Society GuidelinesThe 2014 Atrial Fibrillation Guidelines Companion: A Practical Approach to the Use of the Canadian Cardiovascular Society Guidelines
Section snippets
What Duration of AF Is Clinically Significant?
The detection of an irregularly irregular heart rhythm on heart rhythm monitoring (eg, via ambulatory electrocardiogram [ECG] or implantable electronic device) suggests a diagnosis of AF. There is extensive evidence for a relationship between the duration of AF paroxysms and stroke risk.4, 5 Oral anticoagulation with vitamin-K antagonists or a novel non-vitamin K antagonists (NOACs) reduce stroke risk, but carry the disadvantages of increased risk of bleeding, cost, and/or a need for
How Were the Risk Factors in the CCS Algorithm Derived?
The accuracy of various schemas for the prediction of stroke risk in patients with nonvalvular AF (NVAF), the validity of their individual components for estimation of annual stroke incidence, and differences among national guidelines with respect to their recommendations for antithrombotic therapies are actively debated.11, 12, 13 Accordingly, it is timely to review the origins of the most widely used risk prediction schemas and the data underlying recommendations for antithrombotic therapies.
Validation of Risk Prediction Schema
The CHADS2 index was validated in a cohort of 1733 US Medicare recipients aged 65-95 years, who had nonrheumatic AF documented during an index hospitalization, and who were not prescribed warfarin at hospital discharge.17 Patients were followed for a median of 1 year for the outcome of hospitalization for ischemic stroke or TIA.
Subsequently, the CHADS2 index and CHA2DS2-VASc schema have been validated in a cohort of patients in the Euro Heart Survey aged ≥ 18 years, who were free of mitral
What Are the Definitions of Stroke Risk Factors in the CCS Atrial Fibrillation Guidelines Update?
The 2014 CCS Atrial Fibrillation Guidelines update used the CHADS2 index with the evolved definitions of its component risk factors for stroke (termed the CCS Algorithm).3 The evolved definitions were not explicitly stated in the CCS Atrial Fibrillation Guideline update and are now detailed in Table 1. Female sex was not considered to be an independent risk factor, in agreement with the ESC 2012 guidelines.21
The estimates for annual risks of the outcome of “stroke” used in the 2014 CCS update
What is the current definition of NVAF?
The term “nonvalvular AF” has been used for at least 35 years29 but has never been satisfactorily defined. In the 1950s, observational reports suggested that AF was associated with a very high risk of thromboembolic events in patients with rheumatic mitral stenosis, the most common form of chronic valvular heart disease (VHD) at the time. Further reports suggested that this risk could be reduced with the use of a VKA.30, 31 In the late 1970s and early 1980s it was recognized that AF was
How should we measure renal function?
The serum concentration of creatinine, a by-product of the metabolism of creatine and phosphocreatine in skeletal muscle is, in steady state, a fairly reliable indicator of kidney function. Unfortunately, the use of serum creatinine level is limited by its indirect relationship to glomerular filtration. The production of serum creatinine is proportional to muscle mass (which is modified by factors such as sex, age, muscle mass, race, and nutrition), and the clearance of creatinine is influenced
Conclusions
There are clearly many major practical questions about the application of AF guidelines that remain unanswered. We have attempted to provide expert guidance wherever possible, but on some issues (notably the duration of AF paroxysms at which anticoagulation should be instituted), only future research will provide adequate guidance.
References (62)
- et al.
Canadian Cardiovascular Society atrial fibrillation guidelines 2010: implementing GRADE and achieving consensus
Can J Cardiol
(2011) - et al.
Focused 2012 update of the Canadian Cardiovascular Society atrial fibrillation guidelines: recommendations for stroke prevention and rate/rhythm control
Can J Cardiol
(2012) - et al.
2014 focused update of the Canadian Cardiovascular Society guidelines for the management of atrial fibrillation
Can J Cardiol
(2014) - et al.
Atrial fibrillation patients categorized as “not for anticoagulation” according to the 2014 Canadian Cardiovascular Society algorithm are not “low risk”
Can J Cardiol
(2015) - et al.
Using the CHA2DS2-VASc score for refining stroke risk stratification in ‘low-risk’ Asian patients with atrial fibrillation
J Am Coll Cardiol
(2014) - et al.
The new Canadian Cardiovascular Society algorithm for antithrombotic therapy of atrial fibrillation is appropriately based on current epidemiologic data
Can J Cardiol
(2015) - et al.
Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the Euro Heart Survey on Atrial Fibrillation
Chest
(2010) - et al.
Antithrombotic therapy for atrial fibrillation: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines
Chest
(2012) - et al.
Benefit of anticoagulation unlikely in patients with atrial fibrillation and a CHA2DS2-VASc score of 1
J Am Coll Cardiol
(2015) - et al.
Should atrial fibrillation patients with 1 additional risk factor of the CHA2DS2-VASc score (beyond sex) receive oral anticoagulation?
J Am Coll Cardiol
(2015)
Outcomes among valvular heart disease patients experiencing ischemic stroke or transient ischemic attack in Olmsted county, Minnesota
Mayo Clin Proc
Late incidence and determinants of stroke after aortic and mitral valve replacement
Ann Thorac Surg
Mitral regurgitation reduces the risk of stroke in patients with nonrheumatic atrial fibrillation
Am Heart J
The risk of thromboembolism and hemorrhage following mitral valve replacement. A comparative analysis between the porcine xenograft valve and Ionescu-Shiley bovine pericardial valve
J Thorac Cardiovasc Surg
Comparison of dabigatran versus warfarin in patients with atrial fibrillation and valvular heart disease: the RE-LY trial [abstract]
J Am Coll Cardiol
Comparative performance of the CKD Epidemiology Collaboration (CKD-EPI) and the Modification of Diet in Renal Disease (MDRD) study equations for estimating GFR levels above 60 mL/min/1.73 m2
Am J Kidney Dis
Net clinical benefit of antithrombotic therapy in patients with atrial fibrillation and chronic kidney disease: a nationwide observational cohort study
J Am Coll Cardiol
The relationship between daily atrial tachyarrhythmia burden from implantable device diagnostics and stroke risk: The TRENDS study
Circ Arrhythm Electrophysiol
Subclinical atrial fibrillation and the risk of stroke
N Engl J Med
2012 HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design: a report of the Heart Rhythm Society (HRS) task force on catheter and surgical ablation of atrial fibrillation. Developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology (ESC) and the European Cardiac Arrhythmia Society (ECAS); and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). Endorsed by the governing bodies of the American College of Cardiology Foundation, the American Heart Association, the European Cardiac Arrhythmia Society, the European Heart Rhythm Association, the Society of Thoracic Surgeons, the Asia Pacific Heart Rhythm Society, and the Heart Rhythm Society
Heart Rhythm
Atrial fibrillation in patients with cryptogenic stroke
N Engl J Med
Cryptogenic stroke and underlying atrial fibrillation
N Engl J Med
Presence and duration of atrial fibrillation detected by continuous monitoring: crucial implications for the risk of thromboembolic events
J Cardiovasc Electrophysiol
Improving stroke risk stratification using the CHADS2 and CHA2DS2-VASc risk scores in patients with paroxysmal atrial fibrillation by continuous arrhythmia burden monitoring
Stroke
Epidemiologic assessment of chronic atrial fibrillation and risk of stroke: The Framingham study
Neurology
Risk factors for stroke and efficacy of antithrombotic therapy in atrial fibrillation. Analysis of pooled data from five randomized controlled trials
Arch Intern Med
Predictors of thromboembolism in atrial fibrillation: I. Clinical features of patients at risk. The stroke prevention in atrial fibrillation investigators
Ann Intern Med
Validation of clinical classification schemes for predicting stroke: results from the national registry of atrial fibrillation
JAMA
Identifying patients at high risk for stroke despite anticoagulation: a comparison of contemporary stroke risk stratification schemes in an anticoagulated atrial fibrillation cohort
Stroke
Guidelines for the management of atrial fibrillation: the Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC)
Eur Heart J
2012 focused update of the ESC guidelines for the management of atrial fibrillation: an update of the 2010 ESC guidelines for the management of atrial fibrillation. Developed with the special contribution of the European Heart Rhythm Association
Eur Heart J
Cited by (44)
Low Utility of Short-Term Rhythm Assessment Before Long-Term Rhythm Monitoring in Patients With Cryptogenic Stroke
2023, American Journal of CardiologyManagement of Atrial Fibrillation in 2021: An Updated Comparison of the Current CCS/CHRS, ESC, and AHA/ACC/HRS Guidelines
2021, Canadian Journal of CardiologyCitation Excerpt :In 2014, the CCS and AHA/ACC/HRS refined the definition to AF occurring in the absence of “rheumatic mitral stenosis, mitral valve repair, mechanical, or bioprosthetic heart valve.” In 2015, the CCS removed mitral-valve repair or bioprosthetic heart valve from the definition, with the ESC following suit in 2016.10 In 2020, the CCS/CHRS removed reference to “rheumatic valvular disease,” instead defining nonprosthetic valvular AF solely based on the severity of mitral stenosis (“moderate to severe”), in line with the ESC and the 2019 AHA/ACC/HRS guidelines (Supplemental Tables S1 and S2).5
The 2020 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Comprehensive Guidelines for the Management of Atrial Fibrillation
2020, Canadian Journal of CardiologyCitation Excerpt :The risk was further refined by the delineation of various baseline characteristics that might affect the risk of the stroke.169-173 The first widely adopted tool for stroke risk assessment was the Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack (CHADS2) score, which assigns a single point for HF, hypertension, age 75 years or older, and diabetes, and 2 points for previous stroke/systemic embolism.26,172 Unfortunately, CHADS2 was unable to adequately differentiate very low risk individuals (ie, in whom OAC is associated with a greater risk than benefit) from those at low but still clinically important stroke risk.
The Canadian Cardiovascular Society Atrial Fibrillation Guidelines Program: A Look Back Over the Last 10 Years and a Look Forward
2020, Canadian Journal of CardiologyNon-vitamin K antagonist oral anticoagulants (NOACs) for thromboembolic prevention, are they safe in congenital heart disease? Results of a worldwide study
2020, International Journal of Cardiology
The disclosure information of the authors and reviewers is available from the CCS on their guidelines library at www.ccs.ca.