Advanced lecture about Atrial fibrillation

1. In the name of Almighty
Allah the most merciful and
most compassionate

2. Presentation on Atrial
Fibrillation
Prepared by: Dr.Mirwais sohail
MD, consultant cardiologist

3. Outlines
• Introduction
• Epidemiology
• Pathogenesis
• Classification and Terminology
• Screening
• Clinical presentation
• Investigations
• Management
• Summary and recommendation
• References

4. Introduction
• Atrial fibrillation (AF) is the most commonly treated cardiac
arrhythmia. AF is generally associated with an irregularly
irregular ventricular rhythm and absence of distinct P waves.

5. Epidemiology
Prevalence: is increased with age and underlying heart diseases.
• The following data are primarily derived from studies in which an
ECG was obtained during office visit rather than ambulatory
monitoring.
• Uncommon in infant and children when present always almost
associated with structural heart diseases.
• The overall prevalence of AF is 1 percent 70% of which are 65yr
old and 45% are >75 years old.
• The prevalence of AF ranged from 0.1 percent among adults less
than 55 years of age to 9 percent in those ≥80 years of age.

6. Epidemiology
• The prevalence was higher in men than women (1.1
versus 0.8 percent

7. Incidence
• The incidence is like prevalence increasing with age and heart
diseases.

8. PATHOGENESIS
• Changes in the electrophysiology of the atrial myocardium are
likely important.
• Sustained AF seems to require the development of multiple
wavelets, rather than the single wavefront as seen in atrial
flutter. As AF becomes established, the refractory period of the
atrial muscle shortens. This electrophysiologic change
predisposes to further AF. Conversely, when sinus rhythm is
sustained, these electrophysiologic changes reverse.

9. PATHOGENESIS
AF is usually associated with some underlying heart disease.
Atrial enlargement.
Elevation in atrial pressure.
Infiltration or inflammation of the atria.
The Framingham Heart Study performed a prospective evaluation
of the echocardiographic predictors of AF in individuals without
rheumatic heart disease. Left atrial enlargement was shown to
precede and predispose to AF. Other echocardiographic risk factors
for AF were increased left ventricular wall thickness and
reduced left ventricular fractional shortening.

10. Classification and Terminology
• AF can be classified according to its duration and length of episodes;
these were described in the 2014 American Heart Association/American
College of Cardiology/Heart Rhythm Society guidelines on AF
management [1].

11. Classification
 Paroxysmal (ie, self-terminating or intermittent) AF – Paroxysmal AF is defined as
AF that terminates spontaneously or with intervention within seven days of onset.
Episodes may recur with variable frequency.
 Persistent AF – Persistent AF is defined as AF that fails to self-terminate within seven
days. Episodes often require pharmacologic or electrical cardioversion to restore sinus
rhythm. While a patient who has had persistent AF can have later episodes of
paroxysmal AF, AF is generally considered a progressive disease.
 Long-standing persistent AF – Long-standing persistent AF refers to AF that has
lasted for more than 12 months.
 Permanent AF – Permanent AF is a term used to identify persistent AF for which a joint
decision by the patient and clinician has been made to no longer pursue a rhythm
control strategy. Acceptance of persistent AF may change as symptoms, therapeutic
options, and patient and clinician preferences evolve.

12. Classification
AF can also be classified based by the way it presents or whether specific valvular conditions are
present:
 Subclinical or occult AF – This refers to AF that is largely asymptomatic and only becomes
apparent in the setting of a thromboembolic event, acute heart failure exacerbation, other medical
illness, or upon routine electrocardiogram (ECG) done for other purposes.
 Valvular AF – This refers to patients with moderate to severe mitral stenosis; these patients have
a higher risk of stroke than patients without this condition.
 Lone AF –The term lone AF has been used to describe AF in younger patients (eg, ≤60 years)
with paroxysmal, persistent, or permanent AF who have no structural heart disease or
cardiovascular risk factors.

13. SCREENING:
We do not currently screen asymptomatic patients for AF.
In a general population and among persons >65 years of age, screening has not been
shown to be better than usual care (eg, pulse palpation on physical examination) for AF
detection. Furthermore, screening showed modest to no benefit on reducing
cardiovascular outcomes and death in one of two randomized studies. Screening may
lead to more anticoagulation, but this has not been shown to be associated with robust
protection from stroke or thromboembolic events.
The United States Preventive Services Task Force
(USPSTF) also does not recommend screening for AF.

14. CLINICAL PRESENTATION
Symptoms — AF may or may not have associated symptoms, and the spectrum of symptoms is
broad and nonspecific. Typical symptoms include the following:
 Palpitations
 Tachycardia
 Fatigue
 Weakness
 Dizziness
 Lightheadedness
 Reduced exercise capacity
 Increased urination
 Mild dyspnea.

15. CLINICAL PRESENTATION
• Some patients have more severe symptoms, these include the following:
 Dyspnea at rest
 Angina
 Presyncope or rarely syncope
 Symptoms of stroke or other systemic embolic event
 Symptoms of heart failure (eg, dyspnea on exertion, peripheral edema, weight gain,
and abdominal swelling from ascites)
 Note: The severity and extent of symptoms are affected by the patient's underlying
cardiac condition, age, presence of diabetes, and rapidity and regularity of the
ventricular response.

16. History and physical examination
Descriptions of any associated symptoms should include:
●Onset or date of discovery
●Possible precipitating factors
●Frequency and duration
●Severity of episodes and symptoms
●Qualitative characteristics
●Previous medical records of any prior supraventricular arrhythmias

17. History and physical examination
• Associated conditions: The presence and status of associated
conditions such as other cardiovascular disease, cerebrovascular disease,
diabetes, hypertension, chronic obstructive pulmonary disease, o
• The presence of potentially reversible causes should be assessed (eg,
hyperthyroidism, unhealthy alcohol use). bstructive sleep apnea should be
ascertained.

18. Physical examination
• The physical examination should focus on the cardiovascular system and
any associated conditions.
• Examples include heart murmurs or arterial pulse abnormalities indicative
of mitral or aortic stenosis or regurgitation, hypertrophic cardiomyopathy,
and signs and symptoms of heart failure.
• An apical-radial pulse deficit is commonly observed in patients in AF

19. Electrocardiogram
• For all patients with suspected new-onset AF, we obtain a 12-lead ECG.
• On an ECG with AF, there are no discrete P waves but rapid, low-amplitude,
continuously varying fibrillatory waves are seen.
• The ventricular rhythm is generally irregularly irregular.

20. Electrocardiogram
A baseline ECG, preferably in sinus rhythm, should also be evaluated for
the following information:
 Markers of nonelectrical cardiac disease, such as left ventricular
hypertrophy (possible hypertension) or Q waves (possible coronary
artery disease).
 Markers of electrical heart disease, including the presence of ventricular
pre-excitation or infranodal conduction disease (bundle branch block).
 The QT interval (to identify the potential risk of antiarrhythmic therapy)
 Evidence of severe bradycardia or sinus node dysfunction

21. Echocardiogram
 We obtain a transthoracic echocardiogram (TTE) even if the physical examination is otherwise
normal.
 The TTE does not need to be performed at the time of the first visit in stable patients.
We obtain a TTE in order to evaluate:
 the size of the right and left atria
 the size and systolic function of the right and left ventricles;
to detect possible valvular heart disease,
left ventricular hypertrophy,
diastolic dysfunction.
and pericardial disease; and to assess peak right ventricular and right atrial pressures. The TTE
may also identify left atrial thrombus, although the sensitivity is low..

22. Transesophageal echocardiography
• Transesophageal echocardiography is much more sensitive for
identifying thrombi in the left atrium or left atrial
appendage and can be used to determine the need for
anticoagulation prior to pharmacologic or electrical
cardioversion.

23. Additional cardiac testing
• We refer patients with signs or symptoms of ischemic heart disease for
exercise testing.
• Exercise testing is useful to help guide pharmacotherapy for AF, as some
antiarrhythmic medications are contraindicated in patients with coronary
artery disease.

24. Laboratory testing
CBC (for anemia)
 serum electrolytes
Renal function, particularly in patients for whom a nonvitamin oral anticoagulant might be
started.
RBS
 We do not order troponin unless acute ischemia is suspected.
 Clinical or subclinical hyperthyroidism is present in less than 5 percent of patients with
AF.
TFT should be ordered for any patient with first episode of A Fib.
Other tests — A chest radiograph may be a useful diagnostic test in selected patients
with evidence of dyspnea and potential heart failure or risk of pneumonia.

25. INITIAL MANAGEMENT
A useful framework for the general care of AF patients (including those
with new-onset as well as longstanding AF) is the ABC (Atrial Fibrillation
Better Care) pathway.
"A" can be considered for anticoagulation
"B" for better symptom management
"C" for cardiovascular risk factor and comorbid disease assessment and
management.

26. Management setting
Outpatient versus emergency department:
• Most patients with newly diagnosed AF can often be managed in an outpatient setting.
• Some unstable patients require direct hospital admission or transfer to emergency
department.
• Indications for transfer to a facility with emergency services include the following:
Hemodynamic instability and/or shock (manifested as hypotension, confusion, acute
kidney injury, etc).
Suspected or confirmed myocardial ischemia/infarction.
Suspected or confirmed heart failure.
Evidence of pre-excitation (eg, Wolff-Parkinson-White syndrome) on the ECG.
Extreme, uncontrolled tachycardia.
Bothersome symptoms that may require urgent rate or rhythm control.
Hypotension for which AF is suspected to be causal or contributory

27. Indications for hospitalization
Patients in whom ablation of an accessory pathway is being considered,
particularly if the AF was highly symptomatic and associated with hemodynamic
collapse and rapid ventricular response rate.
Severe bradycardia or prolonged pauses, including after cardioversion.
Treatment of an associated medical problem, which is often the reason for the
arrhythmia (eg, HTN, infection, exacerbation of COPD, PE, pericarditis, persistent
myocardial ischemia).
Further management of heart failure or hypotension after control of the rhythm or
rate.
Initiation of antiarrhythmic drug therapy (if patient and drug characteristics
necessitate hospitalization).
Difficult-to-control ventricular rates with evidence of ischemia, congestive heart
failure symptoms or signs, and severe symptoms are indications for at least a 24-
hour admission.

28. Treatment strategy
• Rhythm control (restoration followed by maintenance of
sinus rhythm with either antiarrhythmic drugs or
radiofrequency catheter ablation)
• Rate control with atrioventricular (AV) nodal blockers.

29. Rhythm control strategy
• The main goal of rhythm control strategy is to reduce
symptoms by decreasing.
• Frequency
• Duration
• Symptoms during recurrences
• As antiarrhythmic drugs are associated with a potential
serious adverse side effects, particularly proarrhythmia,
they should be prescribed only by well experienced
practitioners.

30. Rhythm control strategy
Rhythm can be achieved either by:
• Antiarrhythmic drugs.
• Non-Pharmacologic methods

31. Indications
There are three settings in which a rhythm control
strategy for the maintenance of sinus rhythm should
be considered.
A)Persistent symptoms (palpitations, dyspnea,
lightheadedness, angina, syncope, and heart failure) despite
adequate rate control.
B) An inability to attain adequate rate control (to prevent
tachycardia-mediated cardiomyopathy).
C) Patient preference. Some patients will strongly prefer to
avoid either paroxysmal or persistent AF.

32. INITIAL MANAGEMENT DECISIONS
Prior to selecting and initiating antiarrhythmic drug
therapy, the following issues should be considered.
Rhythm versus rate control
Addressing precipitating factors
Anticoagulation
AV nodal blocker therapy
Possible role of angiotensin inhibition
Restoration of sinus rhythm

33. Rhythm versus rate control
• The choice between a rhythm- or a rate-control
strategy is determined by many factors, including
patient age, the degree to which symptoms interfere
with the quality of life, and concerns about
antiarrhythmic drug therapy or radiofrequency catheter
ablation.

34. Addressing precipitating factors
• Before initiating a rhythm control strategy, any risk factors for
AF should be addressed. Examples include hyperthyroidism,
hypertension, heart failure, and excess alcohol intake.
• Maintenance antiarrhythmic drug therapy is not recommended
after cardioversion in a patient with a transient or reversible
cause (such as cardiac surgery, pericarditis, or pulmonary
embolism).
• Beta blocker can be used as option in these people in order to
prevent from recurrences, after restoration of sinus rhythm.
• In symptomatic patient short term antiarrhythmic drug can used
until the underlying disease is treated.

35. Anticoagulation
• Chronic anticoagulation is required with either rhythm
or rate control in most patients.
• However, anticoagulation is required for at least
3weeks prior to, during, and for at least 4weeks after
cardioversion in patients with AF duration of longer than
48 hours. After 4weeks of anticoagulation, individuals
who do not require long-term anticoagulation can
discontinue the medication.

36. AV nodal blocker therapy
• An atrioventricular (AV) nodal blocker is usually started
before, or simultaneously with, antiarrhythmic drug
therapy in patients who have demonstrated a moderate
to rapid ventricular rate (≥110 beats per minute)
during AF, Slowing of the rate generally improves
symptoms prior to the restoration of sinus rhythm.
• A beta blocker, or rate-slowing calcium channel blocker
such as verapamil or diltiazem , is often used if there
are no contraindications.
• Digoxin is often used in patients with AF associated with
systolic heart failure because of its beneficial effect on
symptom control.

37. Possible role of angiotensin inhibition
• Possible role of angiotensin inhibition — The
possible role of angiotensin inhibition to prevent
recurrent AF is discussed elsewhere.

38. SELECTING AN ANTIARRHYTHMIC
DRUG
• The choice of drug is significantly influenced both by
drug and patient characteristics. As with all therapeutic
interventions, the choice of agent should take into
account the benefit to risk ratio of the therapy chosen.

39. The following points should be kept in mind while
starting antiarrhythmic therapy
• Amiodarone , dofetilide , flecainide , propafenone , sotalol ,
and less commonly dronedarone are the drugs we
recommend to maintain sinus rhythm.
• The following points regarding antiarrhythmic drugs should
be kept in mind in choosing therapy:
• Compared to other agents, amiodarone is associated with
the greatest likelihood of maintaining sinus rhythm, but also
with the highest risk of long-term complications.
• Quinidine , procainamide , and disopyramide are no longer
recommended for patients with AF, except perhaps in
patients with vagally mediated AF.

40. The following points should be kept in mind while
starting antiarrhythmic therapy
• Beta blockers are modestly effective in maintaining
sinus rhythm and can be tried first in selected patients,
such as those without structural heart disease who are
concerned about proarrhythmia.
• Of course beta blockers may have already been
initiated to slow the ventricular rate in AF.

41. The following patient characteristics may
influence decision making
• The clinical features of the patient, such as presence or
absence of clinical heart disease. We believe it is
prudent to obtain a two-dimensional echocardiogram to
screen for structural heart disease (eg, left ventricular
systolic dysfunction, left ventricular hypertrophy, or
valvular heart disease).
• The presence of paroxysmal compared to persistent AF.
As examples, our experts rarely use dofetilide for
paroxysmal AF and infrequently choose dronedarone for
persistent AF due to reduced efficacy compared
with amiodarone.

42. The following patient characteristics may
influence decision making
• The presence of vagally-mediated AF [ 16,17 ]. The 2010
European Society of Cardiology and the 2006 American College
of Cardiology/American Heart Association/European Society of
Cardiology guidelines suggest that, because of its long-lasting
anticholinergic activity, disopyramide may be considered in
patients with vagally-induced AF.
• For patients with adrenergically-mediated AF (eg, occurring
during exercise or other activity), we suggest beta blockers as
first-line therapy, followed by sotalol and amiodarone.

43. AF without structural heart disease
• Patients without structural heart disease include those with
hypertension who do not have left ventricular hypertrophy. The
author and reviewers of this topic generally select flecainide as
the first antiarrhythmic drug for these patients due to its
relatively good side effect profile, efficacy, and ease of use.

44. Referral to cardiologist
• AF is a common medical problem and can often be managed by primary care physicians
without need for consultation with a cardiologist.
• We suggest patient referral when the physician is not comfortable with decision-
making or when catheter ablation of AF is under consideration. Also, when
cardioversion or antiarrhythmic drugs are contemplated, cardiology consultation is
advantageous.

45. Anticoagulation
• Every patient with AF should be evaluated for the need for antithrombotic therapy to
prevent systemic embolization even for the first AF episode.
• This is accomplished by use of a risk-scoring system for incident stroke called the
CHA2DS2-VASc score.
• Patients who require antithrombotic therapy include those in whom cardioversion to sinus rhythm is
being considered.
• And those who meet criteria for long-term anticoagulation.
• All patients whose risk of embolization exceeds the risk of bleeding are candidates for long-term
antithrombotic therapy.

46. Cardiovascular risk factors
Identifying and treating risk factors and comorbidities may help with AF symptoms and
burden.
Common risk factors and comorbidities that can lead to the development of AF include:
• Advanced age
• Hypertension
• Diabetes
• Obstructive sleep apnea
• Heart failure
• And obesity

47. Unstable patients
• In some hemodynamically unstable patients who manifest with signs or
symptoms such as hypotension, altered mental status, or heart failure,
we attempt ventricular rate control.
• Slowing of the ventricular rate will sometimes lead to spontaneous
reversion to sinus rhythm.
• Rate control is usually performed with a beta blocker or calcium channel
blocker.
• If the patient remains hemodynamically unstable, emergency
cardioversion should be performed, particularly if the hemodynamic
compromise is due to an uncontrolled rapid ventricular rate.

48. continue……..
• If emergency cardioversion is required , the risk of thromboembolic event
needs to be considered.
• Most patients who will undergo cardioversion should be anticoagulated as
soon as the decision is made to cardiovert or after assessment of their
clinical thromboembolic risk based on their CHA2DS2-VASc score.
• Once the patient becomes hemodynamically stable, the remainder of the
acute and long-term management is similar to that of stable patients.

49. Stable patients
• For stable patients with new-onset AF who do not meet the above criteria
for emergency management and in whom we have performed an
evaluation, we try to accomplish the following in the outpatient setting:
 Evaluate the need to slow the ventricular rate.
 Discuss the possible need for cardioversion with the patient. If the
patient is highly symptomatic or if there is new-onset AF even in the
absence of symptoms, we usually attempt cardioversion.
 Determine the need for acute and long-term anticoagulant therapy.
 Discuss the cause (if known) and natural history of AF
 Schedule follow-up.

50. LONG-TERM MANAGEMENT
Early follow-up
• Follow-up after an acute episode is necessary to evaluate
• The safety and efficacy of rate or rhythm control
• Patient adherence with anticoagulant and antiarrhythmic therapy
• Need for continued therapies for AF
• To discuss any strategies to reduce AF recurrence
• And to assess the functional status of the patient
• For many patients, a one-week follow-up visit, or as soon as possible

51. Prevention of thromboembolism
• Following initial pre- and post-cardioversion anticoagulation, the decision
to continue long-term anticoagulation following a single reversible incident
is debatable, and the decision is highly individualized based on the
presumed future risk of recurrent AF in that individual (vis a vis CHA2DS2-
VASc score).

52. AF recurrence
• Continuous cardiac monitoring studies have shown that approximately 90
percent of patients with AF have recurrent episodes of AF .
• However, up to 90 percent of episodes are not recognized by the patient.

53. Methods to reduce AF recurrence
• Alcohol reduction – Alcohol is a modifiable risk factor for AF, and among
people who consume an excessive amount of alcohol, reduction and
abstinence appear to decrease the risk of recurrent AF and time in AF.
• Weight loss and physical activity – Among patients with AF, both of
these measures can lead to healthy cardiac remodeling and reduce AF
burden and cardiovascular mortality.

54. Sequelae
• In the absence of a reversible precipitant, AF is typically
recurrent.
• AF is associated with increased risk of mortality, stroke, silent
cerebral ischemia, cognitive impairment, dementia, and heart
failure. Physical activity and higher cardiorespiratory fitness
may protect against mortality in AF.

55. SUMMARY AND RECOMMENDATIONS
• Background – Atrial fibrillation (AF) is the most common cardiac arrhythmia that can have
adverse consequences related to a reduction in cardiac output (symptoms) and atrial and
atrial appendage thrombus formation (stroke and peripheral embolization).
• Classification – Patients are classified as having paroxysmal, persistent, longstanding
persistent, or permanent AR. Other classifications include subclinical or occult AF.
• Screening – We do not screen asymptomatic patients for AF. There is no sufficient evidence
that screening for AF will substantially detect more AF or protect against cardiac events.
Electrocardiograms (ECGs) do not appear more effective than pulse palpation at AF detection.
• Presentation and Evaluation – A new diagnosis of AF can present in a variety of ways;
sometimes the patient has symptoms of AF and other times it is picked up incidentally.
• Essential information from the patient's symptoms and past medical history, physical
examination, electrocardiogram (ECG), and a transthoracic echocardiogram (TTE) should be
obtained at the time of diagnosis and periodically during the course of the disease. Additional
laboratory testing, such as thyroid stimulating hormone assay, and ambulatory ECG
monitoring may be necessary.

56. SUMMARY AND RECOMMENDATIONS
Initial steps in all patients
• It is important to decide whether the patient should be managed as an outpatient or in the
emergency room or acute hospital setting. When deciding, we take the patient's presentation,
symptom burden, and associated conditions into consideration.
• Other initial steps for all patients include consideration of antithrombotic therapy, treatment of
potentially reversible triggers of AF, and cardiovascular risk factor management.
• Acute symptom management – Symptom management starts with rate control of acute AF
episodes and early decision-making regarding the need for cardioversion.
• Unstable patients – In some hemodynamically unstable patients, ventricular rate control can be
attempted; slowing of the ventricular rate sometimes leads to spontaneous reversion to sinus
rhythm. If rate control does not work and the patient remains hemodynamically unstable, we pursue
cardioversion; if we decide to perform emergency cardioversion, the risk for a thromboembolic
event needs to be considered.

57. SUMMARY AND RECOMMENDATIONS
• Stable patients – For stable patients, usually in the nonacute care setting, we discuss the
need for possible cardioversion, need for acute and long-term anticoagulant therapy, the
cause (if known), and natural history of AF.
• Long-term management – Follow-up after an episode of acute AF is necessary to
evaluate the safety and efficacy of rate or rhythm control, patient adherence with
anticoagulant and antiarrhythmic therapy, need for continued therapies for AF, to discuss
any strategies to reduce AF recurrence, and to assess the functional status of the patient.
• Sequelae – In the absence of a reversible precipitant, AF is typically recurrent. AF is
associated with increased risk of mortality, stroke, silent cerebral ischemia, cognitive
impairment, dementia, and heart failure. Physical activity and higher cardiorespiratory
fitness may protect against mortality in AF

58. References
• European Society of Cardiology guidelines
• American College of Cardiology guidelines
• American Heart Association guidelines
• European Society of Cardiology guidelines
• UpToDate
• Medscape

59. Any question?

60. Thanks from your
attention