Systemic Embolism In Patients Research Articles

Heart rate variability and stroke or systemic embolism in patients with atrial fibrillation

BackgroundStroke remains one of the most serious complications in atrial fibrillation (AF) patients and has been linked to disturbances of the autonomic nervous system. ObjectiveThe purpose of this study was to test the hypothesis that impaired cardiac autonomic function might be associated with an enhanced stroke risk in AF patients. MethodsA total of 1922 AF patients who were in either sinus rhythm (SR group; n = 1121) or AF (AF group; n = 801) on a 5-minute resting electrocardiographic (ECG) recording were enrolled in the study. Heart rate variability triangular index (HRVI), standard deviation of normal-to-normal intervals, root mean square root of successive differences of normal-to-normal intervals, mean heart rate, 5-minute total power, and power in the high-frequency, low-frequency, and very-low-frequency ranges were calculated. Cox regression models were constructed to examine the association of heart rate variability (HRV) parameters with the composite endpoint of stroke or systemic embolism. ResultsMean age was 71 ± 8 years in the SR group and 75 ± 8 years in the AF group. Thirty-seven patients in the SR group (3.4%) and 60 patients in the AF group (8.0%) experienced a stroke or systemic embolism during follow-up of 5 years. In patients with SR, HRVI <15 was the strongest HRV parameter to be associated with stroke or systemic embolism (hazard ratio 3.04; 95% confidence interval 1.3–7.0; P = .009) after adjustment for multiple confounders. In the AF group, no HRV parameter was found to be associated with the composite endpoint. ConclusionHRVI measured during SR on a single 5-minute ECG recording is independently associated with stroke or systemic embolism in AF patients. HRV analysis in SR may help to improve risk stratification in AF patients.

Simple scores to predict 1-year mortality in atrial fibrillation.

Traditional scores as CHADS2 and CHA2DS2-Vasc are suitable for predicting stroke and systemic embolism in patients with atrial fibrillation (AF) and have shown to be also associated with mortality. Other more complex scores have been recommended for survival prediction. The purpose of our analysis was to test the performance of different clinical scores in predicting 1-year mortality in AF patients. CHADS2 and CHA2DS2-Vasc scores were calculated for AF patients of the BLITZ-AF register and compared to R2-CHADS2, R2-CHA2DS2-Vasc and CHA2DS2VASc-RAF scores in predicting 1-year survival. Scores including renal function were calculated both with glomerular filtration rate (GFR) and creatinine clearance. One-year vital status (1960 alive and 199 dead) was available in 2159 patients. Receiver-operating characteristic curves displayed an association of each score to all-cause mortality, with R2(ClCrea)-CHADS2 being the best [area under the curve (AUC) 0.734]. Differences among the AUCs of the eight scores were not so evident, and a significant difference was found only between R2(ClCrea)-CHADS2 and CHADS2, CHA2DS2VASc, (ClCrea)-CHA2DS2-VASC-RAF.All the scores showed a similar performance for cardiovascular (CV) mortality, with CHA2DS2VASc-RAF being the best (AUC 0.757), with a significant difference with respect to CHADS2, CHA2DS2VASc, and (ClCrea)CHA2DS2Vasc-RAF. More complex scores, even if with better statistical performance, do not show a clinically relevant higher capability to discriminate alive or dead patients at 12 months. The classical and well known CHA2DS2VASc score, which is routinely used all around the world, has a high sensitivity in predicting all-cause mortality (AUC 0.695; Sensit. 80.4%) and CV mortality (AUC 0.691; Sensit. 80.0%). http://links.lww.com/JCM/A632.

Cardiac imaging correlates and predictors of stroke in patients with atrial fibrillation: a meta-analysis.

New nonclinical parameters are needed to improve the current stroke risk stratification schemes for patients with atrial fibrillation. This study aimed to summarize data on potential cardiac imaging correlates and predictors of stroke or systemic embolism in patients with atrial fibrillation. MEDLINE, EMBASE, and Web of Science were searched to identify all published studies providing relevant data through 16 November 2022. Random effects meta-analysis method was used to pool estimates. We included 64 studies reporting data from a pooled population of 56 639 patients. Left atrial spontaneous echo-contrast [adjusted odds ratio (aOR) 3.32, 95% confidence interval (CI) 1.98-5.49], nonchicken wing left atrial appendage (LAA) morphology (aOR 2.15, 95% CI 1.11-4.18), left atrial enlargement (aOR 2.12, 95% CI 1.45-3.08), and higher LAA orifice diameter (aOR 1.56, 95% CI 1.18-2.05) were highly associated with stroke. Other parameters associated with stroke included higher left atrial sphericity (aOR 1.14, 95% CI 1.01-1.29), higher left atrial volume (aOR 1.03, 95% CI 1.01-1.04), higher left atrial volume index (aOR 1.014, 95% CI 1.004-1.023), lower left atrial reservoir strain [adjusted hazard ratio (aHR) 0.86, 95% CI 0.76-0.98], higher left ventricular mass index (aOR 1.010, 95% CI 1.005-1.015) and E / e' ratio (aOR 1.12, 95% CI 1.07-1.16). There was no association between LAA volume (aOR 1.37, 95% CI 0.85-2.21) and stroke. These cardiac imaging parameters identified as potential predictors of thromboembolism may improve the accuracy of stroke risk stratification schemes in patients with atrial fibrillation. Further studies should evaluate the performance of holistic risk scores including clinical factors, biomarkers, and cardiac imaging.

How the Hemostasis Laboratory Can Help Clinicians to Manage Patients on Oral Anticoagulants.

Oral anticoagulants are widely used to treat or prevent cardiovascular diseases in millions of patients worldwide. They are the drugs of choice for stroke prevention and systemic embolism in patients with non-valvular atrial fibrillation and prosthetic heart valves, as well as for treatment/prevention of venous thromboembolism. Oral anticoagulants include vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs). The hemostasis laboratory plays a crucial role in the management of treated patients, spanning from dose adjustment based on laboratory testing that applies to VKAs to the measurement of drug concentrations in special situations that apply to DOACs. This article aims to overview how the hemostasis laboratory can help clinicians manage patients on oral anticoagulants. Special interest is devoted to the international normalized ratio, used to manage patients on VKAs and to the measurement of DOAC concentrations, for which the role of the laboratory is still not very well defined, and most interferences of DOACs with some of the most common hemostatic parameters are not widely appreciated.

Comparative Safety and Effectiveness of Reduced Doses of Direct Acting Oral Anticoagulants for Stroke Prevention in Atrial Fibrillation

This Nordic observational cohort study aims to assess the effectiveness and safety of reduced-dose direct-acting oral anticoagulants (DOACs) dabigatran, rivaroxaban, and apixaban compared to standard warfarin for stroke prevention in nonvalvular atrial fibrillation. The study, utilizing nationwide administrative databases from Denmark, Sweden, Norway, and Finland, spanned from January 1, 2011 to December 31, 2018 (2017 for Sweden). The cohort included 26,883 patients initiating reduced-dose DOACs and 108,014 comparable warfarin patients. Effectiveness was measured by the composite endpoint of ischemic stroke and systemic embolism, while safety was assessed through intracranial hemorrhage. The meta-analysis across countries revealed similar or lower incidences of ischemic stroke and systemic embolism in patients on reduced-dose DOACs compared to standard warfarin (rivaroxaban: HR 0.93, dabigatran: HR 0.88, apixaban: HR 0.79). Incidences within warfarin groups ranged from 2.16 to 3.71 per 100 person-years, comparable to DOAC recipients. Intracranial hemorrhage rates were generally low, ranging from 0.16 to 1.85 per 100 person-years. In comparison with warfarin patients, meta-analyses yielded HRs for rivaroxaban (1.41), dabigatran (0.35), and apixaban (0.72). In this study, atrial fibrillation patients initiating reduced-dose rivaroxaban and dabigatran exhibited incidences of ischemic stroke and systemic embolism similar to warfarin, and for apixaban, even lower. Rates of intracranial hemorrhage were comparable to or lower for patients on DOACs compared to warfarin.

Delayed Prescribing of Non-Vitamin K Antagonist Oral Anticoagulants (NOACs) in Patients with Low Socioeconomic Status

Background/Objective: Atrial fibrillation (AF) and venous thromboembolism (VTE) are conditions with significant morbidity and mortality when left untreated. American Heart Association guidelines changed in 2019 to make non-vitamin K antagonist oral anticoagulants (NOACs) the preferred method for preventing stroke and systemic embolism in patients with AF or history of VTE. NOACs were first introduced to the United States in 2010 and now include dabigatran, apixaban, rivaroxaban, and edoxaban. There is a dearth of research concerning the speed with which new treatments are prescribed to those in different socioeconomic status (SES) groups. We hypothesized that patients with lower SES were prescribed NOACs later than higher SES counterparts following the introduction of NOACs in 2010.&#x0D; Methods: The IU Cardiovascular Research Consortium/Sidus Dataset was mined for AF and VTE patients prescribed a NOAC between 2010 and 2022. The SES groups were determined using 2020 U.S. Census income data that correlated to patients’ zip codes. The yearly number ofpatients in each SES group were compared to assess for proportional uptake of NOAC prescribing. The primary outcome was the proportion of low SES to high SES prescribing over each year between 2010 and 2022.&#x0D; Results: Low SES patients (n=101,945) were prescribed NOACs at an average of 0.65 times the rate of high SES patients (n= 89,130) from 2010 to 2012, the first three years of NOAC market availability. Prescribing rates equilibrated in 2013 and low SES prescribing has outpaced high SES prescribing since 2021.&#x0D; Conclusion/Impact: Low SES patients experienced a three year delay in receiving NOAC prescriptions at the same rate as their high SES counterparts. Systemic changes, like more frequent prescribing guideline updates and improved evidence-based education amongst providers in low-income areas, could prevent a similar delay when introducing similarly transformative treatments in the future.

Assessment of Bi-Atrial Mechanical Function in Patients with Isolated Atrial Septal Aneurysm.

Atrial mechanical dysfunction may be an alternative mechanism underlying the increased risk of systemic embolism in patients with atrial septal aneurysm (ASA). This study aimed to evaluate left atrial (LA) and right atrial (RA) function using two-dimensional speckle tracking echocardiography (2D STE) in patients with isolated ASA. Fifty-four patients with ASA (mean age 50.3 ± 12.48, 37% male) and 48 healthy individuals of similar age and gender (mean age 48.3 ± 10.84, 39.6% male) were included in the study. To assess atrial mechanical function, measurements of left and right atrial reservoir strain (RS), peak contraction strain (PCS), and conduit strain (CS) were conducted using 2D STE, in addition to conventional evaluation with transthoracic echocardiography. LA RS and PCS values were significantly lower in the ASA group than in the controls (37.52 ± 2.89 vs. 40.16 ± 2.68%, P < 0.001 and 17.29 ± 2.5 vs. 19.18 ± 2.23%, P < 0.001, respectively). Similarly, RA RS and RA PCS were significantly lower in patients with ASA (36.97 ± 2.19 vs. 39.77 ± 2.36%, P < 0.001 and 16.78 ± 2.10 vs. 18.54 ± 2.43%, P < 0.001, respectively). A multivariate regression analysis revealed a strong independent association between ASA and the measures LA RS, LA PCS, RA RS, and RA PCS. Our findings indicate that bi-atrial function are diminished in patients with isolated ASA. This may be a possible cause for the increased risk of arterial embolism in this patient group, aside from atrial arrhythmias and patent foramen ovale. Validating these results with larger studies may influence the treatment and follow-up strategies for patients with isolated ASA.

Anticoagulant-Related Nephropathy in a Patient on Coumadin

Abstract Introduction/Objective Anticoagulant therapy is commonly used to prevent stroke and systemic embolism in patients with atrial fibrillation. However, it carries the risk of bleeding and can lead to serious complications such as anticoagulant-related nephropathy (ARN), a recently described entity characterized by hematuria and acute kidney injury. This report presents a case of a 79-year-old male with a history a patient with a history of atrial fibrillation on coumadin, highlighting the importance of monitoring for anticoagulant-related complications and the need for prompt diagnosis and management to prevent further renal damage. Methods/Case Report The kidney biopsy showed evidence of underlying hypertensive and diabetic nephropathy, with nodular and global glomerulosclerosis, moderate to marked interstitial fibrosis, and tubular atrophy along with many red cell casts of variable ages in the tubules indicative of anticoagulant-related nephropathy. Additionally, one glomerulus had a partial cellular crescent associated with a focus of blood clot, likely related to heavy hematuria. Patient is seronegative for ANCA. The immunofluorescence microscopy is non-contributory due to absence of glomerulus in the sample. Electron microscopy showed diffuse foot process effacement and microvillous transformation of podocytes, increased mesangial matrix, and thickened glomerular basement membranes, but no immune complex deposits. these ultrastructural features confirm the background diabetic nephropathy. Results (if a Case Study enter NA) NA Conclusion Anticoagulant-related nephropathy (ARN) is a rare but serious complication of anticoagulation therapy that can result in hematuria and acute kidney injury. Our case highlights the importance of monitoring for anticoagulant-related complications, especially in high-risk patients with multiple comorbidities. Prompt diagnosis and management of ARN is essential to prevent further renal damage. In this case, despite initial improvement with vitamin K therapy, the patient developed severe renal dysfunction requiring dialysis and renal biopsy. This emphasizes the need for increased awareness and early recognition of ARN in patients on anticoagulant therapy.

Current concepts of treatment for left ventricular thrombus: A sys-tematic meta-analysis comparing direct oral anticoagulants versus vitamin K-antagonists

Abstract Background/Introduction Left ventricular thrombus (LVT) is a dreaded complication after myocardial infarction (MI) and is traditionally treated with Vitamin K antagonists (VKAs) for 3-6 months. Despite a gap of evidence, the broad use of direct oral anticoagulants (DOACs) for other thromboembolic disorders has triggered an increasing off-label use for DOACs in LVTs and has stimulated for expanding research focusing on DOAC´s utility for patients with LVT. Purpose To assess the safety and efficacy of DOACs versus VKAs for the treatment of LVT with a systematic meta-analysis. Methods We conducted a systematic search according to the PRISMA guidelines to identify all existing studies comparing DOACs and VKAs for the treatment of LVT. Forest plots and pooled odds ratios have been calculated for major bleeding events, strokes and systemic embolism, and for thrombus resolution. Results We have included a total of 13 studies with a pooled sample size of 2243 patients. 601 patients (26.8%) were treated with DOACs and 1642 patients (73.2%) with VKAs. The mean age was 55 and 59 years in the DOACs and VKAs group and sex was equally distributed with a male predominance of 81% in both groups. As underlying heart disease, most patients suffered from acute or chronic ischemic cardiomyopathy and presented with a mean left ventricular ejection fraction (LVEF) of 32% at admission. Baseline characteristics of patients included in each primary study are summarized in table 1. The pooled odds ratio of stroke or systemic embolism in patients treated with DOACs versus VKAs was 0.84 (95% CI 0.59-1.19) (p= 0.32). Compared to VKAs, we suggest that the use of DOACs may be associated with a reduced risk for major bleeding incidents without reaching statistical significance (OR 0.63 (95% CI 0.39-1.04) (p = 0.07). LVT resolution was similar and independent of the antithrombotic regimen (OR 0.91 (95% CI 0.7-1.19), p=0.50). Conclusions Based on our meta-analysis we conclude that DOACs seem to be non-inferior to VKAs for the treatment of LVT in terms of thrombus resolution, stroke and systemic embolism, and bleeding incidents. Despite these promising findings, several important aspects such as the duration of anticoagulation, and the type and dosing of the DOAC agent are still poorly understood. To close the lack of evidence for DOACs in LVTs, an adequately powered, randomized trial is needed.

Left atrial strain and risk of systemic embolic event in rheumatic mitral stenosis with sinus rhythm

Abstract Backgrounds Stroke and systemic embolism might be an important complication of rheumatic mitral stenosis (MS) even though patients are in sinus rhythm (SR), but the risk of embolic events in this population are not well studied. Purpose We aimed to evaluate the risk factors of embolic events in patients with rheumatic MS and SR. Methods From the multi-center retrospective registry of 2426 patients with rheumatic MS, we included patients with rheumatic MS and SR (n=583) between January 2000 and December 2021. After exclusion of patients who had history of systemic embolic events, taking the anticoagulants, combined significant aortic valve dysfunction, and a history of valve surgery. We finally analyzed 443 patients. The primary outcome was defined as composite of stroke, transient ischemic attack, noncentral nervous system embolism. Results Among 448 patients (77.1% female; mean age, 52.3 ± 10.1 years), systemic embolic events developed in 38 (8.4 %) patients with annual incidence rate of 4.6/100 person-year during mean follow-up period of 96.4 ± 61.1 months (median 94.2 months). Patients who had systemic embolic events were significantly older and had higher the prevalence of hypertension and diabetes than those who did not, without significant differences in left atrial (LA) dimensions, volumes, pulmonary artery systolic pressure. Instead, LA strain was significantly impaired in patients with systemic embolic events (19.1 ± 9.3 vs. 15.5 ± 8.07, p= 0.034). In the multivariate analysis, LA strain was independent predictors of systemic embolic events [HR 0.96, 95 % CI: 0.93-0.99; P = 0.021], after adjustment for confounding factors. The impaired LA strain (LA reservoir strain &amp;lt; 16.6 %) also had incremental prognostic value for development of systemic embolic events over clinical factors and traditional echocardiographic parameters (Figure). Conclusions Impaired LA strain is a predictor of stroke and systemic embolism in patients with rheumatic MS in SR. Considering the risk for embolism, oral anticoagulation might be considered in patients with rheumatic MS in SR and impaired LA strain.Figure

Oral Anticoagulation Use and Left Atrial Appendage Occlusion in LAAOS III.

LAAOS III (Left Atrial Appendage Occlusion Study III) showed that left atrial appendage (LAA) occlusion reduces the risk of ischemic stroke or systemic embolism in patients with atrial fibrillation undergoing cardiac surgery. This article examines the effect of LAA occlusion on stroke reduction according to variation in the use of oral anticoagulants (OACs). Information regarding OAC use was collected at every follow-up visit. Adjusted proportional hazards modeling, including using landmarks of hospital discharge, 1 and 2 years after randomization, evaluated the effect of LAA occlusion on the risk of ischemic stroke or systemic embolism, according to OAC use. Adjusted proportional hazard modeling, with OAC use as a time-dependent covariate, was also performed to assess the effect of LAA occlusion, according to OAC use throughout the study. At hospital discharge, 3027 patients (63.5%) were receiving a vitamin K antagonist, and 879 (18.5%) were receiving a non-vitamin K antagonist oral anticoagulant (direct OAC), with no difference in OAC use between treatment arms. There were 2887 (60.5%) patients who received OACs at all follow-up visits, 1401 (29.4%) who received OAC at some visits, and 472 (9.9%) who never received OACs. The effect of LAA occlusion on the risk of ischemic stroke or systemic embolism was consistent after discharge across all 3 groups: hazard ratios of 0.70 (95% CI, 0.51-0.96), 0.63 (95% CI, 0.43-0.94), and 0.76 (95% CI, 0.32-1.79), respectively. An adjusted proportional hazards model with OAC use as a time-dependent covariate showed that the reduction in stroke or systemic embolism with LAA occlusion was similar whether patients were receiving OACs or not. The benefit of LAA occlusion was consistent whether patients were receiving OACs or not. LAA occlusion provides thromboembolism reduction in patients independent of OAC use.

Outcomes and Safety of Direct Oral Anticoagulants (DOACs) versus Vitamin K Antagonists (VKAs) amongst Patients with Valvular Heart Disease (VHD): A Systematic Review and Meta-Analysis

Background: Both valvular heart disease (VHD) and atrial fibrillation (AF) frequently coexist. AF is an important cause of arrhythmias with a definitive cardiovascular morbidity. The use of either vitamin K antagonists (VKAs/warfarin) or direct oral anticoagulants (DOACs) (also known as new oral anticoagulants (NOACs)) has been the mainstay for preventing stroke and systemic embolism in patients with VHD and/or AF, and this has been broadly discussed. However, there are limited studies on anticoagulation therapy for patients with valvular atrial fibrillation (VAF). The main aim of this meta-analysis was to evaluate the outcomes (stroke–vascular events and intracranial bleeding) following DOAC and VKA treatment amongst patients with VAF. Methods: We identified clinical trials and observational studies published in the last 10 years. A systematic review and a meta-analysis were performed to evaluate the outcomes of patients with valvular atrial fibrillation following DOAC vs. VKA treatment. Data evaluation was performed using Review Manager 5.4; the endpoints were stroke–vascular events and intracranial bleeding following DOAC and VKA treatment amongst VAF patients. Risk ratios (RR) were evaluated with 95% confidence intervals. Using random effects models, forest plots were obtained. Heterogeneity was assessed by using the I2 statistic. Results: Eight studies were included in this metanalysis, and a total of fifteen thousand two hundred and fifteen patients (DOAC (8732) and VKA (6483)) were pooled. We found a significant risk reduction in stroke–vascular events when using DOACs in comparison with using VKAs (pooled RR: 0.76; 95% CI: 0.64–0.90, p = 0.002). A total of 14862 patients (DOAC (8561) and VKA (6301)) were pooled from a total of six studies for intracranial bleeding. We found a significant risk reduction in terms of intracranial bleeding when using DOACs in comparison with using VKAs (pooled RR: 0.43; 95% CI: 0.24–0.77, p ≤ 0.05). Conclusions: When compared to VKAs, DOAC agents were found to have less risk of stroke–vascular events and intracranial bleeding. Further prospective studies are essential to establish the efficacy and safety of DOAC agents in patients with various subtypes of VAF.

Frequency of systemic embolic events in patients presenting with atrial fibrillation

INTRODUCTION: The risk of stroke in patients with atrial fibrillation (AF) is well recognized, but data from a new study published in Circulation now indicate that AF is also associated with an increased risk of extracranial systemic embolic events, and that these thromboembolic events confer high morbidity and mortality.&#x0D; AIM &amp; OBJECTIVE: To determine the frequency of systemic embolic events in patients presenting with atrial fibrillation&#x0D; MATERIAL &amp; METHODS: It was a cross sectional study conducted at Cardiology Ward, Punjab Institute of Cardiology, Lahore for the period of six months i.e. from 1st December 2016 to 31st May 2017. Total 241 patients who will fulfil the selection criteria were enrolled in the study from emergency of PIC, Lahore. Informed consent was obtained from all patients. Their demographic information was also noted. Then patients had undergone venogram for assessment of presence or absence of embolism. All venogram were done by single senior radiologist having at least 4 years’ experience. Reports were assessed and systemic embolism was noted. All this information was recorded on proforma. Patients diagnosed with embolism were managed as per hospital protocol.&#x0D; RESULTS: In this study systemic embolism events were diagnosed in 101(41.91%) patients who presented with AF. These systemic embolism events did not show any statistically significant association with age, gender (male patients with higher frequency for systemic embolism events p-value=0.566), duration of AF (frequency of systemic embolism events was higher in patients with longer duration of AF p-value=0.254) and diabetic history (frequency of systemic embolism events was higher in patients without diabetes, p-value=0.892)&#x0D; CONCLUSION: Results of this study demonstrated a high frequency of systemic embolism in patients presenting with AF. In routine practice systemic embolism often remain unfocused. So it is strongly suggested that as this condition have a potential impact on high morbidity, mortality, and financial healthcare so it should be managed as aggressively as stroke.&#x0D; KEY WORDS: Systemic, Embolic events, Atrial fibrillation

The place of dabigatran in the treatment of patients with atrial fibrillation in the light of modern recommendations

This review is devoted to the aspects of anticoagulant therapy in patients with atrial fibrillation in the light of the modern understanding of this type of arrhythmia as a polymorbid continuously developing syndrome. According to experts, the management strategy of this category of patients is based on an integrated assessment, including the risk of stroke, the presence of symptoms, assessment of structural heart disease and mandatory accounting of concomitant pathology. In this approach, the appointment of anticoagulant therapy as a prevention of stroke in a patient with atrial fibrillation is put in the first place. At the same time, experts emphasize the need for a dynamic reassessment of risks, as well as the use of a multidisciplinary team of specialists to make a complex decision. The review summarizes the basic concepts of the integrated approach, describes various variants of clinical scenarios, including aspects of anticoagulant maintenance of cardioversion and catheter ablation, multicomponent therapy after percutaneous coronary intervention. A separate chapter is devoted to modern algorithms of perioperative management of a patient receiving oral anticoagulants, which is based on the stratification of interventions according to the risk of perioperative bleeding and the characteristics of the anticoagulant prescribed to the patient. The place of dabigatran in the primary and secondary prevention of stroke and systemic embolism in patients with atrial fibrillation is described, studies that served as the basis of the evidence base for the use of dabigatran in patients with atrial fibrillation are presented. The data of register observations, meta-analyses devoted to the evaluation of the efficacy and safety of dabigatran in certain categories of patients (elderly patients, patients with chronic heart failure, diabetes mellitus) are presented, which form the basis of decision-making in real clinical practice.

Predictive Value of D-dimer Levels for Detection of Left Atrial Thrombus in Patients with Rheumatic Severe Mitral Stenosis

Background: Systemic embolism is one of the most common complications of mitral stenosis (MS). Systemic embolism in patients with MS is caused by left atrial (LA) thrombus. Trans Esophageal Echocardiography (TEE) is considered the most reliable in ruling out LA thrombus, however, it is semi-invasive, operator-dependent, and not widely available. On the other hand, D-dimer is an indirect marker of fibrin formation. It reflects the activation of coagulation system. Objective: To measure D-dimer levels in patients with and without LA thrombus and find out predictive value of D-dimer levels to detect LA thrombus. Methods: In this cross-sectional observational study 50 patients with rheumatic severe mitral stenosis have been assessed. Patients underwent Trans Thoracic Echocardiography (TTE) and TEE to rule out LA thrombus. If TTE showed LA thrombus, TEE was not done. Patients were divided into two groups based on presence of LA thrombus; group I- patients with LA thrombus, and group II- patients without LA thrombus. D-dimer level was measured in two groups and comparison was done. Results: D-dimer was significantly elevated in group I compared to group II (2.8±1.9 µg/ml vs. 0.43±0.13µg/ml, p&lt;0.001). Receiver Operator Characteristic (ROC) Curve showed D-dimer level &gt; 0.6 µg/ml can predict LA thrombus with sensitivity of 84% &amp; specificity of 88%. Conclusion: A higher level of D-dimer can predict LA thrombus in patients with rheumatic severe MS, and can be used as a noninvasive marker to rule out LA thrombus in patients with rheumatic severe MS. Bangladesh Medical Res Counc Bull 2022; 48(3): 231-235

Predictors of stroke or systemic embolism in patients with non-valvular atrial fibrillation with CHA2DS2-VASc score of 0

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Anticoagulant therapy has been important for stroke prevention in patients with atrial fibrillation (AF). However, it was not recommended due to its relatively higher risk of bleeding than its lower risk of stroke in patients with a CHA2DS2-VASc score of 0. Purpose This study aimed to evaluate the predictors of stroke in AF patients with very low risk of stroke. Methods Between 1990 and 2020, 542 patients with non-valvular AF (NVAF) with a CHA2DS2-VASc score of 0 followed up for at least 6 months were enrolled. Patients whose only risk factor was female were included as a CHA2DS2-VASc score of 0 in this study. The primary outcome was stroke or systemic embolism. Results The mean age at AF diagnosis was 49.9 years, and 398 (73.4%) were men. During the mean follow-up of 4.7 years, the primary outcome rate was 0.78%/year (stroke, 0.70%/year; systemic embolism, 0.08%/year), and major bleeding and all-cause death occurred in 0.31%/year and 1.02%/year, respectively. The proportions of age ≥50 years at diagnosis, left ventricular end-diastolic dimension (LVEDD) of ≥46 mm, and non-paroxysmal AF in patients with stroke or systemic embolism were significantly higher than in those without. Cox proportional hazard model, age of ≥50 years at diagnosis (hazard ratio [HR] 6.710, 95% confidence interval [CI] 1.811–24.860, P-value=0.004), LVEDD of ≥46 mm (HR 4.513, 95% CI 1.038–19.626, P-value=0.045), and non-paroxysmal AF (HR 5.575, 95% CI 1.621–19.175, P-value=0.006) were identified as independent predictors of stroke or systemic embolism. Patients with all three independent predictors had a higher risk of stroke or systemic embolism (4.21%/year), whereas those without did not have stroke or systemic embolism. Conclusion The annual stroke or systemic embolism rate in NVAF patients with CHA2DS2-VASc score of 0 was 0.78%/year. Age at AF diagnosis, LVEDD, and non-paroxysmal AF were independent predictors of stroke or systemic embolism in patients considered to be at very low risk of stroke.

Transcatheter Left Atrial Appendage Closure.

Atrial fibrillation is the most common arrhythmia worldwide, placing a large population at risk for potentially disabling ischemic strokes, yet an estimated 50% of eligible patients cannot tolerate or are contraindicated to receive oral anticoagulation. Within the last 15 years, transcatheter options for left atrial appendage closure (LAAC) have provided a valuable alternative to chronic oral anticoagulation for reducing risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. With newer generation devices such as Watchman FLX and Amulet gaining approval from the US Food and Drug Administration in recent years, several large clinical trials have demonstrated the safety and efficacy of transcatheter LAAC in a population intolerant to systemic anticoagulation. In this contemporary review, we discuss the indications for transcatheter LAAC and the evidence evaluating the use of various device therapies currently available or in development. We also examine current unmet challenges in intraprocedural imaging and controversies in postimplantation antithrombotic regimens. Several ongoing seminal trials are hoping to clarify the role of transcatheter LAAC as a safe, first-line option for all patients with nonvalvular atrial fibrillation.

Association of Left Atrial Size With Stroke or Systemic Embolism in Patients With Atrial Fibrillation Having Undergone Bioprosthetic Valve Replacement From the BPV-AF Registry.

Background: The left atrial volume index (LAVI) is important for predicting thromboembolism in patients with non-valvular atrial fibrillation (AF), but the utility of LAVI for predicting thromboembolism in patients with both bioprosthetic valve replacement and AF remains unclear. Methods and Results: Of 894 patients from a previous multicenter prospective observational registry (BPV-AF Registry), 533 whose LAVI data had been obtained by transthoracic echocardiography were included in this subanalysis. Patients were divided into tertiles (T1-T3) according to LAVI as follows: T1 (n=177), LAVI=21.5-55.3 mL/m2; T2 (n=178), LAVI=55.6-82.1 mL/m2; T3 (n=178), LAVI=82.5-408.0 mL/m2. The primary outcome was defined as either stroke or systemic embolism for a mean (±SD) follow-up period of 15.3±4.2 months. Kaplan-Meier curves indicated that the primary outcome tended to occur more frequently in the group with the larger LAVI (log-rank P=0.098). Comparison of T1 with T2 plus T3 using Kaplan-Meier curves indicated that patients in T1 experienced significantly fewer primary outcomes (log-rank P=0.028). Furthermore, univariate Cox proportional hazard regression showed that 1.3- and 3.3-fold more primary outcomes occurred in T2 and T3, respectively, than in T1. Conclusions: Larger LAVI was associated with stroke or systemic embolism in patients who had undergone bioprosthetic valve replacement and with a definitive diagnosis of AF.

Analysis of factors related to systemic embolism in patients≥75 years old with non-valvular atrial fibrillation

Objective: To explore the related risk factors for systemic embolism (SE) in patients aged≥75 years with non-valvular atrial fibrillation (NVAF). Methods: A case-control study. NVAF patients aged≥75 years who were hospitalized at the First Affiliated Hospital of Xinjiang Medical University from October 2018 to October 2020 were divided into no SE (n=1 127) and SE (n=433) groups according to the occurrence of SE after NVAF. Multivariate logistic regression was used to analyze SE-related factors in patients with NVAF without anticoagulation treatment. Results: In the multivariate model, the following factors were associated with an increased risk of SE in patients with NVAF: history of AF≥5 years [odds ratio (OR)=2.75, 95% confidence interval (CI) 1.98-3.82, P<0.01], lipoprotein(a)>300 g/L (OR=2.07, 95%CI 1.50-2.84, P<0.01), apolipoprotein (Apo)B>1.2 g/L (OR=1.91, 95%CI 1.25-2.93, P=0.003), left ventricular ejection fraction (LVEF) of 30%-49% (OR=2.45, 95%CI 1.63-3.69, P<0.01), left atrial diameter>40 mm (OR=1.54, 95%CI 1.16-2.07, P=0.003), and CHA2DS2-VASc score≥3 (OR=15.14, 95%CI 2.05-112.13, P=0.01). ApoAI>1.6 g/L was negatively correlated with the occurrence of SE (OR=0.28, 95%CI 0.15-0.51, P<0.01). Conclusions: History of AF≥5 years, lipoprotein(a)>300 g/L, elevated ApoB, left atrial diameter>40 mm, LVEF of 30%-49%, and CHA2DS2-VASC score≥3 are independent risk factors for SE whereas ApoAI>1.6 g/L is a protective factor against SE in patients with NVAF.

Elevated thrombin generation levels in the left atrial appendage in patients with atrial fibrillation

BackgroundAtrial Fibrillation (AF) is the most common sustained tachi-arrhythmia. Thrombus formation in the left atrial appendage (LAA) increases the risk of stroke and systemic embolism in patients with AF. ObjectivesThe aim of this study was to compare thrombin generation in the LAA to the LA among patients with AF. MethodsA cross-sectional study of consecutive patients with AF undergoing pulmonary veins catheter ablation. Blood samples from the femoral vein (FV), right atrium (RA), left atrium (LA), and LAA were collected during the catheter ablation procedures. Thrombin generation was assessed by a Calibrated Automated Thrombogram. The LAA-calibrated automated thrombogram parameters were compared with the RA, LA, and FV. ResultsA total of 47 consecutive patients were enrolled in the study. The endogenous thrombin potential and peak height were significantly higher in the LAA compared with the LA, the mean differences and 95% CI between the LA and LAA were -378.9 (-680.5, -77.2) (nM∗min) and -66.7 (-119.6, -13.8) (nM) in the endogenous thrombin potential and peak height respectively. ConclusionIn patients with AF undergoing catheter ablation, the LAA demonstrated increased thrombin generation compared with the LA. This finding might contribute to the understanding of why the LAA is more predisposed to thrombus formation than the LA. Clinical Trials RegistrationNCT03795883