Prevalence Of Left Atrial Appendage Thrombus Research Articles

Abstract 17496: Exploring the Benefits: Role of Repeat Transesophageal Echocardiography (TEE) in Patients Anticoagulated for Four Weeks

Background: A left atrial appendage (LAA) thrombus is a well-known complication of atrial fibrillation (AF). Vitamin K antagonists (VKAs) have been well studied been considered the gold standard for thromboembolic prophylaxis. We present a case of LAA thrombus despite compliance with VKAs. Clinical presentation: A 70-year-old female with atrial fibrillation and diabetes presented with left-sided weakness and left facial droop, CT head showed right middle cerebral artery infarct. Vitals were unremarkable. Electrocardiogram showed AF with a rapid ventricular response. She was on warfarin with the most recent international normalized ratio level of 2.3. Transthoracic echocardiography revealed an ejection fraction of 55%, severe left ventricular hypertrophy, and severely dilated left atrium (LA) with LA diameter of 5.3 cm (>= 4.7 cm in women indicates severe dilatation). Transesophageal echocardiography (TEE) with bubble study demonstrated a large thrombus in the LAA with evidence of patent foramen ovale. The pulse wave Doppler (PWD) of the LAA on TEE also showed an LAA velocity of <20 cm/sec, which indicated that there was the highest probability that the thrombus was forming within LAA. Hypercoagulability work-up for thrombosis while on Coumadin such as anti-B2 glycoprotein, anticardiolipin, and factor V Leiden mutation were negative. The patient was started on enoxaparin with appropriate follow-up upon discharge. Discussion: The prevalence of LAA thrombus in patients with AF receiving a minimum of 3 weeks of anticoagulation, was approximately 3%. The presence of a LAA thrombus is a known contraindication to cardioversion and catheter ablation in patients with AF as it can result in cardioembolic stroke. However, current guidelines for cardioversion do not recommend pre-procedural TEE in patients undergoing cardioversion for AF if they have been on therapeutic oral anticoagulation for at least 3 weeks while TEE use remains variable before catheter ablation.

NO CLOT, NO PROBLEM? NOT EXACTLY

NO CLOT, NO PROBLEM? NOT EXACTLY

Risk of left atrial appendage thrombus and stroke in patients with atrial fibrillation and mitral regurgitation

ObjectiveTo investigate the association of mitral regurgitation (MR) on thromboembolic risk of patients with non-valvular atrial fibrillation (NVAF) undergoing transoesophageal echocardiography (TEE)-guided cardioversion.MethodsData for consecutive patients who underwent TEE-guided cardioversion...

Risk of left atrial appendage thrombus in older patients with atrial fibrillation.

We aimed to compare the prevalence of left atrial appendage (LAA) thrombus and its predictors between old and young patients with atrial fibrillation (AF). The study included 1970 patients aged ≥ 65 (n = 822 (41.7%)) and < 65 (n = 1148 (58.3%)) referred for AF cardioversion or ablation preceded by transoesophageal echocardiography (TEE). Oral anticoagulation (OAC) was prescribed in 799 (97.2%) patients aged ≥ 65 years and in 1054 (91.8%) of those aged < 65 years (p < 0.001). In patients treated with OAC, those aged ≥ 65 years less often received vitamin K antagonist (VKA) (267 (33.4%) vs. 416 (39.5%)) and more often non-VKA-OAC (NOAC) (532 (66.6%) vs. 638 (60.5%), p = 0.008, p = 0.008) compared to patients < 65 years. On TEE, LAA thrombus was more often observed in patients aged ≥ 65 years than those aged < 65 years (63 (7.7%) vs. 46 (4.0%), p < 0.001), with an absolute but not statistically significant difference between patients aged 65-74 and ≥ 75 years (47 (7.3%) vs. 16 (8.8%), p = 0.528). In patients aged ≥ 65 years, there was no difference in the prevalence of LAA thrombus between patients treated with VKA and NOAC, in contrast to patients aged < 65 years, in whom such a difference was observed (27 (6.5%) vs. 16 (2.5%), p = 0.002). In multivariate logistic regression, predictors of LAA thrombus in both age groups were older age, non-paroxysmal AF, and heart failure, whereas only in patients aged < 65 years - VKA use, and in those aged ≥ 65 years - lower glomerular filtration rate and platelet count. Despite OAC use, older patients with AF remain at high risk of LAA thrombus formation. Older age, non-paroxysmal AF, and heart failure are predictors of LAA thrombus, irrespective of age.

Prevalence of LAA thrombus in patients undergoing percutaneous ablation of atrial fibrillation

Abstract Introduction Computed tomography (CT) is often performed before atrial fibrillation (AF) ablation to assess the anatomy of the pulmonary veins and exclude left atrial (LA) and left atrial appendage (LAA) thrombus. With the growing use of new oral anticoagulants (NOACs), a reassessment of the need for systematic thrombus exclusion in this context seems warranted. Objective To evaluate the prevalence of thrombus in LA/LAA in pre-ablation CT in a contemporary cohort of patients predominantly anticoagulated with NOACs. Methods We evaluated 789 consecutive patients (mean age 61±12 years; 38% female; 84% with paroxysmal AF) who underwent pre-ablation CT between Oct/2015 and Oct/2019. ECG-gated CT-angiography was performed using a dual-source 64-slice CT after iodinated contrast injection. Whenever necessary, a second dedicated acquisition was made 60 seconds after the first set of images. Presence of thrombus was defined as a persistent opacification defect. For each patient, thromboembolic risk was assessed with the CHA2DS2-VASc score. Results The median interval between CT and AF ablation was 1 day (IQR 1 – 2 days). The median CHA2DS2-VASc was 2 points (IQR 0 – 3 points), with 590 patients (75%) having CHA2DS2-VASc ≥1. Among the 199 patients (25%) with CHA2DS2-VASc = 0, 118 (59,3%) were anticoagulated with a NOAC and 14 (7%) with a vitamin K antagonist; 67 (34%) were not anticoagulated. Conversely, amongst the 590 patients with CHA2DS2-VASc ≥1, 84% were anticoagulated with a NOAC (n=494), 11% used vitamin K antagonists (n=62), and 34 patients were not anticoagulated (23 with CHA2DS2-VASc = 1). On cardiac CT, 521 (66%) patients were in sinus rhythm. Overall, only one LAA thrombus was found (0.12% [1/789]; 95% CI: 0.0–0.7%) – in a patient with CHA2DS2-VASc = 0, anticoagulated with a NOAC. The median effective radiation dose was 3.2 mSv (IQR 2.1–4.8 mSv). There were 5 minor allergic reactions to iodinated contrast. No strokes were documented within the first 24 hours after ablation. Conclusion In this contemporary cohort of patients with predominantly paroxysmal AF and anticoagulated with NOAC, the prevalence of intracavitary thrombus was extremely low (0.12%). While these findings do not compromise the multipurpose role of pre-ablation CT, they should nevertheless inform future discussions on the risk/benefit and cost/benefit of performing systematic exclusion of LA/LAA thrombi prior to AF ablation. Funding Acknowledgement Type of funding source: None

Prevalence and risk factors of left atrial thrombus in patients with atrial fibrillation and lower class (IIa) recommendation to anticoagulants

Oral anticoagulation therapy (OAT) prevents ischaemic incidents in patients with atrial fibrillation (AF). CHA2DS2-VASc risk score of ≥2 points in men and ≥3 in women is a class I indication for OAT. OAT should also be considered as a prevention of thromboembolism in AF men with a CHA2DS2-VASc score of 1 point and women with 2 points, but the class of recommendation is lower (IIa). This study aims to assess the occurrence of left atrial appendage thrombus (LAAT) and risk factors of its formation in patients with lower class recommendation to oral antiocoagulation treatment. The study group consisted of 1,858 patients: 555 patients with class IIa indication to OAT (IIa group) and 1,303 patients with class I indication as a control group (I group). Patients were admitted to three cardiology departments. All subjects underwent transoesophageal echocardiography. The incidence of LAAT was comparable in both IIa and I group: LAAT was confirmed in 30 (5.4%) subjects of IIa group and in 77 (5.9%) of I group. The prevalence of LAAT in IIa group was higher on treatment with VKAs (in comparison to NOACs) (8.4% vs. 3.4%, P=0.010), and lower in case of paroxysmal AF (in comparison to non-paroxysmal AF) (2.4% vs. 9.8%, P=0.0002). Multivariate logistic regression revealed the following variables as the independent predictors of LAAT in IIa group: treatment with VKAs (OR 2.99, 95% CI: 1.33-6.69; P=0.007), paroxysmal AF (OR 0.26, 95% CI: 0.11-0.62; P=0.002) and eGFR <60 mL/min/1.73 m2 (OR 3.19, 95% CI: 1.42-7.16; P=0.005). The prevalence of LAAT in AF patients with lower class (IIa) recommendation to anticoagulants was comparable to higher (I). Treatment with VKAs, along with non-paroxysmal type of AF and eGFR <60 mL/min/1.72 m2 were identified as the strongest predictors of LAAT in IIa group.

Thrombus in the left atrial appendage in patients with atrial fibrillation treated with non-vitamin K antagonist oral anticoagulants in clinical practice-A multicenter registry.

The prevalence and predictors of left atrial appendage thrombus (LAAT) in patients with non-valvular atrial fibrillation (AF) who have been treated with non-vitamin K antagonist oral anticoagulants (NOACs) are not well defined. We aimed to assess the occurrence and predictors of LAAT on transesophageal echocardiography (TOE) in patients with non-valvular AF treated with NOACs for at least 3 weeks. Consecutive patients with non-valvular AF who underwent TOE before catheter ablation or electrical cardioversion in three high-reference centers between 2014 and 2018 were included. Patients on apixaban were excluded from the study due to low numbers in this category. All patients received NOACs for at least 3 weeks before TOE. A total of 1148 patients (female, 38.1%; mean age, 62.1 years) referred to our centers for catheter ablation of AF (52.1%) or electrical cardioversion (47.9%) were included. Patients were on rivaroxaban (51.9%) or dabigatran (48.1%). Preprocedural TOE revealed LAAT in 4.4% of all patients. Multivariable logistic regression analysis showed the CHA2DS2-VASc score ≥2 points (OR = 2.11; 95% CI, 1.15-3.88; P = .0161), non-paroxysmal AF (OR = 6.30; 95% CI, 2.22-17.91; P = .0005), and GFR <60 mL/min/1.73 m2 (OR = 2.05; 95% CI, 1.14-3.67; P = .0160) were independent predictors of LAAT in patients treated with NOACs. In non-valvular AF patients treated with NOACs, the prevalence of LAAT was 4.4% before electrical cardioversion or ablation. In addition to the CHA2DS2-VASc score, the type of AF and renal function should be considered in the stratification of thromboembolism risk in AF patients and qualification for a preprocedural TOE.

Prevalence and Resolution of Left Atrial Thrombus in Patients With Nonvalvular Atrial Fibrillation and Flutter With Oral Anticoagulation

Left atrial appendage (LAA) thrombus in nonvalvular atrial fibrillation or flutter (AF) is a major cause of stroke and presents a therapeutic dilemma in a rhythm-control strategy. The prevalence and resolution of LAA thrombus has not been studied well in the era of non-vitamin K antagonist oral anticoagulant use. This study sought to establish (1) the prevalence of LAA thrombus (2) the prevalence of LAA thrombus despite antithrombotic therapy, (3) the rate of persistence of LAA thrombus despite appropriate anticoagulant prescriptions, and (4) determinants of LAA thrombus persistence. Consecutive transesophageal echocardiograms (TEE) performed in patients with AF were reviewed to estimate the overall prevalence of LAA thrombus and the resolution rate in those with repeat studies. Multivariable logistic regression was used to identify clinical and echocardiographic predictors of thrombus resolution. Of 1,485 patients with AF, 117 (8%) had LAA thrombus. Of those, 62 had repeat TEE within 1 year and 58 (94%) were prescribed adequate anticoagulation in TEE studies (mean interval 96 ± 72 days). Thirty-seven patients (60%) had LAA thrombus resolution. Thrombus resolution rate was only 79% in patients considered on appropriate anticoagulation. Patients with persistent LAA thrombus were more likely to have diabetes; no other clinical or echocardiographic variable was independently associated with thrombus resolution. There was no significant difference in LAA thrombus resolution between non-vitamin K antagonist oral anticoagulants and warfarin. LAA thrombus persistence despite adequate anticoagulation is relatively common and difficult to predict clinically; TEE before electrical cardioversion should be considered regardless of anticoagulation status.

Use of the CHA2DS2VASc score to reduce utilisation of transoesophageal echocardiography prior to ablation for atrial fibrillation

Transoesophageal echocardiography (TOE) is frequently performed prior to atrial fibrillation (AF) ablation to exclude left atrial appendage (LAA) thrombus. However, patients undergoing AF ablation are usually anticoagulated, thus making the presence of thrombus unlikely in most cases. This study aimed to determine whether the CHA2DS2VASc scoring system can be used to identify patients that do not require TOE prior to AF ablation. In this single-centre retrospective study, local institutional and primary care databases and electronic patient records were searched to identify patients that had undergone TOE prior to AF ablation. Patient demographics, CHA2DS2VASc score, TOE findings and anticoagulation status were collected for analysis. Over a 7-year period (2008–2014), 332 patients (age 57 ± 10 years; 74% male) underwent TOE prior to proposed AF ablation. CHA2DS2VASc scores of 0, 1, 2 and >2 were found in 39, 34, 15 and 12% of patients, respectively. The prevalence of LAA thrombus was 0.6% (2 patients) and these 2 patients had risk scores of 2 and 4. No patients with a score of 0 or 1 had LAA thrombus. Patients that are classed as low risk by the CHA2DS2VASc score do not require a pre-ablation TOE to screen for LAA thrombus provided they are adequately anticoagulated. This would lead to a significant reduction in health care expenditures by reducing unnecessary TOE requests and thereby improve patient experience.

Left Atrial Appendage Thrombi Formation in Japanese Non-Valvular Atrial Fibrillation Patients During Anticoagulation Therapy - Warfarin vs. Direct Oral Anticoagulants.

Atrial fibrillation (AF) is a common cardiac arrhythmia, associated with increased cardiovascular morbidity and mortality including thromboembolic events. The aims of this study were to assess the prevalence of left atrial appendage (LAA) thrombi in Japanese non-valvular atrial fibrillation (NVAF) patients undergoing preprocedural transesophageal echocardiography (TEE) during anticoagulation therapy, and to compare the efficacy of warfarin and direct oral anticoagulants (DOAC).Methods and Results:This retrospective study reviewed records of 559 consecutive NVAF patients (445 men; age, 62±11 years) undergoing preprocedural TEE following at least 3 weeks of anticoagulation therapy. Of these, 275 patients had non-paroxysmal AF (49%). LAA thrombus was observed in 15 patients (2.7%). The prevalence of LAA thrombi was similar between the DOAC group (2.6%) and the warfarin group (2.8%, P=0.86). No patients with CHA2DS2-VASc score=0, or paroxysmal AF without prior stroke or transient ischemic attack, had LAA thrombi. On univariate analysis, non-paroxysmal AF, structural heart disease, antiplatelet therapy, larger left atrium, higher brain natriuretic peptide (BNP), reduced LAA flow, and higher CHA2DS2-VASc score were all associated with LAA thrombi. On multivariate analysis, BNP ≥173 pg/mL remained the only independent predictor of LAA thrombi. LAA thrombi were found in 2.7% of Japanese NVAF patients scheduled for procedures despite ongoing oral anticoagulation therapy. Incidence of thrombi was similar for patients on DOAC and on warfarin.

Relationship between body mass index and left atrial appendage thrombus in nonvalvular atrial fibrillation.

Atrial fibrillation and obesity are two major growing epidemics in the United States and globally. Obese people are at the increased risk of developing atrial fibrillation. The contribution of obesity as an independent risk factor for stroke in the setting of atrial fibrillation remains unclear. We tested the hypothesis that non-valvular atrial fibrillation (NVAF) patients with increased body mass index (BMI) would be at increased risk for the development of left atrial appendage thrombus (LAAT). Consecutive, anticoagulation naïve patients with NVAF referred for a transesophageal echocardiogram (TEE) between January 1, 2007 and October 21, 2009 were approached for study participation. All clinical, laboratory, and TEE measurement data were collected prospectively. Within a group of 400 anticoagulation naïve NVAF patients (mean age 63 ± 15 years, 28 % women; 17 % with LAAT) the prevalence of LAAT was similar across all BMI categories (normal 13 %, overweight 19 %, obese 16 %, morbidly obese 16 %; p = 0.71). Despite a higher CHADS2 score and a higher prevalence of both hypertension and diabetes mellitus, elevated BMI was not an independent predictor of LAAT when analyzed as either a continuous variable, across BMI WHO categories, a dichotomous variable stratified at values above versus below 27 kg/m(2), or BMI stratified on atrial fibrillation duration. Despite a higher prevalence of major risk factors for thromboembolism, the prevalence of LAAT was not increased in overweight, obese, and morbidly obese patients.

Abstract 18114: Prevalence of Left Atrial Appendage Thrombus in Oncologic Patients with Atrial Fibrillation

Introduction: There is considerable evidence that the left atrial appendage (LAA) is a common site for thrombus formation and its characteristics pose varying risks for having embolic events. Furthermore, atrial fibrillation has been found to occur with an increased frequency in patients with malignancies. The lack of evidence of standardized treatment strategies in the cancer population forces physicians to take an individualized approach to atrial fibrillation and stroke prevention. Herein, we describe the LAA characteristics in a cancer population with atrial fibrillation. Hypothesis: Cancer patients have an increased risk of LAA thrombus formation in atrial fibrillation. Methods: This is a retrospective study to determine the prevalence of LAA thrombus in a cohort of oncologic patients with atrial fibrillation. Two hundred and forty-five patients underwent transesophageal echocardiogram (TEE) at MD Anderson Cancer Center during the period 2000-2013 for atrial fibrillation evaluation. Results: LAA thrombus was identified in 6.5% of patients (16 of 245). During follow up, three of these patients had experienced a stroke (19%). The mean age was 67 with 5 females (31%) and 11 males (69%). Fifteen patients were white. The majority of patients had solid tumors (75%, 12 of 16). The mean CHADS2 score was 1.3 +/- 0.9 and the mean left ventricular ejection fraction on transthoracic echo was 57 +/- 9%. Spontaneous echo contrast was noted on TEE in 56% of patients (9 of 16). Five patients were on antiplatelet therapy and 9 were on oral anticoagulants. Oncologic, TEE, and clinical data are detailed below (Table 1). Conclusions: The prevalence of LAA thrombus and stroke in cancer patients with atrial fibrillation is significant. These findings may be a reflection of the enhanced inflammatory state of cancer. This data suggest that LAA thrombus evaluation is critical in determining the anticoagulation strategy in atrial fibrillation patients with cancer.

Abstract 8989: Left Atrial Appendage Volume as a Predictor of Left Atrial Appendage Thrombus and Sludge in Patients With Nonvalvular Atrial Fibrillation: A Three-Dimensional Transesophageal Echocardiographic Study

Background: Clinical and echocardiographic predictors for detecting left atrial appendage (LAA) thrombus are well characterized. However, whether the size of LAA measured by two-dimensional transesophageal echocardiography (2D-TEE) predicts the risk of thrombus formation in LAA has been the subject of much controversy. Purpose: The aim of this study was to investigate the ability of LAA volume derived from real-time three-dimensional transesophageal echocardiography (RT3D-TEE) to predict LAA thrombus and/or sludge in patients with nonvalvular atrial fibrillation (NVAF). Methods and Results: A total of 71 patients with NVAF lasting ≥ 1 month and without severe valvular regurgitation, who underwent 2D-TEE and RT3D-TEE, were included in the study. They were divided into two groups according to the presence of LAA thrombus and/or sludge. LAA thrombus and/or sludge were detected in 28 patients (39%). In these patients, the prevalence of LAA thrombus and that of LAA sludge were 54% and 100%, respectively. All 2D and 3D measurements of LAA were performed at ventricular end-systole.A trend was only seen for a significant correlation between LAA volume measured by RT3D-TEE and LAA area in the longitudinal section imaged (usually between 60 and 90 dgrees) by 2D-TEE (r = 0.31, p = 0.08). On multivariable analysis, LAA volume and the ratio of early transmitral flow velocity to peak early diastolic mitral annular velocity (E/e') were found to be significantly predictive of LAA thrombus and/or sludge. Conversely, LAA emptying flow velocity predicted freedom from them (Table 1). Receiver operating characteristic analysis yielded an optimal cutoff value of 14.7 cm 3 for LAA volume to detect LAA thrombus and/or sludge (area under the curve 0.89). The sensitivity and specificity of this model were 79% and 89%, respectively. Conclusion: Our data suggest that increased LAA volume measurements by RT3D-TEE can assist in the detection of LAA thrombus and/or sludge in the patients with NVAF.

052 The prevalence of left atrial appendage thrombus in patients undergoing catheter ablation for atrial fibrillation maintained on warfarin

IntroductionReports of the prevalence of left atrial appendage (LAA) thrombus among patients undergoing catheter ablation for atrial fibrillation (AF) vary and may depend on the anticoagulation regime used prior to...

Arguments Against Left Atrial Appendage Occlusion for Stroke Prevention

To the Editor: With great interest we read the article by Onalan et al about left atrial appendage (LAA) exclusion for stroke prevention in nonrheumatic atrial fibrillation (AF).1 We share the author’s concerns about the hazards of this procedure and would like to emphasize additional arguments. There is no evidence that thromboembolism in AF exclusively derives from LAA thrombi detected by transesophageal echocardiography. The prevalences (4% to 21%) of LAA-thrombi were found in studies of acutely sick patients, patients before cardioversion, cardiac surgery or after recent embolism. Contrarily, when prospectively investigating clinically stable outpatients with AF and no recent embolism by transesophageal echocardiography, the prevalence of LAA thrombi was only …

Diagnosis of Left Atrial Appendage Thrombi by Multiplane Transesophageal Echocardiography Interlaboratory Comparative Study

Transesophageal echocardiography (TEE) is regarded as the method of choice for imaging left atrial appendage thrombi (LAAT). However, the interobserver variability among 2 independent echocardiographic laboratories in diagnosing LAAT by multiplane TEE has not yet been assessed. The videorecordings of 50 patients in atrial fibrillation (25 from each laboratory) were blindly reviewed by 1 experienced observer from each institution. LAAT were assessed as present, absent or questionable. Indications for TEE were: cardioversion (n=17), valve disease (n=13), endocarditis (n=12), or embolism (n=8). The prevalence of LAAT was 10% (observer 1) vs 12% (observer 2). A questionable LAAT was assessed in 6% vs 12% and a LAAT was excluded in 84% vs 76%, respectively. By head-to-head comparison, disagreement occurred in 11 cases (22%, kappa=0.5). Discrepant results were not related to the echocardiographic equipment. Problems occurred because of reverberation artifacts of the ridge between the left atrial appendage and left upper pulmonary vein (n=5), and in differentiating LAAT from spontaneous echocardiographic contrast (n=4) or an echogenic atrioventricular groove (n=1). The differentiation of pectinate muscles from LAAT was the reason for disagreement in only 1 case. Eliminating the category of questionable thrombi increased the kappa value to 0.65. In 5 patients undergoing cardiac surgery, both observers had agreed on the presence (n=1) or absence (n=4) of LAAT, and intraoperatively the results of TEE were confirmed. Even with multiplane TEE, interobserver variability among 2 independent echocardiographic laboratories for diagnosing LAAT remains high because of problems in differentiating LAAT from spontaneous echocardiographic contrast and reverberation artifacts.

Prevalence of left atrial chamber and appendage thrombi in patients with atrial flutter and its clinical significance

OBJECTIVESThe study was done to assess the prevalence of left atrial (LA) chamber and appendage thrombi in patients with atrial flutter (AFl) scheduled for electrophysiologic study (EPS), to evaluate the prevalence of thromboembolic complications after transesophageal echocardiographic (TEE)-guided restoration of sinus rhythm and to evaluate clinical risk factors for a thrombogenic milieu.BACKGROUNDRecent studies showed controversial results on the prevalence of atrial thrombi and the risk of thromboembolism after restoring sinus rhythm in patients with AFl.METHODSBetween 1995 and 1999, patients with AFl who were scheduled for EPS were included in the study. After transesophageal assessment of the left atrial appendage and exclusion of thrombi, an effective anticoagulation was initiated and patients underwent EPS within 24 h.RESULTSWe performed 202 EPSs (radiofrequency catheter ablation, n = 122; overdrive stimulation, n = 64; electrical cardioversion, n = 16) in 139 consecutive patients with AFl. Fifteen patients with a thrombogenic milieu were identified. All of them had paroxysmal atrial fibrillation (AF). Transesophageal echocardiography revealed LA thrombi in two cases (1%). After EPS no thromboembolic complications were observed. Diabetes mellitus, arterial hypertension and a decreased left ventricular ejection fraction were found to be independent risk factors associated with a thrombogenic milieu.CONCLUSIONSThe findings of a low prevalence of LA appendage thrombi (1%) in patients with AFl and a close correlation between a history of previous embolism and paroxysmal AF support the current guidelines that patients with pure AFl do not require anticoagulation therapy, whereas patients with AFl and paroxysmal AF should receive anticoagulation therapy. In addition, the presence of clinical risk factors should alert the physician to an increased likelihood for a thrombogenic milieu.

Structural heart disease in the newborn. Changing profile: comparison of 1975 with 1965.

The earlier detection and investigation of babies with congenital structural heart disease has resulted in earlier treatment and better management of these patients. In 1965, at the Hospital for Sick Children, Toronto, 121 cases were assessed and treated; by 1975 this figure had risen to 226 cases. Few changes were noted in the incidence of the 10 most common malformations, except for the obvious increase in the incidence of patient ductus arteriosus due to survival of increasingly premature infants. The sick cardiac neonate was referred earlier in 1975, studied with newer non-invasive investigations, and, according to the severity of symptoms and signs, was sent sooner to cardiac catheterisation. 80% of babies presenting with cyanosis survived the first month and 60% of babies with congestive heart failure survived. With better surgery and perioperative care, the survival rate in the first month after surgery rose from 37% in 1965 to 70% in 1975.