA/LAA thrombi or SEC on TEE examination and bridging anticoagulation was applied. OAC treatment was not bridged in 8 of 11 patients with prior cerebrovascular accident and 17 of 31 patients with CHA2DS2VASc score of > 4. 57 of 124 patients with CHA2DS2VASc score of ≤ 4 required bridging anticoagulation. There were 14 major bleedings decided according to ISTH bleeding classification. Major bleeding was observed only in patients underwent to high-risk bleeding procedure. In conclusion CHA2DS2VASc score by itself is not enough for decision-making regarding ischemic risk. Furthermore, since major bleedings occurred only in patients underwent to high-risk bleeding surgery, TEE-based individualisation may be a feasible approach particularly for those with high thromboembolic risk undergoing high-bleeding risk procedure.

Low vitamin D levels predict left atrial thrombus in nonvalvular atrial fibrillation

Background and aimsWe determined the association between left atrial (LA) thrombus occurrence and a non-classic risk marker, plasma levels of vitamin D, in atrial fibrillation (AF) patients on continuous non-vitamin K antagonist oral anticoagulant (NOAC) therapy for ≥4 weeks. Low levels of plasma 25-hydroxy vitamin D (25-OHD) are predictive of fatal stroke. Vitamin D has anticoagulant effects on the coagulation cascade, which are indirectly targeted by NOAC therapy. The impact of plasma levels of vitamin D on the rate of LA thrombus detected by transesophageal echocardiography (TEE) in AF patients is unknown. Methods and resultsWe enrolled 201 (133 female) AF patients who were using continuous NOAC therapy for ≥4 weeks. All patients underwent transthoracic and TEE examination. Serum concentrations of 25-OHD, C-reactive protein (CRP) levels, CHA2DS2-VASc scores and parameters, LA size, and left ventricle ejection fraction (LVEF) were examined before the TEE procedure. LA thrombus occurrence was independently associated with serum levels of 25-OHD (OR: 0.884; 95% CI: 0.839–0.932; P < 0.001), LA diameter (OR: 1.120; 95% CI: 1.038–1.209; P = 0.003), and LVEF(OR: 0.944; 95% CI: 0.896–0.995; P = 0.032). Dense spontaneous echo contrast (SEC) presence was also inversely associated with 25-OHD concentrations. ConclusionsLow 25-OHD levels, as a non-classic risk factor, were independently and significantly associated with dense SEC and LA thrombus occurrence in AF patients under NOAC therapy, as well as LA enlargement and decreased LVEF. Further large-scale studies are needed to explain the role of vitamin D deficiency, or efficacy of replacement, on LA thrombus occurrence.

A novel scoring system for stroke risk stratification in Japanese patients with low CHADS2 scores: Study using a transesophageal-echocardiogram endpoint.

BackgroundCatheter ablation is an effective treatment for atrial fibrillation (AF), but it carries risk of perioperative thromboembolism even in cases with low CHADS2 scores. Here, we examined whether a combination of clinical variables can predict stroke risk factors that are assessed by transesophageal echocardiography (TEE).MethodsThe study population consisted of 209 consecutive AF patients with a CHADS2 score of 0 or 1 (58.7 ± 10.6 years old; persistent AF, 33.0%). All patients underwent TEE, and TEE‐determined stroke risk (TEE risk) was defined as cardiac thrombus/sludge, dense spontaneous echo contrast (SEC), and/or peak left atrial appendage (LAA) flow velocity <0.25 m/s.ResultsTransesophageal echocardiography risk was observed in 10.5% of the patients. In multivariate logistic analysis, persistent AF [odds ratio (OR): 11.5, CI: 3.14‐42.1, P = .0002], left atrial diameter (LAD) (OR: 1.10, CI: 1.01‐1.20, P = .0293), contrast medium defect (CMD) in the LAA detected by computed tomography (OR: 20.2, CI: 6.3‐65.0, P < .0001), and serum brain natriuretic peptide (BNP) level (OR: 1.00, CI: 1.00‐1.01, P = .0056) were independent predictors of TEE risk. A new scoring system comprising LAD > 41 mm (1 point), BNP > 47 pg/mL (1 point), CMD (2 points), and persistent AF (2 points) was constructed and defined as TEE‐risk score. The area under the curve (AUC) for prediction of TEE risk was 0.631 in modified CHADS2 score and it was 0.852 in TEE‐risk score.ConclusionTransesophageal echocardiography risk is predictable by TEE‐risk score, and its combination with CHADS2 score may improve the stroke risk stratification in AF patients with a low CHADS2 score.

Left atrial enlargement and non-paroxysmal atrial fibrillation as risk factors for left atrial thrombus/spontaneous Echo contrast in patients with atrial fibrillation and low CHA2DS2-VASc score.

ObjectiveTo determine the risk factors for thromboembolism in lower risk patients with non-valvular atrial fibrillation (AF) and low CHA2DS2-VASc scores, which remain undefined.MethodsWe retrospectively analyzed the baseline clinical characteristics, routine laboratory parameters, and echocardiographic measurements of 705 patients (71.1% male; mean age: 52.10 ± 9.64 years) with low CHA2DS2-VASc score (0 or 1; 1 point for female sex) out of 1346 consecutive patients with non-valvular AF who underwent transesophageal echocardiography (TEE) at Guangdong Cardiovascular Institute between January 2013 and December 2015.ResultsPatients with left atrial thrombus (LAT) or spontaneous echo contrast (SEC) on TEE (24/705, 4%) showed a higher incidence rate of vascular disease (54.2% vs. 32.9%, P = 0.045) and non-paroxysmal AF (79.2% vs. 29.4%, P < 0.001), larger left atrial diameter (43.08 ± 4.59 vs. 36.02 ± 5.53 mm, P < 0.001), and lower left ventricular ejection fraction (58.23 ± 8.82% vs. 64.15 ± 7.14%, P < 0.001) than those without. Multivariate logistic regression analysis identified left atrial diameter [odds ratio (OR) = 1.171, 95% confidence interval (CI): 1.084–1.265, P < 0.001] and non-paroxysmal AF (OR = 3.766, 95% CI: 1.282–11.061, P = 0.016) as independent risk factors for LAT/SEC. In ROC curve analysis, a left atrial dimeter cutoff of 37.5 mm yielded 95.0% sensitivity and 62.7% specificity (AUC: 0.847, P < 0.0001, 95% CI: 0.793–0.914).ConclusionIn patients with non-valvular AF with low CHA2DS2-VASc score, the presence of LAT or SEC was associated with left atrial enlargement, which had moderate predictive value, and non-paroxysmal AF.

Implication of d-dimer in rheumatic severe mitral stenosis – A tertiary centre study

BackgroundIn rheumatic mitral stenosis (MS), left atrial (LA) thrombus and LA spontaneous echo contrast (LA SEC) reflect hypercoagulability. The study focuses on whether D-dimer levels predict the existence of LA thrombus and SEC in patients with severe MS. Methods95 consecutive patients with severe MS referred for transesophageal echocardiogram (TEE) between July 2011 and March 2012 to evaluate LA thrombus prior to balloon mitral valvotomy (BMV) were included in the study. D-Dimer levels in these patients were observed. ResultsOut of the 95 patients, 15 (15.8%) had LA thrombus and 52 patients had LA SEC (54.7%). Any correlation between D-Dimer levels and existence (or non-existence) of LA thrombus was not noticed from the receiver operating characteristics (ROC) curve with an area of .535. For patients with LA SEC, the D-Dimer levels were found to be considerably higher (776 ± 866 μg/L vs. 294 ± 331 μg/L, p = .001). An ideal cut-off level of 393 μg/L for diagnosing LA SEC was illustrated by the ROC curve with a sensitivity of 63.4%, specificity of 83.72%, positive predictive value of 82.5% and a negative predictive value of 65.45%. ConclusionsD-dimer levels were not representative of the presence or absence of LA thrombus in patients with severe MS. Nonetheless, this study demonstrated the substantial link between D-Dimer level and LA SEC. If a D-Dimer level of 400 μg/L or higher is taken as positive, it has high specificity and positive predictive value for diagnosing LA SEC.

P243 A rare association of isolated persistent left superior vena cava(PLSVC) with anomalous right coronary artery (RCA) in a symptomatic patient. Role of saline contrast echo (SCE) with multimodal imaging

Abstract Funding Acknowledgements Nil Introduction PLSVC with absent right superior vena cava (RSVC) is an extremely rare venous anomaly. Most of the patients with this anomaly have other associated cardiac anomalies. However, presence of an anomalous RCA has not been one of these anomalies. Case report A 36-year-old Asian healthy female with no significant medical history presented with over 3 years symptoms of chest heaviness and shortness of breath on walking two blocks. Examination was unremarkable. 2D echocardiogram revealed a 36mm dilated coronary sinus (CS), grade II tricuspid regurgitation (TR) with estimated right ventricular systolic pressure (RVSP) of 40 mmhg. Normal right and left side of the heart. SCE using 50:50 agitated saline and Gelofusine injected intravenously through the left arm showed opacification of the dilated CS first before opacifying the right atrium (RA). Right arm injection depicted the same pattern of contrast opacification which denotes presence of PLSVC with congenital absence of RSVC. No detected intracardiac shunts by SCE. No partial anomalous pulmonary venous connection (PAPVC). However, findings did not justify patient’s symptoms. Seven days loop recorder ruled out any arrhythmias that might be associated with isolated PLSVC. An exercise stress ECG was equivocal with chest discomfort but no ECG changes. We opted for CT coronary angiography (CTCA) to rule out obstructive coronary artery disease (CAD). CTCA confirmed our diagnosis of isolated PLSVC with absence of RSVC with huge CS. In addition, there was an anomalous origin of RCA from sinotubular junction above the commissure between left and right aortic CS and not from LM CS proper, taking a malignant interarterial course of a slit origin RCA with first part of it showing intramural course within the aortic wall. In view of symptoms we as a heart team explained the present risk of sudden cardiac death and possible indication for corrective surgery. A month later patient again presented with chest discomfort. We decided to do Coronary angiography to delineate actual size and dominance of RCA. RCA was a non-dominant small 1.75 mm vessel. There was a left anterior descending artery myocardial bridge. We started a beta blocker (BB) for the patient after which her symptoms improved. Patient followed up for two years later with no symptoms. We attributed her chest pain to the myocardial bridge since she improved on BB. We found there was no solid role for surgery in view of a very small non dominant RCA with no further chest pain. Conclusions Isolated PLSVC is a very rare condition. It is usually asymptomatic. But since our patient had symptoms, a search for another diagnosis was convenient. A dilated CS should always alert us to search for PLSVC. SCE is a simple, inexpensive and reproducible diagnostic tool that might help in solving a challenging diagnosis. Multimodal imaging has a leading role in both proper diagnosis and in management of this condition Abstract P243 Figure. Anomls. RCA - PLSVC to CS -Contrast echo

Study of Left Atrial Appendage Function in Patients of Severe Rheumatic Mitral Stenosis and Effect of Successful PTMC on SEC Grading

Background: Left Atrial Appendage (LAA) dysfunction is common in patients of Mitral stenosis (MS). In the present study we compared the LAA function amongst patients of severe rheumatic MS with particular reference to spontaneous echo contrast (SEC) and evaluated the effect of successful Percutaneous Transvenous Mitral Commissurotomy (PTMC) on SEC grading. Methods: It was a single centre prospective descriptive type of study. Total 75 cases were included during the study period from 2016 to 2020. Symptomatic patients with severe rheumatic mitral stenosis (MVA<1.5cm2) in sinus rhythm fulfilling the elective PTMC intervention criteria and those who had a successful intervention only were included. All the patients underwent Clinical examination, ECG, detailed TTE and TEE before, Immediately after (within 24hrs) & after 6 months of PTMC. Results: In the present study mean LAAAC% and LAA PW Doppler velocities were significantly less in patients of severe rheumatic Mitral Stenosis having SEC than patients without SEC, implying more severe LAA dysfunction in patients with SEC. LAA Tissue Doppler velocities were also less in patients with SEC compared to patients without SEC but it was statistically not significant. There was a significant negative correlation between SEC grading and LAAAC (%) and LAA PW Doppler velocities (LAAEDE Velocity, LAALDE Velocity and LAAF velocity), i.e. greater the degree of SEC lesser was the LAAAC (%), LAAEDE Velocity, LAALDE Velocity and LAAF velocity, suggesting more severe LAA dysfunction in patients with greater degree of SEC. There was also negative correlation between SEC grading and LAA Tissue Doppler velocities (ELAA Velocity, ALAA Velocity, SLAA Velocity) but it was statistically not significant. Successful PTMC resulted in significant decrease in SEC grading. Conclusion: Among the patients of severe rheumatic mitral stenosis, presence of SEC implies severe LAA dysfunction, greater the intensity of SEC, greater would be the severity of LAA dysfunction and successful PTMC results in improvement of SEC grading.

P242 When there is no time for further imaging

Abstract Introduction Cardiac tamponade (CT) is a clinical syndrome characterized by hemodynamic abnormalities resulting from an increase in pericardial pressure due to accumulation of fluid. Tamponade is one of the cardiac emergencies where urgent management steps are crucial and life saving. Absolute goal of treatment in Cardiac tamponade is to relieve the intra-pericardial pressure and to reverse the hemodynamic shutdown, by removal of the pericardial fluid via pericardiocentesis or surgical drainage. As much inevitable as it is, pericardiocentesis is relatively contraindicated when the effusion is associated with aortic dissection or myocardial rupture due to the potential risk of aggravating the dissection or rupture via rapid pericardial decompression and restoration of systemic arterial pressure. Case description A 44-year-Old transit passenger was admitted after she developed sudden onset of palpitations, vomiting and epigastric pain. She was in sinus tachycardia when brought to the Emergency department, within minutes’ patient went into cardiac shock with severe metabolic acidosis. She was admitted to ICU and subsequently intubated. Chest X-ray showed evidence of Pleural effusion with enlarged cardiac shadow, which prompted an urgent transthoracic echocardiogram. Echo findings were consistent with clinical cardiac tamponade with a large left pericardial mass compressing the lateral LV wall and aortic root, with a color flow from the mass toward the left coronary system. Mean while the patient was rapidly deteriorating, with and patient was not stable to undergo further imaging (CT or MRI), urgent contrast echo was done to rule out vascular connection between the mass and pericardial fluid, The Echo contrast study showed no vascular connection from the mass to the pericardial space ,however there was a connection from the mass to the left coronary system as shown in the figure, based on these findings a pericardial drainage was done successfully. These findings were confirmed by contrast CT scan after patient is stabilized. Patient gradually improved clinically, was extubated successfully, the provisional diagnosis was suspicious of pheochromocytoma,however the final diagnosis not established as the patient travelled to home country for further management. Conclusion Some times, it may become clinically challenging to effectively rule out contraindications to a procedure by the gold standard modalities, specially when a patient is collapsing on the table and the clock is ticking. In such scenarios, immediate alternate approaches resulting in safe outcomes are indispensable. Likewise, in our case of emergent cardiac tamponade and a suspicious pericardial mass in a crashing patient, Transthoracic echo with Optison proved to be life saving to rule out vascular connections between cardiac mass and coronaries or pericardial fluid, when there was no time for definitive imaging modalities due to rapid deterioration of patient’s clinical status. Abstract P242 Figure.

P1530 Dense spontaneous echo contrast and thrombus in patients on new oral anticoagulant and warfarin therapy: a retrospective audit

Abstract Background Cardioembolic stroke is a known complication of atrial fibrillation (AF), which is increasing in global prevalence. Spontaneous echo contrast (SEC) in the left atrium (LA) is a precursor for thrombus formation detected on transesophageal echocardiography (TEE). There is limited data regarding the prevalence of dense SEC and/or left atrial thrombus (LAT) detected by TEE in patients on novel oral anticoagulants (NOACs) compared with Warfarin. Purpose To determine and compare the prevalence of dense SEC and/or LAT among patients with AF/atrial flutter undergoing TEE while on continuous NOAC or Warfarin therapy. Methods Retrospective analysis of prospectively entered data for all patients who were on continuous oral anticoagulants and underwent TEE with DC cardioversion, over a 9-year period (1st January 2011 to 31st December 2018) at a public teaching hospital in NSW, Australia. SEC was classified according to emptying flow velocities, as per the European Association of Cardiovascular Imaging guidelines. Results Among the 195 patients, 94 (48%) patients were on NOAC therapy (52% Apixaban, 25% Rivaroxaban, 23% Dabigatran) while 101 (52%) patients were on Warfarin. There was no difference in age (mean ± SD: 64 ± 12 vs. 65 ± 13, p = 0.71) or proportion of males (71% vs 69%, p = 0.76) between patients on NOAC therapy compared with Warfarin. However, the NOAC therapy group had a lower prevalence of ischaemic heart disease (IHD) (18% vs. 33%, p &amp;lt; 0.05) and chronic kidney disease (CKD) (2% vs. 19%, p &amp;lt; 0.001), in addition to a lower CHA2DS2-VASc score (2.1 ± 1.7 vs 2.7 ± 1.7, p = 0.03) and higher haemoglobin levels (145.3 ± 19 vs 133.8 ± 24, p = 0.001). The overall rate of dense SEC and/or LAT detected by TEE was 9.7%. There was no significant difference in the prevalence of dense SEC and/or LAT between patients on NOACs and Warfarin (6.4% vs. 12.9%, p = 0.13). On multivariable analysis of IHD, CKD, Warfarin, NOACs and CHA2DS2-VASc score, there was no significant difference in prevalence of SEC/LAT between Warfarin and NOACs. Conclusions In this study, 6.4% of patients on continuous NOACs and 12.9% of patients on Warfarin therapy had dense SEC and/or LAT detected by TEE. Although the trend towards higher rates of dense SEC and pre-thrombus in the Warfarin group did not reach statistical significance, it still holds clinical significance as these patients cannot be cardioverted. Therefore, these data support the need to consider anticoagulant optimisation in the overall management of patients with SEC.

370 Left Atrial Thrombus and Dense Spontaneous Echo Contrast Among Patients on Apixaban, Dabigatran, and Rivaroxaban

Despite optimisation of oral anticoagulation, left atrial (LA) thrombus is often detected among patients with atrial fibrillation (AF) or flutter (AFL) undergoing transoesophageal echocardiography (TOE). Our aim was to evaluate the prevalence of LA thrombus and SEC in patients with AF or AFL undergoing Apixaban, Dabigatran, or Rivaroxaban therapy. Single-centre, retrospective analysis of all patients who underwent TOE prior to direct-current cardioversion for AF or AFL, between 1st January 2011 and 31st December 2018. All 108 patients (72% male; mean age 64.3±12 years) were on novel oral anticoagulants (NOACs) as follows; 22%(n=24) on Dabigatran, 27%(n=29) on Rivaroxaban and 51%(n=55) on Apixaban. AF patients comprised 83%(n=90) of the study population while 17%(n=18) had AFL. The median BMI was 31(IQR 26-36) and median CHA2DS2-VASc score was 2(IQR 1-3). LA was severely dilated in 16% of all patients. TOE detected LA thrombus in 1.9%(n=2) of patients (located in the LA appendage) and dense spontaneous echo contrast (SEC) in 4.6%(n=5) of patients. SEC was classified according to emptying flow velocities, as per cardiovascular imaging guidelines. LA thrombus and/or dense SEC was prevalent in 5.6%(n=6) of patients (Apixaban 3.6%, Dabigatran 8.3%, and Rivaroxaban 6.9%, p=0.66). Patients with LA thrombus and/or SEC had a median CHA2DS2-VASc score of 3(IQR 2-5). The prevalence of LA thrombus in a cohort of patients anticoagulated with NOACs is low but important. All three NOAC agents are equally effective in preventing LAT and/or SEC. Further larger studies are warranted to confirm this result.

284 An Audit of Severe Spontaneous Echo Contrast and Left Atrial Thrombus in Patients on NOAC and Warfarin Therapy

284 An Audit of Severe Spontaneous Echo Contrast and Left Atrial Thrombus in Patients on NOAC and Warfarin Therapy

496 A fatal case of MitraClip thrombosis

Abstract Case An 80 year old man presented with persistent dyspnea two months following placement of three MitraClip devices for severe degenerative mitral regurgitation (MR). On exam, he had an apical holosystolic murmur. A transesophageal echocardiogram revealed displacement of one of the MitraClip devices (Figure 1A, red arrow showing the displaced MitraClip) and moderate-severe MR (Figure 1B). He underwent implantation of a fourth MitraClip with reduction of his MR to mild-moderate (Figure 1C, 1D; yellow arrow showing the new MitraClip). Shortly after, he experienced severe melena and hematochezia and became lethargic and hypotensive. He was transferred to the Cardiac Intensive Care Unit, was intubated and aggressively supported. Extensive work-up revealed diffuse gastric body ischemia and ulceration. A transthoracic echocardiogram showed his most recent MitraClip being well seated with mild-moderate MR. He developed refractory multi-organ failure and expired eight days following the procedure. Autopsy revealed thrombi attached to the initially placed MitraClip’s (Figure 1E, 1F) and thromboemboli to the small bowel, spleen and brain. Discussion MitraClip is the predominant non-surgical alternative for percutaneous mitral valve repair in inoperable patients with symptomatic MR, either primary or secondary. Despite its growing use, there remains a paucity of data on its safety and the potential life-threatening complications, especially when more than one device are placed. Current recommendations include dual antiplatelet therapy with aspirin and clopidogrel. In patients already on anticoagulation, continuation of it is recommended. Very few cases of MitraClip thrombosis have been reported so far. Acute development of spontaneous echo contrast (SEC) and early thrombus was described in a patient with severe, primary MR receiving 2 MitraClip"s. Both SEC and the early thrombus resolved once the second device was removed. In another case, intraprocedural thrombus formation was described on the right side of the interatrial septum close to the MitraClip guide catheter. The underlying pathophysiologic mechanism and the predisposing factors to acute and subacute thrombosis associated with MitraClip are unclear. One plausible explanation could be the acute dramatic hemodynamic alterations related to the reduction in MR and new mild mitral stenosis. In addition, the MitraClip itself may act as a prothrombotic nidus. Potential risk factors include: advanced age and multiple comorbidities predisposing to proinflammation and prothrombosis. The use of MitraClip is only expected to increase in the future. Large scale clinical trials are needed to further define the safety of the device and delineate the optimal antiplatelet and/or antithrombotic regimen. Abstract 496 Figure. Pre and post TEE and autopsy findings.

Relationship between spontaneous echo contrast and hematological markers in patients with rheumatic mitral stenosis

Systemic thromboembolism is a serious morbidity and mortality cause for patients with rheumatic mitral stenosis (MS). Previously conducted researches showed that spontaneous echo contrast (SEC) found in the left atrium can constitute a risk factor for thrombus formation. The aim of this study is to evaluate the role of echocardiographic and hematologic parameters in anticipating the presence of SEC in the left atrium of patients with severe RMS. This retrospective study includes all patients who were diagnosed with severe and very severe (MS) between 2014 and 2016. They were then divided in two groups depending on SEC presence. There were 29 patients (30%) in the SEC positive group (group I) and 71patients (70%) in the SEC negative group (group II). A CRP greater than 10 was found in 59% of patients with SEC, versus 21% in the second group. There was no significant difference in blood counts between the two groups. An ACFA was scored in 71% in first-group patients, versus 34% in the second group. Patients with SEC, had a left atrium dilated in 82% versus 37% in the second group. Also, MS was very tight in this population. In addition to the very tight nature of the MR, the volume of left atrium and heart rhythm, CRP was found to be related to left atrial SEC presence in patients with severe MS.

P921 Left atrial appendage flow velocity (LAAV) and n-terminal pro brain natriuretic peptide (NT-proBNP) as strong predictors of high thromboembolic events in patients with nonvalvular atrial fibrillatio

Abstract Background Many studies demonstrated that the presence of non valcular atrial fibrillation (NVAF) increased the risk of cardioembolic stroke from fivefold to sixfold. Cardioembolic stroke is commonly sourced by thrombi in Left Atrial Appendage (LAA) and since this is a treatable condition, early detection would be highly beneficial for a better prognosis. Aim : The aim of this study was to investigate the change of LAA flow felocity (LAAV) and its correlation with NT-proBNP plasma levels, Left atrial spontaneous echo contrast (LASEC) and CHA2DS2-Vasc score, as well as evaluating the prognostic value of these parameters in detecting thromboembolic events in patients with NVAF. Methods A non-interventional, cross-sectional observational study of 31 people with NVAF. Baseline patient characteristics, CHA2DS2-Vasc score, the five-grades of LASEC, NT-proBNP plasma levels were measured and LAAV visualized by transesophageal echocardiography (TEE) were performed. Results : LAAV were correlated with NT-proBNP (r = -0,511 , p = 0,003), high degree of SEC (r= -0,866 , p &amp;lt; 0,0001) and high CHA2DS2-VASc Score (p = 0.004). In addition, the receiver operating characteristic analysis revealed that the best cut-off value of NT-proBNP to predict higher risk of thromboembolic evants in patientswas 1052pg/mL with 76% sensitivity and 83.3% specificity (area under the curve: X2 = 7,441, p = 0.003). In the subgroup analysis based on different CHA2DS2-VASc scores, the predictive value of NT-proBNP remained significant in patients with a CHA2DS2-VASc score of ≥ 2. Conclusion LAAV were significanty correlated positively with NT-proBNP levels, degrees of SEC and CHA2DS2-VASc score. Plasma NT-proBNP along with CHA2DS2-VASc score were strong predictors of thromboembolic events in patients with NVAF