Pacemakers can automatically identify and catalog atrial high-rate episodes (AHREs). While most AHREs represent true atrial tachyarrhythmia/atrial fibrillation (AT/AF), a review of stored ...electrograms suggests that a substantial proportion do not. As AHREs may lead to the initiation of oral anticoagulation, it is crucial to understand the relationship between AHREs and true AT/AF.
To compare the positive predictive value of AHREs for electrogram-confirmed AT/AF for various atrial rates and episode durations.
By using data from 2580 patients who participated in the ASymptomatic atrial fibrillation and Stroke Evaluation in pacemaker patients and the AF Reduction atrial pacing Trial, all AHREs >6 minutes and >190 beats/min with available electrograms were reviewed to determine whether they represented true AT/AF. The positive predictive value of these AHREs was assessed for episode durations of 6 minutes, 30 minutes, 6 hours, and 24 hours at atrial rates of 190 and 250 beats/min.
Of 5769 AHREs >6 minutes and >190 beats/min, 82.7% were true AT/AF and 17.3% were false positives (predominantly due to repetitive non-re-entrant ventriculoatrial synchrony). False positives dropped to 6.8%, 3.3%, and 1.8% when the threshold duration was increased to 30 minutes, 6 hours, and 24 hours, respectively. Increasing the threshold heart rate to 250 beats/min added little to the positive predictive value when longer threshold durations were used.
By using a cutoff of >6 minutes and >190 beats/min, the rate of false-positive AHREs is 17.3%, making physician review of electrograms essential. For AHREs lasting >6 hours, the rate of false positives is 3.3%, making physician review less crucial.
Abstract The era of gene discovery and molecular medicine has had a significant impact on clinical practice. Knowledge of specific genetic findings causative for or associated with human disease may ...enhance diagnostic accuracy and influence treatment decisions. In cardiovascular disease, gene discovery for inherited arrhythmia syndromes has advanced most rapidly. The arrhythmia specialist is often confronted with the challenge of diagnosing and managing genetic arrhythmia syndromes. There is now a clear need for guidelines on the appropriate use of genetic testing for the most common genetic conditions associated with a risk of sudden cardiac death. This document represents the first ever published recommendations outlining the role of genetic testing in various clinical scenarios, the specific genes to be considered for testing, and the utility of test results in the management of patients and their families.
Abstract The Canadian Cardiovascular Society (CCS) Atrial Fibrillation (AF) Guidelines Committee provides periodic reviews of new data to produce focused updates that address clinically important ...advances in AF management. This 2016 Focused Update deals with: (1) the management of antithrombotic therapy for AF patients in the context of the various clinical presentations of coronary artery disease; (2) real-life data with non-vitamin K antagonist oral anticoagulants; (3) the use of antidotes for the reversal of non-vitamin K antagonist oral anticoagulants; (4) digoxin as a rate control agent; (5) perioperative anticoagulation management; and (6) AF surgical therapy including the prevention and treatment of AF after cardiac surgery. The recommendations were developed with the same methodology used for the initial 2010 guidelines and the 2012 and 2014 Focused Updates. Using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) standards, individual studies and literature were reviewed for quality and bias; the literature review process and evidence tables are included in the Supplementary Material, and on the CCS Web site. The section on concomitant AF and coronary artery disease was developed in collaboration with the CCS Antiplatelet Guidelines Committee. Details of the updated recommendations are presented, along with their background and rationale. This document is linked to an updated summary of all CCS AF Guidelines recommendations, from 2010 to the present 2016 Focused Update.
Abstract Atrial fibrillation (AF) is an extremely common clinical problem with an important population morbidity and mortality burden. The management of AF is complex and fraught with many uncertain ...and contentious issues, which are being addressed by extensive ongoing basic and clinical research. The Canadian Cardiovascular Society AF Guidelines Committee produced an extensive set of evidence-based AF management guidelines in 2010 and updated them in the areas of anticoagulation and rate/rhythm control in 2012. In late 2013, the committee judged that sufficient new information regarding AF management had become available since 2012 to warrant an update to the Canadian Cardiovascular Society AF Guidelines. After extensive evaluation of the new evidence, the committee has updated the guidelines for: (1) stroke prevention principles; (2) anticoagulation of AF patients with chronic kidney disease; (3) detection of AF in patients with stroke; (4) investigation and management of subclinical AF; (5) left atrial appendage closure in stroke prevention; (6) emergency department management of AF; (7) periprocedural anticoagulation management; and (8) rate and rhythm control including catheter ablation. This report presents the details of the updated recommendations, along with their background and rationale. In addition, a complete set of presently applicable recommendations, those that have been updated and those that remain in force from previous guideline versions, is provided in the Supplementary Material.
A systematic evaluation of patients with unexplained cardiac arrest (UCA) yields a diagnosis in 50% of the cases. However, evolution of clinical phenotype, identification of new disease-causing ...mutations, and description of new syndromes may revise the diagnosis.
To assess the evolution in diagnosis among patients with initially UCA.
Diagnoses were reviewed for all patients with UCA recruited from the Cardiac Arrest Survivors with Preserved Ejection Fraction Registry with at least 1 year of follow-up.
After comprehensive investigation of 68 patients (age 45.2 ± 14.9 years; 63% men), the initial diagnosis was as follows: idiopathic ventricular fibrillation (n = 34 50%), a primary arrhythmic disorder (n = 21 31%), and an occult structural cause (n = 13 19%). Patients were followed for 30 ± 17 months, during which time the diagnosis changed in 12 (18%) patients. A specific diagnosis emerged for 7 patients (21%) with an initial diagnosis of idiopathic ventricular fibrillation. A structural cardiomyopathy evolved in 2 patients with an initial diagnosis of primary electrical disorder, while the specific structural cardiomyopathy was revised for 1 patient. Two patients with an initial diagnosis of a primary arrhythmic disorder were subsequently considered to have a different primary arrhythmic disorder. A follow-up resting electrocardiogram was the test that most frequently changed the diagnosis (67% of the cases), followed by genetic testing (17%).
The reevaluation of patients presenting with UCA may lead to a change in diagnosis in up to 20%. This emphasizes the need to actively monitor the phenotype and also has implications for the treatment of these patients and the screening of their relatives.
Abstract The Canadian Cardiovascular Society (CCS) published the complete set of 2010 Atrial Fibrillation (AF) Guidelines in the January, 2011 issue of the Canadian Journal of Cardiology . During its ...deliberations, the CCS Guidelines Committee engaged to a timely review of future evidence, with periodic composition of focused updates to address clinically important advances. In 2011, results were published from 3 pivotal AF trials: the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonist for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF), the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) study, and the Permanent Atrial Fibrillation Outcome Study Using Dronedarone on Top of Standard Therapy (PALLAS), comparing dronedarone with placebo in patients with permanent AF and additional cardiovascular disease risk-factor burden. Each of these large randomized trials provided clear results with major implications for AF management. Other important evidence that has emerged since the 2010 Guidelines includes findings about prediction instruments for AF-associated stroke and bleeding risk, stroke risk in paroxysmal-AF patients, risk-benefit considerations related to oral anticoagulation in patients with chronic kidney disease, and risk/benefit considerations in the use of antiplatelet agents, alone and in combination with each other or with oral anticoagulants, in AF patients. The Guidelines Committee judged that this extensive and important new evidence required focused updating of the 2010 Guidelines with respect to stroke prevention and rate/rhythm control. This report presents the details of the new recommendations, along with the background and rationale.
Incidence of Stroke in Paroxysmal Versus Sustained Atrial Fibrillation in Patients Taking Oral Anticoagulation or Combined Antiplatelet Therapy: An ACTIVE W Substudy Stefan H. Hohnloser, Dimitri ...Pajitnev, Janice Pogue, Jeff S. Healey, Marc A. Pfeffer, Salim Yusuf, Stuart J. Connolly, for the ACTIVE W Investigators The risk of stroke and non-cerebral embolism and the efficacy of oral anticoagulation (OAC) in paroxysmal atrial fibrillation (AF) as compared with sustained AF are not precisely known. ACTIVE W (Atrial Fibrillation Clopidogrel Trial With Irbesartan For Prevention Off Vascular Events) was a trial in 6,706 AF patients comparing OAC to antiplatelet therapy with aspirin plus clopidogrel for prevention of vascular events. The annualized risk of stroke or non-cerebral embolism was 2.0 in paroxysmal AF (n = 1,202) compared with 2.2 in sustained AF (n = 5,495) (relative risk 0.87, 95% confidence interval 0.59 to 1.30, p = 0.496). The incidence of stroke and non-central nervous system embolism was lower for patients treated with OAC irrespective of type of AF.
Abstract Background Identifying patients with atrial fibrillation (AF) using administrative data is important for epidemiologic and outcomes research. Although administrative data cover large ...populations, it is necessary to assess their validity in identifying AF patients. Methods We used Ontario family physician electronic medical records from the E lectronic M edical R ecord A dministrative data L inked D atabase (EMRALD) as a reference standard to assess the accuracy of administrative data algorithms in identifying patients with AF. From a random sample of 7500 adult patients, patients with AF as recorded in family physician records were identified. Results The optimal algorithm consisted of any of: hospitalization or an emergency room code for AF or prescription for an AF-specific antiarrhythmic agent or billing code for cardioversion, or prescription for an anticoagulant that was accompanied by a physician billing code. for arrhythmia. The algorithm sensitivity was 80.7% (95% confidence interval CI, 75.1-86.3), specificity 99.1% (95% CI, 98.9-99.3), positive predictive value 71.1% (95% CI, 65.1-77.1), and negative predictive value 99.5% (95% CI, 99.3-99.7). This algorithm, applied to the Ontario population, resulted in a calculated increase in AF prevalence from 1.68% to 2.36% over the years 2000-2014. Anticoagulation rates for AF patients increased from 53% in 2011 to 60% in 2014. Among AF patients receiving anticoagulants, novel oral anticoagulant utilization increased from < 5% in 2011 to > 50% in 2014. Conclusions Identifying patients with AF can be done using administrative data, and the algorithm can be used to assess trends in disease burden over time and patterns of care in large populations.
Left Atrial Appendage Occlusion Study II (LAAOS II) Whitlock, Richard P., MD, PhD; Vincent, Jessica, MSc; Blackall, Mary Helen, BScN ...
Canadian journal of cardiology,
11/2013, Letnik:
29, Številka:
11
Journal Article
Recenzirano
Abstract Background Occlusion of the left atrial appendage (LAA) is a potential alternative to anticoagulation for patients with atrial fibrillation (AF); however, evidence of its safety and efficacy ...is lacking. The Left Atrial Appendage Occlusion Study II (LAAOS II) explored the feasibility of a definitive trial of LAA occlusion for stroke prevention in AF. Methods A cross-sectional study of 1889 consecutive patients undergoing cardiac surgery was performed to determine the prevalence of AF and risk factors for stroke. We also randomized 51 patients with AF and increased stroke risk to LAA occlusion (n = 26) or no occlusion and oral anticoagulation (n = 25) to assess the rate of recruitment and the safety of LAA amputation. Results In the cross-sectional study, 204 patients (10.8%) had AF and 98 (5.2%) met trial eligibility. Fifty-one patients were recruited into the trial at a rate of 1.6 patients per centre per month. No patient with occlusion had significant bleeding at the LAA site. At 1 year, 4 patients (15.4%) in the occlusion arm and 5 patients (20.0%) in the no-occlusion arm experienced death, myocardial infarction (MI), stroke, noncerebral systemic emboli, or major bleeding (relative risk RR, 0.71; 95% confidence interval CI, 0.19-2.66; P = 0.61). The predominant component of the composite was stroke, with 1 in the occlusion arm and 3 in the no-occlusion arm. Conclusions LAA occlusion can be safely performed at the time of cardiac surgery. A large trial to evaluate the clinical efficacy of LAA occlusion in patients undergoing cardiac surgery is possible in motivated centres with some modifications to the design of LAAOS II.
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