Atrial Fibrillation

What is New in the 2006 ACC/AHA/ESC Guidelines

HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation. May 2007

AF: Points of Focus

•Classification, epidemiology, and mechanisms•Consequences of AF and aims of therapy•Anticoagulation•Rate control•Rhythm control•Rate vs. rhythm control: What to do?•Catheter ablation for AF: What is the current status

2

AF: Classification•First detected episode•Recurrent AF (after 2 or more episodes)

–Paroxysmal (spontaneous termination)–Persistent (lasting beyond 7 days, or termination with drugs or

DCCV)

•Permanent AF: Sinus rhythm can not be restored

•Lone AF: Pts. younger than 60. No clinical or echo evidence for cardiac disease

•Nonvalvular AF: Cases without RMV disease, prosthetic heart valve, or valve repair.

3

AF Definition

•Paroxysmal AF: Recurrent AF (2 episodes) that terminates spontaneously within 7 days.

•Persistent AF: AF which is sustained beyond seven days, or lasting less than seven days but necessitating pharmacologic or

electrical cardioversion.

•Longstanding persistent AF: is defined as continuous AF of greater than one-year duration.

•Permanent AF: Sinus rhythm could not be restored and a decision has been made not to pursue restoration of sinus

rhythm by any means, including catheter or surgical ablation.

4

AF: Prevalence and Incidence

•Prevalence:–0.4% - 1% in the general population–8% in population over 80 years old–Lone AF: Less than 12% of all AF cases

•Incidence:–0.1% per year in people < 40 years old–2.0% per year in men > 80 years old–10% is the 3-y incidence in HF patients

5

0

10

20

30

Wolf et al. Stroke 1991;22:983-988.

50–59 60–69 70–79 80–89

AF: Prevalence and StrokesThe Framingham Study

AF: Prevalence and StrokesThe Framingham Study

%

AF prevalence Strokes attributable to AF

Age Range (years)

6

AF: Common Clinical Causes

Cardiac causes

•Hypertension•Coronary artery disease•Congestive heart failure•Pericarditis/Myocarditis•Valvular heart disease

Non-cardiac causes

•Electrolyte disturbances•Thyroid dysfunction•Ethanol intoxication•Vagal/sympathetic imbalance•Pulmonary disease•Sepsis, febrile illness

Appropriate work-up should be done and reversible causes identified and treated7

AF: MechanismsAF: Mechanisms

•Rapidly firing atrial foci (hyperexcitability)•Macroreentry with fibrillatory conduction

(mother wave)•Multicircuit reentry

Remodeling acts to make multicircuit reentry a common final pathway

Nattel et al. Ann Rev Physiol 2000;62:51-77.

Multicircuit reentry(Mines, Garrey)

Mother wave(Lewis)

Hyperexcitability(Engelmann, Winterberg)

8