Acute Onset Atrial Fibrillation Research Articles

Heterogeneity in the role of emergency physicians and treatment of acute atrial fibrillation in emergency departments—results of the International Atrial Fibrillation Background (AFiB) Study

The consept of emergency departments (EDs) with specialized teams of emergency physicians originated in the United Kingdom and the United States during the 1970s and was expanded across most European countries in the twenty-first century. Among the various cardiac arrhythmias encountered in EDs, atrial fibrillation (AF) is the most prevalent, contributing to ED congestion. Existing guidelines offer multiple treatment options for acute-onset AF occurring within 48 hours. The aim of The Atrial Fibrillation Background Study is to evaluate treatment strategies, practices and the role of emergency physicians in managing acute-onset AF in Western medical tradition across Europe, the United States and China (Hong Kong). The data for this nonexperimental survey were collected through a questionnaire administered to the medical director or a senior physician at each of the 12 participating EDs. We obtained information regarding the total number of physicians employed in these EDs, their respective specialties, and the patient caseloads they managed. Additionally, we gathered data on the diagnostic and treatment protocols employed for atrial fibrillation (AF). In the investigated EDs in Hong Kong, the United Kingdom and the United States, patients were treated by emergency physicians. Comparatively, many European EDs primarily relied on physicians with traditional medical specialties. Diagnostic methods employed for acute AF ranged from point-of-care testing to comprehensive laboratory panels and echocardiography. In terms of AF treatment, rate control was the preferred approach in Hong Kong and the USA EDs, while rhythm control was preferred in European settings. Regarding rhythm control, there were considerable variations in preferences between pharmacological and electrical cardioversion methods. Findings from the AFiB Study highlight the growing significance of emergency physicians in the management of acute AF, as well as the divergent treatment approaches for acute AF observed in EDs between Europe and the United States.

Effectiveness and Safety Profiles of Vernakalant for Cardioversion of Acute-onset Atrial Fibrillation: A Systematic Review and Meta-analysis

PurposePharmacologic cardioversion is an effective clinical strategy for fibrillation. Vernakalant is a novel drug used to treat atrial fibrillation (AF). This study aimed to evaluate the efficacy- and tolerability-related data on vernakalant from clinical trials. MethodsLiterature from PubMed and the Cochrane Library was systematically reviewed, and 139 eligible studies were found after specific key words were identified. Twelve randomized clinical trials discussing vernakalant cardioversion in patients with AF were chosen for the meta-analysis after scrutiny. Ten of the 12 trials used placebo while two reported data on active and established drugs to compare the effects of vernakalant. Three of the 12 trials included relevant clinical states in addition to AF. FindingsIn this meta-analysis of data from 12 studies (2365 patients, 887 events), the rate of cardioversion from AF to sinus rhythm (SR) was significantly greater with vernakalant compared with placebo and active comparators (risk ratio = 5.60; 95% CI, 2.83–11.09; I2 test for heterogeneity, 92%). Tolerability-related data revealed that dysgeusia, paresthesia, atrial flutter, and hypotension were major adverse events that occurred with vernakalant use, but the data were not clinically significant compared to placebo and active drug (risk ratio = 1.13; 95% CI, 0.86–1.47). Eleven deaths were reported in 4 trials, with vernakalant directly implicated in two deaths. Vernakalant was well tolerated and effective in patients with rapid-onset AF. ImplicationsVernakalant appears to be a good choice when AF is manifested postoperatively or exists with ischemic heart disease and valvular states. Tolerability-related data are promising, but a specific trial may be required to identify the causes of the deaths considered unrelated to vernakalant use.

Relationship Between Atrial Fibrillation Recurrence and Frontal QRS-T Angle After Effective Cardioversion.

Maintaining sinus rhythm is important in the management of atrial fibrillation (AF). After cardioversion, there is a significant probability of AF recurrence. There is limited research on the relationship between AF recurrence and ECG parameters. This study aimed to evaluate whether the frontal plane QRS-T angle (fQRS-T), a predictor of ventricular heterogeneity, could be used to predict AF recurrence following cardioversion. The study was conducted as a retrospective observational study. Patients diagnosed with acute-onset AF for the first time were included in the study. All patients underwentan ECG after cardioversion, and ECG parameters were evaluated. The patients were separated into two groups based on the presence of AF recurrence during hospitalization after cardioversion. The relationship between the fQRS-T and AF recurrence was also examined. A total of 162 patients, comprising 68 women (41.9%) and94 men (58.1%) with an average age of 59.4±6.5 years, were enrolled in the research. Based on the patient monitoring device findings, patients were separated into two groups: non-recurrent AF (n=118) and recurrent AF (n=44). P-wave duration was significantly longer in the recurrence group (p=0.009). The recurrence group's mean fQRS-T was significantly higher (p<0.001). AF recurrence was substantially higher in patients with fQRS-T >90 ° compared to those with fQRS-T ≤90 ° (56.1% vs. 14.2%, p <0.001). Increased fQRS-T>93.7 ° indicated AF recurrence with 78.3% sensitivity and 83.4% specificity (AUC {area under curve}:0.748, p < 0.001). In multivariate analysis, fQRS-T was revealed to be an early indicator of recurrent AF (OR: 1.882, 95%CI: 1.358-2.881, p<0.001). The fQRS-T, an easily determinable parameter from automatic identification ECG recordings, may be useful for predicting the early return of AF after successful cardioversion.

Intravenous Magnesium Sulfate Reduces the Need for Antiarrhythmics during Acute-Onset Atrial Fibrillation in Emergency and Critical Care.

Several studies have suggested the potential role of Magnesium Sulfate (MgSO4) for the treatment of Atrial Fibrillation (AF) but, in clinical practice, the use of magnesium is not standardized although it is largely used for the treatment of supraventricular arrhythmias. Objectives. We evaluated the role of MgSO4 infusion in association with flecainide in cardioversion of patients presenting in ED with symptomatic AF started less than 48 h before. We retrospectively searched for all patients presented in ED from 1 January 2019 to 31 December 2019 requiring pharmacological cardioversion with flecainide 2 mg/kg. Ninety-seven patients met these criteria, 46 received the administration of intravenous MgSO4 2 gr (Group A), and 51 did not (Group B). Among the 97 patients, the overall cardioversion rate was 85.6%, 91.3% in Group A and 80.4% in Group B. In 27 patients out of 97, the Flecainide was not administered because of spontaneous restoration of sinus rhythm of 9 pts (Group B) and 18 pts (Group A). We also found a statistical significance in the HR at the time of cardioversion between Group A (77.8 ± 19.1 bpm) and Group B (87 ± 21.7 bpm). No complications emerged. The association between MgSO4 and Flecainide has not yielded statistically significant results. However, in consideration of its high safety profile, MgSO4 administration may play a role in ED cardioversion of acute onset AF, reducing the need for antiarrhythmic medications and electrical cardioversion procedures, relieving symptoms reducing heart rate, and reducing the length of stay in the ED.

Atrial fibrillation debut following first electroconvulsive therapy combined with venlafaxine: a case report and a literature review

IntroductionCardiovascular events (CVE) are infrequent adverse effects in patients receiving electroconvulsive therapy (ECT). Nonetheless, it constitutes a threat for patient’s life and may compromise continuing ECT.ObjectivesTo describe a case of acute-onset atrial fibrillation under combined therapy with ECT and venlafaxine.MethodsWe present a 76-year-old man diagnosed of delusional disorder and without any previous CVE, who was hospitalized in our acute psychiatric unit by major depressive episode with psychotic symptoms resistant to pharmacological treatment (valproic-acid 100mg/d, haloperidol 6mg/d, venlafaxine 300mg/d). ECT was initiated presenting atrial fibrillation after first session of ECT, requiring amiodarone and anticoagulant treatment for stabilization. Second session of ECT was delayed for three-weeks, worsening the psychiatric symptoms. Haloperidol was discontinued initiating lurasidone with better cardiovascular profile.Results CVE occur in 2% of the patients receiving ECT, being acute arrhythmia the most frequent one. Among them, few cases of atrial fibrillation (AF) under ECT have been reported. It has been hypothesised that initial vagal response followed by catecholamine surge secondary to ECT could facilitate the development of AF. In addition venlafaxine, an antidepressant drug, may also predispose to arrhythmia in high-risk individuals. High doses of venlafaxine (&gt;300mg/d) combined with ECT have been related with an increment of CVE.ConclusionsAlthough clinically effective for the treatment of major depression disorder, combined therapy of ECT and venlafaxine could precipitate the start of a CVE in genetically susceptible individuals. Therefore, identify and clarify potential risk factors other than previous history of CVE is critical to reduce morbidity and mortality in these patients.DisclosureNo significant relationships.

Anticoagulation in Atrial Fibrillation Cardioversion: What Is Crucial to Take into Account.

The therapeutic dilemma between rhythm and rate control in the management of atrial fibrillation (AF) is still unresolved and electrical or pharmacological cardioversion (CV) frequently represents a useful strategy. The most recent guidelines recommend anticoagulation according to individual thromboembolic risk. Vitamin K antagonists (VKAs) have been routinely used to prevent thromboembolic events. Non-vitamin K antagonist oral anticoagulants (NOACs) represent a significant advance due to their more predictable therapeutic effect and more favorable hemorrhagic risk profile. In hemodynamically unstable patients, an emergency electrical cardioversion (ECV) must be performed. In this situation, intravenous heparin or low molecular weight heparin (LMWH) should be administered before CV. In patients with AF occurring within less than 48 h, synchronized direct ECV should be the elective procedure, as it restores sinus rhythm quicker and more successfully than pharmacological cardioversion (PCV) and is associated with shorter length of hospitalization. Patients with acute onset AF were traditionally considered at lower risk of thromboembolic events due to the shorter time for atrial thrombus formation. In patients with hemodynamic stability and AF for more than 48 h, an ECV should be planned after at least 3 weeks of anticoagulation therapy. Alternatively, transesophageal echocardiography (TEE) to rule out left atrial appendage thrombus (LAAT) should be performed, followed by ECV and anticoagulation for at least 4 weeks. Theoretically, the standardized use of TEE before CV allows a better stratification of thromboembolic risk, although data available to date are not univocal.

PREDICTING UNSUCCESSFUL ELECTRICAL CARDIOVERSION FOR ACUTE ATRIAL FIBRILLATION (FROM THE AF-CVS SCORE)

Background: Despite good progress in the management of patients with atrial fibrillation, this arrhythmia remains one of the major causes of stroke, heart failure, sudden death, and cardiovascular morbidity in the world. Furthermore, the number of patients with AF is predicted to rise steeply in the coming years. Objective: To validate a clinical risk stratification tool (AF-CVS score) for identifying patients at high risk for unsuccessful outcome after electrical cardio-version for acute AF. Patients and Methods: The present study was a cohort study conducted between March 2018 and March 2019. We enrolled 100 consecutive patients admitted at Al-Hussain University, Al-Azhar University, presented with acute onset atrial fibrillation (AF) requiring direct current electro-version (DC electro-version). An informed consent obtained from every patient after full explanation of the research objectives and the purpose of this study. Results: A binary logistic regression was run to evaluate AFCVS score as a predictor for the recurrence among the patients in the study population. There was homoscedasticity and normality of the residuals. The binary logistic regression model was statistically significant (χ2= 28.01, df 1, p= < 0.001) with insignificant Hosmer and Lemeshow test (p 0.114). AFCVS score was a significant predictor for the AF recurrence in the studied population (p < 0.001). The diagnostic efficacy and cut off point of AFCVS for prediction of AF recurrence in the studied sample was determined using a receiver operating characteristic curve (ROC) and the AFCVS score cut off point was 5 . The score showed 83.8% sensitivity, 68.3% Specificity, 87.8% negative predictive value, 60.8% positive predictive value and 74% accuracy. Conclusion: Atrial fibrillation provokes important economic burden along with significant morbidity and mortality. Our study showed that the risk of unsuccessful outcome of ECV can be predicted using five simple clinical variables: A-- Age. F-- not First time AF. C-- Cardiac failure. V-- Vascular disease. S-- Short duration from previous AF (within 1 month before electrical cardio-version (ECV)).

Vernakalant hydrochloride for the treatment of atrial fibrillation: evaluation of its place in clinical practice.

Vernakalant is an intravenous anti-arrhythmic drug available in Europe, Canada and some countries in Asia for the restoration of sinus rhythm in acute onset atrial fibrillation. Currently, it is not available in USA because the US FDA have ongoing concerns about its safety. Vernakalant has a unique pharmacological profile of multi-ion channel activity and atrial-specificity that distinguishes it from other anti-arrhythmic drugs. This is thought to enhance efficacy but there are concerns of adverse events stemming from its diverse pharmacology. This ambiguity has prompted a review of the available clinical evidence on efficacy and safety to help re-evaluate its place in clinical practice.

Prophylaxis for postoperative atrial fibrillation: A quality initiative study exploring adherence to NICE guidance in a UK tertiary cardiothoracic intensive care unit.

Acute onset atrial fibrillation is a common dysrhythmia experienced by patients following cardiac surgery which can often cause morbidity and extended hospital length of stay. The primary aim of the study was to explore adherence to National Institute for Health and Care Excellence (NICE) guidance which suggests the need for prophylaxis for postoperative atrial fibrillation (POAF). Secondary aims were to explore factors contributing to the development POAF and the impact of POAF on patient-centred outcomes. An analysis consisting of descriptive statistics and regression models was conducted using 138 patient's records who underwent cardiac surgery between January and March 2017. We identified 83 (62%) patients on prophylactic rate control medications prior to surgery. During the study period, a total of 50 patients (36%) developed POAF, of which 28 were on prophylactic medication prior to surgery. Patients who developed POAF had significantly prolonged hospital length of stay compared to those who did not develop POAF. Our study identified a significant proportion of patients not being offered prophylactic rate control prior to cardiac surgery. It is clear that poor patient outcomes are associated with the development of POAF and therefore there is an important need to ensure preventative measures are implemented in guidance relating to the management of these patients. Our results also suggest that tight management of clinical and physiological risk factors prior and during cardiac surgery may improve outcomes in this group of patients and could be considered in future enhanced recovery after cardiac surgery protocols.

Safe Cardioversion for Patients With Acute-Onset Atrial Fibrillation and Flutter: Practical Concerns and Considerations

In this Viewpoint concerns raised by Canadian emergency physicians regarding recommendations 2 and 6 from the recent Canadian Cardiovascular Society 2018 update for atrial fibrillation are discussed. These recommendations narrow the window for safe cardioversion and suggest 4 weeks of anticoagulation for all patients who undergo urgent cardioversion regardless of their CHADS-65 status. We discuss the implications of Grading of Recommendations, Assessment, Development, and Evaluation weak recommendations on the basis of low-quality evidence.

Effectiveness and safety of electrical cardioversion for acute-onset atrial fibrillation in the emergency department: a real-world 10-year single center experience.

ObjectiveDespite limited evidence, electrical cardioversion of acute-onset atrial fibrillation (AAF) is widely performed in the emergency department (ED). The aim of this study was to describe the effectiveness and safety of electrical cardioversion of AAF performed by emergency physicians in the ED.MethodsAll episodes of AAF electrically cardioverted in the ED were retrieved from the database for a 10-year period. Most patients not already receiving anticoagulants were given enoxaparin before the procedure (259/419). Procedural complications were recorded, and the patients were followed-up for 30 days for cardiovascular and hemorrhagic complications.ResultsFour hundred nineteen eligible cases were identified; men represented 69%, and mean age was 61±13 years. The procedure was effective in 403 cases (96.2%; 95.4% in women, 96.5% in men), with considerable differences with respect to the age of the patients, the procedure being effective in 100% of patients aged 18 to 39 and only 68.8% in those >80 years. New ED visits (33/419) were identified within 30 days (31 due to atrial fibrillation/atrial flutter recurrence, 1 due to iatrogenic hypokalemia, 1 due to hypertensive emergency). No strokes, major bleeding, life-threatening arrhythmias or peripheral thromboembolism were recorded. Nine small and mild skin burns were observed.ConclusionElectrical cardioversion is an effective and safe procedure in the vast majority of patients, albeit less effective in patients aged >80 years. It appears reasonable to avoid anticoagulation in low-risk patients with AAF and administer peri-procedural heparin to all remaining patients. Long-term anticoagulation should be planned on an individual basis, after assessment of thromboembolic and hemorrhagic risk.

Frequency of "on-label" use of intravenous diltiazem for rate control in patients with acute-onset atrial fibrillation or atrial flutter.

The study was designed to characterize "on-label" use of i.v. diltiazem in patients with acute atrial fibrillation or flutter (AFF). An IRB-approved, single-center, retrospective, observational design was used. Eligible patients had acute AFF with heart rate >120 bpm and received i.v. diltiazem from June 1, 2012, to June 30, 2014. The primary outcome was frequency of on-label use of i.v. diltiazem, defined as use of at least one FDA-approved weight-based bolus dose followed by an infusion, if appropriate, in the absence of contraindications. A total of 300 patients were screened; 97 patients were included for analysis. I.V. diltiazem was used on-label in only 14 patients (14%). Of the 96 patients who received an initial diltiazem bolus injection, the median dose was significantly higher in patients for whom the diltiazem dose was on-label, as follows: 17.5 mg (interquartile range [IQR]), 10-20 mg vs. 10.0 mg (IQR, 10-20 mg), p < 0.02). Twenty-nine patients (35%) in the off-label group had a therapeutic response to diltiazem alone compared with 8 patients (57%) in the on-label group (p = 0.11). More patients treated with off-label diltiazem bolus injection required additional rate control medications (41% vs. 7%, p < 0.04). In most patients, i.v. diltiazem was not used in accordance with FDA labeling. For most, i.v. diltiazem doses were lower than recommended and many of these patients required additional rate control medications to achieve a therapeutic response.

Acute-Onset Atrial Fibrillation Following an Electrically Induced Generalized Convulsion in a Patient Treated With Clozapine and Electroconvulsive Therapy

Urzal, Fátima MD; Oliveira-Maia, Albino J. MD, MPH, PhD; Barahona-Correa, J. Bernardo MD, PhD Author Information

Red cell distribution width predicts new-onset atrial fibrillation in sepsis patients

Background Sepsis is a major cause of mortality in non-cardiac intensive care units, and ranks 10th among causes of death overall. Acute new onset atrial fibrillation is a common observation in critically ill patients admitted with sepsis, there is a direct relationship with disease severity. The red cell distribution width variations reflects a range of systemic diseases including heart failure, stable coronary disease, acute coronary syndrome and stroke. Objectives In this study, we aimed to investigate the relation between red cell distribution width (RDW) and atrial fibrillation (AF) in critically-ill patients with sepsis. Settings and Design We retrospectively examined 70 sepsis patients (35 sepsis patients with newly developed AF during intensive care unit (ICU) stay and 35 sepsis patients without AF matched with age and sex. We investigated the predictive potential for atrial fibrillation for RDW, Ejection fraction, central venous pressure (CVP), Heart rate and qSofa score. Results The mean age of AF group was 54.49 ± 10.07 vs. 56.26 ± 11.766 for Non-AF group. Baseline Ejection fraction, systolic blood pressure, heart rate and CVP showed no significant differences. RDW on admission was significantly different between groups; 18.94 ± 1.126 (AF group) vs. 14.76 ± 0.97 (Non AF Group). ROC curve analysis was done on AF group to determine cut-off values for RDW. Cut-off point was at 17.6 with 97 % sensitivity and 60.7 % specificity. Conclusions RDW levels were higher in sepsis patients with newly developed atrial fibrillation. An increased RDW level in the patient with sepsis may alert physician on developing or presence of atrial fibrillation.

Propafenone for supraventricular arrhythmias in septic shock—Comparison to amiodarone and metoprolol

PurposeThe occurence of supraventricular arrhythmias associate with an unfavourable prognosis in septic shock. Propafenone could be a feasible antiarrhythmic. Materials and methodsPatients collected over a period of 24months were divided into the three groups based on antiarrhythmic: Group1(amiodarone), Group2(propafenone), Group3(metoprolol). Type of arrhythmia, cardioversion rates, demographic, haemodynamic, laboratory parameters were recorded in the first 24h. The outcome data were compared between the groups. Results234 patients (99.1% ventilated) were included, the prevailing arrhythmia was acute onset atrial fibrillation (AF,69.7%). Except for the dosage of noradrenaline (0.35(0.14–0.78) in Group1(n=142)vs 0.25(0.10–0.50),p<0.01 in Group2(n=78)vs 0.14(0.07–0.25)μg/kg·min,p<0.05 in Group3(n=14)) the ejection fraction of left ventricle, rates of renal replacement therapy, arterial lactate and procalcitonin levels were not different between the groups. The cardioversion rate in Group1(74%) was lower than in Group2(89%) and Group3(92%). ICU and 28-day mortalities of Group1 were not significantly higher than in Group2 and Group3. Multivariate analysis demonstrated higher 12-month mortality in Group1 than in Group2 (HR1.58(1.04;2.38),p=0.03). ConclusionsPropafenone demonstrated a higher cardioversion rate than amiodarone with a similar impact on the outcome. Patients remaining in acute onset arrhythmia did not demonstrate significantly higher ICU, 28-day and 12-month mortalities compared to those successfully cardioverted or to those having chronic AF.

Pharmacologic cardioversion with intravenous amiodarone is likely safe in neurocritically Ill patients

Neurological injury is often associated with cardiac abnormalities, including electrophysiological issues. Cardioversion of acute atrial fibrillation (<48h’ duration) without anticoagulation carries about a 0.7% risk of thromboembolism. There is limited data on managing acute atrial fibrillation specifically in the neuroscience intensive care unit (NSICU) setting. We sought to determine the safety of using intravenous (IV) amiodarone for restoring sinus rhythm in patients with presumed new onset atrial or ventricular tachycardia after neurological injury. We conducted a retrospective review of consecutive patients admitted to our NSICU between June 2011 and March 2015 with a primary neurological diagnosis and new onset tachyarrhythmias who received IV amiodarone. Baseline demographics and presence of known risk factors for atrial fibrillation were recorded. The primary end point was new onset stroke. 48 patients were included for the final analysis. No patients developed new stroke after receiving IV amiodarone. The average follow up period was 14.0days. The majority of patients did not have the pre identified risk factors for atrial fibrillation. Ischemic stroke and traumatic brain injury were the most common admitting diagnoses. We conclude that in patients with primary neurological injury, use of IV amiodarone for rhythm control of acute onset atrial fibrillation carries a low risk of cardioembolic stroke in the first 2weeks. Further investigation, including prospective studies, with larger samples and longer follow up periods is warranted.

Near-infrared spectroscopy-based microcirculatory assessment in acute atrial fibrillation.

Near-infrared spectroscopy is a means of assessing microcirculatory function, but has not been studied in atrial fibrillation (AF). We evaluated the effect of acute AF on thenar eminence near-infrared spectroscopy-derived microcirculatory variables. Stable patients presenting to the emergency department with acute onset AF underwent dynamic near-infrared spectroscopy assessment with a three minute vascular occlusion test (VOT). This was repeated after cardioversion to sinus rhythm (SR). Each assessment included baseline tissue oxygen saturation (StO2), slope of StO2 decrease during VOT, slope of StO2 increase post VOT, minimum and maximum StO2, amplitude of StO2 response and post-ischaemic hyperperfusion. Pre and post cardioversion values were compared by Wilcoxon signed-rank test. Twelve participants (seven male, five female) with a median age of 63 years (interquartile range 52 to 70 years) were enrolled. Median baseline StO2 was 74% before and 77% after cardioversion (P=0.03). The median slope of StO2 decrease during VOT was -0.19%/second and -0.16%/second (P=0.018) and the median slope of StO2 increase post VOT was 3.03%/second and 2.56%/second (P=0.002), pre and post cardioversion, respectively. Minimum StO2 was lower (39% versus 52%, P=0.002) and the amplitude of StO2 response greater (49% versus 40%, P=0.005) in AF, but there was no significant difference in maximum StO2 or the degree of reperfusion hyperaemia. In summary, baseline and minimum StO2 were lower with a greater ischaemic decrease in StO2 during AF, reflecting reduced tissue perfusion, compared with sinus rhythm. Recovery after ischaemia was higher in AF, suggesting normalisation of capillary recruitment during ischaemia.

Abstract 264: Assessing Thromboembolic Risk In Patients Undergoing Direct Electrical Cardioversion Within 48 Hours After Onset Of Atrial Fibrillation

Background: Direct Electrical Cardioversion (DCC) has been known to increase the risk of thromboembolism (TE) in patients with Atrial Fibrillation (AF). However, guidelines and current practices are unclear if this risk exists in patients undergoing DCC &lt; 48 hours after AF onset. We aim to assess TE risk in these patients with and without the use of therapeutic anti-coagulation. Methods: All DCC done at Cleveland Clinic between 1996 to 2012, &lt;48 hours after AF onset were selected from Electrophysiology database. They were divided into two groups on the basis of their anti-coagulation status. We did extensive chart review in these patients to look for outcomes of major TE complications within a month of DCC. Results: Among 567 DCC in 510 patients without therapeutic anti-coagulation, the mean (SD) CHA2DS2-VASc score was 2.34(1.66). At the time of DCC, 54% of these patients were on aspirin, while 12% were on warfarin with INR ≤1.5. There were 7 reported cerebrovascular accidents (CVAs) (1.22%) within a month after DCC. In these 7 patients, the mean (SD) CHA2DS2-VASc score was 3.57(1.27) ranging between 2 to 5. In the second group, 901 DCC were done in 733 patients who were therapeutic on warfarin (63%) or heparin (37%) at the time of DCC. Mean (SD) CHA2DS2-VASc score was 2.61(1.73). There were 2 reported (0.22%, p= 0.016) CVAs within a month after DCC. These two had CHA2D2-VASc scores of 4 and 6. Of these two patients, one was sub- therapeutic (INR=1.14) when he presented with neurological deficits 18 days after the DCC. The other patient held anticoagulation 10 days after DCC for a surgical procedure which was followed by the TE stroke a week later. The non-treated group therefore had a 5.6 times greater odds of having a thromboembolic stroke within a month of DCC (95% CI: 1.16 to 27.14) . Conclusions In patients with acute onset atrial fibrillation, odds of thromboembolic complications are over 5 times higher in patients who did not receive therapeutic anti-coagulation at the time of DCC, despite having a lower baseline stroke risk as defined by their CHA2DS2-VASc scores. In addition, the two patients in our study who did have a stroke in the therapeutically anti-coagulated group had ceased their anticoagulant prior to the stroke.

The concentration of troponin I is increased in patients with acute-onset atrial fibrillation

Some preliminary evidence shows that atrial fibrillation (AF) in patients admitted to the emergency department (ED) with clinical symptoms suggestive of myocardial ischemia is frequently associated with elevations of cardiospecific troponin I (TnI) [1]. Since definitive information about the frequency of troponin release during acute-onset AF (AAF) is lacking to the best our knowledge, we carried out a retrospective observational study by retrieving data from the electronic database of our hospital about all ED visits for AAF (defined as onset of symptoms within 48 hours) recorded in the year 2013. According to currently available guidelines, the definition of AAF included both first-diagnosed AF and paroxysmal AF (PAF) [2]. The ED of the Academic Hospital of Parma is a large urban facility, with approximately 90.000 visits per year. The concentration of TnI was measured in all patients with the contemporary sensitive immunoassay Beckman Coulter AccuTnI, on Unicel DxI (Beckman Coulter, Brea, CA, USA) [3]. The concentration of cTnI was also assessed, during the same period, in a population of 125 ostensibly healthy blood donors (77 males and 48 females, age range 21-54 years), who had this biomarker measured for definition of the local 99 th percentile of the upper reference limit (URL), as specified by the recommendations of the Clinical and Laboratory Standards Institute (CLSI) [4]. Results of TnI were finally expressed as median, interquartile range (IQR) and range (minimum and maximum values). The quality of TnI data was systematically validated throughout the study period by regular internal quality control (IQC) procedures and participation in an External Quality Assessment Scheme (EQAS). Differences between groups were assessed by WilcoxonMann-Whitney test (for continuous variables) and χ 2 test with Yates’ correction (for categorical variables), using Analyse-it (Analyse-it Software Ltd, Leeds, UK). The investigation was performed in accord with the Declaration of Helsinki and under the terms of all relevant local legislation. The 99th percentile URL calculated from our local population of blood donors was 0.03 µg/L. Overall, 474 cases of AAF were recorded in the ED in the year 2013. The median concentration of TnI was found to be significantly higher in patients with AAF (0.01 µg/L; IQR, <0.01 to 0.02 µg/L; range, <0.01 to 0.54 µg/L) than in controls (<0.01 µg/L; IQR, <0.01 to <0.01 µg/L; range, <0.01 to 0.03 µg/L; p<0.001) (Fig. 1). The frequency of values exceeding the 99 th URL was also significantly grater in the group of patients with AAF (86/474, 18%) than in the control population (3/125, 2%; p<0.001). The results of this study confirm the existence of an association between AAF and increased values of TnI, even when this biomarker is measured with a contemporarysensitive immunoassay in a patient population with no symptoms of myocardial ischemia. Due to a substantially increased risk of cardiovascular mortality and morbidity, AF requires an early and appropriate management. AAF represents a frequent reason for ED evaluation and the appropriate management strategy (e.g., rate-control versus rhythm control, antithrombotic therapy) should hence be based on timely risk stratification of stroke, bleeding and cardiovascular morbidity.

Serum potassium levels inversely correlate with D-dimer in patients with acute-onset atrial fibrillation.

BackgroundD-dimer values are frequently increased in patients with atrial fibrillation (AF) compared to subjects in sinus rhythm. Hypokalemia plays a role in several cardiovascular diseases, but little is known about the association with AF.ObjectiveD-dimer values are frequently increased in patients with atrial fibrillation (AF) compared with subjects in sinus rhythm. Hypokalemia plays a role in several cardiovascular diseases, but little is known about the association with AF. The aim of this study was to investigate correlations between D-dimer and serum potassium in acute-onset AF (AAF).MethodsTo investigate the potential correlation between the values of serum potassium and D-dimer in patients with AAF, we retrospectively reviewed clinical and laboratory data of all emergency department visits for AAF in 2013.ResultsAmong 271 consecutive AAF patients with D-dimer assessments, those with hypokalemia (n = 98) had significantly higher D-dimer values than normokalemic patients (139 versus 114 ng/mL, p = 0.004). The rate of patients with D-dimer values exceeding the diagnostic cut-off was higher in the group of patients with hypokalemia than in those with normal serum potassium (26.5% versus 16.2%; p = 0.029). An inverse and highly significant correlation was found between serum potassium and D-dimer (r = −0.21; p < 0.001), even after adjustments for age and sex (beta coefficient −94.8; p = 0.001). The relative risk for a positive D-dimer value attributed to hypokalemia was 1.64 (95% CI, 1.02 to 2.63; p = 0.040). The correlation remained statistically significant in patients free from antihypertensive drugs (r = −0.25; p = 0.018), but not in those taking angiotensin-receptor blockers, angiotensin-converting enzyme inhibitors, or diuretics.ConclusionsThe inverse correlation between values of potassium and D-dimer in patients with AAF provides important and complementary information about the thromboembolic risk of these patients.