1. Initial Evaluation of AF


Recommendation 1 – Complete history and physical examination (2010)

All patients with atrial fibrillation should undergo a complete history and physical examination, electrocardiogram, echocardiogram, and basic laboratory investigations.Details are highlighted in Table 1 (Strong Recommendation; Low Quality Evidence). Other ancillary tests should be considered under specific circumstances. Details included in Table 3 (Strong Recommendation; Low Quality Evidence).

Values and preferences (2010)

This recommendation places a high value on a comprehensive evaluation of patients with AF and a lower value on initial costs to the health care system.


Recommendation 2 – Well-being, symptoms, and quality of life (2010)

We recommend that the assessment of patient well-being, symptoms, and quality of life be part of the evaluation of every patient with AF (Strong Recommendation, Low Quality Evidence).

Recommendation 3 – Quality of life – CCS-AF scale (2010)

We suggest that the quality of life of the AF patient be assessed in routine care using the CCS SAF scale (Conditional Recommendation, Low Quality Evidence).

Values and preferences (2010)

Recommendations 2 and 3 recognize that improvement in quality of life is a high priority for therapeutic decision making.


Recommendation 4 - Underlying causes or precipitating factors (2010)

Underlying causes or precipitating factors for AF including hypertension should be identified and treated. Details are highlighted in Table 4 (Strong Recommendation; High Quality of Evidence).


Recommendation 5 – Management of modifiable risk factors to reduce cardiovascular events (2018)

We recommend systematic and strict guideline adherent management of traditional modifiable cardiovascular risk factors and/or conditions associated with AF, in order to reduce cardiovascular events (e.g. stroke, MI, etc.) (Strong Recommendation, High Quality Evidence).

Values and preferences (2018)

This recommendation places a high value on a systematic approach to providing guideline-directed therapy for any cardiovascular risk factors and/or conditions associated with AF.

Practical tip (2018)

The detection and optimal management of risk factors and concomitant together with appropriate rate/rhythm control and stroke prevention may contribute to a reduction in cardiovascular-related emergency department visits and hospitalizations. Addressing such risk factors might be most comprehensively and efficiently accomplished through a specialized clinic or other multidisciplinary management approach, and through a standardized, systematic protocol-based approach


Recommendation 6 – Management of modifiable risk factors to reduce AF burden (2018)

We suggest that, in addition to implementing appropriate rate or rhythm control measures, an approach targeting modifiable risk markers and conditions associated with AF should be applied, to prevent recurrence of the arrhythmia and/or decrease its symptom burden (Weak Recommendation, Low Quality Evidence).

Values and preferences (2018)

The aggressive treatment of obesity and cardiometabolic risk markers/conditions (including hypertension, heart failure, diabetes, sleep apnea) has been shown to reduce AF burden and improve quality of life. This recommendation places a high value on the recognized association between these potential risk markers and conditions that are known to aggravate AF and the possibility that treatment of these may result in prevention and/or progression of the substrate that causes AF as well as improving patient symptoms.

Table 1: Etiology and Initial Investigations: Baseline Evaluation of Atrial Fibrillation for All Patients

(Table 1 from 2010 Etiology and Initial Investigations)

  • Establish Pattern (New Onset, Paroxysmal, Persistent or Permanent)
  • Establish Severity (including impact on quality of life)
  • Identify Etiology
  • Identify reversible causes (hyperthyroidism, ventricular pacing, supraventricular tachycardia, exercise, etc)
  • Identify risk factors whose treatment could reduce recurrent AF or improve overall prognosis (i.e. hypertension, sleep apnea, left ventricular dysfunction, etc)
  • Take social history to identify potential triggers (i.e. alcohol, intensive aerobic training, etc)
  • Elicit family history, to identify potentially heritable causes of AF (particularly in lone AF)
  • Determine thromboembolic risk
  • Determine bleeding risk to guide appropriate antiplatelet or antithrombotic therapy
  • Review prior pharmacologic therapy for AF, both for efficacy and adverse effects
Physical Exam
  • Measure blood pressure and heart rate
  • Determine patient height and weight
  • Comprehensive precordial cardiac examination and assessment of jugular venous pressure, carotid and peripheral pulses to detect evidence of structural heart disease
Laboratory Investigations
  • Complete blood count, coagulation profile, renal function, thyroid and liver function
  • Fasting lipid profile, fasting glucose
12-Lead Electrocardiogram
  • Document presence of AF
  • Assess for structural heart disease (myocardial infarction, ventricular hypertrophy, atrial enlargement, congenital heart disease) or electrical heart disease (Ventricular pre-excitation, Brugada syndrome)

Document ventricular size, wall thickness and function

Evaluate left atrial size (if possible, left atrial volume)

Exclude significant valvular or congenital heart disease (particularly atrial septal defects)

Estimate ventricular filling pressures and pulmonary arterial pressure


Table 2: Evaluation of quality of life (QOL) using the CCS SAF scale*

(Table 2 from 2010 Etiology and Initial Investigations)

SAF score

Impact on quality of life

Class 0


Class 1

Minimal effect on QOL

Class 2

Minor effect on QOL

Class 3

Moderate effect on QOL

Class 4

Severe effect on QOL

*The intent of the CCS SAF scale is to capture AF-related symptoms and QOL. However, the scale evaluates not only symptoms that occur during episodes of AF but also the consequences of ongoing treatment for AF (ie, medication-related side effects).

Table 3: Additional Investigations Useful in Selected Cases

(Table 3 from 2010 Etiology and Initial Investigations)


Potential Role

Chest radiography

Exclude concomitant lung disease, heart failure, baseline in patients receiving amiodarone

Ambulatory electrocardiography (holter monitor, event monitor, loop monitor)

Document AF, exclude alternative diagnosis (atrial tachycardia, atrial flutter. AVNRT/AVRT, ventricular tachycardia), symptom-rhythm correlation, assess ventricular rate control

Treadmill exercise test

Investigation of patients with symptoms of coronary artery disease, assessment of rate control

Trans-esophageal echocardiography

Rule out left atrial appendage thrombus, facilitate cardioversion in patients not receiving oral anticoagulation, more precise characterization of structural heart disease (mitral valve disease, atrial septal defects, cor triatriatum, etc)

Electrophysiologic Study

Patients with documented regular supraventricular tachycardia (i.e. atrial tachycardia, AVNRT/AVRT, atrial flutter) that is amenable to catheter ablation

Serum calcium and magnesium

In cases of suspected deficiency (i.e. diuretic use, gastrointestinal losses) which could influence therapy (i.e. sotalol)

Sleep Study (ambulatory oximetry or polysomnography)

In patients with symptoms of obstructive sleep apnea or in select patients with advanced symptomatic heart failure

Ambulatory blood pressure monitoring

In cases of borderline hypertension

Genetic testing

In rare cases of apparent familial AF (particularly with onset at a young age) with additional features of conduction disease, Brugada syndrome or cardiomyopathy

Table 4: Etiology and Initial Investigations: Potential Causes of Atrial Fibrillation

(Table 4 from 2010 Etiology and Initial Investigations)

Cardiac Causes
  • Hypertension
  • Heart failure*
  • Coronary artery disease with prior myocardial infarction
  • Including hypertrophic dilated and restrictive cardiomyopathies
  • Valvular heart disease
  • Congenital heart disease* (early repair of atrial septal defect)
  • Pericardial disease
  • Post-surgical (particularly cardiac surgery)
  • Sick sinus syndrome
  • Atrial fibrillation as a result of ventricular pacing*
  • Supraventricular tachycardia (including Wolf-Parkinson White syndrome, atrial tachycardia, atrial flutter or other)*
  • Genetic/familial

Non-Cardiac Causes

  • Obstructive sleep apnea*
  • Obesity*
  • Excessive alcohol ingestion (acute or chronic)*
  • Hyperthyrodism*
  • Vagally-mediated (i.e. habitual aerobic training)*
  • Pulmonary disease (pneumonia, COPD, pulmonary embolism, pulmonary hypertension)

Lone (idiopathic) Atrial Fibrillation

* Denotes cause for which treatment may prevent the development or recurrence of AF.

Table 5: Risk markers and co-morbid conditions associated with AF

(Table 4 from 2018)

Conventional Risk Factors

Emerging Risk Factors

Potential Risk Factors

  • Advancing age
  • Male Sex
  • Hypertension
  • HF with reduced ejection fraction
  • Valvular heart disease
  • Thyroid disease
  • Obstructive sleep apnea
  • Chronic obstructive pulmonary disease
  • Excessive alcohol intake
  • Pre-hypertension
  • Increased pulse pressure
  • HF with preserved ejection fraction
  • Congenital heart disease
  • Subclinical hyperthyroidism
  • Obesity
  • Coronary artery disease
  • Morphometric
  • Increased height
  • Increased birth weight
  • Excessive endurance exercise
  • Familial / Genetic factors
  • Tobacco Use
  • Echocardiographic ( Left atrial

dilatation, LV hypertrophy)

  • Inflammation
  • Diabetes
  • Pericardial fat
  • Subclinical atherosclerosis
  • Electrocardiographic (Atrial

conduction delay, PR interval, Prolongation)

  • Chronic kidney disease

Cite this page content

Andrade, Jason G. et al. 2018 Focused Update of the CCS Guidelines for the Management of Atrial Fibrillation. Can J Cardiol, 2018;34: 1371 - 1392

Gillis, Anne M. et al. 2010 CCS Atrial Fibrillation Guidelines. Can J Cardiol 2010;27:27-97