AF ATRIAL fibrillation DM CARDIOLOGY AHA/ACC GUIDELINES NOAC IN ATRIAL fibrillation

1. Department of Cardiology
MDM Hospital
Jodhpur
2019
AHA/ACC/HRS
Focused Update
of the 2014
AHA/ACC/HRS
Guideline for the
Management of
Patients With
Atrial Fibrillation

2. INTRODUCTUION
Atrial fibrillation (AF) is the most common sustained
arrhythmia encountered in clinical practice.
It accounts for 1/3 of hospital admissions for cardiac rhythm
disturbances.
AF is a global epidemic and has adverse effects on long term
morbidity and mortality.
There is a significant difference in the incidence of AF in
various populations.
Studies reported a lower incidence of AF in Indian , Asians and
African Americans as compared with White populations.

3. INTRODUCTION
The worldwide age-adjusted prevalence of AF is estimated at
0.596% in men and 0.373% in women ,a total of 33 million.
Studies from India have shown that the mean age of patients
with AF is nearly a decade younger than the Western cohort.
The commonest underlying etiology in Indian patients with AF
in the IHRS-AF registry was also reported to be RHD in 47.8%.
Studies from India reported that RHD was present in nearly 61%
to 75% of AF patients below 50years of age.
A study by Rao et al further observed that hypertension and
ischemic heart disease was more frequent after 50 years of age.

4. INTRODUCTION
The prevalence of AF varies with the complexity of rheumatic heart disease in Indian
population study :
16% with isolated MR.
29% with MS.
52% with coexisting MR and MS.
70% with mixed mitral and tricuspid valve disease.

7. ESC guidelines 2012 defined VALVULAR AF as rheumatic valvular
disease (predominantly mitral stenosis) or prosthetic heart valves.
2014 AHA/ACC/ HRS guidelines defined non-valvular AF as AF in the absence of rheumatic
mitral stenosis or a mechanical heart valve, but added bioprosthetic heart valves or mitral
valve repair within the “valvular heart disease” group.
LONE and “IDIOPATHIC” AF generally refer to younger AF patients who have no clinical or
echo evidence of cardiopulmonary disease, hypertension, or diabetes mellitus.
LONE/IDIOPATHIC : However, this categorization is being abandoned since the category of
lone AF no longer has mechanistic or clinical utility.
Similarly, the term “chronic AF” has variable definitions and should not
be used to describe populations of patients with AF.

8. Mechanism of Atrial Fibrillation
Two concepts of the underlying mechanism of AF :
• Factors that trigger AF.
• Factors that maintain the arrhythmia.
In general, patients with frequent, self-terminating episodes of AF
are likely to have a predominance of factors that trigger AF.
Whereas patients with AF that does not terminate spontaneously
are more likely to have a predominance of perpetuating factors.

9. TRIGGERS
AF triggering factors include
Sympathetic or parasympathetic stimulation.
Bradycardia
PACs - This may be the most common cause
Atrial flutter
Supraventricular tachycardias
Acute atrial stretch
Catheter ablation of the initiating PACs or SVT can be curative in such patients.

10. PV TRIGGERS Triggering foci of rapidly firing cells within the sleeves of
atrial myocytes extending into the pulmonary veins is the underlying
mechanism in most cases of PAROXYSMAL AF
90% of AF triggering foci that are mapped during EP studies in patients
with PAROXYSMAL AF occur in the PVs
NON-PV TRIGGERS foci within the SVC, small muscle bundles in the
ligament of Marshall, and the musculature of the CS have been identified
The BASIC Concept is that the site of origin is often within a venous
structure that connects to the atrium

11. Mechanism of Maintenance of Atrial Fibrillation
Multiple wave re entry hypothesis : AF is sustained by multiple
randomly wandering wavelets in both atria that collide with each other and
extinguish themselves or create new, daughter wavelets that continually re excite
the atria and perpetuate the arrhythmia.
It has been suggested that at least four to six independent wavelets are required to maintain AF.
Localized source hypothesis : This hypothesis suggests that AF
is intermittently maintained by a small number of localized (spatially
stable) high-frequency sources with periods of self-sustaining
disorganization.Rotors and focal sources exhibit 1 : 1 activation within their
spatial domain, with peripheral disorganization.

12. VAGALLY MEDIATED AF : In some patients with structurally normal hearts, AF is precipitated
during conditions of high-parasympathetic tone, such as during sleep and following meals.
Avoidance of drugs, such as digoxin, that enhance parasympathetic tone has been suggested in
these patients.
ADRENERGIC MEDIATED AF : Adrenergic stimulation, such as that during exercise, can also
provoke AF in some patients by causing Triggered activity.
Adrenergic system causes excess intracellular Ca+2 and trigger automaticity.

13. The Pathophysiological Triangle in Atrial Fibrillation

14. Unmodifiable Risk Factors
Age : The prevalence of AF increases with advancing age.
AF occurs in less than 1% of individuals younger than 60 years
6% of those older than 65 years
In more than 10% of those older than 80 years.

15. Unmodifiable Risk Factors
Gender. The age-adjusted annual incidence of AF is
higher in men compared with women (3.8 vs. 1.6
per 1000 person-years).
Race. The age-adjusted risk of developing AF is
higher in whites as compared to blacks, Asians,
and Hispanics.

16. RISK
FACTORS
FOR AF

17. RISK
FACTORS
FOR AF

18. RISK
FACTORS
FOR AF

19. CLINICAL
SYMPTOMS
OF AF

20. CLINICAL
SYMPTOMS
OF AF

21. TREATMENT

56. THANK YOU